THE EFFECT OF USING SOME GROWTH PROMOTERS ON THE PERFORMANCE OF GROWING FEMALE CALVES

Abstract

In Egypt, Buffalo is well adapted to the environment and considered the most important farm animal. A critical problem with it is late first calving age. Previous studies indicated that using non­ hormonal growth promoters accelerated growth. The present study aims to assess whether this effect extends to reducing age at first calving, and to evaluate the economic benefit in farmer perspective. A non-hormonal promoter (Lacto-sacc) composed mainly of Saccharomyces cen•esiae was added to the ration on the base of 10-g promoterffreated Ration (TR). Three groups of animals (4/group) were used; the first was .given the TR 3 consecutive days per week, the second was given the TR 3 consecutive days per 2 weeks, and the third was left untreated as a control group. Monthly body weights from 6 months age to maturity were recorded. Blood samples were weekly collected for blood parameters determination. Cost of feed per Kg gain and the ratio between the price and the cost of this gain were used as economic indicators. Repeated measurements design was applied using GLM procedure of SAS (1990). Results proved that as average the treated heifers, compared to the control animals achieved puberty and conception {p<O.OS) age by 1.3 and 4.3 months earlier, respectively. Results proved higher (P<O.OS) average daily gain, better feed efficiency, and better economic efficiency for Tl than T2 or C, respectively. Furthermore, Results proved higher (P<O,OS) average daily gain, better feed efficiency, and better economic efficiency for Tl than T2 or C, respectively.