Small Ruminants Flashcards
What plant can cause “grass staggers” in sheep which lead to rabbit hopping rear limb gait, superexcitability, mustagmus and intentional head tremors (among other neuro/ataxic signs)
Canary grasses like folium, cano don and paspalum - genus phalaris
What in sheep can cause similar neuro and ataxic signs you would see if they ingested canary grasses (phalaris)
Hypomagnesemia - en happen when sheep graze lush pasture
What primarily causes bloat / rumen acidosis
Rich diets like alfalfa or forage , grain overload, those overeating or got into new feedstuffs, or those not adapted to the diet
What causes free gas bloat
Grain
What causes frothy bloat
Legume forage (alfalfa) more common, grain possible
What is the pathogenesis of rumen acidosis
Highly digestible chrbohudates like grain ingested in large amount ferment rapidly which drops the rumen ph, allows bacteria (lactobacillus) to further acidify the rumen which causes communal bacteria to die, osmotic pressure draws fluid into the rumen leading to systemic dehydration and shock - bacterial translocation happens due to damage rumen epithelium
What are clinical signs of bloat / rumen acidosis and when do they occur
Usually 6-36 hours after ingestion - colic, anorexia, neuro signs, abdominal distention (left), respiratory distress , toxemia, dehydration, diarrhea, death
How do you treat bloat
Orgogastric tube to relieve pressure - can give surfactant/oil, omen trouarization if in severe respiratory distress
How do you treat acidosis
Correct fluid/base disturbances and dehydration , NSAIDs for pain, rumen transfaunation, antimicrobials, thiamine supplementation
What clinical signs would you expect to see specific to an acidosis
Toxemia, dehydration, diarrhea, death
Define rumen transfaunation
Transferring when fluid with microbes + nutrients from a heathy animal to an animal with impaired rumen digestion
Why would thiamine supplementation help treat acidosis
Decreased thiamine allows for increased anaerobic metabolism which con worsen lactic acidosis - supplement thiamine to prevent
What comorbidities can occur due to rumen acidosis
Secondary polioencephalomalacia, liver abscesses, laminitis
What is polioencephalomalacia and what is often the cause in small ruminants
Thiamine deficiency causing bilateral neurologic signs - usually secondary to rumen acidosis and grain overload I can be due to diets that are low roughage high concentrate
How does a lack of thiamine lead to neuro signs (polioencephalomalacia)
Thiamine is necessary for ATP in the brain - without it, sodium and water accumulate leading to cerebral edema and necrosis of cerebral gray matter neurons
How does rumen acidosis lead to a thiamine deficiency
Thiamine produced by healthy rumen flora - with acidosis, thiamine producing bacteria go down and misfire using bacteria go up leading to deficiency
What are three possible differentials for a thiamine deficiency
Rumen acidosis, plant derived thiaminases ingested in bracken fern plants, or coccidia drug treatment with amprolium
What are clinical signs of polioencephalomalacia (a thiamine deficiency)
Bilaterally symmetric signs, central blindness, absent menace, intact PLR and palpebrals, opisthotonos, rigidity, nystagmus, head pressing, depression, recumbency
What is your top differential for bilateral neuro disease in small ruminants
Polioencephalomalacia - thiamine deficiency
What can help diagnose polioencephalomalacia in small ruminants post Morten
Edema and brain tissue that fluoresces under UV light
How do you treat polioercephalomalacia
Diane given slow IV or IM, Dexmethasone for edema
Define opisthotonos
Spasm of muscles casing backward arching of neck, back, etc
How can you differentiate between polioencephalomalacia and listeriosis in a small ruminant showing neuro signs
Polioencephalomalacia causes bilateral neuro signs , listeriosis cause, unilateral signs
What mostly causes listeriosis and when are uw more likely to see this
Spoiled or wet feed, improperly fermented silage, spoiled hay bales - most likely to see in winter
What is the pathogenesis of listeriosis in small ruminants
Animal ingests listeria monocytogenes through spoiled feed, the bacteria then crosses mucosal surfaces and invades any microabrasions - travels through axons of cranial nerves to CNS causing microabsesses and focal encephalitis
