Lactational characteristics of imported British Friesian cattle in Western Nigeria

Abstract

SummaryDuring the period 1962–73, the majority of the 92 lactations of imported British Friesian animals were initiated during the dry season (October–March). The following average values were obtained: lifetime number of lactations, 4·5; lifetime milk production, 9392 kg; age at producing first live calf, 39·6 months; milk yield of nine lactations, 2159 kg; lactation length, 336·5 days; daily milk yield, 6·3 kg; 305-day milk yield, 2012 kg; dry period, 173 days.Milk production was highest in the fourth lactation when the animals averaged 7 years old. Differences in milk yield among lactations were small. Peak daily milk yield was greatest in the third lactation and was reached within the first 21 days of each of the first four lactations. A second but lower peak with the highest milk production persistencies at a later stage of lactation apparently depended on feed availability. The 305-day milk yield was reasonably predicted from the 100- and 200-day yields.Lactations subsequent to abortions and stillbirths were slightly longer, gave less milk (P> 0·05) and were followed by longer dry periods than those initiated by normal births.