GI - bovine GI disease Flashcards
Where is 80% of water reabsorbed in the bovine GI tract?
In the small intestine
Opposite of horses who absorb most in large intestine
What is lost in acute diarrhoea and what is lost in chronic diarrhoea ?
Acute diarrhoea - loss of electrolytes
Chronic diarrhoea - loss of nutrients
How is diarrhoea diagnosed in cattle?
History - age, herd, duration, nutrition
Examine group, individual and faeces
What should you examine in a cow with diarrhoea?
Oral vacity
Perineal region
TPR
BCS
Pain
What is the biggest cause of coccidiosis?
Build up of parasite oocysts in the environment
Indoor house, insufficient bedding
What are the signs of coccidiosis?
Acute to chronic diarrhoea - smelly, greenish, mucoid
Poor weight gain in growing calves
What is the treatment for coccidiosis?
Self limiting usually
Can give diclazuril
What are the most important helminths that cause chronic dairrhoea?
Ostertagia
Liver fluke - fasciola hepatica
What 3 diseases does salmonellosis cause?
Enteritis
Abortion
Septicaemia
What are the 2 salmonella serotypes?
Typhimurium
Dublin
How is salmonella spread?
Faecal-oral
Conjunctival
Respiratory
What is the difference between salmonella typhimurium and salmonella dublin?
Typhimurium - exist in the environment or in different species and spill into cattle - fluctuate
Dublin - endemic, in cattle population at all times, cow host specific
What season is salmonella typhimurium peak incidence?
Autumn - associated with housing
How does salmonella dublin shed? How is it different between carriers?
Active carriers - shed for up to a year
Passive carriers - shed while exposed
Latent carriers - shed when stressed
What is salmonella dublin associated with?
Fasciola hepatica - liver fluke
How long is salmonella typhimurium and salmonella dublin carried for?
Typhimurium - 4 weeks
Dublin - years, with intermittent shedding
How is salmonella diagnosed?
Faecal culture
Histopath
Lesion culture
What is a notifiable disease that causes diarrhoea in animals?
Salmonella heheh got you
Which salmonella serotype is sensitive to most antibiotics?
Salmonella dublin
Salmonella typhimurium is much more resistant
What are the clinical signs of the enteric syndrome of salmonellosis?
Lethargy
Pyrexia
Milk drop
Diarrhoea
Pain, recumbency, death
What is the second most common diagnosed cause of bovine abortion in GB after neospora?
Salmonella
What does salmonella cause in calves?
Diarrhoea
Lethargy
Pyrexia
Inappetence
Sloughed extremities - peripheral gangrene
Death
How do you treat salmonellosis?
Systemic antibiotics - amoxycillin, trimethoprim/siulphonamides
Supportive care - fluids, diet
How can you prevent salmonellosis?
Closed herd
Isolate introductions for 4 weeks
Isolate sick animals
Clean buildings between occupancies
Vaccinate - bovivac S
What is the most important cattle viral disease in the UK?
Bovine viral diarrhoea virus
What is the genus of BVD virus?
Pestivirus
What are the two genotypes of BVD virus?
Classical form - BVDV 1
Severe acute BVD haemorrhagic syndrome - BVDV 2
What are the two biotypes of BVD virus?
Non-cytopathic - 90%
Cytopathic - 10%
How do the different biotypes relate to mucosal disease BVD?
Secondary infection of animals with the non cytopathic virus with the cytopathic virus
What is the key to the survival of the virus in bovine populations?
Naïve adult cattle with subclinical BVD producing persistently infected calves
What symptoms can naive adult cattle get from BVD?
Mild pyrexia
Diarrhoea
Reduced milk yield
Poor fertility, early embryonic death, abortion
What symptoms can naive calves get from BVD?
Immunosuppression - resp disease, diarrhoea, pyrexia
What does BVDV 2 cause?
Acute haemorrhagic enteritis and death
What do persistently infected calves with BVD get?
Poor growth rates
Immunosuppression
Mucosal disease - if they become infected with the cytopathic virus
So what are the two broad syndromes of BVD?
Acute infection followed by immunity
Persistant infection +/- mucosal disease
Why do persistently infected calves react so badly to the cytopathic BVD virus?
Because they gain immunotolerance to BVD in the womb so the body doesnt learn that the virus isnt self so doesnt mount an immune response
How do calves get congenital abnormalities from BVD?
If between 4-9 months there is an immune response in the foetus to the virus
How does the mucosal disease of BVD initially invade a herd?
If the virus mutates from the non cytopathic form to the cytopathic form then spreads through the herd
What are the clinical signs of mucosal disease in BVD cattle?
