Editor: Dr. Stephen Hammack, Professor & Extension Beef Cattle Specialist Emeritus
Beef Cattle Browsing is an electronic newsletter published by Texas A&M AgriLife Extension, Department of Animal Science at Texas A&M University. This newsletter is a free service and is available to anyone interested in beef cattle. Media, feel free to use this information as needed and cite Texas A&M University Beef Cattle Browsing Newsletter, Dr. Steve Hammack.
NEWLY – IDENTIFIED GENETIC ABNORMALITY IN ANGUS
Polymelia, also being referred to as developmental duplication or DD, a condition characterized by calves born with extra limbs, has been reported in American Angus cattle; it has been identified as being due to simple genetic recessive inheritance, likely involving a recent mutation. Approximately 6 percent of American Angus sires are estimated to be carriers of the responsible gene. Occurrence of the condition at birth is much lower than would be predicted from the estimated gene frequency in the breed. Therefore, in most cases embryonic death apparently occurs. Additional information can be accessed at http://www.angus.org/Pub/DD/DDInfo.aspx.
A recent presentation at the Beef Improvement Federation Annual Meeting and Research Symposium noted that all breeds have numerous mutations but that most are not problematic. Inbreeding or linebreeding increases the chance that undesirable recessives are inherited from both parents. Outbreeding within a breed decreases that chance and crossbreeding eliminates it, unless the breeds involved in the cross have some common background in their creation. (www.beefimprovement.org)
TIMING OF PROSTAGLANDIN ADMINISTRATION IN TIMED AI
A study was conducted using 2465 British or British-Continental postpartum cows in 13 herds located in 8 states. Within-herd averages ranged from 3.6 to 5.9 years of age, 4.5 to 5.9 Body Condition Score, and 53 to 88 days postpartum. All cows were subjected to the CO-Synch + CIDR protocol with one of the following prostaglandin F2α (PGF) alternatives:
- 2 doses PGF (25 mg/dose) 8 hours apart, first dose at CIDR removal (2P8);
- 2 doses PGF (25 mg/dose) in two injection sites at CIDR removal (2P);
- 1 dose PGF (25 mg/dose) at CIDR removal (1P).
All cows were AIed 72 hours after CIDR removal. In five herds, any cows returning to estrus were AIed again; in eight herds cleanup bulls were used. Fixed-time AI pregnancy rates were significantly higher for 2P8 (55%) than 1P (48%) with 2P (51%) not significantly different from 2P8 or 1P. Rates were significantly higher for cycling cows and for those 3 years old or older. Overall pregnancy rates did not significantly differ among the three groups but was significantly higher in cows 3 years old or older.
Since the 2P procedure did not significantly increase fixed-time pregnancy over 1P and the 2P would have higher treatment cost, there would be no advantage for 2P. The 2P8 procedure could be advantageous over 1P if the higher fixed-time pregnancy rate was worth more than the extra treatment and labor cost of 2P8.
(J. Animal Sci. 90:4814; Univ. of Minnesota, Colorado St. Univ., Univ. of Wyoming, Ohio St. Univ., Virginia Tech Univ., Purdue Univ., Kansas St. Univ., Univ. of Florida, Univ. of Wisconsin)
EFFECT OF BALE FEEDER TYPE AND MONENSIN ON PERFORMANCE OF WINTERING COWS
Cows initially averaging 1087 lb and 5.2 Body Condition Score were fed 3 lb/day of a 36% CP cottonseed meal-based pellet either with or without 200 mg/hd monensin (Rumensin®). Across both supplements, the four types of round-bale hay feeders used (and the resulting percentages of hay loss) were:
- conventional open-bottom steel ring (20.6%)
- sheeted-bottom steel ring (12.7%)
- polyethylene-pipe ring (21.5%)
- modified-cone feeder (5.6%)
Monensin supplementation significantly improved weight gain, condition score change, and final body condition. The authors concluded using a modified-cone feeder and supplementing with monensin improved performance and reduced cost.
(J. Animal Sci. 91 E-Supple. 1:4; Oklahoma St. Univ., USDA-ARS at El Reno, OK.)
WHAT DO MOTHERS THINK ABOUT FOOD FOR THEIR FAMILIES ?
