Growth performance and carcass traits of pigs subjected to marginal dietary restrictions during the grower phase.

Abstract

Sixty-four individually housed pigs were used to investigate the effect of amino acid content of finisher diets on growth performance of pigs subjected to marginal dietary amino acid restrictions (80% of the 1988 NRC lysine recommendation) during the grower phase. In each of the two trials, low- and high-amino-acid grower diets (.421 and .765 g lysine/MJ DE, respectively) and four finisher diets (.421, .516, .612, and .707 g lysine/MJ DE) were randomly assigned within sex to 16 gilts and 16 castrated males weighing 23.0 +/- 2.0 kg in a 2 x 4 factorial arrangement of treatments. The average weight of pigs after a completion of diet change was 50.4 +/- 2.1 kg. All pigs were slaughtered at an average weight of 105.2 +/- 4.1 kg. Ultrasound backfat thickness was measured at the time of diet change and before slaughter. Pigs were allowed ad libitum access to feed and water. During the grower phase, pigs fed the high-amino-acid diet grew faster (P < .001) and more efficiently (P < .001) and had less ultrasound backfat (P < .001) than those fed the low-amino-acid diet. The grower diet had no effect on weight gain during the finisher phase. Consequently, pigs fed the high-amino-acid grower diet had better overall weight gain (P < .01) than those fed the low-amino-acid diet. The rate of lean accretion was, however, similar between the two groups of pigs. Furthermore, pigs fed the low-amino-acid grower diet seemed to have better carcass quality, as indicated by less ultrasound backfat (P < .01) and larger carcass longissimus muscle area (P < .05). Average and 10th rib carcass backfat decreased linearly (P < or = .05) and lean accretion rate improved linearly (P < .05) as the amino acid content of finisher diets increased, but there was no grower x finisher diet interaction in these and other response criteria. Although no evidence of compensatory weight gain was observed, it is possible that compensatory lean tissue growth may have occurred in pigs subjected to early amino acid restrictions at the expense of fatty tissue growth.

The effect of granulated barley as single major ingredient in the growing or finishing diet on productive performance, carcass, meat and fat quality of heavy pigs

“…Critser et al (1995) found that a reduction from 18.4% to 13.1% CP in the diet during the growing-finishing period (42 to 102 kg BW) decreased ADG and impaired FCR in gilts. In addition, Chiba et al (1999) observed that a reduction of lysine concentration in the growing diet (23 to 50 kg BW) decreased ADG and increased FCR in the combined growing-finishing period (23 to 105 kg BW), but reduced ultrasound backfat at slaughter, which was also observed in the present experiment.…”

“…However, when the cereal was provided during the growing period, fat thickness at the level of GM muscle decreased. In this respect, Chiba et al (1999) found that backfat thickness decreased or increased if the dietary lysine concentration was reduced in the growing or the finishing period, respectively.…”

Effect of a moderate feed restriction on subsequent growth and body composition in pigs raised under high environmental temperatures

“…Moreover, the higher ADFI of R pigs during the post-restrictive period should have increased their maintenance heat production, due to a weight increase of active metabolic organs (Koong et al, 1985), as well as the expenses of heat corresponding at a greater feed intake and more active digestion and metabolism . There are some previous reports indicating that temperature can modify overall growth in compensatory growth experiments (Donker et al, 1986;Chiba et al, 1999).…”

“…Moreover, the differences observed among experiments are probably related to differences in intake capacity and growth potential of the pigs used and to environmental conditions (Donker et al, 1986;Chiba et al, 1999;Daza et al, 2003).…”

Mechanism of Compensatory Growth with Changing Levels of Dietary Lysine from Deficient to Sufficient in Pigs

“…These studies indicate that sufficiency in dietary protein and amino acid contributes to triggering compensatory growth in pigs. However, compensatory growth was only observed in some studies (Chaosap et al 2011, Martínez-Ramírez et al 2009, Martinez-Ramirez et al 2008, O'Connell et al 2006; in other studies, compensatory growth was incomplete or absent (Chiba et al 1999, Pond & Mersmann 1990, Skiba et al 2001, Yang et al 2008a. Therefore, how compensatory growth can be induced and the underlying mechanisms remain to be elucidated.…”