Beef Cattle Browsing
Editor: Dr. Stephen Hammack, Professor & Extension Beef Cattle Specialist Emeritus
November 2005
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.
RIBEYE STEAKS – WHAT DOES THE CONSUMER WANT?
South Dakota researchers investigated the effect of size of ribeye steaks on consumer choice. Five different sizes of steaks were placed in a retail meat case. All steaks were 1.0 in thick, aged for 10 days. Average ribeye size/steak weight were: 10.7 sq in/0.54 lb; 11.8 sq in/0.65 lb; 13.5 sq in/0.70 lb; 15.3 sq in/0.76 lb; 17.0 sq in/0.78 lb. As reported in the 2000 National Beef Quality Audit, these represent the following percentages of the U.S. fed beef harvest: 5%; 27%; 43%; 21%; and 4%. Consumer preference was based on how long steaks remained in the case before being purchased. There was no significant difference among steak sizes in consumer preference; there was a slight tendency for larger steaks to be preferred. Consumers 30 to 45 years old purchased larger steaks than younger or older buyers. Steaks cut from the middle and rear (closest to the loin) of the boneless rib roll were preferred. In a second trial, comparisons were made between average steaks (13.2 sq in), large steaks (17.3 sq in), and large steaks cut in two portions. Steaks were auctioned to a group of 75 consumers. Buyers paid an average of $0.68/lb more for large over average steaks, but discounted large steaks cut in half by $0.46/lb compared to average steaks. Note: South Dakota consumers may or may not be representative of other areas. (J. Animal Sci. 83:2598)
EFFECTS OF ROTATION GRAZING OF TAME PASTURES
Arkansas researchers evaluated, over three years, fall-calving pairs (of primarily Angus genetics) managed on fescue overseeded with clover, lespedeza, and crabgrass. Fescue hay was offered if dictated by reduced forage density, and a corn-soybean meal supplement was provided during the breeding season. Calves were weaned in either mid April (A, average age of 189 days) or early June (J, average age of 243 days). A calves were backgrounded in drylot for 3 weeks and then grazed on bermudagrass until the J calves were weaned. Pairs were rotated among paddocks either twice monthly (M) or twice weekly (W). Rotation frequency did not significantly affect cow weight, hay consumed, milk production, calving interval, calf birth weight, actual weaning weight, or 205- day adjusted weight. M Cows were significantly higher (0.3 units) in Body Condition Score at breeding. J calves weighed significantly more than A (by 130 lb) at weaning, and in mid-June (by 74 lb). However, 205-day adjusted weight did not differ among A and J calves. Finally, rotation time and weaning date had no significant effect on forage quality or forage species composition. (J. Animal Sci. 83: 2684)
SELECTION EMPHASIS IN TERMINAL SIRES – WHERE SHOULD IT BE?
In a continuous breeding system (replacement heifers saved from within the herd) featuring retained ownership of calves and selling on a carcass grid, it has been found that reproduction is the most economically important trait, followed by production (weight gain), and then product (carcass). Researchers at the Miles City, Montana USDA station wanted to know what the selection emphasis should be for sires in a terminal cross breeding system. They evaluated five sire breeds in a terminal cross using a computer simulation. Breed averages were taken from extensive studies conducted by the USDA Meat Animal Research Center, Clay Center, Nebraska. Traits included were calf survival rate, weaning weight, feedlot gain and feed consumption, dressing percent, marbling score, and USDA Yield Grade. In general, it was found that sire selection emphasis among these traits should be rather uniformly applied, except that feedlot gain and Yield Grade should be somewhat de-emphasized. It should be noted that, in selection of terminal sires, fertility of females is not relevant, since heifers are not kept for breeding in a terminal system. However, in selection of sires to produce females used in a terminal cross, female fertility is an important factor. (Proc. 2005 Beef Improvement Federation Research Symposium)
RESTRICTED HAY FEEDING TO COWS
In some areas, cows are wintered essentially with free-choice feeding of hay. Such feeding often wastes hay, can result in over consumption, and may increase manure output. Illinois researchers studied limit feeding of Simmental-cross cows in three trials. Hay used in the three trials was legume-grass mix averaging approximately 13% to 17% crude protein. In Trial I, lactating cows were allowed access to round bales for 24, 8, or 4 hours/day. Longer access to hay increased manure production, increased hay consumed, increased hay waste, reduced loss of Body Condition Score, and tended to reduce loss of cow weight, but did not affect milk production or calf weight. In Trial II, dry, bred cows were allowed access for 7, 5, or 3 h/d and a fourth group was fed ground hay at 90% of estimated nutritional requirement. Longer access reduced loss of cow weight, increased hay consumed, tended to increase manure produced, but did not affect hay waste. Feeding at 90% was intermediate in hay consumed and hay waste. In Trial III, lactating cows were fed ground hay at 80%, 90%, or 100% of requirement. Level of feeding had no significant effect on any cow or calf factors. It appears that limit feeding of hay may reduce feed cost without reducing production. (Prof. Anim. Sci. 21:182)
EFFECT OF HAULING ON IMMUNE STATUS
Australian researchers used yearling Bos indicus steers to study effects of hauling on the immune system. Steers had been vaccinated 8 weeks before hauling for five types of clostridial organisms. Steers were hauled over paved roads for 72 hours with no rest stop for 3570 miles (approximately equivalent to a haul from Miami to Seattle). Blood analyses were made 2 days before, immediately after, and 6 days after hauling. Some immune system indicators were significantly lower immediately after hauling, but recovered after 6 days. So, the authors noted that the cattle may have been vulnerable to infection during that recovery period. (J. Animal Sci. 83:2632)
“FLUSHING” HEIFERS
Developing heifers to breed at 13-15 months can be costly. Oklahoma researchers wondered if heifers could be developed slowly after weaning and then fed at a high rate just before breeding. They also wanted to look at different energy sources for this purpose. Heifers used were Hereford or Angus X Hereford. In Trial I, treatments were: 42% CP soybean meal (control, C); high starch (high in corn) for 60 day days before breeding (HS-60); high starch for 30 days before breeding (HS-30); and low starch (less corn, more corn distillers dried grains) for 30 days before breeding (LS-30). HS-60 and LS-30 were heavier at breeding. More HS-60 reached puberty before breeding. HS-60 were 24 and 22 days younger at puberty than LS-30 and C. In Trial II, treatments were: C as above; HS-60 as above; LS-60 (high in distillers grains and soybean hulls). At puberty, weight did not differ among the three groups, but HS-60 and LS-60 were younger than C. Incidence of puberty during breeding was higher for HS-60 than LS-60. The authors concluded that high concentrate feeding before breeding may stimulate puberty, especially by using high-starch feeds, but that a minimum of 60 days feeding may be needed. (J. Animal Sci. 83:2653)