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Flashcards in Bovine Pathogens Deck (114)
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1
Q

Abomasal perforation

A

results in acute septic peritonitis. Prognosis is grave. Clinical signs: dehydration, weakness, and expiratory grunt. Acute abomasal perforation through a single 1-2 cm ulcer occurs sporadically in young (2-4 month old) beef calves and the cause is unknown.

2
Q

Abomasal torsion biochem

A

hypochloremia, metabolic alkalosis, hypokalemia. As a result of the torsion, animals sequester HCl int he abomasum, get hypochloremia and metabolic alkalosis. Additionally, animals become dehydrates and try to maintain adequate blood pressure by conserving sodium through renal mechanisms. Because there is alkalosis, potassium is sequestered even more than usual in cells leading to hypokalemia. Normally kidney excretes some potassium but when insufficient potassium is available, in order to reabsorb sodium to maintain blood pressure, hydrogen ions are excreted rather than potassium which results in acid urine at h same time as metabolic alkalosis, a condition know as paradoxic aciduria.

3
Q

Achromotrichia

A

copper deficiency

4
Q

Actinobaccilus lignieresii

A

“wooden tongue” - IV sodium iodine+anitbiotics and change feed

5
Q

Actinomyces bovis

A

“lumpy jaw”, condition results from the entry of the normal rumen inhabitants into the body mandile (usual site) or maxilla through a break int he mucous membranes or teeth. It may be arrested with therapy using sodium iodine, antimicrobials or even isoniazid off-label, but the bony swelling seldom changes much, even if arrested.

6
Q

Akabane virus

A

insect-transmitted virus that causes congenital abnormalities of the CNS in ruminants. Affects fetuses of cattle, sheep, and goats. AsymptomatiPeak inceidence of disease seen if cattle are infected at 3 to 4 months of gestationc infection has been demonstrated serologically in horses, buffalo, and deer in endemic areas.

Bunyaviridae; transmitted by culicoides spp

common in tropical and subtropical areas.

Calves infected late in pregnancy may be born alive but unable to stand and may have flaccid paralysis of the limbs, disseminated encephalomyelitis on PM

7
Q

Anaplasmosis

A

Anaplasma marginale. Clinical signs: pale, icteric, and febrile. Key features: adults sick, resistant to clinical Anaplasmosis as calves. Never seen hemoglobinuria with Anaplasmosis because if is all extravascular hemolysis.

Tick-borne, treat with tetracyclines

8
Q

Animal African Trypanosomiasis

A

African animal trypanosomiasis (AAT) is a parasitic disease that causes serious economic losses in livestock from anemia, loss of condition and emaciation. Many untreated cases are fatal

protozoan parasites in the family Trypanosomatidae. Most trypanosomes are transmitted by tsetse flies

9
Q

Anopheles

A

mosquito responsible for transmission of Maralia

10
Q

Arcanobacterium pyogenes

A

Most common postpartum pathogen leading to endometritis

Can also cause footrot

11
Q

Bacillary hemoglobinuria (Clostridium novy type D)

A

hemoglobinuria, caused by germination of C. novyi type D spores in the liver after anaerobic damage by migrating liver fluke larvae. Can be prevented with vaccination.

12
Q

Bluetongue

A

Reovirus: Small midges or gnats are the main route of transmission of bluetongue virus, although it can also be transmitted sexually or transplacentally. C sonorensis is the main species responsible for transmission int eh USA.

13
Q

Bovine High-Mountain Disease (BHMD)

A

“Brisket disease” High-altitude pulmonary hypertension

14
Q

Bovine Leukocyte Adhesion Deficiency

A

an adhesion molecule defect that causes granulocyte and lymphocyte dysfunction and recurrent soft-tissue infections

15
Q

Bovine Leukosis Virus (BLV)

A

clinical lymphoma, ELISA for antibody to envelope glycoprotein gp51

16
Q

Bovine Respiratory Syncytial Virus

A

A virus classified as a pneumovirus in the Paramyxovirus family

characteristic “honking” cough

Diagnose for PCR

Treatment: antimicrobial therapy for secondary bacterial infection

17
Q

Bovine Viral Diarrhea (BVD)

