Effect of Supplementation of Prebiotic Oligosaccharides to Diets Containing Zinc Propionate on Some Serum Enzymes, Metabolites and Electrolytes in Broilers

Background: Zinc is needed as essential for many physiological functions in humans and animals. Chitosan is a natural substance produced in the body from glucose and some biological effects such as antimicrobial and immune modification mechanisms. β-glucans are polysaccharides of D-glucose monomers and have important roles in antitumor and antimicrobial activity in animals. Inulin is used for its effects on immune function, bioavailability of minerals, lipid metabolism and gastrointestinal tract health. The aim of the study was to investigate the effects of chitosan oligosaccharide (COS), β-glucan, and inulin on some serum enzymes, metabolites and electrolytes in broilers. Materials, Methods & Results: A total of 96 male and 1-day-old Ross broiler chicks were used in the study. The ambient temperature was maintained at 33oC for the first 3 days, which was gradually reduced by 3oC a week until reaching 24oC. Chicks had free access to food and tab water. Basal diets containing the soybean meal and corn were prepared for starter (day 1 to 21) and grower (day 22 to 42) periods. Chicks were equally assigned to eight dietary treatment groups: Control (basal diet); Zn (zinc propionate, 1%); Chitosan (Chitosan, 0.025%); β-glucan (β-glucan, 0.05%); Inulin (inulin, 1%); Zn+Chitosan (zinc propionate, 1% + Chitosan, 0.025%); Zn+ β-glucan (zinc propionate, 1% + β-glucan, 0.05%) and Zn+Inulin (zinc propionate, 1% + inulin, 1%). Blood samples were collected from V. brachialis before feeding in the morning on days 21 and 42. Serum K levels were found lower in Zn+COS group than in COS and control groups on day 21 (P < 0.05). They were insignificantly different among all groups on day 42 in the study. Serum sodium levels were significantly higher in inulin group on day 21 and in control group on day 42 than other groups. Serum phospholipid levels were insignificantly different among control, COS and Zn+COS groups on days 21 and 42 in the present study. Serum creatine kinase (CK) activities were higher in β-glucan group and in Zn+Inulin group than other groups on day 42 (P < 0.05). Serum creatinine levels were significantly higher in Zn+Inulin group than control group, Zn group and Chitosan group on day 42. Serum gamma-glutamyl transferase (γ-GT) activities were the lowest in Chitosan group on day 42. Discussion: According to literature, antibiotics could be hazardous especially to human health when residues occurs and bacteria gains resistance against antibiotics. Chitosan and glucans have antibacterial functions. Therefore, they can be used as an alternative against antibiotics. Because of chitosan gels bind minerals in the intestines, which is an undesirable biochemical effect, a lack of absorption of minerals occurs. In the study, all blood parameters remained within their normal ranges. All experimental groups showed a significant decrease in serum Na levels at the end of the study. Serum K levels decreased after 21 days in all Zn added groups, but raised to their normal levels at the end of the study. The addition of Zn plus inulin to diets caused increase in CK and creatinine, significantly. Additional researches are needed to elucidate the negative effects and the action mechanisms of Zn plus inulin on muscle tissue in broilers. This study may also show the potential protective effect of COS on liver enzymes, and COS may play a role in modulation of liver enzymes.