Supplementation of Slow‐Release Melatonin Improves Recovery of Ovarian Cyclicity and Conception in Summer Anoestrous Buffaloes (Bubalus bubalis)

The role of melatonin as a protective neurohormone against restoring cyclicity in summer anoestrous animals in photoperiod species has gained wider acceptance. This study was designed to uncover the evidence the slow‐release melatonin (MLT) has on initiation of ovarian cyclicity and conception rate (CR) in summer anoestrous buffaloes. Thus, buffaloes diagnosed as summer anoestrous (absence of overt signs of oestrus, concurrent rectal examination and radioimmunoassay for serum progesterone at 10 days interval) were grouped as untreated (Group I, sterilized corn oil, n = 8) and treated (Group II, single subcutaneous injection of MLT @18 mg/50 kg bwt in sterilized corn oil, n = 20). Animals treated and detected in oestrus were artificially inseminated (AI) followed by division into Group III (second dose of MLT on 5th day post‐AI, n = 8) and Group IV (no melatonin administration, n = 10). Blood samples were collected at 4 days interval for estimation of serum MLT, progesterone and oestrogen using radioimmunoassay kit. Mean oestrous induction rate (OIR), oestrous induction interval (OII), interoestrous interval (IOI) and CR were estimated. Compared to control, concentration of melatonin was significantly (p < 0.05) higher in treated group ranging from 14.34 ± 1.72 to 412.31 ± 14.47 pg/ml whereas other two hormones did not show any concentration difference. Melatonin‐administered buffaloes showed significantly (p < 0.05) higher (90%) OIR with OII of 18.06 ± 1.57 days. Results showed improvement in conception rate in buffaloes administered with post‐insemination melatonin. It can be concluded from the study that slow‐release melatonin supplementation restored cyclicity in summer anoestrous animals resulting in improvement in conception rate in buffaloes.     

Risk Factors for Kid Mortality in West African Dwarf Goats Under an Intensive Management System in Ghana

Breeding records from 1997 to 2000 for West African Dwarf goats kept under an intensive management system on the National Breeding Station at Kintampo in Ghana were analysed for the effect on mortality of sex, season and type of birth, and birth weight. The pre-weaning and post-weaning mortalities were 10% (n = 390) and 23.1% (n = 351), respectively, while the overall mortality from birth up to 12 months of age was 30.8% (n = 390). The post-weaning period recorded significantly higher proportions of deaths in males, females, single-born and twins, during the rainy and dry seasons, and for kids with low or high birth weight, compared to the pre-weaning period. There was significantly higher mortality in male kids than in female kids. The odds and risks of death for male kids were about twice those for females at post-weaning and up to 1 year of age. At pre-weaning and up to 1 year of age, a higher proportion of the dead were twins. Twins had approximately 2.5 the risk of death at pre-weaning, compared to singles. Also, kids born in the rainy season had significantly higher mortality than those born in the dry season. Kids that died by the time of weaning were significantly lighter in weight at birth than those that survived. Male kids had significantly higher mean weights at birth and at weaning, but not at 12 months of age. The significance of these findings is discussed.