Pigs Flashcards

1
Q

Testing for Classical Swine Fever can be complicated by the presence of which of the following viruses in swine?

  • Vesicular Stomatitis virus
  • Influenza type A virus
  • Bovine Viral Diarrhea (BVD)
  • Porcine Reproductive and Respiratory
    Syndrome virus (PRRS)
  • Porcine Circovirus Type 2 (PCV2)
A

Answer: Bovine Viral Diarrhea

Explanation
The correct answer is Bovine Viral Diarrhea (BVD).

Although BVD virus does not usually cause disease in pigs, pigs do get exposed to the virus and seroconvert. Both BVD and CSF are Pestiviruses from the family Flaviviridae.

Antibody production in pigs to BVD can cross react with some CSF assays. This can create some problems because CS is considered a foreign animal disease in the U.S.

***PowerLecture: Foreign Animal Diseases

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2
Q

As an international consultant, you are called to examine a group of feeder pigs on a farm in West Africa. The pigs have high fever, inappetence, and hemorrhages in the skin of the ears. Several have died acutely, and you find petechial hemorrhages on internal organs. The clinical signs and lesions look like classical swine fever or erysipelas, but there is one other disease you need to rule out which also has similar signs. What is this other disease?

  • Porcine parvovirus
  • Swine influenza
  • Leptospirosis
  • African swine fever
  • Swine dysentery
A

Answer: African swine fever.

Explanation
AS acts in a similar manner to classical swine fever. It is highly virulent, carried by bush pigs and warthogs, and can also be transmitted by soft ticks.

***PowerLecture: Foreign Animal Diseases

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3
Q

Two weeks ago, the owner of a small swine farm performed castrations on several litters of unvaccinated piglets. Now he calls you with the complaint that a number of pigs are walking very stiffly and two are unable to stand. On examination, you note erect ears, tail held straight out, elevated head, and a visible nictitating membrane on the stiff pigs. There are similar signs plus muscle rigidity in the down pigs. When touched, the pigs worsen and muscle spasms occur. What disease is this most likely to be?

  • Hypomagnesemia
  • Cerebellar hypoplasia
  • Selenium deficiency
  • Clostridium tetani infection
  • Aspergillus infection
A

Answer: Clostridium tetani infection

Explanation
The best prevention for all Clostridial diseases is vaccination. These pigs should be treated with penicillin, muscle relaxants, tranquilizers, tetanus antitoxin and vaccinated with tetanus toxoid. If the owner has the time, feeding these pigs orally with glucose solutions may also help survival (this is rarely done on commercial pig farms). Those surviving will need to be revaccinated in 4 weeks. You should also advise this owner on ways to castrate more effectively to avoid this problem.

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4
Q

Which of the following is one of the most common causes for diarrhea in a nursing piglet?

  • E. coli
  • Brachyspira hyodysenteriae
  • Lawsonia intracellularis
  • Trichuris suis
  • Salmonella
A

Answer: E. coli.

Explanation
The correct answer is E. coli. Enterotoxogenic strains of E. coli cause enteric colibacillosis. It occurs commonly in nursing and weanling piglets and causes watery diarrhea, dehydration, acidosis, and death. Salmonellosis, swine dysentery (Brachyspira hyodysenteriae), proliferative enteropathies (Lawsonia intracellularis), and whipworm infections (Trichuris suis) cause diarrhea most commonly in growing, finishing, or breeding pigs.

***PowerLecture: Gastrointestinal Diseases

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5
Q

You identify a pig with skin lesions characteristic of Pityriasis rosea. What should you do next?

  • Do nothing
  • Euthanize the pig
  • Give it an injection of avermectin
  • Segregate the pig from others
  • Give it an injection of penicillin
A

Answer: Do nothing

Explanation
The correct answer is to do nothing. Pityriasis rosea is a skin condition in pigs of unknown etiology. It is not a contagious condition and therefore pigs do not need to be separated from the rest of the herd. It is non-pruritic and resolves on itself with time. Almost all pigs fully recover with no effects on health or growth performance.

***PowerLecture: Dermatology

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6
Q

A 2-month old pig is presented for evaluation of lesions on the ventrum. You find multiple raised circular lesions. You tell the farmer that you suspect the lesions will resolve without further treatment. 3 weeks later, he returns, thankful that his pig has gotten all better. What condition did the pig have?

  • Sporothrix schenckii
  • Microsporum nanum
  • Erysipelothrix rhusiopathiae
  • Pityriasis rosea
A

Answer: Pityriasis rosea

Explanation
The correct answer is pityriasis rosea, a disease of unknown cause. Pityriasis rosea occurs in pigs 3-14 weeks of age and is characterized by raised circular lesions on the ventral abdomen. Pityriasis rosea resolves on its own in a few weeks without any treatment.

***PowerLecture: Dermatology

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7
Q

A swine herd with excellent biosecurity has experienced some abortions in new replacement gilts they purchased which are bred and gestating in an on off-site facility just for P1 females (parity segregation). You have diagnosed Leptospira pomona as the serovar responsible. Which of the following is the best course of action to effectively control this disease?

  • Vaccinate all sows at both the off-site (parity segregation farm) and main farm against L. pomona
  • Cull replacement gilts (parity segregation farm) and vaccinate sows on main farm
  • Treat affected pigs with chloramphenicol for 5 days
  • Depopulate and repopulate both the gilt farm (parity segregation farm) and sow farm (main farm)
  • Treat all pigs with oxytetracycline in the feed for 3 days
A

Answer: Cull replacement gilts (parity segregation farm) and vaccinate sows on main farm

Explanation
Since the disease causes reproductive problems including abortions and is maintained in a herd by renal carriers, the best thing to do if economically feasible would be to cull the entire group of replacement gilts involved. Additionally it is important to maintain strict isolation and vaccinate the rest of the sows on the main farm. There is also the possibility of treating the affected group with long term use of antibiotics (several weeks of tylosin, tetracycline, or erythromycin). Chloramphenicol use in food animals is specifically prohibited in the US.

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8
Q

Which of the following is a method of control to prevent infection of Metastrongylus lung worms in pigs?

  • Supply a clean water supply
  • Prevent access to soil containing snails
  • Raise pigs strictly on soil pasture
  • Prevent access to soil containing earthworms
A

Answer: Prevent access to soil containing earthworms

Explanation
The correct answer is to prevent access to soil containing earthworms. Earthworms are the intermediate host often involved in transmission of Metastrongylus lungworms in pigs. Direct transmission without the intermediate host can occur as well. Clinical signs include coughing and unthriftiness. If a secondary pneumonia occurs, dyspnea and abdominal breathing or “thumps” may occur. Affected pigs that are raised on pastures are often affected with both lungworms as well as ascarids.

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9
Q

You have just been called to a small outdoor swine farm. The farmer just found what appear to be 3 different litters of aborted fetuses. The sows are roaming around the pasture and it is difficult to identify which animals have aborted (there are some pregnant and non-pregnant animals in the group). There are no noticeable respiratory signs on any of the sows either. The farmer is concerned the herd is undergoing an outbreak of porcine reproductive and respiratory syndrome (PRRS) virus. What should you do next?

  • Test 10 random sows for PRRS antibodies via ELISA
  • Collect 6 aborted fetuses to test for PRRS virus via PCR
  • Collect 6 aborted fetuses to test for PRRS antibodies via ELISA
  • Test 10 random sows for PRRS antibodies virus IFA
A

Answer: Collect 6 aborted fetuses to test for PRRS virus via PCR

Explanation
The correct answer is to collect 6 aborted fetuses to test for PRRS virus via PCR. Because the outbreak appears to be just beginning, you are more likely to find the actual virus on any sample tested rather than antibodies. It takes 10 - 14 days after exposure for antibodies to be detected. Research has shown that during a PRRS abortion outbreak, approximately 50% of aborted fetuses will test positive for virus (i.e. 50% chance of detection). Entire fetuses or just thoracic fluid are appropriate samples for submission. By including 6 aborted fetuses you will have a 98.5% chance of finding the virus if it is there. At the start of an outbreak, disease prevalence will be very low and therefore a very large sampling size would be needed to find a single positive animal.

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10
Q

A herd of pigs is presented for multiple 1-2 cm round papules, pustules, vesicles, and scabs on their ventral abdomens. Young and growing pigs are most severely affected. What is the most likely diagnosis?

  • Pseudorabies
  • Swine pox
  • Greasy pig disease
  • Erysipelas
A

Answer: Swine pox

Explanation
The correct answer is swine pox. The disease is caused by a poxvirus that causes the skin lesions described in the question. All ages can be affected, but it is more commonly seen in young and growing pigs. The disease is often transmitted by biting insects, particularly lice. The disease usually does not require treatment, unless the lesions become secondarily infected. Broad-spectrum antibiotics may be helpful in this situation. Hog lice and insect vectors should be investigated and eliminated to help control swine pox. Erysipelas causes diamond-shaped skin lesions and necrosis of the ears and tail. Greasy pig disease or exudative epidermitis is caused by Staphylococcus hyicus. It causes dark, greasy, brown skin lesions in the axilla, groin, head, and face.

Pseudorabies affects the CNS, respiratory system, and causes reproductive failure.

***PowerLecture: Dermatology

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11
Q

Which of the following E. coli is most commonly found in post-weaning diarrhea in pigs?

