Bovine Pathogens Flashcards

Question

Clostridium botulinum

Answer 1

produces a toxin that blocks acetylcholine release by binding the presynaptic membrane, this causes progressive motor paralysis and generalized progressive weakness. Death usually occurs due to respiratory paralysis. The bacteria often proliferate in decomposing animal or plant tissue.

Answer 2

Eimeria (12 species identified in cattle, 3 that cause clinical disease); summer and winter varieties. Diagnosed using McMaster's technique. Treat with monensin. Nervous coccidiosis - heat stable

Answer 3

also know as screwworm. Large metallic blue-green colored fly. Females lay hundreds of eggs at the edge of fresh wounds on the cow; larvae hatch approximately 24 hours. As the larvae eat the living tissue, they create a huge wound. Screwworm larvae then fall off and pupate, completing their life cycle in approximately 21 days. This fly is reportable!!!

Answer 4

Result of Bovine Viral Diarrhea infection

Answer 5

Post-milk teat dip to prevent mastitis. Types: Strep agalactiae,

Answer 6

se cutaneous excoriated granulomas. Large, ulcerative skin lesions resembling infected granulation tissue and lymphangitis may occur in 2%–5% of cows. Location on the animal is variable but is often associated with skin trauma. Healing often occurs without treatment or with limited topical treatment in 2–4 wk. Abortion and mastitis may also occur.

Answer 7

parasitic hematophagous midge which causes skin disease as well as transmitting disease

Answer 8

parturition will occur within 24 hours

Answer 9

bovine lungworm and cause of verminous bronchitis. Often affects younger cattle more severely. Signs include cough and frequently tachypnea. The diagnosis is frequently suggested by the seasonal incidence although confirmation with fecal examination (Baermann) is important to achieve a definitive diagnosis. Treatment with an anthelmintic of clinically affected animals is usually effective. Direct lifecycle, no intermediate hosts.

Answer 10

Diet is enhanced with more anionic salts containing the strong ions chloride and sulfur and has decreased amounts of strong cations such as sodium and potassium. Used to help prevent milk fever. Cows become more acidotic which enhances parathyroid hormone function along with a better ability to utilize calcium.

Answer 11

most commonly in the tricuspid valve, in contrast of horses and SA where the aortic valve is most commonly affected. Animal may be septic as well and have swollen joints. Common cause of endocarditis in cattle are foot abscesses and other sites where pus and blood mix.

Answer 12

Intrauterine penicillin (after 30 days) or tetracycline or ceftiofur can be beneficial. Some prefer dilute povidone iodine or uterine lavage with saline to avoid negative impact of antibiotic residues in the milk. Prostaglandins can also be used to "short cycle" the cow which will aid in treating the endometritis.

Answer 13

Multifactorial but is mainly a result of poor housing and environment (poor sanitation and ventilation). Calves will have cranioventral consolidation and many times they have diarrhea as a result of being infected with Eimeria bovis.

Answer 14

Environmental contaminant. Pre-milking teat dips are useful for preventing such noncontagious disease as E coli, enterococcus, and Streptococcus sp.(other than S. agalactiae).

Answer 15

when dysfunctional, milk goes tot he rumen where it is fermented by rumen microbes and converted to volatile fatty acids and lactic acid. This results in rumen acidosis. Number of contributing factors, review feeding program

Answer 16

4-Methylpyrazole

Answer 17

liver fluke, lesions appear more as tracks and/or hemorrhage. Animals tend to present with abdominal pain or jaundice acutely. Chronically animals become anemic or anorectic.

Answer 18

episode, allergic disease. Usually, the animal will be housed indoors and be exposed to the allergen; going outside will improve his situation

Answer 19

also called acute bovine pulmonary edema and emphysema. It is one the atypical interstitial pneumonias (diffuse, non-septic lung disease). The lush plants are high in tryptophan wich is subsequently metabolized in the rumen to 3-methyl indole (toxic to the lungs).

