Alta genetics canada

Polled dairy cattle trace back as far as pedigree records have been kept. The polled gene in dairy cattle is dominant over the horned gene. Yet horned cattle are still much more prevalent in the global dairy population because few producers ever chose to select for polled cattle as part of their breeding program. This is because the real, economic paybacks of selecting for production, health and conformation traits has traditionally trumped the desire for polled genetics.

The more recent public awareness about dehorning cattle has made it another hot button topic in the industry. The naturally hornless cattle have gained popularity in recent years because of consumer opinion on the dehorning process, and the side effects they feel result from it.

This perception has driven producers to create more naturally polled animals than ever in the past. The pros of polled genetics

It’s a fact that consumer perception directs many aspects of the dairy industry’s reality. Animal rights activists have criticized dehorning for years, but it hasn’t been until recently that the general public has joined the activists’ view on dehorning as a detrimental process. With increased awareness about this common farm chore also comes increased consumer demands on how they feel farmers should handle it on their dairies.

We clearly don’t want animals with horns running around dairies, so the question is whether to dehorn calves or breed for polled genetics. Unless consumers are willing to pay a premium for milk from naturally hornless cattle, you will likely be leaving dollars on the table by selecting exclusively for homozygous polled sires if you want to ensure no animals are born with horns.

The basics of genetics tell us that since the polled gene is dominant over the horned gene, animals with one copy of the polled gene and one copy of the horned gene will not have horns, and a naturally hornless animal can be created in one generation. It also means it is easier to make more polled animals faster than if the polled gene was recessive.

If you’re starting with only horned animals in your herd, the figures below demonstrate your results mating cows to a polled sire. The table on the left shows that a homozygous polled bull bred to a horned cow will result in 100% hornless offspring. The table on the right illustrates that a heterozygous polled sire bred to a horned cow will result in only 50% polled offspring.

Eliminating the need for dehorning may seem like the right choice for your dairy. However, the genetic sacrifices you will make in order to get to that point cannot be overlooked. Whenever you add extra selection criteria to your genetic plan, you will sacrifice in other areas. Here are just a few reasons to think twice about selecting exclusively for polled genetics in your herd.

As the images above show, using a heterozygous polled bull will not yield 100% polled offspring. To get to the point of a completely polled herd, and to maintain it once you’re there, you continually need to use only homozygous polled sires. This may not seem difficult, but it leads to the next shortcoming of using exclusively polled sires.

Even though the number of polled bulls in active AI has increased substantially over recent years, the total number of sires providing that polled gene is still limited. AI companies will only bring in bulls at genetic levels high enough to help you make progress in your herd. And since selection for polled animals has only recently gained popularity, many of the polled bulls are closely related – either from a small group of elite polled cow families or with sires in common.

Most importantly, at this point in time, polled bulls, as a whole, don’t yet live up to the genetic levels of their horned counterparts. With polled as a strict selection criteria, you will miss out on the best sires, regardless if you select from the genomic or daughter-proven lists. When you figure the amount of production, health and conformation that could be lost by limiting your options to only polled sires, dehorning calves becomes even less of an issue.

As you set your genetic plan keep in mind the pros and cons of selecting exclusively for polled genetics. At this point, the overall genetic and performance levels of horned animals still outpace those of polled cattle. Modern dehorning methods minimize stress on calves, so when performed correctly and at the proper time, it should be almost a non-issue.