Large Animal FINAL

what are causes of chronic wasting in sheep and goats?

• competition

• dental disease

• maedi visna (sheep)

• caprine arthritis encephalitis (goats)

• paratuberculosis

• caseous lymphadenitis

• enzootic nasal adenocarcinoma

• GI parasites

• lameness

dental disease pathogenesis:

primary gingivitis→tooth loss and abnormal wear→secondary osteomyelitis

dental disease signs:

• >7 years old

• thin, BCS < 2

• slow eating

• decreased cub chewing

• swellings on jaw

• loss of incisors

dental disease treatment:

• rasp premolars and molars

• cull or euthanize

dental disease control:

• graze poor quality soil

• thistles and awns in hay

maedi visma (ovine progressive pneumonia) signs:

• adult sheep

• dyspnea/progressive cough

• exercise intolerance

• hard udders at lambing

• lymphocytic mastitis

• reduced repro performance

• reduced lamb growth and survival

• hind end ataxia and paresis/paralysis

• circling, head tilt

• tremor of lips

• arthritis

maedi visma (ovine progressive pneumonia) pathogenesis:

virus targets macrophages, stimulates lymphocyte proliferation in mammary tissue, lungs, CNS, and joints

maedi visma (ovine progressive pneumonia) transmission:

• aerosol

• colostrum

• milk

• in utero

• blood contaminated needles and instruments

• semen

maedi visma (ovine progressive pneumonia) diagnosis:

• ELISA

maedi visma (ovine progressive pneumonia) pathology:

• large, tanned, highly cellular, firm, heavy lungs

• esophageal imprint on lungs

• mucous in trachea

maedi visma (ovine progressive pneumonia) treatment:

euthanize

maedi visma (ovine progressive pneumonia) control:

• serology on adults

• cull

caprine arthritis encephalitis is caused by:

• caprine arthritis encephalitis virus

• small ruminant lentivirus

caprine arthritis encephalitis transmission:

• body secretions

• colostrum

• milk

• milking equipment

• in utero

• blood contaminated instruments

caprine arthritis encephalitis signs:

• arthritis and bursitis in carpus, stifle, scapula, occipital joint

• hard udder with little milk

• posterior paresis that can progress to tetraparesis

• torticollis

• progressive pneumonia

caprine arthritis encephalitis diagnosis:

• serology

caprine arthritis encephalitis pathology:

• synovium inflamed, thickened, scarred

• eroded cartilage

• lung, CNS, and udder affected with lymphoid follicles and scarring

caprine arthritis encephalitis treatment:

• NSAIDs

• euthanasia

caprine arthritis encephalitis control:

• serology

• separate young and old

• heat treat colostrum and milk

paratuberculosis is caused by…

mycobacterium avium paratuberculosis

• type I: sheep

• typer III: sheep and goats

paratuberculosis transmission:

• fecal oral

• milk and colostrum

• in utero

paratuberculosis diagnosis:

• fecal culture

• serology or milk ELISA

• post mortem

paratuberculosis pathology:

thickening of distal ileum, dilated lymphatics, enlarged ileocecal and mesenteric lymph nodes

paratuberculosis control:

• test and remove

• vaccinate

caseous lymphadenitis is caused by…

corynebacterium pseudotuberculosis

corynebacterium pseudotuberculosis transmission:

• direct contact

• coughing

• fomites

• contaminated feed, water, bedding

caseous lymphadenitis pathogenesis:

enter through skin→move to regional lymph node→form abscesses which break and drain (external or pulmonary)→infectious discharge

sheep caseous lymphadenitis abscess appearance:

onion skin (lamellated)

what are the most common lymph nodes where caseous lymphadenitis occurs?