  • 0157:H7
  • F4 (K88)
  • F6 (987P)
  • F5 (K99)
  • F41
A

Answer: F4 (K88)

Explanation
The correct answer is F4 (K88). Susceptibility to the different pili is dependent on the presence of receptors.
These receptors change as enterocytes mature in piglets. O157:7 is not known to be pathogenic in swine and is rarely found. F4, F5, F6, and F41 can all cause diarrhea in pre-weaning piglets (<3 weeks of age) but only F4 (K88) continues to be a problem into the post-weaning phase.

***PowerPage: Swine Diarrhea

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12
Q

Which of the following external parasites is considered to be the most economically important in swine?

  • Haematopinus suis
  • Demodex phylloides
  • Stomoxys calcitrans
  • Pulex irritans
  • Sarcoptes scabei
A

Answer: Sarcoptes scabei

Explanation
Sarcoptic mange can cause pruritus in sows (mainly hyperkeratotic ear lesions) and growing pigs, resulting in reduced weight gains and feed efficiency.

***PowerLecture: Dermatology

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13
Q

Which of the following mycotoxins can cause hyperestrogenism and pseudopregnancy in pigs?

  • Ergot
  • Zearalenone
  • Ochratoxin
  • Aflatoxin
  • Fumonisin
A

Answer: Zearalenone

Explanation
Zearalenone is a potent estrogenic metabolite produced by some Fusarium species. Young gilts will be most affected. Young boars will also have reduced libido.

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14
Q

A group of 20 farm pigs are being raised because the owner has extra barley and he is feeding the pigs from weaning to finish mainly on barley and table scraps. The pigs are housed outside and now approaching 150 lbs. He calls you because this week several pigs have not been able to get up. You examine three down pigs and find that they have a normal TPR but all appear to have pelvic and femoral fractures. What is the most likely diagnosis, based on this history and findings?

  • Botulism
  • Bone fractures due to nutritional imbalance
  • Mycoplasma arthritis
  • Bone fractures due to Vitamin D deficiency
  • White muscle disease due to selenium deficiency
A

Answer: Bone fractures due to nutritional imbalance

Explanation
The high dietary phosphorus and lack of calcium can result in bone resorption and spontaneous fractures.
Vitamin D3 could also be inadequate, but this is less likely if the animals are housed where they can get some sunlight.

***PowerLecture: Musculoskeletal Diseases

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15
Q

This 2-year old pot belly pig in the picture presents for eating a box of cooking salt. It is very thirsty at presentation, but otherwise clinically normal. Its blood sodium concentration is 175 mEq/dl. What is the best treatment for this pig?

  • Send the pig home and have the owner bring the pig back if it starts to show neurologic signs
  • Give Normosol R IV slowly to decrease the blood sodium concentration
  • Give IV diazepam to suppress seizures and wait for the excess salt to be excreted by the kidneys
  • Give unlimited amounts of drinking water
  • Give a bolus of 50ml/kg of D5W (5% dextrose in sterile water) as an intravenous infusion to quickly lower the blood sodium concentration
A

Answer: Give Normosol R IV slowly to decrease the blood sodium concentration

Explanation
The correct answer is to administer Normosol R IV slowly to decrease the blood sodium concentration. Salt poisoning in pigs occurs as a consequence of water deprivation (reduced amount of free water in the animal), or too much salt intake. When the blood sodium concentration is too high, water from the brain diffuses into the vasculature. The brain responds by forming hyperosmolar (idiogenic osmoles) particles to draw water back into the brain to prevent dehydration of its cells. Giving large amounts of free water in the form of drinking water or as a bolus of D5W intravenously will quickly drop the blood sodium concentration, causing a large amount of water to diffuse into the brain cells due to the hyperosmolar particles formed. Cerebral edema then ensues and neurologic signs result. Treatment should be aimed at slowly decreasing blood sodium concentration by about 1 meq/hr to prevent cerebral edema. This is best done by using a replacement fluid that approximates normal levels of sodium so as to not create too large of an osmotic gradient. Pigs showing clinical signs of brain disease usually die despite treatment.

***PowerLecture: Neurologic Diseases

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16
Q

A herd of pigs is presented for various reasons; some pigs have been found suddenly dead with no other apparent clinical signs. Some animals are febrile, lethargic, unable to rise, and have multifocal diamond-shaped skin lesions over their bodies. Some animals have swollen, painful hocks and carpi. What is the most likely causative agent/diagnosis?

  • Swine pox
  • Erysipelothrix rhusiopathiae
  • Lawsonia intracellularis
  • E. coli
  • Mycoplasma hyosynoviae
A

Answer: Erysipelothrix rhusiopathiae

Explanation
The correct answer is Erysipelothrix rhusiopathiae. There are 3 forms of erysipelas. In the peracute form, pigs are found suddenly dead with no other clinical signs. In the acute form, the pigs become lethargic, painful in their joints, anorexic, and develop diamond-shaped skin lesions. In the chronic form, the arthritis progresses to the vertebral joints and the limb joints may fuse. All three forms of the disease can appear in a herd, particularly if there is noncompliance of vaccination of the herd and if treatment is delayed. The diamond-shaped skin lesions are pathognomonic for the disease.

***PowerLecture: Multisystemic Diseases

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17
Q

A litter of 2-week old piglets is presented for incoordination, salivation, opisthotonos, and seizures. You suspect pseudorabies and perform virus isolation to confirm your diagnosis. How will you treat these piglets?

  • Treat the piglets with penicillin for secondary bacterial infections and wait for the viral infection to clear
  • Vaccinate the piglets and then repeat vaccinations again 3 weeks later
  • There is no treatment for these piglets; herd needs to be depopulated.
  • No treatment is needed; the piglets will clear the infection on their own in about a week
A

Answer: ** There is no treatment for these piglets; herd needs to be depopulated.**

Explanation
The correct answer is there is no treatment for these piglets. Currently, all commercial US swine production is free of pseudorabies and therefore a confirmed diagnosis would require the immediate depopulation of the herd. Mortality in piglets this young with pseudorabies is near 100%. Piglets less than 3 weeks of age infected with pseudorabies often die in 1-3 days. Clinical signs include fever, anorexia, vomiting, blindness, convulsions, and neurologic signs. Pigs 3-9 weeks old have similar signs but their mortality rate is much lower. They also commonly show respiratory signs such as sneezing, nasal discharge, and coughing. Pigs older than 10 weeks infected with pseudorabies are more commonly affected with respiratory signs but may show CNS signs. Most of these pigs will recover in 7-10 days. Pregnant sows infected with the virus have reproductive failure including abortion, fetal resorption, and fetal mummification.

**PowerPage Pseudorabies
**
PowerLecture: Multisystemic Diseases

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18
Q

Which of the following statements is true about pseudorabies in pigs?

  • Older pigs with the disease show respiratory clinical signs such as sneezing, nasal discharge, and coughing
  • Neonatal piglets affected with pseudorabies do not show neurologic signs
  • Older pigs with the disease usually show neurologic signs such as prostration, paddling, and convulsions
  • Pseudorabies does not affect pregnant sows
A

Answer: Older pigs with the disease show respiratory clinical signs such as sneezing, nasal discharge, and coughing

Explanation
The correct answer is older pigs with the disease show respiratory clinical signs such as sneezing, nasal discharge, and coughing. Pseudorabies in young nursing piglets tends to cause neurologic signs such as incoordination, tremors, blindness, paddling, coma, and death. Weaned pigs may have both neurologic signs and respiratory signs such as sneezing, nasal discharge, and coughing. Older pigs tend to only have respiratory signs. Pregnant sows affected with the virus often have reproductive failure.

**PowerPage: Pseudorabies
**
PowerLecture: Multisystemic Diseases

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19
Q

A local farmer calls you because they are having reproductive problems in their 600 head sow farm. For the past month they have been having trouble with sows not becoming pregnant. The heat cycles in about 20% of the sows have been quite unusual. These sows seem to be in heat for 5-6 days. They have been breeding them once a day as long as they are in heat. Their semen costs are getting out of hand and their 30 day pregnancy check for the past 2 weeks has only been 60%. Gilts appear to be affected more severely. Some gilts even seem to be in heat all the time.

The farmer knows they had been busy emptying the manure pit and spreading manure on nearby fields most of last week which has changed their usual time for heat checking sows. This week they went back to their normal breeding schedule but are still having problems. What would you recommend they do next?

  • Collect nasal swabs from 10 affected sows for influenza virus testing
  • Collect gestation and lactation feed samples for mycotoxin testing
  • Collect blood samples for 20 sows (10 affected and 10 non-affected) for parvovirus testing
  • Collect a water sample for nitrogen testing
  • Collect a urine sample for leptospirosis testing
A

Answer: Collect gestation and lactation feed samples for mycotoxin testing

Explanation
The correct answer is to collect gestation and lactation feed samples for mycotoxin testing; specifically zearalenone testing. The indications of a prolonged heat cycle suggest high estrogens. This is a case of cystic ovarian disease. High levels of zearalenone mycotoxins in the feed are the most common cause of cystic ovaries in swine. Although, parvovirus causes reproductive problems, it usually causes a high incidence of mummies. Leptospirosis manifests as late term abortions. Influenza virus infections cause an acute respiratory outbreak with high fevers and abortions. Clinical signs associated with nitrate poisoning include high respiration rate, increased incidence of diarrhea, reduced feed intake, poor growth, and increased abortions.

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20
Q

You receive a call from a local farmer who is having trouble with a gilt farrowing. This is a small producer with just 20 sows. This is the last gilt to farrow in the group. No other gilts have had any problems. The gilt started farrowing 3 hours ago. So far she has had 8 pigs born alive and 1 stillborn. The gilt seems to be straining for the past 15-30 minutes but nothing has come out. He performed a vaginal exam and “armed” her and is not able to feel anything in the birth canal. No fetal membranes have been passed. What should you tell the farmer to do next?

