23 November 2001

Feeding management is key to improving fertility

By Richard Allison

MODERN, high yielding cows should not be blamed for the continuing decline in UK conception rates. Instead, feeding management should be re-assessed to improve fertility.

Dairy cow genetics have advanced faster than feeding management, said Merial vet Roddy Webster at a recent dairy fertility meeting in Somerset. "Maximising feed intake is one solution for combating poor fertility on some units."

During early lactation, cows are in negative energy balance and the first thing to suffer is fertility. The aim must be to minimise the period of negative energy by stimulating feed intake to encourage earlier cycling. The more cycles before first service, the better the chance of conception, he said.

"Bullying at the feed face should be kept to a minimum by aiming for group sizes of 50-60 cows. Freshly calved cows are most vulnerable, as they are weaker and have to fight off dominant cows for feed space. Remember that dominant cows are not always the highest yielders," added Mr Webster.

Feed trough position is also important with floor level feeding resulting in 17% extra saliva production and lower intakes than when cows are fed in raised troughs.

"Placing feed on rough concrete can also reduce intakes as their tongues rasp against the rough surface reducing time spent eating. A metal surface or other smooth surface is ideal," said Mr Webster.

Worm infection can also reduce intake by suppressing appetite. There is a common belief that cows are immune to worm infection. "In one survey, more than 83% of cow carcasses were found to have worms present in sufficient numbers to reduce performance." The problem is faecal egg counts are not always reliable, sometimes giving a false negative.

"Recent research has shown that worming heifers increases feeding time by 105 minutes/day."

John Downing, who farms on the Kent-Surrey border near Ednenbridge, added that the transition cow group is the most important group on-farm. Paying attention to these cows results in fewer problems at calving, which can reduce appetite.

"Transition rations are based on the high yield ration plus chopped straw, 250g a cow magnesium chloride and 100g a cow of dry cow-minerals. You cannot afford freshly calved cows to become sick and intakes to suffer when in negative energy."

&#8226 The evening fertility meeting was held at the Royal Bath and West showground and was sponsored by Holstein UK and Ireland, Merial, Cogent and CIS.