Beef Cattle Browsing
Editor: Dr. Stephen Hammack, Professor & Extension Beef Cattle Specialist Emeritus
March 2004
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.
SCOURS IN CALVES
Montana State University researchers studied records from 3637 calves over 14 years. Incidence of scours over those years averaged 35 % (ranging from 13% to 64%), was significantly higher in calves nursing two-year-old dams, and decreased with increasing age of dam. Also, linebred Hereford calves scoured more than outbred Herefords or Hereford crossed with Angus, Simmental, or Tarentaise. Weaning weight was 20 pounds lighter for calves that scoured. (Prof. Anim. Sci. 19:399)
GENE TEST FOR MARBLING
The GeneSTAR® test identifies individuals that have zero, one, or two copies of a gene thought to be related to increased levels of marbling, the primary factory in USDA Quality Grade. In one study, progeny of 2-star sires averaged 527 units of marbling compared to 516 units for 0-star sires (where 400 equals Slight marbling, 500 equals Small, etc.). However, progeny of 2-star sires graded 65% Choice, compared to 47% for 0-star. How could such a small difference in marbling result in such a large difference in grade? Notice that the average marbling levels are very near 500, the line between Choice and Select. When you are close to such a discrete division, a little difference can mean a lot. (National Beef Cattle Evaluation Consortium Seminar, Feb. 9, 2004)
NEW MODIFIED – LIVE BRD LABEL FOR PREGNANT COWS
Modified-live virus vaccines for BRD (Bovine Respiratory Disease) have never been cleared for pregnant cows or calves nursing pregnant cows. Why? In the early stages of development of such vaccines, there was some indication that a low level of abortions might possibly occur in such applications. In some areas, in herds where strict calving seasons are employed and replacement females are vaccinated early in life and regularly thereafter with modified-live products, calves have often been vaccinated with such products without ill effects. Now there is a product with a label clearance for such use. According to Pfizer’s label “ The Bovi-Shield® GOLDTM line and PregGuard® GOLDTM FP 10 may be administered to pregnant cattle provided they were vaccinated, according to label directions, with the Bovi-Shield FP line or the Bovi-Shield GOLD FP line prior to breeding initially and within 12 months thereafter. The Bovi-Shield GOLD line may also be administered to calves nursing pregnant cows provided their dams were vaccinated prior to breeding as described above”. (Pfizer Animal Health)
MAD COW THREAT?
According to the U. S. Center for Disease Control, the odds of mad cow infection are about the same as winning the lottery and being struck by lightning, in the same day! Nevertheless, we have all seen the effects that one case of BSE can cause. There is something powerful about the vision of getting holes in your brain that stirs public interest, even if the likelihood is extremely small.