Sterility in cattle of high genetic value: chance of obtaining offspring in assured thanks to in vitro fertilization
1997
Soom, A. van | Vanroose, G. | Kruif, A. de (Gent Univ., Merelbeke (Belgium). Faculteit Diergeneeskunde. Vakgroep Voortplanting, Verloskunde en Bedrijfsdiergeneeskunde) | Bols, P.E.J.
This study describes the results of in vitro fertilization (IVF) in 21 sterile donor cows of high genetic value, 16 of which had been treated with FSH before slaughter in an attempt to improve oocyte quality. A limited number of breeding sires (n=5) with a history of good fertilization results in vitro were used. A mean of 5.7 more or less 1.1 transferable embryos and 1.2 more or less 0.3 pregnancies per donor cow was obtained. Finally 15 calves were born and five pregnancies are curently ongoing and beyond five months. Eleven donors yielded at least one calf. Birth weights of calves were rather high (50.2 more or less 4.6 kg for Holstein and 51.1 more or less 3.1 kg for Belgian Blue breeds). The sex ratio was 87 per cent (males/total). In conclusion it can be stated that a cattle breeder has a 50 per cent chance of obtaining a calf from a sterile dam using IVF after slaughter. Problems with heavy calves and a deviant sex ratio have to be solved by improving culture conditions for bovine embryos
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