What are clinical signs of listeriosis
Unilateral cranial nerve signs / unilateral facial paralysis causing dropped jaw, dysphasia, absent palpebral reflex, drooling , heat tilt, circling , nystagmus, febrile , dehydration, recumbency
How do you treat listeriosis
Antimicrobials like oxytetracycline or penicillin, NSAID’s and fluid support
Are you more likely to see a fever with polioercephalomolacia or listeriosis
Listeriosis
What is contagious ecthyma in small ruminants
Orf/ sore mouth - parapoxvirus causing sores and crusts around the lips or on the mammary gland it from a nursing kid
What is the biggest reason you should remember contagious ecthyma
Can be zoonotic and cause painful skin lesions in people
How do you treat contagious ecthyma / orf
No treatment - disease is suf limiting and lasts 1-3 weeks, can resist in the herd for years
Orf (contagious ecythma) has a - morbidity and - mortality
High morbidity, low mortality
How do you diagnose of / contagious exthyma
PCR of crusts
What is caseous lymphadenitis and what is the causative agent
Bacterial disease causing subcutaneous abscesses in the head and neck lymph nodes - caused by corneybacterium pseudo tuberculosis (intracellular)
Otitis media causing a head tilt is usually towards
The affected side
What happens to saanen goats with papillomas
Often become squamous cell carcinomas
Why to outbreaks of cl often occur in sheep flocks
Bacteria (c. Pseudotuberculosis) an persist in soil and herds for years, often spread by shearing with infected Clippers
What clinical signs do you see with cl and when
2 weeks to 6 months after exposure - enlarged lymph nodes (submandibular, parotid , Supra mammary) filled with caseous material, could see systemic disease due to internal abscesses if severe (respiratory distress weight loss, etc)
How do you diagnose cl
Culture and serology
How do you treat cl
Lance and drain abscesses (be careful disposing contents - do not just lance in the stall ) / cull affected animals , systemic antibiotics can help prevent secondary infections
Can you vaccinate against cl
No - risk of adverse reactions and only decreases severity of disease (does not eliminate from herd)
What is OPP and CAE in sheep and goats
Ovine progressive pneumonia and caprine arthritis encephalitis virus - both retroviruses/ RNA viruses causing chronic disease
How do you treat OPP and CAE
No treatment - cull affected animals
How are OPP and CAE transmitted
Transmitted to lambs and kids through colosseum, then causes lifelong subclinical disease usually
What clinical signs can you see with CAE
Poly arthritis in adults, encephalitis in kids , chronic mastitis in adults causing hardbag
What clinical signs could you see with OPP in sheep
Pneumonia, poor doers (weight loss, lethargic, mastitis) - affects adults more than lambs
How do you diagnose OPP and CAE
Serology - positive antibody means active infection because this is a lifelong disease
When are you likely to see urolitriasis in sheep and goats
wethers, Males castrated young (less than 6 months) on high grain diet /rich legume hay that develop the calculi - also if diet has an improper mineral balance, usually at 1-3 years Old
Define urolithiasis
Formation of urinary calculi/stones in the urinary system
Describe the treatment and reoccurrence rate of urolithiasis
Usually doesn’t work and recurrence happens often - obstruction happens due to size of urethra and number of calculi formed
What are the most common sites of obstruction with urolitiasis
Urethral process and sigmoid flexure common
What are the most common calculi types formed with urolithiasis in males
Calcium or struvite
What are clinical signs of urolithiasis
Stranguria, tail flagging, dribbling urine, teeth grinding, lethargy , anorexia, recumbency
How do you diagnose urolithiasis in small ruminants
Azotemia, enlarged bladder on abdominal ultrasound, free abdominal urine on ultras and if bladder ruptured , radiopaque calculi on rads
How do you treat urolithiasis
Amputate the urethral process (where they get stuck), tube cystotomy, perineal urethrostomy , urinary acidifies / systemic support
What is a perineal urethrostomy and why would you do it
Surgery to make a permanent opening in the urethra for urine outflow - to treat polithiasis in males
Why is parasitism common in small ruminants herds
