Preparation for calving & lactation

These critical periods need to be well managed in the dairy cow so that problems are minimised and production optimised.

The success of an event is as good as the preparation that goes into it. In this case, the event is the production of 9 000kg of milk over a 300-day lactation period. In the process, the cow will produce 430kg lactose (milk sugar), 300kg protein and 270kg butterfat. This requires the removal of 480kg of glucose, 300kg of amino acids and 300kg of fatty acids from the cow’s bloodstream during the lactation period.

Approximately 3,6ml of blood would need to pass through the udder in this process. The dairyman will have to ensure an intake of at least 2,43t concentrate and 5,67t good quality fodder on a dry matter basis over this period. Talk about running the Comrades Marathon, every day, for 300 days on end! Preparation for this phenomenal performance comes down to catering for the change in physiology of a dry pregnant cow to that of a high producing lactating cow.

Recognise the potential danger of metabolic related health dilemmas such as difficult calving, retained afterbirth, displaced abomasum, milk fever and acidosis. Physiological changes the dairyman must cater for include the secretion of oestrogen for the growth of the udder’s duct system and, with progesterone, for the development of the milk secreting portion of the udder.
Microbes in the rumen will supply the necessary nutrients in the form of 44% protein, 40% soluble sugars and starches, 3% fat and 7% minerals to the lower gut to support this challenge.

Cows should be dried off in the condition in which they are to calve – a condition score of about 3,5. Recommendations for steam up include keeping calcium and potassium intakes down. My grandson once said, “You can’t fix anything unless you know how it works.” How right he was. 

Malcolm Stewart-Burger founded the Society of Master Dairymen and designed the Maxi Milk System. He is currently a part-time consultant to Nutex Feeds and De Heus. Contact Malcolm at [email protected]. Please state ‘Milking for profit’ in the subject line of your email.