Poultry & Exotics

Question 1

Which of the following clinical signs would you expect in a rabbit with a gastric trichobezoar?

a. Vomiting
b. Weight loss
c. Pruritus
d. Diarrhea

Answer 1

b. Weight loss

Trichobezoars (hair balls) get stuck in the stomach of rabbits and cause anorexia, weight loss, and scant stool production. Rabbits cannot vomit. Pruritus usually is not the predisposing factor to development of trichobezoars but rather, decreased gastrointestinal motility. Trichobezoars can be treated medically with supportive care and syringe feeding of a high-fiber food. Ideally, you want these to pass without surgery.

Question 2

A boa constrictor presents to you for weight loss, vomiting, hemorrhagic diarrhea, and anorexia. The snake is housed with herbivorous turtles, which all seem to be healthy. What pathogen should you be suspicious of?

a. Aspergillus spp
b. Plasmodium spp
c. Citrobacter spp
d. Salmonella spp
e. Entamoeba spp

Answer 2

e. Entamoeba spp

The correct answer is Entamoeba spp. Entamoeba invadens is a protozoal organism that causes severe gastrointestinal signs and death in snakes. Turtles act as carriers for the protozoa but are clinically unaffected. Diagnosis is based on identification of trophozoites or cysts in fecal smears or histologic sections. Metronidazole is the treatment of choice. Turtles and snakes should not be housed together.

Question 3

An adult budgerigar presents sitting on the floor of its cage. It has a history of polydipsia, weight loss, and progressive left leg lameness. What is your highest suspicion for what may be causing these signs?

a. Teflon toxicity
b. Renal adenocarcinoma
c. Bumble foot
d. Lead toxicity

Answer 3

b. Renal adenocarcinoma

The correct answer is renal adenocarcinoma. A mass in the renal parenchyma of a bird will compress and compromise the function of the ischiatic nerve, causing a unilateral leg lameness. We would be unlikely to see unilateral lameness with lead toxicity. Bumblefoot could affect one foot, but would not cause polydipsia. Teflon toxicity causes acute death in birds.

Question 4

Which of these is the most common cause of seizures in the adult ferret?

a. Intracranial neoplasia
b. Idiopathic epilepsy
c. Hepatic encephalopathy
d. Hypocalcemia
e. Hypoglycemia

Answer 4

e. Hypoglycemia

The correct answer is hypoglycemia. Hypoglycemia secondary to insulinoma is the most common cause of seizures in the adult ferret. Keep in mind, a prolonged seizure can actually cause hypoglycemia, so the finding of low blood glucose in a seizuring ferret does not necessarily confirm a diagnosis of insulinoma. Idiopathic epilepsy has not been reported in ferrets. Hypocalcemia and hepatic encephalopathy can cause seizures, but are not as commonly reported as hypoglycemia.

Question 5

Which of these diseases of chickens causes progressive paresis and can lead to paralysis of one or more extremities?

a. Renal carcinoma
b. Fowl plague
c. Newcastle disease
d. Marek’s disease

Answer 5

d. Marek’s disease

The correct answer is Marek’s disease. Marek’s disease can affect the sciatic nerves and can cause vasogenic brain edema which contributes to clinical signs described. Renal tumors can cause paresis/paralysis but would be expected to be unilateral.

Question 6

You are primarily a food animal veterinarian, and your client asks you to perform a necropsy on his son’s lizard. You cautiously agree to perform a necropsy and identify white chalky nodules in multiple joints. Additionally, there are multiple pinpoint white foci in the kidneys. Given these findings, you recall your reptile lectures and come to a conclusion as to what happened to this lizard. What is your diagnosis?

a. Aspergillosis
b. Hypovitaminosis A
c. Metabolic bone disease
d. Gout

Answer 6

d. Gout

The correct answer is gout. The key to this question is to realize that there is probable uric acid deposition in the joints, which would be indicative of gout. Gout occurs when there is an inability to excrete uric acid or an overproduction of uric acid. Metabolic bone disease would cause osteopenia and fibrous osteodystrophy. Aspergillosis can cause white plaques, but you would not expect them to be chalky and in the joints. Hypovitaminosis A does not affect joints.

