ANIMAL NUTRITION
Maximising growth through rumen development
The drive to have calves double in birthweight in the first 60 days of life has been a standard goal for most. Meeting these liveweight targets is important and ensuring the calf has all they need to set them up for success is part and parcle of an effective rearing system. A developed rumen is fundamental to enable the calf to be able to effectively digest feed and forage and therefore, be able to meet key liveweight targets. So what is required to develop the rumen? When calves are born, their rumen is undeveloped. The good quality colostrum and milk that is fed to calves, bypasses the rumen and is diverted directly to the abomasum. It is the water, meal and roughage that aids in the growth and transformation of the rumen and the rumen papillae. The faster this growth occurs, the quicker calves can be weaned off milk and onto pasture. When done well, the calves can be weaned quickly and effectively, all whilst being able to reduce risk of a liveweight check at weaning, when removing milk from the diet. There are several aspects of rumen development that take place. Firstly, water is an essential component that can often be overlooked as how
it plays a part. Unlike milk which is diverted past the rumen, water goes directly into the rumen. Water acts as a carrier for the rumen microbes to multiply and break down the feed and forage. When water is restricted or unavaliable, the dry matter intake of feed drops, therefore reducing daily liveweight gains. Secondly is the development and growth of the rumen papillae. Papillae are long finger like protrusions that line the rumen, increasing the surface area. The longer and fatter the papillae, the more effiecently nutrients can be absorbed from the rumen. Components within the meal such as starches and sugars drive the growth of papillae. Ingredients such as maize, wheat and barley deliver the desired starch level. Optimal starch level of a starter meal is 35–42%, not only to drive the papillae but also to aid in supplying fermerntable carbohydrates as a quality energy source. When the papillae grow quickly, they can stick together. Quality roughage, such as hay or straw, brush through them seperating them to optimise the surface area. Without effective fibre, keratin can build up on the papilae, reducing the nutrient uptake, negatively impacting on nutrients being used for growth.
Short stalky fibre works best to scratch between the papillae distrubing the keratin layer and seperating the papillae. Finally, the development of the rumen muscle itself. A 500kg cow can have a rumen capacity of over 150-200 litre capacity when on a pasture based diet. Building this muscle as a young calf is essential. The rumen needs to be equipped to contract 1-3 times per minute, in order to move the digesta so that the micorbes can access all of the feed. Muscle development comes from a balanced diet of grain from meal and fibre. To ensure that liveweight targets are met, the development of the rumen is cruicial. A balanced calf meal such as Calf Max 20% Muesli, 20% Pellets and 16% Pellets provides a high level of starch to drive the papillae development and delivers fermentable carbohydrates as an effective energy source to optimise daily liveweight gains. For more information contact your local Ruralco or SealesWinslow Sales Representative today. THIS PROMOTIONAL FEATURE WAS PROVIDED BY SEALES WINSLOW
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