Lactating Cows

By this point we have reared our calves well, feeding Vital Ndama to support their needs. We ensured our heifers have grown well using Vital Joto to meet their mineral requirements and they have been served at 55-60% of breed weight. We have managed our pregnant cow well including feeding Vital Dry in the last eight weeks of pregnancy to prepare her physiologically for the demands of lactation. We have a healthy, good sized animal ready to enter the lactating herd. Within 4-5 days of expected calving we have switched her mineralisation to Vital Maziwa to start supplying good levels of phosphorus, calcium and other minerals required in her role as a lactating cow.

Nutrition in a lactating cow is critical. The energy requirements of lactation are huge and almost double the nutritional needs of a non-lactating cow. Providing a complete and balanced diet can prevent and alleviate many common health problems and is essential if optimal production is to be achieved on the farm. There are many resources available detailing the optimum management of a lactating dairy cow but generally these are at a level beyond the capacity of smallholders to understand how to implement under the conditions imposed by their type of production system. Discussing which amino acids are limiting and how to calculate TDN values does not help a smallholder who is struggling to see production from his cows although he is feeding a commercial compound feed and some green chop and dry grass to his animals. In desperation other feeds are added from poultry waste to fermented pineapple to banana stems in order to try to get the cows to perform with increasingly negative effects. Our belief is that if we can teach a basic understanding of rumen function and the fundamental importance of fodder then significant gains will be made on the farm by utilising the biological potential of the cow herself.

We are also passionate about making sure that the other life stages of the cow are not forgotten. We will only reach this point if we have reared our calves well, feeding starter, water, good fodder and quality minerals to support their needs. We will have to ensure that our heifers have grown well and they have been served at 55-60% of breed weight. We will have to have managed our pregnant cow well, particularly by attending to her feeding and understanding the role calcium, magnesium and other minerals play in predisposing to the devastating effects of milk fever. We will have restricted calcium and potassium rich forages and will have fed a low calcium supplement such as Vital Dry in the last eight weeks of pregnancy to prepare her physiologically for the demands of lactation. Only after all of this will we have a healthy, good sized animal ready to enter the lactating herd.

The basic components of any animal diet are water, energy, protein, and minerals, which make up the nutrient pool that satisfies the animal’s needs. If any of these are inadequate or missing, the others cannot be utilised properly and malnutrition results. Whilst we can provide energy and protein in the fodder and rely on rumen function to produce these components for the cow to digest we need to recognise that minerals play a pivotal role in animal nutrition, especially animals with such high nutritional demands as lactating dairy cows.

Minerals are inorganic elements that are required in small or very small quantities in the diet. They are found in all tissues of the body and normal growth, breeding and production depend on a regular supply. Many minerals interact with others, so mineral balance is often very important; other minerals are interdependent, such as sodium and potassium. Livestock need minerals for every aspect of growth and production. All body functions require a continual supply of all nutrients. Rumen bacteria need minerals to grow and cannot utilise the diet efficiently without them. Milking cows lose massive amounts of minerals through the milk, and this needs to be replaced if the cow is to continue as a healthy, high producer. High performance livestock have a greater demand for nutrients, due to better growth rates and higher yields. Supplementation with a carefully formulated mineral product such as Vital Maziwa is necessary in production animals; forages are a very poor source, and cereal and protein crops are also low in minerals. Forages can also contain high levels of mineral antagonists, which will decrease the availability to the animal of the small amount that is present.

The effects of mineral deficiencies include: decreased performance – lower yield, poor growth, decreased fertility; increased susceptibility to invasive disease – the immune system will not function effectively if minerals are not adequate, and wound healing is impaired, creating access for infectious pathogens; decreased feed efficiency – this leads to ill thrift and wasting and inefficient use of a major production cost component and an increased incidence of metabolic diseases such as milk fever, mastitis, metritis, ketosis, etc.

It should be noted that mineral deficiencies do not always cause visible clinical signs. Deficiencies tend to be progressive, which means they can be present for a while before overt signs are seen. So an animal that looks normal and healthy can still be struggling to thrive or have a lower milk yield than expected because of a lack of a certain mineral. In a lactating cow mineral deficiencies can have devastating effects. Copper deficiency can severely impair the energy metabolism of the cow and this will have a direct impact on milk production as well as affecting other systems such as immunity. Zinc is used in many aspects of the cow’s body; it works in the immune system for disease resistance and wound healing, in growth and development for healthy skin, udder and hooves, and within the animal’s general metabolism. Typical signs of zinc deficiency include dandruff, ringworm, lameness, reduced immunity and teat dripping.