♫ Bad Bugs, Bad Bugs, Whatcha Gonna Do? ♪ : Parasites in Sheep

1. ♫ Bad Bugs, Bad Bugs, WhatchaGonna Do? ♪ : Parasites in Sheep Dr Chris Clark WCVM University of Saskatchewan

3. Sheep Parasites • The price of doing business! • PGE • Coccidiosis • Tapeworms • Fluke • Skin parasites

5. There’s a problem • When we think of parasites we think of drugs • Minimal drugs licensed for parasites for sheep in Canada

6. What does this mean for a sheep producer? • Drugs used in food animals are federally regulated • Only a veterinarian can prescribe extra-label drug use

7. Its more complicated • Drugs • Identified by DIN number on packaging • Extra-label use permitted with veterinary prescription and withdrawal period • Pesticides • Identified by PCP number on package • No extra-label drug use permited

8. Antibiotic labels tell you all you need to know SC = under the skin IM = in the muscle IV = in the vein

9. Implications • Treatment options for sheep are limited • You need a veterinarian to prescribe parasite treatments • Use gFARAD for withdrawal information

10. The Canadian Prairies • Good for sheep • Bad for most parasites • “its’s a dry cold” • It is not bad luck it is bad management

11. Coccidiosis • Mainly a problem of intensively raised lambs • Especially indoors • Outdoors needs specific conditions

12. Onset early as 8d • Typically 4-6 weeks • Severe diarrhea +/- blood • Tenesmus • Morbidity high, mortality low

13. Coccidiosis • Etiology • E. cradallis, E. ovinoidalis • Diagnosis • Epidemiology, fecal, PM • Not all that easy!

14. Management • Avoid the epidemiology • Use of coccidiostats • Deccox • Baycox • Monensin • Amprolium • problems • Treatment • TMS

15. Parasitic gastro-enteritis (PGE) • Means different things in different regions • Teladosagia (ostertagia) • Haemonchus • Nematodirus • Trichostrongylus

16. Trichostrongyloidea Eggs passed in feces Hatch and develop to L3 on pasture L3 ingested Develop to L5 – adult in host causing disease Pass eggs in feces Hypobiosis Small ruminants – Periparturient egg rise is significant Adults develop some immunity

17. Canadian Prairies • Egg –L3 development • Requires heat and humidity

18. Haemonchosis • Barbers pole worm • Found in abomasum • Blood sucker • Prolific • Results • Ill thrift • Anemia, bottle jaw • Sudden death

19. Epidemiology • Eggs passed in feces must develop to L3 on pasture • 5 day minimum • Requirements • Heat 18-26C (< 5 dormant, <10 nothing) • Humidity 100% • Canadian prairies –lucky to get one cycle

20. Significance • Most years disease is rare • If the weather is right you have a problem

21. Haemonchus diagnosis • Reality • PM • Clinical signs • High egg count

22. Haemonchus control • Traditionally • Deworm • Deworm • Deworm • Repeat as required

23. Teladosagia • Nematode of the abomasum • Larval forms disrupt acid production • Type 1 disease • Diarrhea and weight loss • Type 2 disease • Early spring – bottle jaw

24. Natural cycle in ideal conditions

25. Traditional control Deworm ewes at lambing Deworm lambs repeatedly throughout late summer and fall

26. Nematodirus • Intestinal worm • Egg development in 2-3 months • N. battus– different epidemiology • Diagnosis difficult as disease is prepatent • Egg looks like liver fluke

27. Trichostrongylus Intestinal worm with epidemiology and effects similar to Teladosagia Eggs are indistinguishable

28. Controlling PGE • Understanding the epidemiology • All research is done in a different climate • Periparturient egg rise • Egg – L3 development on pasture • Cycling in lambs • Some winter die off

29. Using epidemiology to control PGE • Periparturient egg rise • Can last 8 weeks • Deworming ewes in association with parturition • Can be used to minimize pasture contamination in late spring

30. Using epidemiology to control PGE • Deworm lambs at weaning and move to new pasture/feedlot

31. Anthelmintics BZ- Benzimidazoles LM – Levamisol, Pyrantel, Morantel AV- Avermectins

32. Anthelmintic resistance • Do you have a problem? • Fecal egg count reduction test • FEC • Weigh and dose • Wait 10d then redo FEC • Should be >85% reduction in egg count

33. Anthelmintic resistance • Biosecurity • Dose all new arrivals on arrival • Weigh and dose • Dose on an empty stomach • Wait 2-3 days before turn out

34. Anthelmintic resistance • Weigh and dose • Avoid rotation of dewormer classes • Dose when needed (egg counts, FAMACHA, BCS) • Refugia • Dose and move

36. Tapeworms Intestinal Cystic Disease

37. Intestinal tapeworms • Monezia • Not important

38. Intermediate hosts

39. Taeniaovis Dog - sheep

40. The costs of disease 2009 – 270 lambs in the 1st 6 months ”In heavy infestations the carcass is condemned. It is commonly considered that an animal is heavily infested if lesions are discovered in two of the usual inspection sites including the masseter muscle, tongue, oesophagus, heart, diaphragm or exposed musculature and in two sites during incision into the shoulder and the rounds. Carcasses with C. ovis infestations may not be acceptable for export.”

42. Traditional control • Typified by Australia and New Zealand • Routine deworming • Mandated with appropriate products • Feed control • Freezing • Cooking

43. Liver fluke • Complex life cycle • Absolute requirement for snail • Lymnaeatruncatula

44. Liver fluke - disease • Acute • Sudden death at pasture • Sub acute • Poor doing fall/winter • Chronic • Anemia, hypoproteinemia poor BCS

45. Fascioloides Magna Sheep is an aberrant host • Continual fluke migration • Presentation • Death • Control • Avoidance f snail areas • Triclabendazole

46. Liver Fluke Control • Albendazole • Adult fluke only • Triclabendazole • V effective • Not in Canada

47. Skin parasites • Lice • Keds/ticks • Mites • Flies

48. Lice • Bovicolaovis– chewing • Linognathus spp. -sucking

49. Keds • Melophagusovinus

50. Ticks Ticks latch on and feed Have 8 legs Do not live on the goat