sheep, goats, and cattle II Flashcards
Other names for Bacillus anthracis
”Woolsorter’s disease”, “splenic fever”, “charbon”, “milzbrand”
C/S of anthrax
hyperthermia, anorexia, depression, listlessness, tremors, peracute deaths and hemorrhage
Bloody secretions in urine, feces, milk
Usually fatal within 1-3 days, esp in sheep and goats, but subacute/chronic state may occur
C/S of brucellosis in sheep
B. melitensis in ewes: usually self-limiting; 3rd trimester abortions
B. melitensis in rams: orchitis or pneumonia
B. ovis in sheep: epididymitis, testicular atrophy; rarely, abortion
C/S of brucellosis in goats
B. melitensis: 3rd trimester abortions; systemic disease can occur
B. abortus: rare, but can be transmitted if in close contact with cattle
C/S of brucellosis in cattle
B. abortus: abortions with retained placenta after the 5th month; orchitis, epididymitis; lameness may occur
Why are ruminants particularly susceptible to brucellosis
Higher levels of erythritol (sugar alcohol), esp in placenta and male genitalia
Which brucella spp are zoonotic?
B. abortus and B. melitensis (not B ovis)
Most important cause of ovine abortion in the US
Campylobacter
Dx of campy
Gull wing rods
C/S of Clostridium perfringens
Diarrhea
C. perfringens releases what type of toxin
Epsilon toxin
What are pathognomonic in acute cases of C. perfringens type D?
Hyperglycemia and glucosuria
Pathogenesis of C. perfringens
epsilon toxin causes neuronal death and shock through vascular damage and increasing gut permeability
Lesions of C. perfringens
subendocardial hemorrhage, pericardial effusion, plus extremely necrotic, soft kidneys (not always); goats tend to have more GI lesions rather than systemic (like sheep)
Pathogenesis of tetanus
exotoxin is a multiunit protein consisting of tetanospasmin (neurotoxic) and tetanolysin (hemolytic)
Toxin diffuses retrograde through motor neurons; inhibits release of glycine and GABA (blocks inhibitory neurons)
Which two organisms cause foot rot
Dichelobacter nodosus, Fusobacterium necrophorum
3 forms of Listeria in ruminants
- Encephalitis – most common form in ruminants
Can affect cranial nerves
Rapid death often occurs - Placentitis with abortion – usually results in late-gestation abortion; adult female may be asymptomatic
- Septicemia with hepatitis and pneumonia – may occur in neonatal lambs
Lesions in Listeriosis
microabscesses of midbrain are characteristic with encephalitic form
Septicemic form: microabscesses throughout viscera
Which Mycobacterium spp do sheep, goats, and cattle get?
Cattle TB: M. bovis
Sheep TB: M. bovis or M. avium
Goat TB: M. bovis, M. avium, or M. tuberculosis
c/s of mycobacteriosis
primary sites of infection are respiratory (M. bovis) or GI (M. avium) systems; weight loss is common
Q fever c/s
usually asymptomatic in ruminants; abortion, stillbirth, endometritis, mastitis, infertility and weak lambs can occur
Transmission of Q fever
very stable in the environment; free-living or arthropod cycle; especially concentrated in placental tissues; shed in milk, urine, feces, and oronasal secretions
Multiple spp of ticks are reservoirs
Zoonotic transmission of Q fever
Most common mode of transmission in humans is inhalation of infectious aerosols directly from birth fluids of infected animals or via inhalation of dust contaminated with dried birth fluids or excreta
Greatest concern in pregnant and immune-compromised humans
A single organism can cause disease
What kind of virus is Jaagsiekte (pulmonary adenomatosis)
RNA retrovirus
Lesions found in Jaagsiekte
small adenomas/adenocarcinomas throughout the lungs
Pathogenesis of Jaagsiekte
histologic changes caused by uncontrolled proliferation of type II pneumonocytes
