Effects of protein supplementation on Haemonchus contortus infection in goats
Z. Wang, S. P. Hart, A. L. Goetsch, R. C. Merkel, L. J. Dawson, and T. SahluProceedings of the 9th International Conference on Goats. Page 268. International Goat Association. 2008
Protein supplementation may enhance host immunity to parasites. However, the mechanisms by which supplemented protein augments immunity are not clear. The study reported here determined effects of varied protein intake on immune responses in goats infected with Haemonchus contortus. Thirty-six Boer x Spanish goats (3 yr, 46 ± 5.9 kg BW) were dewormed and allocated to six groups of six animals each, housed in group-pens, and fed individually with a Calan gate feeding system. The treatment arrangement was a 2 x 3 factorial. Goats were fed hay-based iso-caloric (ME = 8.0 MJ/kg DM) diets containing 0, 5%, or 10% fish meal (FM). The dietary CP was 6.6%, 9.5%, or 12.4%, respectively. Thirty days after being fed the diets, goats allocated to infected groups were administered with 10,000 H. contortus infective larvae per animal, and all animals remained on the experimental diets for 4 additional weeks. We found that worm eggs appeared in feces from the goats fed diets with 0 or 5% FM in week 3 but were not detectable in goats fed the 10% FM diet until week 4 post-infection. The infection of H. contortus induced increases (P < 0.01) in blood eosinophil and tissue mast cells. The numbers of mast cells in spleen and mesenteric lymph nodes from the infected goats were lower (P < 0.05) in animals fed the 10% FM diet. The number of eosinophils was not affected (P > 0.05) by protein supplementation. Serum concentration of IgA increased (P < 0.01) after infection but was not affected by dietary protein. Serum IgG in infected goats increased (P < 0.05) with dietary protein 7 days post infection but declined thereafter. Worm burden was not affected by dietary protein. The results suggest that protein supplementation in goats transiently inhibits worm fecundity through enhanced IgG expression.
Extension Activities | Research Activities | Other Activities
Library Activities | Quiz | Search | About Us | Contact Us | Faculty & Staff
Research Extension Home | Top of Page
Copyright© 2000 Langston University Agricultural Research and Extension Programs
P.O. Box 730 Langston, OK 73050 Phone 405.466.3836