Managing transition dairy cows—treat those mothers right (Proceedings)
In the words of H.D. Hoard, "... this is the Home of Mothers. Treat each cow as a Mother should be treated." We need to take this thought to heart as we think about how we should treat the new moms and moms-to-be on our dairy farms. These cows are at great risk due to the great physiologic, metabolic, and management changes they go through in a relatively short time period. Due to these great changes our transition cows are placed in a state of negative energy balance leading to fat mobilization, as demonstrated by non-esterified fatty acids or NEFA's in the blood stream. If we cause excessive fat mobilization, the NEFA's will overwhelm the liver's metabolic ability leading to the development of ketosis and fatty liver. Cows suffering from fatty liver will have a reduced capacity to produce glucose needed for milk production and to metabolize protein, leading to suppressed immune systems and other problems. These fresh cow problems will lead to the development of other costly diseases in fresh cows such as metritis, displaced abomasums, and mastitis as well as increased culling rates. We need to look to see how we can pamper these cows with attention so they come through their transition period healthy and productive and ready to pay us back for our devotion to them. So how do accomplish this? Two areas to focus on are nutrition and transition cow environment / management.
The most important consideration in the area of the nutrition of transition dairy cows is to control the energy intake in our dry cows. A far off dry cow needs to only consume a little more than her maintenance energy requirements. According to the 2001 Dairy NRC recommendations a 1550 pound dairy cow would require approximately 14.5 Mcal/NEl per day. A recommendation by Dr. Jim Drackley is to feed a mature dry cow 90 to 110% of her energy requirement or approximately 13-16 Mcal/NEl/day. If a cow consumed 27 pounds of dry matter a day the diet she consumed would only need to be an energy density of .60 Mcal/NEl/# of dry matter. This realization has lead to the development of high forage (straw), low-energy diets for dry cows. The advantage of these diets is to increase rumen fill around the time of calving and to decrease the energy intake of the cows during the dry period. By not consuming excess energy for the duration of the dry period these cows do not become over-conditioned and more insulin resistant, two key factors for the development of excessive mobilization of NEFA's and fatty liver disease. For these diets to be successful the straw must be processed to less than 2 inches in length to prevent sorting. Water may also be added to these diets to improve palatability. New information may indicate that we can increase the energy density of our close-up cow diets without causing harm, but would indicate that the far-off diet energy density still needs to be low (~0.60 Mcal/NEl/#DM) for this scheme to be successful. This may explain the benefit seen by some when a low-energy diet is used for a one-group dry cow ration and points to the importance of our far-off dry cow diets.Dietary protein levels are also important for the success of our transition cows. Underfeeding protein may lead to suppressed immune systems and the decreased availability of carrier proteins needed for efficient metabolism. Current recommendations are to provide 1100 to 1200 grams of metabolizable protein/cow/day to our dry cows.
Finally a number of additives may be used in our dry cow rations to help make the transition period smoother. Rumensin aids in energy balance and feed efficiency and is strongly recommended by most research to aid in decreasing the incidence of energy-related metabolic diseases. Both rumen-protected choline and rumen-protected niacin have been demonstrated to reduce the development of fatty liver and ketosis and should be considered for dry cow diets, especially if a pre-fresh diet is available or if a group of heavier, at-risk cows exists in your upcoming calvings.
While these are some basic recommendations, your nutritionist will have a solid understanding of these concepts. Work with them closely to develop a plan that works for your cows.