Another name for Ovine Progressive Pneumonia (OPP), what kind of virus
RNA retrovirus. Maedi Visna
Lesions and c/s of Maedi Visna
pulmonary adhesions, ventral lung consolidation; mastitis; degenerative arthritis; meningeal edema, leukoencephalomalacia
weak, unthrifty, weight loss, dyspnea, tachypnea, pneumonia; ataxia, tremors, paresis; mastitis common
Most important viral dz of goats
CAE (Caprine arthritis encephalitis virus)
What kind of virus is CAEV
retrovirus
C/S of CAE
Most commonly: progressive arthritis in goats > 6 months old- swollen, painful carpal joints; pneumonia may occur in older animals; “hard udder” syndrome
Also causes neuro signs in kids 2-6 months old: unilateral weakness progressing to hemi- or tetraplegia (lower motor neuron disease); head tilt, blindness
Lesions of CAE
severe synovial hyperplasia with inflammatory cell infiltration; demyelination and inflammation in brain/spinal cord; lungs gray and do not collapse
What kind of virus causes Pseudorabies
Suid herpesvirus-1
C/S pseudorabies
: rapid course, usually fatal
Intense pruritis, alopecia, swelling, abrasions
Neurological signs: stamping, head-pressing, circling, CP deficits, nystagmus, strabismus, progresses to coma and death
Is pseudorabies reportable?
Yes
What virus causes Orf?
Poxvirus
Orf is most commonly seen where?
Commissures of mouth
How to prevent BSE
Don’t feed ruminant protein to ruminants
Which breed of sheep is esp susceptible to scrapie?
Suffolk
BSE c/s
hyperesthesia, nervousness, difficulty negotiating obstacles, reluctance to be milked, ataxia, and tremors, weight loss, decreased milk production; terminal state by 3 months after onset
Which animals most affected by Crypto
Young calves
Most important intestinal parasite of small ruminants
Haemonchus
C/S of Haemonchus infection
anemia, weight loss, decreased milk production, poor wool growth, “bottle jaw” due to hypoproteinemia
When does shedding of Haemonchus increase?
During parturition (spring rise)
PPP for esophagostomum
6 weeks
c/s of esophagostomum infection
Penetrate large intestinal mucosa, occasionally deeper areas near serosa
Inflammation results in caseous nodules that eventually mineralize
3 types of lungworms
Dictyocaulus, Protostrongylus, Muellerius
Which lungworm has a direct life cycle?
Dictyocaulus
Which lungworm has an indirect life cycle?
Protostrongylus, Muellarius (require snail intermediate host)
Which is the only lungworm in cattle?
Dictyocaulus
Which cestode has triangular eggs
Monensia
Fringed tapeworm
Thysanoma actinoides
Which louse is intermediate host of Thysanoma?
Psocid louse
Cysticercosis occurs due to larval form of which worm?
Dog tapeworm (taenia hydatigena and echinococcus granulosis)
Intermediate host of trematodes
Snails
Which mites are reportable? (3)
Sarcoptes, Psoroptes, Psorergates
Which 2 lice can affect ruminants?
Mallophagia, Anaplura
2 ticks seen in ruminants
Ixodidae (hard shell), Argasidae (soft shell)
Nasal bots are caused by which organism
Oestrus ovis
Screwworm g/s
Cochliomyia hominivorax
Sheep ked g/s
Melophagus ovinus
B-mannosidosis of goats manifests how?
Carpal flexion and pastern hyperextension; deafness with many musculoskeletal deformities
What is spider leg syndrome, and in which sheep breeds do you see it?
Hereditary chondrodysplasia, primarily in Suffolk and Hampshires
Which side is abomasum most commonly displaced?
L
What is frothy bloat caused by?
ingestion of green legumes and leguminous hay or grain
What does copper deficiency in pregnant ewes cause?
Enzootic ataxia
What copper toxicity cause?
Acute hemolytic anemia
What does thiamin deficiency cuase?
Polioencephalomalacia
