Editor's note: This article originally appeared in our March 2015 issue of Dairy Herd Management. To read it in magazine form along with other articles from the month, visit: http://edp.dairyherd.com/magazine
Imagine a world where you bred heifers at 10, 11, or 12 months with little calving trouble and a seamless transition into the milking string. Today, some herds are living this dream, cutting costs from their heifer-raising program by actually increasing their cost of feed per day.
If a higher cost per day leading to more profit sounds counterintuitive, that may be because we were doing it wrong for decades. Instead of cost per day, Robert Corbett, D.V.M., recommends dairy producers take the meat industry approach – cost per pound of gain.
"Raising replacement dairy heifers is often treated as a major cost center," explained Corbett, president of Dairy Health Consultation, Provo, Utah, during the 2014 American Association of Bovine Practitioners annual meeting. "Heifers are often fed the cheapest feed, and provided the minimum inputs on facilities and labor until they approach the time of calving. What if we instead treated them as an investment, evaluating costs per pound of lean muscle gain, rather than as a set of daily expenses?"
Breeding early starts on day 0
Corbett fully supports what are called "accelerated" feeding systems from birth to weaning and on through breeding. However, he calls the systems "normal biological growth" – because they help animals meet their genetic potential.
If allowed, a dairy calf would nurse approximately 10 times per day, consuming an average of 20% of its body weight per day in milk, Corbett said. Assuming a Holstein calf weighs 85 lbs., 20% of its body weight would be approximately 2 gallons – twice as much milk as a calf would normally receive on a traditional program, especially those that are bottle fed.
"The calf should receive 10% of its body weight in high-quality, first-milking, clean colostrum as soon as possible after birth," Corbett said. "It is also recommended that a second feeding of first-milking colostrum be given at a rate of 5% body weight within 8 hours of the first feeding."
From there, he recommends a diet of milk replacers with 26%-30% protein and 15%-20% fat, or pasteurized whole milk.
"Young calves are more efficient at converting feed to body weight, and this should be taken advantage of when the calves are still on milk," Corbett said.
Current National Research Council (NRC) Nutrient Requirements for Dairy Cattle, with the standard 2 quarts twice a day of both 20:20 milk replacer and whole milk, should lead to weight loss if the environmental temperature drops to 32' F (0' C) according to computer calculations, Corbett explained. He recommends 15% of the body weight fed to the calf in the first week of life (about 3 quarts, twice a day). In Week 2, he recommends raising the total to 4 quarts, twice a day, or 20% of body weight.
"This amount should be maintained until the calf is eating enough of a high-quality starter to begin the weaning process," Corbett said.
Another way to increase milk solids is with "extenders," but only if a Brix refractometer is used and solids percentages are kept at or under 15% to prevent nutritional diarrhea; or 18% with great management and free-choice water available to prevent osmotic diarrhea.
"Do not increase the percent solids more than 2% during an adjustment," Corbett explained. "Sending new calves to a higher percent solids diet following colostrum can be done at the very next feeding, since colostrum is around 24% solids."
If your strategy leads to the growing popularity of computerized automatic milk feeders or ad libitum acidified milk, remember that group housing can increase the spread of infectious disease with poor facilities or management.
Weaning earlier isn"t better
"Another false paradigm that needs to be addressed concerning traditional milk feeding systems is that the earlier a calf is weaned, the better," Corbett said. "This has become a common management procedure for several reasons."
They include: milk and milk replacer being more expensive than dry feed; a belief that calves are more likely to get sick on milk; and third, that we should measure costs per animal per day.
"What is important is the cost per pound of gain of this animal, since size and weight are what determines the age at first breeding, as well as the appropriate size at first calving," Corbett contends.
Changing goals from weaning the calves early to creating a high-quality, healthy heifer calf should lead to an animal meeting maximum genetic potential for growth, economically, Corbett said. On the farm, many are starting to agree.