Answer 20

Picornavirus Viral disease of cloven-hoofed animals characterized by fever and vesicles in the mouth and on the muzzle, teats, and feet Diagnosis: via antigen capture–ELISA or serotyping ELISA of affected epithelium Can be near 100% fatality Very contagious Vaccine available but countries fee of disease usually use slaughter and movement restrictions to control outbreaks

Answer 21

80% of foot disease involves the digits involves the rear digits, Additionally, approximately 85% of these involve the lateral aspect. This is because they bear the majority of their rear limb weight on the lateral claw in the hind. In the front, cattle put most of their weight on their medical claw.

Answer 22

10% Zinc sulfate baths

Answer 23

Vagal indigestion Treat with Poloxalene orally, this substance reduces surface tension and destabilizes the froth. In a pinch, you could also use cooking oil.

Answer 24

Gram-negative, obligate anaerobic bacterium that is a component of the normal rumen microflora. necrotic laryngitis. metritis causes bacteremic spread of the organism which can go to the liver and release toxins leading to damage and potential abscess formation, typically yellow and spherical with irregular outlines. Affected livers condemned at slaughter. DIagnosis could be confirmed by culture of the liver. one of the main causes of footrot in cattle

Answer 25

flagellate protozoa inhabit mucosal surface of small intestine, attach to brush border, and absorb nutrients. Treat with Fenbendazole

Answer 26

horn fly, cluster around base of horns on cattle. Suck blood and other fluids. Heavy infestation can lead to lesions on the ventral midline. Lower feed conversion -\> economic loss. Can treat with insecticides or ear tags.

Answer 27

barber's pole worm, is very common parasite and one of the most pathogenic nematodes of ruminants. Adult worms attach to abomasal mucosa and feed on the blood. This parasite is responsible for anemia, oedema, and death of infected sheep and goats, mainly during summer in warm, humid climates

Answer 28

barber’s pole worm, large stomach worm, wire worm

Answer 29

now known as Actinobacillus pleuropneumoniae

Answer 30

Blood sucking genus of louse, and can cause severe anemia. The anemic calves become thin and more susceptible to diseases like pneumonia. 6 legs vs 8 of mites and ticks

Answer 31

test at 6000 ft and above, \<40 mmHg pressure is a good prognostic indicator for cattle \>12 months of age

Answer 32

Etiologic agent of thromboembolic meningoencephalitis (TEME) in cattle. Affects the cerebellum and brain stem, but can cause other signs of system disease such as pneumonia, laryngeal disorders, joint infections, metritis, orchitis, and conjunctivitis. This systemic infection may start int eh respiratory tract in young stressed, often transported, cattle. Early treatment with antimicrobial drugs such as tetracycline, penicillin, erythromycin, or sulfonamides can be effective.

Answer 33

disorder of the placenta - prognosis for the fetus and fertility of the cow poor

Answer 34

"cattle warble" treat with ivermectin in early fall

Answer 35

"heel fly" larvae migrate to submucosa of the esophagus and can impair swallowing and eructation treat with pour on macrocyclic lactone or systemic insecticide

Answer 36

Grass tetany, grass staggers, winter tetany, metabolic disease involving magnesium deficiency, which can occur in such ruminant livestock as beef cattle, dairy cattle and sheep, usually after grazing on pastures of rapidly growing grass, especially in early spring.

Answer 37

Virus can quickly kill bovine fetus, but as the Herpes viruses in many hosts, there are signs of severe inflammation throughout the fetus.

Answer 38

Mycoplasma and Chlamydia

Answer 39

caused by bovine herpes virus 1 transmitted by natural service, nosogenital contact, or mechanically by some flies. Characterized by vaginal lesions which progress to pustules and erosions or ulcers. Intrauterine inoculation of the virus (from bull) produces necrotizing endometritis and cervicitis

Answer 40

3-Methyl indole is a pneumotoxin produced by rumen microflora when cattle ingest large amounts of L-tryptophan in forage, resulting in atypical interstitial pneumonia.