  • Do nothing
  • Give prostaglandins and recheck in 10 minutes
  • Go to the farm and manually extract pigs from birth canal
  • Go to the farm and perform a C-section
  • Give oxytocin and recheck the gilt in 20 minutes
A

Answer: Give oxytocin and recheck the gilt in 20 minutes

Explanation
The correct answer is to give oxytocin and recheck the gilt in 20 minutes. The normal duration of farrowing ranges from 1.5 - 4.5 hours with an average interval between pigs of 15 - 20 min.

In this case the fact that the farmer did a vaginal exam and “armed” her tells you there are no pigs in the birth canal and thus manual extraction is not possible at this time.

Prostaglandins causes luteolysis of the corpora lutea and release of relaxin, which causes relaxation of the birth canal and cervix and is primarily used to induce parturition, not to assist in dystocia. The indications that the gilt has been straining with no fetal membranes passed suggest she is not done.

Gilts traditionally have smaller litter sizes than sows. Her current numbers of 8 born alive and 1 stillborn make it difficult to know if there are any more pigs left in her or not. On average sows today will have 11 -13 pigs born alive per farrowing. The gilt has been farrowing for only 3 hours and there are no pigs stuck in the birth canal so there are no indications that a C-section is necessary at this time. Oxytocin is very effective in creating uterine contractions. The best option at this time is to administer the oxytocin and recheck the gilt in 20 minutes.

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21
Q

You have been called to a farm to fix several rectal prolapses in a group of 60 lb pigs. The pigs are not coughing and you notice that several of the gilts in the group also have reddened and enlarged vulvas. What could be causing both problems?

  • Zearalenone
  • Salmonellosis
  • Low Ca to P ratio in the feed
  • Genetic predisposition
  • Aflatoxins
A

Answer: Zearalenone

Explanation
The correct answer is zearalenone. The estrogenic effect of this mycotoxin causes edema of the vulva and sometimes edema of the rectum, predisposing to rectal prolapses. While some have suggested a genetic predisposition for rectal prolapse, there is not yet substantial evidence to prove this; additionally, genetic factors would not explain the enlarged reddened vulvas.

Calcium and phosphorus balance has no effect on either of the clinical presentations described. Severe diarrhea caused by salmonellosis can lead to rectal prolapses, but systemic manifestations such as diarrhea or coughing would likely be present as well.

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22
Q

Which of the following mycotoxins can cause hyperestrogenism and pseudopregnancy in pigs?

  • Zearalenone
  • Ochratoxin
  • Aflatoxin
  • Fumonisin
  • Ergot
A

Answer: ** Zearalenone**

Explanation
Zearalenone is a potent estrogenic metabolite produced by some Fusarium species. Young gilts will be most affected. Young boars will also have reduced libido.

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23
Q

You receive a report from your diagnostic submission on a pig with diarrhea that reveals serotype B Salmonella. Which of the following Salmonella would you be concern of?

  • Salmonella typhimurium
  • Salmonella choleraesuis
  • Salmonella enteritidis
  • Salmonella dublin
  • Salmonella newport
A

Answer: Salmonella typhimurium

Explanation
The correct answer is Salmonella typhimurium. It is important to know serotypes as actual speciation of Salmonella usually requires submission to the national veterinary laboratory and takes several weeks to complete. Knowing serotypes allows you to start considering the possible significance of the isolate. The serotypes for the other Salmonella are as follows: Dublin and Enteritidis (D), Choleraesuis (C1), and Newport (C2). Salmonella enteritidis is specific to poultry.

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24
Q

Which of the following is true about eperythrozoonosis in pigs?

  • It is often associated with anemia, fever, icterus, and reproductive failure
  • Transmission of the disease is by direct contact and aerosol
  • Clinical signs in adult pigs are more severe than in younger pigs
  • Vaccinations in piglets are effective in preventing the disease
  • Affected animals should be culled from the herd and slaughtered
A

Answer: It is often associated with anemia, fever, icterus, and reproductive failure

Explanation
The correct answer is it is often associated with anemia, fever, icterus, and reproductive failure.
Eperythrozoonosis in pigs is caused by Mycoplasma suis (previously called Eperythrozoon suis), a disease vectored by biting insects. Clinical signs include anorexia, weakness, anemia, icterus, and reproductive failure.

Younger pigs are more severely affected than older pigs. The treatment of choice for the disease is tetracycline antibiotics. Vaccines are not available for the disease.

***PowerLecture: Miscellaneous Diseases of Pigs.

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25
Q

A litter of 3-week old piglets is presented for shifting leg lameness. They have warm swollen joints in all legs, a temperature of 107.OF (41.7 C), and are dyspneic. Necropsy of one dead animal shows fibrinopurulent pleuritis and peritonitis. What is the most likely diagnosis?

  • Erysipelothrix rhusiopathiae
  • Mycoplasma hyosynoviae
  • Osteochondrosis
  • Glaesserella parasuis
A

Answer: Glaesserella parasuis

Explanation
Glasserella parasuis (formerly named Haemophilus parasuis) causes Glasser’s disease, which is usually characterized by sudden death but can often also lead to painful joints, pneumonia, and occasionally neurologic signs. Lesions show fibrinopurulent pleuritis, pericarditis, and peritonitis. Meningitis is usually responsible for the cause of neurologic signs and seizures. This disease most commonly affects piglets from 2 weeks to 4 months of age. Morbidity rate can reach up to 50-75% and mortality rate up to 10%.

Erysipelas typically occurs in grower and finisher pigs and does not result in pneumonia. Diamond-shaped skin lesions (thus the name “diamond skin disease”) are pathognomonic for erysipelas. Mycoplasma hyosynoviae and osteochondrosis do not cause fever, pneumonia, or neurologic signs, and occur mainly in growers and finishers.

***PowerLecture: Multisystemic Diseases

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26
Q

A large swine herd has recently been experiencing coughing in the feeder pigs and a few sows. A few have fevers and inappetence but most remain normal in appearance, however the weight gains in the feeder pigs have slowed and the owner is concerned. A post-mortem reveals purple to gray areas of consolidation in the cranio-ventral lungs, with a catarrhal exudate in the airways and enlarged regional lymph nodes. You identify Mycoplasma hyopneumoniae in the lungs. What is the most cost effective approach to controlling this agent?

  • Vaccination against M. hyopneumoniae
  • Improve biosecurity, as this agent is brought in by rodents
  • Cull all pigs and start over with specific pathogen free pigs
  • Eliminate carriers by test and slaughter
  • Treat all pigs with procaine penicillin for 3 days
A

Answer: Vaccination against M. hyopneumoniae

Explanation
Vaccines are effective and widely used in the US to control this disease. Air quality, ambient temperature, and ventilation must also be addressed. Because mycoplasmas do not have cell walls, treatment with penicillin is not effective.

***PowerLecture: Respiratory Diseases

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27
Q

What is the causative agent of blue eye in swine?

  • Paramyxovirus
  • Adenovirus
  • Picornavirus
  • Rotavirus
A

Answer: ** Paramyxovirus**

Explanation
The correct answer is blue eye paramyxovirus or rubulavirus.

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28
Q

A herd of pigs is presented for a sudden onset of respiratory distress with open mouthed breathing and frothy, pink, oral and nasal discharge. The pigs are lethargic, anorexic, and have a temperature of 106.OF (41.1 C). Pigs less than 6 months of age are mainly affected, but a few adults are showing clinical signs as well. What is the most likely diagnosis?

  • Swine influenza
  • Mycoplasma pneumonia
  • Atrophic rhinitis
  • Pleuropneumonia
A

Answer: Pleuropneumonia

Explanation
The correct answer is pleuropneumonia. Pleuropneumonia in pigs is caused by Actinobacillus pleuropneumoniae, a gram negative coccobacillus. The clinical signs described in the question are typical of pleuropneumonia. The disease has a rapid onset and primarily affects young pigs. The pneumonia is characterized by fibrinonecrotic and hemorrhagic lung lesions. Concurrent infections with Mycoplasma, Pasteurella, porcine reproductive and respiratory syndrome virus, or swine influenza virus are common.
Atrophic rhinitis is characterized by sneezing, coughing, lacrimation, and occurs most commonly in pigs 3-8 weeks of age. Mycoplasma pneumonia or enzootic pneumonia is characterized by a persistent dry cough.
Swine influenza can be differentiated from pleuropneumonia because swine influenza affects pigs of all ages in the herd and does not result in discharge of blood-tinged oral and nasal froth.

***PowerLecture: Respiratory Diseases

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29
Q

Which of the following causes reproductive failure in pigs by an ascending infection of the reproductive tract?

  • Leptospira interrogans
  • Parvovirus
  • Toxoplasma
  • E. coli
  • Eperythrozoon suis
A

Answer: E. coli

Explanation
The correct answer is E. coli. Other infectious agents that ascend the reproductive tract causing metritis and reproductive failure in pigs include Streptococci, Staphylococci, Actinomyces spp., Pseudomonas spp., etc. The other answer choices listed cause reproductive failure via systemic infections. Other systemic agents causing reproductive failure include PRRS, pseudorabies, brucellosis, etc.

***PowerLecture: Reproduction

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30
Q

Farrowing crates do not allow females of which species below to engage in nesting behaviors:

  • Cattle
  • Rats
  • Poultry
  • Horses
  • Pigs
A

Answer: Pigs

Explanation
Farrowing crates are utilized in pig production.

