Most livestock producers in the central and northern interior are emerging from a severe drought cycle that dragged on for approximately three to four years. These droughts had a far-reaching consequences for livestock numbers and most herds were reduced to core herds. The drought indirectly assisted producers in selecting only the best female animals adapted to their area and farming system – the reproductive and problem-free animals with good composition were retained, while the passengers were culled.
Now our female herds must be rebuilt and there are only two ways of doing this, namely buying or breeding. In my opinion this is a golden opportunity to improve the quality of one’s herd. Buying is a quick way of letting a herd grow, but it does come with some definite risks in respect of health issues, especially sexually transmitted and other infectious diseases.
Breeding, on the other hand, is a much slower process with visible results only seen after three years. Nevertheless it is a much better option – not only with regard to health, but also in respect of adaptability and production traits. By using artificial insemination (AI), a genetically superior next generation can be bred with more certainty. AI offers the further advantage of calves and lambs being born in concentrated groups, making management and selection much easier.
Genetically superior animals
Each population has its share of genetically superior and weaker animals. A population can be regarded as an age group, herd, breed or national herd. If an animal is genetically in the lower third of a population, it will struggle to produce progeny that will perform in the top half of the population.
It is therefore crucial that genetically superior animals are improved even more by using other genetically superior animals. Once again AI will enable you to mate your best animals with tested or genotypical young bulls for greater genetic progress and greater reliability.
The dairy industry is a few steps ahead of the meat industry when it comes to the use of genetic breeding values in selection and breeding policies, but there are still enough breeding values for genetically important traits in most meat breeds for stud and commercial beef producers to make genetic progress with a reasonable degree of reliability.
Regardless of whether one breeds pure-bred animals or crossbreds, it is still important to decide on a breeding policy or objective and to actively pursue it. Because genetic progress is slow, it takes approximately three generations (with cattle this period represents ten years) before any real progress can be seen.
All producers – whether stud, commercial, purebred or crossbreeding – regard certain traits as key to their economic survival. In my view, reproduction or fertility is the single most important trait, because without growth there is no product to market. After fertility, production traits are also important for both milk or meat production.
The simplest way to evaluate reproduction is through the inter-calving period (ICP). All breeds that partake in performance testing, use it as the basis of their reproduction index. Unfortunately fertility has genetically low heritability (h2 = 0,05-0,11). Hence, repeated selection for this trait over successive generations is necessary in order to show progress.
There is no doubt that genetically more fertile female animals are the most productive and profitable animals in a herd. A cow with an ICP of 384 days over eight calves, will produce one calf more in her lifetime than a cow with an ICP of 424 days over the same period.
Female replacement animals
When breeding female replacement animals, it is important to combine fertility with adaptability and production traits. If one repeatedly puts too much emphasis on e.g. weaning weight and growth, you can lose in respect of milk production and fertility.
I believe that a good bull for this purpose, is one with positive breeding values for these traits, without excessively placing one above the other. AI allows you to use these genetically superior bulls in your herd, and ensuring an investment in the next generation. – Dr Anton Smit, retiring CEO of Taurus Evolution