[Effects of probiotic and calcium butyrate on production performance, egg quality, blood parameters and immune response in laying hens]

ABSTRACT

The effects of probiotic and calcium butyrate [Ca-butyrate] as feed additives on performance and immune response have been shown in laying hens. The aim of the present study was to investigate the effects of different levels of probiotic and Ca-butyrate on performance, egg quality, blood parameters and immune response in laying hens. Two hundred and eighty eight Hy-Line W-36 hens [62 to 70 wks of age] were used in a 2×3 factorial arrangement with three levels of probiotic [0, 0.07 and 0.01 percent] and two levels of Ca-butyrate [0 and 0.1 percent] in a completely randomized design of 6 treatments and 8 replicates. The results showed that feed intake, feed conversion ratio, egg production, shape index, yolk index, haugh unit, egg weight and specific gravity were not affected by probiotic and Ca-butyrate. While egg weight and egg mass were significantly [p<0.05] increased using probiotic compared with the control diet, such an effect was not observed due to Ca-butyrate addition. However, shell thickness showed significant increase [p<0.05] in response to Ca-butyrate. The interaction between different levels of probiotic and Ca-butyrate was only significant for feed conversion ratio [p<0.05]. Antibody titer against sheep red blood cell [SRBC] was not affected [p>0.05] by experimental treatments. The concentration of serum albumin was significantly increased [p<0.05] by adding probiotic and Ca-butyrate to feed. Furthermore, significant increase [p<0.05] in total serum protein was pronounced in response to probiotic and Ca-butyrate. However, other serum metabolites [total calcium, triglycerides and cholesterol concentrations] were not affected by treatments. The relative percentage of heterophiles and heterophiles to lymphocytes ratio were significantly decreased [p<0.05] using probiotic. Dietary probiotic and Ca-butyrate can be considered as additives to improve immune responses in laying hens