The Cattle Show & Ag Lifestyles

By:

Bryan McMurry, Ph.D.

Economies of scale are an important consideration for any business and can lead to greater profitability. However if that greater scale principle is applied to individual cow weights on the ranch we quickly find out that bigger is not better.

Variation in individual cow weights in the U.S. is up to 1,000 pounds. It is not uncommon to see variation of this magnitude in any given herd, even relatively small herds. Kris Ringwall of North Dakota State University recently reported in Beef Talk that the mature weight of 102 cows in two herds at the Dickinson Research Extension Center in Dickenson, ND ranged from 856 to 1935 pounds. These cattle are actually in two herds with average weights of 1216 and 1571 pounds, respectively and are likely representative in size of not only cattle in North Dakota but the entire U.S.

Dr. John Paterson found similar magnitude in the variation in cow size among the Montana ranches participating in the Montana Beef Network. One of the ranches we visited near Big Timber had an average cow weight of well over 1300 pounds. The heaviest cow was just over 1900 pounds. To their surprise when they weaned her calf it weighed 305 pounds. That is not a heavy enough calf to pay that cow’s winter-feeding bill let alone the entirety of her annual expenses. Not surprisingly the ranch manager punched her ticket for a trip on the first truckload of cull cows to the cow processor. Frankly we have countless cows across the U.S. that are high-cost and inefficient that need to be removed the production system.

If the objective of our cow/calf operation is to produce a calf that weighs between 550 and 650 pounds at 7 months of age of a quality and type to fit into our growing and finishing systems as economically as possible, then how does mature weight of the cow impact that objective? One would logically expect that larger cows are more capable of producing large calves than small cows, but at what cost?