Oropharynx - ulcers, pain, ptyalism, hyperaemia
Muzzle - ulcers, cracked
Gut - ulcers, profuse homogenous diarrhoea
Feet - ulcers in digital cleft
Eyes - lacrimation, epiphora
Nose - mucopurulent discharge
Rapid loss of condition
How do you diagnose mucosal disease from BVD in cattle?
Clinical signs
PM exam - microvesicles/ulcers in GI tract
Lab testing
What are 3 notifiable diseases that are differential diagnoses for BVD/mucosal disease?
Food and mouth
Bluetongue
Rinderpest
What lab tests do you do for BVD/mucosal disease?
Antibody ELISA - testing for immune response
Antigen PCR - testing for virus
What will be the lab results for mucosal disease?
Positive antigen PCR but negative antibody ELISA - no immune response
What will the lab results be for vaccination against BVD?
Only positive antiBODY ELISA, not antigen PCR - not virus present but immune response
How do you eradicate BVD in the dairy herd?
Test bulk tank for antigens
If positive then test individual cows for antigens
Cull PI animals, vaccinate others
How do you eradicate BVD in youngstock?
Test 9-18month cohort pooled blood for blood antibodies
If positive for antibodies then means there are PI cows in herd infecting others
So if herd positive to antibodies then test individuals for antigens - if positive then cull
How do you monitor for BVD?
Do bulk milk antigen PCR quarterly
Test purchased stock
Annually test unvaccinated youngstock
How do you vaccinate for BVD? When do you do it?
Vaccinate with bovilis BVD from 8 months onwards
Or with bovela from 3months onwards
Must complete first course before first service - to prevent PI calves
When are cows most susceptible to Johne’s disease?
Calves under 6 months - become more resistant when they get older
But dont show clinical signs of infection until they are 2-5 years old - long incubation period
What are the clinical signs of Johne’s disease? What is the first sign?
Drop in milk yield - early sign
Profuse watery diarrhoea
Gluteal muscle wastage
But still bright cow with no anorexia
What is the pathogen that causes Johne’s disease?
Mycobacterium avium paratuberculosis
How is Johne’s disease transmitted?
Faecal-oral
Transplacental
Semen
Milk
How long does Johne’s disease survive in the environment?
Over 1 year in temperate conditions
But usually about 6 months
How do you diagnose Johne’s disease?
ELISA - most widely used
Faecal smear - Zeil-Neilson stain, pink acid fast bacteria
History/clinical signs
PCR
What does Johne’s disease look like on faecal smear?
Bright orange/pink mycobacterium
Appear in clumps inside macrophages - pathognomic
Can be difficult to find
What does the intestinal mucosa look like from Johne’s disease?
Corrugated - cant pull flat, not stretchy
Yellow if wash it - from toxin
What are the drawbacks of using ELISA to detect Johne’s disease?
Very high specificity by low sensitivity
Misses a lot of cases but if you find it then it definitely has it
So only works if you use it regularly
What are the drawbacks of using PCR to detect Johne’s disease?
Very sensitive but seems to miss lots of cases in the field
What vaccine is used for Johne’s disease and what are its drawbacks?
Live attenuated vaccine
Affects TB tests as induces sensitivity to other mycobacteria
Is it a zoonosis?
Not sure - present in milk and meat
Not always killed in pasteurisation
Seen in some Crohns disease cases in humans
How is Johne’s disease controlled/prevented?
Cull infected cattle
Segregation
Feed calves colostrum from uninfected cows
Dont pool colostrum
Dont let calves in pastures with adult faeces on
What is malignant catarrhal fever? What signs does it cause?
Fatal disease of cattle
Causes oculo-nasal mucopurulent discharge, corneal opacity, mouth ulceration, lymphadenopathy, pyrexia, dermatitis
How is malignant catarrhal fever spread?
Associated with sheep
No cattle-to-cattle spread - cows are dead end hosts (so doesnt cause epidemics)
How do you diagnose malignant catarrhal fever? What is the treatment for it?
Diagnose on clinical signs
No treatment - euthanase
What is bovine papular stomatitis?
Pox virus of little clinical significance
Causes round red papules on muzzle nostril and buccal mucosa
Heals quickly, good immunity
How can you tell a cow has bovine papular stomatitis rather than a more serious disease?
Lesions are NOT on the tongue
Only on muzzle, nostrils and buccal mucosa
What respiratory disease is a differential diagnosis for malignant catarrhal fever?
Infectious bovine rhinotracheitis
What is winter dysentery? What is it caused by?
Highly contagious disease causing explosive profuse dark diarrhoea
Around housing time - Nov
Caused by coronavirus
What is the prognosis of winter dysentery?