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31
Q

You receive a report from your diagnostic submission on a pig with diarrhea that reveals serotype B Salmonella. Which of the following Salmonella would you be concern of?

  • Salmonella dublin
  • Salmonella newport
  • Salmonella choleraesuis
  • Salmonella enteritidis
  • Salmonella typhimurium
A

Answer: Salmonella typhimurium

Explanation
The correct answer is Salmonella typhimurium. It is important to know serotypes as actual speciation of Salmonella usually requires submission to the national veterinary laboratory and takes several weeks to complete. Knowing serotypes allows you to start considering the possible significance of the isolate. The serotypes for the other Salmonella are as follows: Dublin and Enteritidis (D), Choleraesuis (C1), and Newport (C2). Salmonella enteritidis is specific to poultry.

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32
Q

A pig infected with Trichuris suis will show which of the following clinical signs?

  • Dyspnea
  • Head tilt
  • Evidence of liver disease
  • Mucoid diarrhea
  • Productive cough
A

Answer: Mucoid diarrhea

Explanation
The correct answer is mucoid diarrhea. Trichuris suis is the whipworm of pigs. It typically affects older, weaned pigs. It penetrates the mucosa and submucosa of the cecum and colon, causing a large bowel diarrhea, sometimes with blood. Diagnosis can be made by finding the worms on necropsy or by finding the ova on fecal flotation. The disease can be controlled well by keeping pigs off pasture, or by avoiding exposure to contaminated pastures. Anthelmintic drugs are effective.

**PowerLecture: Gastrointestinal Diseases

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33
Q

You are called to a farm that is experiencing sudden death in a group of pigs that are scheduled to go to market in 10 days. Upon performing a necropsy, you find large amounts of blood in the small intestine and spiral colon. The blood is red and clotted. There is no gross thickening of the intestinal mucosa. Your diagnosis is which of the following?

  • Hemorrhagic bowel syndrome
  • Stomach ulcer
  • Erysipelas rhusiopathiae
  • Acute ileitis
  • Intestinal torsion
A

Answer: Acute ileitis

Explanation
The correct answer is Acute ileitis or proliferative hemorrhagic enteropathy or PHE caused by Lawsonia intracellularis. The name PHE can be deceiving as its acute nature does not always allow for gross evidence of proliferation. Lesion location in the small intestines as well as indications of red clotted blood is almost pathognomonic for the condition. Hemorrhagic bowel syndrome and intestinal torsion are not associated with intraluminal coagulated blood on necropsy. Digested blood is a sequelae to stomach ulcers. Erysipelas does not cause enteric pathology.

34
Q

Which of the following is true of Trichuris suis?

  • It is a whipworm that causes mucohemorrhagic diarrhea in pigs of all ages
  • It is a kidney worm in pigs that causes renal failure
  • It is a roundworm found in pig stomachs causing vomiting
  • It is a roundworm that is found in the lungs of pigs and causes coughing
  • It is a thread worm in pigs found in the cecum
A

Answer: It is a whipworm that causes mucohemorrhagic diarrhea in pigs of all ages

Explanation
The correct answer is it is a whipworm that causes mucohemorrhagic diarrhea in pigs of all ages. Trichuris suis occurs most commonly in pigs less than 6 months of age but can affect any age group. Clinical signs include dehydration, anorexia, mucohemorrhagic diarrhea, and sometimes death. The worms are found in the cecum and colon. Controlling the disease includes treating sows with anthelmintics a week or two before farrowing and moving them to a clean pasture. Raising swine off soil also helps control the disease.

***PowerLecture: Gastrointestinal Diseases

35
Q

Edema disease of pigs is caused by which agent?

  • Clostridioides difficile
  • Enterotoxigenic E. coli
  • Salmonella
  • Enterohemorrhagic E. coli
  • Clostridium perfringens
A

Answer: Enterotoxigenic E. coli

Explanation
The correct answer is enterotoxigenic E. coli. Edema disease is a fatal disease of rapidly growing weaned pigs.

Clinical signs include subcutaneous edema, convulsions, dysphonia, diarrhea, swollen eyelids, and acute death.

The disease is rarely ever seen prior to weaning and occurs in pigs that are on high-protein and high-energy diets. The disease results from a vasculitis that occurs due to an enterotoxin formed from enterotoxigenic E. coli. Gross lesions include subcutaneous and intestinal edema, pericardial effusion, pleural effusion, ascites, and hemorrhages on the epicardium and endocardium. Pigs affected by edema disease do not have a fever which helps differentiate it from Streptococcus suis infections which also commonly manifests as CNS signs and do cause pyrexia.

***PowerLecture: Neurologic Diseases

36
Q

Which of the following E. coli is most commonly found in post-weaning diarrhea in pigs?

  • F5 (K99)
  • F6 (987P)
  • 0157:H7
  • F41
  • F4 (K88)
A

Answer: F4 (K88)

Explanation
The correct answer is F4 (K88). Susceptibility to the different pili is dependent on the presence of receptors.
These receptors change as enterocytes mature in piglets. O157:7 is not known to be pathogenic in swine and is rarely found. F4, F5, F6, and F41 can all cause diarrhea in pre-weaning piglets (<3 weeks of age) but only F4 (K88) continues to be a problem into the post-weaning phase.

***PowerPage: Swine Diarrhea

37
Q

While visiting a porcine operation, the managers ask you about several pigs that have been sporadically dying. You examine several live pigs in the group and notice no immediate abnormalities other than occasional coughing. At that point, you tell them you are unsure of the cause of sporadic death and you would like them to give you a pig for necropsy next time one of them dies. As it happens, you are delivered a pig for necropsy a week later. At the time of necropsy the most significant findings were white spots on the liver and an intestinal obstruction of large 20-40cm worms in the small intestine which were likely the cause of death (see image). With what medication should you treat the rest of the pigs?

  • Metronidazole
  • Fenbendazole
  • Flumazenil
  • Sulfamethazine
  • Fluconazole
A

Answer: Fenbendazole

Explanation
The necropsy findings are consistent with an infection of Ascaris suum. This is the roundworm of pigs. These little worms have the ability to occasionally cause intestinal obstruction in large infestations. They can also migrate into the bile ducts and liver, causing characteristic “milk spots” on the liver.

In the A. suum life cycle, the pig ingests an egg with an L2 larva inside, which then undergoes hepatic migration (milk spots), migrates to the lungs and becomes an L3 larva, enters the alveoli and finally gets coughed up. The larval migration can sometimes cause rapid shallow breathing that many refer to as “thumps”.

Diagnosis is by fecal flotation and clinical signs for the most part. Treatment options are wide and include ivermectin, fenbendazole, pyrantel, levamisole and other ascaracides.

Fenbendazole is a benzimidazole anthelmintic with a broad spectrum against many gastrointestinal parasites such as roundworms, hookworms, whipworms, pinworms, and strongyles.

Metronidazole is an antibiotic with a mainly anaerobic spectrum. It is also useful in the treatment of certain parasites such as giardia. Fluconazole is an antifungal and commonly used to treat coccidiodomycosis in small animals. Flumazenil is a reversal for benzodiazepines. Sulfamethazine is an antibiotic that has been used in the treatment of coccidiosis in pigs.

38
Q

The pot bellied pig in the picture is infected with Trichinella spiralis. How is this parasite in pigs transmitted?

  • Ingestion of snails, the intermediate host
  • Ingestion of encysted larvae in feces
  • Ingestion of earthworms, the intermediate host
  • Ingestion of encysted larvae in urine
  • Ingestion of encysted larvae in muscle
A

Answer: Ingestion of encysted larvae in muscle

Explanation
The correct answer is ingestion of encysted larvae in muscle. Trichinella spiralis is a worm that can infect most mammals. It commonly affects wildlife, including bears, horses, rats, marine mammals, and of course, pigs.

Infection in pigs is often due to ingestion of rodents, raw garbage, or cannibalism of meat infected with the cysts. Humans can get the infection by eating inadequately cooked pork. Control in pigs is to prevent them from cannibalizing the dead, prevent them from eating rodents, and by cooking the garbage that is fed to them.

39
Q

You necropsy a pig that had a history of persistent hemorrhagic diarrhea and find a severely thickened and inflamed ileum. What is the likely diagnosis?

  • Rotavirus infection
  • Lawsonia intracellularis infection
  • Isospora suis infection
  • Salmonella infection
  • Clostridium perfringens infection
A

Answer: Lawsonia intracellularis infection

Explanation
The correct answer is Lawsonia intracellularis infection. Lawsonia intracellularis is an intracellular gram negative bacillus anaerobe that causes soft buttery stool in some and acute hemorrhagic diarrhea in others. This disease most commonly occurs in weaned and older pigs. Weight loss is the most consistent sign, and the lesions are as described in the question. This disease is considered to be similar to Johne’s disease in cows. The other answer choices all more commonly cause diarrhea in unweaned and/or young piglets (early nursery). Gross lesions on necropsy included proliferative ileitis and edematous mesentery with mesenteric lymphadenopathy.

**PowerPage: Swine Diarrhea
**
PowerLecture: Gastrointestinal Diseases

40
Q

A group of 4-month old outdoor pigs are presented for icterus, failure to thrive, unthriftiness, and dyspnea. Necropsy of one of the pigs shows white spots in the liver, pulmonary edema, and many roundworms in the small intestine, stomach, and bile ducts. What is the most likely diagnosis?

