Multiple Tools for IP Control Dan Morrical Iowa State University 515-294-0847
[email protected]
Old way Drugs, drugs, drugs Newer, stronger, bigger doses No longer sustainable No new drugs
Tools available Knowledge Genetics Selective treatment Parasite resistance Rotational grazing Parasite resistance Land resource
Knowledge High risk animals High risk times Dry lot versus pasture Stock density
Knowledge Larvae levels
Typical parasitic lifestyle Eggs: Development from egg to infective (L3) larvae can occur as early as 6 days Molt into L1’s in the egg then hatch Nematodirus develop into L3’s in the egg, then hatch Most ova do not survive very cold ambient temperatures
Typical parasitic lifestyle L3’s - infective stage Thick cuticle protects them from drying Cannot feed - finite life span Warm temperatures increase their metabolic rate.
Can survive some freezing
Haemonchus Adults live in abomasum ingest 0.05ml blood/worm/day 5000 worms will remove 250 ml of blood.
Adults are very prolific egg layers Haemonchus L3’s are not as cold hardy as others Most L3’s live for 1-3 months
Genetics Katahdin and NSIP Dorpers ?, Boer goats ? Genetic resistance vs production
Selective treatment FAMACHA treat pale eyes Labor Faith
Resistance Our parasites truly resistant Fecal egg reduction test Drenchrite Refusia
Grazing management Better forage production Better health status Enough nutrients to feed sheep and parasites.
Land Resource Pasture A
Pasture B
Hayed in 07
grazed in 07
Grazed in 08
hayed in 08
Land Resource, option b Pasture A
Pasture B
Cattle in 07
Sheep in 07
Sheep in 08
Cattle in 08
Land Resource, option b Pasture A
Pasture B
Pasture C
Cattle in 07
Sheep in 07
Hayed 07
Hayed in 08
Cattle in 08
Sheep 08
Sheep in 09
Hayed in 09
Cattle 09
Safe pastures No sheep or goats from either July 1 to December 31 or January 1 to June 30
Alternative approaches
Cat thyme Sericea Lespedeza Copper wire bolus Fungus DE
Research Design Ewes: 0, .5, 1 and 2 g Lambs: 0, .5, .75, 1.0 g
Results FEC Ewes: Day 7 FEC increased in ewes to >2000 epg for 0 and .5 gram dose FEC decreased in ewes to 1500epg on day 35
Results PCV Ewes: from day 0 to day 21 all groups went down slightly 4 ewes had to be treated with PCV below 18 None were in the 2 gram group
Results AST Lambs: no indication of copper problems Ewes: no indication of copper problems Base diet is pasture and TM salt
Applications Extreme care 2 gram dose is like feeding 25 PPM copper for 50 days Documented resistance
Use serum AST with 2 g COWP in 5 ewes or less as first step
Summary Drugs
(anthelminics) are not the solution Develop whole farm strategy Be creative Work with your Veterinarian
Questions