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.
Editor: Dr. Stephen Hammack, Professor & Extension Beef Cattle Specialist Emeritus
2011 National Beef Quality Audit
The first National Beef Quality Audit of fed cattle was conducted in 1991, with subsequent audits in 1995, 2000, and 2005. Findings of the 2011 audit have been reported by the National Cattleman’s Beef Association. The audit was conducted in three phases: Phase I to evaluate how different segments of beef production view quality, Phase II to assess current status of quality, and Phase III to determine how producers are implementing principles of Beef Quality Assurance.
Phase I revealed that industry segments often use different terms to define beef quality, which hinders communication between segments. Consumers want to know more about how beef is raised and its origin. Food safety is paramount to packers, food service, and retailers. Beef is generally recognized as being safe and of high quality, but the entire industry should continuously strive for improvement. Packers, food service, and retailers are under pressure to ensure consumers that animals are treated humanely. The industry should improve communication with the public.
In Phase II, it was found that almost all animals arriving at the packer have identification; 86 % had visual lot tags applied by the feedyard and 51% had some individual identification. Carcass trait averages (and ranges) were as follows:
- hot weight 825 lb (310 to 1203)
- fat thickness 0.5 in (0 to 1.6)
- ribeye area 13.8 sq in (7.8 to 23.0)
- marbling score Small40 (Practically Devoid100 to Abundant60)
The percent of Choice and Prime had been 50-55% in the previous four audits but increased to 61% in 2011. Instrument grading has become common; it was found to result in about 3% higher percent Choice-Prime than visual grading. Carcass weight has increased; almost 95% of carcasses weighed within 600-1000 lb, the range within which price is generally not discounted. However, about one-fourth of ribeyes were outside the generally preferred range of 12-16 sq. in, most outliers being too large. Some 13-14% of carcasses qualified for branded programs which require quality grades of upper 2/3 Choice or higher, such as Certified Angus Beef. Percentage of black-hided cattle increased from 45% to 61%.
In Phase III surveys, almost 80% of producers said they use individual animal id to track health treatments, ranging from 62% for stocker operators to 89% for seedstock. About 90% of producers said they had a working relationship with a veterinarian, but about 25% said they would use medications off label without veterinarian approval. Almost nobody reported still using electric prods as their primary means of handling cattle; more than 40% of producers use prods less than 10% of the time.
When how asked how they intentionally influenced quality of the product, proper animal handling and preventative health procedures ranked highest, followed by nutrition and implementing best management practices such as method of administering vaccines and antibiotics. It appears that producers are implementing principles of Beef Quality Assurance but some education is still needed. Seedstock and cow/calf producers ranked genetics high, but backgrounder/preconditioners, stocker/yearling operators, and feeders did not. Overall, the survey ranked quality challenges, in decreasing order of importance, as being food safety, eating satisfaction, how and where cattle are raised, percent lean-fat-bone, weight and cut size, and genetics. (http://www.bqa.org/CMDocs/bqa/NBQA.pdf)
A MATURITY INDEX TO ESTIMATE BREEDING READINESS AND PROFITABILITY IN HEIFERS
For a good many years, it has been recommended that heifers be developed to breeding to weigh 60-65% of estimated mature weight to insure high levels of first-breeding reproductive performance. Recent research with British-Continental types has indicated that a lower percentage of weight may be optimum, considering both biological and economic factors. Estimation of a heifer’s percentage of mature weight is often based on the average mature weight of the whole herd.
A study was conducted to investigate possibilities of improving on use of that average. A maturity index (MI) was developed which included, in order of predictive importance, pre-breeding weight, birth weight, age, and dam weight. MI was found to be more accurate than basing percentage of mature weight on herd-average mature weight. The authors concluded that heifers of “relatively older age, smaller birth weight, smaller dam weight, and higher pre-breeding weight fed at higher nutritional levels would have a relatively higher maturity index and thereby a greater probability of becoming pregnant.” (2009 Univ. of Nebraska Beef Report, p. 15)
In more recent reports, MI was compared to revenue, cost, and profit. Higher MI was associated with higher cost. Highest profit occurred at MI slightly below the MI producing highest gross revenue. The economically optimum MI was 61.3 (a heifer weighing 61.3% of her own mature weight at 15 months of age); however, that resulted from a nutritional level producing a heifer weighing 53% of herd-average mature weight, not of the heifer’s own mature weight.
