the effects of apple pulp and probiotic on performance, egg quality traits and blood parameters of laying hens

introduction apple is one of the most important fruits that is produced in the large amount in iran. it is a good source of vitamins and minerals and active fiber. most of the apples that product in iran are use in food industry for producing different kinds of apple juices. after juicing, more than 20% of apple, remain as waste. the remained matter contain considerable amount of vitamins and minerals that usually found in fresh apple, moreover it is rich source of pectin and crude fiber. generally this byproduct discharge to environment and cause some serious environmental problems. it is thought that use of apple pulp as a part of apple waste in laying hens diets not only prevent some environmental problems, but also can improve their performance, egg quality traits, and blood biochemical parameters and reduce the production cost. the current study has been designed to investigate these traits. materials and methods this experiment was carried out on 192 hi-line (w36) laying hens in a completely randomized design as (2*2) factorial arrangement with two levels of apple pulp (0 and 4%) and two levels of probiotic (protexin) (0 and 0.005%) in 4 treatments, 4 replicates and 12 birds per replicate for 12 weeks (65-76 weeks). results and discussion using apple pulp and probiotic in diets improved the egg production performance, egg quality traits and blood parameters of laying hens (p 0.05). probiotic improved egg weight, egg production percentage, egg mass, feed conversion ratio and haugh unit. in interaction effects, using apple pulp and probiotic improved the performance and egg quality traits of laying hens. the highest egg weight, egg production, egg mass and the best feed conversion were obtained with diet containing 4% apple pulp and 0.005% probiotic. also the highest amount of albumin, eggshell thickness and haugh unit were observed with 4% apple pulp and 0.05% probiotic. apple pulp decreased the blood levels of triglyceride, cholesterol and albumin and increased hdl (p>0.05). in interaction effect, using apple pulp with probiotic reduced the amount of triglyceride and albumin meanwhile the amount of blood cholesterol increased (p>0.05). apple pulp contains considerable amount of essentials nutrients such as vitamins and minerals and secondary substances like antioxidants, crude fiber and pectin. use of apple pulp in hens diets improved the digestive tract health and highly amount of these compositions transfer to birds body and improve their performance, egg quality and blood parameters. the high amount of dietary fiber in apple pulp may be the main reason of blood parameters improving. the fibrous diets not only caused the secretion of bile increase but also increased the amount of cholesterol excretion compared to normal condition. probiotic created a good environment in digestive tract by decreasing the population of harmful microorganisms, increasing the number of gram positive microorganisms and reduced ph of digesta in gut which can have positive effects on performance of laying hens. in diets containing probiotic, only productive parameters improved, whereas egg quality and blood biochemical parameters were not affected, meanwhile incorporated probiotic in apple pulp treatments, effectively improved egg quality traits and blood biochemical parameters more than performance. apple pulp contain some composition that their digestion have some difficulties for laying hens, so, incorporation of probiotics such as protexin in diets those containing highly amount of undesirable composition such as fiber and pectin, can have good effects on egg production, egg traits and can improve blood biochemical parameters and be useful for efficient use of apple pulp by hens conclusion it can be resulted that using 4% of apple pulp in laying hens not only had no adverse effects on performance, egg quality traits and blood biochemical parameters, but also could effectively improve most of them, in contrary with more fibrous feeds that increased the amount of feed intake in bird, using 4% apple pulp did not have significant effects on the amount of daily feed intake in laying hens. using 0.005% of probiotic can improve the performance, egg traits and blood parameters in laying hens.