  • Fasciola hepatica
  • Trichuris suis
  • Stephanurus dentatus
  • Ascaris suum
  • Metastrongylus spp.
A

Answer: Ascaris suum

Explanation
The correct answer is Ascaris suum. Ascaris suum are found in the small intestine of pigs. If there is a large burden of the worms, they can cause obstruction of the intestine, migrate into the bile ducts and cause icterus.

Migration through the liver causes fibrosis or “white spots” Pulmonary edema can also be a sequela of the larvae, causing abdominal breathing or “thumps.”

Ascaris suum infections are common in outdoor swine due to high environmental contamination.

Trichuris suis is a whipworm found in the cecum and large intestine. Metastrongylus is a lung worm. Stephanurus dentatus is the kidney worm of pigs. Fasciola hepatica is a liver fluke.

41
Q

You have just been called to a small outdoor swine farm. The farmer just found what appear to be 3 different litters of aborted fetuses. The sows are roaming around the pasture and it is difficult to identify which animals have aborted (there are some pregnant and non-pregnant animals in the group). There are no noticeable respiratory signs on any of the sows either. The farmer is concerned the herd is undergoing an outbreak of porcine reproductive and respiratory syndrome (PRRS) virus. What should you do next?

  • Collect 6 aborted fetuses to test for PRRS antibodies via ELISA
  • Collect 6 aborted fetuses to test for PRRS virus via PCR
  • Test 10 random sows for PRRS antibodies via ELISA
  • Test 10 random sows for PRRS antibodies virus IFA
A

Answer: Collect 6 aborted fetuses to test for PRRS virus via PCR

Explanation
The correct answer is to collect 6 aborted fetuses to test for PRRS virus via PCR. Because the outbreak appears to be just beginning, you are more likely to find the actual virus on any sample tested rather than antibodies. It takes 10 - 14 days after exposure for antibodies to be detected. Research has shown that during a PRRS abortion outbreak, approximately 50% of aborted fetuses will test positive for virus (i.e. 50% chance of detection). Entire fetuses or just thoracic fluid are appropriate samples for submission. By including 6 aborted fetuses you will have a 98.5% chance of finding the virus if it is there. At the start of an outbreak, disease prevalence will be very low and therefore a very large sampling size would be needed to find a single positive animal.

42
Q

You are investigating a case of high mortality in 14 week old pigs. You are suspicious of Porcine circovirus associated disease (PCVAD). What sample do you need to submit to a laboratory to contirm your diagnosis?

  • Lymphoid tissue for histology
  • Serum sample for PCR testing
  • Whole blood for complete blood count (CBC)
  • Serum sample for ELISA antibody testing
  • Serum sample for virus isolation
A

Answer: Lymphoid tissue for histology

Explanation
The correct answer is lymphoid tissue for histology. A diagnosis of PCVAD requires 3 parts:
1) at least a doubling of mortality (clinical history)
2) demonstration of lymphoid depletion (histopathology)
3) high number of PCV2 antigen in the lesion (immunohistochemistry on tissue)

***PowerLecture
• Multisystemic Diseases (11:04)

43
Q

A client with a pet pot belly pig carries it into your clinic one day, cradling it lovingly against her body. The complaint is pruritus and skin lesions; she mentions that she and her boyfriend also have similar lesions. You do a skin scraping on the pig and find Sarcoptes scabiei. What treatment should you now recommend?

  • Dip the pig daily in toxaphene
  • Use corticosteroids to stop the itching, as all the skin damage is due to scratching
  • No treatment is necessary, as Sarcoptes spontaneously die after 3 weeks and the animal heals
  • Treat pig for lice
  • Treat the pig for mange
A

Answer: Treat the pig for mange

Explanation
The best treatment drugs are the avermectins; two doses at 2-week intervals will be required. The mange mite completes its entire life cycle on the pig. Also advise her to see her physician for herself and boyfriend. Finally, tell her this can spread to other species of animals, and the pig must be quarantined away from all other pets and livestock.

***PowerLecture: Dermatology

44
Q

What is the causative agent of transmissible gastroenteritis (TGE) in swine?

  • Isospora suis
  • Parvovirus
  • Brachyspira hyodysenteriae
  • Coronavirus
  • Lawsonia intracellularis
A

Answer: ** Coronavirus**

Explanation
The correct answer is coronavirus. TGE is a viral disease of the small intestines causing vomiting and watery diarrhea. Mortality is 100% in piglets < 10 days old, but they seldom die if they are > 1 month old when infected.

There is no specific treatment.

***PowerPage: Swine Diarrhea

***PowerLecture: Gastrointestinal Diseases

45
Q

Which of the following agents is most likely the cause of mild diarrhea in a 3 day old pig?

  • Rotavirus
  • Whipworms
  • Transmissible gastroenteritis virus (TGE)
  • Porcine parvovirus
  • Coccidiosis
A

Answer: Rotavirus

Explanation
The correct answer is rotavirus infections. TGE infections in pigs less than 2 weeks old usually result in death.

Porcine parvovirus is associated with reproductive problems and not diarrhea in pigs. Pigs have to be at least 5 days old to be affected by coccidiosis. Whipworm infections are extremely rare in baby pigs.

**PowerLecture: Gastrointestinal Diseases

46
Q

You are examining a 200 lb replacement gilt (she is to become part of the breeding herd) with a crooked nose. There are no external signs of trauma. Her respiratory rate is normal and has a rectal temperature if 102.2 F (39 C). You suspect atrophic rhinitis. What should you do next?

  • Inject with flunixin meglumine
  • Inject with long acting tetracycline
  • Examine nasal turbinates for atrophy
  • Recommend culling her from the herd
  • Vaccinate for Mycoplasma hyorhinis
A

Answer: Recommend culling her from the herd

Explanation
The correct answer is to recommend culling her from the herd. Atrophic rhinitis (AR) is caused by Bordetella bronchiseptica and Pasteurella multocida type D. Pigs become infected from the sow shortly after birth. The detail that this gilt is destined to be used for breeding is very important to selecting the best answer. The best way to control/eliminate AR is to select breeding stock that is negative for AR. Antibiotic treatment and flunixin meglumine will not reverse the condition and will probably not have any effects at this stage of the disease.

Mycoplasma hyorhinis does not cause nasal deviation. Examination of nasal turbinates is not practical and does not provide useful information.

***PowerLecture: Respiratory Diseases

47
Q

Which of the following is the most important problem associated with leptospirosis in pigs?

  • Abiotrophy of the spleen
  • Reproductive failure
  • Purple extremities due to vasculitis
  • Chronic kidney disease
A

Answer: Reproductive failure

Explanation
The correct answer is reproductive failure. Acute leptospirosis in young pigs causes fever, anorexia, hemolytic anemia, hemoglobinuria, jaundice, and failure to grow. Chronic infections in dams cause reproductive failure as late term abortions, mummies, or weak piglets that die in a few days. Dams usually recover, conceive again, and carry their litters to full term.

***PowerLecture: Reproduction

48
Q

A pig farmer believes that his specific pathogen-free (SPF) herd is free of both Bordetella bronchiseptica and toxigenic Pasteurella multocida, but several young pigs have recently begun to sneeze and snuffle and have a serous to mucopurulent nasal discharge. The affected pigs appear to be falling behind in growth rate. What disease is this farmer concerned about?

  • Porcine stress syndrome
  • Exudative epidermitis
  • Atrophic rhinitis
  • Pleuropneumonia
  • Swine dysentery
A

Answer: Atrophic rhinitis

Explanation
Non-progressive atrophic rhinitis is caused by B. bronchiseptica, and progressive atrophic rhinitis is caused by toxigenic P. multocida type D. They may result in loss of turbinates, facial distortion and poor weight gains.

***PowerLecture: Respiratory Diseases

49
Q

Which dermatophyte is most commonly associated with ringworm in the domestic pig?

  • Microsporum canis
  • Microsporum nanum
  • Trichophyton mentagrophytes
  • Trichophyton equinum
A

Answer: Microsporum nanum

Explanation
The correct answer is Microsporum nanum which primarily affects pigs. T verrucosum can also be found in pigs.

M. canis and M. gypseum most commonly affect dogs and cats. T. mentagrophytes and T verrucosum affect cattle and most commonly goats.

50
Q

Pigs that are housed outside, with appropriate shelter as well as enough room to roam, root, and perform natural behaviors, are still at risk for animal welfare concerns under the following conditions:

  • When piglets are weaned
  • Gestation crates are not used
  • There is a lack of human interaction
  • Farrowing crates are not used
  • Lack of protection from cold weather
A

Answer: Lack of protection from cold weather

Explanation
Pigs are extremely sensitive to cold temperatures and can experience negative welfare in cold weather.

51
Q

A local farmer calls you because they are having reproductive problems in their 600 head sow farm. For the past month they have been having trouble with sows not becoming pregnant. The heat cycles in about 20% of the sows have been quite unusual. These sows seem to be in heat for 5-6 days. They have been breeding them once a day as long as they are in heat. Their semen costs are getting out of hand and their 30 day pregnancy check for the past 2 weeks has only been 60%. Gilts appear to be affected more severely. Some gilts even seem to be in heat all the time. The farmer knows they had been busy emptying the manure pit and spreading manure on nearby fields most of last week which has changed their usual time for heat checking sows. This week they went back to their normal breeding schedule but are still having problems. What would you recommend they do next?

