Over the years, the dairy industry has done a tremendous job of breeding cows with the ability to produce large volumes of milk, with todays milk cow performing like a Ferrari within days of starting her lactation.
However, this ability has come at an expense. Metabolic challenges around the calving time have also increased. Data shows that up to 25% of cows that leave some dairy herds do so within the first 60 DIM. The transition period, defined as 3 weeks before and 3 weeks after calving, is an important and vulnerable period for the dairy cow. How well she adapts to the physiological changes during this time play a very important role in determining her productivity, health, and ultimately profitability. Each kg increase in Peak Milk production equals 200 additional kg of milk over the lactation. Research tells us that Peak Milk production can be 4.5-9 kg lower in cows that do not transition well. That means there is over 1800 kg of milk on the line, yet the dry cow often seems neglected and forgotten on farms. By providing the proper management and nutrition, producers can prepare their cows for a successful and profitable lactation. This article will cover some of the key practices for the transition cow.
Maximize Cow Comfort: The prefresh/maternity pens are the only pens on the farm that the cows get to decide when they leave, with every cow on the farm occupying the prefresh pen at least once a year. The biggest mistake that farms make is not designing their close-up area large enough. Even farms with a good reproductive program will have peaks and valleys to their calvings, just not as large of swings. To accommodate these swings, the transition/close-up pen should be large enough to house 1.3-1.5 x your average weekly calvings. Transition pens MUST be designed with ultimate cow comfort in mind. Stocking density should be 80% of maximum capacity, with the bedding pack allowing for at least 120 ft2 of clean, dry bedding per cow. When designing transition cow stalls, one needs to keep in mind that these cows, either heavy in calf or just recently fresh, need extra space for getting up and down. These stalls should be deep bedded stalls measuring 108+ inches long and 50+ inches wide for cows, and 48 inches for heifers. A low stress environment with adequate water access will translate into higher intakes, as well providing transition cows with a comfortable place to lie down will promote increased rumination times.
Manage the Feed Bunk: The close-up cow is the fussiest eater on the farm, with dry matter intake decreasing up to 30% in the last week or 2 leading up to calving. Keeping this in mind, care should be taken to get the feeding management right every day. Forages should always be fresh, mold free, and low in potassium and sodium. Energy intake needs to be controlled in both the far-off and close-up diets. These cows should not be able to sort, with the longest straw or hay particles being less than 1.5 inches and dry matter of the TMR at 46-48%. Water can be added if necessary. Each cow should have > 30 inches of bunk space and a minimum of 4 linear inches of clean, fresh water from 2 water sources per pen. The fresh cow diet should consist of good quality forages with adequate amounts of fiber to encourage feed intake during the early lactation period.
Minimize Transition Disease: Transition diseases can result in a considerable economic loss for the producer through decreases of up to 2-5 kg of milk per day at peak lactation. Research has also shown that there is a domino effect: when a cow suffers from one transition disease she is more likely to develop another. A cow with milk fever is eight times more likely to develop mastitis early in lactation. Any disease process that results in a moderate inflammatory response, such as metritis, mastitis, or even lameness, during the first 3 weeks after calving will have significant effect on both milk production as well as reproduction. Successful treatment of these diseases should not be considered a victory: it represents a significant loss of time, money, cow productivity and welfare.
Manage Heat Stress: Heat abatement is important for all dairy cows but is often overlooked in the transition group. If a dry cow experiences heat stress it can cause her to calve early, decrease her immune system function, decrease milk production in the next lactation, and even decrease the next lactation conception rate. Recent studies show that heat stress during the dry period can decrease DMI during the week of calving by nearly 50% and decreased peak milk production by more than 5 kg/day (do Amaral et al, 2011). Heat stress also effects the fetus and even the calf long after she was born. Calves born to heat stressed dams have a lower body weight and have lower milk production when she calves in as a heifer.
Implement cow- level and herd-level Monitoring: Progressive farms implement monitoring programs at the cow-level. Non-specific symptoms will often appear 5-10 days before onset of specific clinical signs. Monitoring for elevated or depressed body temperature, changes in milk composition or production, reduction in activity, and changes in feeding behavior can allow for early diagnosis and treatment decisions on an individual basis. These farms also incorporate weekly herd-level monitoring, such as urine pH and ketone testing to help indicate when changes are needed in feed and management.
By following these management practices, you can get your dairy cows the head start they need coming out of the transition period to ensure a healthy, productive lactation.
By: Dr. Lisa McCrea BSc, DVM
Dr. Lisa McCrea works out of Abbotsford, BC, as a member of the AgWest Veterinary Group. She has a passion for proactive herd health and dairy reproduction and is proud to provide an embryo transfer mobile service and IVF services for her clients.