Beef Cattle Browsing
Editor: Dr. Stephen Hammack, Professor & Extension Beef Cattle Specialist Emeritus
This newsletter is published by Texas AgriLife Extension – Animal Science. Media, feel free to use this information as needed and cite Texas A&M University Beef Cattle Browsing Newsletter, Dr. Steve Hammack.
CALF PERFORMANCE FROM SIX BREEDS
USDA-ARS, El Reno, OK, and Oklahoma State University researchers collaborated in using 246 registered Brangus cows managed on either native rangeland or improved pasture to evaluate calf performance from six sire breeds. From 17 to 25 AI sires were used per breed. Results were:
|Sire Breed||Birth Weight||Weaning Weight*||Condition Score#|
*At 205-days of age
#At weaning, scale of 1=emaciated to 9=grossly obese
+Since all dams were also Brangus, heterosis in calves by the other sire breeds might have resulted in slightly higher calf weights for those breeds relative to the Brangus-sired calves.
Birth weights were heavier from mature cows, especially on native pasture. Charolais-sired calves were almost two inches taller at the hip at weaning than Romosinuano-sired, with the others being intermediate. Weaning weights averaged 14 lb heavier on native pasture, but with little difference for Charolais- and Gelbvieh-sired. Calf condition scores were higher on native pasture, except for Charolais- and Gelbvieh-sired. In this study, the Continental sire breeds, particularly Charolais, had an advantage in weaning weight, especially compared to the Romosinuano which is generally known as a genetically smaller breed. Calving difficulty was not reported in this study. The higher birth weight of Charolais-sired calves could possibly cause more calving problems, especially in first-calf heifers. (Prof. Anim. Sci. 24:67)
CAN AN ANIMALS FEELINGS BE MEASURED?
Much discussion continues on animal welfare or well-being. Some say well-being depends on how an animal feels. However, a University of Illinois researcher concludes that feelings (anxiety, fear, frustration, and pain) can not be measured directly, objectively, and scientifically. Instead, he recommends that performance levels, which can be effectively measured, be used to indicate well-being. His proposal is: “for a constitutionally fit animal the best single set of measurable indicators of an animal’s state of being will be its rates of productive and reproductive performance relative to its predicted potential to perform.” So, if the animal performs acceptably it probably feels okay. (Prof. Animal Sci. 23:573)
INTENSIVE EARLY GRAZING OF GROWING CATTLE ON RANGELAND
Grazing stockers on summer range has long been practiced in the U. S. Historically, cattle were put out about as soon as grass was growing well and grazed for the rest of the growing season. Later, especially in areas such as the Flint Hills of eastern Kansas, some rangeland has been double-stocked for the first half or so of the growing season after which all cattle are removed. This has generally resulted in higher total beef production per acre.
In western Kansas, where rainfall averages less than in the Flint Hills, Kansas State University researchers evaluated this system over six years in the 1980s but found that total production for early double-stocking (May 1 to July 15) was not higher compared to normal-stocked season-long grazing (May 1 to October 1). Then for four years they double-stocked early and removed half of the cattle at mid-season. Animal performance was reduced, especially season-long. Finally, from 2002 to 2007 they early stocked at 1.6 times the season-long rate and removed the heaviest animals at mid-season, reducing to normal-grazed numbers for the rest of the season. That resulted in about one-fourth more total beef production per acre and almost $10/acre higher net income, compared to normal stocking for the whole season. Intensive early-season grazing offers potential, but the best system probably will not be the same in different regions. (Kansas State Beef Tips, March, 2008www.asi.ksu.edu/beeftips)
FORAGE AVAILABILITY vs. ANIMAL PERFORMANCE
Over two years, University of Missouri researchers allocated fall-calving cow-calf pairs stockpiled fescue at rates of 2.25, 3.00, 3.75, or 4.50 percent of body weight from early December to late February (phase 1). Crude protein content of the stockpiled forage was 12 to 13 percent in both years. After phase 1, all groups were combined until weaning in early April (phase 2) and continued until mid-July (phase 3). In both years during phase 1, cows in the 4.50 group consumed about 30% more forage than those in the 2.25 group. Pasture utilization ranged from 84% for the 2.25 group to 59% for the 4.50 group. Body weight loss during phase 1 increased as forage allocation decreased, by about twice as much in the first year compared to the second year. But by the end of phase 3, average body weight of cows in the four groups did not differ in either year.
During phase 1 (about the last three months before weaning) calf gain per head increased as forage allocation increased, ranging from 1.48 lb/day for the 2.25 group to 1.75 lb/day for the 4.50 group. However, the opposite was true for calf gain per acre, ranging from 83 lb/acre for the 4.50 group to 130 lb/acre for the 2.25 group. The authors concluded that, of the four levels of forage availability in this study, the higher rate of stocking likely was optimal, since cow body condition was easily regained and production per acre was maximized. In general, economics favors higher levels of forage utilization, without high input costs, but utilization not so high as to damage the long-term integrity of the forage resource. (J. Animal Sci. 86:780)
COST OF GAIN vs. COST OF CATTLE
Current total cost of feedlot gain is about equal to the live price for finished cattle, so the breakeven price for feeder cattle is about that same price. When this is true, for feeding to be profitable the price of feeders must be less than that of finished cattle. We might get to that point.
E. COLI vs. GRAIN PROCESSING, FECAL STARCH, & FECAL pH
Concerns continue with contamination of food by toxin-producing Escherichia coli, specifically E. coli O157:H7. There has been some indication that certain diets might increase shedding of E. coli by fed cattle. Kansas State University researchers fed dry-rolled corn (DR) to steers and found that fecal samples positive for E. coli O157 contained 21% more fecal starch. In a second study, heifers were stepped up to a high DR ration and then sampled after 14 days. At that time, one-third of heifers’ fecal samples were positive. This group of heifers was then divided for individual feeding, with half remaining on DR and half adjusted to SF. The SF group tended to have more heifers with positive fecal samples. Heifers fed DR had higher fecal starch levels and lower fecal pH. But there was no relationship between either fecal starch or pH and prevalence of E. coli 157. (J. Animal Sci. 86:632)
IS THE CATTLE CYCLE GONE?
Some people think maybe so, due to such things as cost of land/energy/feed and some continuing droughts. The same was said in the early 1970s. Back then, some predicted that the advent of large-scale specialized commercial feedyards would eliminate the cycle of high and low cattle numbers that had been occurring over about 10-year periods. The theory was that previous cattle feeding, done largely by individual farmers feeding up whatever grain they produced in a year, led to cyclical effects. The new yards, which were designed to feed large numbers of cattle all the time, would break the old cycle. Cattle numbers reached all-time highs in 1975 (and have never got that high since), the market cratered, and the cycles continued. Will new factors change that? Time will tell.