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.
NO AGE LIMIT FOR BEEF TRADE?
Maybe. As part of the worldwide effort to combat bovine spongiform encephalopathy (BSE), the World Organization for Animal Health (OIE) standards formerly restricted exports and imports to boneless beef from animals less than 30 months of age. OIE recently changed that to remove all age restrictions. But Japan has not accepted even the 30-month standard, implementing 20 months instead. And, at this point, they’re still sticking to that requirement in spite of the fact that OIE has now declared Japan to be controlled-risk for BSE as is the United States. In other words, Japan is restricting beef imports from us on the grounds of BSE prevention even though our BSE status is the same as theirs. (meatingplace.com, 6/2/2009)
EFFECT OF TIME OF VACCINATION AT THE FEEDYARD
A group of 263 steer and bull calves initially averaging 526 lb were obtained from multiple local auctions in western Arkansas and eastern Oklahoma. Four vaccination treatment groups were implemented:
- upon arrival with both clostridial and BRD
- upon arrival with clostridial; BRD 14 days later
- upon arrival with BRD; clostridial 14 days later
- both clostridial and BRD 14 days after arrival
BRD was boostered 14 days after initial vaccination. Measured over 56 days from arrival, ADG and level of sickness did not differ; 69% of all calves were treated with antibiotics at least once. Of calves requiring treatment for BRD, those receiving both vaccinations upon arrival averaged being treated two days earlier than calves receiving both vaccinations 14 days after arrival. There were more chronics (defined as still showing BRD symptoms after three treatments with antibiotic) in the group with upon-arrival clostridial and delayed BRD compared to the group receiving both upon arrival. Otherwise, delayed vaccination did not reduce performance or increase sickness. (Univ. of Arkansas; J. Animal Sci. 87:2409)
EFFECT OF CALF WEANING AGE ON COW PERFORMANCE
A herd of 408 cows (about 2/3 straight Angus and 1/3 Hereford-Charolais cross) were evaluated over three years. Calves were weaned from half of the cows at about 180 days of age (EW) and the other half at about 225 days (NW). There was little difference in body weight of cows at any point, except that EW cows were significantly heavier at normal weaning time. Also, body condition score (BCS) of EW and of older cows was significantly higher both precalving and postcalving. Calving interval of EW and NW did not differ significantly; interval was significantly longer in two-year-olds than threes. Age of cow at the beginning of the study significantly affected reproductive performance. Over 40% of two-year-olds failed to wean a calf in both of the succeeding years of the study, compared to only 15% of cows 6 years old and older. Cows were culled for:
- failure to conceive
- not calving within the designated calving season
- not rearing a calf to weaning
- producing a still-born calf
- low calf weaning weight
- poor BCS at weaning
About one-third more NW cows (45%) were culled than EW cows (34%). Cows whose calves were weaned early produced calves significantly heavier (19 lb) at weaning the next year. The authors concluded that “early weaning improved energy status and production efficiency.” (West Virginia Univ.; J. Animal Sci. 87:2428)
ARE HYBRID CORNS DIFFERENT?
No, at least not for finishing cattle. A group of 475 steers initially averaging 834 lb were fed five commercially-available corn hybrids in both high-moisture and dry-rolled forms. High moisture had greater feed efficiency than dry rolled. However, there were no significant differences among the hybrids in any feeding or animal performance measure. And there was no interaction between hybrid and corn processing method. (Univ. of Nebraska; J. Animal Sci. 87:2323)
ECONOMIC IMPACT ON PREGNANCY TESTING, BULL TESTING AND A SHORTENED BREEDING SEASON
A study was conducted on the economic effects of three management practices in a South Texas beef herd. The study herd consisted of 200 cows and 8 bulls. Three management practices were evaluated over a 10 year period:
- pregnancy testing vs. no testing
- bull BSE (Breeding Soundness Evaluation) vs. no BSE
- 90-day breeding season shortened from 120 days
On a cow per year basis, pregnancy testing cost $6.20 and BSE cost $2.31. Per dollar of cost, pregnancy testing returned $18 and BSE returned $22.To facilitate late-calving cows to re-breed, an extra $780 cost for supplemental feed was incurred for the herd in the first year. For every dollar of that extra feed the return was $13 over the life of the study. (Dept. of Ag. Econ., Texas AgriLife Extension, Texas A&M System; FARM Assistance Focus – June, 2009)
EFFECT OF BODY CONDITION SCORE ON HEIFER PERFORMANCE
Simmental X Angus heifers initially weighing 975 lb were fed to reach Body Condition Score (BCS) of either 5 (MOD) or 7 (FAT), on the BCS scale of 1=emaciated and 10=obese. Heifers were then fed only 30% of calculated energy required for body maintenance until they became anestrous (based on serum progesterone levels). At that point, high-energy feeding resumed until estrous returned (based on two normal cycles as determined by progesterone level).
During energy restriction, FAT heifers were still cyclic for 148 days compared to 61 days for MOD. Both groups averaged about the same in body weight and BCS at anestrous. Upon energy repletion, both groups averaged resuming estrous activity after about 54 days. Near onset of estrous, FAT were significantly heavier and higher in BCS. The authors concluded that “cattle with greater BCS may withstand periods of nutritional stress longer before sacrificing estrous cyclicity.” In other words, if you can put fat on heifers you’ve got some cushion to work with. (Univ. of Minnesota and Univ. of Florida; J. Animal Sci. 87:2255)
ANNUAL BEEF CATTLE SHORT COURSE
The 55th Annual Texas A&M Beef Cattle Short Course is coming up August 3-5 on the campus in College Station. There will be 20 sessions, more than 50 hours of training on current issues and technologies, live animal demonstrations, and a trade show with over 100 exhibitors.
IS NATIONAL ANIMAL ID DEAD?
If not, it’s in intensive care. The U. S. House of Representatives has voted to stop funding the National Animal Identification System on the grounds that voluntary participation has been too low to function effectively in dealing with a national disease outbreak. However, some elected officials favor a mandatory system, so there might still be national ID of some sort. Stay tuned.