August 6, 2020
Donna M. Amaral-Phillips
University of Kentucky
Getting recently fresh dairy cows off to a sound, eventless start to this lactation pays dividends in improved milk production, reproductive performance, and profit. Research continues to show that management and feeding practices within the first 2 to 4 weeks after calving have a long-term positive or negative impact on not only milk production and health of cows throughout the lactation, but as importantly on fertility and early embryo survival. Throughout the year, one should review management and feeding programs for these cows to avoid compromising their performance, especially when larger numbers of cows are fresh than on the average. Areas to evaluate include the following:
Plan and Correct Housing When More Cows Are Calving
Minimize overcrowding, and added stress on recently fresh cows, especially the first 2 to 3 weeks after calving. Bunk (≥ 30 inches per cow, 1 headlock per cow) and resting (1 stall or >100 sq. ft/cow) space should not be limited so as to allow for maximum feed intake and time available for rest and rumination. Particular attention should be paid to providing adequate bunk and resting space when flushes of cows are calving, i.e. more cows calving for “base building” production programs.
Watch Body Condition in the Previous Lactation
Cows should freshen with a body condition score of 3.0, not 3.5 or higher. This target is thinner than many farmers identify in cows having adequate condition at dry off or freshening. To achieve this goal, cows must be fed adequate, but not excessive, amounts of energy during the previous late lactation and dry period. Cows with long days open the previous lactation are one reason for overconditioned dry cows.
Watch Body Condition Losses in Early Lactation
Feeding and management programs should be designed and implemented that minimize losses of body condition or weight during early lactation. Cows in a study that lost 8% of their body weight during the first 3 weeks of lactation had poorer quality embryos with less embryos being viable. Not all cows lose weight or body condition in the first 21 days after calving. In a Wisconsin study on two commercial dairies (a total of 1,887 Holstein cows), 42 % of the fresh cows lost body condition the first 21 days of lactation, but 36% of cows maintained body condition with the remaining 22% of cows gained body condition. Milk production across the groups was not different. Another study showed similar trends in the percentages of cows losing, maintaining or gaining body condition. The group that lost body condition had more health events and less cows pregnant after timed AI, again with no difference in milk production between the groups.
Target Expensive Additives to Fresh Cows
Fresh cows should be housed in a separate group of cows, when possible. This management practice allows one to target specific feeds and additives to this group of cows. For example, feeding ruminally protected choline during the close-up dry and fresh period increased milk production by an average of 3.5 lbs/day over 21 research studies.
Take Time to Observe Fresh Cows
At least daily, the behavior (i.e. rumination, eating feed) and overall health of recently fresh cows should be observed and corrective measures taken as needed. One should take time to observe these cows at a time(s) outside of those associated with milking practices and not to solely rely on the use of technology or other workers/family members to detect changes from normal behavior.
Keep Fresh Cows in a Clean Area
Fresh cows should not be housed with “sick” cows. A cow’s immune system is less responsive to disease challenges the first 10 days after calving. An increase in exposure to disease-causing agents (i.e. sick cows with mastitis) can increase the chances of disease. At the same time, fresh cows should not be vaccinated at this time since their immune system is compromised naturally.
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