Cow-Calf Corner: Fewer cattle imports from Mexico and Canada in March; Cow disposition affects pregnancy rate

May 8, 2017
Fewer cattle imports from Mexico and Canada in March
by Derrell S. Peel, Oklahoma State University Extension Livestock marketing specialist
Total U.S. cattle imports were down 7.4 percent in March compared to one year ago. Monthly imports of cattle from Mexico were down about one percent while cattle imports from Canada were down 17 percent year over year. For the first three months of the year, total cattle imports from Mexico are up 24.3 percent while imports from Canada are down 18.5 percent leading to a combined year-to-date cattle import total up 5.6 percent compared to the same period one year ago. Total annual cattle imports from Mexico and Canada in 2016 were 1.71 million head, down 13.9 percent from the 2015 total, and the lowest total cattle imports since 2004.
Annual cattle imports from Mexico decreased 18.3 percent year over year in 2016 to a total of 943,043 head. However, monthly cattle imports from Mexico increased year over year from last November until the slight decrease in the latest March data. Stronger U.S. cattle markets and the sharp devaluation of the Mexican Peso following the election both contributed to the increases from November through February. 
For the 3-month year-to-date total, steer imports from Mexico are up 17 percent year over year. Most of the increase is in lighter-weight steers (under 450 pounds). This may indicate that steers are being exported earlier rather than waiting until weights are heavier later in the year. Imports of spayed heifers from Mexico are nearly double, up 98.1 percent, from the same period one year ago.
For the year-to-date, heifers account for 14.9 percent of total Mexican cattle imported compared to 9.4 percent one year ago. Last year’s heifer export rate was lower than is typical and suggested more heifer retention and herd rebuilding. However, the current rate may indicate that heifer retention in Mexico is slowing. Despite increased imports of Mexican cattle in January and February, the data suggest that exports were somewhat front-loaded early in the year and will not continue to increase year over year. March imports were about equal to last year and preliminary weekly data for April indicates a significant year over year decrease in imports of Mexican cattle.
Cattle imports from Canada totaled 764,970 head in 2016, down 7.8 percent from 2015. Cattle imports from Canada include feeder steers and heifers, slaughter steers and heifers, and slaughter cows and bulls. In 2017, year-to-date total slaughter cattle imports from Canada are down 15.0 percent including a 40.9 percent decrease in slaughter cows and a 14.9 percent decrease in slaughter heifers year over year. Slaughter steer imports from Canada are up 18.6 percent from last year while slaughter bull imports are up fractionally. Total slaughter cattle imports from Canada include 69.2 percent slaughter steers and heifers and 30.2 percent slaughter cows and bulls. Total feeder cattle imports from Canada include steers, down 56.8 percent from last year and heifers, unchanged from one year ago. Feeder heifers account for 73.7 percent of total feeder cattle imports from Canada so far this year with steers counting for less than one-quarter of feeder cattle imports. In 2016, feeder heifers accounted for 61.1 percent of total feeder cattle imports from Canada. Total cattle imports from Canada so far this year consists of 27.0 percent feeder cattle, 48.8 percent slaughter steers and heifers and 21.8 percent slaughter cows and bulls plus 2.4 percent of beef and dairy breeding animals.
 
Cow disposition affects pregnancy rate
by Glenn Selk, Oklahoma State University Emeritus Extension animal scientist
Now we have another good excuse to cull cows due to bad temperament. Producers that routinely breed cows artificially realize that cows that are unruly and nervous are less likely to conceive to artificial insemination. Presumably the lowered conception rates were because they have been stressed as they are passed through the working facilities and restrained while being synchronized and inseminated. Now it seems that, even in the serenity of a natural breeding pasture, cows with bad dispositions are less likely to conceive when mated with bulls.
University of Florida animal scientists recorded disposition scores over two years on 160 Braford and 235 Brahman x British crossbred cows. They wanted to evaluate the effects of cow temperament and energy status on the probability to become pregnant during a 90-day natural breeding season. Cows were scored as 1= calm, no movement to 5= violent and continuous struggling while in the working chute. Also, a pen score assessment was assigned as 1= unalarmed and unexcited to 5 = very excited and aggressive toward technician. An exit velocity speed score was measured as the cows exited the working chute as 1=  slowest and 5 = fastest. An overall temperament index score was calculated by averaging the chute score, pen score and exit velocity score. Blood samples were analyzed for cortisol concentrations. Cortisol is a hormone released when mammals are stressed or excited. Increased cow temperament score and elevated plasma cortisol concentrations both were associated with decreased probability of pregnancy. These results suggest that excitable temperament and the subsequent elevated cortisol concentrations are detrimental to reproductive function of cows. These authors concluded that management strategies that improve cow disposition, enhance their immune status, and maintain the cow herd at adequate levels of nutrition are required for optimal reproductive performance. Source: Cooke and co-workers. 2009 Florida Beef Research Report.
Cow-Calf Corner is a newsletter from the Oklahoma Cooperative Extension Service.