Enteric disease in weaned pigs Flashcards
(22 cards)
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
16
Q
Swine dysentery pathogenesis
A
oral infection –> colonises in LI mucosa –> multiplies in crypts –> invades goblet cells and epithelial cells
–> haemolysin produced and cell loss occurs from inter crypt areas –> inflammatory response of mucosa results in loss of tissue and bloos and loss of colonic resorption of Cl and Na ions
17
Q
Swine dysentery:
- CS (5)
- Pathology (4)
A
- incubation: 6-14 days
- thin animals
- fresh blood and mucus in diarrhoea
- afebrile
- recover after 2-3 weeks
Pathology:
- dehydrated carcase and in a poor condition
- LI flaccid, thin walled and may show serosal evidence of inflammation
- contents: fluid with blood and mucus
- mucosa thick with surface blood, necrotic debris and mucus
18
Q
Swine dysentery
- Dx (5)
- Tx (4)
A
Dx:
- diarrhoea containing blood and mucus in weaned pigs
- loss of condition, slow recovery, some deaths (25 %)
- LI affected: inflamed mucosa with blood mucus and necrotic debris
- PCR testing of faeces/intestinal contents
- Isolate B. hyodysenteriae to confirm
Tx;
- tiamulin, valnemulin, aivlosin, lincomysin
- parenternal the severely affected pigs
- teat all pif sin drainage contact
- disinfect after treatmenT
19
Q
Swine dysentery
- control (4)
- elimination
A
Control:
- continue medication at a low level for 4 weeks after treatment
- lsats and solid partitions reduce spread
- treat batches into clean accomodation
- Isolation prevents entry
Elimination:
- full depopulation/repopulation may be required
20
Q
Spirochetal Diarrhoea
- Facts (6)
- Dx (4)
- Tx
A
- like swine dysentery but no deaths
- growth suppression is common
- 6-8 weeks onwards
- disease lasts 10 days-3 weeks
- spontaneous recovery
- cause by brachyspira pilosicoli
Dx:
- LI lesions only
- mucus and reddening but blood is rare
- spirochaetal invasion of colonic mucosa forms a false brush border
- specific monoclonal antibody and PCR
-Tx: as swine dysentery by also tylosin
21
Q
Colitis (4)
A
- diarrhoea with loss of condition
- from 6-8 weeks onwards
- continues for several days
- no mortality
22
Q
Gastric Ulceration
- Causes (2)
- CS (4)
- pathology (5)
- Tx
A
- growers and finishers on finely ground rations & high levels of wheat in diet
- 60% of slaughter pigs
CS:
- pale and sometimes abdominal pain
- sometimes malaena
- subnormal tmeperature
- often found dead
Pathology:
- pale carcase
- ± blackened faeces
- ulceration pars oesophagea
- blood clot in stomach
- altered blood in gut, mucosa normal
Tx:
- none- prevention by elimination
