Only one in five suckler herds in a recent EBLEX survey managed to achieve a compact calving period of 12 weeks or less. The advantages of a shorter period lie in the easier management of both cows and calves, as they are all at a similar stage of the production cycle, through simplifying feeding and husbandry practices.

The aim should be for a simple system where tasks are batched – calves can be dehorned, vaccinated or weaned in the minimum number of batches, for example. Repeating tasks for later-born calves increases labour costs, explains Liz Genever, EBLEX beef and sheep scientist,

“The survey highlighted a massive variation between herds for breeding and calving periods. Reducing the calving period relies on good cow management, getting them cycling quickly, plus a compact breeding period.”

Only 30 herds (14%) in the EBLEX survey had a maximum breeding season of 12 weeks or less. In general terms, 40% had breeding periods of 3-6 months and a further 40% more than six months. The variation in breeding period length resulted in almost a third (32%) of calves being born outside of 12 weeks from the start of calving. Just 35 herds (15%) managed to complete calving within 12 weeks.

The survey also found that farms with a longer calving period are likely to have a higher mortality rate. Late calves are born into an environment where disease has often been building up invisibly, even when management is excellent.

Older animals can pass disease on to younger calves, as their immune systems are less developed. The risk of scour from E coli, rotavirus, coronavirus, cryptosporidia and coccidiosis all increase for late-born calves and the risk of pneumonia is greater in batches of calves of mixed ages.