Cm. Bowles et Aw. Lishman, ATTEMPTS TO IMPROVE THE YIELD OF BOVINE BLASTOCYSTS BY INCORPORATING INSULIN, SELENIUM AND TRANSFERRIN IN THE IN-VITRO SYSTEM, South African journal of animal science, 28(1), 1998, pp. 30-37
The aim of the present investigation was to improve maturation, fertil
isation and blastocyst production rates by adding insulin (10 mu g/ml)
, selenium (10 ng/ml) or transferrin (10 mu g/ml) individually and in
different combinations to in vitro culture media. The experiment was d
ivided into three parts with the additives being included to: (A) the
maturation medium where effects on maturation rates and the subsequent
development of bovine oocytes were measured, (B) the fertilisation me
dium, assessing fertilisation rates and further development and (C) th
e culture medium where bovine embryo development was evaluated Seleniu
m, when added to maturation medium, significantly (p < 0.01) improved
maturation rates (80.4% vs 61.8%), fertilisation rates (68.0% vs 58.4%
) and the percentage of blastocysts produced (24.6% vs 11.5%). None of
the treatments had a beneficial effect on fertilisation rate or blast
ocyst production rate when added to the fertilisation medium. Incorpor
ation of transferrin or transferrin in combination with insulin and se
lenium in the culture medium, significantly (p < 0.05) increased the p
ercentage of blastocysts produced (35.3% and 31.5% vs 18.7%). Transfer
rin also significantly (p < 0.05) increased the percentage of blastocy
sts that hatched (21.9% vs 14.2%), indicating an improvement in the vi
ability of the blastocysts produced. By adding selenium to the maturat
ion medium and transferrin to the culture medium the in vitro producti
on of bovine blastocysts is improved.