Are Your Cows Too Large?

Weekly, Oklahoma State University Extension Beef Cattle Nutrition Specialist Paul Beck offers his expertise on the beef cattle industry. This is a part of the weekly series known as the “Cow-Calf Corner.” Today, he talks about how mature cow weight can impact a producer’s operation.

From the 2012 Ag Census to the 2017 Ag Census, the number of beef farms decreased by 3.9% but cow numbers slightly increased. The consolidation was  from a 5% reduction in small ranches (1 to 100 cows), but 6% increases in medium ranches with 100 to 500  cows and 1% increase in large ranches with 500 or more cows. We will get to see what impact the recent droughts had on consolidation of cattle farms with the release of the 2022 Ag Census in mid February.  

 There are several barriers for young or new farmers entering beef cattle operations, these include high cost of land and equipment and relatively low returns on investment. The average annual cost per breeding female increased to over $1000 dollars per cow in 2022 and have remained at that level. The recent good calf prices have resulted in positive returns over cash costs for the last few years for cow-calf producers.   

These numbers should grab your attention, because I don’t believe the costs and returns can be much different across the regions where beef cows are produced. The costs of maintaining a beef cow and the unit cost of production of weaned calves have increased tremendously over the past 5 years. Variable costs such as fuel, fertilizer and herbicides have been blamed as the primary culprits; however, fixed costs such as equipment, hired labor, and land have increased as well. When cattle numbers rebound, and they always do, will these high calf prices remain stable enough to cover these high costs of production? 

Additionally, cow carrying costs have increased because of a 30% increase in cow size over the last 30 years from 1,047 pounds in the mid 1970’s to 1,369 pounds in the mid 2000’s, and this trend appears to have continued.  A 30% larger cow requires 22% more energy per day for maintenance and will consume 20 to 30% more forage per day, decreasing cow carrying capacity of the farm or increasing input costs associated with pasture management, supplementation, and stored forages. Smaller cows also have been shown to have greater weaning efficiency (lbs of calf weaned per lb of cow body weight). 

 The increased cow mature weight equates to an increase in stocking rate if cows numbers are not adjusted. As stocking rate increases we know that weaning weights and rebreeding rates decrease. This has been linked to reductions in forage allowance (lbs of forage available/ lb animal body weight) limiting diet selectivity, diet quality, dry matter intake, and forage regrowth rate. Total weaning weight/acre has been shown to increase up to a point even though individual animal is decreased; until animal performance is reduced to such an extent that weaning weight/acre begins to decrease.  

In research on introduced warm season grasses in the Southeastern U.S. (Beck and others, 2016; doi:10.2527/jas2015-0049) cow-calf pairs were separated into heavy (weighing 1,220 lb) and light (weighing 970 lbs) cow size groups and stocked on pastures 2.5, 1.7, 1.2, and 1 acres per cow unit over 4 years. These pastures were fertilized with 100 lbs of nitrogen per acre over the summer. 

Heavy cows weaned calves than light cows, but the increase was only 19 lbs heavier weaning weight for every 100 pound increase in cow mature weight. Larger cows also lost more weight and body condition than smaller cows.  Weaning efficiency ratios of smaller cows were higher (0.49 lbs of calf weaned per lb of cow for small cows vs. 0.42 for large cows).  As stocking rate increased, lbs of calf weaned per acre increased from 130 lbs at the lightest stocking rate to 411 at the heaviest stocking rate.  

The increase in weight and condition loss with larger cows is a concern and this could lead to reduction in fertility and increases in rebreeding interval for large cows, especially those with higher stocking rates. Because hay was fed when needed and cows were supplemented to maintain appropriate body condition, rebreeding rates were not affected. But, as cow mature weight and stocking rate increased the amount of hay and annual cow costs increased as well.  Increasing stocking rate reduces individual calf body weigh gain but increases total calf gain per acre.  

For the larger cows, any advantage in calf weaning weight was diminished during 2 year long periods of drought while this research was conducted, but were enhanced  during periods of normal rainfall. These responses to drought indicate production systems with higher stocking rates and larger cows are more impacted by climatic stressors and thus less resilient to harsh environments.  

Verified by MonsterInsights