Transition Cows Need Special Attention and Care
Dairy Pipeline: January 1998
Charles C. Stallings
Extension Dairy Scientist, Nutrition
Cows going from the dry period into lactation experience a great deal of stress. Most of the metabolic and infectious diseases occur during this time. A clean, dry, uncrowed environment is needed to minimize stress and prevent spread of contagious organisms. In order for this transition to be successful the rumen should be adapted to rations containing grains for at least two weeks before calving. Nutrient intake both pre- and post-calving should be maintained by using digestible rations that are palatable and nutritionally balanced. Many herds have gone to using a close-up or steam-up ration for cows within two weeks of expected calving. During this time both potassium and sodium intake should be controlled because excess can result in increased metabolic problems after calving. Avoid forages (grasses and legumes) that are high in potassium. Grass hays and pastures that have greater than 3% potassium should not be used as the primary feed for dry cows. Do not feed buffers (sodium bicarbonate or sesquicarbonate) to dry cows because they increase the sodium level. Some salt (sodium chloride) is acceptable because it supplies an anion (chloride) to offset the cation (sodium). Do not feed salt free choice, however. Anionic salts (calcium sulfate, ammonium chloride, ammonium sulfate, etc.) can be used in the close-up ration to create a metabolic acidosis that causes mobilization of bone calcium and maintenance of blood calcium after calving. Anionic salts should only be used if potassium in the ration is controlled. If high levels of potassium are present it is impossible because of palatability to add enough anionic salts to be effective. Vitamin E and selenium are needed during transition to maintain a strong immune system.