During last season, many producers had serious issues with low milk solids, particularly milk protein. With average milk fat & protein figures around 0.2-0.3% lower than normal seasonal averages, this may mean losses of income in excess of $60,000 for the average western Victorian dairy producer. Given this, last year gave producers a good chance to investigate what really makes differences in milk solids when feeding concentrates.
With milk protein being the highest valued portion of milk, most producers worked to manipulate feeds such that protein percentage or volume lifted (it is important to distinguish between the two as many high producing cows will have lower percentages and still provide higher income due to their volume). The strategy for manipulating milk protein is to increase starch levels in the feed and increase microbial protein flow from the rumen.
Most producers will know the protein comes in many forms and that all forms are not equal. Energy is no different. Energy may be supplied as starch, fat or sugars and is also found in other components of the diet. Increasing starch level will increase the overall glucose supplied to the system and this is what drives milk protein production. It is important to deliver this as starch because other forms of energy (eg fat) actually suppress production through the oversupply of PUFAs (poly unsaturated fatty acids). Many concentrates supplied in the market utilize feed ingredients which contain high levels of fat, while starch is best supplied in cereal grains such as wheat and barley. These PUFAs have also been connected to poor fertility, weight loss and poor feed conversion.
Increasing microbial protein flow is achieved via manipulation of the types of protein supplied, the amount and type of fibre supplied and the overall level of feeding. In general terms however, when supplying a properly balanced diet with a concentrate formulated specifically for the herds individual requirement which matches the forages and fodder available, rumen function should be optimized and microbial protein flow will be sufficient.
For the best results, producers need to know not only the energy and protein levels in their diets, but also know the types of energy and protein they are supplying as this can have major influence on the cow’s ability to produce milk of the best quality. Speak to a consultant, your nutritionist or Reid Stockfeeds to gain a better understanding of how to manipulate milk solids production ahead of this coming season.