Fixed-Time AI in heifers: Friend or foe?

Phil Holmes, 30/06/2022

Phil Holmes

Veteran NSW agribusiness and breeding advisor Phil Holmes explores the use of fixed time AI in heifers – a hot topic across the beef industry at present…..




CURRENTLY, there is much discourse on the use of Fixed Time AI (FTAI) in beef heifers.

In my opinion, it is mostly promulgated by those who will derive revenue from the process, and their timing is impeccable.

With average bull prices soaring to new heights in many breeds, FTAI can appear to be an attractive alternative. However, as always, a few questions need answers.

For those not yet familiar with the topic, the basic premise is to take all your maiden heifers and, through the use of drugs, synchronise them to demonstrate oestrus on the first day of mating.

The technician then arrives and AI’s the lot. Backup bulls are then introduced to mop-up those heifers that did not conceive to AI. You will need 2pc bulls for this anyway because of the concentration of oestrus activity.

The primary claimed advantages/benefits are:

  • Bull costs for the heifer mating will be reduced.
  • Improved genetic gain from using superior bulls in AI will improve herd performance in the long term.
  • Calves from the process will be born earlier and will be heavier at weaning.

There may be others, but the above seem to me to be the main ones. I have only the protocol that my mob (beef clients) use to query this issue. Most of it is well-grounded in science and economics, and some of it is anecdotal where hard data does not exist (for that I apologise).

The problem is that my mob think and act very differently to the majority of beef producers and what is to follow may be too big a pill to swallow.

Bull costs

We monitor this closely and keep good records so that we can report back every three years to the preferred seedstock suppliers when the supply contract is renewed.

Our metric is bull cost per calf born. In other words, every weaner has a price tag on its head as a function of the bull getting it there. Here is how it works:

Let’s say you buy a bull for $10,000 and syndicate mate to 50 females per annum, he achieves a weaning rate of 90pc, thus 45 weaners per annum.

If he is good enough to last for four matings (too many bulls don’t), he will sire 180 weaners in his working life. He has a residual value of say $2000 in the saleyards when he is done.

Therefore, the net bull cost is $8000 and this produces a bull cost per calf born of just under $45. If you pay $20,000 for that same bull, the bull cost per calf born is $100 and for a 200kg weaner, that is a cost of 50c per kg of liveweight.

We try to avoid all this nonsense by setting an upper limit of $30 per calf born, which is achieved mainly by avoiding bull sales like the plague and entering into a purchasing contract with preferred suppliers.

We avoid bull sales unless we are jammed, despite there usually being a barbie and a few beers afterwards and the chance of a happy snap that will appear in the rural press.

We just cannot work out how to come away from the sale on budget and on bull specs. Any advice would be welcome.

If the supplier is well above our $30 benchmark, we either negotiate the contract price down for the next three years, or walk away from the arrangement before it falls apart. In 40 years of doing this, we have only had to walk away once from a host of seedstock suppliers.

Fixed Time AI

Now let’s turn to Fixed-Time AI.

My research suggests that $60 per heifer inseminated is a fair representative cost and this includes the cost of the semen and the drugs, but not the time and cost to the owner of organising it all (and the yard-work).

The next issue is the AI conception rate. Really good AI technicians will palpate the ovaries before insemination to determine which ovary released the egg, and they will then deposit the semen into that uterine horn. These technicians are rare, as most deposit the semen just beyond the end of the cervix and it could go anywhere.

The good technicians achieve conception rates of around 60pc, but a fair and reasonable industry-wide conception rate would be 50pc.

So, our $60 cost per insemination now becomes $120 per weaner ($60/0.5). This is $20 more than the $20,000 bull in the example above, which in itself was bordering on madness. If you achieve a 60pc conception rate to AI, the bull cost per weaner is $100, still way, way above an economically sensible target.

But is does not stop there …

The drugs used to synchronise the heifers for AI interfere temporarily with normal cycling after AI, and conception rates to the backup bulls suffer. If you talk to those technicians who both AI and pregnancy scan, you will learn that the backup mating will add about another 20pc to the overall total number of weaners.

So, if you achieve a 60pc conception rate to AI, you can expect to wean about 80pc; if it is 50pc to AI, it is 70pc.

My mob confidently expect about 88pc weaners for a six-week heifer mating (this is net of losses to dystocia). For FTAI, that means either 8pc or 18pc fewer weaners.

What is a weaner worth? It now gets really murky and complex, but to keep it simple, let’s just assume $2000 when sold. For 100 heifers artificially inseminated, that represents either a $16,000 or a $36,000 impost.

Improved Genetic Gain

The example is often put forward that instead of using a live $20,000 bull, you can be using semen from a $100,000 bull and genetic gain will increase.

This is, of course, complete nonsense. What makes a bull worth $100,000, true genetic merit or market forces? If it is true genetic merit, the argument falls apart immediately. If a bull is truly superior genetically, in short time, he will breed a son or sons better than he is, thus seriously discounting his market value.

If he cannot do that, he is almost worthless. Crazy prices for ‘Super-Bulls’ are a serious distraction to profitable beef production, either at the commercial or seedstock level. This stuff is a semen sale and marketing play, and nothing much to do with profitable commercial beef production.

As well, how are you going to select this ‘Super-Bull’? What evidence are you going to use? If you get it wrong, you may pay for it for years to come in the herd. Solid evidence on this decision is hard to find and the choice is both complex and difficult, especially if overseas sires are looked at.

