Effects of dietary probiotic (Pediococcus acidilactici) supplementation on productive performance, egg quality, and body composition in laying hens fed diets varying in energy density.

This study was conducted to determine the effect of probiotic Pediococcus acidilactici (PA) strain MA18/5M supplementation of diets with different dietary energy levels on productive performance, egg quality, and body composition in Hy-Line Brown hens during a 16-week period from 32 to 47 wk of age. The experimental treatments with a 2 × 2 factorial design received a 2 wheat-corn-soybean diet: a moderately low energy density diet with 2,650 kcal ME/kg (M-LED) and a low energy density diet based on the M-LED diet with 2,550 kcal ME/kg (LED), each diet without and with probiotic supplementation (M-LED, LED, M-LEDp, and LEDp, respectively). Reduced dietary energy levels had a particularly negative effect on egg weight (61.7 vs. 63.3 g; -2.6%, P < 0.001), egg mass output (1.67 vs. 1.71 kg; -2.4%, P = 0.015), and FCR (2.01 vs. 1.97 kg feed/kg egg; +2%, P = 0.028). In hens administered the LED diet, deteriorated productive performance was accompanied by greater body weight loss (P < 0.001) and reduced abdominal fat content (P < 0.033) as compared with the M-LED group. Dietary probiotic inclusion increased egg weight (P = 0.015), including relative eggshell weight (P = 0.008) and eggshell thickness (P = 0.002) and significantly improved FCR (P = 0.010). No interactions between the PA-based probiotic and dietary energy levels were found in any of the tested parameters. Adding the probiotic on top of the M-LED diet improved layers performance but resulted in nonbioequivalence for the egg weight, egg mass output, and FCR compared with this group without probiotic. Probiotic supplementation of the LEDp diet improved all performance parameters except for egg weight. As a result, the laying rate, egg mass output, daily feed intake, and FCR in the LEDp treatment were bioequivalent to those noted in the M-LED group without the probiotic. The results of a bioequivalence test suggest that a low energy diet fed to laying hens promoted a probiotic response to improve energy utilization by birds.

The effect of different dietary ratios of arginine, methionine, and lysine on the performance, carcass traits, and immune status of turkeys.

The research hypothesis postulated that the optimal dietary inclusion levels and ratios of lysine (Lys), arginine (Arg), and methionine (Met) can increase the growth potential of hybrid turkeys and limit metabolic disorders that weaken immune function. The experiment was carried out in a full rearing cycle, from 1 to 16 wk of age, in a two-factorial randomized design with 3 levels of Arg and 2 levels of Met (90, 100 and 110% of Arg, and 30 or 45% of Met, relative to the content of dietary Lys), with 6 groups of 8 replicates per group and 18 turkeys per replicate. In the first and second month of rearing, a significant dietary Arg-by-Met interaction was noted for daily feed intake and body weight gain, and a more beneficial effect was exerted by higher Met content and medium Arg content. Throughout the experiment, the higher dietary Met level increased the final body weight (BW) of turkeys (P = 0.001). Different dietary Arg levels had no influence on the growth performance of turkeys, but the lowest level decreased dressing yield (P = 0.001), and the highest level increased the percentage of breast muscles in the final BW of turkeys (P = 0.003). The lowest Arg level (90% of Lys content) undesirably increased the concentration of the proinflammatory cytokine IL-6 (P = 0.028) and decreased globulin concentration (P = 0.001) in the blood plasma of turkeys. The higher dietary Met level (45% of Lys content) increased plasma albumin concentration (P = 0.016). It can be concluded that higher dietary levels of Met (45 vs. 30% of Lys content) and Arg (100 and 110 vs. 90% of Lys content) have a more beneficial effect on the growth performance and immune status of turkeys.

Growth performance, gastrointestinal function and meat quality in growing-finishing turkeys fed diets with different levels of yellow lupine (L. luteus) seeds.

The aim of this study was to evaluate the effects of a different dietary content of sweet yellow lupine seed meal (YLM) on gastrointestinal tract development and function, the growth performance (13-18 weeks of age) and meat quality of growing-finishing turkeys. Control grower and finisher diets contained soybean meal (SBM), and in experimental diets, SBM was replaced with YLM at 6%, 12% and 18% (Groups L6, L12 and L18, respectively). The diets were formulated to be iso-nitrogenous and iso-energetic. In the first phase of feeding, YLM tended to decrease feed intake (p = 0.087) and body weight gain (BWG, p = 0.078) linearly due to significant deterioration in feed conversion ratio (FCR, p = 0.030). An opposite trend was noted in the second phase of feeding: BWG increased (p = 0.069) and FCR improved significantly (p = 0.004). Over the entire experiment, inclusion of YLM did not affect feed intake, BWG, FCR or excreta dry matter (DM) content. The highest YLM dietary level had no adverse effects on fermentation processes in the caeca. Positive changes, which were observed in turkeys fed YLM-supplemented diets, included an increased gizzard weight, a decreased pH of gizzard contents and a decreased viscosity of small intestinal digesta. The inclusion of YLM at 18% had no effect on carcass quality, the pH and colour intensity of breast meat. The highest inclusion rate of YLM (18%) in turkey diets significantly (p < 0.05) intensified the fatty flavour of meat and increased its hardness, springiness and chewiness, whereas it had no effect on the appearance, aroma and overall acceptability of breast meat. It can be concluded that YLM at the highest dietary rate used in the present experiment (18% of the diet) had no adverse effects on the growth performance or the analysed physiological parameters of turkeys.