Question 7

A person comes to your clinic and asks if it would be okay to regularly bathe their precious 8-foot python in the bathtub. What zoonotic agent would you want to warn her about?

a. E. coli
b. Yersinia pestis
c. Salmonella
d. Cryptosporidium

Answer 7

c. Salmonella

The correct answer is Salmonella. All reptiles are considered to be carriers of Salmonella. Therefore, strict hygiene and handling is advised. Also note that reptilian cryptospridium is NOT zoonotic (C. serpentis, host-specific).

Question 8

A client brings in her rabbit, which acutely went down in the hind limbs after playing with the owner’s daughter yesterday. On physical exam, the rabbit is dribbling urine and has no withdrawal in the hind legs. Forelimbs are normal. What do you suspect?

a. Vertebral fracture
b. Fibrocartilagenous embolism
c. Vertebral luxation
d. Hansen’s type I disc herniation
e. Hansen’s type II disc herniation

Answer 8

a. Vertebral fracture

The correct answer is vertebral fracture. Fractures in the caudal lumbar region frequently occur when rabbits are not handled properly or are stimulated to jump around excessively. Fractures are much more common than luxations, disc extrusions, or emboli. The most common site of fracture is L7.

Question 9

You are presented with two young wild cockatoos that have immature, clubbed feathers and a malformed beak (see image). You suspect this is Psittacine Beak and Feather Disease (PBFD). Which test would you run to confirm your diagnosis?

a. A gram stain of the diseased feather pulp
b. A serologic test for antibody to herpesvirus
c. PCR probe of whole blood for circovirus DNA
d. PCR probe of whole blood for polyomavirus DNA

Answer 9

c. PCR probe of whole blood for circovirus DNA

The etiologic agent for PBFD is circovirus-1 and circovirus-2 so submitting a whole blood sample for DNA probe analysis is the best method to check for viremia.

Question 10

An adult cockatiel presents for shifting leg lameness and an inability to bend the toes. An aspirate from a swollen toe shows spindle-shaped crystals cytologically. What is your diagnosis?

a. Immune mediated polyarthritis
b. Visceral gout
c. Septic polyarthritis
d. Synovial gout

Answer 10

d. Synovial gout

The correct answer is synovial gout. This disease occurs when uric acid crystallizes in the synovium and causes lameness. The underlying pathophysiology is not completely understood, but renal disease is found in many affected birds; treatment generally consists of a low-protein diet, allopurinol, and addressing underlying renal disease. Visceral gout affects the surfaces of the visceral organs. Septic polyarthritis and immune-mediated polyarthritis would not show spindle-shaped crystals.

Question 11

Which of the following viruses has a latent phase within the trigeminal ganglion of chickens, allowing a clinically healthy chicken to carry this virus into a new poultry flock?

a. Infectious bronchitis virus
b. Infectious laryngotracheitis virus
c. Infectious bursal disease virus
d. Lymphoid leukosis virus
e. Fowl pox virus

Answer 11

b. Infectious laryngotracheitis virus

ILT is a herpesvirus with a latent phase in neural tissue.

Question 12

A client brings you a box turtle that he recently purchased and has been caring for. On exam, you see that the turtle’s eyelids are markedly swollen due to palpebral edema and nasal discharge. Which of the following questions would be most helpful in determining the cause of the turtle’s clinical signs?

a. What is the temperature in the turtle’s habitat?
b. What do you use for a light source and how many hours per day is it?
c. What area of the country did the turtle come from?

d. Are there other animals in the turtle’s enclosure?
e. What is the turtle’s diet?

Answer 12

e. What is the turtle’s diet?

The signs described are characteristic of Vitamin A deficiency (hypovitaminosis A). Vitamin A is a fat-soluble vitamin that acts as an antioxidant and helps growth and repair of tissues. It is important for proper function of the eyes, skin, and mucous membranes. Squamous metaplasia occurs in vitamin A deficiency and most commonly causes changes to the tear ducts. The cause of hypovitaminosis A is an inadequate diet; therefore, finding out about the turtle’s diet would be the most helpful information.

