CORN – HOW MUCH GOES TO BEEF ?
We often see statements about how much corn cattle eat to produce beef and how much better the world would be if that corn went directly to humans. Just how much of U. S. corn production actually goes to beef cattle? Of the total domestic use of corn, 11.3% is used by beef cattle. Some corn is exported so, of total U. S. corn production, 9.4% is used by beef cattle. Even when combined, beef, dairy, pork, and poultry account for 44.9% of total domestic use of corn and 36.4% of total U. S. corn production.
(USDA Feed Grain Database and Agricultural Marketing Resource Center, 12/19/14)
PREDICTING FEEDING PERFORMANCE FROM GENOMICS
Data were analyzed from 5,353 head from six commercial feedlots. At placement, animals were weighed and hair samples were collected. DNA was analyzed to calculate molecular breeding values for days on feed, average daily gain, hot carcass weight, yield grade, rib-eye area, marbling, and tenderness. Subsequently, actual data were collected for those seven traits.
The authors noted the potential for declining costs of testing and the probable development of other genetic markers for traits important in feedlots. But, based on their analyses, the authors concluded “at the present time, the functional value of genetic information at the feedlot stage continues to be the ability to improve the genetic distribution of cattle entering the feedlot and these improvements will need to take place in the industry’s breeding sectors. Note, however, that selecting breeding stock for traits that are valuable in the feedlot sector may or may not be advantageous in other sectors”. The latter consideration could particularly apply to much of the cow-calf sector, especially for producers not retaining ownership beyond weaning.
(From a selected paper presented at the Southern Ag. Econ. Assoc. Annual Meeting, Feb. 2014; Oklahoma St. Univ.)
EFFECT OF STOCKING RATE AND IONOPHORE ON GRAZING PERFORMANCE
A group of 30 Angus X Brahman heifers initially averaging 755 lb was grazed 86 days from late June to mid-September. Over the grazing period, the pasture averaged 7.7% CP and 47.6% digestible organic matter. Heifers were stocked at either 0.7 or 1.0 hd/ac and received 0.9 lb/hd/day of a 14% CP supplement, with free-choice salt-based mineral. One-half of the heifers on each stocking rate received 200mg/day monensin in their supplement.
ADG averaged 1.10 lb /day for the low stocking rate and 0.73 lb/day for high stocked. There was no significant effect of monensin supplementation on ADG at either stocking rate or during any period of grazing. The authors concluded that monensin “may not improve performance of animals receiving low-quality warm-season forages with limited supplementation”. NOTE: Other research has generally shown significant positive effects on performance and economic return from ionophore supplementation, including monensin, especially on higher-quality forage.
(J. Animal Sci. 93:3682; Univ. of Florida, Oregon St. Univ., North Carolina St. Univ, Elanco Animal Health)
WHITE ANGUS ?
You may have seen reference to Ona White Angus recently. In fact, they’re not. Not pure Angus that is. These cattle were developed on the University of Florida Range Cattle Research and Education Center at Ona, Florida (http://rcrec-ona.ifas.ufl.edu/) . The center did not intentionally set out to develop cattle of any particular color. The original research herd was used to compare performance of purebred Angus, Charolais, and Brahman and crosses among those breeds. Later, Simbrah bulls were used and heifers were put back in the herd from that cross; Angus and Brangus bulls followed. Beginning in 2002 some white calves appeared and these were bred to Angus. Additional white colored calves appeared over several years leading to the current Foundation herd of approximately 90 head.
According to Dr. John Arthington, Center Director and Professor of Beef Cattle Management, the cattle are known to be 3/4 Angus with the remaining 1/4 being unknown portions of Angus, Charolais, Brahman, and/or Simmental. The white color is attributed to color dilution factors from Charolais and, probably to a lesser extent, Simmental. According to Dr. Arthington, no intermating has been done within the herd, so any color transmission is not known. Considering the known genetic effect of color dilution genetics, it likely these cattle would not be true breeding for their color.
EVALUATION OF STRIP STEAKS VARYING IN MARBLING AND SOURCE
Strip loins were obtained from cattle of the following designations (with intramuscular fat content shown in parentheses):
- Australian Wagyu (26.6%)
- American Wagyu (18.4%)
- USDA Prime (14.7%)
- USDA Upper 1/3 Choice (9.0%)
- USDA Upper 2/3 Choice, Holstein (8.5%)
- USDA Lower 1/3 Choice (5.6%)
- Grass finished (3.8%)
- USDA Select, Holstein (3.4%)
- USDA Select (3.3%)
- USDA Standard (2.0%)
The Australian Wagyu loins were obtained from an Australian distributor, the American Wagyu from a distributor in Nebraska, the grass finished (from cattle grazed in New Zealand) from a distributor in the U. S., the Holstein from a purveyor in Houston, TX, and the remainder from a processing plant in Omaha, NE. The vacuum-packed loins were aged for 28 days after slaughter (48 days for grass finished). After aging, mechanical shear-force tenderness tests were used to eliminate any steaks tougher than USDA Certified Very Tender in an attempt to minimize effects of tenderness on consumer rating of flavor. A panel of 120 untrained consumers evaluated grilled, one-inch thick steaks for tenderness, juiciness, flavor liking, and overall liking. A highly trained 5-member panel evaluated the steaks for 21 attributes of flavor.
