Birth to weaning feeding guidelines
When it comes to preparing for the calf rearing season, it is easy to be bamboozled by a bevy of products, services and programmes. Let’s take a moment to step back, look at the bigger picture and touch on the fundamentals of nutrition after colostrum from birth to weaning.
Phase one – Intensive liquid feeding
In the first three to four weeks of a calf’s life, the objective is to optimise growth rate. The most effective feed to do that, especially in the cold spring, is milk and/or calf milk replacer. To meet the nutrient requirements, liquid feed can be fed at 17 to 20 percent of birth body weight. For example, a calf born at 35 kg (keep a set of bathroom scales handy at the shed to measure birth weights) requires 6 to 7 litres per day. Very young calves can only handle that level of feeding either free choice or over two feeds per day. During phase one, it is important to provide 20 percent Crude Protein (CP) calf starter free choice. Calves may not eat very much to start, but the sooner they are exposed to the hard feed, the better.
Phase two – Rumen development
If high rates of liquid feed continue, the calves would look fantastic, with glossy coats and strong weight gains, but milk or milk replacer does not promote rumen development. The starches and proteins in 20 percent CP calf starter do that. In phase two, the liquid feed can be dropped down to 10 percent of birth body weight, or one feed of 3.5 litres per day for a calf born at 35 kg. This in turn helps stimulate intake of the calf starter. As these animals are growing and maturing, they become ready to be exposed to some long stem forage to help develop rumen musculature in phase two. To optimise nutrient density, good quality lucerne hay and/or pasture can be offered. A note of caution though,too much yummy pasture may limit the intake of the calf starter and negatively affect rumen development and growth.
Phase three – Weaning off milk
Weaning off milk is recommended when the calves are consuming at least 1 kg of 20 percent CP starter for three days in a row. At this level of intake of 20 percent CP starter, there are enough nutrients to keep the calf growing even when the nutrients from milk are no longer entering her system. In addition to the calf starter, the calves need free choice access to the best quality pasture available.
It is important to note that free choice access to clean, fresh, palatable water is critical through all three phases. The reality is that the more water a calf drinks, the more she eats and the more she grows.