Turtles fed iceberg lettuce, an all meat diet, or a poor quality commercial diet are prone to developing a vitamin A deficiency. Vitamin A is present in high quantities in green leafy vegetables (especially dandelion greens), yellow and orange vegetables such as carrots and yellow squash, whole fish, and liver.

Question 13

A falconer presents his peregrine hybrid to you with the complaint of lethargy and weakness. You run a blood chemistry panel and CBC and these are the abnormalities: elevated AST, elevated CPK, low total protein and a low hematocrit at 22%. Some of the RBCs have a small, round to oval structure with a large vacuole forcing the nucleus to be displaced to one pole, resulting in a ‘signet-ring’ appearance. Your diagnosis is avian malaria and it is caused by which of following organisms?

a. Bartonella
b. Hemoproteis
c. Dirofilaria
d. Plasmodium

Answer 13

d. Plasmodium

The plasmodium trophozoite is a stage of the parasite that is seen as a large vacuole displacing the nucleus on microscopic examination of red blood cells in infected birds.

Question 14

You have confirmed the diagnosis of Chlamydophila psittaci in a group of birds. What is your treatment of choice?

a. Acyclovir
b. Nystatin
c. Itraconazole
d. Doxycycline

Answer 14

d. Doxycycline

The correct answer is doxycycline. Nystatin is used to treat candidiasis. Acyclovir is an anti-viral agent and would be ineffective in this situation. Itraconzaole is used to treat avian apergillosis. VetPrep Note: Other antibiotics such as enrofloxacin and azithromycin are showing promise in the treatment of Chlamydophila but the classic treatment has been doxycycline. This may change to one of the other drugs in the future but public health officials may request the use of doxycycline in an outbreak situation because of it’s long time use and success.

Question 15

A Cockatiel hen, one of the owner’s prize egg layers, was found on the bottom of its cage and brought to your clinic on emergency. You check your records and see that the bird has had one previous reproductive problem with metabolic exhaustion but has always laid the egg successfully. On physical exam, you note the cloaca to be pink and dilated and abdominal palpation reveals a firm, round mass in the caudal abdomen. Your tentative diagnosis is that the bird is egg bound. Which of the following is the best treatment option?

a. Female Cockatiels are prone to adrenal tumors which prevents the normal release of prostaglandin during egg laying so immediate surgical removal of the egg should also include adrenalectomy
b. Prepare the bird for immediate surgery to remove the egg and perform an ovariohysterectomy
c. Provide the owner with a poor prognosis since unfortunately there is no viable treatment option for birds with this condition.
d. Medical treatment including analgesics, subcutaneous fluids, calcium administration, placing the bird in a warm, moist environment and reassess in 24 hours

Answer 15

d. Medical treatment including analgesics, subcutaneous fluids, calcium administration, placing the bird in a warm, moist environment and reassess in 24 hours

This is the best answer because taking a debilitated bird to immediate surgery will be extremely risky. Since the bird is a proven layer, it is best to stabilize this dystocia patient for its metabolic needs during the first 24 hours while monitoring its response. In many cases, the egg will be produced with medical treatment alone - especially since she has laid eggs successfully in the past. If the bird does not produce the egg within 24 hours, then surgical and non-surgical options for removal can be discussed. Cockatiels are not prone to anti-prostaglandin producing adrenal tumors.

Question 16

An adult chameleon was purchased by an owner one year ago and presents to your clinic with signs of anorexia, decreased activity, and lameness of its left rear leg. The majority of the new owner’s chameleon’s diet is cat food with occasional insects. The chameleon’s enclosure is temperature-regulated and has multiple features on which to climb and hide. Given the history and clinical presentation, which of the following answers is the correct diagnosis?

a. Metabolic bone disease
b. Articular gout
c. Hepatic lipidosis
d. Salmonella

Answer 16

b. Articular gout

The correct answer is articular gout. The key to this question is to note the feeding of cat food. Cat food is too high in protein for reptiles. Reptiles have an inability to process large amounts of protein, thus uric acid may subsequently deposit in the joints. Furthermore, chameleons are primarily insectivorous so the diet is inappropriate. Therefore, this is the most reasonable answer for this presentation in a captive chameleon on a sub-optimal diet. Cat food would not be expected to cause metabolic bone disease or hepatic lipidosis.

