Raising Replacement Dairy Heifers
Published on Wed, 02/10/2021 - 9:43am
Raising Replacement Dairy Heifers.
By Heather Smith Thomas.
Good heifers are the future of a dairy, so it’s important to raise or have someone raise your heifers to grow optimally—ready to become healthy, high-producing cows. Dr. Bob James, a dairy consultant with GPS Dairy Consultants and owner of Down Home Heifer Solutions, Blacksburg, VA (Former Extension Scientist at Virginia Tech) specializes in calf health and nutrition. He works with many dairies across the country, helping them do a good job with their young stock. He was a founding member of Professional Dairy Heifer Growers, now called Dairy Calf and Heifer Association.
“I got to know a lot of heifer growers, from California to Florida, and New England. There are many ways to raise dairy calves and replacement heifers. My specialty was the babies and this is still what I’m doing. I work with pre-weaned calves, from birth 80 or 90 days of age,” he says.
“These are babies, and they need the best care you can give. This is not a time in their lives to be cheap. The dairy industry is weaning calves at 6 to 8 weeks of age, and often wean by reducing the milk, feeding them just once a day. This is hard on those young animals,” he explains.
“People wean this early to save money and reduce labor, but this is not biologically normal. Early weaning combined with once-daily feeding is challenging for these calves,” James says.
“I prefer to have them drink as much milk as they want to, for at least the first 30 days, putting on a little body fat. I don’t worry about developing the rumen of 30-day old calves; they just need plenty of milk. The challenge is that most people are only feeding them twice a day. In an ideal situation I’d like to have them fed at least 3 times a day.” This is a more natural situation.
“I also work with computer calf feeders, and those babies actually drink milk 6 to 8 times a day, drinking whenever they want You limit them to how much they drink at any one meal, but they can drink multiple times through the day—which is what they would do if they were nursing the cow,” he says. This is easier on the calf’s digestive system.
“If it’s a Holstein calf I want it consuming at least 2 gallons per day by the end of the second week. Historically we only fed calves one gallon a day—2 quarts in the morning and 2 in the evening. That’s not enough to meet their nutritional requirements, particularly in winter in a cold climate,” he says. Calves have nutrient requirements for growth and maintenance. During cold weather limiting milk, or poor-quality milk replacer, may not provide enough nutrition for maintenance requirements. This may result in poor growth and likely has a negative impact on health. Feeding enough milk (more than one gallon per day) also improves efficiency of gain.
“At about 6 weeks of age I start tapering them off the milk. Though many farms wean calves by once-a-day feeding, this is traumatic for the calf. Instead of feeding 4 quarts twice a day or 3 quarts 3 times a day, back it off a quart at each feeding, for a week,” he suggests.
Then if a person wants to cut those calves down to once-a-day feeding, it’s not as hard on them. “If you back them off gradually, they start eating more grain and solid feed and the rumen is developing. Earlier gradual step-down in milk stimulates consumption of calf starter grain and promotes adequate rumen development with less stress on the calf.”
In one dairy he works with, they’ve made some adjustments in their feeding plan with automatic calf feeders by allowing more milk early on, followed by a step-down milk feeding program for three weeks before weaning. “Before those changes, the calves were lucky to be eating 2 pound of grain per day when we weaned them. Now they are eating 6 pounds a day by the time we wean, because we fed them more milk early on. They grew really well during their first 30 days, and we backed them off gradually, feeding a really good calf starter,” he says.
“A good calf starter should be at least 18% protein and I prefer 20% --with ingredients that are palatable, to encourage intake. We get them past weaning, and then the next challenge—if we’ve had them in individual pens—is sudden adjustment to being in a group pen.”
They are not used to being with other calves, so this is another big adjustment. The stress of weaning needs to be more gradual—tapering off on the milk, and providing a high-quality calf starter. “The advantage of the automatic calf feeders and group housing is that these calves have already been in a group and are more at ease with it. Not every dairy can do this, but some farms house calves in pairs beginning at least 4 weeks of age, prior to weaning. This can achieve the same benefits of earlier starter intake and less stress associated with individually housed calves.
“Several weeks after weaning we shift from a starter to a grower ration, which will be a little cheaper, and we might back the protein off to 16%. Once that calf reaches 6 months of age and has good health and a strong appetite, we have a lot more flexibility in what we might feed it,” he says.
James has worked with many western growers who use a wide variety of feeds for heifers. “By that time in their lives they are eating well. They need energy and protein, minerals, vitamins, etc. but where they get these nutrients can be a lot more flexible. I’ve worked with growers in Colorado who use brewers’ grains or beet pulp—whatever is available that works and is less expensive per unit of nutrient,” he explains.
