NUTRITION IN DAIRY ANIMALS

TARGETED NUTRITION — WITHOUT EXCESS FOR PEAK PERFORMANCE

BY JIMMY PARKER

Over the past few years there has been an increase in the number of on-farm or homestead dairy animals. Both the number of milk cows and dairy goats has grown across the state and the number of backyard/ home use dairies is growing. Nutrition is essential to success with these animals and can prevent a number of problems and bad experiences especially in small farms that might be new to livestock or have a bit less experience with dairy animals in general. While this is aimed at the homestead dairy producers, there should be some information that is relevant to beef cattle, meat goats or any other livestock production systems that require lactation.

Adequate nutrition is key to a successful lactation, and it starts well before the birth of the offspring that begins the lactation cycle. Feeding programs leading up to the birth of the calf or kid are essential to a good early lactation and that is key to total milk production throughout the cycle. This is true whether the plan is to be completely grassfed or geared toward a more traditional higher feed type production system.

Carbohydrates, amino acids (proteins), fatty acids (fats in general), minerals, vitamins and water are all required by the lactating animal to meet the demands of the mammary gland to produce milk and the basic milk components. Water is the most important nutrient in milk production and the most abundant nutrient in the milk itself. Fresh clean water is essential and often overlooked. A lack of water will limit the consumption of all the other nutrients and severely limit production. Vitamins and the correct mineral balance are also absolutely necessary but probably a bit too complex for an article of this length. There are great mineral and vitamin mixes that are readily available at your local Co-op and there is no need to reinvent the wheel here.

lactating animals, dairy or otherwise, will be using more energy than they take in early in the lactation. This makes having some stored body fat very important, with the note that too much stored fat can be problematic as well.

Fats are also critical. Fat in general is an issue in proper rumen function but a small percentage is critical. It is far more energy-dense than carbohydrates and adds a great amount of energy in small quantities. Fat is truly the fastest way to meet energy needs in theory, but rumen function limits the amount used. Fat will help with energy deficiencies but is rarely effective as the sole fix to poor-quality forages or limited grains. Levels of fat that are too high will coat forages and decrease fiber digestion, decrease feed intake, and effectively decrease both milk yield and the level of fat in the milk itself.

Protein is the most often discussed nutrient in animal feeds and it is one of the most critical nutrients in milk production. It is required for almost all body functions and plays a role in total milk production as well as milk fat and milk protein concentrations in the milk itself.

If your animals are too fat and not producing as much milk as you would like, then you can increase the protein intake and sometimes increase milk production.

Protein is made up of amino acids and the source of the feeds will determine which of those amino acids will limit total production. In corn- and soybean-based diets lysine and methionine are often the two amino acids that limit production. In grass-based diets histidine will likely limit milk production before lysine or methionine becomes a limiting factor.

Carbohydrates are the primary energy source for almost all animals. Ruminants such as cattle, sheep, goats and deer typically get a large amount of their carbohydrates from the digestion of fiber sources that humans cannot digest. Depending on the feeding systems and philosophy, grains and sugars can be a great source as well, though it is highly recommended that these be fed in smaller quantities multiple times each day to avoid digestive upset if they are added in substantial quantities. Excess carbohydrates, whether from grass or grain, will be stored within the animal as fat and having the correct amount of internal fat stored beforehand is critical to early lactation as energy needs tend to increase much faster than feed intake. Most all

Now for the commonsense portion of management. Always provide fresh clean water. This is especially important during the hot summer months. If your animals are too fat and not producing as much milk as you would like, then you can increase the protein intake and sometimes increase milk production. If the animals are too thin, you can reduce the protein levels and increase the calories by increasing carbohydrates or fats. While you will likely get less milk, you will improve body condition over time and help with rebreeding which can be a common issue in thin lactating animals. Keep in mind that as summer goes by, forage quality will decrease in most cases and supplementation may be required to maintain adequate production and body condition in the animals. Finally, pay attention to what you are feeding. Try to stay away from beef feeds, or meat animal feeds in general, as they often contain ingredients that are not labeled for dairy animals and could result in trace amounts of some medications reaching your milk tank if fed to your lactating animals.