Question 17

A black mouse is presented for progressive, partial alopecia that started at the face and head and progressed to the trunk. The other mouse that it is housed with appears completely normal. The underlying skin is normal. What is the most likely cause for the alopecia?

a. Dermatophytosis
b. Barbering or chewing of the hair by its cagemate
c. Pattern alopecia
d. Ectromelia
e. Mite infestation

Answer 17

b. Barbering or chewing of the hair by its cagemate

The correct answer is barbering or chewing of the hair by its cagemate. The key to this question is that the underlying skin is normal and the cagemate is normal. Barbering commonly occurs with pigmented mice and is a behavioral occurrence.

Dermatophytosis or a mite infestation would cause crusting and scaling of the underlying skin, and the cagemate would most likely be affected as well. Ectromelia virus is a member of the family Poxviridae, and causes mousepox. Clinical signs include skin lesions and generalized disease.

Question 18

An owner presents with his sulphur crested cockatoo and his main complaints are “powder loss” and an irregular beak (see image). What disease should you test for?

a. Papillomatosis
b. Psittacine beak and feather virus
c. Parrot fever
d. Pacheco virus

Answer 18

b. Psittacine beak and feather virus

The correct answer is psittacine beak and feather virus. Powder loss in cockatoos is a common finding with this disease that you should be aware of. The beak and nails will also be affected. On physical exam, you can also expect feather dystrophy.

Pacheco’s virus does not cause the same clinical signs. Usually you will observe anorexia, depression, and it may cause death. With papillomatosis you will expect to find papillomatous lesions, which are not described in the question. Parrot fever is another name for Chlamydophila psittaci, which has non-specific clinical signs such as lethargy, respiratory signs, diarrhea, and decreased activity.

Question 19

You are visiting a small “back-yard” flock of chickens and examining the animals. You find several small gray-red mites (approx 0.7 mm) on several of the chickens which you recognize as Dermanyssus gallinae and Ornithonyssus sylviarum. How are these mites best controlled?

a. Control of both Dermanyssus gallinae and Ornithonyssus sylviarum relies on through insecticidal treatment of the environment
b. Dermanyssus gallinae is controlled primarily by thotough insecticidal treatment of the environment and Ornithonyssus sylviarum must be contorlled by application of approved pesticides to affected birds
c. Control of both Ornithonyssus sylviarum and Dermanyssus gallinae relies on application of approved pesticides to affected birds
d. Ornithonyssus sylviarum is controlled primarily by thorough insecticidal treatment of the environment and Dermanyssus gallinae must be controlled by application of approved pesticides to affected birds

Answer 19

b. Dermanyssus gallinae is controlled primarily by thotough insecticidal treatment of the environment and Ornithonyssus sylviarum must be contorlled by application of approved pesticides to affected birds

Dermanyssus gallinae (the common red mite) maintains the majority of the population in the environment so it is important to monitor and treat the environment including the cracks and crevices where mites tend to reside. Ornithonyssus sylviarum mites (northern fowl mites) spend their entire life cycle on the bird. This allows them to multiply more rapidly and makes it essential to treat the birds themselves to control the problem.

Question 20

The average life span of the avian red blood cell is _________?

a. 90-120 days
b. 120-150 days
c. 28-45 days
d. 14-28 days

Answer 20

c. 28-45 days

The correct answer is 28-45 days. This is significantly shorter than a mammalian red blood cell due to the higher metabolism of the cell.

Question 21

The 18-day duck embryo on the left (see image) is normal while the one on the right of the same age shows cervical lordosis, a shortened axial skeleton, and subcutaneous emphysema. Which management change would be most likely to reduce the incidence of such abnormalities?

a. Reduce or eliminate use of polychlorinated biphenols (PCBs)
b. Supplement ducks with calcium
c. Depopulate the flock and replace with pathogen free ducks
d. Supplement ducks with iodine
e. Reduce or eliminate organophosphate use

Answer 21

e. Reduce or eliminate organophosphate use

These deformities are associated with organophosphate insecticides, particularly parathion, which can cause several vertebral and long bone abnormalities as well as generalized stunting of embryonic development.