Answer 41

(Na + K) - (Cl + S)

Answer 42

Causes reproductive problems in herd, hemoglobinuria To eliminate from herd, treat all animals with tetracycline to eliminate carriers and regularly vaccinate all cattle against this serovar Vaccine will prevent new carriers, but will not eliminate existing carriers. To be cost effective, they may need to mass treat dry cows and young stock using long-acting tetracline

Answer 43

mononuclear pleocytosis on CFS tap, CNS signs, increased number of monocytes and macrophages. Listeria is usually contracted from ingesting silage that has been stored at a pH \> 5.0 Can cause abortion, but the fetus is usually autolyzed to a significant extent, and there are often brain micro-abscesses present.

Answer 44

Penicillin

Answer 45

caused by rumen acidosis

Answer 46

Genetic disorder associated with spongiform changes int he brain and caused by a deficiency of Branched-chain ketoacid decarboxylase in Hereford and polled Shorthorn calves. It usually shows up at 2 to 3 days of age. This disease causes an encephalopathy.

Answer 47

gastrointestinal worm of tropical countries

Answer 48

High WBC (neutrophilia) and protein on CSF tap. Clinical presentation: diarrhea, fever, anorexia, stiff neck, hyperesthesia.

Answer 49

Anoplocephalid tapeworm found in young cattle. Their life-cycle involves oribatid mites which live in the soil and are ingested by the host. Generally considered non-pathogenic but may cause intestinal stasis. Eggs are rectangular or triangular

Answer 50

Bovine Keratoconjunctivitis, transmitted by flies (Stomoxys calcitrans, Haematobia irritans, Musca autumnalis - the most commonly implicated vector)

Answer 51

face fly - most commonly implicated vector for Moraxella transmission

Answer 52

cause of Johne's disease which results in chronic wasting

Answer 53

may be spread to young calves via milk. In very young dairy calve it can cause otitis media with aural discharge, head tilt, nystagmus, ataxia, and even facial nerve paralysis In older calves it causes respiratory disease and can cause arthritis and tenosynovitis. Mastitis, abortion and other signs can also be caused by M. bovis

Answer 54

aerosol spread

Answer 55

Genetic disease identified in Charolais cattle. Affect cattle are born with a deficiency in the enzyme phosphorylase. Presents as a result of exercise intolerance and collapse, elevated AST, CK, and LDH.

Answer 56

dog definitive host; causes abortion from 3-8 months of gestation and typically results in an autolyzed fetus. Frequently, there are granulomas in the brain.

Answer 57

cattle \<1 year, Eimeria spp. Coccidia produce nervous coccidiosis by elaboration of a heat-labile neurotoxin

Answer 58

act by inhibition of acetylcholinesterase, causing muscarinic signs such as hypersalivation, incoordination, and bloat. Acute cases can be treated with high doses of atropine or pralidoxime (2-PAM).

Answer 59

occurs in winter and spring following rapid infection with large numbers of L3 larvae from the heavily contaminated pasture. Egg counts in this scenario tend to be much high and clinical disease is most common in younger animals after weaning.

Answer 60

Cobblestone abomasum - occurs because larva undergo hypobiosis (larval inhibition) and lay dormant in the early fourth larval stage within the glands of the abomasum, forming the nodules. They resume development and emerge seasonally leading to severe signs outbreaks in autumn into winter and low egg counts Treat with benzimidazoles and ivermectin

Answer 61

Sodium exchanges for hydrogen in the renal tubules Paradoxic aciduria can commonly occur in cows in situations where HCl trapping occurs in the abomasum such as when there is a torsion. This will lead to a hypochloremia. Dehydration also occurs and in the process of trying to conserve sodium to maintain blood volume, bicarbonate is retained and the cows become alkalotic. Then the cow's cells exchange hydrogen from inside the cell and take in potassium to try and return to a normal pH. This results in hypokalemia; the kidney tubules then start using hydrogen (instead of potassium) to exchange for sodium and conserve sodium. This means that they are excreting hydrogen and this is paradoxic aciduria.

