ASSESSING THE GROWTH PERFORMANCE, STRESS, BLOOD METABOLITES, LEG BONE QUALITY AND WELFARE OF BROILER CHICKEN FED ON YEAST TREATED DIET

Abstract

An experiment was conducted to assess the effect of yeast (Saccharomyces cerevisiae) supplemented diets on the productive performance, welfare, leg bone health and quality, and profitability of broiler chickens. The study investigated the growth performance measures such as live weight (LW), feed intake (FI), and feed conversion ratio (FCR), viability, as well as stress and fear responses, blood biochemical profiles, leg bone health, profitability and overall welfare. A total of 108-day-old Cobb-500 broiler chicks was randomly assigned to four dietary treatment groups (T0, T1, T3, and T4), each treatment replicated three times with nine chicks per replication in a Completely Randomized Design (CRD). The chicks were weighed first and then uniformly distributed into twelve pens or cages. From day one to day 30, the birds were fed mash diets by including yeast supplement adlibitum. Broiler was reared in battery cages from d1-30 days under similar feeding, housing, lighting and environmental condition. All of the experimental diets were iso-caloric and iso-nitrogenous, and they contained 0.05% of yeast (T1), 0.07% (T2), 0.09% (T3), and a control diet (T0) with no yeast. To measure physiological reactions to the dietary treatments, information was gathered on blood serum parameters, gait scoring (GS), latency-to-sit (LTS), important growth performance indicators (FI, LW, and FCR), and welfare assessments. According to the findings, the group that received 700 mg/kg supplements (T2) gained the maximum body weight, demonstrating better LW (P<0.05) and FI without affecting FCR and viability. The results of serum biochemical examination showed that T2 had higher blood glucose levels (P<0.05) without influencing (P>0.05) other blood parameters studied herein. There was a marginal significant (P=0.058) improvement in the GS test without affecting (P>0.05) fear-related behavior i.e. tonic immobility (TI). Yeast supplementation had a positive effect on the latency to sit (LTS) test. Significantly (P<0.05) the highest LTS score (2.53) was found for the birds fed T2 diet. Significantly (P<0.05) the highest profit margin and lowest production cost were found in the broiler fed T2 diet as well. The study concludes that while feeding additives based on yeast-treated diet could help broilers grow and become more resilient, and the impact of yeast supplemental diet (T2) on the weight gain, feed consumption, leg bone health, and profitability are clear. So, it could be concluded that broiler fed on yeast supplemental diet (T2) at the rate of 0.07% could improve productivity with better utilization of feed and leg bone health which can be implemented in commercial flocks for better profitability.