PCBs are mixtures of compounds released in combustion. They cause reproductive toxicity in avians by binding to estrogen receptors and altering thyroid and adrenal homeostasis. They do not cause specific fetal abnormalities.

Question 22

A 2-year old rabbit presents for scratching its ears. On physical exam you observe crusts and excoriations in its ears. Microscopic exam of the crusts reveals numerous mites. You prescribe ivermectin to treat which parasite in this rabbit?

a. Treponema paraluis cuniculi
b. Psoroptes cuniculi
c. Cheyletiella parasitovorax
d. Encephalitozoon cuniculi
e. Otodectes cynotis

Answer 22

b. Psoroptes cuniculi

Psoroptes cuniculi, the rabbit ear mite, causes severe crusting and inflammation in the external ear canals. Treatment is ivermectin or selamectin. Encephalitozoon cuniculi is a microsporidian parasite of rabbits that causes neurologic and renal disease. Cheyletiella parasitovorax is the rabbit fur mite and causes white flakes that resemble dandruff. Otodectes cynotis is the ear mite of dogs and cats. Treponema paraluis cuniculi is the causative agent of rabbit syphilis.

Question 23

What is the causative agent of Tyzzer’s disease in hamsters and rabbits?

a. Clostridium piliforme
b. Clostridium chauvoei
c. Clostridium difficile
d. Clostridium novyi

Answer 23

a. Clostridium piliforme

The correct is Clostridium piliforme. C. novyi causes infectious necrotic hepatitis (Black disease) in livestock. C. chauvoei causes Blackleg in cattle in sheep. C. difficile causes enterocolitis in swine.

Question 24

You are working as a relief veterinarian at an exotic animal practice, and a toucan is brought in for evaluation due to a history of poor feathering and an overgrown beak. Blood work shows elevated liver enzymes and bile acids. What disease common for this species must you rule out?

a. Cholangiohepatitis
b. Hepatic lipidosis
c. Hypocalcemia syndrome
d. Hemochromatosis

Answer 24

d. Hemochromatosis

The correct answer is hemochromatosis. Given the clinical signs, blood work results, and species, it is very important to consider hemochromatosis, as both toucans and mynah birds seem susceptible.

Question 25

An adult conure presents to you for progressive right sided lameness. On physical exam, you palpate an abdominal mass. What diagnostic test do you recommend?

a. Right leg radiograph
b. Urinalysis
c. Complete blood count
d. Abdominal radiograph
e. Serum biochemistry

Answer 25

d. Abdominal radiograph

The correct answer is abdominal radiograph. Based on the description, you should suspect a renal mass (carcinoma) causing progressive compression of the ischiatic nerve. A radiograph would be the best test of these choices to confirm that diagnosis. Radiographs of the right leg would rule out orthopedic disease, but would not show the primary mass. Urinalysis would most likely not show evidence of neoplastic cells.

Question 26

A pet bird is fed an all seed diet and it develops squamous metaplasia with white plaques in the mouth and poor feather quality. What deficiency should you suspect?

a. Molybdenum deficiency
b. Hypovitaminosis A
c. Hypovitaminosis D
d. Hypomagnesemia

Answer 26

b. Hypovitaminosis A

The correct answer is hypovitaminosis A. An all seed diet is deficient in vitamin A. Clinical signs include a blunted choanal papilla, rhinitis, sinusitis, and loss of skin and feather quality. Other causes of white plaques in the mouth include Candidiasis, trichomoniasis, capillaria, pox virus, and papillomatosis in birds.

