27 July 2001

Focusing on intakes can correct fertility concerns

Fertility problems were tackled at this years British Cattle

Vet Association summer meeting. Vets agreed there were

no quick fixes, but improving management could help.

Marianne Curtis reports

CHECKING cows rumen fill and dung consistency allows a more rapid response to feeding inadequacies – which could be causing poor fertility – than body condition scoring.

Speaking at the British Cattle Vet Association summer meeting at the University of Leicester, Dutch vet and fertility specialist Dirk Zaaijer explained his method of monitoring dairy cows nutritional status.

"We are seeing an increase in abnormal oestrus cycles, decreasing pregnancy rate, extended calving interval and increased culling rate due to poor fertility."

Research showed high yielding cows in severe negative energy balance due to inadequate dry matter intake had low hormone secretion and a lot of abnormal cycles, said Dr Zaaijer. "Not seen in heat is one of dairy producers biggest frustrations and is an indication that cows are not healthy."

Body condition scoring was often used to support decision making when designing rations, he said. "Observing changes in condition score means you are always behind the problem because they take weeks to occur. Checking rumen fill and dung consistency reflects the current situation."

To check rumen fill, stand at the rear of the cow and look down her left side. When a hollow is observed or the area looks triangular, feed intake is poor, said Dr Zaaijer.

For lactating cows with adequate dry matter intakes, there should be no skin fold in from the spine and the rumen should bulge out, he added. Greater distension should only be seen in late lactation or dry cows, where feed stays in the rumen for longer.

Examining freshly dropped dung provides additional information about how well cows digest diets. "Faeces should be like thick custard, making a light plopping sound when dropped on the floor. The pat should be well defined and about 2cm thick. When you stand in it there should be no sucking sound when your boot is removed and no visible sole marks."

Faeces which is either thin and watery or too thick indicated a ration imbalance, he added.

Faeces should also be checked for undigested particles, he said. "The surface should be shiny with no particles visible. Using a gloved hand, it should feel like a creamy emulsion, with no particles." Dull faeces, with visible particles means the ration should be revised, said Dr Zaaijer.

Monitoring cows for rumen fill and dung consistency alongside a pregnancy diagnosis programme, should be a team approach between producer, vet and nutritionist, he advised. "This can provide information to allow a speedy management reaction."

IMPROVING FERTILITY

&#8226 Involve vet and nutritionist.

&#8226 Check rumen fill.

&#8226 Inspect dung.