A

flavivirus

most common in young cattle

most commonly diagnosed virus in bovine abortion cases

The pathology of BVD in the developing fetus is complex. Infection before insemination or during the first 40 days of pregnancy results in infertility or embryonic death. Infection between 40 and 125 days of pregnancy results in birth of persistently infected calves if the fetus survives. Fetal infection during the period of organogenesis (100–150 days) may result in congenital malformations of the CNS (cerebellar hypoplasia, hydrancephaly, hydrocephalus, microencephaly, and spinal cord hypoplasia). Congenital ocular defects have also been seen (cataracts, optic neuritis, retinal degeneration, microphthalmia). After 125 days of gestation, BVD may cause abortion, or the fetal immune response may clear the virus

18
Q

Brucellosis

A

abortion (rare), retained placenta, metritis, and lack of signs in younger animals. Abortion usually occurs in last half of pregnancy and the fetuses appear relatively normal but typically there are signs of severe inflammation, including placentitis.

Vaccinated animals have tattoos and ear tags in their right ear. The first letter fo the tattoo indicates the type of vaccine. The USDA “V shield” indicated vaccination. The number indicated the last number of the year of vaccination. The information of the ear tag indicated the state by the first two numbers and then the remaining characters are a specific identifier for the animal so that it can be traced if necessary.

19
Q

BST or rBST

A

given by injection to lactating dairy cows every two weeks to increase the amount of milk produced and to prolong lactation.

20
Q

BVD fetus aborted

A

anytime during gestation

21
Q

BVD fetus persistently infected

A

before 125 days of gestation

22
Q

BVD fetus with congenital deformities

A

infected between 90-150 days of gestation, half of these will die within first year of life. Most common congenital anomaly is cerebellar hypoplasia

23
Q

Campylobacter fetus ssp. venerealis

A

Main cause of bovine campylobacteriosis but is not shed in milk. The organism is an obligate parasite of the bovine genital tract and causes abortion. Infection usually results in temporary infertility or early embryonic death.

24
Q

Campylobacter jejuni

A

Emerging milk zoonotic pathogen

25
Q

Clostridium botulinum

A

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.

26
Q

Coccidiosis

A

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

27
Q

Cochliomyia hominivorax

A

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!!!

28
Q

Congenital microphthalmia

A

Result of Bovine Viral Diarrhea infection

29
Q

Contagious mastitis

A

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

30
Q

Corynebacterium pseudotuberculosis

A

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.

31
Q

Culicoides

A

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

32
Q

Dexamethasone for inducing parturition

A

parturition will occur within 24 hours

33
Q

Dictyocaulus viviparus

A

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.

34
Q

Dietary cation-anion difference

A

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.

35
Q

Endocarditis

A

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.

36
Q

Endometritis treament

A

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.

37
Q

Enzootic pneumonias

A

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.

38
Q

Escherichia coli

A

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

39
Q

Esophageal groove dysfunction

A

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

40
Q

Ethylene glycol toxicity treatment

A

4-Methylpyrazole

41
Q

Faciola hepatica

A

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.

42
Q

Farmers lung

A

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

43
Q

Fog fever

A

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).

44
Q

Foot and Mouth Disease

A

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

45
Q

Foot disease location

A

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.

46
Q

Footrot treatment

A

10% Zinc sulfate baths

47
Q

Frothy bloat

A

Vagal indigestion

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

48
Q

Fusobacteria necrophorum

A

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

49
Q

Giardiosis

A

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

Treat with Fenbendazole

50
Q

Haematobia irritans

A

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.

51
Q

Haemonchus contortus

A

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

52
Q

Haemonchus placei

A

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

53
Q

Haemophilus pleuropneumoniae

A

now known as Actinobacillus pleuropneumoniae

54
Q

Hematopinus sp.

A

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

55
Q

High Mountain Disease test

A

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

56
Q

Histophilis somni (Hemophilus somnus)

A

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.