Question 27

A 12-year-old female Scarlet Macaw from a large aviary presents for regurgitation, weight loss despite a good appetite, polyuria, and passage of undigested seeds in the feces. Which of the following is the most likely differential?

a. Pacheco’s disease (Herpes virus)
b. Proventricular dilatation syndrome
c. Capillaria
d. Hypovitaminosis A
e. Candidiasis

Answer 27

b. Proventricular dilatation syndrome

Proventricular dilatation syndrome, also known as PDS, PDD or Macaw wasting disease, can affect many species of birds in addition to macaws. Clinical signs of regurgitation, weight loss despite a good appetite, polyuria, and passage of undigested seeds are characteristic, but may also include neurologic signs. The histopathologic lesion is a lymphoplasmacytic ganglioneuritis. Pacheco’s disease causes acute liver necrosis and associated clinical signs, including sudden death. Hypovitaminosis A generally causes oral plaques and other types of squamous metaplasia. Capillaria is an intestinal parasite and may cause diarrhea or weight loss. Candidiasis is an overgrowth of yeast in the crop and may cause regurgitation but not the other signs.

Question 28

What is the causative agent of turkey coryza?

a. Bordetella avium
b. Ornithobacterium rhinotracheali
c. Pasteurella multocida
d. Haemophilus paragallinarum

Answer 28

a. Bordetella avium

The correct answer is Bordetella avium. Turkey coryza or avian bordetellosis is an acute respiratory disease of turkeys with high morbidity and low mortality. Clinical signs include nasal discharge, foamy eyes, and cough. Diagnosis is via isolation on MacConkey agar or serology. A vaccine is available but has mixed results. Antimicrobial therapy is usually unrewarding.

Question 29

An African Grey parrot fed an all seed diet develops seizures. Deficiency of which of the following is the likely cause of the seizures?

a. Magnesium
b. Phosphorus
c. Calcium
d. Vitamin A

Answer 29

c. Calcium

The correct answer is calcium. Hypocalcemia syndrome is common in African Greys and is seen when they eat seed diets deficient in calcium. The most common clinical signs are tremors and seizures.

Question 30

A 2-year old rabbit presents for scratching its ears. On physical exam you observe crusts and excoriations in its ears. Microscopic exam of the crusts reveals numerous mites. You prescribe ivermectin to treat which parasite in this rabbit?

a. Otodectes cynotis
b. Psoroptes cuniculi
c. Cheyletiella parasitovorax
d. Encephalitozoon cuniculi
e. Treponema paraluis cuniculi

Answer 30

b. Psoroptes cuniculi

Psoroptes cuniculi, the rabbit ear mite, causes severe crusting and inflammation in the external ear canals. Treatment is ivermectin or selamectin. Encephalitozoon cuniculi is a microsporidian parasite of rabbits that causes neurologic and renal disease. Cheyletiella parasitovorax is the rabbit fur mite and causes white flakes that resemble dandruff. Otodectes cynotis is the ear mite of dogs and cats. Treponema paraluis cuniculi is the causative agent of rabbit syphilis.

Question 31

A 1-year old female guinea pig presents for respiratory distress and weight loss. The guinea pig is housed in a 4x6 foot enclosure lined with newspaper. The guinea pig shares a cage with a 2-year old female rabbit that appears healthy. What is the most likely etiology?

a. Mycoplasma pulmonis
b. Bordetella bronchiseptica
c. Sendai virus
d. Teflon toxicity
e. Pasteurella multocida

Answer 31

b. Bordetella bronchiseptica

Many rabbits are inapparent carriers of Bordetella bronchiseptica. However, Bordetella causes primary respiratory disease in guinea pigs; therefore, guinea pigs and rabbits should not be housed together. Clinical signs of bordetella in guinea pigs include respiratory distress, weight loss, and sudden death.

Pasteurella multocida causes respiratory disease (“snuffles”) in rabbits but not guinea pigs. Mycoplasma pulmonis and Sendai virus are part of a complex of organisms that cause respiratory disease in rats. Teflon toxicity causes respiratory disease in birds but has not been reported to affect guinea pigs.