“These animals will eat it, and it just needs to be fresh and safe to consume. Some of the by-products we can feed heifers may have harmful residues that we must watch out for. Traditionally, heifer diets for calves 300 pounds and up have been largely corn silage and some type of long-stem forage that may be chopped. Ideally, I’d like to have it provided by a TMR where everything is all blended together,” he says.
Beyond meeting nutritional requirements of these heifers, it’s a matter of having a good vaccination program and good consistency in feeding management and care. “It’s not rocket science after we get them to 600 pounds or more. In winter we simply feed more, because their nutrient requirements, especially for energy, increase in cold weather.”
They need more calories just to generate enough body heat to stay warm, but if they are dry (not out in the rain or snow) and their hair coat is still standing up and fluffy (not plastered down and wet) they can withstand cold weather. If they’ve been in a muddy pen and the hair coat is lying down and wet, it has lost its insulating quality, and their maintenance requirements increase tremendously. “At one time I worked with a farm in Wisconsin when we couldn’t feed 12 to 14-month-old heifers enough of a TMR to keep them growing because their hair coats were wet--resulting in a dramatic increase in energy requirements,” says James.
Many things have an influence on nutrient requirements, including weather and exercise. “If dairy heifers are confined, where all they can do is stand up, lie down, and eat, feed efficiency increases tremendously. In that situation you must reduce the amount of energy fed, so they won’t get too fat.”
Heifers older than 12 months in confinement housing need less and you may have to limit-feed them or include lower energy forages to prevent over fattening.
When heifers hit 12 months, and up to 22 months, you should formulate the diet based on their body condition and how much flesh they are carrying. “Some of the more progressive dairies and heifer-raisers, any time they work heifers or put them through the chute they run them across a set of scales and measure body weight,” says James.
In a beef herd with heifers raised on pasture there can be a lot of variability on growth rate. “That can be challenging for dairy heifers depending upon their age. Typically, dairy heifer do best when rates of gain are consistent, enabling them to achieve growth goals at freshening. When better weather comes along they have compensatory growth.
If you shortchange young calves (prior to reaching puberty) on nutrition, they don’t catch up as much on growth later. “They lose some of that growth potential and never get quite as big in stature. But after they’ve reached puberty, you have more flexibility. I’ve seen heifers that in February were only gaining 1.25 pounds per day, and then when pasture is good—later in spring—some of those heifers will gain 3 pounds per day just on pasture, without any grain at all,” he says.
“After heifers reach about 10 months of age there is a lot you can do in terms of feeding them economically and they can do very well. With the babies, however, there is less wiggle room because they need a much higher quality of protein and energy in their diets,” says James.
A beef calf puts on some fat in the first weeks of life and a dairy calf should do the same. You want them healthy, with some reserves in body condition. “If they get sick, they don’t eat, and they need that reserve. You want to make sure they have it.”
In summary, a pre-weaned calf needs high-quality nutrients—meeting requirements for growth as well as maintenance. “I don’t worry as much about rumen development for a calf before one month of age, because this takes care of itself if we have a well-grown animal,” he says.
“Weaning is a challenge because ideally we want a more gradual reduction in milk. I know this isn’t easy for some farms, but we should think about what’s right for the calves. They need a starter with sufficient protein and energy, with high palatability and digestibility, and then we need to make a non-stressful transition to group housing. Once we get them growing, and up to 12 or so months of age, we have more flexibility in what kind of feed they receive,” he says.
Traditionally, and in many parts of the country, corn silage and small-grain silage works well, supplementing the corn silage because it’s too low in protein. “I’ve worked with places in California where we fed a lot of by-products. It might be citrus, almond hulls, brewers’ grain, or lower-quality legume forage. I worked with a fellow in Colorado who had a standing order with hay suppliers; if a cutting of alfalfa got rained on, he’d take it. It wasn’t high-quality enough for a dairy, but growing heifers could use it very effectively,” says James.
“It’s amazing what you can feed older heifers, and there’s where you can economize. Then the next step is to have them bred, and calving at about 22 to 24 months. It all takes good monitoring and good management.”
He works with one operation that grows heifers and has about 600 to 700 head on pasture. “They also have silage, and if they don’t have good pasture they put the heifers on a TMR. They take in heifers at about 300 pounds and send them back to the dairy about 2 months before they freshen,” he says. This works very nicely.