%0 Journal Article %T The Effects of Boron (Orthoboric Acid) Supplementation Into Diets of Hens During Late Laying Period on Performance and Some Serum Parameters %A Hacer KAYA %J - %D 2019 %X This study was carried out to determine the effects of boron (orthoboric acid) addition to the diets of hens in the late laying period on performance and some serum parameters. Two hundred eighty-eight Lohman commercial laying hens which are 62 weeks old were fed with 0, 50, 75, and 150 mg/kg of B for 12 weeks. The research was carried out in 18 replicates, and four laying hens were used for each replicate. During the research, 16-hour lighting was applied and feed and water were given as ad-libitum. Supplementation of different level of B did not alter the live weight change and average egg weight from performance characteristics, but egg production increased and also feed efficiency and daily feed intake reduced (P<0.01). Serum glucose, cholesterol, triglycerides, creatinine, total and direct bilirubin values were not affected by additional B. While addition of B into the diets of laying hens did not affect the outcomes of serum alkaline phosphatase (ALP), aspartate amino transaminase (AST) and gamma glutamyl transaminase (GGT) enzyme activities (P>0.05), but alanin amino transaminase (ALT) was affected by Boron (P<0.05). It is concluded that in order to have a positive effect on performance of laying hens in the late laying period, 50 mg/kg B supplementation is adequate and may be suggested %K Yumurtac£¿ tavuk %K Bor %K Performans %K Serum Parametreleri %U http://dergipark.org.tr/yyutbd/issue/44253/490702