1- University of Jiroft
Abstract: (10 Views)
Introduction and objective: Many factors including disease and stress, can suppress the immune function of broilers and threaten their health. Vitamins A and E are fat-soluble vitamins that play an important role in production, growth, protection of tissues and cell membranes, cell proliferation and differentiation, and embryonic development. They are also effective in modulating the immune response, preserving the blood serum and tissues and reducing the inflammatory response. The antioxidant role of these vitamin supplements has been previously proven by researchers. In addition to improving growth and immunity, these vitamins can increase the oxidation stability of poultry meat by preventing oxidative damage. Therefore, this study investigated the effects of adding vitamin E and A supplements to the broiler diet on growth performance, immune response, and meat quality and stability of broilers.
Material and Methods: This experiment was conducted as a completely randomized design on 160 one-day-old Ross 308 male broilers with four treatments, four replicates, and 10 chicks per replication. Experimental treatments included, T1: Corn-soybean diet (control treatment without supplement), T2: basal diet + 250 mg of vitamin E, T3: basal diet + 1500 IU of vitamin A, T4: basal diet + 250 mg of vitamin E, and 1500 IU of vitamin A. Diets were formulated isocaloric and isonitrogenous, then vitamin A and E supplements were added to experimental diets. The performance traits such as feed intake and body weight gain, were recorded for three periods including starter (1-10 days), grower (11-24 days), and finisher (25-42 days), then feed conversion ratio, were determined. The Newcastle disease vaccination was done at 7 and 21 days of age, then blood samples were gathered at 28 days of age to measure the antibody production. The hemagglutination inhibition method was used to determine the antibody titer against the Newcastle disease agent. Also, blood samples were collected in heparin tubes to determine the number of heterophils and lymphocytes, and after homogenizing of the blood sample, its smear was prepared. Blood cells were fixed by methanol and stained with Giemsa solution. To measure the number of heterophils and lymphocytes, 100 cells were counted. At the end of the experiment, two birds per replicate with body weight close to the average of each cage were slaughtered. After slaughter, the breast and thigh were separated from the carcass and a part of it was transferred to the refrigerator to measure quality parameters and a part to the freezer to measure malondialdehyde. Meat quality characteristics, including water holding capacity, cooking loss, dripping loss and meat pH, were measured one day after slaughter. The content of malondialdehyde (Thiobarbituric acid test) of meat was measured at intervals of 30 and 45 days after slaughter.
Results: The results showed that the effect of vitamin A and E addition on feed intake, body weight gain and feed conversion ratio was significant during the grower, finisher, and whole period (P<0.05). The addition of vitamin A and E, increased feed intake and body weight gain and decreaesd feed conversion (P<0.05). The effect of vitamins A and E addition on antibody production, lymphocytes and heterophils percentage, and the ratio of heterophil to lymphocyte were significant (P<0.05). The supplementation of vitamins A and E, significantly increased the antibody production and percentage of lymphocytes while decreased the heterophil percent and heterophil to lymphocyte ratio (P<0.05), and the highest antibody production was seen in broiler feds by both vitamins (P<0.05). The addition of vitamin supplements, decreased meat cooking loss and dripping loss, while increased the water holding capacity (P<0.05). The effect of treatments on meat pH was not significant (P>0.05). The addition of vitamin A and E, decreased the malondialdehyde content in the thigh and breast meat at 45 days after slaughter (P<0.05) and the lowest malondialdehyde content was seen in broilers fed by both vitamins A and E (P<0.05).
Conclusion: It is concluded that adding 1,500 IU of vitamin A and 250 mg of vitamin E to the diet can improve growth performance, immune response, meat quality and stability in broilers.
Material and Methods: This experiment was conducted as a completely randomized design on 160 one-day-old Ross 308 male broilers with four treatments, four replicates, and 10 chicks per replication. Experimental treatments included, T1: Corn-soybean diet (control treatment without supplement), T2: basal diet + 250 mg of vitamin E, T3: basal diet + 1500 IU of vitamin A, T4: basal diet + 250 mg of vitamin E, and 1500 IU of vitamin A. Diets were formulated isocaloric and isonitrogenous, then vitamin A and E supplements were added to experimental diets. The performance traits such as feed intake and body weight gain, were recorded for three periods including starter (1-10 days), grower (11-24 days), and finisher (25-42 days), then feed conversion ratio, were determined. The Newcastle disease vaccination was done at 7 and 21 days of age, then blood samples were gathered at 28 days of age to measure the antibody production. The hemagglutination inhibition method was used to determine the antibody titer against the Newcastle disease agent. Also, blood samples were collected in heparin tubes to determine the number of heterophils and lymphocytes, and after homogenizing of the blood sample, its smear was prepared. Blood cells were fixed by methanol and stained with Giemsa solution. To measure the number of heterophils and lymphocytes, 100 cells were counted. At the end of the experiment, two birds per replicate with body weight close to the average of each cage were slaughtered. After slaughter, the breast and thigh were separated from the carcass and a part of it was transferred to the refrigerator to measure quality parameters and a part to the freezer to measure malondialdehyde. Meat quality characteristics, including water holding capacity, cooking loss, dripping loss and meat pH, were measured one day after slaughter. The content of malondialdehyde (Thiobarbituric acid test) of meat was measured at intervals of 30 and 45 days after slaughter.
Results: The results showed that the effect of vitamin A and E addition on feed intake, body weight gain and feed conversion ratio was significant during the grower, finisher, and whole period (P<0.05). The addition of vitamin A and E, increased feed intake and body weight gain and decreaesd feed conversion (P<0.05). The effect of vitamins A and E addition on antibody production, lymphocytes and heterophils percentage, and the ratio of heterophil to lymphocyte were significant (P<0.05). The supplementation of vitamins A and E, significantly increased the antibody production and percentage of lymphocytes while decreased the heterophil percent and heterophil to lymphocyte ratio (P<0.05), and the highest antibody production was seen in broiler feds by both vitamins (P<0.05). The addition of vitamin supplements, decreased meat cooking loss and dripping loss, while increased the water holding capacity (P<0.05). The effect of treatments on meat pH was not significant (P>0.05). The addition of vitamin A and E, decreased the malondialdehyde content in the thigh and breast meat at 45 days after slaughter (P<0.05) and the lowest malondialdehyde content was seen in broilers fed by both vitamins A and E (P<0.05).
Conclusion: It is concluded that adding 1,500 IU of vitamin A and 250 mg of vitamin E to the diet can improve growth performance, immune response, meat quality and stability in broilers.
Send email to the article author
| Rights and permissions | |
 |
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |
