Bovine Diarrhea Flashcards
Diseases causing diarrhea in adult bovines, according to severity:
Diseases causing diarrhea in adult bovines, according to causative agents:
What are 2 common bacterial causes of diarrhea in cattle? What signs are associated?
- Salmonella - stress-induced, acute diarrhea, fever, dysentery, high mortality
- Mycobacterium paratuberculosis (Johne’s) - sporadic, chronic diarrhea with weight loss, long course, and no response to therapy
What are 3 common viral causes of diarrhea in cattle?
- Coronavirus (Winter Dysentery) - mature housed cattle, acute epizootic transient diarrhea and dysentery
- Rinderpest - plague form, erosive gastroenteritis and stomatitis, high morbidity and mortality
- MCF - erosive gastroenteritis, nasal/ocular d/c
What are the 4 most common parasites that cause diarrhea in younger calves on pasture? What signs are associated? How are they diagnosed?
- Ostertagia
- Haemonchus
- Trichostrongylus
- Oesophagostomum
acute/chronic diarrhea, dehydration, hypoproteinemia
fecal exam
What is a major fungal cause of diarrhea in cattle? What signs are associated?
Candida spp
younger cattle with chronic diarrhea with no response to treatment
What are 6 chemical causes of diarrhea in cattle? What signs are associated?
- arsenic
- copper
- mercury
- molybdenum
- poisonous plants
- nitrates
diarrhea, dysentery, colic, dehydration, toxemia, CNS signs
What nutritional deficiency is most commonly responsible for diarrhea in mature cattle? What causes it? What signs are associated?
copper
mature cattle on pasture with high levels of molybdenum
diarrhea, osteodystrophy, no systemic effects, hair color changes
What is the most common dietary cause of diarrhea in mature cattle? What causes it? What sign is associated?
simple indigestion caused by a change in ration (silage or grain) in feedlot cattle
subacute diarrhea, normal within 24 hours
How is small intestinal and large intestinal diarrhea differentiated? What indicates inflammatory or dietary etiologies?
- SI - watery, profuse
- LI - small volume, soft feces, excess mucus
blood, fibrinous casts
voluminous, soft, odoriferous
What is abdominal pain with diarrhea associates with in adults?
- Salmonellosis
- lead/arsenic poisoning
What is indicative of Johne’s disease?
chronic weight loss and diarrhea
What is indicative of copper deficiency as a cause of diarrhea? What causes it?
- moderate weight loss
- profuse diarrhea with normal hydration
- depigmentation of hair
diet high in molybdenum
What is a common sequelae of Salmonellosis diarrhea?
septicemia, toxemia, and fever
What are 4 blood analysis changes associated with diarrhea in mature bovines?
- hemoconcentration (elevated PCV)
- hypochlormia, hyponatremia, metabolic acidosis
- hyperkalemia
- increased BUN due to inadequate perfusion of kidney
When are parental and oral antibiotics recommended in cases of adult bovine diarrhea?
PARENTERAL - acute diarrhea, toxemia, fever
ORAL - subacute diarrhea with minimal systemic signs
What fluids are recommended for cattle with severe acidosis and diarrhea?
5% hypertonic bicarbonate give IV at 5-7 mL/kg at a speed of 100 mL/min
- severe dehydration = 100-150 mL/kg/day + KCl
What intestinal protectants are used in cases of diarrhea? What 3 effects do they have?
Kaolin and Pectin
- coat intestinal mucosa
- inhibit secretions
- increase bulk of feces
What 3 antidiarrheals are available for cattle? How do they work?
- Atropine
- Chlorpromazine
- prostaglandin inhibitors
antisecretories
What causes Johne’s disease? What are 4 characteristic signs?
Mycobacterium avium subsp paratuberculosis
- chronic fatal enteritis
- debilitating diarrhea
- progressive emaciatino
- thickening of intestinal mucosa
How is Johne’s disease transmitted?
fecal-oral
- feed/water contaminated by feces
- colostrum, milk, udder
- male and female reproductive tract
- calves commonly infected at birth and show signs ~ 2 y/o
What is the pathogenesis of Jonhe’s disease?
