Source: The Cow/Calf Corner newsletter from the Oklahoma Cooperative Extension Service

Jan. 26, 2015

Oklahoma drought, winter grazing and forage update
by Derrell S. Peel, Oklahoma State University Extension livestock marketing specialist

Parts of southern Oklahoma and specifically southeastern Oklahoma received rain in the past couple of weeks. Last week also brought rain and snow to parts of western Oklahoma including a band of wet snow along Interstate 40 in west-central Oklahoma that contributed up to an inch of precipitation across several counties. All in all, however, it has been relatively dry this winter in much of the state. As a result, severe drought conditions persist in areas of southwestern and northwestern Oklahoma, including parts of the Oklahoma Panhandle.

These severe drought areas have expanded slightly through the winter, but perhaps more disturbing is that marginal drought conditions have redeveloped across much of the state. The latest Drought Monitor indicates that the areas of worst drought (D3 and D4) have increased from 20.87 percent of the state three months ago to 22.58 percent in the current map. However, the total region of the state classified as abnormally dry or worse has expanded from 70.41 percent of the state as late as a week ago to 94.97 percent in the current U.S. Drought Monitor map. These redeveloping drought conditions are not so much an immediate threat but do represent a potentially huge threat as spring approaches.

Winter wheat in Oklahoma was rated in generally fair to good condition in the latest crop progress update for the state released by the National Agricultural Statistics Service (USDA-NASS) in early January. In the same report, USDA-NASS indicated that 41 percent of wheat was being grazed this year, up from last year and the average level, both at 32 percent. More stocker cattle are grazing wheat this year than in several years and livestock conditions are generally rated as good. However, dry conditions, coupled with some earlier cold temperatures, have sharply slowed wheat growth recently and wheat forage supplies are dwindling fast. A few cattle are already being pulled off wheat and sold and the pace will accelerate in the coming weeks. If forage holds out, winter wheat grazing will continue another three to five weeks for wheat producers intending to harvest a grain crop. Wheat grazing termination depends on the date of first hollow stem in the wheat, which depends on the year, the wheat variety and the location. Some producers will be evaluating the decision to harvest wheat versus graze-out in the next month.

USDA-NASS recently released the 2014 hay production and stocks data. Total 2014 hay production in Oklahoma was up 23 percent from one year ago and up 37 percent over the five-year average prior to 2014. Other hay, which accounts for 83 percent of Oklahoma hay production, was at the highest level since 2007. Alfalfa hay production in 2014 was at the highest level since 2010. Stocks of hay in Oklahoma on Dec. 1, 2014, were reported at 5.1 million tons, up 31 percent from last year and 37 percent higher than the previous five-year average. It is the highest Dec. 1 hay stocks level in Oklahoma since 2007. 

Cattle producers generally have adequate forage supplies to finish the winter.  Producers should carefully monitor local drought conditions as the new growing season approaches. Hay supplies may provide critically needed flexibility if spring forage growth is limited or delayed. Producers should have a management plan in mind that covers a wide range of moisture scenarios that could develop this spring.

Signs of impending calving in cows or heifers
by Glenn Selk, Oklahoma State University Cattle Emeritus Extension animal scientist

As the spring calving season approaches, the cows will show typical signs that will indicate parturition is imminent. Changes that are gradually seen are udder development, or making bag and the relaxation and swelling of the vulva. These indicate the cow is due to calve in the near future.

There is much difference between individuals in the development of these signs and certainly age is a factor. The first calf heifer, particularly in the milking breeds, develops udder for a very long time, sometimes for two or three weeks before parturition. The swelling and relaxation of the vulva can be highly variable too. Most people notice that Brahman influence cattle seem to change in this area much more than cattle from other breeds.

Typically, in the immediate 2 weeks preceding calving, the udder is filling, and one of the things that might be seen is the loss of the cervical plug. This is a very thick tenacious, mucous material hanging from the vulva. It may be seen pooling behind the cow when she is lying down.  Some people mistakenly think this happens immediately before calving, but in fact this can be seen weeks before parturition, and therefore, is only another sign that the calving season is here.

The immediate signs that usually occur within 24 hours of calving would be relaxation of the pelvic ligaments and strutting of the teats. These can be fairly dependable for the owner that watches his cows several times a day during the calving season. The casual observer who is knowledgeable of the signs but sees the herd infrequently cannot accurately predict calving  time from these signs. The relaxation of the pelvic ligaments really cannot be observed in fat cows, (body condition score 7 or greater). However, relaxation of the ligaments can be seen very clearly in thin or moderate body condition cows and can be a clue of parturition within the next 12 – 24 hours. 

These changes are signs the producer or herdsman can use to more closely pinpoint calving time. Strutting of the teats is not really very dependable. Some heavy milking cows will have strutting of the teats as much as two or three days before calving and on the other hand, a thin, poor milking cow may calve without strutting of the teats. 

Another thing that might be seen in the immediate 12 hours before calving would be variable behavior such as a cow that does not come up to eat, or a cow that isolates herself into a particular corner of the pasture. However, most of them have few behavioral changes until the parturition process starts. Source: Calving Time Management of Beef Cows and Heifers, OSU Extension Circular E-1006.

“Cow/calf Corner” is a weekly newsletter edited by Dr. Glenn Selk, Extension cattle specialist emeritus at Oklahoma State University with contributions from additional OSU Extension specialists.