9 November 2001

Electronic ovulation detection work stuck in the starting blocks

By Marianne Curtis

DETECTING dairy cow ovulation electronically, via the milking parlour is poised to enter the final stage of on-farm testing. But lack of funding is delaying research necessary to assess how the technique performs in a practical setting.

Work began two-and-a-half years ago at the Silsoe Research Institute, Beds, to develop an electronic method of detecting ovulation. Most producers currently decide when to inseminate cows by observing behaviour, but this can be inaccurate, says institute researcher Toby Mottram.

Attempts have been made by some producers to overcome these problems by using milk progesterone testing kits, says Dr Mottram.

"But these can be time consuming because they require 12-20 samples/cow/year to be taken and these must be sent to a laboratory to obtain results."

Time and effort could be saved if producers were able to detect oestrus via the parlour using an electronic system, he says.

Milk can be tested to determine progesterone levels, which indicate the stage of a cows oestrus cycle. The difference from existing progesterone testing systems is this can be done electronically, using a biosensor, says Dr Mottram.

Biosensors are fitted in-line in milking parlours and when milk comes into contact with them, antibodies on their surface capture progesterone molecules. This produces information about milk progesterone concentration which is converted into an electronic signal by the biosensor, he explains.

"The signal can be used in conjuction with a particular cows database – which contains information on previous tests – to predict ovulation.

"When producers enter a cows identification and calving date into a keypad, her milk will be monitored on appropriate dates and the display will indicate when she is about to ovulate, or whether she has an abnormal cycle requiring vet intervention or is pregnant."

Biosensors can detect 20 out of 25 ovulations, says Dr Mottram. "We have done a trial involving a robotic parlour using six cyclic and two pregnant cows. Biosensors were able to detect ovulation and pregnancy in these cows. However, the trial had to be curtailed due to foot-and-mouth."

Wider on-farm testing is essential to refine the technique, ensuring it works smoothly in practice and to work out its cost, says Dr Mottram.

"For trial work it is easiest to work on farms with milking robots and we are looking for interested producers to take part in trials. This would involve minor disruption when equipment is installed and a weekly visit by a technician."

However, lack of research money to put this technology into practice is currently a hindrance, he adds. &#42