• parotid

• submandibular

• cervical

• prescapular

caseous lymphadenitis diagnosis:

• location of abscess

• culture

• abscesses in internal organs on post mortem

caseous lymphadenitis treatment:

• lance and drain

• iodine or chlorhexadine

caseous lymphadenitis control:

• monitor

• cull

• disinfect shearing injuries

• vaccinate lambs prior to exposure (12-16 weeks of age)

enzootic nasal adenocarcinoma signs:

• nasal tumor

• upper resp noise

• increased inhalation effort

• facial deformity, neuro signs

• 100% fatal

enzootic nasal adenocarcinoma transmission:

nasal secretions

enzootic nasal adenocarcinoma diagnosis:

• post mortem

• PCR of nasal secretions

enzootic nasal adenocarcinoma treatment:

• euthanize

periparturient

3 weeks before parturition and 3 weeks after

pregnancy toxemia pathogenesis:

insufficient energy in the diet to meet nutritional requirements of late gestation usually seen with more than one fetus

• transient hypocalcemia→encephalopathy

• mobilization of lipid stores→elevation in ketone bodies, accumulation of lipids in liver cells, impairment of hepatic function

• high levels of corticosteroids

• fetal death and maceration

• end stage renal and liver failure

pregnancy toxemia risk factors:

• thin BCS < 2.5

• fat BCS < 4

• competition

• poor water quality or quantity

• held off feed

• shearing

• inclement weather

pregnancy toxemia signs:

• grinding teeth

• not aggressive to get grain

• depression

• head pressing

• opisthotonus

• ± blindness

• tremors

• ataxia

• circling

pregnancy toxemia individual lab abnormalities:

• urine or blood ketones

• elevated liver enzymes

• elevated BHBA (>.8 mmol/L is subclincal threshold)

pregnancy toxemia flock lab abnormalities:

• moderate underfeeding: .8-1.6 mmol/L BHBA

• severe underfeeding: 1.6-3 mmol/L BHBA

• clinical: >3 mmol/L BHBA

pregnancy toxemia pathology:

• fatty liver

• dead fetuses

mild pregnancy toxemia treatment:

• 50 mL 50% dextrose IV

• isolate and provide grain

• 60mL glycol orally BID for 3-10 days

moderate-severe pregnancy toxemia treatment:

• 50-100 mL 50% dextrose IV

• fluids

• induce birth

• give 60mL calcium slowly

• antibiotics

• euthanize

vaginal prolapse individual risk factors:

• previous prolapse

• overconditioned

• multiple fetuses

• genetics

• short dock length

vaginal prolapse flock risk factors:

• poor quality forage

• crowding at feeder

vaginal prolapse treatment:

• epidural

• replace vagina

• vaginal spoon

• suture vulvar lips

gangrenous mastitis is caused by:

• staph aureus

• mannheimia hemolytica

• pseudomonas aeruginosa

gangrenous mastitis signs:

• febrile

• depressed

• may be lame or down

• udder cold, blue, bloody secretion

• affected half of udder will slough off

gangrenous mastitis treatment:

• support

gangrenous mastitis control:

• reduce stocking density (>2 sq meters per ewe)

• control orf

• tilmicosin at weaning or 1 month prior to lambing

causes of abortion in small ruminants:

• chlamydia abortus

• coxiella burnetti

• toxoplasma gondii

• campylobacter jejuni (mainly sheep)

• campylobacter fetus (sheep)

• iodine deficiency

all infectious agents are zonotic

chlamydia abortus signs:

• fresh abortion

• placentitis

• stillbirths, weak neonates, open ewes and does

chlamydia abortus transmission:

aborted fluids

chlamydia abortus control:

• oxytetracycline every 18-21 days after 80 days gestation

• vaccinate

coxiella burnetti (Q fever) signs:

• fresh abortions, stillbirths, weak lambs/kids

• placentitis

coxiella burnetti (Q fever) transmission:

• aerosol

• fetal fluids

• milk

• feces

coxiella burnetti (Q fever) control:

• tetracycline

• vaccine

toxoplasma gondii signs:

• mummies, abortions, stillbirths, weak lambs/kids

• coteledonary lesions

toxoplasma gondii control:

• cat and rodent control

• feed monensin or decoquinate during last 14 weeks of pregnancy

campylobacter transmission:

