Development of resistance to gastrointestinal nematodes in small East African goats

Development of resistance to gastrointestinal nematodes in two strains of Small East African (SEA) goats was studied in Morogoro. Sixteen Dodoma and twenty four Kigoma kids of both sex from a breeding programme were used. Kids were daily grazed on dominantly Haemonchus contortus contaminated pastures for eight months. Faecal and blood samples were taken once every month. Results showed that the sire, sex, type of birth and date of birth had significant effect on Faecal egg counts (FEC) in kids from four months of age and above (P<0.05). There was no significant difference in FEC, packed cell volume and blood eosinophils between strains (P>0.05). A marked level of resistance in kids of both strains was established at seven to eight months of age. Development of resistance was associated with peak eosinophilia and a dramatic fall in FEC. It is recommended that SEA goats should be selected for increased or decreased resistance to nematodes from seven months of age.