Arkansas researchers conducted three experiments involving vaccination for clostridial diseases. All vaccines were injected subcutaneously in the neck. In one study, mature cows were vaccinated once with 2ml of Alpha-7TM (A-7) about 90 days before calving. At birth, half of their calves also received 2ml of A-7. Blood samples taken every 28 days for four months indicated no difference in antibody response between vaccinated and non-vaccinated calves. In a second study, weaned heifers received either 2ml of A-7 or 5ml of Ultrabac 7TM (UB7) boosted 28 days later. Blood samples were taken every 28 days for six months. A-7 antibody response was higher at 28 days, UB7 was higher at 56 days, by 112 days there was no difference, and by 140 days there were no detectable levels. In the third study, weaned heifers received A-7. After 28 days, 65% had visible injection-site lesions. Heifers with lesions had higher antibody responses at 28, 56, and 84 days, but not by 112 days. So, if there is a knot on the neck you're pretty well assured that (1) the cattle were vaccinated, (2 ) it was done in the right location, and (3) the vaccine probably took. But you still might be docked at the sale barn. Some things are hard to change.
EFFECTS OF LIQUID FEED ON COW/CALF PERFORMANCE
New Mexico workers fed cows 35% CP molasses-urea liquids with or without fat for 114 days. Consumption was controlled at 2 lb/cow. After 72 days, supplemented cows had 0.7 higher BCS than unsupplemented cows. At the end of feeding, calves on supplemented cows were 26 lb heavier. Calves from cows on the fat supplement weighed 6 lb more than the non-fat supplement.
ARE CATTLE REALLY BEING DOWNSIZED?
It's generally agreed that a lot of cattle got too big in the race for size, and that we have been "downsizing" in recent years. True? Perhaps the best guide is genetic trend of yearling weight in registered cattle. Since 1972, Angus have increased about 75 lb genetically, going up steadily each year and still going. (Average actual yearling weights of Angus bulls have increased over 250 lb.) What about larger breeds? Simmental have increased genetically about 45 lb since 1973 (and are still going up), not as much as Angus but Simmental were pretty big already. All breeds show the same trend. What about frame? Frame score of Angus plateaued in 1990, and has averaged mid-5 since. So, cattle are heavier and height isn't changing. The purebred industry is selecting for larger bodies on the same frame. That's enlarging and reshaping, not downsizing.
REPLACEMENT HEIFERS - SAVE, BUY OPEN, OR BUY BRED?
Virginia researchers used computer simulations to compare saving heifers to grow out and breed, buying open heifers to grow out and breed, or buying bred heifers to replace open cows 60 days after the end of breeding season. Economics favored saving or buying open heifers over buying bred heifers. (Also, net profit was higher from grazing weaned calves for 80 days than from selling at weaning.) In some studies, economics favors buying bred replacements. Remember, you know the genetics and background of raised heifers. That may or may not be true when buying heifers.
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