I THOUGHT I would use this article to reflect on our breeding period and how we have performed against the targets we set ourselves.

Fertility is such a driver of profitability in any dairy system, but for a block calver it is everything and there is no hiding place if we get it wrong.

We are working our way well through breeding time now. Of our three-month serving block, we are now towards the end of month two. There is still a bit to do, but we can now look back on the crucial first few weeks of artificial insemination and judge how well we have done.

In a perfect world, we would have four heat cycles within those three months. Mr Perfect would serve 100% of the cows in the first three weeks, have a conception rate of around 60%, and by the end of four cycles have virtually everything in calf.

Unfortunately, it is not a perfect world and we are certainly not the Perfects. The first area of disappointment this year was at the pre-mating vet inspection. We checked everything a week prior to the start of serving to detect any problems with cystic ovaries or metritis. We wouldn’t normally expect many problems at this stage, particularly as calving had gone fairly smoothly and we had few issues with retained cleansings or the likes.

This year, for whatever reason, we had around 25 cows with issues. Unfortunately, by the time you treat these animals, they tend to miss the opportunity to be served in the first three weeks. In future, I think we will bring the vet check forward a couple of weeks to give more time to correct any issues.

That, combined with the fact that some later calvers are not ready to serve, then inevitably there are some cows that either don’t cycle or don’t show heat, meant that we served 200 cows out of 250 in the first three weeks. The benchmark for a block calver would be 90%, so definitely ‘could do better’ material. I don’t think any failure in heat detection is behind this issue. We put a lot of effort into cow observation and we also now have an electronic heat detection system. This has been useful, but certainly not a game-changer. Occasionally it will flag up a cow that was bulling that we have missed, but it can also tell porky pies and I would always check each cow’s activity graph on the system just in case. The biggest benefit is that it highlights the optimum time period to inseminate each cow. The downside of that is that we end up serving cows at all hours of the day.

Our target is to get at least 65 replacement heifer calves born each year. We therefore buy what we think is enough black and white semen to achieve that. That semen is used up in the first three to four weeks. It gets used on the better end of the herd, with the rest served with beef semen.

The second area for frustration has been our conception rates. For the previous three years, we have experimented with a mix of sexed and conventional semen. Conception results with sexed semen have been mixed, but then you have to balance that with the fact you can be more targeted about which cows to take replacements from and you don’t have so many low-value black and white bull calves.

Because sexed semen has been tinkered with during the sexing process, it needs to be handled more carefully and more effort made to inseminate cows at the optimum time. Some people with particularly higher yielders claim they get as good conception rates with sexed as with conventional semen. This year, I decided to ‘man up’ and go 100% sexed semen. All I can say is that I am still far from convinced that sexed semen is the answer for us on our system.

We can consistently achieve the desired 60% conception rate with beef or conventional semen. With sexed, I would find 50% acceptable. Unfortunately, the reality is around 40%. What frustrates me most is the variation between bulls. Some bulls can do 60% no bother, while others are down under 30%.

For that reason we now work with a team of nine different bulls, buying only 20 straws of each to spread that risk. To rub salt in the wound, though, what really bashed the numbers this year was that one bull appears to have only one cow in calf out of 20 straws purchased. I cannot put in print what I think about that!

The last couple of years we have used Wagyu semen for the beef job. The attraction is that there is a fixed price contract, for bulls and heifers, and it lets us get a batch of calves away at between two-four weeks, and as a result takes the pressure off the system when we are at our busiest with calf rearing. I had heard mixed reports about Wagyu calves, but we have found them fine to work with and I would describe them as being like a plainer Aberdeen Angus.

Once that intensive month of AI is finished the Aberdeen Angus bull goes in. It is a big ask of a bull to get thrown in to tidy up in a block-calving environment. Arguably we should have at least two bulls, but the one we currently have is an awesome worker and, as long as his feet don’t go wrong, he seems able to hold his own.

That said, we always follow round behind him and AI everything with Aberdeen Angus semen as well. I don’t know how much we improve conception rates by doing so, but between us we appear to be getting two-thirds of cows holding in the second breeding cycle. The bull always looks rather offended that we follow behind him, but I’m afraid it is just too important that we get these girls in calf and we just can’t risk the day that something goes wrong and he doesn’t do his job. By the time you read this we will have pregnancy diagnosis results back from our last milk recording and we will have scanned our bulling heifers. Doubtless there will be a few disappointments to come in those, but, even allowing for that, I estimate that we could have around 200 cows in calf within the first six weeks.

This is the critical KPI for a block calver, and at around 80% that puts us in the ‘just about OK’ band, which I would take considering some of the aforementioned challenges. So, it is getting towards the final cycle in the serving block and last-chance saloon to get in calf.

I hate losing good cows out of the back of the block. Our final target is to have an empty rate of less than 10%. So, Johnnie Bull and I better keep to the task for one final push and see if we can tidy up as many of the stragglers as we possibly can.