Beef breeding: getting to grips with AI

There are a number of reasons why AI can benefit your suckler farm. Using AI eliminates the need for stock bulls. While this is an obvious plus from a farm safety point of view, given the fragmented nature of suckler farms, we often have lots of stock groups and running bulls with all of these mightn’t make financial sense.

The big gain to be made from AI lies with the access to genetics it affords us. Your typical Irish suckler herd has an element of pick n’ mix about it when it comes to cow breeds, types, shapes and sizes. Opting for AI means we can pick and choose our sires to suit, and harness the potential from every cow. It is difficult to find a stock bull that will tick boxes both for producing replacements and terminal stock for sale or slaughter, and AI on a farm can do one, or both of these jobs.

Genetic gain should always be on our radar when we’re selecting sires. Serious cattle breeders won’t be the ones asking the AI technician for his or her recommendations when they arrive to serve a cow. They will have assigned a sire to each individual cow or heifer before the onset of breeding season. That said, it’s always good to get advice from AI technicians or advisers who have seen stock, or other farmers who have calves on the ground from the bulls you’re considering.

If you need replacements, target your best cows – these should be calving down at the beginning of the season – with maternal sires. Again, keep genetic gain in mind. Look at these cows that will be giving you your replacements and ask yourself what they lack. What would you improve about them if you had the choice? Milk? Are they too plain? Are they too muscly? Whatever their flaws, pick a bull that will fix them.

If we want to add decent milk we need to be opting for a sire with at least 8kg of a daughter milk figure. Putting shape on an animal will involve opting for continental genetics while an overly muscly cow may be nicely rounded off with straws from Angus, Hereford or Salers bulls. All the while, be conscious that we might have a male when we lift the leg, and opt for a carcase weight index value of 25kg minimum, if possible. This figure relates to weight for age and is a means of hedging our bets.

Conformation

When you feel you have enough replacement straws used, look to your beef or live sales. If your goal is selling weanlings, you need a bull that has five stars for conformation, being conscious of colour mixes. A finishing bull needs a good weight for age (carcase weight) figure (>30kg) and this will typically correlate with a good conformation value.

The general guide with calving difficulty is 8% of a maximum on mature cows and 5% on heifers. But for me this is a horses-for-courses scenario. If you’re a part-time farmer who might potentially miss some calvings, 8% might be too high for mature cows and your thresholds might be better at 5% for cows and 3% for heifers. A full-time farmer who’s calved hundreds of cows and is looking at producing a crop of show-stopping weanlings might use more difficult calved bulls because they’ve done so before and trust in the ability of their cows and themselves to calve them successfully. That said, the reduction in labour when calvings are easy and calves are vigorous is extremely rewarding.

One thing that AI also gives, which to date isn’t well chronicled, is the option to drive hybrid vigour or heterosis easily. Put more simply, crossbreeding. Heterosis is defined as the increase in performance above the mid-parent mean when different breeds produce offspring.

Research has shown that performance across various traits in cattle production is improved by between 10% and 20% where heterosis is exploited. The dairy industry here has largely adopted the concept, yet it is something that beef farmers don’t generally concern themselves with.

The Canadian beef industry has invested heavily in genomic technology that allows farmers to identify the best sires to match with dams based on the potential for heterosis in the offspring. Indeed, crossbred sires are common there. If you can’t decide between two AI bulls of different breed, opt for the one that isn’t in the mix already. Many farmers I talk to are surprised with the quality of the calves they get when crossing easy-calving Angus with heifers in a continental suckler herd. I always tell them that it’s heterosis at work.

In terms of heat detection methods, the vasectomised bull is untouchable as the best. By using him we are simply piggybacking on nature. Other methods work in a female-only scenario and while they do work well, they will never beat the bull. However, a vasectomised bull does have his obvious drawbacks. He’s more expensive, a potential source of disease into a herd and often a pain to manage during the off season if we haven’t got suitable facilities. That said, I haven’t come across a single suckler farmer who opted for a vasectomised bull and subsequently chose to backpedal for other methods. When fitted with an inked chin ball, he will mark the cows that he has served so that labour around heat detection can be reduced. In a new development this year, Moocall has brought a type of digital chin ball to market – the Moocall Heat. The device alerts a smartphone when the bull is mating a cow and keeps breeding records.

Vasectomised bull with chin-ball at Teagasc Grange. In terms of heat detection methods, the vasectomised bulls is the best.

For some, a vasectomised bull mightn’t be a reality and they must opt for things like tail paint and patches. These are also excellent if used and applied properly. Experience is that tail paint will work the best when it is topped up regularly and during the time in the breeding season when there is most activity. In truth, if you aren’t topping up tail paint every four to five days at a minimum, you’ll be scratching your head walking into a field seeing animals with half their paint worn off thinking, “is she, isn’t she?” Heat patches are more expensive than tail paint at €1 to €2 per unit, but very effective at all times during the breeding season. That said, if not applied correctly, you’re simply throwing your money on the ground, because they will fall off.