Enteric disease in weaned pigs Flashcards
1
Q
E.coli
- facts (4)
- pathogenesis
- outcomes (3)
A
- ETEC
- 1-3 days post weaning
- watery diarrhoea often grey/brown
- obvious dehydration
- bacteria adhere to brush borders by fimbriae –> produce LT enterotoxin –> diarhhoea by effect on ion transport mechanism (fluid follows Cl and Na ions into the lumen of the gut)
outcomes:
- die of dehydration 2-5 days
- recover with some reduction in growth rate
- remain stunted
2
Q
E.coli
- CS (3)
- pathology (8)
A
CS:
- watery-brown diarrhoea 1-5 days post weaning
- dehydration
- rough hair coat
pathology:
- dehydrated carcase
- tacky muscles/fascia
- perineal diarrhoea/scalding
- intestine only organ affecter
- dark liver
- mesenteric LN enlargement
- SI & LI dilated with fluid contents
- wall and villi are normal
3
Q
E.coli
- epidemiology (3)
- Dx (5)
A
epidemiology:
- FO transmission
- persists in sheds –> successive litters affected
- predisposed by draughty conditions, poorly digestible food, high protein diets and poor hygiene
Dx:
- timing (1-5 days post weaning)
- afebrile
- CS
- PM changes restricted to SI
- ETEC in diarrhoea/SI contents
4
Q
E.coli
- Tx (4)
- Px (3)
A
Tx:
- medicated water (trimethoprim sulphonimide, amoxycillin, neomycinm apramycin, colistin)
- can medicate feed but less effective
- supportive
- improve hygeine
Px:
- zinc oxide for 14 days in feed (3.1kg/t)
- medicate drinking water 1 week post weaning
- medicate feed 2 weeks post weaning
5
Q
Oedema Disease
- facts (2)
- pathogenesis
A
- verocytogenic E.Coli
- 7-10 days after weaning or dietary change
organism proliferates in gut and then adheres to the brush border of the epithelial cells –> toxin spreads in blood stream –> toxin adheres to tissues throughout the body –> cell death and damage to the small capillaries in the gut
6
Q
Oedema Disease
-CS (9)
A
CS:
- NO DIARRHOEA
- ataxia
- squeaky voice
- head pressing
- blindness
- recumbency
- paddling
- coma
- paralysis
7
Q
Oedema Disease
- pathology (3)
- Dx (6)
A
pathology:
- oedema of forehead, large bowel, mesentery and greater curvature of stomach
- degeneration of media of arterioles
- increased perivascular spaces in brain
Dx:
- onset shortly after dietary change
- nervous signs
- CS
- NO FEVER
- oedema of carcase
- isolation of E.Coli
8
Q
Oedema Disease
- Tx (3)
- Px (6)
A
Tx:
- ABs in water
- treatment will not help those already affected –> manage symptomatically
- euthanise if not eating/drinking/standing within 3 days
Px:
- isolation
- avoid stress
- gradual dietary change
- solid rather than liquid feed
- reduce crude protein and increase crude fibre
- vaccine
9
Q
Proliferative Enteropathy
- facts (4)
- pathogenesis
- effects (3)
A
- Lawsonia intracellularis
- intracellular organism
- gram -ve rod
- shed in faeces, survives 2 weeks
oral infection –> invades epithelial cells of the SI via endocytic vacuole formation –> multiplies in cells, forming a micro colony, until the cell ruptures by apoptosis
- organism causes changes to cells such as hyperplasia of the glandular epithelium
- goblet cells disappear and epithelial cells elongate
- capillaries dilate and rupture at the apex of the villi
10
Q
Proliferative enteropathy
- CS (6)
- pathology (4)
- additional, specific pathology (3)
A
CS:
- weaning –> adult
- incubation for 3-6 weeks
- lasts 4-6 weeks
- pale pigs, poor growth, anaemic
- melaena/ grey cow pat faeces
- recover, die or remain stunted
Pathology:
- pale pigs in poor condition
- serosal surface of terminal ileum is pale and reticulated
- thickening and corrugation of ileal/caecal mucosa
- clots of blood in lumen if PHE
- in necrotic ileitis, the mucosal surface is necrotic
- in regional ileitis, the mucosa is eroded with muscular hypertrophy
- in haemorrhagic enteropathy, there is blood clot in the ileal lumen
11
Q
Proliferative enteropathy
- Dx (7)
- Tx (3)
- Px
A
Dx;
- pale pigs, at least 6 weeks old, hairy with malaena
- thickened terminal ileum or caecal mucosa
- polyps, necrosis, muscular hypertrophy or caecal mucosa
- proliferating mucosal crypts
- culture
- ELISA –> tells you when have seroconverted –> let pigs be exposed and seroconvert before medicating
- silver staining of tissues
Tx:
- tetracyclines paternally for seriously infected animals
- tetracyclines/ tiamulin in drinking water for 4-5 days
- tetracyclines/ tiamulin in feed for 1- casy-3 weeks
Px:
- tetracyclines for a course of treatment followed by a further course 18 days later
12
Q
Salmonellosis
- facts (4)
- epidemiology (4)
A
- Typhimurium, Derby, choleraesuis
- oral infection
- may cause bacteraemia and speticaemia
- parts of ears/tail can drop off due to micro thrombi in blood vessels, impeding blood flow
- choleraesuis is spread vertically and horizontally
- other salmonella enter by breeding stock, formites, feed and vectors
- all salmonellae are transmitted in faeces and resist drying
- carriage in tonsil and terminla ileum until death
13
Q
Salmonellosis
- CS (7)
- pathology (6)
A
CS:
- any age
- foul smelling diarrhoea
- necrotic tissue/blood
- fever to 41
- stunted growth with necrotic ear tips are common, deaths less common.
- rectal stricture syndrome can occur later
Pathology:
- good condition if septicaemia
- inflamed SI
- LI empt/fluid contents
- muscosa inflamed or necrotic
- peyer’s patches necrotic
- liver has pale, granulomatous areas
14
Q
Salmonellosis
- Dx (5)
- Tx (4)
A
Dx:
- CS (fever, wasting, diarrhoea with necrotic material and blood)
- ear tip necrosis, rectal stricture syndrome
- necrotic and catarrhal enteritits in SI
- isolation of salmonella
- meat juice ELISA (suspended???)
Tx:
- parenternal ABs
- water medication
- feed medication
- (amoxyclav, trimethoprim sulphonamide, neomycin, apramycin, fluroquinilones)
15
Q
Swine dysentery
Facts (7)
A
- mucohaemorrhagic enteritis
- spreads slowly from pen to pen
- brachyspira hyodysenteriae
- large spirochaete, beta haemolytic
- tyl A, B, C haemolysin genes sequenced
- sensitive to drying, acids and heating
- survives for weeks/months in organic matter
