What’s happening to dairy calves at grass?

“A number of dairy calves are displaying wasting symptoms post weaning and after turnout; many of the calves affected are dying.”

These were the opening words from Donal Murphy – of Sliabh Luachra Veterinary Centre Co. Kerry and XLVets Skillnet – when he addressed an audience at a veterinary workshop earlier this month in the Horse and Jockey Hotel.

A survey carried out by XLVets identified 35 cases involving young dairy calves that failed to thrive after turnout to grass post weaning and displayed wasting symptoms.

In addition, many affected calves died as a result of the condition and Donal highlighted that the source of the problem was unknown. It was also noted that the condition is affecting calves throughout the country and – naturally – there is a high concentration of cases in dairying areas.

Sharing their experiences and possible solutions to the problem, speakers from Regional Veterinary Laboratories (RVL), University College Dublin (UCD) Veterinary School, Teagasc, XLVets and the ruminant nutrition sector also attended the event.

Finbar Mulligan – UCD Veterinary School – outlined that the rumen development of young calves could be thwarted by the over consumption of young grass, with high levels of sugars and protein.

Athlone RVL – Seamus Fagan – emphasised the weaning process as a major event in a young calf’s life.

He said: “An optimum level of fibre in the diet through this transition [and that] high-quality lush grass may not be the best food for supporting rumen development.”

Teagasc’s Emer Kennedy added that sudden weaning at a young age places much more stress on calves than a gradual and planned approach.

Kieran O’Mahony – of Glen Vets in Tipperary and XLVets – stressed that it is important to re-evaluate how calves are managed from before weaning to the end of the initial 12 weeks of grazing.

Virginia

“After that planning and managing a calf-friendly transition from milk to grass that supports rumen development is key,” he added.

To conclude the event, Donal highlighted: “The main objective in calf rearing is to develop the rumen, so that the animal is capable of being an efficient converter of forage into growth and productivity.

“We have learned that early-rumen development can be influenced by a multitude of factors including adequate intake of colostrum and milk or milk replacer – feeding neither too much nor too little.”

Water quality, the palatability of concentrate feed, grass type and grass quality are also important factors, he explained.