Consumer panel ratings of tenderness, juiciness, flavor liking, and overall liking increased consistently, with few minor exceptions, as IM fat percent increased. The same trend held for percentage of steaks considered acceptable by the panelists for those four categories. There were three general groupings of consumer rating and acceptability; at the top were Australian Wagyu, American Wagyu, and Prime followed by High Choice, Holstein Top Choice, and Low Choice and then grass finished, Holstein Select, Select, and Standard. If there were no undesirable off-flavors present, level of fat had the most influence on flavor acceptability by consumers. Fat-like flavor, as evaluated by the trained panel, was highest for Australian Wagyu, American Wagyu, and Prime.
The authors noted that, even though only samples measured mechanically as very tender were used in the study, consumers tended to rate fatter steaks more tender. They stated, “It is unclear if consumers possess the ability to categorize very tender beef or if superior juiciness and flavor in higher-fat beef influence consumer perception of tenderness”. Regardless, higher marbling equaled higher satisfaction.
(Meat Science 100:24; Texas Tech Univ., Utah St. Univ., Mississippi St. Univ.)
HYPERTENSION IN CATTLE
Congestive heart failure (CHF) in cattle due to pulmonary arterial hypertension (PAP) has long been associated with locations above 7,000 ft elevation. This condition has been called such things as brisket disease, high mountain disease, high elevation disease, dropsy, or big brisket. However, there are anecdotal reports of this condition occurring in feedyards (especially in late-fed, fat cattle) at elevations of as low as 2,500 ft. Researchers wondered if PAP increased during feeding and if individuals with higher PAP at high elevation also had higher PAP after finishing at lower elevation.
153 Angus calves were born in March and April at elevation of 7,100 feet. Cattle with PAP values of 50 mm Hg or higher are considered at risk for CHF; in this herd, heifers with <40 mm Hg are retained for breeding at the location. About one-half of the calves was sired by bulls with <40 mm and one-half by AI sires of unknown PAP value. PAP was evaluated on calves at 4 and 6 months of age at 7,100 ft elevation and at 13 and 18 months of age at 4,250 ft elevation in the feedyard where they were finished.
PAP values increased numerically (but not statistically significantly) from 4 to 6 to 13 months of age. When finishing concluded at 18 months of age, cattle averaged 1377 lb, 31.7% empty body fat, and grading 83% Choice and 10% Prime. At that time, PAP values were significantly higher than earlier averaging 50.3mm, about what is considered a beginning risk for CHF. Calves with highest PAP values at 6 months of age also tended to have highest values at 18 months of age.
(J. Animal Sci. 93:3854; Texas Tech. Uni., Colorado St. Univ.)
WORLD CATTLE NUMBERS
According to the United Nations Food and Agriculture Organization, the most recent data (2013) show 1.468 billion cattle worldwide. Brazil leads with 211.8 million (14.4% of world total), followed by India (189.0 million, 12.9%), China (113.5 million, 7.8%), and the U. S. (89.3 million, 6.1%), giving these four countries over 40% of the world’s total. While the U. S. is only fourth in numbers it is first in total beef production. Rounding out the top 10 in numerical order are Ethiopia, Argentina, Sudan, Pakistan, Mexico, and Australia, but no other country has as much as 4% of the total. There are 104 countries (of 209 listed) with over 1 million head. Greenland is last, with 15 head.
FAT MAY BE OFFICIALLY DECLARED A TASTE
Currently there are five recognized tastes: sweet, sour, salty, bitter, and umami. Umami is a Japanese word roughly translated as savory or meaty. The amino acid glutamate conveys the umami taste. Glutamate is highest in protein foods (especially meat, cheese, fish, milk, and some vegetables) and tends to increase as foods age or ripen. Now, fat has been proposed as a sixth taste. Scientists list five requirements for fat to be recognized as a “taste”:
- there must be a distinct class of effective stimuli (breakdown products of fats and fatty acids;
- there should be chemical receptors (on taste bud cells) to change chemical code to electrical code;
- there must be a neurotransmission of the signal to the brain;
- fat perception must be independent from other tastes and cannot be associated with aroma or texture;
- there must be physiological effects after activation of taste bud cells.
Trained evaluators can distinguish tastes. The proposed name for the taste of fat is oleogustus. It is now up to the scientific community to decide if fat meets the five requirements for an official taste. NOTE: Many gourmet hamburger chefs consider 30%fat/70% lean to be the most flavorful mix. While some health advocates advise eating extra lean (4% fat) ground beef, product below 15% fat tends to be dry and tasteless to most people.
(Taking Stock, American Soc. of Animal Science, 8/10/15)