To ensure calves grow to become healthy, productive members of the future herd, they need to have the best possible start in life.
We talk to Co-op Veterinary Programme Manager Mike Shallcrass, NZAgbiz National Sales and Marketing Manager Carla Rawson, and SealesWinslow’s Nutrition Extension Specialist Simon Butler about setting your calves up for success.
One of the biggest impacts on calf rearing profitability is disease, so the more you can do on-farm to prevent disease, the better your rearing operation will be. Mike suggests using the dry period to get your sheds set up well and make sure you have chosen good calving paddocks.
“It’s really important that steps are taken to prevent disease from getting into the shed in the first place, to make sure the calves are as healthy as possible, so they can resist disease. If it does get in, you need to prevent it from spreading between different pens,” he says.
Colostrum is an essential component of building a calf’s immunity. When it comes to colostrum, the three Qs are key: quantity, quality and quickly.
“The sooner you can get colostrum into your calves, the better. We suggest farmers collect gold colostrum, which is your first milking colostrum. Test it with a Brix refractometer to ensure it’s greater than 22% Brix. If it’s not, we suggest you find your next best colostrum and fortify it with a product like Jumpstart™ to get those higher immunoglobulin (IgG) or Brix levels that the calves need,” Carla says.
“The calf’s ability to absorb those antibodies drops very quickly, so ideally, pick up the calves twice daily and feed them two litres of colostrum in their first 12 hours, and another two litres within the next 12 hours.”
Mike says the only way to accurately ensure calves have received enough antibodies (“successful transfer of immunity”) is to blood test. A 2015 study of more than 3,800 calves across 107 farms found that a third had failure of passive transfer1.
“Calves that don’t get enough colostrum are twice as likely to die during the rearing period than calves that have a successful transfer of immunity. It’s a good idea to talk to your vet and get some blood samples taken from a selection of calves to check that your system is working and that you are getting enough colostrum to your calves,” Mike says.
It is important to understand the different types of proteins and fats that are found in calf milk replacer.
“A whole milk powder-based product is as close as you get to whole milk that you get from a cow in terms of the protein composition – 80% casein and 20% whey. The casein component is the important part, as it curds in the abomasum and slowly releases the nutrition back to the calf throughout the day,” says Carla.
“The whey component goes through into the small intestine, increasing the transit rate – the higher the whey content, the faster it passes through the calf, which can cause scouring and slow growth rates. You want the calves to get to their growth targets as quickly as you can, and that’s what you’ll get with a whole milk powder-based product, like Ancalf.”
The role of a calf meal is to bridge the gap between a milk-fed calf when its rumen is still developing, and a grown calf that can ferment plant forages for growth and reproductive development. Simon says that when a calf suckles on its mother’s teat or the feeder teat, the suckling stimulates the oesophageal groove, transporting milk directly into the abomasum, bypassing the rumen.
“Early hard feed intake is key because that feed and the water that the calf is drinking provide the substrates and the initial microbial population that fermentation requires to begin. The fermentable carbohydrates, starches and sugars in the meal are converted into fatty acids, which are essential for rumen development and growth throughout weaning and beyond,” says Simon.
“You can have a calf meal that may have similar metabolisable energy and protein levels, but if the fat exceeds 4% it can inhibit rumen function. A calf meal needs to be palatable to drive those early hard feed intakes, but it needs to be made of the right stuff; protein sources that are not only highly digestible, but provide a suitable suite of amino acids that the calf requires.”
Mike says advance planning is crucial for successful calf rearing.
“Your calves are the future of your herd, and you’ve got one shot to set them up. So you must plan what you’re going to do to make sure they have every chance of successful rearing and entering the herd. Make sure those calves are getting enough good-quality colostrum within that first 12 to 24 hours of life. You want them to be set up well for weaning and to be able to continue to grow really well after you’ve stopped feeding them milk, which means getting hard feed and water into them to drive rumen development.”
1 Cuttance et al. 2017. “Prevalence and calf-level risk factors for failure of passive transfer in dairy calves in New Zealand” in NZ Vet Journal. 2017 Nov; 65(6):297-304.
