GIT Flashcards
Algorithmic approach to aetiologies of abdominal signs in small ruminants
Worm egg counts
Faecal exam is
vital
:
o
WEC (remember need spec
ial techniques for fluke eggs)
—
consider situations were
you’d do several individual animals vs. a representative ‘bulk’ sample from the mob
‘Bulk’ WECs commonly done to
monitor a
mob
of sheep: collect 10
-
20 fresh
samples
(i.e., 1
-
2 faecal collection trays) directly
from paddock or yard
s
→
quick, easy, cheap ($20
–
25/tray)
o
Faecal
culture
(need to collect directly from rectum) can also be used, but need good
interpretation
of results:
consider w
hat is easy to culture/may be an incidental
finding vs. what is hard to cultu
re and may give false negatives
What is redgut?
Redgut
Redgut with intestinal rotation or ventral displacement of the intestines
Causes of sudden death in sheep
Epi and Pathogenesis of Red Gut
Clinical signs and necropsy findings in Red Gut
Treatment and control of Red Gut
Intermittent inappetance, dullness, recumbency and deaths in late pregnant ewes– receiving on and off grain ration in paddock
Mgt and prevention of ruminal acidosis?
History and risk factors of ruminal acidosis
Clinical signs and diagnosis of ruminal acidosis
Treatment and prevention of ruminal acidosis
Epi and risk factors, and clinical signs and diagnosis of shy feeders?
Management of shy feeders?
What is a key time to watch out for ruminal acidosis in sheep in intensive systems?
DDX for sudden death in sheep aside from ruminal acidosis
Shy feeders management and prevention
General guidelines for introducing animals into feedlots
May see a number of different disorders in the same mob if under stress
Enterotoxaemia/pulpy kidney in a 3-week-old goat kid: OK at 6 am, by 8 am vocalising,
recumbent, swollen abdomen. Treated with
finadyne
. Dead at 8:30am
Worm– treatment and control?
Persistent inappetance, Salmonellosis and inanitition syndrome (PSI) Epi and general
Enterotoxaemia Pathogenesis, Epi, and Diagnosis
Enterotoxaemia treatment and control?
Coccidiosis Epi, Clin signs, and diagnosis?
Treatment and control of coccidiosis?
Yersiniosis epi, clin signs, diagnosis and tx?
Production areas of sheep in AUS
Costs to the industry from parasites in sheep
Nematode life cycle main points
Summar (jan- mar)
Epi in south-eastern Australia (winter rainfall)
Patterns of infection- winter rainfall?
Summer autumn contamination
Worm egg counts of wethers in a dry summer
Worm egg counts of wethers in a wet summer
Patterns of infection summer rainfall
Current control programs (winter rainfall)
- Test for drench resistance (every 3-4 years): WECRT or single post-drench WEC
- 1- or 2-strategic summer treatments: must be highly effective (combinations), variable timing of SD1- pastures drying off/ Dec, SD2 in Feb
- WEC Monitoring to avoid unnecessary treatments: bulk WEC, 10-20 sheep/mob, all mobs before SD2 (cut off is 25-50 epg), before SD1, weaners- after autumn break (every 4-6 weeks), ewes before lambing (need a pre-lamb drench?)
- Treatment of introduced sheep
- Grazing management (wet years, high rainfall): lower risk pastures for weaners (& maiden ewes)
- Nutrition: meet feed availability & CS targets for ewes, growth targets for weaners, feed protected protein, pastures containing condensed tannins
- Breeding for increased immunity (resistance)– rams selected for low WEC (-ve WEC EBVs)
- Identify risks for low refugia: drought and crops, strongly mediterranean climates
Anthelmintic resistance
Efficacy of the macrocyclic lactones
Risk factors for resistance
Anthelmintic resistance issues
Has Anthelmintic rx reduced farm productivity and profitability?
Options to combat low refugia populations
But… caution needed:
- Worm ecology and control programs differ markedly between regions: amount and distribution of rainfall, length of growing season
- Importance of summer/autumn contamination in winter rainfall areas
- Differences between wool and prime lamb flocks
Estimates
of over
-summering
larval
populations in Victoria
Conclusions on refugia- SE Australia
preparing low risk pastures
Sheep-cattle interchange
Effects of age and lactation on total worm counts
Effect of reproduction and genotype on total worm count
selection for low WEC- yearly gains accumulate to give long term control
Host immunity– vaccines to nematodes?
Nematophagous fungi
Liver fluke epi
Liver fluke control options
Goat considerations with parasites
Take home points sheep parasites
Patterns of infection- winter rainfall
nutritional strategies– parasites
Resistant ewes have a lower peri-parturient rise in WEC
The major problems causing diarrhoea in small ruminants
- Adult sheep
- Yersiniosis
- Salmonellosis
- (OJD) - Nutritional scouring- lush feed, PRG endophyte, phalaris
- Neonatal scouring:
- Cryptosporidia, Giardia
- E. coli, Rota, and Coronaviruses
Pathophysiology of diarrhoea
Hypersensitivity scouring– winter and uniform rainfall areas
Does treatment with a controlled release anthelmintic capsule prevent most dag??
Low doses of worm larvae induce scouring in susceptible sheep
What happens in the gut of hypersensitivity scouring sheep?
Cause and diagnosis of hypersensitivity scouring
Control of hypersensitivity scouring
Weaner enteritis/ colitis
DDX for weaner enteritis/ colitis
Diagnosis
Weaner enteritis treatment
Yersiniosis and risk factors
Diagnosis of Yersiniosis
Yersiniosis treatment
Salmonellosis
Treatment and control of Salmonellosis
Nutritional scours
Neonatal diarrhoea
Relative Risk and Odd Ratio
