Embryonic death and methods for its reduction in meat cattle
2007
Baitlesov, E.M. | Kanatbaev, S.G. | Nasibov, F.N. | Titova, V.A. | Khikevich, S.N. | Tyapugin, E.L.
The relationship between the embryonic mortality (EM) in beef cows and season, insemination time and breed is considered. Progesterone was estimated for the influence of administration time after insemination on the effectiveness of fertilization, as well as its analogs – surfagone and human chorionic gonadotropin (HCG). The indices of efficacy of 100 single inseminations were analyzed in the dynamics of EM at early pregnancy, their total index being 52%. The main embryonic deaths were found to fall on days 10 and 20 after insemination reducing to 10% by day 50. They were inconsiderable for first-calving heifers and cows of 5-7 lactations. Most cows inefficiently inseminated come into heat again after 26-28 days being a sign of death of an embryo at day 16 of embryogenesis. EM reached on average 31.8%, the occurrence of embryonic deaths in summer reached 40%, in winter-spring period – 28% and autumn-winter – 24%. The best effect of insemination in cows was gained when progesterone was administered at days 6-8 after the first insemination. The efficacy sufragone and HCG administered at days 7-10 after insemination was in line with progesterone. It is concluded that the use of these preparations may be considered as an alternative of progesterone.
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