- organism penetrats ileum and colon, where it is phagoctyosed by macrophages
- organism multiples within macrophages until it kills the cell and is able to spread to other cells
- immune system recruits more macrophages and lymphocytes, resulting in cytokine release
- macrophages fuse together into granulomatous infection
- lymphocyte and macrophage infiltration causes visible thickening of the intestines, resulting in malabsorption –> lose body condition, milk production drops, diarrhea
(these cows are commonly anorexic despite good appetite)
What aged cattle commonly start showing clinical signs of Johne’s disease? What clinical signs are associated?
1-2 y/o
- weight loss, emaciation
- decreased milk production
- roughened hair coat
- thick diarrhea lacking blood
- intermandibular or ventral edema
- TPR normal
What is the characteristic postmortem lesion associated with Johne’s disease? What else may be seen?
thickened, corrugated wall of the distal small intestine
- dependent edema and fluid in body cavities
- discrete plaques
- enlarged mesenteric LNs
What are 4 options for diagnosing Johne’s?
- Johnin test - 0.2 mL PPD, SID
- isolation/identification –> slow growing, can take 5-14 weeks
- ELISA
- PCR
What stain is recommended for diagnostic Johne’s? What can be cultured?
Ziehl-Neelsen - clumps of small, strongly acid-fast bacilli
- feces
- thickened intestinal wall
- ileal, mesenteric, ileocecal LNs
What are 3 options for conventional vaccines for Johne’s?
- killed whole
- live whole attenuated
- modified whole cell killed and live
What are 3 disadvantages to conventional Johne’s disease vaccines?
- immune response induced by vaccines interfere with diagnosis of bovine tuberculosis
- antibody response interfere with ELISA
- have a minor effect in reduction of bacterial shedding
What liver fluke commonly infects cattle? What are 3 predisposing factors?
Fasciola spp
- low laying swampy area
- frequent floods
- stress - pregnancy, parturition
What acts as an intermediate host to liver flukes? In what season is this most common?
snails - L. cauillaudi and L. stegnalis
autumn, early winter
Liver fluke lifecycle:
How does acute and chronic fascioliasis compare?
ACUTE - sudden death due to hepatic insufficiency and hemorrhage into the peritoneal cavity (more common in SR)
CHRONIC - develops slowly as mature flukes move into the bile duct, causing cholangitis, obstruction, destruction of hepatic tissue, fibrosis, and hemorrhagic anemia (more common in large ruminants)
What clinical signs are associated with acute and chronic fascioliasis?
ACUTE - decreased appetite, dullness, weakness, pale MM, edema, enlarged liver, ascites, recumbency and sudden death within 48 hr
CHRONIC - anorexia, reduced growth rate, weight loss, decreased milk production, chronic diarrhea, bottle jaw, ascites, jugular pulsation, pale MM
What post mortem lesions are seen in cases of acute and chronic fascioliasis?
ACUTE - congested, swollen liver, perforated liver capsule and hemorrhage, small flukes seen
CHRONIC - large leaf liver flukes present in bile ducts and protruding above liver surface, calcification of bile duct walls, fibrotic liver parenchyma
How is liver fascioliasis diagnosed?
- samples - feces, liver, blood, serum
- fecal exam - direct, sedimentation shows oval, operculated greenish yellow cell wall
- biochem - hypoproteinemia
- hematology - decreased PCV, Hb, and RBC (normochromic or hypochromic anemia)
- histopath
What are some differential diagnoses of acute and chronic liver fascioliasis?
ACUTE - anthrax, enterotoxemia, acute pasturellosis
CHRONIC - Johne’s, Paramphistomiasis, intestinal helminths, nutritional deficiency (copper, cobalt)
What treatments are recommended for liver fascioliasis?
- flukicides - Fasenix, Triclazol, Coriban, Ivomec (for other endo and ectoparasites)
- symptomatic treatment
- supportive treatment
How does season alter fluke treatments?
SPRING/SUMMER - prevent eggs being laid on pasture, which can infect snails in the summer
AUTUMN - stop immature fluke migration and prevent liver damage
WINTER - kill adults in bile ducts, prevent liver damage and ill-thrift
How can fascioliasis be prevented?
