11 February 2000

PROGESTERONE TEST ANSWER?

MILK progesterone testing may offer dairy producers a solution to improving herd fertility.

"Identifying and treating problems is often difficult, but trials have shown that progesterone testing offers a solution," George Mann of Nottingham University told producers attending an MDC Focus Centre meeting at Harper Adams, Shrops.

"If a cow is 100 days calved and theres no sign of oestrus, progesterone testing will identify whether or not she is cycling."

About 10% of dairy cows will start cycling, then stop, meaning there can be a period of about 40 days with no reproductive activity. "Often this cessation coincides with cows hitting peak yields, but progesterone testing would allow these problems to be identified earlier."

Another problem – prolonged luteal activity – occurs in about 20% of cows, when progesterone levels rise and then stay high.

"This can be because of a difficult calving which disrupts cyclicity, or through feeding protected fats – a problem that is growing in severity with increasing use of dietary supplements fed to help cows cope with high yields."

Dr Mann believes that progesterone testing concentrates producers minds on fertility. "It would mean fewer silent or missed heats, allow identification of problem cows, reduce semen wastage, support the vet and help the herdsman."

But he conceded that there was a lot of work involved in progesterone testing, and that there was a delay in turning results around. "Uptake of this technology is currently low. However, the more work we do, the more we see better results, so we are trying to transfer this technology into the dairy industry again."

In one 93 cow herd, progesterone testing cut the number of services/pregnancy by 0.2, reduced the calving index by 12 days and meant eight fewer cows were culled for infertility, saving a total of £6829, or £73/cow.

"Those results were obtained on a farm which wasnt doing too badly to start with. The producer did take nine progesterone samples a cow – a cost which isnt included in the savings calculation – but fewer samples could be used. Both DAISY and NMR offer testing services.

"Another future option is in-line milk progesterone monitoring, which is being developed at Nottingham University in conjunction with NMR. Its an MDC-funded project, and the technology should be available on-farm within the next five to 10 years."