Rearing replacement calves is possible in so many ways — no system is right.
It just has to be one you are happy with, produces good results without excessive losses, and doesn’t take up too much of your precious time.
A system I have helped farmers set up since the early 1990s is the ‘‘once-a-day fortified milk – early rumen development system’’ originally documented by Tom Grant from Corowa.
It is important to realise that this is a ‘‘system’’ with many components, and all the parts must be adhered to or — like all rearing systems — it may not produce the desired outcome.
In my experience it is one of the most successful and simplistic calf-rearing systems to establish.
Once-a-day fortified milk — early rumen development system:
Calf rearing is about turning a milk-digesting (largely monogastric) animal into a ruminant.
A researcher, Tom Grant, developed a system using fortified (high strength) milk by adding powder to waste cows’ milk.
This increased the energy content to the point where young calves could be delivered their entire energy requirement in a single small-volume daily feed.
The theory was simple — calves fed once a day become hungry, so they would start eating solids at an earlier age and this would promote early rumen development.
There is plenty of science to support this concept, including recent work by Dr Gemma Chuck when studying her PhD at The Vet Group, showing what growth rates are possible using fortified milk.
But what does it mean in practical terms for farmers trying to set up the most efficient rearing system on their farms?
As a veterinarian with a post-graduate degree in ruminant nutrition I have used the system to assist many farmers to simplify their calf-rearing system. In some cases, we have used it to overcome health and nutritional problems but it also works incredibly well in healthy calves.
Best of all, when it is all put together it can result in massive labour savings for your farm.
So, how does it work?
Calves reared to enable rapid early-rumen development are receiving substantial nutrition across the rumen wall (from rumen fermentation) by two to three weeks of age so that if they receive a setback from some the common small intestinal diseases at this age (viruses, bacteria or protozoa) they are not 100 per cent reliant on milk for their nutrition.
Thus, they are more likely to be able to cope with short term gastrointestinal tract (GIT) damage and continue to grow at a constant rate during the conversion from milk to solid food reliance.
Calves reared using fortified milk early rumen development systems can be completely weaned from milk by five to six weeks of age.
This system works; I have helped many farmers to establish this as the only rearing system on their farm during the past 25 years and very few have chosen to return to their conventional system when they see the labour saving (of once-a-day feeding), the simplicity and most importantly the ability to successfully rear healthy calves on their farm.
■For more information, phone Mark Moylan from Total Stockfeeds on 0472 835 585.
—Dr David Colson
The Vet Group