Milk Producer - April 2009 - (Page 40)

RUMINATIONS By Blair Murray Improving the odds In the right circumstances, using sex-sorted semen in virgin heifers can offer a financial opportunity nce considered a dairy farmer’s pipedream, sexed semen for artificial insemination has become commercially available from all North American studs on a select basis at a premium price. Although this semen greatly improves your odds of producing a heifer calf, it is fair to ask whether the extra cost is worth it. Sex-sorted semen debuted in 1989. That year, the first live offspring was born from a dairy animal inseminated with semen sorted by the flow cytometry process. The process consistently produced 90 per cent female offspring at that time. However, it severely reduced semen viability and quality. Also costly and slow, the sexsorting technology took another 10 years to gain commercial acceptance. Commercial applications and most research have focused on using sexsorted semen in virgin heifers. They generally have a better conception rate than lactating cows, and offer a better opportunity for return on O investment for your dairy herd. First-service conception rates using sex-sorted semen averaged 47 per cent for Holstein heifers and 53 per cent for Jersey heifers in a recently published research study. That’s 80 per cent of the rate achieved with conventional semen, according to the study, which looked into using sexsorted semen in 211 commercial dairy herds, mostly Holsteins and some Jerseys. Of the single births, 89 per cent were female. When researchers considered only those animals calving with a normal gestation length of 265 Ruminations is prepared by Ontario Ministry of Agriculture, Food and Rural Affairs livestock technology specialists to provide information you can use on your farm. As well as producing mostly heifer calves, sex-sorted semen could help reduce the incidence of calving difficulties and stillbirths. 40 | April 2009 | MilkPRODUCER

Table of Contents for the Digital Edition of Milk Producer - April 2009

Milk Producer - April 2009
Contents
Editor's Notes
DFO Chair's Message
Dairy Update
DFC Promotion
Industry Roundup
National Policy
Triumph Over Tragedy
Policy Update
Research
Applied Science
Ruminations
Markets
New'N'Noted
Back Forty

Milk Producer - April 2009