The effect of dietary protein on the productivity of West African Dwarf (WAD) goats infected with Haemonchus contortus.

The effects of increased dietary protein on the performance of West African Dwarf (WAD) goats infected with Haemonchus contortus were investigated. 28 pubertal 9-12-month-old female goats were divided into two equal groups A and B and fed on high and low protein diets, respectively, from day 1 of pregnancy (day of mating) to 6 weeks post-partum. Each animal was trickle infected with a total of 2400 infective larvae of H. contortus over 4 weeks starting from day 1 of pregnancy and the prepatent period recorded. Live weights and body condition scores were measured weekly and the changes determined by subtracting the initial value from each of the subsequent values. Birth and weaning weights of kids as well as stillbirths and foetal loses were also determined. High protein diet improved the ability of goats to resist worm establishment and patency, which was manifested as significant increase in the prepatent period in group A than in the low protein diet group B (p<0.001). Also high protein diet resulted in significantly higher increase in body weight during pregnancy (p<0.01). During lactation both groups rapidly lost weight although body weight increase relative to preinfection value remained significantly higher in group A than B (p=0.05). Between weeks 3 and 13 post infection, the body condition scores increased but were significantly higher in group A than in group B (p<0.001). From weeks 16 to 27, the body condition scores remained significantly higher in group B than group A although both experienced severe losses during lactation. Group A delivered significantly heavier kids than group B (p<0.001) and had no foetal losses as occurred in the latter. However, the level of supplementation had no influence on weaning weights as there was no significant difference in the weaning weights of kids of both group (p>0.05). It is concluded that lactation demand for dietary protein is higher than that for gestation since both body weights and body condition scores deteriorated in both group during lactation, and that improved dietary protein enhances resistance to parasite establishment (increased prepatent period) and resilience in terms of kidding performance, birth weight and survival of neonates.