During the recent conference of the Academy of Veterinary Consultants, Trey Patterson, PhD, who is COO of Padlock Ranch Company, Ranchester, Wyoming, outlined the ranch’s systems approach toward developing replacement heifers.
Patterson notes the average net present value of females in the herd is lowest in their first year, peaks around year four or five and declines from there. The low initial value is due primarily to high production costs for replacements, failed reproduction in young females and reduced value of open females on the market.
Noting recent large increases in the cost of production for replacement heifers, Patterson suggests rethinking goals in developing heifers. For many operations, the goal is to get as many heifers bred as possible. At the Padlock, the goals have shifted to:
- Generate necessary replacements.
- Get heifers bred early in the breeding season.
- Minimize calving difficulty.
- Enhance longevity in the cow herd.
- Develop heifers cost-effectively.
Recent research has shown heifers do not need to be developed to 60 to 65 percent of mature body weight by first breeding as traditionally believed. Researchers at the University of Nebraska compared low-gain development to 53 percent of mature body weight with high-gain development to 57 percent of bodyweight. They found no difference in pregnancy rates, calf birth weights, birth dates or the percentage of females remaining in the herd for at least three years. In another trial, they found conception during the first 30 days of breeding was 16 percent higher in heifers developed to 55 percent of bodyweight compared to 50 percent, but no difference in overall pregnancy rates. The low-gain program saved about $28 per head in development costs.
Based on these results, managers at the Padlock shifted to a low-gain, low-cost range development system for some of their replacement heifers and compare results with heifers developed in a drylot setting. The range heifers, supplemented with distillers’ grains cubes, gain more slowly through the winter, but in the month before breeding, from mid-May to mid-June, they make up most of those lost gains as forage conditions improve.
The Padlock breeds a higher percentage of heifers than typical, using one-time artificial insemination as the final selection criteria. They use Wagyu AI sires for heifer breeding for calving ease and high calf value. They select their replacements from the heifers that conceive, and sell the rest as bred replacements. Open heifers become stocker cattle, and sell at a profit. The low development costs, Patterson says, make that possible. The Padlock breeds some open cows for fall calving and sells them, and even their cull cows typically sell at prices higher than development costs.
Patterson believes this system can help develop more efficient cows in the long run. He notes research conducted at the USDA’s Fort Keogh research station in Montana comparing feed-restricted cows with non-restricted cows, and comparing their heifer progeny. The restricted females were developed with 27 percent less feed than non-restricted. They had lower body weights for the first five years and a 3.5 percent reduction in pregnancy rates. When the researchers compared restricted cows from restricted dams versus unrestricted cows from unrestricted dams and restricted cows from unrestricted dams, they found the restricted cows from restricted dams had the highest retention rates in the herd.
Patterson says a low-cost heifer development system resulting in heifers bred at 50 percent mature weight can reduce conception rates, but does not necessarily reduce profits because open yearling heifers can be marketed profitably. The young female, he says, is an important part of the herd to focus management. Heifers can perform well when developed on range, and the Padlock has seen improvements in calving rates among their two- to three-year-old cows and a higher percentage of cows calving early in the season.
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