Small Ruminant Diarrhea Flashcards
What is characteristic of Peste de Petits infection? What causes it?
- fever
- necrotic stomatitis
- gastroenteritis
- pneumonia
Paramyxovirus - related to rinderpest
What ruminants are most susceptible to Peste de Petits?
goats and sheep
How is Peste de Petits transmitted? What is a main source of infection?
close contact, inhalation, and ingestion of contaminated food
nasal and ocular secretions, saliva, urine, feces
- virus does not remain infectious for long
What signs are associated with Peste de Petits?
- profuse diarrhea - dehydration, emaciation
- increased RR, dyspnea
- abortion
- nodules around muzzle
What 5 postmortem lesions are associated with Peste de Petits?
- inflammation and necrosis of oral cavity and GIT
- emaciation
- erosive zebra stripes of intestine
- bronchopneumonia
- enlarged LNs
What are 4 options for diagnosing Peste de Petits? What samples are collected?
- virus isolation
- antigen detection
- serology
- rt-PCR
discharges, oral lesions, whole blood
What treatment is recommended for Peste de Petits?
no specific treatment
- control bacterial and parasitic complications
- supportive care
How is Peste de Petits controlled?
- IMMEDIATELY notify authorities
- quarantine
- movement control
- euthanize infected and exposed
- clean and disinfect premises
In what situations are Peste de Petits vaccines recommended? What 3 types are available?
outbreaks (ring vaccine + high risk) or endemic areas to control disease
- attenuated rinderpest vaccine
- homologous attenuated PPR vaccines
- recombinant vaccine
What are 4 characteristics of Rift Valley Fever?
- short incubation period
- fever
- high mortality in young
- abortion in adults
What causes Rift Valley Fever? What 3 cleaning supplies are able to inactivate it?
Bunyavirus
- lipid solvents
- detergents
- low pH
What ruminants are susceptible to Rift Valley Fever? How is it spread?
- lambs
- calves
- kids
- sheep
arthropod vectors - Culex, Aedes > Anopheles mosquitoes
What animals act as amplifying hosts for Rift Valley Fever?
ruminants - highly viremic, source for vectors
What are 2 additional possible routes of transmission of Rift Valley Fever other than mosquito vectors?
- direct contact with aerosols
- skin abrasion or wound in humans manipulating infective materials (farmers, veterinarians, butchers)
What is characteristic of Rift Valley Fever is small ruminants? What else is seen?
foul diarrhea
rapid onset of fever, weakness, icterus, mucopurulent nasal discharge, and vomiting
What signs are associated with Rift Valley Fever in lams and kids?
- newborn deaths
- high fever
- listlessness, anorexia
- high mortality
What signs are associated with Rift Valley Fever in cattle?
usually asymptomatic
- abortion
- fever, weakness
- anorexia
- diarrhea
What is the characteristic postmortem lesion associated with Rift Valley Fever?
hepatic necrosis - enlarged, yellow, friable, petechial hemorrhage
What signs are indicative of Rift Valley Fever in humans?
- often asymptomatic
- influenza-like illness - fever, headache, myalgia, vomiting with recovery in 2-7 days
- retinopathy
- hemorrhagic fever
- encephalitis
How is Rift Valley Fever diagnosed?
- viral isolation - tissue culture, animal inoculation in baby mice
- serology - complement fixation, ELISA
How can Rift Valley Fever be prevented?
- vaccination - attenuated, inactivated
- vector control - mosquito repellent, long shirts and pants, bed nets
- keep livestock at high altitudes
- animal housing controls
What is characteristic of Border Disease? What causes it?
hairy-shaker lambs - weak lambs with fatal fetid diarrhea, tremors, abnormal body conformation, hairy fleeces –> ewes typically show no signs of disease
Pestivirus ovis - transmitted horizontally and vertically
What does outcome of fetal infection of Border Disease depend on?
stage of fetal development
- > 85 days - immune system able to destroy virus, antibodies detectable
- <85 days - abortion, survival causes birth of hairy shaker lambs
What are 3 diseases that Clostridia cause?
- MUSCLE - Blackleg, malignant edema, Sord, swollen head
- LIVER - Black disease, bacillary hemoglobinuria (red water)
- GUT - lamb dysentery, Struck, Pulpy kidney, Braxy, Tetanus, Botulism
What 3 types of Clostridia cause enteric disease? Where are these bacteria found?
- C. perfringens type B - lamb dysentery
- C. perfringens type C - struck
- C. perfringens type D - pulpy kidney
soil and normal GIT microflora
What small ruminants are susceptible to Clostridial disease?
young animals and lambs in feedlots
- adults develop immunity due to frequent exposure to toxins
What causes lamb dysentery? What signs are associated?
