RESUMO
This study investigated the effect of supplementation of Malva sylvestris leaf powder (MSLP) on the production performance of broiler chicken. Ven Cobb broiler chicks (240 day-old male chicks) were distributed randomly into four treatments, each replicated four times, with 15 birds per replicate. The diets formulated were T1 (control) given basal diet only, T2 (basal diet +1.0% MSLP), T3 (basal diet +1.5% MSLP), and T4 (basal diet +2.0% MSLP). The highest improvement of 3.83% in the average daily gain (ADG) was recorded in the T3 group fed 1.5% Malva powder in the diet compared to the control (P = 0.009). The average daily feed intake (ADFI) tended to decrease with an increase in the dose of MSLP in the diet, with the lowest feed intake in the T4 group fed 2% MSLP. During the overall period (7-42 days), the feed/gain (F/G) ratio reduced significantly (P = 0.048) in the T3 and T4 groups compared to the control. The dressed and breast meat yield was found to be significantly (P < 0.05) higher in the T3 group, with no significant change (P > 0.05) in the thigh yield. The changes in the pH and water-holding capacity (WHC) of breast meat were found to be non-significant (p > 0.05) between the control and various other treatments. Thiobarbituric acid-reactive substances (TBARS) were significantly (P < 0.05) decreased in the T3 and T4 groups. There was no negative effect of including MSLP in the diet on the color coordinates of breast meat among different treatments. Compared to the control, the serum immunoglobulin values increased significantly (P < 0.05) in the T3 and T4 groups. Superoxide dismutase (SOD) showed no difference between various treatments; however, malondialdehyde (MDA) decreased significantly (P < 0.05) according to dietary treatments. Serum cortisol increased significantly (P < 0.05) in the T4 group compared to other treatments. The inclusion of Malva powder in the diet at the 2% level significantly (P < 0.05) decreased the coliform count compared to the control birds. Supplementation with Malva powder resulted in a significant (P < 0.05) increase in the villus height-to-crypt depth (VH:CD) ratio of broiler birds in the T3 and T4 groups. In conclusion, MSLP supplementation at 1.5% and 2% resulted in improved production performance of broiler chicken.
RESUMO
This study evaluated the effect of free and nanoencapsulated rosemary essential oil (REO) as an antibiotic alternative in broiler diets on growth performance, nutrient digestibility, carcass traits, meat quality and gene expression. Four hundred twenty day-old commercial broiler chicks (VENCOBB) were randomly allocated to seven dietary treatments, each having four replicates of fifteen chicks. The dietary treatments comprised control (CON) fed a basal diet only, AB (basal diet + 10 mg enramycin/kg), CS (basal diet + 150 mg chitosan nanoparticles/kg), REOF100 and REOF200 (basal diet + 100 mg and 200 mg free REO/kg, respectively), and REON100 and REON200 (basal diet + 100 mg and 200 mg nanoencapsulated REO/kg, respectively). Overall (7-42 d), REON200 showed the highest (p < 0.001) body weight gain (1899 g/bird) and CON had the lowest gain (1742 g/bird), while the CS, REOF100 and REOF200 groups had a similar gain, but lower than that of the AB and REON100 groups. Feed intake was not affected by dietary treatments. Overall, the feed efficiency increased (p = 0.001) by 8.47% in the REON200 group and 6.21% in the AB and REON100 groups compared with the CON. Supplementation of REO improved (p < 0.05) dry matter and crude protein digestibility, with the highest values in REON100 and REON200. Ether extract, crude fiber, calcium and phosphorus digestibility values showed no difference among the groups. The dressing, breast, thigh % increased (p < 0.05) and abdominal fat % decreased (p < 0.001) more in the REON200 group than with other treatments and CON. In breast meat quality, water holding capacity and extract reserve volume increased (p < 0.05) while drip loss and cholesterol content decreased (p < 0.05) in REON100 and REON200. No change was observed in the breast meat color among dietary treatments and CON. The REON100 and REON200 groups had reduced (p < 0.05) meat lipid peroxidation as depicted by the decreased levels of TBARS, free fatty acids and peroxide value compared to other treatments and CON. The expression of the Mucin 2, PepT1 and IL-10 genes was upregulated (p < 0.001) and TNF-α downregulated (p < 0.001) by dietary addition of REO particularly in the nanoencapsulated form compared with the CON. In conclusion, nanoencapsulated REO, especially at 200 mg/kg diet, showed promising results as an antibiotic alternative in improving the performance, nutrient digestibility, carcass traits, meat quality and upregulation of growth and anti-inflammatory genes.