Cows require quality feeding to sustain increased milk production. Adequate quantity of high quality forage with supplementary concentrates is necessary for cows producing over 10 litres each time of milking.
A good feeding strategy guarantees maximum use of available forage by allowing the cows to graze it or harvesting and conserving it at the prime stage of growth when it is most nutritious and before it becomes highly fibrous, therefore, of low nutritive value.
Yet, harvesting and conserving the forage in form of silage or hay is still a major challenge for most farmers, the main constraint being lack of technical know-how and proper equipment. This notwithstanding, all dairy farmers are encouraged to grow forage to reduce the cost of milk production.
A mature dairy cow in mid-lactation (four to six months after calving) consumes approximately 5 per cent of its body weight in terms of dry matter.
However, with the exception of hay that has over 80 per cent dry matter, most of the available green forage, including pasture and conserved forage such as silage contains about 20 to 30 per cent dry matter.
The farmer needs to do some calculation to know the actual quantity of fresh forage that the cow needs to be given. For example, a dairy cow with approximately 500kg live weight requires about 25kg dry matter per day, which comes to about 80kg to 100kg of fresh feeds depending on the actual moisture content.
If the cow has an average milk yield of between 12kg and 15kg per day and the available forage is of reasonably high quality such as grass or fodder together with legumes like lucerne or desmodium, then this feed may just be adequate even without supplementation with concentrates.
However, if the yield is higher, then supplementation with concentrates will be necessary at a rate of 1kg dairy meal for every three litres of milk.
Adequate high quality forage
For a cow in early lactation, that is one to three months after calving, extra care is required in feeding because such cows tend to have low appetite, yet the body’s nutrient requirement is too high to cater for both lactation and recovery from the effects of pregnancy.
Quick recovery is essential if the cow is to resume oestrous early in preparation for the next calving.
The farmer is advised to ensure that the cow gets adequate quantities of high quality forage. The concentrates should be made available, but not more than 40 per cent of the total ration.
The inclusion of roughage is crucial as it ensures that the cow’s rumen functions optimally to avoid incidents of lactic acidosis and depressed butter fat content.
Another critical stage for a dairy cow is in the late gestation period, about four to six weeks before calving.
During the period, the cow’s feeding capacity is limited due to the developing foetus and associated tissues such as placenta taking up much of the abdominal space at the expense of the rumen.
As a result, the heavily pregnant cow needs feeds with concentrates through a regime referred to as steaming up. This helps to prepare a dairy cow for dropping a heavy calf and builds reserves that will support high lactation in early during the early post-delivery period.
Remember to always ensure that all dairy cows, whether in milk or not, have access to complete mineral supplement and plenty of cool and clean drinking water at all times irrespective of the production system.
Access to minerals ensures metabolic disorders such as milk fever are avoided, while making plenty of water available to cows is a sure way of sustaining high yield, given that milk is approximately 88 per cent water in composition.
Dr P. K. Migwi, Animal Science Department, Egerton University