Evaluation of a modified GnRH-based timed-AI protocol associated with estrus detection in beef heifers inseminated with sex-selected or conventional semen

This study also determined if the expression of estrus before timed-AI (TAI) would be associated with increased P/AI in acyclic heifers inseminated with conventional semen. Heifers (n = 1690; 320-523 kg of body weight, and 13-15 mo of age) at three locations over 2 years were scanned by ultrasonography to determine cyclicity (presence of luteal tissue) and reproductive tract normalcy.

Source: Theriogenology - May 30, 2018 Category: Genetics & Stem Cells Authors: M.G. Colazo, P. Whittaker, K. Macmillan, D. Bignell, G. Boender, R. de Carvalho Guimaraes, R.J. Mapletoft Source Type: research