C. perfringens type B
- sudden death
- abdominal pain
- passage of semi-fluid feces mixed with blood
What are 3 postmortem findings associated with lamb dysentery? What is seen microscopically?
- extensive hemorrhagic enteritis
- ulceration –> intestinal perforation –> peritonitis
- congestion and edema of mesenteric LNs
hemorrhagic enteritis and necrosis extending into the muscular layer and peritoneum
What 2 factors increase susceptibility to lamb dysentery? What acts as the source of infection? How is it transmitted?
- overdistension of stomach with milk
- handling infected lambs and then healthy ones
contaminated soil and dam’s udder
ingestion
What is characteristic of peracute lamb dysentery? What is seen in the acute form?
sudden death without premonitory symptoms
- diseased animal lags behind the flock
- recumbent
- stiff and painful movement
- stop suckling
- rise in body temp
- colic
- restlessness, irritable
- brownish red diarrhea tinged with blood
What are 5 postmortem lesions associated with lamb dysentery?
- hyperemic and ulcerated GIT - dark red periphery and yellow necrotic center
- blood-stained contents in intestines
- enlarged and edematous mesenteric LNs
- pale, large, and friable liver
- pale yellow kidneys
How is lamb dysentery diagnosed? In what 2 ways is this done?
demonstration of C. perfringens type B and its toxin in intestinal mucosa of dead lambs
- isolation and ID of microorganism - MacConkey agar from periphery of lesions
- serology - toxin-antitoxin neutralization test in mice
What ruminants are most commonly affected by pulpy kidney disease? What is infection associated with?
lambs (3-10 weeks old), kids > calves
overload to change in diet to large amounts of grains and carbohydrates –> C. perfringens type D
What are the 3 forms of pulpy kidney disease?
(milk colic, overeating disease)
- peracute - sudden death
- acute - salivation, coma
- subacute - neurological signs, mucoid diarrhea, loss of condition, weakness
What are 6 predisposing factors associated with pulpy kidney disease?
- excessive consumption of milk or feed with grain
- immunocompromisation
- heavy intestinal parasite infestation
- diet rich in grains and low in dry matter (hay, grass)
- slow peristalsis
- high volumes of starches, sugars, and proteins in the gut –> Clostridial overgrowth –> increased toxins
What is the pathogenesis of pulpy kidney disease?
- overfeeding carbohydrates causes increased fermentation in the rumen
- acidosis occurs, which is a favorable media for the organism to proliferate
- epsilon toxin is released and circulated in the blood
- epithelial injury
- edema and hemorrhage in brain and kidney
What are the 4 major postmortem lesions associated with pulpy kidney disease?
- edema in serous cavities
- subendocardial hemorrhage of LV
- congested and soft kidney due to degeneration and autolysis (NOT IN ADULTS)
- symmetric encephalomalacia (NOT IN GOATS)
Pulpy kidney disease:
C. perfringens type D
What are 3 treatment options for pulpy kidney disease? How is it prevented?
- hyperimmune antiserum
- Sulfadimidine/Penicillin can prevent further proliferation of organisms and toxin production
- chelating agents
(recommended for all clostridial disease)
vaccination and reduction in food intake
What ruminants are affected by hemorrhagic enterotexmia? What causes it?
adult sheep, goats, and feedlot cattle - mainly yearlings (1-2 y/o)
C. perfringens type C
What is the characteristic sign of hemorrhagic enterotoxemia? Postmortem lesion?
struck - sudden death
hemorrhagic enteritis in jejunum and ileum with toxemia + abomasal mucosal membrane is hyperemic and covered with thick necrotized debris
What are the 2 major factors that predispose to struck?
- overeating
- enteritis favors the multiplication of the microorganism in the normal intestinal flora
Struck:
- sudden death
- hemorrhagic enteritis
A 1 y/o sheep is suffering from hemorrhagic diarrhea and scute abdominal pain. What is your diagnosis?
a. pulpy kidney
b. lamb dysentery
c. struck
C
A marked zebra striping is found in the intestine of an adult sheep. Before death, it has a fever and profuse diarrhea and necrotic lesions on the mouth and lips. What is your diagnosis?
a. PPR
b. CPD
c. Salmonellosis
d. RVF
A
Which of the following is caused by an Arbovirus and is transmitted by mosquitoes?
a. Johne’s disease
b. RVF
c. PPR
d. Cryptosporidiosis
B
