8 June 2001

DIY enthusiasts cause of poor dairy herd fertility? caus

By Richard Allison

IMPROVING insemination technique and heat detection could reverse the decline in dairy cow fertility seen over the past 10 years – the equivalent to reducing calving interval by 10 days.

Differences in fertility between the top and bottom 25% of herds equate to £18,000/year for a 100-cow herd, said Genuss Drew Sloan. This extra cost is due to a 40-day longer calving interval, 5% higher replacement rate and the extra semen used.

"The cost of poor fertility led us to review published data to identify how fertility can be improved on UK farms. Poor heat detection and AI technique were found to be two key factors, but it was clear that insemination technique had not been evaluated in the UK."

To fill this gap, Genus examined data from 85 producers attending DIY AI refresher courses over three years. "Post-mortem analysis showed 25% of DIY inseminators damaged the uterus sufficiently to impair fertility," said Mr Sloan. "Nine ex-AI technicians also attended the course and caused no damage."

The correct placement of semen in the uterus is crucial for successful conception, added his colleague Mark Smith. "From the 1152 cows inseminated on the courses, 45% were inseminated correctly, but 22% did not even have semen placed in the uterus, so had no chance of getting in calf.

"This could increase the conception rate from 40% to 60% on many DIY farms in the UK."

Mr Smith said NMR and Genus data from 2200 farms supported the findings, with DIY herds having a four-day longer calving interval compared with technician serviced herds. This was found for both average and high yielding herds.

"But 25% of producers did match the accuracy of professional technicians, indicating that, with correct training, DIY insemination can be just as good."

Where fertility is poor for DIY herds, Mr Sloan advises producers to consider brushing up on their AI skills by attending an abattoir-based course or using AI technicians. "Some producers would be better off spending their time on heat detection and using AI technicians."

To help producers improve cow fertility results, Genus has launched a Reproductive Management Service. This will provide daily reports, allowing the targeting of cows for observation.

"This free service will be available to producers who use Genuss AI technician service. This is because AI technicians can update records for producers using insemination details, so cutting paperwork." &#42

DIY INSEMINATION

&#8226 Poor technique can harm uterus.

&#8226 Crucial to place semen correctly.

&#8226 Consider AI refresher course.