NZ Dairy Autumn 2022

80 | nzdairy DAIRY SERVICES » AgriVantage Finding the right milk replacer a challenge Russell Fredric AgriVantage consultant nutritionist Natalie Chrystal acknowledges finding the right milk replacer can be a challenge. However, selecting a well-balanced, quality product will help support increased lifetime productivity, and the cost effectiveness of a milk replacer should be seen in this context, she says. “Research and practical experience have shown that improved pre-weaning nutrition and early development of young animals positively impacts lifetime performance. “For dairy heifers this means increasing lifetime milk production, but with so many milk replacer options available, choosing a product which will help you achieve your rearing goals can sometimes be very difficult.” One of the biggest misconceptions Natalie encounters is the belief that whey-based milk replacers are not as good as those that are casein-based. “There’s probably more variation in quality within casein-based milk replacers or within whey-based milk replacers than there is between the two different types of products. There’s so much more that goes into producing a milk replacer that will support increased productivity than whether it’s casein or whey-based. “A real misconception is the assumption that milk that’s fed to calves must curd for it to be properly digested. “While that is true for casein-based products, whey-based milk replacers don’t curd and they don’t curd because they don’t contain casein proteins. That’s not to say that there isn’t sufficient high-quality protein in them or that they don’t provide sufficient nutrition for a young animal.” Regardless of milk replacer type, Natalie recommends rearers select one replacer with a balanced amino acid profile to support early tissue development. It should also contain a readily digestible fat source to ensure young animals have enough energy for early growth and include added vitamins and minerals. The osmolality of a milk replacer is also an important factor in optimising the performance of young animals. Proteins play an important role in many bodily functions, including formation of muscle tissues and the production of hormones. Each of these proteins are made from a different combination of amino acids, the individual building blocks of protein. “It’s important to provide a balance of those amino acids. Having a whole lot of one amino acid is not useful if you do not have enough of the others. “Not only is this expensive, but it contributes to nitrogen loading and can lead to elevated ammonia levels in the shed.” Fat, one of the more expensive components in a milk replacer, is typically declared on the bag (for example 20% fat), which makes it is easy to compare milk replacers based on fat content. Unfortunately, it is much more difficult to assess fat quality and digestibility. “Always choose a milk replacer that contains highly digestible fat sources, like milk fat, palm fat and coconut oil. High quality milk replacers often contain more than one high quality fat source to help provide all the essential fatty acids required by the young calf.” Homogenisation of fat also helps to increase fat digestibility, as the very small particles are more easily absorbed from the digestive tract. The balance of macro minerals and lactose relative to other nutrients should be such that the concentration of dissolved particles in solution, or osmolality, of the calf milk replacer is close to that of cow’s milk. Too high or too low an osmolality can affect digestibility and can increase the risk of nutritional scours. Osmolality is hard to measure on farm, but typically milk replacers with high ash and lactose will have a higher osmolality. AgriVantage supply a range of quality Sprayfo calf, lamb and kid milk replacers, a colostrum Animal Nutritionist Natalie Chrystal is an authority in nutrition for all animal types. She has worked in the animal feed and nutrition industry since 2001 – in Africa, Europe, New Zealand and the South Pacific. powder and other proven products for rearing strong and healthy animals. Sprayfo milk replacers are made with unique spray-dry technology which dramatically reduce the size of fat molecules then encapsulate these with protein. Not only does this help to make the milk replacer highly digestible and highly soluble, but it also helps to ensure that these tiny molecules stay in suspen- 021 519 507 or 09 283 3425 Call us today! $249-$299 incl gst/courier 12 month warranty 25L and 30L available The Best Test Buckets in the Market! Portable Milking &Test Bucket Specialists