Suchergebnisse

Two experiments were conducted to determine the effects of dietary net energy content (NE) on performance and carcass traits of finishing barrows fed low crude protein (CP) diets. Pigs (60.0 ± 2.41 kg, Exp. 1; 90.0 ± 2.96 kg, Exp. 2) were allotted in randomized design to four dietary treatments. Exp. 1 had nine pens treatment-1 and Exp. 2 had eight pens treatment-1, with two pigs in all pens. The treatments were as follows: 179 g kg-1 CP and 2589 kcal NE kg-1, 134 g kg-1 CP and 2631 kcal NE kg-1, 134 g kg-1 CP and 2589 kcal NE kg-1, and 134 g kg-1 and 2589 kcal NE kg-1 (pair-feeding to 179 g kg-1 CP and 2589 kcal NE kg-1) in Exp. 1 and 166 g kg-1 and 2604 kcal NE kg-1, 123 g kg-1 CP and 2645 kcal NE kg-1, 123 g kg-1 CP and 2604 kcal NE kg-1, and 12.34% CP and 2604 kcal NE kg-1 (pair feeding to 166 g kg-1 CP and 2604 kcal NE kg-1) in Exp. 2. In Exp. 1, there was no effect of CP or NE on any performance and carcass traits evaluated. In Exp. 2, the greatest result of average daily gain was obtained with 123 g kg-1 CP and 2645 kcal NE kg-1. There was no effect of CP or NE on any other performance and carcass traits evaluated. For 60 to 90 kg barrows, reducing the CP of the diet from 179 g kg-1 to 134 g kg-1, adjusting or not adjusting the NE content of the diets with 134 g kg-1 CP does not compromise performance or carcass traits. For 90 to 110 kg barrows, reducing the CP of the diet from 16.62 to 123 g kg-1, while maintaining the same NE content (2604 kcal kg-1) of the diet with 166 g kg-1 CP does not compromise performance or carcass traits.

The objective of the study was to evaluate the effects of glutamine and glutamate (Gln/Glu) on the growth performance and immune response of nursery pigs fed different digestible lysine content. Two hundred and sixteen piglets, weaned at 21 days old, were assigned to a randomized block design according to their initial body weight (BW), in a 2 × 2 factorial arrangement with two levels of lysine (control-lys and low-lys) and two levels of Gln/Glu (0 and 12 g kg-1), with nine replicates. At 26 d, piglets consuming the low-lys diet not supplemented with Gln/Glu presented a higher (P < 0.01) incidence of diarrhea than the other treatments. From 21 to 32 d of age, the piglets fed the control-lys diets performed better than those fed low-lys diets (P < 0.01). From 21 to 42 d of age, there was a correlation (P < 0.01) between lysine level and Gln/Glu supplementation for average daily feed intake (ADFI) and feed conversion (FC). Gln/Glu supplementation improved (P < 0.05) the ADFI of pigs fed the low-lys diets, resulting in a higher (P < 0.01) average daily weight gain (ADG) and BW; however, worse (P < 0.05) FC. Piglets consuming control-lys diets had higher (P < 0.05) serum urea nitrogen concentration (SUN) and IgG than low-lys piglets. In addition, Gln/Glu supplementation correlated with higher (P < 0.01) SUN. Dietary supplementation of glutamine and glutamate improved the growth performance of weaned piglets from 21 to 42 days of age, regardless of the diets' lysine levels. In addition, reducing lysine levels 10% below the requirement negatively affects the growth performance and the immune response of nursery piglets.