FLUKE CONTROL - routine treatment, vaccination
SNAIL CONTROL - chemical, biological, and physical control
What vaccines are available for F. gigantica and F. hepatica infections? What effect do they have?
cysteine protease
glutatione S-transferase
decreases number of flukes in the liver
What causes malignant catarrhal fever? What 3 serotypes are there? What is the main source of infection?
Herpesvirus
- AHV-1 - wildebeest in Africa
- OHV-2 - domestic sheep and goats
- AHV-2 - nonpathogenic
nasal and ocular d/c +/- feces and semen
What animals typically act as carrier species for MCF? Which species have high mortality?
wildebeest, hartebeest, topi, sheep, goats
domestic cattle, WTD, Pere David’s deer
How are the serotypes of MCF transmitted?
- AHV-1 - in utero, aerosols, contaminated pastures
- OHV-2, CpHV-2 - aerosols, contaminated pastures
What are the 4 forms of MCF?
- peracute - sudden death
- head and eye - cattle
- intestinal - death occurs due to severe diarrhea
- mild - inoculated animals, recovery expected
How does head and eye form of MCF progress?
EARLY - red eyelids, bilateral corneal opacity, crusty muzzle and nares, nasal d/c, salivation
LATER - tongue and buccal erosions, swollen joints and superficial LNs, horn and hoof sloughing, incoordination, head pressing, nystagmus, hyperesthesia
What 4 postmortem lesions are associated with head and eye MCF?
- tongue and soft/hard palate erosion
- necrotic omasal and intestinal epithelium
- enlarged Lns
- necrotic larynx with diphtheritic membrane
What 4 diagnostics are used for MCF?
- histopath
- PCR
- virus isolation - AHV-1
- serology
What is prognosis of MCF like? What treatment is recommended?
poor –> survival is rare if clinically ill, recovered animals act as carriers
- supportive therapy
- antibiotics for secondary infections
How is MCF prevented?
separate infected and carrier animals from susceptible species
- keep cattle away from sheep and goats
- no vaccine available
In what cattle is winter dysentery most common? What are some clinical signs?
adult dairy cattle in northern climates housed indoors
- explosive diarrhea +/- hemorrhagic
- profound drop in milk production
- anorexia, depression
- mild respiratory signs
- high morbidity, low mortality
What causes winter dysentery? How is it transmitted? What are 5 predisposing factors?
bovine coronavirus (BCoV) - fecal-roal ingestion of feed or water contaminated with feces
- changes in diet
- cold temperatures - northern climate
- close confinement with high animal density
- poor ventilation
- concurrent infection
What is characteristic of winter dysentery?
acute onset of fluid diarrhea and profound milk production decrease
- dark green to black
What treatment is recommended for winter dysentery?
- fresh water, palatable feed, free-choice salt
- IV fluids
- blood transfusion
- isolate newly introduced cattle for 2 weeks
no vaccine available
What are 2 causative agents of hemorrhagic bowel syndrome? How does it manifest?
- Clostridium perfringens type A
- Aspergillus fumigatus
sudden onset of abdominal pain and obstriation progressing to sternal recumbency, shock, and death –> acute, localized, necrotizing hemorrhagic enteritis of small intestines leading to an intraluminal blood clot
(more common in dairy cattle)
What are some predisposing factors to HBS? What are 5 clinical signs?
high fermentable carbohydrate diet and feeding TM ration
- sudden anorexia and depression
- sudden and pronounced drop in milk production
- scant dark, jelly type feces
- abdominal distension and pain with kicking of the abdomen
- dullness and weakness progressing to recumbency
What treatment is recommended for cases of HBS?
surgery - localize affected loops and manually reduce and dislodge the blood clots +/-resection
+ fluid and electrolyte therapy
What are the 3 most common serotypes of bovine salmonellosis?
- S. dublin (D) - cattle specific
- S. typhimurium (B) - non-host adapted
- S. newport
ZOONOTIC
normal commensal in the GIT
What are 6 herd risk factors associated with salmonellosis?
