31 July 1998

Late pregnancy test for cows

A LATE pregnancy diagnostic test to ensure cows are still in calf at the 120-day stage is being made available to dairy farmers by Axients new laboratory at Rotherham, south Yorks.

One of two new tests launched last week by Axient, it is based on laboratory testing for oestrone sulphate, a hormone released only by a functional placenta, which can be identified in blood, milk, urine and faeces.

Testing a milk sample taken at 120 days post service is claimed to give 99.9 % accuracy. "If the test gives a positive reading – it is positive," says Axient vet Elizabeth Berry. With some foetal loss after the customary 30-day pregnancy diagnosis being inevitable, she says the late pregnancy test will prove an invaluable management tool.

Cost will be £3 a sample for a minimum group of 10 samples, £5 a sample for fewer than 10. This compares with an average scanning fee of £2.50/cow plus a £10 call-out fee at the same stage of pregnancy, but milk testing is less stressful, adds the company.

Axient has also launched a test kit to enable producers to check for antibiotic residues in milk. But, it was stressed, it should not be used to get milk from an antibiotic treated cow into the bulk tank early. The Penzym test kit gives a test result on a milk sample in just 20 minutes, and it is hoped to introduce an improved version which will take just five minutes to produce a result.

Only one treatment

Test developer Jacques Degelaen said just one treatment of one cow for mastitis could potentially contaminate 1m litres of milk at the dairy. He suggested the test should be carried out on cows that calve early, or in cases of outside label use of antibiotics when a check might be desirable. Individual tests will cost £2.20 for a kit of 20 tests – a total of £44 – plus £75 for a heating block, which is required for the test.

The DIY test is designed to detect the antibiotics most widely used in mastitis treatment, and involves placing a tube of milk in the heating block for 15 minutes and then comparing colour change against a chart.

This will allow dairy farmers to make quick and informed decisions on whether to allow milk from treated cows into the bulk tank, said the company.

The new lab will now carry out Axients analytical work. Future developments include cattle health schemes, genetic finger printing and a wider range of tests for both dairy and arable farmers, said the companys national business manager Rob Holliday.