Get ready for fall-calving now

Thursday, August 15, 2013

Fall-calving season is just around the corner, and that means cow-calf producers should be taking care of the cattle operation version of a “honey-do list.”

Glenn Selk, Oklahoma State University Cooperative Extension emeritus cattle specialist, said now is the time to get the calving kit ready and make certain the calving shed is clean, in good operating condition and ready for business.

“Producers with early fall-calving cows should expect calves to start coming several days ahead of the textbook gestation table dates,” he said. “They should begin routine cow checks at least a week to 10 days ahead of the expected first calving date.”

Consider what OSU livestock physiologists found during a study of early fall (August) and late fall (October) calving cows, as reported in the 2004 OSU Animal Science Research Report. Data from two successive years were combined for 50 Angus x Hereford crossbred cows. The “early” and “late” fall calving cows had been artificially inseminated in early November or early January respectively.

“Semen from the same sire was used for all cows,” Selk said. “All cows were exposed to a single cleanup bull for 35 days at four days after the artificial insemination season.”

The weather prior to calving was significantly different for late pregnancy in the two groups. The average maximum temperature the week before calving was 93 degrees Fahrenheit for the “early” fall group. The average maximum temperature the week before parturition in the “late” calving group was 66 degrees Fahrenheit.

“There was a 100 percent survival rate for calves in both groups and both groups of cows had very high rebreeding rates of 90 percent and 92 percent respectively,” Selk said.

The average gestation length for the “early” cows was six days shorter – 279 days – compared to the “late” cows – 285 days – in the first year of the study. The average gestation length for the “early” cows was four days shorter – 278 days – compared to the “late” cows – 282 days – in the second year.

“That is the science behind the OSU Cooperative Extension recommendation for producers to start getting ready now, and to begin routine cow checks at least a week to 10 days ahead of the expected first calving date,” Selk said.

The Oklahoma Cooperative Extension Service is one of two state agencies that are part of OSU’s Division of Agricultural Sciences and Natural Resources, along with the division’s research component, the statewide Oklahoma Agricultural Experiment Station system.

Cattle and calves represent the number one agricultural commodity produced in Oklahoma, accounting for 46 percent of total agricultural cash receipts, according to National Agricultural Statistics Service data.