Effects of Dietary Protein Level and Environmental Temperature on Performance and Carcass Quality of Growing-Finishing Swine

Growth and backfat depth of pigs kept at a high temperature

“…However, the present results do not agree with those of Seymour et al (1964) nor with those of Sugahara et al (1970), obtained with pigs, who found that high temperature either had no effect on backfat depth or reduced it respectively. Where food intake was not affected or decreased by less than about 10% at the higher temperatures, backfat depth increased (Tonks and Smith, 1968), and present results) or was not changed (Seymour et al, 1964); but where food intake decreased by about 30%, backfat depth decreased (Sugahara et al, 1970). Where food intake was not affected or decreased by less than about 10% at the higher temperatures, backfat depth increased (Tonks and Smith, 1968), and present results) or was not changed (Seymour et al, 1964); but where food intake decreased by about 30%, backfat depth decreased (Sugahara et al, 1970).…”

Substitution rates and economic optima in corn-soybean rations for growing-finishing swine

“…Although the higher levels of pro tein increased average daily gain for the entire period, the effect was inconsistent among the stages. Seymour et al (1964) found that corn-soybean meal rations consisting of 17 percent protein from seven weeks of age to 125 pounds of body weight and l4 percent from 125 to 200 pounds were superior to rations containing 4 percentage units less protein. Protein levels of 17 percent to 100 pounds and 15 percent thereafter resulted in significantly more rapid and efficient gains than 4 percentage units less protein, as noted by Wallace et (1963).…”

“…Many recent studies (Bowland et , 196IJ Stevenson _£t , 196O;Beacom, 1959b;Seymour et al, 1964;Wallace _et al, 1963) have shown that increasing the protein level above N. R. C, (National Academy of Sciences, 1959) recommendations during the three stages of the growingfinishing period will increase carcass characteristics such as percent lean cuts and rib eye area. Wallace e;Ë Èl- (19^3) noted significantly higher dressing percent on 13 percent protein for pigs to 100 pounds of body weight and 11 percent thereafter than for rations containing 4 percentage units more protein at each stage.…”

Substitution rates and economic optima in corn-soybean rations for growing-finishing swine

“…Protein levels of l4, 16 and 18 percent for pigs from 40 to 130 pounds and 10, 12 and l4 percent from 130 to 200 pounds produced significantly leaner carcasses than protein levels of 12 and 9 percent for those weight ranges (Wahlstrom, 1954). Wallace et al (1954) Recent trials Many recent studies (Bowland et , 196IJ Stevenson _£t , 196O;Beacom, 1959b;Seymour et al, 1964;Wallace _et al, 1963) have shown that increasing the protein level above N. R. C, (National Academy of Sciences, 1959) recommendations during the three stages of the growingfinishing period will increase carcass characteristics such as percent lean cuts and rib eye area. Wallace e; noted significantly higher dressing percent on 13 percent protein for pigs to 100 pounds of body weight and 11 percent thereafter than for rations containing 4 percentage units more protein at each stage.…”