Science News 27/11/2011

Artificial insemination of cattle

With the continuous technical evolvement of agriculture, farmers are more and more adopting new techniques also when it comes to cattle breeding. Frozen bull semen and with it artificial insemination techniques are on the rise.

But what factors do breeders need to consider and what are the advantages and eventual risks?

Firstly, genetic change in herds can be speed up enormously by the use of AI (short for artificial insemination). By freezing and thawing cattle semen of a bull with strong genetic features (e.g. abundant milk production, good bones, strong legs etc.), the semen can be sold worldwide and hence the positive genetic traits can be reproduced in thousands of calves instead of the ten that the bull would naturally produce by mating with the cows in his local area.

This way, the bull’s semen and hence his genes can be spread internationally and simultaneously, correcting weaknesses in the herd and passing on the characteristics of the selected sires to their many daughters. With the genetic information being passed on by generations, cows get continuously healthier and stronger. When then testing the performance of the daughters, statistics can prove the actual performance of the bull’s genes which can lead to the “proven sire” status – an extreme economic advantage for the breeder.

However, there are some drawbacks. Determining when a cow is fertile is extremely difficult and the bull’s ability to detect the cow’s pheromones remains unique. Also, frozen semen is very often less potent than that of a bull.

As a consequence, many farmers have adopted a combination of artificial insemination and natural matings to have the herd calve over just a few weeks.

Today, the most prolific dairy cattle breeds are Holstein, with numerous frozen semen suppliers and artificial reproduction service providers gaining popularity

di S. C.