Do-it-yourself AI may be less effective, says report
Doing your own AI may, on the face of it, save money compared with employing an AI company technician.
But unless technique is constantly reviewed, it could prove more costly in the long run through poor conception rates.
According to a report in last week’s Vet Record, DIY AI can be as much as 35% less successful than inseminations undertaken by AI company staff.
The study, carried out in Northern Ireland by staff from DARD’s vet science division and staff at ARINI, Hillsborough and AI Services, found that DIY AI was, on the whole, less reliable, although the small sample size made the data statistically insignificant.
In the report, author Maurice McCoy says success was measured in terms of non-return to heat within 100 days and subsequent confirmed calving.
To assess the accuracy of heat detection, farmers also collected foremilk samples from each cow at the milking after oestrus was detected for progesterone analysis.
The method of insemination – DIY or technician – was alternated daily, with all inseminations carried out to normal routine using semen of the farmers’ choice.
Analysis of progesterone levels in milk samples revealed heat detection to be a problem in some herds, with up to 40% of samples recording high progesterone levels, indicating cows not being in oestrus.
“The two herds with the highest percentage of milk samples with high progesterone concentrations at service had recorded the lowest conception rate over the preceding three years,” says the report.
However, while five of the six herds in the study recorded poorer conception using DIY AI, one did achieve improved performance by this method.
“This herd had a compact autumn calving pattern and focused heavily on fertility management over a short period of time,” the report says.
The best way to combat poor conception in DIY AI is to attend a refresher course, enabling operators to review their technique and correct poor practice, which can develop over time.
Genus’ Northern Ireland manager, Irvine McInstry, says the first thing farmers should consider is heat detection and whether cows to be inseminated have been calved long enough and are free of infection.
“Then, once it comes to AI’ing, it is essential the cow is properly secured.
The last thing you need is to be chasing cows around trying to inseminate them.
And equipment, such as scissors for cutting straws and AI rods, should be clean and disinfected in alcohol.”
And unless semen is properly thawed, it won’t be effective either, says Mr McInstry.
“It should be at 35-37C and should be thawed in a bath of water at that temperature, rather than being run under the tap.”
Overheating will kill semen and underthawing means it will be inactive, he adds.
The main priority in DIY AI is ensuring there is an accurate record of the semen stored in the farm’s nitrogen flask, says joint author of the report, Brian Kennedy of AI services Northern Ireland.
“When you don’t know what’s in the tank, the only way to find the semen you want is to take straws part-way out and read the name on it, but this means you’re constantly part-thawing semen, reducing the viability of it every time.”