Replacement Heifers

 
For the last five years, production of milk replacement heifers has been on the rebound in the United States. But US born replacements may decline in coming years, for the same reason they’ve been rising, Canada, long prohibited from supplying the US dairy cow market, is back in business. Imports of Canadian breeding cattle were barred on May 20, 2003, the day the Canadian Food Inspection Agency revealed a native-born cow had tested positive for bovine spongiform encephalopathy, better known as mad cow disease.

 Canada had been a steady source of 50,000 dairy cows a year to the US; the border did not reopen to intact Canadian cattle until November of 2007.
In the interim, retention of female dairy bred calves has surged. According to USDA’s annual cattle inventory report, milk replacement heifers as of January 1 averaged a little less than four million from 1988-2005 and never exceeded 4.18 million; the last three years, they’ve jumped to 4.275 million, 4.31 million and 4.457 million.
But now, here come the Canadians. 44,000 dairy cows crossed the border in the first ten months of 2008. “It’s really had a large impact on the overall milk production,” says Jodie Pennington, Extension dairy specialist at the University of Arkansas, “as well as the price of replacement heifers. Before, when our dollar was really strong, it was almost more expensive to buy a Canadian heifer and bring it here than you could buy one locally. As the dollar has gone down this year, there have been tremendous quantities of Canadian heifers crossing the border.”
In part, that’s because some people prefer the Canadian cattle. Pennington says they’re perceived as being bigger and healthier than their American cousins, and they also produce a little more milk. “As you go north,” he says, “generally speaking, cattle are larger. Cattle like colder weather. As you get south, of course, we have more problems with heat and humidity, so heifers don’t grow as well.”
Doug Block, a Pearl City, Ill. dairyman, says the availability of dairy replacement heifers has decreased over the years, particularly in the Upper Midwest, where many dairymen have retired. Most dairy producers, unless they’re expanding, keep their own replacements, and retiring producers sell out to neighboring farms. “I was just talking to a dairyman from Arizona,” Block said, “and they had 170,000 cows ten years ago. Today they have 170,000 cows, but they only have 80 dairy farmers; ten years ago they had 180 dairy farmers.”
However, Block, who farms with his brother Tom, has fairly recent expansion experience. The Blocks started ten years ago, expanding a 70-cow dairy to 400 head; now, after building a new barn a couple of years ago, they have 800. But they prefer to use calves from their own herd as replacements. Doug says, “We’re in control, number one, of the genetics of that animals. And by that I mean, we get nice leg conformation, we get nice udders, we’re aware of the sire and the dam, and the ability to produce milk.”
The second advantage is familiarity with each animal’s health history. “If a baby calf would happen to have pneumonia or something as it’s young,” Block says, “and have a bad lung where it’s marginal, you may not be able to pick that up. If you would happen to buy a bred heifer and that animal has lung damage; she may be growthy and everything, but won’t be challenged until the weather changes, or when she has a calf, that’s a high-stress time.”
Two former dairymen raise the Blocks’ replacement heifers. “They decided they didn’t want the challenges of milking twice a day, every day,” Doug says, “and now they’re feeding and raising dairy heifers for us.” The Blocks deliver the calves at about six months of age, and get them back at 22 months; in the interim, they’re bred. There are a few heifer calves that don’t make it back into their herd. “We have a small percentage that we sell off as young stock,” he says. “If they’re not growthy, if they’re shorter than the others, if they’re not the size, or if they have a poor body conformation, we sell those as young animals, at about 6-7 months of age or earlier.”
The Blocks actually generate a fair number of extra animals; about 43% of their live calves are heifers, and their cull rate is 25-30%, so the balance can either go onto the market or be retained to further expand the herd. The market sources for replacements vary; in addition to consignment auctions, dairymen getting out of the business or selling off their own excess heifer calves, there are also dealers for replacement heifers. Block says, “The Holstein Association actually has an individual who, if I have extra bred heifers for sale, I’ll contact them, or if I’m looking for bred heifers to buy, I’ll contact them. That’s part of their business profile.”
Block says when they cull a cow, most frequently it’s because they can’t get her to breed back; a myriad of health problems are the next most common reasons. “That could be a foot or a leg problem,” he says, “or udder injury. Again, many of these things go back to genetics; if they have an udder that’s very low, that’s very close to the ground or something, that animal is not likely to be in the herd a long time because she’s more prone to injury, she’s more prone to picking up a health issue with that poorly conformed udder. And likewise, with the legs; if they have poor foot and leg conformation, a shallow heel, they’re more prone to a foot injury. Some of them take more trimming, but the genetics of them are they’re more prone to injury.” And., of course, if a cow’s milk production drops off, she’s also likely to be shipped to town.
UA’s Pennington says it’s not uncommon for larger dairies to use farms for raising their replacements; that way, they can all be vaccinated at the same time, and they’re subject to the same conditions so they grow at the same rate. He says, “Some of the larger dairies also require that they weigh the animals, and when they sell them they weigh them out, and it’s that difference in weight that they get paid for. So there’s incentive for trying to keep as many alive as possible.” A few bigger operators in Arkansas raise 500 or more, but most are under 100; they maintain heifers for dairies as far away as Indiana.
He also says dairymen normally don’t hurt themselves by keeping their own genetics in the herd. “Most cases have animals that are adapted to their farm,” Pennington says, “and if you keep those animals, sometimes they fit in better than bringing an animal from another farm. For example, if you bring in heifers from up north in the summer, sometimes if they calve here in the hot weather, they don’t do very well just because of the fact that they’re not used to the heat stress.” He says producers may need heifers, though, just from a run of bad luck, their cows will produce a lot more bulls than heifers. But Block points out modern dairying technology has addressed that problem in the form of sexed semen, which will yield about 90% females.
For those who do have to enter the market for replacements, Block says the reputation of the supplier is crucial. “The vaccination program and the health of that heifer are very important…more important than the genetics, so we need to find a source that can assure of the first characteristic primarily, and second characteristic if we can have it available.” That, he says, can come from dairymen who are selling out, or from people in the business. Either way, though, you want to deal with “people that you know you can trust.”
 

 

 
Jodie Pennington, Ph.D., 
is professor of Animal Science and Extension Dairy Specialist at the University of Arkansas Cooperative Extension Service, Little Rock-- He works as the only Extension dairy specialist in the State in all areas of dairy management, including acting as liaison with dairy farmer groups and industry; works extensively with sustainable agriculture, including organic dairy production, in the State and routinely conducts field demonstrations with dairy producers on reproductive management and forages for the dairy herd; conducts surveys and evaluations of herd performance; has worked with entomologist to complete studies with use of parasitoids (fly parasites) to control flies on dairy farms. Pennington has over 400 publications, many in the popular press, and also works with various aspects of goat production.