Date of Award
Master of Science
Monty J. Montgomery
D. O. Richardson, R. N. Heitmann
Thirty-six Holstein replacement calves were randomly assigned to one of two treatments. Treatment I was composed of a two-stage complete ration utilizing cottonseed hulls as the fiber source. Stage one (ration la) consisted of 20 percent cottonseed hulls, 60 percent corn, and 20 percent soybean meal. Ration Ia was fed ad libitum to calves three weeks of age up to approximately 300 pounds body weight. Stage two (ration lb) consisted of 43 percent cottonseed hulls, 43 percent com, and 14 percent soybean meal. Ration lb was fed ad libitum to calves which achieved a body weight of approximately 300 pounds and continued to 30 weeks of age. Treatment II consisted of long alfalfa hay fed ad libitum plus an 18 percent grain concentrate fed separately ad libitum. Significant differences (P < 0.05) were found between treatments in daily dry matter intake. Daily dry matter intake (pounds) for calves consuming ration la and II from three to 21 weeks of age were 5.5 and 4.5, respectively. Calves from 18 to 30 weeks of age fed ration lb and II consumed 13,8 and 11.1 pounds of feed, respectively. No significant difference was found between daily dry matter intake per hundred pounds body weight (cwt) of calves fed Treatments I and II. Significant differences in body weight (P > 0.05) (pounds) and heart girth (P < 0.05) (inches) measurement were detected between calves fed Treatments I and II. Body weights for calves three to 21 weeks of age fed ration la and II were 207 and 204 pounds, respectively. Calves consuming lb and II from 18 to 30 weeks of age had body weights of 416 and 379 pounds, respectively. Heart girth (inches) measurements for calves three to 21 weeks of age fed ration la and II were 42.7 and 40.3, while calves fed ration lb and II from 18 to 30 weeks of age had measure-ments of 51.7 and 49.3, respectively. No significant differences were detected in body length and wither height due to treatment. No significant differences were found between rumen pH or blood serum levels of calcium, phosphorus, and magnesium of calves fed Treat-ments I and II. Blood serum levels of phosphorus were slightly higher than "normal" for all treatments. Calves fed rations la, lb, and II had blood serum phosphorus levels of 9.0, 8.9, and 8.9 mg/100 ml, respec-tively. Significant differences (P < 0.05) between volatile fatty acids (VFA), acetate, and propionate were detected in calves fed ration la and II from three to 21 weeks of age. Molar percent values of acetate and propionate of calves fed ration la and II were 52.5, 31.0 and 63.1, 21.5, respectively. No significant differences were detected in VFA's of calves fed ration lb and II from 18 to 30 weeks of age. These data suggest that Holstein heifer calves can be raised successfully using a two-stage complete feeding program utilizing cottonseed hulls as the fiber source.
Migioia, Steven Nicholas, "Comparison of a conventional feeding program with a two-stage complete ration program utilizing cottonseed hulls as the fiber source for replacement heifers. " Master's Thesis, University of Tennessee, 1982.