Answer 62

bacterial calf pneumonia - "shipping fever pneumonia" gram-negative bacterium

Answer 63

Typically occurs in the last trimester and abortion is characterized by a hemorrhagic condition of the placenta and fetus

Answer 64

intraerythrocytic protozoan parasites Transmitted by ticks - Rhipicephalus (Boophilus) Lesions (particularly with B bovis) include an enlarged and friable spleen; a swollen liver with an enlarged gallbladder containing thick granular bile; congested, dark-colored kidneys; and generalized anemia and jaundice. Most clinical cases of B bigemina have hemoglobinuria, but this is not invariably the case with B bovis. Other organs, including the brain and heart, may show congestion or petechiae Treatment: diminazene aceturate or imidocarb dipropionate

Answer 65

Thiamine deficiency, necrosis of cortical gray matter See low WBC and protein on CSF tap

Answer 66

an inherited defect in the metabolism of hemoglobin and its byproducts. In cattle, accumulation of aberrant porphyrins in the skin increases sensitivity to ultraviolet light. Autosomal recessive trait found in several breeds.

Answer 67

phosphorus levels less than 2.0 mg/dL will most likely result in hemolysis -\> lactating post-parturition cattle hypophosphatemia

Answer 68

one of the main causes of footrot in cattle

Answer 69

due to pericardial effusion

Answer 70

Tends to cause septicemia in dairy calves 4 to 8 weeks of age. Transmitted by carrier cow to neonates at birth via their milk. Cull carriers and vaccinate calves using a modified live S. dublin vaccine.

Answer 71

sick, febrile, and have abnormalities in the CBC compatible with endotoxemia (neutropenia or neutrophilia), and an increased plasma fibrinogen. In a severe outbreak, some cows would likely die.

Answer 72

dog definitive host, ruminant intermediate host; Carnivore infected by eating host with cysts in the muscle, sporocysts shed in feces which are subsequently eaten by cows. Sporocysts hatch and penetrate artery walls and hand out in endothelium to develop into sporozoites and eventually become merozoites at which time they invade muscle and encyst as sarcocysts. Clinical signs nonspecific: fever, anorexia, salivation, weakness, muscle fasciculations, and weight loss.

Answer 73

flesh flies

Answer 74

a reportable mite which induces severe pruritus and, as a result, may be economically devastating.

Answer 75

fibrinous pleuropneumonia

Answer 76

Bronchiolitis obliterans - there is typically a history of switching from a poor pasture to a lush pasture two weeks ago.

Answer 77

stable fly

Answer 78

Obligate pathogen of the mammary gland of cows; usually causes subclinical mastitis, but sometimes you may see high somatic cell counts and clinical signs with this organism. Perform a CAMP reaction to diagnose this organism.

Answer 79

Treat with Praziquantel

Answer 80

ocular parasite, remove manually and treat with 10% levamisole drops. Transmitted by face flies. The adult Thelazia live in the tear ducts and in the conjunctival sac. Thelazia larvae are regurgitated from the crop of the face fly while feeding on ocular secretions. The worm larvae irritate the eyes and lacrimation, photophobia, conjunctivitis, corneal ulceration, keratitis and small eyelid abscesses result.

Answer 81

neutrophilic pleocytosis on CSF cytologic examination

Answer 82

magnesium oxide

Answer 83

abortion (early embryonic death), protozoa, venereal, poor calving %

Answer 84

small stomach worm ~5 mm long develop and survive better in cooler conditions

Answer 85

Significant risk factor for abortion

Answer 86

Rhabdovirus - reportable since clinical signs are similar to FMD

Answer 87

Epidemic disorder of housed cattle, usually occurring in cold months and affecting 10-90% of adult cows. If fever occurs at all, is usually precedes the diarrhea phase. The disease is thought to be caused by coronavirus, and lesions involve the colon. In typical outbreaks, the disease runs its course in weeks and the herd becomes immune and recovers, although milk production may not recover to previous levels.

Answer 88

Brucella abortus, Mycoberterium avium ssp. paratuberculosis, Listeria monoctogenes, Salmonella dublin

Answer 89

"foot hill abortion' Important disease of heifers and newly introduced cows in California foothills. Fetus shows enlarged lymph nodes and spleen, destructive lesions tot he thymus and evidence of chronic granulomatous infection. Etiologic agent is unknown, but vector is a tick, Ornithodoros coriaceus.