Very good - recover in 5-7 days, good immunity
Does cause milk drop, dehydration, decreased rumen motility though
What disease can winter dysentery look like an outbreak of?
Salmonella
How do you diagnose winter dysentery?
Epidemic of diarrhoea just after housing - suggestive
No pyrexia
No specific pathogens found in faeces
What deficiency can cause diarrhoea?
Copper deficiency
What are some infectious causes of saliva loss in cattle?
Malignant catarrhal fever
Foot and mouth
Wooden tongue
Vesicular stomatitis
Calf diphtheria
Abscess/lesion in the mouth
What physical causes of saliva loss are there in cattle?
Oral/oesophageal/pharyngeal foreign body - choke
Teeth problems
Jaw fracture
Facial nerve paralysis
What toxic causes of saliva loss are there?
Rhododendron toxicity
Botulism
Buttercups
What causes wooden tongue?
Actinobacillus lignieresii
Rough forage causing lesion on tongue, swelling and fibrosis
How do you treat choke in cows?
Gag
Manipulate, stomach tube
May need muscle relaxant
What is actinomycosis?
Lumpy jaw - actinomyces bovis gets into bone of jaw and causes hard painless swelling, affects teeth
How do you treat actinomycosis?
Treat with tetracyclines
Treat early for good prognosis
What is pasture bloat?
Gas of fermentation trapped in foam due to eating lots of legumes (clover)/lush pasture
Causes rumen distention and death
What types of cows are at more of a risk of pasture bloat?
Jerseys
Young cattle
Good condition animals
How do you treat pasture bloat?
Anti-foaming agents - birp
Oils, detergents
Give by stomach tube
NOT a trocar - gas in foam wont release
What is grain bloat?
Feeding lots of rapidly fermentable carbohydrate eg. finely milled cereals
Causes ruminal acidosis
What are the clinical signs of grain bloat?
Bloat
Anorexia
Dehydration
Collapse
Severe metabolic acidosis - tachypnoea
Diarrhoea - very acidic, wear a glove
Death
What is the treatment for grain bloat?
Rumenotomy - scoop out contents
Correct acidosis and dehydration
Feed forage
Rumen function stimulants
What causes free gas bloat?
Oesophageal obstruction
Pressure on oesophagus
Smooth muscle function issues
Where do you usually see bloat in the abdomen?
Left sub-lumbar fossa
How do you treat free gas bloat?
Stomach tube
Trocar and cannula - needle into rumen, then spike and tube pushed in
Treat cause eg. remove FB
What is the most common cause chronic ruminal distention?
Poor weaning management of artificially reared calves
Issue with rumen motility - nerves, diet
What conditions cause chronic ruminal distension as a consequence?
Vagal indigestion - damage to vagal nerve
Sand impaction
Alimentary tract carcinoma
Ru
What is the treatment for chronic ruminal distension?
Indwelling trocar and cannula (red devil)
Diet change
Sometimes none
What is traumatic reticulitis?
Foreign body ingestion - usually wire poking/penetration of the reticulum wall
What are the general symptoms of traumatic reticulitis?
Dull, anorexic
Agalactia
Fever
Abdominal pain
Grunt
What are the pathogenic processes that traumatic reticulitis can cause?
Reticular abscessation
Localised peritonitis
Traumatic pericarditis
Liver abscess
Peritonitis
How can you test for abdominal pain in cows?
Withers test - pinch withers, when they drop their back they stretch their abdomen and will grunt
How do you treat traumatic reticulitis?
Rumenotomy and removal of foreign body
Maybe magnets for prevention
What are the diseases of the abomasum?
Left displaced/right displaced abomasum
What cows tend to get displaced abomasum?
Post partum dairy cows within 6 weeks of calving
Fat cows
Ketotic cows
Cows with low dry matter intake
Which side of displaced abomasum is severe and life threatening, can progress to total abomasal outflow obstruction from torsion?
Right sided abomasum
Left side is not as severe
What are the clinical signs of left displaced abomasum?
Reduced milk yield
Reduced appetite
Abnormal sounding viscous on left side on auscultation
What are the clinical signs of right displaced abomasum?
Severe dehydration
Ketosis, hypochloraemic, hypokalaemic
Metabolic alkalosis
Shock
Death
What are some intercurrent diseases that predispose to displaced abomasum?
Ketosis
Excessive fat mobilisation
Hypocalcaemia
Retained foetal membranes
Acidosis, anorexia, low DMI
How do you prevent displaced abomasum?
Dry of cows at optimum BCS - 2.5-3
Maintain BCS until calving
Monitor for rumen fill and acidosis signs
Monitor for ketosis
Treat any hypocalcaemia
What can cause small intestinal obstruction in cows?
