Cow-Calf Corner: Beef replacement heifers and herd expansion; The third stage of calving – shedding of fetal membranes

Feb. 13, 2017
Beef replacement heifers and herd expansion
by Derrell S. Peel, Oklahoma State University Extension livestock marketing specialist
The U.S. beef cow herd was 31.2 million head on Jan. 1, 2017. The beef cow herd has expanded a total of 7.3 percent since the recent low on Jan. 1, 2014 (Table1). The inventory of beef replacement heifers relative to the beef cow inventory is the best indication of future beef herd expansion. The Jan. 1, 2017, ratio of replacement heifers to the cow herd was 20.6 percent, down slightly from one year ago. The 2016 ratio of 21.0 percent was the highest in 48 years. The heifer ratio has been sharply highly since herd expansion began in 2014 with the last three years having the three highest levels since 1969. The four-year average since 2014 is 20.4 percent. The average for the 25 years prior to 2014 was 17.3 percent. The current ratio of beef replacement heifers to the cow herd suggests that herd expansion will continue relatively aggressively in 2017. There are differences across regions, however.
Table 1.

*2017 U.S. Beef Cow Herd: 31.2 million head
The long term average shows that beef replacement heifer ratios are generally higher in the northern part of the U.S. with the largest average ratios in the Northwest, Northern Rockies, Northern Plains, Great Lakes and Northeast regions. This may be due to the colder climate, different cattle types, and higher proportions of purebred operations. These regions currently account for 29.4 percent of beef cows. The lowest average ratio is found the South (AL, GA, FL) although the lowest ratio in 2017 is in the Appalachian region (KY, TN, WV). In fact, the Appalachian region is the only region where the 2017 heifer ratio is below the long-term average. This may indicate that little additional expansion is to be expected in this region. Based on the current heifer ratio compared to the long term average, the Northwest, Great Lakes, Gulf and Eastern Seaboard regions may also show relatively slower herd growth in 2017. Continued stronger growth is likely in other beef cow regions including the northern and southern Rockies, northern and southern Plains and the Midwest.
The Southern Plains (KS, OK, TX) is the largest beef cow region with 26 percent of the national total (8.13 million head in 2017) and has added the most beef cows of any region since expansion began. The region has added 14.1 percent to the beef cow inventory, accounting for 47.3 percent of the 2.12 million head of additional beef cows nationwide since 2014. Nevertheless, the current Texas beef cow inventory is still down more than 600 thousand head from average pre-drought levels. Herd expansion is expected to continue in Texas though a complete return to pre-drought levels may not be likely. The number of beef replacement heifers (and the heifer ratio) dropped in Oklahoma in 2017, suggesting perhaps a slower rate of herd expansion in the number two beef cow state this coming year. Oklahoma has already expanded rapidly since 2013 and is currently at the highest beef cow herd inventory in the state since 1984. Kansas is also at the largest state beef cow inventory since 1984.
 
The third stage of calving: shedding of fetal membranes
by Glenn Selk, Oklahoma State University Emeritus Extension animal scientist
The process of “calving” or parturition in beef cattle is defined by three stages. Stage I occurs about 4 to 24 hours prior to calving. The major event during stage I is the dilation of the cervix. Stage II occurs in about 30 minutes in adult cows and about 1 hour in first calf heifers (when all goes well) and is the time when the calf passes through the birth canal and is delivered into the world.
The third stage of calving is the shedding of the placenta or fetal membranes. In cattle this normally occurs in less than eight to 12 hours. The membranes are considered retained if after 12 hours they have not been shed. In some rare cases, the entire placenta is held in the uterus so there is no exposed portion. This condition may go unnoticed until the cow shows an abnormal uterine discharge or an odor characteristic of tissue degeneration.
Years ago it was considered necessary to remove the membranes by manually unbuttoning the attachments. However, research has shown that improper manual removal can be detrimental to uterine health and future conception rates. When a cow calf operator notices a cow that “did not clean” in 12 hours after calving, close observation is suggested. If the cow shows any signs of ill health, such as droopy ears, lethargic behavior, or poor appetite, this may indicate that an infection of the uterus has begun. Contact your local large animal veterinarian for the proper management of retained placenta. Administration of antibiotics usually will help against infection and the placenta will usually slough in four to seven days.
More information about working with cows and heifers at calving time can be found at the Oklahoma State University Extension publication E-1006  “Calving Time Management for Beef Cows and Heifers”.
Cow-Calf Corner is a weekly newsletter by the Oklahoma Cooperative Extension Agency. More information is available at sunup.okstate.edu/category/ccc.