The effect of plane of nutrition on the growth and development of the East African dwarf goat. I. Effect of plane of nutrition on the live-weight gains and the external measurements of kids

Abstract

1. Fifty-five kids of the East African dwarf goat were used in the experiment. The kidding percentage was 107·8%, and the twinning percentage 12·7%; the proportion of twin births increased in the latter stages of the experiment, related to the longer period the late-kidding dams had spent on the rising plane of nutrition.2. The percentage of female kids to total kids born was 56·4%, male kids 43·6%. The mean birth weight of female kids was 4·5 lb., compared to 5·2 lb. for male kids.3. The sex difference in live-weight increase increased markedly after 16 weeks of age. The growth of females slowed down to approximately ½ lb. per head per week, whereas that of males continued to increase at the rate of approximately 1 lb. per head per week. H-plane female kids reached 33 lb. at 31 weeks, H-plane males achieved the same weight at 20 weeks of age.4. The effect of plane of nutrition on the live weights of experimental kids of both sexes was statistically significant as from the third week of age. H-plane kids reached 33 lb. live weight at approximately 26 weeks of age, L-plane kids at about 48 weeks.5. The kids initially placed on a L-plane of nutrition exhibited a marked resilience when switched to the H-plane. The live-weight gains after switching were for females as great as, and for males greater than, the gains made by kids on a H-plane of nutrition throughout the growing period.This recuperative capacity of animals changed from L to H levels of diet, at or before the point of inflexion of the growth curve, has now been clearly established for all types of farm livestock examined, the pig, the sheep, the chicken and the goat. Both sexes exhibited this capacity to recover from initial low-plane feeding.