57
Q

Hydroallantois

A

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

58
Q

Hypoderma bovis

A

“cattle warble” treat with ivermectin in early fall

59
Q

Hypoderma lineatum

A

“heel fly” larvae migrate to submucosa of the esophagus and can impair swallowing and eructation

treat with pour on macrocyclic lactone or systemic insecticide

60
Q

Hypomagnesemium

A

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.

61
Q

Infectious Bovine Rhinotracheitis

A

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

62
Q

Infectious Keratoconjunctivitis

A

Mycoplasma and Chlamydia

63
Q

Infectious Pustular Vulvovaginitis

A

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

64
Q

L-tryptophan in forage toxicity

A

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.

65
Q

Late gestation anionic diet calculation

A

(Na + K) - (Cl + S)

66
Q

Leptospira interrogans serovar Hardjo (type Hardi-Bovis)

A

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

67
Q

Listeria

A

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.

68
Q

Listeria treatment

A

Penicillin

69
Q

Liver abscesses at slaughter

A

caused by rumen acidosis

70
Q

Maple syrup urine disease

A

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.

71
Q

Mecistocirrus digitatus

A

gastrointestinal worm of tropical countries

72
Q

Meningitis

A

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

73
Q

Moniezia

A

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

74
Q

Moraxella bovis

A

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

75
Q

Musca autumnalis

A

face fly - most commonly implicated vector for Moraxella transmission

76
Q

Mycobasterium paratuberculosis

A

cause of Johne’s disease which results in chronic wasting

77
Q

Mycoplasma bovis

A

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

78
Q

Mycoplasma pneumonia

A

aerosol spread

79
Q

Myophosphorylase deficiency

A

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.

80
Q

Neospora caninum abortion

A

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.

81
Q

Nervous coccidiosis

A

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

82
Q

Organophosphate toxicity

A

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).

83
Q

Ostertagia ostertagii type I

A

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.

84
Q

Ostertagia ostertagii type II

A

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

85
Q

Paradoxic aciduria

A

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.

86
Q

Pastuerella multicoida

A

bacterial calf pneumonia - “shipping fever pneumonia”

gram-negative bacterium

87
Q

Pine Needle Abortion

A

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

88
Q

Piroplasmosis (Babesiosis)

A

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

89
Q

Polioencephalomalacia

A

Thiamine deficiency, necrosis of cortical gray matter

See low WBC and protein on CSF tap

90
Q

Porphyria

A

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.

91
Q

Postparturient hemoglobinuria

A

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

hypophosphatemia

92
Q

Prevotella melaninogenicus

A

one of the main causes of footrot in cattle

93
Q

Pulse paradox

A

due to pericardial effusion

94
Q

Salmonella dublin

A

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.

95
Q

Salmonella typhimurium

A

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.

96
Q

Sarcocystis cruzi

A

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.

97
Q

Sarcophaga

A

flesh flies

98
Q

Sarcoptes scabiei

A

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

99
Q

Shipping fever

A

fibrinous pleuropneumonia

100
Q

Silo filler’s disease

A

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

101
Q

Simulium

A

Black fly

102
Q

Stomoxys calcitrans

A

stable fly

103
Q

Streptococcus agalactiae

A

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.

104
Q

Taenia

A

Treat with Praziquantel

105
Q

Thelazia

A

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.

106
Q

Thromboembolic meningoencephalitis (TEME)

A

neutrophilic pleocytosis on CSF cytologic examination

107
Q

Treatment to increase rumen pH

A

magnesium oxide

108
Q

Trichomonas foetus

A

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

109
Q

Trichostrongylus axei

A

small stomach worm ~5 mm long

develop and survive better in cooler conditions

110
Q

Twinning

A

Significant risk factor for abortion

111
Q

Vesicular Stomatitis

A

Rhabdovirus - reportable since clinical signs are similar to FMD

112
Q

Winter Dysentery

A

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.

113
Q

Zoonotic pathogens in milk

A

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

114
Q

Epizootic Bovine Abortion

A

“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.