Responses to supplementation in white Fulani cattle under agro-pastoral management in northern Nigeria. 1. Phosphorus.

Using on-farm supplementation trials with a P rich block (Phos) and a salt block (Salt), deficiency of P in White Fulani cattle in Nigeria was investigated. There was some evidence, significant in some locations but nonsignificant overall, that P supplemented dams produced heavier calves and supported greater calf growth. Dam mean weight gains, 9 to 1 months pre-partum were 6.9 kg/month on Phos (s.d. = 5.0, n = 50) and 3.8 kg/month on Salt (s.d. = 4.7 n = 54) (P > 0.05). Overall least squares means of calf weights at 12 months were 105.2 kg (n = 29, s.e. 9.3) on Phos and 91.5 kg (n = 37, s.e. 6.3) on Salt (P > 0.05). In animals below 2 years of age, mortalities were 6.8% on Phos and 13.6% on Salt (n = 179, Chi-square P < 0.01). No response to supplementation was observed in older and non-pregnant cattle.