Significant resistance to common dewormers in the US
What ave common internal parasites in small ruminants
Coccidia, strongyles (like haemonchus), lungworms
Describe coccidia in young ruminants
Causes profuse diarrhea - 3 to 6 months old commonly susceptible
Describe the effect of haemonchus / barber pole worm in small ruminants
Severe anemia (pale famancha score ), bottle jaw (head and neck ventral edema), weight loss, diarinea
Describe lungworm infections in small ruminants
Causes coughing - diagnose with baermann exam
Describe what parasite control programs for internal parasites should look like in small ruminants and why
Should be targeted to avoid anthelmintic overuse - fecal parasite counts done before and after deworming to detect resistance, pasture rotation, routine feces removal, routine famancha scoring
What are common external parasites of small ruminants
Lice, mange mites (chorioptic mange)
Describe lice infestations in small ruminants
Musty in goats causes pruritis, patchy alopecia, requires multiple rounds of insecticide treatment to kill all life stages
Describe mange mites in small ruminants
Mostly in goats - causes alopecia and pruritis
Where do you usually find chorioptic mange mites in small ruminants
On legs, rarely ventral abdomen
What is the causative agent of Johne’S disease in small ruminants
Mycobacterium avium paratuberculosis
How are small ruminants infected with Johnes disease
Through contaminated milk or feces, trans placental if dam infected - either near the bacteria or develop a chronic disease state
What are clinical signs of John’s disease in small ruminants
Asymptomatic until 2-7 years old, chronic weight loss, diarrhea
How do you diagnose and treat Johnes in small ruminants
Serology ( fecal culture takes awhile ) - no treatment, cull animals and offspring
What is scrapie in small ruminants
Transmissible spongiform encephalopathy in sheep mostly causing progressive behavioral and neurologic signs
What is important to remember about scrapie in small ruminants
Reportable!
What causes scrapie
Prior that is ingested and invades lymphoid tissue then CNS causing spongiform degeneration
What are clinical signs of scrapie
Progressive over 6 months, behavior changes, intense pruritis, gait abnormalities, anorexia, weight loss, wool loss
How do you treat scrapie in small ruminants
No treatment - cull affected or exposed animals, entire here might be depopulated
What is bighead in sheep
Form of malignant edema caused by closhidium novyi type A
What is black disease and what is the causative agent, affecting sheep and cattle
Infectious necrotic hepatitis - caused by clostridium novyi type B
Describe the pathogenesis of black disease - what is it similar to?
Endosperm are ingested and lodge in the liver , liver dukes in sleep cause damage to the liver which causes the bacteria to release toxins that cause severe liver damage and red blood cell destruction - very similar to redwater disease
What are clinical signs of black disease in sheep
Sudden death with no clinica signs usually
How do you diagnose black disease
Large areas of damaged tissue in liver that are grey to black with a foul odor - post mortem
How do yo treat and prevent black disease
Usually isn’t treated, disease progresses too rapidly - prevent with the 7 way bacteria vaccine (2 doses)
What is the causative agent of overeating disease / pulpy kidney disease
Clostridium perfringens type D
What is the causative agent of overeating disease / pulpy kidney disease
Clostridium perfringens type D
Why is overeating disease also called pulpy kidney disease
Causes rapid carcass decomposition that causes pulpy kidneys on post Mortem
When are you likely to see cases of overeating disease
Mostly in sheep and goats under 2 years on a high grain ration or fattening lambs on rich pasture
If clostridium perfringens is a normal inhabitant of the git, why does overeating disease happen
Normal fora but causes disease after excessive ingestion of feed or grain
What are clinical signs of overeating disease
Decreased appetite, weakness, incoordination, diarrhea, nervous signs, death, can see glucosuria
How do you treat and prevent overeating /pulpy kidney disease
Prevent with 7 way bacterin vaccine - no treatment
What clinical signs are seen with yellow lamb syndrome
Icterus, weakness, acute death