Abstract

MENEZES, L.M. et al. Reproductive performance of beef heifers exposed to different bioestimulation treatments. Arch. zootec. [online]. 2011, vol.60, n.232, pp.1347-1350. ISSN 1885-4494.  https://dx.doi.org/10.4321/S0004-05922011000400054.

The objective of this study was to evaluate the reproductive performance of beef heifers exposed or not to different sexual biostimulation treatments. Two hundred and twenty Aberdeen Angus heifers, 24 months old were used. Heifers were divided into three groups: group one, using teaser bull consisted of 73 heifers exposed, for 60 days previous to AI, to vasectomized males. The second group consisted of 73 heifers exposed during the same period to androgenized cows. The third group consisting of 74 heifers was the control group. After the treatments (60 days) started the breeding season. Variables analyzed were the weight at the beginning and the end of treatment, ADG, the pregnancy rate, and the interval between the start of breeding season and conception. Fixed factors considered were the three treatments. Heifers biostimulatated with androgenized cows had a earlier conception, (p<0.01) than thosed bioestimulated with teaser bull. Biostimulation can not change rates of pregnancy in beef heifers. The use of biostimulation with cows androgenized anticipates the conception in beef heifers of two years old.

Keywords : Conception; Pregnancy rate.

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