Effect of parity on intake and utilization of a high forage low concentrate ration by Bunaji cows in early lactation
During the early lactation of three groups of four Bunaji cows each in the first, fourth and seventh parities, a 3:1 hay mixture or Cyonodon nlemfuensis variety robust us and Gliricidia sepium leaves fed ad libitum was supplemented for ten weeks with concentrate that supplied 16% of the daily total dry matter intake (DMI). On metabolic size basis, the intake of actual and digestible dry matter, crude protein (CP) and energy declined with increasing parity, the values for the seventh parity being significantly lower (P<0.05) than those for eal'lier parities. Aninmls in the 4th parity produced maximum fat-corrected milk (FCM), solids- corrected milk (SCM) and actual milk that contained the least total solids (TS), fat, and caloric value but highest solids-not-fut (SNF) and lactose · (P<0.05). They also most efficiently converted DM, digestible CP (DCP) and digestible energy (DE) consumed into actual milk, FCM and SCM and tbe nitrogen intake or absorbed into milk nitrogen. Differences in these parameters during the earlier and Inter parities were similar (P>0.05). On the average, animals in the 4th parity apparently lost or gained no weight. Primiparous animals gained one and half times as much weight as the oldest animals and more efficiently utilized the DM, DCP and DE consumed for weight gain while the ratio of their live weight gain to milk yield was higher (P<0.05). Multipnrous animals required 110% of the recommended CP but all animals i·equired 70 • 85% of the recommended DE Nigerian Journal of Animal Production 20 (1993) for maJntenance and productive purposes.
Key words: Parity, milk yield, weight gain, Bunaji, Cynodon, Gliricidia.