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.
COOL IS STILL HERE
The U. S. House of Representatives has passed legislation with some changes from the original Country of Origin Labeling, which started as part of the 2002 Farm Bill. One change is that covered commodities from animals not of U.S. origin may be labeled with “all of the countries in which the animal may have been born, raised, or slaughtered.” Another change deals with ground or blended product, which must be identified by “all countries of origin” or “all reasonably possible countries of origin” of animals from which the product is made.
Regarding records to verify origin, those “maintained in the course of the normal conduct of business, including animal health papers, import or customs documents, or producer affidavit, may serve as such verification” and the Secretary of Agriculture may not require anything more. Product from any animals located in the U. S on January 1, 2008 can be labeled of U. S. origin. After that, documentation will be needed to verify origin. So, it may be a good idea to individually identify animals and maintain applicable production records and affidavits for at least two years. Regulations await further Congressional action. But at this point, barring further action, COOL will go into effect September 30, 2008, either with these changes or as originally passed. (U. S. House of Representatives, H. R. 2419, 7/27/07)
TREATMENT TO REDUCE SHIPPING STRESS
Australian researchers studied the effect of two materials on transported cattle. Bos indicus steers (2 1/2 years old, averaging 706 lb) were treated as follows:
- control (no feed or water for 48 hours)
- transported for 48 hours
- dosed with glycerol (3.2 oz/100 lb body weight) and transported
- dosed with betaine (an organic osmolyte, 0.4 oz/100 lb) and transported
The glycerol treatment “maintained 30% greater plasma concentration of glucose than controls and 14% greater than transported-only and betaine groups. The authors concluded that glycerol treatment showed promise in “attenuating the effects of long distance transportation by maintaining body water, decreasing the energy deficit, and preserving health and muscle quality. (J. Animal Sci. 85:2916)
EFFECTS OF CORN GLUTEN FEED & ROUGHAGE LEVEL ON FED CATTLE
Various co-products of corn processing, such as wet corn gluten feed (WCGF), are an important ingredient in many feedyard rations today. WCGF is a good source of highly digestible fiber and crude protein. Texas Tech researchers divided 200 Brangus-Angus crossbred steers averaging 691 lb into:
- controls on a standard steam-flaked corn ration with 9% roughage (alfalfa hay)
- standard ration, but with 40% WCGF and 9% roughage
- standard ration, but with 40% WCGF and 4.5% roughage
- standard ration, but with 40% WCGF and 0% roughage.
Cattle were fed once a day enough to ensure ad lib consumption. All rations had 14% CP (DM basis), which required 6.1%, 0%, 1.2%, and 2.3% cottonseed meal (in the order of the treatments listed above). The control ration also had 4.25% molasses for conditioning. Compared to the three WGCF groups combined, controls ate less but ADG did not differ, so they were more efficient. Among the WGCF rations, as roughage increased so did consumption and ADG, but not efficiency. More controls were at the bunk during the first hour after feeding. There were no significant differences in any carcass trait.
A second study divided 1983 “crossbred” steers (averaging 746 lb) from multiple Southern Great Plains sources into:
- the same standard control ration as in the first study
- standard ration, but with 20% WGCF and 9% roughage
- standard ration, but with 40% WGCF and 9% roughage
- standard ration, but with 40% WGCF and 4.5% roughage.
As in the first study, controls ate less and were more efficient, but ADG also was higher. Among the three WGCF groups, there were no significant differences between 20% and 40% or between the two roughage levels, except that 4.5% roughage was more efficient than 9%. Contrary to the first study, controls had lower dressing percent, lighter carcasses, and lower percent Choice. The 20% WGCF had higher dressing percent and higher percent Choice than 40% WGCF. There were no significant effects of roughage level on carcass traits.
The authors concluded that WCGF can be used effectively in feedyard rations by decreasing the need for supplemental protein and molasses without any adverse effects on feeding performance or carcass merit. (J. Animal Sci. 85:3079)
WHAT MAKES CATTLE COMFORTABLE
Australian researchers wondered what cattle might prefer to associate with after release from a squeeze chute. The study used 12-month-old Angus heifers. Individual heifers were evaluated only once. After being driven into the chute and confined for two minutes, with a handler standing in front of the heifer for the first 30 seconds, heifers had the following choices of pens:
- pen containing three familiar heifers or pen with hay on a metal rack and no heifers
- pen with heifers or bare pen with no heifers or hay
- pen with hay or bare pen.