Intussusception
Gut tie - castrating calves by pulling, vas deferen snaps, goes back up and wraps itself around intestines
What are 4 endemic pathogens causing calf diarrhoea?
Rotavirus
Coronavirus
Crypto
Enterotoxigenic E. coli
What pathogen is likely to be causing the diarrhoea if the calf is between 0 and 6 days old?
Enterotoxigenic E. coli
What pathogen is likely to be causing the diarrhoea if the calf is between 6 and 21 days old?
Rota
Corona
Crypto
What pathogen is likely to be causing the diarrhoea if the calf is over 21 days old?
Coccidiosis
How does rotavirus cause diarrhoea?
Destruction of microvilli in enterocytes
What does the diarrhoea from rotavirus look like?
Thin, yellow white diarrhoea
How does coronavirus/winter dysentery affect calves?
Commonly subclinical
Diarrhoea - can be acute and severe causing rapid death
Chronic debilitating diarrhoea in older calves
How does coronavirus cause diarrhoea in calves?
Malabsorption from villus stunting and loss of intestinal epithelium
Very bad if combined with rotavirus
When do calves get cryptosporidia? When do they gain immunity?
5-7 days
Reach age immunity at 3 weeks
What does cryptosporidia cause in calves?
Profuse watery diarrhoea for about 7 days
How do you treat cryptosporidia?
Poor response to treatment
Better to do preventative
What type of E. coli is a zoonosis?
Verotoxigenic E. coli
How is milk processed in calves?
Milk bypasses the rumen via oesophageal groove
Acid causes paracasein to clot quickly in abomasum
What factors contribute to nutritional diarrhoea?
Milk mixed to inappropriate concentrations or temperatures
Irregular feeding intervals
Poor quality milk product
Overfeeding
What causes nutritional diarrhoea?
Unstable clot formed - casein spills over into the SI
results in poor digestion and poor growth rates
What causes calf diphtheria?
Physical abrasion eg. from feeding fibrous material
Allows opportunist fusobacterium necrophorum infection
Necrotic infection of oral cavity/larynx
How do you treat calf diphtheria?
Penicillin
What is ruminal bloat in calves?
When milk spills into the rumen due to failure of oesophageal groove formation
Milk ferments causing bloat, colic and pasty scours
How do you treat ruminal bloat?
Stomach tubing
Surfactant - for foam
What is immature rumen syndrome?
When calves eat large volumes of fibre and the immature rumen cant digest it adequately
The rumen dilates but the calf is still hungry
What are the clinical signs of immature rumen syndrome?
Pot bellied appearance
Thin pasty faeces
How do you treat immature rumen syndrome?
Drastic reduction in roughage
Use shavings as bedding
Palatable concentrates
Give adult rumen fluids to calf by inoculation
What do you assess for in calf scour cases?
Demeanour - presence of suck reflex
Hydration status
Condition score
TPR
How does dehydration from scours cause death in calves?
Loss of water and electrolytes causes metabolic acidosis
Hyperventilation to correct acidosis causes loss of potassium and sodium
Hyperkalaemia causes cardiac arrest
What age of calf is more likely to have a severe acidosis?
Over 6 days old
What factors increases calf susceptibility to scours?
Inadequate colostrum
Environmental stress
Nutritional errors
Concurrent disease
What are the features of metabolic acidosis?
Hyperpnoea
Brradycardia
Cardiac arrhythmia
Increased lactate/lactic acid
Decrease then increase in plasma K+
What contents should be in rehydration fluids?
Na+
Cl-
Glucose
How do you give IV fluids to a calf?
Small cut over vein
Put in catheter pointing down
Give hartmanns or sterile saline with carbonate to correct acidosis
bandage in
How much fluid should you give IV to a calf?
5-10 litres over 24 hours
How do you choose an oral fluid t ogive a dehydrated calf?
Rehydration ability
Ability to correct acidosis
Nutritional ability
When should you introduce milk to a dehydrated calf?
As soon as the suck reflex is present
What are the benefits of giving milk to a dehydrated calf?
Feed the calf
Reed the gut mucosa
Ensure get Ca, Mg, vitamins etc.
Improves renal function
When should you give antibiotics to a scouring calf?
if has E. coli or salmonella
or if didnt have enough colostrum
How can you prevent calves getting diarrhoea?
Adequate colostrum - feed and then feed diluted with milk for first 7-10 days
Immunise dams against rota and coronavirus
Improve hygiene
How much colostrum should calves recieve?
10% of bodyweight within 6 hrs of birth
What is used to prevent diarrhoea caused by crypto?
Halocur
