Production records of a herd of Friesian W N'Dama cattle reared on-station were examined to assess their potential for use as dairy animals in the tropics. In addition, the radio- immunoassay technique was used to measure plasma progesterone concentrations to determine the attainment of puberty and resumption of ovarian activity postpartum in heifers and cows, respectively. A Friesian bull was always used to serve females on heat. Bull calves were significantly (P< 0.05) heavier at birth than heifer calves; the respective mean (1SE) weights being 3011 kg and 2711kg. The season of birth also significantly affected birth weight with calves born in the wet season being heavier than their dry season born counterparts (wet = 3111 kg; dry = 2611 kg; P