Breed trends Factors influencing breeding decisions 5.2 The genetic makeup of the national herd reflects decisions made by farmers and those in the breeding services industry. 5.4 Dairy farmers also try to obtain maximum value from surplus calves that are not needed as herd replacements, and use them instead for beef production. If dairy cows and heifers are mated with beef breeds such as Hereford, Charolais and Limousin, the resulting calves command a higher price since they produce a better beef carcass compared with Friesian and Holstein dairy calves. Such practices have produced a high incidence of crossbred beef cows in the national herd. 5.5 AI allows cows to be inseminated by a bull with superior genes.
Many different bulls are available on the market.
Each has been progeny-tested for particular production traits such as milk yield, proportion of butterfat in milk, and ease of calving. The farmer decides which traits are most desirable for his or her farming purposes and buys in the appropriate bull's semen. 1 5.6 Until its demise in 1995, the Milk Marketing Board monitored genetic improvements in production traits of dairy cows, such as milk yield and butterfat. Farmers can use this monitoring service to compare production in their herds with the national herd. Despite the options available, when choosing a bull to sire calves, most farmers seek the same genetic characteristics.