OVARIAN STATUS OF NON-GRAVID SLAUGHTERED ZEBU COWS IN ZARIA: RELATIONSHIP WITH AGE, SEASON AND CARCASS WEIGHT

Abstract

OF 3,900 non-gravid zebu ovaries examined at 3 Zaria slaughter houses, 2,652 (68%) were active, Ovarian activity was highest during the rainy season and anestrus highest during the dry season (P < 0.01). Anestrus non-gravid cows and empty cows with active ovaries had the lowest (135+41 kg) and the highest (170 +43 kg) carcass weight respectively. Aged anestrus empty COWS had the lowest carcass weight (127+28 kg) and mature empty cows with active ovaries had the highest (180 +47 kg). The incidence of anestrus increased with age. The magnitude of slaughtering of young and mature empty cows with active ovaries was discussed and it was recommended that rectal examination be done before culling animals in order to reduce this major source of loss of reproductively active cows.