The results: more heifers went with their peers than with the hay; even more went with their peers than into a bare pen; and there was no difference between hay or bare pens. In a second study the choices were:
- pen with a handler standing inside or pen with an orange-painted tire hanging in the middle
- pen with a handler standing outside or pen with the tire
- pen with a handler sitting inside or pen with the tire.
In all cases, fewer heifers chose the pen with a handler, especially a handler inside the pen.
The authors concluded that “just after handling with restraint, returning cattle to a group of peers and not approaching the cattle needlessly should moderate their stress.” So, cattle had rather be near cattle than humans, especially if a human has just driven them into a chute and confined them for two minutes. (J. Animal Sci. 85:1080)
HERITABILITY OF REPRODUCTION
University of Georgia and University of Uruguay researchers collaborated to study heritability of reproductive traits using 6763 first- through third-parity records of 3442 spring-calving Angus females. Data came from the Uruguayan Aberdeen-Angus Recording System. Traits evaluated were calving day (CD)and calving success (CS). Average age at first calving was 35.4 months. CS for first, second, and third parity were 86.3%, 65.9%, and 67.3%, respectively. The authors noted that open cows must be included in order to best use CD data. Three methods were used to adjust the data for open cows. Depending on the method, heritabilities for CD ranged from 0.20 to 0.31 and were highest for first parity and lowest for third parity. For CS, heritabilities ranged from 0.37 to 0.42. The authors concluded that, in purebred seedstock herds, “calving date is readily observed, reported when calves are registered, shows sizeable genetic variation, is a good indicator trait for fertility, and could be an option for genetic evaluation of reproduction.” (J. Animal Sci. 85:2854)
VACCINES FOR E. COLI
Occasional, periodic outbreaks of contamination from the harmful E. Coli 0157:H7 continue to plague our food supply, including beef. University of Nebraska researchers used 608 steers as follows:
- unvaccinated controls
- one dose at day 42
- two doses, at day 0 (arrival) and at day 42
- three doses, at days 0, 21, and 42.
In the above order of treatment, vaccine efficacy was 68%, 66%, and 73%. Also, unvaccinated cattle housed in the same pen as vaccinated were 59% less likely to shed E. coli 0157:H7.
In a second study, using 288 steers, treatments included three doses at 3-week intervals. Fecal samples were collected at arrival and at two, four, six, and eight weeks thereafter. Vaccinated cattle were 98.3% less likely to have E. coli 0157:H7. Vaccination may help reduce problems from E. coli contamination. (Jour. of Food Protection 70:2561 and 2568.)
DOES AGE & SOURCE VERIFICATION PAY
Yes, according to data compiled by the Montana Beef Network, a partnership between the Montana Stockgrowers Association and Montana State University. Sales were analyzed of almost 70,000 Montana calves in 590 lots at Superior Video Auctions in June and July of this year. Calves averaged 585 lb, $117.24/cwt, and 116 head sold per rancher, and about 2/3 of the calves were black . Overall, 31% were source and age verified. Only 15% had been weaned but about 80% of those went through VAC 45 (prescribed vaccinations/deworming and 45-day postweaning preconditioning). Almost 90% of the unweaned calves went through VAC 34 (prescribed vaccinations only). Bonuses ($/cwt) were:
- steer over heifer ($8.74)
- weaned over not weaned ($2.94)
- truckload lot size ($2.11)
- VAC 34/VAC 45 ($2.47)
- source and age verified ($2.14)
Regardless of marketing method, official verification of source and age must be done through an accredited USDA Process Verified Program. Producers can be accredited individually. But it’s usually easier to work with accredited cattlemen’s organizations, feedyard associations, marketing entities, etc. (Four-State Beef Newsletter of Montana, North Dakota, South Dakota, Wyoming: November, 2007)