22 November 1996

TEST HELP FOR HEAT DETECTION

MILK progesterone testing has secured impressive fertility performance, including a calving interval below 375 days and failure to conceive culling rate below 6% on one Yorkshire farm for five years running.

According to DAISY figures the average dairy herd in a 90-cow survey loses £76 a cow through poor fertility. But for Mr Pattison, whose 166-cow herd average 8100 litres, good fertility has earned him an average of £7 a cow over the last five years.

This is achieved by a high heat detection rate, and is helped by progesterone testing.

His North Yorks vet Mark Glover, Northallerton, receives reports from cow milk progesterone tests at the Willow Tree Farm four times a week. These allow him to check herd fertility before his fortnightly visits.

Using these tests Mr Glover can determine whether cows are cycling normally, are anoestrous or cystic.

Cows are sampled from 20-27 days after calving once a week. If over three weeks a cow has two high and one low test, she is cycling normally.

Once cycling normally, the next heat must be identified. Using the low test result as a marker, alternate day progesterone testing begins 15 days after the low result. The next low result indicates the heat is imminent within a day or two. Normal cows are then tracked until they have conceived.

Continual low tests – which can reflect anoestrous – are treated promptly so cows start cycling more quickly.n

Vet Mark Glover checks milk progesterone reports before fort-nightly visits to Willow Tree Farm.