Ask serious and competent seedstock producers about this.

Most of the bulls that we purchase under contract are in the top 10-15pc of breed on our preferred index, and we are happy enough with that.

Early Calves

Yes, there is no doubt that the earlier a calf is born, the heavier it will be at weaning and that advantage carries through until sale in the majority of cases with steers.

My mob have a different approach. We start off with a six-week mating for heifers, along with the whole herd. In that mating, around 70pc of the calves are born in the first cycle. After a while, we move to a four-week mating, moving ultimately to a three-week mating.

This is moving off-subject for a tad, but you have to reduce the number of calves born to heifers, otherwise the whole herd structure gets out of kilter over time; too many young females. How you do this is important and it is not with a drafting stick in the yards. That’s a story for another day.

This gives us lots of early-born calves and lots of growing time until weaning. As well, it provides more time for their mothers to resume cycling after calving.

The beauty of this system is that it is sustainable year after year at low cost and does not require a drug-induced program to make it happen. It also has seriously big advantages in the time and cost of calving supervision in maiden heifers.


We have tried hard, but we cannot make the numbers stack up for Fixed-Time AI in our system – but happily admit that the numbers may well work in other systems. This is a classic example of the technical aspects of the science being rock solid, but the economics found wanting. Both must stack up concurrently for us to get seriously interested.

This current bull price madness will pass, as it is unsustainable. The priority for us is to keep cool heads and be rigorous in our thinking while we wait.





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  1. Ian, 05/07/2022

    Keep poking the bear Phil at least you are making some people think, why would you worry about indexes which is mythical figure which can;t be validated

  2. Desiree Jackson, 05/07/2022

    This is an excellent article by Phil – concise and to the point, and in usual Phil Holmes fashion, direct and straight to the point. The bull cost calculator is refreshingly easy to use and quickly provides feedback on the bull cost for each calf produced. The other consideration is the fecundity of the bull and not having his working life cut short through injury, death or some other misdemeanour. Thank you Phil for this great article.

  3. Rach, 02/07/2022

    When an article champions the use of data and economics, I would expect the article to use actual data to back that argument up instead of loose assumptions… so I have questions. If genetic gain means nothing and models using this to factor in $$ gained are considered useless (as indicated in the article with $100,000 bulls), does that also mean we scrap EBVs? What about Genomics?

    There are many reasons for using FTAI, not just those proposed in this article, as noted by Dr. Jephcott. Farm management practices are changing and so are farming families and their business goals. Totally discounting a technology or management practice because it does not fit the model you like to use with your own clients does not mean it is the wrong choice for others. For some farms, feeding oats works, does this mean we should all do it? No. It just means it works for them and what they are trying to achieve.

    There are so many variations when it comes to breeder management and programs for AI, it is far more complex than comparing a singular system to bulls in the paddock and backing that particular horse in.

  4. Dr+Sandra+Jephcott, 01/07/2022

    I am guessing that my comments will not be published. As with Phil holmes, I am also a livestock veterinarian. Phil is more intensely focused on the business aapect of livestock production whereas I have beem employed as Head Veterinarian for large pastoral companies in Australia and Russia, I have also been a managing owner for beef cattle businesses in Australia and Paoua New Guinea. My role has been for the health, wefare and productivity of the cattle under my care. Phil’s assessment of activities such as FTAI is very cut and dried. He adopts a similar role in Bush Agribusiness reports. Livestock properties are people’s homes as well as their businesses so activities such as FTAI are not always a black and white approach. There are many more reasons why people use FTAI than what Phil has outlined and his costs are not always the same. FTAI cannot be simply thrown out the window.

  5. Richard+Golden, 01/07/2022

    As always Phil, logical conclusions from rational thought and hard experience.
    We have tried trigger drugs and natural service and proved it doesn’t give financial and herd structure gains.
    We didn’t even try the AI tech route.

  6. Rob Mackenzie, 01/07/2022

    Well written and researched article To lower bull costs breed a few of your own all you need is a scrotal tape measure and scales

  7. Sarah Wrigley, 01/07/2022

    If you’re an average size breeder, how do you purchase bulls in the top 10 – 15% of breed for your preferred index ‘under contract’? I actually agree with Phil regarding the ability to get most calves up at the front of the calving period with a natural mating, but am not sure how to procure the good bulls on a budget.

  8. Paul+D.+Butler, 30/06/2022

    Phil Holmes offers common sense and rational thoughts rather than just the standard propaganda.

    • Rach, 07/07/2022

      I would argue that propaganda can be looked at from both sides and there are also those who have a lot to gain by advising on bull buying, breeding and general management of natural mated systems. At the end of the day, it is not about which system is the be all and end all, but instead, which system fits your specific business model. You cannot make blanket statements without any supporting data and expect that to be accepted and suitable for everybody.

  9. Greg Brown, 30/06/2022

    Great article Phil. Should be heeded by the whole industry

  10. Andy, 30/06/2022

    Spot on great article Phil
    This hysteria over ft AI is over the top and I can’t get the numbers to add up

    Tighten up your heifer mating period
    So simple and effective

    I just wish the bulls lasted longer then the price per calf would be far cheaper

  11. Mike Introvigne, 30/06/2022

    Your whole article hits the mark, well done.

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