More Discipline approach needed to get best from calves

Dairy farmers would benefit from taking a more measured approach to calf rearing according to Rob Warrington, National Calf Specialist with NWF Agriculture.

"On many farms, calf rearing is seen very much a secondary enterprise but this attitude needs to change," Mr Warrington observes. "Farmers need to assess their approach and focus on the fact that what they are rearing is not a calf, but a replacement heifer which has a potential value of £1500.

"The calf stage is the first vitally important step on the journey to produce a valuable animal and how the first few weeks are managed can significantly affect the entire growth period. To maximise the benefit of the calf stage farmers must be prepared to take a more measured approach to calf management."

Mr Warrington believes few farmers really understand the impact on the first 12 weeks of life on heifer growth and questions how many farmers actually measure how fast calves are growing.
"Dairy farmers will typically say they aim to calve heifers down at two years but the reality is that most heifers calve at closer to 27 months. Part of the failure to hit calving age targets is sub-optimal growth rates in the first 12 weeks of life."

NWF have recently begun using a system developed in Holland which involves using a weigh band to measure calf chest girth as a way to assess calf weights and growth rates and Mr Warrington believes the approach will soon become widespread.

"To achieve sufficient size to calve down at 24 months, a calf needs to weigh 100kg at 12 weeks old. From birth to weaning calves need to grow at an average of 4kg per week. When weaned at around 49 days old she must already weigh 69kg and be able to maintain a growth rate of 5kg per week.

"Unless calves are being measured and weighed it is quite easy for them to fall unnoticed below the target growth curve, leading to potential problems."

Mr Warrington advises farmers to make sure the management protocol they follow is geared up to produce the target growth rates. After three days on colostrum he recommends calves receive two litres of milk replacer twice a day for 10 days building up to three litres twice a day.

"One of the hidden benefits of the higher milk price is that more calves are being fed on replacer and fewer are getting waste milk. Young calves need a diet rich in nutrients and capable of supporting high growth rates. It must also be disease free.

"There is considerable research to show that raw waste milk fails on both counts and that milk replacer is a considerably more cost effective feed for calves. Feeding waste milk to calves greatly increases the risk of infection leading to poorer performance in later life."

Mr Warrington believes that many farmers would benefit from moving to automatic calf feeders. As well as ensure a consistent supply of milk and freeing up labour for other tasks, the feeders can provide valuable management information, helping to spot calves that aren't feeding etc.

While calves are on milk it is also essential that the rumen is being developed to allow it to effectively digest forages post-weaning. Mr Warrington points out that the rumen villi must be well developed before weaning if a growth check at weaning is to be avoided.

"Many calves are just not fully prepared for weaning. As such, when milk supply is stopped they are not able to effectively digest the new diet, leading to a deficit in nutrient supply and a fall in growth rate.

"When you are expecting a calf to grow at 5kg per week you can't afford a check in growth as the calf will struggle to make it up. It is not unusual for calves to suffer a growth check of equivalent to two weeks growth, around 10kg, when the rumen is not properly developed."

The key to effective rumen development in calves is the early inclusion of forage in the diet and trials in Holland have shown better growth rates where high fibre levels are included in a palatable concentrate. Where calves were fed pellets containing lucerne and other quality fibre sources to achieve a minimum 14.5% NDF, the rumen villi developed more rapidly and a more stable rumen microflora was established than where long fibre was the only source available.

"Feeding high fibre concentrates has a number of practical advantages. As well as being quicker and easier to feed than silage or hay, there will be less dust and waste and it is far easier to check calves are eating what they should.

"With heifers in short supply and no real sign of an upturn in numbers, prices will remain high. Getting calves off to the best possible start should be a priority with routine measurement a valuable management approach," Mr Warrington concludes.