Resistance To H. Contortus Infection In Goats On Artificial Infection: Preliminary Findings.

Abstract

Natural infection with Haemonchus contortus was monitored in 300 kids using worm egg counts per gram (EPG) from the age of 2 months to one year. Some kids had low counts 201 ñ 118.2 while others had high count 601.9 ñ 199.9 EGP. Eleven goats from thelow counts group A and nineteen from the low count group B were cleared of worm infestation using Invermectin under complement. The two groups were then artificially infected with 500 larvae per kid from same (H. contortus) isolate. Individual goats within the groups had low EPG throughout the study indicating resistance to the challenge. Goats in group A had significantly lower EPG (725 ñ 212.5) than group B (1643.2 ñ 463.4) P(t=1.80.05) throughout the period. This could reflect a few group B goats with very high EPG rather than general difference between the groups. The indication by individual goats of greater resistance to (H. cortortus) than others provided an important direction for future research.