Many calf deaths could be avoided

Nearly half of all calf mortalities occur in the first day after birth, but many could be overcome.

Cathy Dwyer, behavioural specialist at SAC, told delegates the impact of calf mortality figures had been overlooked compared with other farmed species.

Sheep and pigs typically saw losses of 15-25% compared with 7.5% for dairy and 5% for beef.

“However, where other species may lose a newborn and others may remain, the loss of a calf often renders the dam unproductive.”

The main cause of mortality was difficult calving – or dystocia.

Poor cow condition and high calf weight were causes, but there was a clear correlation between human intervention at calving and mortality, said Dr Dwyer.

Studies from the EU and USA suggested calves were three to 15 times more likely to die after a difficult calving.

Neonatal losses (within 24 hours) increased dramatically from 1.2% for unassisted births to 35% where assistance was given using traction apparatus, such as calf pullers, she said.

Calves subject to these methods were often found to have suffered cranium haemorrhages or skeletal damage.

Even where calves survived, the time to standing and taking first colostrum from the dam – central to developing disease immunity – was often prolonged. Calves could be affected throughout their lifetime, she warned.

More emphasis on managing heifers and cows to parturition was needed.

“Calving ease has a relatively low heritability, but selection against dystocia is possible.”

Post-calving care needed to include protecting the newborn from extreme temperature, ensuring adequate intake of colostrum and ensuring a good cow/calf relationship was developed, she advocated.