Hematological and Biochemical Parameters in Aged Cobb 500 Broiler Breeder Roosters Fed Dried Pomegranate Peels

Extended Abstract Background: Benefiting from agricultural and garden residues is an efficient management tool to improve productivity in supplying protein needed by humans from animal sources (livestock and poultry). One of these residues is the waste resulting from harvesting and consumption of pomegranate fruits, one of the most important garden products in Iran. The peel and pomace of this fruit make up to 45% of its weight. Pomegranate is a fruit with high antioxidant properties that plays an important role in dealing with oxidative stress and can probably affect the hematological and biochemical blood parameters of living organisms. Therefore, this research aimed to investigate the blood parameters of old broilers fed with pomegranate peel to identify the possible adverse effects of this residue on hematological and biochemical parameters. Methods: This research was conducted in the Faculty of Agriculture, Shiraz University, located 15 km northeast of Shiraz. Thirty-six 64-week-old roosters (Cob 500 strain) were assigned to three treatments in a completely random design, each with nine replicates of four birds. The experimental treatments included a T0 base diet without pomegranate peel and T10 and T20 diets with 10% and 20% pomegranate peel, respectively. To adapt to the experimental treatments, the roosters were fed experimental diets for 6 weeks, and blood samples were taken weekly from the brachial vein to examine blood hematological and biochemical parameters, including total number of white and red blood cells (WBC & RBC, resp.), WBC differential count (lymphocytes, monocytes, heterophils, and eosinophils), total protein concentration, albumin, total cholesterol, HDL (high-density lipoprotein), LDL (low-density lipoprotein), VLDL (very low-density lipoprotein), triglyceride, alkaline phosphatase, alanine aminotransferase (ALT), aspartate aminotransferase(AST), glucose, urea, and phosphorus. Data were analyzed with SAS software. This research was done in a completely randomized design, and the data were analyzed with a mixed procedure. The least squares means of the treatments, after correction for multiple comparisons based on Tukey's test, were compared at a significance level of 5%. Results: The main effect of experimental treatments was not significant on all the hematological parameters, and the main effect of time was significant only for monocytes (P < 0.05). The interaction of diet and time was significant only for the total number of RBCs (P < 0.05) and monocytes (P < 0.05). The main effect of the diet was decreasing on the concentrations of total cholesterol, LDL, and triglycerides while it was increasing on the concentration of HDL, glucose, alkaline phosphatase (ALP), and phosphorus. The effect of time was significant on the concentrations of total protein, total cholesterol, ALT, AST, and phosphorus. The interaction of diet and time significantly affected total cholesterol, ALP, AST, and phosphorus (P < 0.05). The analysis of variance showed the effect of diet, time, and the interaction of diet and time on the hematological parameters of Cobb 500 broilers fed with pomegranate peel powder. The effect of diet was not significant on all the hematological parameters. The effect of time was significant only on the percentage of monocytes (P < 0.05). The interaction of diet and time was significant on the total number of RBCs and the percentage of blood monocytes (P < 0.05). Weekly changes in the percentage of monocytes showed that the trend of changes during the experiment was increasing in the groups that received a high level of pomegranate peel powder (T20). From the second to the fifth weeks, the group in the T10 treatment showed a sharp decrease in the percentage of blood monocytes. Pomegranate peel powder feeding was associated with changes in blood concentrations of some biochemical parameters. Blood cholesterol concentration decreased in birds of the T20 and T10 groups. LDL and triglyceride concentrations decreased in birds fed with pomegranate peel powder at both feeding levels. In contrast, the concentrations of HDL, ALP, glucose, and phosphorus increased in these birds. The interaction effect of time and diet was also significant on the concentrations of cholesterol, ALP, phosphorus, and AST. Among the hematological parameters in birds fed with pomegranate peel powder, the percentage of monocytes was affected by time and the interaction of diet and time. Moreover, the total number of RBCs was affected by the interaction of diet and time. Conclusion: Despite the significant differences in some of the mentioned parameters (monocytes, total number of RBCs, concentrations of total cholesterol, LDL, triglyceride, HDL, glucose, ALP, total protein, AIT, AST, and phosphorus) during the six-week period of pomegranate peel powder feeding in old broiler Cobb-500 chickens, the fluctuation range was in the normal physiological range. Therefore, pomegranate peel feeding at the tested levels (0, 10, and 20) was not associated with obvious damage to the general health and biochemical profile of birds. According to the findings of this research, it can be concluded that, although the nutrition of pomegranate peel powder could influence a number of blood parameters during the six-week feeding period, the fluctuation was within the normal physiological range despite the difference in the mentioned parameters. Therefore, pomegranate peel feeding at the levels used here was not associated with obvious damage to the general health and clinical profile of birds.