This week we'll be having another South African Dorper inspector to visit, as we are keen for him to look at our weaner lambs and to give us some guidance with our ram selection for joining later in the month.
One of the breeding strategies that breeders use in their studs is corrective mating: this is where animals are combined where one animals excels in an area where the other is weak, with the goal of correcting the weak point and creating more uniformity within the flock. An example of this is selecting a ram with a very good head that conforms in a superior way to the breed standard and using that ram to improve the quality of all the heads in the flock. The same principle can be used to improve other traits such as shedding. However, the breeder must always be careful not to focus on one single trait at the expense of another.
Line breeding is also used in most studs to increase the incidence of good genetics, where animals are bred that have related ancestors. The aim of this is to increase the uniformity of the progeny. Line breeding creates the most genetic gains in a flock, but has the problem that, in attempting to increase the incidence of good genes, there may be some defective genes that also accumulate and this can result in problems with future generations. Hence the old saying: "It is called line breeding when it works and inbreeding when it doesn't". If the line breeding is too close it can also impact negatively on growth rates and fertility.