Caithness beef cattle producer, Donald Henderson, Dunn Farm, is reaping the benefits of synchronised breeding and artificial insemination (AI) to accelerate genetic gain.

In doing so, not only has he been able to increase pregnancy rates and calf weights, but also reduce mortality and improve his work-life balance.

Donald runs a herd of 230 Simmental, Salers and Aberdeen Angus cross suckler cows calving in mid-May for nine weeks. He began synchronising using CIDRs and AI in 2019 on his heifers to tighten the calving block but has since extended to most of his herd following involvement in a Scottish study.

“We initially AI’d heifers to use an easy calving bull on them and keep the calving period tight. We also used on later calving cows to try and get them back in the cycle,” explained Mr Henderson.

Then in 2021, Mr Henderson was approached by Livestock Health Scotland and Zoetis to take part in a trial to record the outcomes from synchronisation using CIDRs and AI in beef herds.

“We had about 100 animals – 60 cows plus heifers involved in the study. Everything mostly calved to the first cycle and the results were pretty much as they had been in the previous two years.”

One hundred animals at Dunn Farm were bred between June and late July 2021 by synchronisation using CIDRs and timed AI followed by a sweeper bull or a normal stock bull.

The results found:

• Conception rate to AI averaged 58%, and overall pregnancy rates were superior in the AI group at 94% compared to 82% in the natural service group.

• Assisted calving and calf mortality were higher in the natural service group, with calf mortality from birth to weaning at 10% in the natural service group compared to 0% in the AI group.

• 72% of cows calved in the first three weeks when bred to AI, compared to only 15% in the control group.

• 10% of calving’s in the natural service group had to be assisted, compared to only 2% in the AI group.

• Calf weaning weights were, on average, 30kg higher in the AI group (280kg) compared to the control group (250kg).

Commenting on the results, Mr Henderson said: “In the study, our calves weaned 30kg heavier than those to natural service due to the extra growth and superior genetics. We are calving outside, and having batches of cows and calves means we can manage grass better.

“Breeding in this way means we also have uniform batches of bulls and fat cattle, which we can sell off the farm at a year old. Because they are in batches of a similar age, there are also fewer health problems as you are not mixing calves of different ages.

“The fact we are selecting superior genetics and producing more milky cows is certainly aiding growth rates. You could spend £6-7000 on a bull every year, but AI means you don’t need to, yet you still have access to the best genetics available.

“You also only need to save one or two calves a year by breeding easier calving animals and synchronising and AI has paid for itself.”

Mr Henderson added that synchronising breeding has also improved his quality of life. “Before, we would start calving in March and end in July, but now we are calving over six weeks reducing the labour and improving efficiency.

“Admittedly, there is a bit more work to it than just sticking a bull in a field, but we have self-locking yokes in the fields surrounding the main shed and have also got a cattle crate set up.”

Mr Henderson now AI’s all his heifers and 70 of his best cows yearly. Last year he sold any cows not in calf. A technician is used to AI and all cows are scanned six weeks after AI and again in November to pick up any caught by the sweeper bull.

“It’s also peace of mind when you AI, as we know about 60% of the animals will be in calf immediately with one shot of semen,” he said.

The results from Mr Henderson’s farm mirrored those of the two other farms involved in the study and highlighted the economic gains from synchronisation and AI.

Veterinary consultant Colin Penny from Zoetis said: “Breeding using AI is vastly underutilised in the beef herd, yet the economic gains, as this study showed, can be quite significant.

“AI not only allows you to breed using superior genetics by accessing animals with the best estimated breeding values (EBVs), but those animals born earlier are also finishing quicker due to their genetics and extra days growth.

“We’ve also seen higher pregnancy rates and lower mortality in the AI groups across the three herds, resulting in 14 more weaned calves per 100 cows mated. When calculating all the costs of AI and also removing the need for one extra stock bull plus the benefits from AI calf quality, we estimated the ROI to be £122 per cow bred,” he added.

Farm Facts

• 230 Saler, Simmental, Aberdeen Angus cross suckler herd

• 650 North of England Mules

• Donald farms with his brother Allan

• 600ha of grassland, arable and rough grazing.