Controlled Breeding — Artificial Insemination and MOET

Rather than leaving reproduction to chance natural mating, livestock improvement programmes increasingly rely on controlled breeding techniques, of which the two most important are artificial insemination and MOET.

Artificial insemination involves collecting semen from a male selected for its desirable traits, and then introducing this semen directly into the female's reproductive tract using an instrument, rather than through natural mating. This means the semen of a single, genetically superior male can be used to inseminate a very large number of females — even after being transported or stored — spreading his desirable traits far more widely through a herd than natural mating ever could, without needing to physically keep or move a breeding male to every farm.

MOET (Multiple Ovulation Embryo Transfer) is a technique that lets a single, genetically superior female produce far more offspring than she could by normal pregnancy, through a four-step protocol: (1) the donor cow is given hormone treatment (a follicle-stimulating hormone-like preparation) to induce superovulation, causing her to release six to eight eggs in a single cycle instead of the usual one; (2) she is then mated with a genetically superior bull, or artificially inseminated; (3) a few days later, the resulting early embryos are non-surgically flushed out and recovered from the donor's uterus; and (4) these embryos are then transferred into a number of surrogate (recipient) cows, who each carry one embryo to term as their own pregnancy. In this way, a single outstanding donor cow can produce many calves within a single year rather than the usual single calf, dramatically speeding up …