- large herd sizes
- recycled water flush system
- lack of quarantine facilities
- rendered product use
- concurrent disease
- inadequate cleaning of calf-feeding utensils
What are 6 animal risk factors associated with salmonellosis?
- age - 3-6 weeks old
- starvation/nutritional deficiencies
- concurrent disease
- poor Ig levels
- transport and other stresses
- manure access
How is salmonella excreted?
- oronasal secretions
- milk
- manure
- urine
What are the 3 outcomes of salmonella infection?
- symptomless carrier - no secretion in feces or milk, infrequently present in feces and/or milk
- latent carrier - salmonella present, but not excreted
- acute carrier - salmonella in feces or milk
What are the 3 major groups of clinical signs associated with salmonellosis?
- septicemia - common in newborn calves, high fever, depression, death (C. dublin can cause CNS signs)
- acute enteritis - fever, putrid and watery diarrhea, colic, survival causes abortion, polyarthritis, terminal dry gangrene
- chronic enteritis - persistent or intermittent diarrhea, survival leads to osteoperiostitis, osteomyelitis
Salmonellosis:
Salmonellosis:
gangrene associated with survival of acute entertitis
What postmortem signs are associated with the different forms of salmonellosis?
SEPTICEMIA - submucosal petechial hemorrhage
ACUTE ENTERITIS - mucopurulent or hemorrhagic enteritis, watery intestinal contents with putrid smells containing mucus and blood, superficial necrosis, enlarged mesenteric LNs, thick GB walls, fatty degeneration of the liver, blood stained fluid in peritoneal cavity
CHRONIC - ulcerative colitis, bilateral bronchopneumonia and polyarthritis
What are 4 options of diagnostics used for salmonellosis? How can results be improved?
- bacterial culture from feces, blood, and bulk tank/mild filter
- antigen detection from PCR or DNA probe
- serological ELISA
- indirect - leukopenia, neutropenia, hyponatremia, increased fecal WBCs
serial cultures, pinch biopsy from rectal mucosa, test feces of others in the herd, examine water and food
What are 3 parts of herd diagnosis of Salmonella?
- serological tests - positive = fecal culture in enriched media every 15 days
- test water and food
- test other animals and humans if S. typhimurium is suspected
In what 3 ways are salmonella carriers diagnosed?
- fecal cultures of all housed cows in 14 day intervals
- repeat examination on the day of calving - swab feces and vagina
- combination of fecal culture and serology to improve results
What 4 treatments are recommended for Salmonella?
- antimicrobials - Ceftiofur, TMS, Gentamycin, Amikacin
- supportive fluid and electrolyte therapy
- oral astringents and protectants - Bismuth subsalicylate
- parenteral NSAIDs
What should be done in cases of Salmonella outbreaks?
- handle all animals as if they are shedding
- reduce water and feed contamination
- clean equipment with chlorhexidine
- clean boots and mats with orthophenyphenol
How is salmonella infection controlled?
- prevent introduction - purchase replacement stock from direct sources, quarantine purchased animals for 4 weeks, prevent wild birds and rodents from accessing cattle feed stores
- minimize spread - identify carriers and treat or cull, prophylactic treatment in water, isolate infected animals, prevent feed and water contamination, dispose infected material, all-in all-out
- proper animal transportation - penned and fed hard food 5 days before shipping, prophylactic feeding antibiotics, disinfecting
- vaccination - live, attenuated, or low virulence strain > killed, autgenous of dam AND calf
Which of the following is NOT a cause of diarrhea in adult cattle?
a. chronic fascioliasis
b. Johne’s disease
c. salmonellosis
d. acute fascioliasis
D
A 5 y/o cow suffering from chronic diarrhea and bottle jaw. What is your diagnosis?
a. chronic fascioliasis
b. Johne’s disease
c. BVD
d. acute fascioliasis
A
This intestinal lesion was taken from a 7 y/o cow suffering from chronic diarrhea in a postmortem exam. What is your diagnosis?
a. chronic fascioliasis
b. Johne’s disease
c. salmonellosis
d. HBS
B