Some interesting interactions were found. Restricting nutrition to younger heifers out of larger dams reduced profit. Conversely, high nutrition to older heifers out of smaller dams also reduced profit. The authors suggested that “when managing in groups, decision makers should either select like animals that match the management regime or the management regimes should be adjusted to match the animals selected.” (2012 Univ. of Nebraska Beef Report, p. 41 and p. 43)
EFFECT OF CASTRATION TECHNIQUE ON PERFORMANCE
Calves averaging 200 days of age and 471 lbs were allotted to one of five groups:
- castrated surgically using an emasculator
- castrated with a Callicrate Bander
- castrated surgically with a Henderson Castrating Tool
- left intact as bulls
- castrated surgically at 52 days of age (controls)
After 14 days, calves castrated earlier at 52 days of age and intact bulls had gained significantly more than the other groups, among which there was no significant difference. However, by 84 days, when the study was concluded, there was no significant difference among all groups in gain, nor in daily feed intake, daily water intake, gain:feed ratio, or residual feed intake. Surgical castration at the start of the study resulted in a short-term inflammatory response and banding resulted in a delayed response. NOTE: Other research has shown that pain due to castration is more acute and lasts longer as age, weight, and testicular size increase, so early castration is more humane and is strongly recommended as a part of Beef Quality Assurance. (J. Animal Sci. 90:2345; Univ. of Florida)
RELATIONSHIP BETWEEN IMPLANT PROTOCOL AND GENETIC MARKERS
Eight contemporary groups of steers or heifers were used in this study. Among groups of calves lighter at weaning, half of the calves received a low-level grower implant (Revalor G ®). Approximately 75 days later, when all calves were placed on feed, those receiving the grower implant were implanted with an aggressive finisher implant (Synovex Plus ®). Approximately 100 days later those calves received another aggressive implant and calves that had never been implanted received a milder finisher implant (Revalor IS ® or Revalor IH ®). Heavier groups received the same treatments, except none received a grower implant.
Compared to the mild implant protocol, the aggressive protocol significantly increased growing ADG and ADG to final implant (but not overall ADG), weight at time of last implanting (but not final weight), and ribeye area. The aggressive protocol significantly decreased fat thickness, numerical Yield Grade, marbling score, and tenderness. There was no significant difference in carcass weight or dressing percent.
Across both mild and aggressive protocols, 8 of 9 previously-identified growth genetic markers were positively related to ADG and weight; 6 of 17 previously-identified tenderness markers were positively related to shear-force tenderness. Growth markers were related to increases in carcass yield traits but decreased tenderness; favorable tenderness markers were related to decreased ADG and weight. There was some indication that some growth markers increased the effect of aggressive implanting; conversely, the effect of some tenderness markers was reduced by aggressive implanting. The authors concluded that genetic markers might be used to manage, but not eliminate, undesirable effects of growth implants on beef quality. (J. Animal Sci. 90:2410; U. S. Meat Animal Res. Ctr.)
EFFECT OF VITAMINS A AND D ON PERFORMANCE AND CARCASS
A group of 168 Angus-crossbred steers initially averaging 625 lb were fed Vitamin A, Vitamin D, both Vitamin A and D, or neither. There were no significant differences in feed consumption, ADG, feed efficiency, or sickness. Controls had higher fat thickness and numerical Yield Grade. Rations without Vitamin A resulted in higher marbling scores and Quality Grade. (J. Animal Sci. 90:1866; Ohio St. Univ.)
INCREASED RESIDUE TESTING OF MEAT, POULTRY AND EGGS
The USDA Food Safety and Inspection Service plans to increase residue testing of meat, poultry, and eggs. Up to now, testing has been for one chemical at a time. Under the proposal, as many as 55 pesticide chemicals, 9 kinds of antibiotics (approved and unapproved), various metals, and eventually over 50 other chemicals will be tested on a single sample using multi-residue methods. Industry groups have expressed support of this change in order to reassure consumers of product safety. (http://www.fsis.usda.gov/News_&_Events/NR_070212_02/index.asp).