Milk Production
Dairy farming is not an easy venture. Dairy cows are complex animals that are pushed to their physiological limits, so it is crucial to get management and nutrition right at all stages of life if good levels of production are to be achieved. At Vital Animal Health, we understand that all stages of the life cycle of a dairy cow must be attended to and managed properly in order to get good results. Too often, the milking cow is the only animal on the farm that is considered to be productive. However, we mustn’t forget that calves, heifers and dry cows all have their own parts to play in the farming system.
Calves need to have adequate nutrition and mineralisation in order to build a strong immune system and achieve good growth rates (which plays an important role in breeding and early entry into the milking herd).
Heifers are required to conceive a calf and at the same time need to maintain decent growth rates in order to calve down at a good body size.
Dry cows are resting and recovering in preparation for the next lactation and are also growing the next generation of calves.
It is by paying attention to every animal on the farm that you can realise the potential that the genetics of these animals carries. The products that we manufacture or distribute are all chosen to help farmers attain the best performance during these different stages.
Dry matter intake and its effect on the cow
The main objective in feeding management for lactating cows is to increase their dry matter intake. With this increase should come higher levels of milk production. Fodder quality is a major determinant of dry matter intake as well as rumen function. Typically quantities of very poor quality forage are fed to smallholder dairy cows, with a heavy reliance upon supplementing such nutrient-poor fodder with compounded feeds. The poor quality of the forage compromises rumen function but also reduces DMI because of poor palatability, and high fibre content. An often quoted rule of thumb is that an increase of 1% in grass digestibility will increase dry matter intake by 0.3-0.4kg DM and milk yield by 0.25 litres. By improving the fodder content of the diet with a regular, reliable inclusion of good quality digestible fibre we improve both rumen function and intake and consequently improve milk production. An added benefit of this is that a better functioning rumen will also be able to extract more from the remainder of the diet, even if the quality of that portion is still relatively poor.
Feed the Rumen, Feed the Cow
A well functioning rumen is a factory producing energy and protein for the cow from a relatively poor food source. Raw materials (plant material, water etc) are ingested. These provide a surface on which microbes can collect and are also the food for them. In a process of regurgitation and chewing, the material is ground up to make more surface area and break open the material to allow microbes better access. They grow and reproduce and the population increases. In order to make more of themselves they build cell walls out of protein and release carbohydrates (fatty acids). These two things are absorbed and digested by the cow to supply much of their energy and protein needs. The rumen is therefore the home the microbes are given by the cow to live in and proliferate. The rest of the cow's gut is devoted to digesting these microbes and the other nutrients that come through in the diet.
All fodders are equal, but some are more equal than others
Fodder quality can be looked at in two ways. First is the nutritional content of the fodder itself, second is how much of that fodder a cow will eat. The greatest single cause of low-quality forage is harvesting hay or silage when it is too mature. On many dairy farms, as much as half the grain that must be fed is due to the failure to harvest forage at an early growth stage when it is higher in energy and protein and has lower fiber content.
Fodder quality - composition
As a plant grows, its nutrient composition changes in different parts of the plant depending upon its age and the function of the part. In a grass, the plant is full of nutrients when young as it needs these to grow. As it ages however it then starts to sequester nutrients to other jobs - it stops growing, and stores energy and protein for instance in a seed that it will need when it tries to grow once it has dispersed. It also requires more structural support as it gets bigger, so whilst cellulose is used in softer, quickly growing parts it has to use a stronger material, lignin, to give it more and more stiffness and strength as it gets bigger. The nutrient quality of the forage therefore declines with age with an increase in lignin compared to cellulose and a loss of nutrients to other parts of the plant.
Fodder quality - harvesting
How the fodder is harvested also affects the quality. If the forage is grown for bulk (farmers pay per kg) then it is allowed to get bigger (and older) before harvesting and therefore has lost some of its nutrients to flowering or seeding etc. The softer parts (ie with more cellulose than lignin) can also be broken more easily, so careless harvesting can damage the softer parts which are lost, leaving only lignified stems to be baled.
Fodder quality - palatability
As fodder grows, ages and requires more structural support it gets more "woody". The "woodiness" comes from the plant reinforcing cells with a much stronger structural carbohydrate, lignin. This is measured as the fibre level in a plant in a couple of different tests. One is with "neutral" detergent, rather than "acid" detergent. The Neutral Detergent Fibre measurement indicates how "woody" the plant is and the higher the NDF, the higher the woodiness and the lower the amount eaten by a cow.
Mineral nutrition and milk production
There is an essential need for minerals, especially in high performance stock. Minerals are required for better growth, better yields and better feed efficiency and need to be supplemented with a good quality, well formulated supplement. In Kenya, most dairy farmers are running zero-grazing or semi-zero- grazing systems, which is a good option in areas of land limitations as it maximises the use of available land. The majority of dairy cows are Holstein-Friesian, with a relatively small number of Jersey and Ayrshire. Cows are fed a variety of forages, depending on availability and location, including napier grass, maize, corn silage and Boma Rhodes grass. A big problem for East African ruminants is caused by the high iron content of the forage; East African soil contains high levels of iron, which then results in high levels in the forage. This is often over twice the requirement of the animal, which is not a problem in itself but iron acts as an antagonist to copper absorption, reducing the amount of copper available to the cow and inducing secondary copper deficiency. Because of its prevalence in Kenya it presents a severe challenge to performance in all life stages and can be used as a model for how mineral deficiencies can have huge impacts even though relatively small amounts are required in the diet.
Copper is essential for energy metabolism, and without sufficient levels in the body animals cannot utilise the energy from their feed for metabolic processes. This, in turn, has a negative effect on growth, production and reproduction. As copper is also required for the maintenance of coat colour and condition, an obvious indication of copper deficiency is the gradual change of the coat from black to brown, together with an unkempt, dry coat. This problem with secondary copper deficiency is extremely common in Kenya due to the high levels of iron in the forages. All Vital mineral formulations apart from Vital Kondoo contain at least three different sources of copper to combat the problem of copper lock-up and it is also for this reason that none of the Vital minerals contain any intentionally added iron or molybdenum. Copper is not the only mineral supplemented in the Vital range. Typically formulations contain salt (NaCl), phosphorous, calcium, magnesium, selenium, manganese, zinc, iodine, copper and vitamin B12 as deficiencies of these minerals have a devastating effect on animal performance.