  • Collect nasal swabs from 10 affected sows for influenza virus testing
  • Collect a water sample for nitrogen testing
  • Collect gestation and lactation feed samples for mycotoxin testing
  • Collect a urine sample for leptospirosis testing
  • Collect blood samples for 20 sows (10 affected and 10 non-affected) for parvovirus testing
A

Answer: Collect a urine sample for leptospirosis testing

Explanation
The correct answer is to collect gestation and lactation feed samples for mycotoxin testing; specifically zearalenone testing. The indications of a prolonged heat cycle suggest high estrogens. This is a case of cystic ovarian disease. High levels of zearalenone mycotoxins in the feed are the most common cause of cystic ovaries in swine. Although, parvovirus causes reproductive problems, it usually causes a high incidence of mummies. Leptospirosis manifests as late term abortions. Influenza virus infections cause an acute respiratory outbreak with high fevers and abortions. Clinical signs associated with nitrate poisoning include high respiration rate, increased incidence of diarrhea, reduced feed intake, poor growth, and increased abortions.

52
Q

Several litters of 2 to 3 day old pigs have recently died rapidly with hemorrhagic enteritis. Post mortem lesions include mucosal hemorrhage, necrosis and emphysema in the small intestines. What pathogen is most likely to cause these signs?

  • Clostridium perfringens type C
  • Erysipelothrix rhusiopathiae
  • Salmonella choleraesuis
  • Enterotoxigenic E. coli
  • Glaesserella parasuis
A

Answer: Clostridium perfringens type C

Explanation
The age of these affected pigs along with the rapid course of hemorrhagic and necrotic enteritis help you come to this conclusion. As with many Clostridial diseases, vaccination is the most effective means of control. Other important clostridial diseases of swine include C. perfringens type A, C. difficile, C. tetani, C. botulinum, C. novyi, C. septicum, and C. chauvoei.

53
Q

You receive a report from your diagnostic submission on a pig with diarrhea that reveals serotype B Salmonella. Which of the following Salmonella would you be concern of?

  • Salmonella dublin
  • Salmonella typhimurium
  • Salmonella choleraesuis
  • Salmonella enteritidis
  • Salmonella newport
A

Answer: Salmonella typhimurium

Explanation
The correct answer is Salmonella typhimurium. It is important to know serotypes as actual speciation of Salmonella usually requires submission to the national veterinary laboratory and takes several weeks to complete. Knowing serotypes allows you to start considering the possible significance of the isolate. The serotypes for the other Salmonella are as follows: Dublin and Enteritidis (D), Choleraesuis (C1), and Newport (C2). Salmonella enteritidis is specific to poultry.

54
Q

You are called to a pig farm where a group of 130 lb pigs are experiencing sudden death. Upon arrival you notice several pigs with purple skin lesions all over their bodies. The lesions are flat and not pruritic. What is your clinical diagnosis?

  • Vesicular stomatitis
  • Erysipelas rhusiopathiae
  • Mange
  • Swine pox
  • Foot and mouth disease
A

Answer: Erysipelas rhusiopathiae

Explanation
The correct answer is Erysipelas rhusiopathiae or diamond skin disease. Swine pox, FMD and vesicular stomatitis all cause vesicular lesions (lesions not flat). Mange is a pruritic condition caused by mites.

55
Q

You are visiting a swine farm in Oklahoma with no other known swine farms located within a 5 mile radius. The pigs weigh about 220 pounds (100kg). They are from a sow farm that has been testing negative for porcine reproductive and respiratory syndrome virus (PRRS) for the past 2 years. The pigs were doing quite well until 3 days ago when they started coughing. Today, over 90% of the pigs seem to be coughing. You take rectal temperatures of 5 clinically affected pigs and they all have temperatures greater than 105 degrees F (40.6 C). There is some sneezing and you note nasal discharge in over 60% of the pigs. This nasal discharge varies from clear to thick and white. What should you recommend?

  • Vaccinate for swine influenza using an autogenous killed vaccine
  • Vaccinate for PRRS using a commercial MLV vaccine
  • Vaccinate for swine influenza using a commercial killed vaccine
  • Treat all pigs with oral antibiotics for 5 days
  • Nothing since it is most likely a viral infection and there are no antivirals approved for pigs
  • Vaccinate for PRRS using an autogenous killed vaccine
A

Answer: Treat all pigs with oral antibiotics for 5 days

Explanation
The correct recommendation is to treat all pigs with oral antibiotics for 5 days. The rapid spread of the disease (90+% in just 3 days) and the high fevers are the classic clinical presentation of a swine influenza outbreak. Although antibiotics do not treat the viral infection, secondary bacterial infections almost always occur in conjunction with swine viral respiratory infections (porcine respiratory disease complex; PRDC). Prompt treatment for secondary bacterial infections is critical, and with 90+% animal affected, all animals need to be treated. The white nasal discharges support a bacterial component.

It is unlikely that PRRS is involved, since the pigs are from a negative sow farm and are well isolated from other pigs. Vaccination is not a good option at this time because all pigs are already affected (already naturally vaccinated). It is also important to note these pigs are large (220 lbs) and some pigs will be going to market in just 2 to 3 weeks, thus there is concern with vaccine slaughter withdrawal (usually at least 21 days for vaccines) as well as minimal time for any vaccine benefit.

56
Q

You arrive at a farm where the farmer has lost 2 pigs in the past 2 days. He has 450 pigs which are currently weighing 200 lbs. The pigs seemed to be doing quite well and all appear to be eating. They all look healthy (no respiratory or enteric signs noted) and there has not been a diet change for at least 2 weeks. On arrival to the farm you find the latest mortality. The pig just died over night and is in excellent body condition. It seems to be one of the biggest pigs from the group. The abdomen is quite distended. As you perform the necropsy you find the following gross lesions (photo). No intestinal torsion/volvulus is noted. What should you do next?

  • Immediately vaccinate remaining pigs for salmonella
  • Immediately treat all remaining pigs with ceftiofur
  • Treat all pigs with tylosin in the water
  • Check intestinal content for clotted blood
  • Collect two feed samples (one from affected group and one from non-affected group)
A

Answer: Check intestinal content for clotted blood

Explanation
Your next step should be to check intestinal content for clotted blood. Your top two differentials at this time are acute ileitis or hemorrhagic bowel syndrome. Both present as sudden death and on necropsy both appear grossly as distended intestines with diffuse hemorrhagic tissue. In the case of acute ileitis, the intestinal content will be hemorrhagic and clotted.

For hemorrhagic bowel syndrome (HBS) or intestinal volvulus, the intestinal content will be hemorrhagic and liquid; non-clotted. Making the correct diagnosis is critical as in the case of acute ileitis, immediate treatment of all pigs with tylosin would be warranted. For HBS, the etiology is unknown, and there are no effective treatments.

57
Q

Several weaner pigs have developed anorexia, followed by diarrhea and edema of the eyelids, forehead and lips. The pigs also have dyspnea and are open mouth breathing. Some are weak and circling. What pathogen is the most likely cause?

  • Enterotoxogenic E. coli
  • Salmonella typhimurium
  • Transmissible gastroenteritis virus
  • Porcine Parvovirus
  • Clostridium tetani
A

Answer: Enterotoxogenic E. coli

Explanation
The edema disease producing E. coli produce a heat stable toxin called Stx2e (Shiga toxin 2e). When absorbed into the blood, this toxin destroys endothelial cells in small vessels, resulting in blood clots, hemorrhage, ischemic necrosis, and edema in vital organs, including the brain.

58
Q

What is the treatment for pityriasis rosea in pigs?

  • Ketoconazole
  • Ivermectin
  • Lincomycin
  • Euthanasia
  • No treatment is required
A

Answer: No treatment is required

Explanation
The correct answer is no treatment is required. Pityriasis rosea occurs in pigs 3-14 weeks of age and is characterized by raised circular lesions on the ventral abdomen. Pityriasis rosea resolves on its own in a few weeks without any treatment. The etiology of the disease is unknown, but may have a hereditary basis.

***PowerLecture: Dermatology

59
Q

Ascaris suum affects this part of the carcass in a pig.

  • Heart
  • Spleen
  • Liver
  • Skin
  • Kidney
A

Answer: Liver

Explanation
The correct answer is liver. The roundworm may migrate through the liver and cause characteristic “milk spots” as a result of inducing fibrosis and hemorrhage.

***PowerLecture: Respiratory Diseases

60
Q

You have arrived at a farm with a history of acute outbreak of sudden death. Pigs average 80 lbs and the producer has lost 25 pigs out of 1,150 in the last 2 days. Several of the dead pigs have blood tinged fluid coming out of their noses. Which of the following is your top differential?

  • Actinobacilus pleuropneumoniae
  • Mycoplasma hyopneumoniae
  • Porcine reproductive and respiratory syndrome (PPRS)
  • Vitamin D deficiency
  • Rodenticide poisoning
A

Answer: Actinobacilus pleuropneumoniae

Explanation
The correct answer is Actinobacillus pleuropneumoniae (APP). The virulence of APP is due to exotoxin production by the bacteria which causes a vasculitis and hemolysis, especially in the lungs.

Rodenticide poisoning of an entire group of pigs is extremely rare as it would require large amounts of poison mixed in the feed. Mycoplasma hyopneumoniae is a slow growing organism and is not associated with an acute outbreak with sudden death. Porcine reproductive and respiratory syndrome is a common cause of respiratory outbreaks in pigs but usually does not cause high mortality by itself (co-infections are the culprit). Vitamin D deficiency alters calcium and phosphorus homeostasis.

***PowerLecture: Respiratory Diseases

61
Q

Which of the following is the most effective treatment for a leptospira infection in a growing pig?