Question 32

A 3 1/2 year old castrated male ferret presents for episodes of lethargy. He has also been intermittently dragging the pelvic limbs. Which of these choices is a likely cause of these signs in this ferret?

a. Diabetes mellitus
b. Insulinoma
c. Renal carcinoma
d. Adrenal tumor

Answer 32

b. Insulinoma

The correct answer is insulinoma. This condition is common in ferrets and would cause bouts of lethargy. Intermittent pelvic limb weakness is another manifestation of systemic weakness secondary to hypoglycemia. Renal carcinoma is not common in ferrets. Adrenal tumors and diabetes mellitus usually are accompanied by different clinical signs.

Question 33

You are called out to examine a 4-year old dromedary who was castrated 10-days ago and is now not eating. The groin and prepucial area is extremely swollen. The camel is unable to stand and is drooling. His neck is extended and he appears to be unable to swallow. Which of the following is most likely responsible for these symptoms?

a. Rabies virus
b. Clostridium tetani
c. Methicillin-resistant Staphylococcus aureus
d. Trypanosoma evansi

Answer 33

b. Clostridium tetani

This camel is showing signs of tetanus. The organism was likely introduced into the body through the castration wound. It is recommended that camels are vaccinated against tetanus prior to castration. Reference: Trop Anim Health Prod. 2004 Apr;36(3):217-24.

While rabies may cause paralysis of the tongue and difficulty swallowing, the recent history of castration in this camel makes tetanus most likely.

Trypanosoma evansi is transmitted via biting flies and causes a slow wasting disease in camels.

Question 34

After a recent change in feed, numerous chickens in a flock have developed inappetence, ruffled feathers, and dark colored diarrhea. You perform a necropsy on a deceased chicken and find the middle and distal small intestine to be thickened and distended containing dark brown necrotic material; the intestinal mucosa has a diptheritic membrane. Which of the following treatment/management strategies is appropriate?

a. Dissolve copper sulfate and vinegar into the water
b. Add fishmeal, barley, and rye to the feed
c. Vaccinate breeders and progeny
d. Add penicillin to drinking water

Answer 34

d. Add penicillin to drinking water

The disease described is necrotic enteritis which is caused by Clostridium perfringens. C. perfringens A and C can cause acute enterotoxemia with sudden onset explosive mortality due to necrosis of the mucosa of the small intestine. Diagnosis is made based on clinical signs and necropsy findings and is confirmed by finding large numbers of short, thick, gram positive rods in mucosal scrapings. The disease should be distinguished from Eimeria brunetti and from ulcerative enteritis caused by C. colinum.

C. perfringens is nearly ubiquitous and usually only causes disease when intestinal microecology is disturbed (due to changes in feed or damage from other pathogens or toxins). This can be treated by addition of antibiotics to feed (virginiamycin, bacitracin, lincomycin) or water (bacitracin, penicillin, lincomycin). Avoiding drastic changes in feed and minimizing levels of fishmeal, wheat, barley, or rye in the diet can also aid in preventing necrotic enteritis.

Question 35

Which of these animals is not an induced ovulator?

a. Cats
b. Rabbits
c. Hamster
d. Ferrets

Answer 35

c. Hamster

The correct answer is hamsters. Cats, ferrets, and rabbits are all induced ovulators. Camelids are also induced ovulators.

Question 36

An owner brings in his prize winning American Fuzzy Lop rabbit to your clinic in mid-July due to a swelling on its neck. The client maintains approximately 25 rabbits of various breeds in an outdoor, open-air, fenced-in enclosure. You examine the unusual swelling and notice a hole in the center that is oozing pus. The owner agrees to anesthesia and surgical exploration. During surgery you are surprised to find and remove the larval structure pictured below. Your diagnosis of the larva is which one of the following?

a. A warble of the genus Hypoderma bovis, common in outdoor housed rabbits
b. The nasal bot larvae of white-tailed deer for which rabbits are the intermediate host
c. Cuterebra the larval form of the botfly
d. A mature oocyte of the encysted form of sarcocystis

Answer 36

c. Cuterebra the larval form of the botfly

The larva shown in the figure is classic for the cuterebra bot and rabbits housed in outdoor enclosures are susceptible to this type of lesion due to contact with flies and eggs deposited in their environment.

