It starts from the moment the calf is born with well-managed maternity and nursery areas that focus on cleanliness and good colostrum management. Every heifer calf represents a potential replacement in someone’s herd and therefore should be considered as a future revenue opportunity.
Like all babies, newborn calves require a lot of extra care to keep them alive and healthy. Sanitation in the newborn’s environment is critical. The newborn calf is nearly devoid of immunity.
There is no transfer of antibodies from the dam to the fetus before birth, so the baby calf is completely reliant upon the protection coming from antibodies in the dam’s colostrum. The single-most important thing dairy farmers can do to significantly reduce the possibility of calves getting sick and dying is to feed high-quality colostrum within the first 12 hours of the calf’s life.
Pathogens just seem to be clamoring to kill baby calves, so a clean, dry maternity area is essential for minimizing the chances of infections at the time of birth.
The baby calf must be housed in a clean, dry pen protected from the weather. Practice the “dry knee” test often – if you kneel down on the calf’s bedding and your knee is wet when you stand again, it’s time to change the bedding.
No matter if you raise calves in hutches or cages, the environment must have fresh air circulating all the time – no heavy ammonia smells. Temperature must be such that you can (almost) work in your shirt-sleeves, and the availability of fresh drinking water is a must.
Non-contaminated whole milk or a high-quality milk replacer must be fed in a timely fashion. Remember, the newborn calf doesn’t have a functioning rumen and it will be a couple of weeks before it’s able to start digesting grains.
Low-fiber, high-energy calf starters can be offered a week after birth. It’s recommended that you don’t try to wean your calves until they are eating about 3 pounds of calf starter for three consecutive days.
The growth rate of neonatal calves is often compromised – especially during winter cold. The thermal-neutral zone is 50ºF, and 75ºF for calves under 1 month old. As outside temperature drops it takes many more dietary calories to maintain a desired growth rate.
A good rule of thumb is to increase dietary maintenance energy by 1 percent for every 1ºF drop below the thermal neutral zone. So even if it doesn’t seem very cold when its only 45ºF outside, the baby calf is already in need of additional calories to keep her healthy and growing.
When temperatures drop to below freezing, it requires 25 percent or more milk replacer to be fed to a calf every day.
Once the calf has been weaned and is on a steady diet of forage and concentrates, the labor intensity of the program declines significantly. However, the nutritional management is every bit as important for this stage of growth as it was when the calf was still a baby.
In order to sustain the recommended daily weight gain of about 1.75 pounds per day, the diet must be properly balanced for both energy and protein, along with vitamins and minerals.
Goals for a calf-raising program should be set for the particular breed of cow and aggressively monitored so heifers enter a milking herd at the optimal age and size.
Recommended growth characteristics at breeding and calving for most Holstein and Jersey herds are presented in Table 1.
A study conducted at Penn State University about a decade ago determined that for every month beyond 22 months old, it costs about 5 percent more to raise a heifer to calving.
In other words, by increasing the time to first-calving by two months (24 vs. 22 months), the overall cost to raise a heifer increases by about 10 percent, and increasing time to calving from 22 to 26 months increases costs by 20 percent just to get that same heifer in the milking string.
In addition, previous research from the USDA has demonstrated that Holsteins and Jerseys that calve at older ages are culled at an equal or slightly younger age than their earlier-calving herdmates. The end results are higher rearing costs for heifers that calve late and decreased productive life and lifetime profitability.
Essentially, an aggressively managed dairy replacement program means mortality rates for baby calves stay below 5 percent and heifers are in the barn and milking at 2 years old or less.
Sustaining a 30 percent annual culling rate in the average U.S. dairy herd comes at a sizable cost to a dairy farm and becomes even more costly if mortality rates are higher and breeding of young heifers is delayed. We spend a lot of time emphasizing the importance of improving feeding and breeding efficiencies for milk cows and tend to ignore what it costs to raise a replacement.
As the costs of production continue to increase for the industry, we must make certain that every heifer calf that’s born on the dairy is considered a valuable asset that has the potential to contribute to the financial bottom line. PD