Data on reproductive performance of the White Fulani (Bunaji) cattle in Southern Nigeria were analysed. Age at first calving, first and overall calving intervals averaged 4.03 +/- 0.43 years, 436.19 +/- 9.32 and 420.98 +/- 4.11 days respectively. The year of birth significantly affected age at first calving and calving interval (P less than 0.01) but the season of birth had significant effect only on calving interval (P less than 0.05). In addition the age of the dam also affected the calving interval (P less than 0.05) but the sex of the calf nursed had no effect. Heritability estimates from half-sib analysis were 0.01 +/- 0.03, 0.26 +/- 0.10 and 0.28 +/- 0.08 respectively for age at first calving, first and overall calving intervals. Low repeatability estimates were obtained for calving intervals.

Records on 848 West African dwarf goat kids and 220 kiddings over a period of eight year's (1982-1989) were analyzed. The records were used to provide estimates of phenotypic and venetic correlations among parity, kidding interval, litter size at birth and body weight at various ages. Plenotypic correlation coefficients of +0.33 (P<0.01) and -0,17 (P<0.01) were obtained when parity was correlated with litter size at birth and kidding interval respectively. Phenotypic correlations among body weights were generally positive and significant (P<0.01). Parity was positively correlated (P<0.01) with body weight at the various ages except at 1 year (P>0.05). Litter size was, however, negatively correlated (P<0.01) with body weight at the various ages except at 1 year (P<0.05). The genetic correlations among body weights at variuus ages were positive and significant (P<0.01). Selection for body weight at in earlier age especially at 3 months is likely to result in improvement of yearling body weight.

No abstract

Records of 848 West African Dwarf goat kids and 220 kiddings over a period of eight years (1982-1989) were analysed. The records were used to provide heritability and repeatability estimates for litter size at birth, kidding interval (repeatability estimate alone) and body weight at birth, weaning, 3 months, 6 months, 9 months and 1 year of age. Heritability estimates of 0.28±0.005, 0.18±0.003, 0.14±0.003, 0.29±0.005, 0.11±0.003 and 0.17±0.004 were obtained for litter size at birth, body weight at birth, and at weaning, 3 months, 6 months, and 9 months of age respectively. Corresponding repeatability estimates were slightly higher than the heritability estimates. However, repeatability estimates of 0.04±0.030 was obtained for kidding interval.

Fifty two litters obtained over a period of 8 months (December 1986-July 1987) from the mating of eight bucks with twenty nine does (first mating) and twenty three does (second mating) all belonging to the New Zealand White breed of rabbits were used in this analysis. Mean gestation length, number of mating to conception, litter size at birth and parturition interval were 31.6 ± 0.2 days, 1.4 ± 0.1, 5.6 ± 0.3 pups and 79.0 ± 14.5 days respectively. Litter weight at birth, 3,6 and 8 weeks of age were 230.4 ± 9.5g, 602.1 ± 35.6g, 1247.5 ± 81.5g and 1673.0 ± 112.3g respectively. Parity significantly (P <0.05) affected the number of mating to conception and litter birth weight. Litter weight at all ages were influenced (P<.01) by corresponding litter sizes at such ages. Sire neither had any effect on litter weight at all ages nor on any of the reproductive parameters studied. Litter size at birth was negatively correlation with gestation length (-0.08), number of matings to conception (-0.27) and average birth weight (-0.42).