  • Fluoroquinolones
  • Vaccination with multivalent bacterins
  • Tetracyclines
  • Euthanizing the pig or depopulating the herd
A

Answer: Tetracycline

Explanation
The correct answer is long term use of
tetracyclines. Vaccinations are usually only used in the breeding herd where bacterins, containing the appropriate serovar, can reduce the prevalence of infection and leptospirosis-induced abortions.

Depopulation or euthanasia is not necessary as in growing pigs the clinical signs are not life threatening (leptospirosis-induced abortions is not a concern). Fluoroquinolone antibiotics are not useful against leptospirosis. Besides tetracycline antibiotics, other effective antibiotics include tylosin, erythromycin, and penicillins.

62
Q

A group of 4-week old piglets presents for depression, anorexia, and lethargy. They all have brown exudative spots on the skin of their heads, axillae, and groins. Some of the lesions are brown to black crusts. What is the most likely diagnosis?

  • Pityriasis rosea
  • Dermatosis vegetans
  • Pediculosis
  • Staphylococcus hyicus
A

Answer: Staphylococcus hyicus

Explanation
The correct answer is Staphylococcus hyicus. S. hyicus infections in pigs are also known as exudative epidermitis or greasy pig disease. The disease affects piglets less than 8 weeks of age and seldomly adults. The clinical signs and lesions are those described in the question. Morbidity and mortality is usually high in younger pigs. There are not many other swine diseases that appear clinically like this, so diagnosis is usually based on history and clinical signs.

Pediculosis causes pruritus and anemia.

Dermatosis vegetans is a semilethal hereditary defect that causes macules and papillomas around the coronary band of pigs. Pityriasis rosea is characterized by raised circular lesions on the ventral abdomen. Pityriasis rosea resolves on its own in a few weeks without any treatment.

63
Q

You are asked to examine a group of pigs that have just arrived from a sow farm. The pigs are 24 days old and approximately 2% of the pigs have crusty lesions over their body especially in the face area. Some pigs have lesions covering their entire body. What should be your recommendation for plan of action?

  • Treat all pigs with a topical insecticide effective against lice
  • Nothing, pigs will grow out of the condition
  • Euthanize all affected pigs
  • Separate affected pigs and treat with injectable antibiotics
  • Immediately call federal authorities
A

Answer: Separate affected pigs and treat with injectable antibiotics

Explanation
The crusty lesions all over the body, especially on the face in pigs of this age are highly suggestive of “greasy pig” disease caused by Staphylococcus hyicus. The bacterial pyoderma is contagious so it is helpful to segregate affected pigs. As pigs grow, their immune system does a better job in controlling the infection, but with a history of having some pigs with lesions all over the body, antibiotic treatment is necessary to prevent the condition from worsening in these young pigs which can lead to dehydration and/or systemic spread. There is no need to call federal authorities, since no vesicular lesions are noted.

***PowerPage: Exudative epidermitis (Greasy pig disease)

***PowerLecture: Dermatology

64
Q

Which of the following agents is most likely the cause of mild diarrhea in a 3 day old pig?

  • Rotavirus
  • Porcine parvovirus
  • Transmissible gastroenteritis virus (TGE)
  • Coccidiosis
  • Whipworms
A

Answer: Rotavirus

Explanation
The correct answer is rotavirus infections. TGE infections in pigs less than 2 weeks old usually result in death. Porcine parvovirus is associated with reproductive problems and not diarrhea in pigs. Pigs have to be at least 5 days old to be affected by coccidiosis. Whipworm infections are extremely rare in baby pigs.

65
Q

Which of the following is a reliable indicator of estrus in a pig?

  • The sow stands while being mounted by another sow
  • The sow stands while being mounted by a boar
  • Increased rooting activity
  • The sow attempts to mount other herdmates
  • Increased vocalization
A

Answer: The sow stands while being mounted by a boar

Explanation
The correct answer is the sow stands while being mounted by a boar. The sow may allow mounting by other sows or try mounting other herdmates during both proestrus and estrus, but she will only allow mounting by a boar while in estrus. Increased vocalization and rooting occur during estrus as well, but they are not as reliable as indicators.

66
Q

You are observing a commercial swine facility and notice that the producer has provided his pigs with their preferred nesting material. Which material has he provided?

  • Sand
  • Loose soil
  • Rocks
  • Fresh-cut grass
  • Straw
A

Answer: Straw

Explanation
Straw is the preferred bedding material for swine.

67
Q

Which of the following organisms has been associated with spirochaetal colitis in swine?

  • Trichuris suis
  • Salmonella Typhimurium
  • Lawsonia intracellularis
  • Brachyspira pilosicoli
  • Brachyspira hyodysenteriae
A

Answer: Brachyspira pilosicoli

Explanation
The correct answer is Brachyspira pilosicoli. B. hyodysenteriae is the causative organism for swine dysentery.

Lawsonia intracellularis causes ileitis. Trichuris suis is the porcine whipworm. Salmonella Typhimurium is associated with button ulcers in the colon.

***PowerLecture: Gastrointestinal Diseases

68
Q

Several pigs have died at a farm. Clinical signs included star gazing, blindness, seizures, ataxia, nystagmus, and head pressing. Histologic examination of the brain demonstrates perivascular infiltration of eosinophils. What is the most likely diagnosis?

  • Rabies
  • Vitamin A deficiency
  • Salt poisoning
  • Salmonella
A

Answer: Salt poisoning

Explanation
The correct answer is salt poisoning. In pigs, observation of perivascular infiltration of eosinophils in the brain is a reliable indicator of salt poisoning. Additionally, the clinical signs are consistent with this diagnosis. Salmonella would not have produced the same histologic lesions, and you would expect diarrhea. Rabies is always on the differential list, but the histologic findings are not consistent with rabies. Do you recall the diagnostic lesion for rabies? Yes, it’s negri bodies. Vitamin A deficiency does not cause perivascular eosinophilic infiltration either.

***PowerLecture: Neurologic Diseases

69
Q

An animal welfare expert is discussing a pig’s affective state. What is she referring to?

  • Stereotypies
  • Emotions
  • Physical health
  • Aggression
  • Maladaptive behaviors
A

Answer: Emotions

Explanation
The affective state is another term for emotion.

70
Q

You are called to a farm that just purchased 500 head of feeder pigs averaging 55 lb. The pigs arrived 3 days ago and everything seemed fine until today. Today there are 6 pigs that are lying down on their sides and paddling and a few others that are weak and staggering. What should you do next?

  • Check antibiotics used in the ration
  • Check the feed for mycotoxins
  • Check for signs of rodent infestation
  • Check feed availability
  • Check water availability in all pens
A

Answer: Check water availability in all pens

Explanation
The correct answer is to check water availability in all pens. The clinical presentation is very typical for water deprivation/salt toxicity. Water deprivation will result in acute cerebral edema due to the accumulation of sodium ions in the brain. To prevent further water damage, water must be turned back on slowly (small amounts frequently) to prevent further cerebral edema from occurring as the animals become re-hydrated.

***PowerLecture: Neurologic Diseases (4:37)

71
Q

You are asked to examine a group of pigs that have just arrived from a sow farm. The pigs are 24 days old and approximately 2% of the pigs have crusty lesions over their body especially in the face area. Some pigs have lesions covering their entire body. What should be your recommendation for plan of action?

  • Treat all pigs with a topical insecticide effective against lice
  • Nothing, pigs will grow out of the condition
  • Immediately call federal authorities
  • Separate affected pigs and treat with injectable antibiotics
  • Euthanize all affected pigs
A

Answer: Separate affected pigs and treat with injectable antibiotics

Explanation
The crusty lesions all over the body, especially on the face in pigs of this age are highly suggestive of “greasy pig” disease caused by Staphylococcus hyicus. The bacterial pyoderma is contagious so it is helpful to segregate affected pigs. As pigs grow, their immune system does a better job in controlling the infection, but with a history of having some pigs with lesions all over the body, antibiotic treatment is necessary to prevent the condition from worsening in these young pigs which can lead to dehydration and/or systemic spread.

There is no need to call federal authorities, since no vesicular lesions are noted.

For the PowerPage’” on this topic, view [por Exudative epidermitis (Greasy pig disease)

For the PowerLecture™
on this topic, view
• Dermatology (5:37)

72
Q

Which of the following causes reproductive failure in pigs by an ascending infection of the reproductive tract?

  • Eperythrozoon suis
  • Toxoplasma
  • Leptospira interrogans
  • Parvovirus
  • E. coli
A

Answer: E. coli

Explanation
The correct answer is E. coli. Other infectious agents that ascend the reproductive tract causing metritis and reproductive failure in pigs include Streptococci, Staphylococci, Actinomyces spp., Pseudomonas spp., etc. The other answer choices listed cause reproductive failure via systemic infections. Other systemic agents causing reproductive failure include PRRS, pseudorabies, brucellosis, etc.

PowerLecture: Reproduction

73
Q

You have arrived at an lowa farm with an acute outbreak. The farmer has lost 25 pigs in the last two days. The pigs are all from the same building and are from a group of 950 four-week old pigs. The pigs arrived on the farm approximately 8 days ago. Upon arrival to the farm, you perform a necropsy on 8 out of the 20 dead pigs available. Seven of the first eight pigs you necropsy have lesions similar to those seen on the attached photo. You then perform a quick walkthrough of the building and do not identify any other sick pigs. What should you do next?