Are your youngstock fed the best feed available?
To get calves to be cows sooner and healthier, Corbett said many of his herds now feed their highest quality feed to the next generation, eliminating the term "heifer hay."
Corbett"s clients" starters have a minimum of 22% and up to 25% protein, in contrast to the 17%-18% starters typically available on the market. Corbett recommends soybean meal as the protein source, due to it being highly digestible, degradable in the rumen, and holding a good balance of amino acids. The higher protein profile allows a calf to eat 2 pounds for three days, rather than 4 pounds, to get the same nutrition before starting the weaning process. He recommends avoiding a starter with whole corn, and a textured starter pellet for higher palatability.
"Early consumption of calf starter is a sign of malnutrition. Initially, the calf will definitely consume less calf starter," Corbett said. "Calves drinking more milk will have more desire and ability to eat starter grain at 4 to 6 weeks, and should be consuming enough to start the weaning process between 7 and 10 weeks of age, depending on the size of calf."
Beyond high quantities of quality milk and starter, Corbett still sees free-choice water as a need for calves.
"Many people think that since milk is close to 90% water, it should satisfy the requirement for water," Corbett noted. "However, regardless of whether or not the calf sucks a bottle or drinks from a bucket, the esophageal groove closes and the milk bypasses the rumen and goes directly into the abomasum. Therefore, the water requirement for the rumen bacteria is not met unless additional water is consumed.
"Multiple studies have been done to show there is a significant increase in starter consumption when calves have free-choice water," he continued. "This also accelerates rumen development and the growth rate of the calf."
Weaning and beyond
When it"s time to transition the calf from milk and starter to a heifer ration, Corbett recommends keeping calves in the hutch for 1 to 2 weeks as starter increases up to 8 pounds per day. He groups calves 6 to 8 per pen if possible, but tries not to switch rations while switching housing.
After the calves are commingled for a week, he feeds the grower ration of 20% high-quality alfalfa hay (or another dry forage if not available) with 80% concentrate. The ration"s crude protein (CP) should be 20% to 22%, and heifers can consume this diet until 5 months of age.
At 5 through 8 months, Corbett introduces fermented forages and a ration with a total CP level around 18%. At 8 months, the ration changes to 16% CP, but metabolizable protein is going to yield about 1 pound more than metabolizable energy.
Finally, Corbett uses a breeding height of 51 inches at the withers as an appropriate breeding size.
"Heifers need to be bred when they reach the appropriate frame size, not according to body weight," Corbett said. "I like to use 51 inches at the withers for the height at which to begin breeding. I have found that on a good accelerated heifer growth program, approximately 28% of the heifers will reach this height at 10 months of age. About 60% will be ready at 11 months, and the rest by 12 months of age.
"Heifers raised on this program, which will allow them to reach their natural potential growth rate, will meet or exceed these goals set for a traditional program, will not have any increase in calving difficulties, and will produce more milk during their first and subsequent lactations."
He recommends culling the few that are delayed in reaching their breeding height, hopefully at about 400 pounds. Those shorter heifers will be poor producers and most likely to be culled for beef, he said.
Once confirmed pregnant, Corbett says metabolizable energy levels should be cut while maintaining metabolizable protein at about 15% or 15.5%.
You gain some, you save some
Corbett"s Dairy Comp 305 data shows cows had virtually no difference in their week 4, 12, and 305-day records whether they calved at 18 months or 24 months in one 1500-cow herd.
Further, earlier calving can open up opportunities for herd expansions or heifer sales. Lowering average age at first calving by three months results in 10 extra heifers per 100 cows with a 20% cull rate, or 21 per 100 cows with a 40% cull rate
"I have been feeding calves on my clients" dairies for more than 16 years on this type of program with great success," Corbett said. "The average death loss from birth to weaning is less than 1%, the cost of medicines used has decreased by approximately 80%, and the heifer calves are averaging around 260 lbs. at 10 weeks of age."