ANSC 485 Lecture Notes - Lecture 14: Livestock Grazing Comparison, Anthelmintic, Electronic Program Guide
Document Summary
20% of the horses carry 80% of the parasites. Loss of appetite: weight loss, decreased stamina, depression, dull and rough hair coat, tail rubbing or hair loss, coughing, colic, diarrhea. Eggs are deposited on pasture in manure. Peak fecal egg production: september - april. Lowest fecal egg production: may - august. Why: development: 45 80f, persistence: <45f, destruction: >85f. Lower levels of eggs on pastures november through march. Infection levels can be reduced by stabling during coldest months. Larvae burrow into the wall of the large intestine, producing irritation. Erupt at once in fall or after deworming. Results in diarrhea, poor growth, reduced performance. Common names red worms or blood worms. Larvae penetrate intestinal lining and migrate to cranial mesentery artery. Mature worms return to large intestine and lay eggs. Easily controlled with dewormers and eliminated from most farms. Young horses less than 2 years of age.