In a recent “Gate to Plate” survey, more than one thousand American mothers were surveyed regarding where food comes from and how it is raised. Some of the results:
- more than half of respondents indicated they believe it is important to feed hormone-free products, even at higher cost
- more than half thought it is important to buy “all natural” if possible, because it is more nutritious
- 7 out of 10 thought the family farm is dying
- 7 out of 10 thought farmers are an important source for information on food and farming, but only 1 out of 5 sought out farmers for such information
(http://findourcommonground.com/)
EFFECT OF MANAGEMENT FACTORS ON SALE PRICE
Effects on price of group selling, fill, condition, and health were evaluated at 10 weekly auctions in 2000, 2005, and 2010, with 137,894 individual calves in the analysis. Results were:
- percentage of calves sold as singles decreased over time
- discounts for single sales decreased over time
- discounts for full or “tanked” calves increased in later years
- both very thin and fat calves were discounted
- calves that were visibly sick, stale, or had dead hair coats were discounted
- preconditioned calves received premiums
The authors concluded that highest prices were received for average flesh, average fill, healthy, preconditioned calves sold in groups.
(J. Anim. Sci., 91 E-Supple 1-24; Univ. of Arkansas)
TIMING OF BVD VACCINATION VS. RESPONSE
A group of 1004 male and female fall- or spring-born Angus calves born in three consecutive years were used in this study. Calves were vaccinated with a modified live product containing antigens against infectious bovine rhinotracheitis (IBR), bovine respiratory syncytial virus (BRSV), parainfluenza-3 (PI-3), and bovine viral diarrhea virus types 1 and 2 (BVDV1 and BVDV2). An initial vaccine was given, followed three weeks later by a booster vaccination. No calves testing positive for BVD persistent infection were in the study. At time of first vaccination, fall-born calves averaged 107 days of age and 271 lb; spring-born averaged 149 days and 359 lb.
Half of the calves were weaned at initial vaccination and half weaned at the booster vaccination. To measure antibody levels, blood serum was collected 3 weeks before initial vaccination, at initial vaccination, at booster vaccination, and 3 weeks after booster vaccination. Antibody levels were higher as age of dam increased. The level of maternal antibodies present at the time of vaccination reduced initial, booster, and overall antibody responses to vaccination. Calves weaned at initial vaccination had greater final antibody level, initial response, and overall response to vaccination than animals weaned at booster vaccination.
The authors concluded that 1) calves from younger cows need to be vaccinated at an earlier date, 2) older calves need to be vaccinated at an earlier date than younger calves, and 3) if weaning and vaccination are done at the same time calves should receive the initial vaccination when they are weaned.
(J. Animal Sci. 91:4440; Iowa St. Univ., Massey Univ. of New Zealand)
EFFECT OF VITAMIN C IN DISTILLERS GRAINS RATIONS
Ethanol coproducts such as dried distillers grains (DDGS) are being widely used where available for finishing cattle. Such products often have elevated levels of sulfur, which can adversely affect performance and therefore limits their use. Previous research indicated that Vitamin C aids in clearance of sulfur metabolites from the body.
A group of 120 Angus-cross steers initially averaging 751 lb were fed rations differing in levels of DDGS/sulfur and with or without Vitamin C for 149 days. As sulfur level increased, there were significant decreases in feed consumption, ADG, final weight, carcass weight, fat thickness, numerical Yield Grade, and marbling score. Adding Vitamin C to the highest sulfur-level ration resulted in increased fat thickness, marbling scores, and percent grading Choice. The authors concluded that, in rations with high levels of sulfur, supplementing Vitamin C can improve feeding performance and carcass quality. (J. Animal Sci. 91:4303; Iowa St. Univ.)
HOW BIG IS A STEAK TODAY?
In the latest National Beef Quality Audit the average ribeye measured 13.7 sq in. That results in an inch-thick steak weighing 15-17 ounces. Most ribeyes fall in the range of 11-16 sq in, though some are much smaller and some much larger. A ribeye measuring 11 sq in should result in a steak weighing 12-14 ounces; the 16 sq in ribeye steak should weigh about 18-20 ounces. Many consumers don’t want more than the 12-14 ounce steak, not to mention the bigger ones. In fact, a staple item at many mid-price steak houses is a 6 or 8 ounce portion.
Reducing thickness reduces weight, but also generally reduces eating satisfaction when grilling, especially in the hands of inexperienced or poorly informed cooks. In some cases, large cuts consisting of multiple muscles are being separated into the component muscles; this also can have the added benefit of being able to trim any outside fat from the fabricated muscles. And some steaks are being cut in half or even smaller portions. Cattle weights show no sign of declining, or even stabilizing, so the industry will probably just have to develop more and better ways to use larger cattle.