Early weaning as a herd-management practice continues to be a viable alternative for cattle ranchers across a big chunk of the U.S. Certainly for producers in drought-prone regions of the West and Great Plains, it's a tool that can be used to avoid culling cows and maintaining high levels of reproductive performance among young cows.

Researchers continue to explore the practicalities and economics of various early-weaning systems. Richard Waterman, range nutritionist, and Tom Geary, reproductive physiologist, both working at USDA's Fort Keogh Livestock and Range Research Laboratory, Miles City, MT, have been leading an extensive early-weaning research effort.

They emphasize that weaning beef calves at or before breeding will increase initial cash costs and increase management responsibilities for production. But, they say, early weaning may prove to be a valuable alternative to traditional management practices once all facets of production have been fully assessed (Table 1).

“The increased value of early-weaned calves alone at time of normal weaning may not offset the cost of early-weaning diets as we've used them,” Waterman says. “The value of early weaning may, however, come from improved feedlot gain and carcass improvements. Ranchers may also see increased conception rates for not only the year early weaning occurred, but for the subsequent year as well.”

Early-weaning considerations

Fort Keogh research indicates herd sustainability may be optimized by early-weaning calves:

• During times when forage quantity and/or quality are insufficient to meet cow requirements (e.g., drought).

• When there is concern about cow body condition going into winter and reproductive success for the subsequent year (especially, two- and three-year-old cows).

• When consequences of extended drought may lead to extensive liquidation of cowherds, which may result in loss of genetic diversity and recent herd advancements.

• Easing the pressure to liquidate, simply by reducing the nutritional demands of lactation, thereby reducing forage consumption and optimizing the opportunity for a cow to rebreed.

The Fort Keogh study on two groups of early-weaned calves also shows weaning at the start of a synchronized breeding season increased artificial insemination (AI) pregnancy rates (Figure 1). Early weaning also increased breeding season pregnancy rates and increased cow weight at the time of normal weaning. The greatest increase in weight gain was among two-year-old cows.

“Improvements in pregnancy rates were observed across all age groups,” Geary says. The magnitude of improvement in AI pregnancy rate is greater than has been reported with temporary calf removal.

“We know that suckling delays the onset of estrus in beef cows,” Geary explains. “And weaning before the breeding season has been reported to shorten the postpartum anestrous period and increase conception rates.”

As noted, early weaning increases the initial cost of producing beef steers and heifers and intensifies management obligations to construct facilities or make accommodations to manage young calves.

“But calves weaned at 70-150 days of age often exhibit improved average daily gain (ADG) and are subsequently heavier at time of traditional weaning or 205 days of age,” Waterman says. “In addition, early-weaned steer calves have been shown to grade higher than traditionally weaned calves on similar diets.”

Therefore, he adds, livestock producers may be able to recover the initial cash cost due to early weaning, and possibly receive a premium for their calves.

Continue reading on Next Page>