• aborted fetuses, placenta

• carrion birds

campylobacter signs:

• lesions on liver of fetus

• mild placentitis

• edematous cotyledons

campylobacter control:

• vaccine for C. fetus

iodine deficiency abortion signs:

• late term abortions, stillbirth

• weak lambs/kids

• large thyroids and less hair on aborted fetuses

iodine deficiency abortion control:

place iodine on skin of ewes weekly

polioencephalomalacia in small ruminants is caused by…

thiamine deficiency

polioencephalomalacia risk factors:

• high level of grain

• molasses

• bracken fern, horsetail

• high sulfur

polioencephalomalacia signs:

• stiff, stilted gait

• opisthotonus

• cortical blindness

• may go down

• die within 1-2 days

• cerebral/cerebellar edema and brain fluoresces with UV light

polioencephalomalacia treatment:

• thiamine

• dexamethasone

listeriosis risk factors:

• silage/haylage with pH > 5

• contamination with dirt/manure

• forage fed on ground

listeriosis pathogenesis:

entry via bloodstream or trigeminal nerve→incubation→microabscesses in brainstem

listeriosis signs:

• fever

• unilateral cranial nerve signs (circling, head tilt, facial paralysis)

• abortion

listeriosis treatment:

• oxytetracycline, penicillin, or TMS

• dexamethasone

• NSAIDs

• extended nursing care

listeriosis control:

• metaphylactic treatment with oxytetracycline

• remove from source of infection

• feed off ground

what small ruminant diseases are reportable?

• rabies

• scrapie

scrapie signs:

• intense pruritus

• increased grooming

• high stepping, stumbling, abnormal head carriage

• recumbency

foot disease complex includes:

• foot scald

• foot abscess

• foot rot

foot disease complex signs:

• lameness

• eat on knees

what pathogens cause foot scald?

• fusobacterium necrophorum

• ± benign strains of dichelobacter noduses

what pathogens cause foot rot?

• fusobacterium necrophorum

• dichelobacter noduses

what pathogens cause foot abscess?

• fusobacterium necrophorum

• dichelobacter noduses

• trueperella pyogenes

foot disease complex pathogenesis:

foot scald signs:

• interdigital skin macerated

• inflamed

• sole unaffected

foot rot signs:

• foot scald

• underrunning of sole

foot abscess signs:

• foot scald + deep involvement

• may include P2/P3 joint

foot disease complex treatment:

• 10% zinc sulphate foot bath

• oxytetracycline or tilmicosin

joint ill

polyarthritis in small ruminants

what pathogens can cause joint ill?

• erysipelothrix rhusiopathiae

• strep

• chlamydia pecorum

entropion treatment:

• penicillin injection around eye

• clips

• surgery

• repeated unrolling by hand

pinkeye/infectious keratoconjunctivitis is caused by what pathogens?

• mycoplasma conjunctivae

• chlamydia pecorum

• listeria

pinkeye/infectious keratoconjunctivitis treatment:

• oxytetracycline or tulathromycin if severe

causes of sudden death in lambs and kids:

• hypothermia/hypoglycemia complex

• pulpy kidney

• haemonchis

• copper toxicity

• urolithiasis

• pneumonia

hypothermia/hypoglycemia complex signs:

• increased mortality within first 72 hrs

• tucked up, depressed, empty

• down, cold, convulsing

hypothermia/hypoglycemia complex pathogenesis:

• lack of energy and cool temps

hypothermia/hypoglycemia complex risk factors:

• low birth weight (<3 kg), poor nutrition, abortion diseases

• dystocia

• mastitis, insufficient milk, poor mothering bond

• cold environment

when are brown fat reserves used up in lambs/kids?

5 hours

hypothermia/hypoglycemia complex treatment:

lambs and kids with no energy reserves must be given ____________________ before rewarming

an energy source

tubing a lamb steps:

1. sit on lap

2. measure tube to last rib

3. pass into mouth and encourage to swallow

4. feel tube in esophagus

5. slowly give colostrum