Adult, female, Cuterebra flies deposit eggs in and around caging, vegetation and animal burrows. Rabbits come in contact with the eggs as they pass through contaminated areas or by direct deposition of eggs on rabbit fur. Eggs hatch to a larval form in response to body heat and enter the body through the mouth or nares during grooming or, rarely, through open wounds. Within the rabbit, the larvae now migrate to subcutaneous locations around the head, body or neck. Here they develop and grow as a third instar larva and breathe through a breathing pore in the skin. This is the stage most clients will seek medical attention for their rabbits. If left unattended, in approximately 30 days the larva matures, exits the skin, falls to the ground, pupates and becomes an adult bot fly.

Question 37

A 16-year old budgerigar presents with progressive unilateral paresis of the right leg (see image). There is normal flexion and extension of the hip joint with decreased flexion, extension, and sensation below the knee. The remainder of your skeletal and neurologic examination is unremarkable. Which of the following is most likely in this bird?

a. Renal neoplasia
b. Botulism
c. Lead toxicosis
d. Intervertebral disc disease
e. Marek’s disease

Answer 37

a. Renal neoplasia

The signalment and progressive unilateral paresis are most suspicious for renal neoplasia of budgerigars. Affected birds develop paresis due to pressure exerted on the sciatic nerve by a renal tumor. There is typically normal flexion and extension of the hip joint with decreased flexion, extension, and sensation below the knee as described here.

Disc disease is uncommon in birds. Lead toxicity can lead to peripheral neuropathy and paresis but typically there are more multifocal or other accompanying signs such as polyuria/polydipsia, gastrointestinal signs, wing droop, head tilt, or convulsions. Marek’s disease typically affects younger animals. Botulism typically presents with flaccid paralysis of the legs, wings, and neck.

Question 38

Which of the following is the causative agent of fowl cholera?

a. Reticuloendotheliosis virus
b. Pasteurella multocida
c. Mycoplasma gallisepticum
d. Chlamydophilia psittaci

Answer 38

b. Pasteurella multocida

The correct answer is Pasteurella multocida. The bacterium is a gram negative rod. It causes fever, mucoid discharge from the mouth, diarrhea, petechia, ecchymoses, increased pericardial and peritoneal fluid, and death. The chronic form of the disease usually causes localized disease. Diagnosis is based on identifying the organism from samples in conjunction with clinical signs. Vaccines are available for prevention of the disease. Sulfa antibiotics are used for treatment.

Question 39

Which of the following agents has been associated with transmission from infected laying hens into eggs to initiate foodborne illness in people?

a. Chlamydophila psittaci
b. Salmonella enterica serotype Enteritidis
c. Avibacterium paragallinarum
d. Salmonella pullorum
e. Newcastle disease virus

Answer 39

b. Salmonella enterica serotype Enteritidis

Enteritis in humans may be associated with consumption of raw or improperly cooked eggs harboring this bacterium.

Question 40

You are examining a turkey flock and note that many young turkeys appear depressed and are huddling with ruffled feathers. You note mucoid, blood-stained diarrhea and perform a fecal exam and see multiple Eimeria oocysts. Which treatment recommendation would be best for this flock?

a. Add copper sulfate and vinegar to water
b. Add amprolium to water
c. Vaccinate all breeders
d. In-ovo vaccination
e. Salinomycin in feed

Answer 40

b. Add amprolium to water

The condition described is coccidiosis and the cause is Eimeria based on the fecal findings. There are many different Eimeria species that can infect poultry. Different species of Eimeria typically parasitize different regions of the intestine.

Coccidiosis in turkeys can be treated with Amprolium or Sulphonamides (ie Sulphaquinoxaline). Salinomycin is a coccidiostat but is toxic to turkeys, even at low doses. Ionophores such as lasalocid and monensin are coccidiostats that are used for prevention of coccidiosis in turkey growers.

Copper sulfate is sometimes used to treat fungal infections (thrush). There is a commercial vaccine available that consists of low doses of sporulated oocysts that can be given to day-old chicks. Prevention of infection by anticoccidial drugs is generally the preferred control method.