  • Have the feed company add 400g per ton of chlortetracycline to the next batch of feed
  • Have the owner inject all remaining pigs in the building with ceftiour
  • Select five non-treated, acute live pigs from the rest of the group to euthanize and collect samples for a diagnostic workup
  • Continue performing a necropsy on the remaining 12 dead pigs
A

Answer: **

Explanation
The correct answer is to have the owner inject all remaining pigs in the building with ceftiofur. The photograph depicts a classical presentation for polyserositis. The top two differentials for polyserositis in four week old pigs would be Streptococcus suis and Glasserella parasuis. Because of the high mortality in only two days, Glasserella parasuis would be your top differential and suggests a true emergency situation. As seen in the case history, many times the rest of the pigs appear to be normal. The only way to try and stop the outbreak is to inject all pigs ASAP. Although adding 400g per ton of chlortetracycline may be effective in preventing an outbreak, it is not the correct choice at the time of an outbreak. Feed delivery may be a week away, and even if feed could be delivered that same day, it would take three or four days before the pigs would get enough antibiotic via the feed. Immediate action is critical. There is no need to necropsy additional pigs, as a pattern has already been established. It is practically impossible to find an acute live pig in cases of Glasserella parasuis outbreaks; pigs are usually just found dead.

Note: ceftiofur is not as commonly used in Canada and should be used following confirmatory results on a bacterial culture/sensitivity.

***PowerLecture: Multisystemic Diseases

74
Q

Which organ system is typically LEAST affected by pseudorabies in pigs?

  • Respiratory system
  • Reproductive system
  • Central nervous system
  • Gastrointestinal system
A

Answer: Gastrointestinal system

Explanation
The correct answer is gastrointestinal system. Pseudorabies in pigs is caused by a herpes virus. Clinical signs vary in pigs of different age groups. Young neonates usually show CNS signs including anorexia, tremors, incoordination, blindness, paddling, etc. Morbidity and mortality of this age group can reach up to 100%.
Weaned pigs may have similar signs, but will also show respiratory signs such as coughing and dyspnea.

Mortality in this age group is much lower. Grower and finisher pigs predominantly show respiratory signs such as coughing, sneezing, and nasal discharge. Older pigs at breeding age show respiratory signs and may have reproductive failure. They do not show CNS signs.

There is no effective treatment for those infected with pseudorabies, but older pigs often recover on their own.

Vaccines are available for this disease. This disease has currently been eradicated from all commercial swine in the USA.

***PowerPage: Pseudorabies

***PowerLecture: Multisystemic Diseases

75
Q

A number of young growing pigs on a commercial hog farm are experiencing head tilt, incoordination, reduced weight gains, and weak rear limbs. Most have normal vital signs, and you suspect a nutritional deficiency. Which of the following deficiencies might cause such clinical signs?

  • Thiamine (vitamin B1)
  • Folic acid
  • Vitamin A
  • Sodium
  • Vitamin D
A

Answer: Vitamin A

Explanation
A shortage of vitamin A in the diet can lead to these signs in young pigs, especially an increase in middle ear infections, as also seen in turtles. In sows it can cause embryonic mortality and congenital defects in their offspring.

76
Q

What swine disease is a major worldwide cause of fetal death without signs of illness in the sow, and is controlled mainly by vaccination?

  • Swine influenza
  • Rotavirus
  • Porcine adenovirus
  • African swine fever
  • Porcine Parvovirus
A

Answer: Porcine Parvovirus

Explanation
Porcine Parvovirus affects seronegative sows exposed during the first half of gestation. Affected sows may return to estrus, fail to farrow despite being anestrus, have small litters, or have a high proportion of mummies.

Vaccines in the United States are inactivated.

***PowerLecture: Reproduction

77
Q

Which of the following is not a management measure for controlling swine colibacillosis?

  • Waiting until after a colibacillosis outbreak before administering iron injections
  • Commingling pigs of different ages
  • Vaccination for E. coli
  • Commingle sows and gilts during breeding and up to 4 weeks before farrowing
A

Answer: Commingling pigs of different ages

Explanation
The correct answer is commingling pigs of different ages. Pigs of different ages should not be mixed together. In addition to the options listed as answer choices, the management of swine colibacillosis includes keeping farrowing pens warm and dry, using enticing pig pumps, keeping piglets well fed with swine milk replacer, and spiking milk with porcine spray-dried plasma.

78
Q

You are called to a sow farm to investigate an abortion outbreak. The owner has 600 sows and is concerned because 5 sows aborted overnight. Upon arrival you find that all 5 sows that aborted were at least 95 days pregnant. Everyone seemed fine 2 days ago but yesterday a few sows started to cough and were off feed. Today there are a lot more sows coughing. The aborted sows all have temperatures of 105.0 - 106.5F (40.6-41.4 C). Which of the following samples is most important in helping you confirm your diagnosis?

  • Collect 2 aborted fetuses from each sow
  • Collect a random sample of blood samples from sows (aborted and not aborted)
  • Collect blood samples from aborted sows only
  • Euthanize a sow and collect a complete set of tissues
  • Collect nasal swabs from all aborted sows
A

Answer: Collect nasal swabs from all aborted sows

Explanation
The correct answer is collect nasal swabs from all aborted sows. In this case, the sudden onset of coughing that is highly contagious is highly suggestive of swine influenza virus. Swine influenza virus does not go systemic. It causes abortion by creating a systemic illness (fever), but the virus does not spread via the blood. The virus is not found in the blood or the aborted fetuses. A necropsy of an affected sow is not necessary to confirm the diagnosis as nasal swabs of acutely affected animals are great diagnostic specimens.

***PowerLecture: Respiratory Diseases

79
Q

In the U.S., swine tuberculosis is most commonly associated with exposure to materials (feed, water, bedding) contaminated by what animals?

  • Dairy cows
  • Feral swine
  • Domestic swine
  • White tail deer
  • Birds
A

Answer: Birds

Explanation
The correct answer is birds. Most swine TB outbreaks today are caused by avian TB and traced back to usage of surface water or bedding that has been contaminated by birds. Swine TB is very rare in the U.S. due to modern hog production practices. Bovine TB is still present but is not very common either. Deer can serve as a source to contaminate water but this is not as common.

80
Q

You are called to an organic swine farm to address a problem with piglet performance. The owner reports he is losing a large number of pigs due to wasting. The pigs seem to do fine for about 3 weeks and then will start losing weight. Pigs are left on the sow for 4-5 weeks before they are weaned. Many of the pigs are in such bad shape by the time they are weaned they are not able to recover in the nursery phase. As you visit the farm you find one dead piglet. It appears to weigh just over 10 Ibs. You perform a necropsy and notice the small intestines to be extremely thickened. The owner thinks the pig is about 4 weeks old. As you look for other pigs you find 40% of them are thinner than expected. Several of them have a loose stool. No blood is noted on any stools. Sows seem to be eating well. All pigs are vaccinated for ileitis. What question should you ask the owner?

  • What is the PRRS status of the herd?
  • Have there been any new additions to the herd in the past 3 months?
  • Do you remove all antibiotics from the feed 3 days before and 3 days after vaccinating for ileitis?
  • When are pigs vaccinated for ileitis?
  • Are pigs vaccinated against PCV2?
A

Answer: When are pigs vaccinated for ileitis?

Explanation
Your next question for the farmer should be “When are pigs vaccinated for ileitis?” The clinical presentation of diarrhea, extremely thickened small intestines, and wasting pigs is highly suggestive of Lawsonia intracellularis infection, commonly called ileitis. In modern pig production, ileitis vaccine is usually administered in the mid-to-late nursery stage (6 - 8 weeks of age) as clinically the disease becomes apparent when pigs are >12 weeks of age. In this case, because the farmer raised the pigs without antibiotics and most likely they are outdoors (organic production), these pigs are exposed to heavy doses of Lawsonia intracellularis organisms very early in life. This results in clinically affected pigs even as early as 3 weeks of age. Since the farmer is using a vaccine it is important to know right away if the timing of the vaccine is appropriate (at least 3 weeks before clinical signs are noted.

In this case, there is no need to ask about antibiotic use around vaccination as the farmer produces organic pigs and thus no antibiotics are allowed. PRRS does not cause thickening of intestines. PCV2 can cause wasting of pigs, but clinically affects pigs in the finishing phase (usually > 12 weeks of age). Ileitis is endemic in most, if not all, farms and therefore herd additions would not be a significant contributor to an acute outbreak.

81
Q

Regarding pigs, which one of the following disease agents is least likely to cause clinical disease in neonatal pigs, and occurs most frequently in pigs in the finishing stage (pigs >40 lbs)?

  • Isospora suis
  • Rotavirus
  • Trichuris suis
  • Cryptosporidium
  • Enteropathogenic E. coli
A

Answer: Trichuris suis

Explanation
Whipworms occur from weaning to adulthood, and result in feces that can be pasty, diarrheic, or occasionally mucohemorrhagic.

***PowerLecture: Gastrointestinal Diseases

82
Q

Several swine on a large commercial confinement farm have recently shown mucous membrane pallor and dark feces. Today there is a dead finisher (about 5 months old), and on postmortem you find large amounts of clotted blood in the stomach and duodenum. Which of the following causes is most likely?

  • Mycotoxicosis
  • Salmonellosis
  • NSAID toxicity
  • Stomach worms
  • Gastric ulcer
A

Answer: Gastric ulcer

Explanation
Gastric ulcers in growing swine are common. They occur mainly in the pars esophagea portion of the stomach.

Factors such as housing stress, finely ground feed and events that make pigs go off feed (feed delivery problems, respiratory disease outbreak, etc.) need to be investigated and problems corrected.

PowerLecture: Gastrointestinal Diseases