Abstract
We conducted two trials with growing-finishing pigs (Pig Improvement Company line 405 x Camborough 15) to evaluate the effects of space allocation on performance and CP requirements. In Trial 1, a 2 x 3 factorial (two levels of space, three CP regimens) was used with 252 pigs. Pigs were allocated to either .23, .28, .37, or .50 m2 per pig (crowded) or .37, .47, .60, or .74 m2 per pig (uncrowded) during the 18 to 36, 36 to 55, 55 to 91, and 91 to 127 kg weight periods, respectively. Diets contained 16.1, 18.6, or 21.1% (18 to 36 kg), 15.3, 17.8, or 20.3% (36 to 55 kg), 14.7, 17.2, or 19.7% (55 to 91 kg), and 12.8, 15.3, or 17.8% (91 to 127 kg) CP. The 16.1, 15.3, 14.7, and 12.8 % CP (control) diets contained 1.09, .86, .82, and .65% lysine, respectively. Crude protein levels (Trials 1 and 2) were achieved by substituting soybean meal for corn. In Trial 1, a CP x space interaction ( P < .03) for gain:feed suggested that feed efficiency of grower pigs was improved to a greater extent in uncrowded pigs than in crowded pigs. Grower pigs (18 to 55 kg) with less space had depressed (P < .05) feed intake and gain and a lower (P < .10) feed efficiency than uncrowded pigs. Added CP improved (P < .05) rate and efficiency of gain in grower...Continue Reading