By Dr. Nathaniel F. Makoni and Eunah Makoni, ABSTCM (Private) Limited
Dairy farming is a business and one of the factors contributing to farmers’ profitability is production of a calf, preferably female, by a cow annually at the lowest possible cost. A male calf does not have much economic value in a dairy enterprise. When properly reared, female calves eventually join the herd as replacement heifers, or can be sold for a premium as quality bred heifers. Female calves are usually born with lower birth weights than their male counterparts, thus, imparting calving ease (CI).
There are new technologies aimed at rapidly building efficient productive dairy herds including use of sexed or Gender Sorted (GS) semen. GS semen is semen containing sperms to produce more progeny of a desired gender with an average accuracy of 90%. In comparison, conventional semen produces progeny at a male to female ratio of about 50:50. Traditionally, GS semen would contain a lower concentration of sperm per straw; approximately 2 million cells compared to approximately above10 million for conventional semen. This is partly attributed to the damage during the sorting and other biological processes. Thus, the conception rate is usually 10 to 20% less with GS semen than with conventional semen, hence the recommendation to use it on heifers.
Fortunately, Sexing Technologies LLC semen sorting technologies are continuously improving. The improvements include upgraded sorting machines, removal of dead sperm cells which usually poison live sperm and use of buffers that pre-capacitate (the process the sperm cells go through before penetrating the female egg) the semen.
The benefits of using GS semen include:
4 % fewer difficult calving: Calving difficulties can increase days open as the calving animal requires more time for the reproductive system to recover. Easy calving allows calving heifers to settle faster into the milking herd, thus, likely resulting in higher milk yield as the cow is under less stress. With an easy calving the cow will likely have no future fertility problems usually associated with difficult calving.
Genetic gains: Prudent dairy farmers use performance records for their herd ranking and aim to breed from their best cows. However, if these cows produce bull calves, they will be forced to recruit heifer calves from the poorer performing cows as herd replacements. Thus, use of GS semen on the best cows of the herd can be a strategy to produce quality replacement heifers and to enhance genetic progress on the farm.
Increase herd size: GS semen gives producers the opportunity to breed replacements for the herd without having to spend large amounts of money on heifers and also avoid the associated risks of bringing replacements onto the farm which can introduce disease and undesired genetic traits.
Income diversification: With up to 92 % chances of getting heifer calves dairy farmers can produce extra heifers for sale.
In conclusion, the use of GS semen in artificial insemination services increases the birth of heifers on both beef and dairy farms, resulting in both faster herd growth, and rapid genetic improvement. Furthermore, it is important for farmers to understand that GS semen now comes as three different products of varying fertility that is, unpurified GS, pre-capacitated and cleaned GS Sexed containing 2 and 4 million sperm cells. Pre-capacitation and increasing sperm cells to 4 M concentration also results in fertility comparable to ordinary bull semen.
For more on GS/sexed semen contact +263 778223367 or +254 722700355 or email@example.com