The effects of different levels of green grape (Vitis vinifera L.) leaves on performance, egg traits and blood metabolites of laying hens

Abstract

Introduction: An experiment was conducted to evaluate the effects of using different
levels of green grape leaves on performance, egg quality, blood biochemical and
immunity parameters of laying hens.
Materials and Methods: Experiment was carried out in a completely randomized
design with 192 laying hens (Hy LineW-36) in 4 treatments and 4 replicates from 65
to 72 weeks. Experimental diets included: 1) control group with no green grape leaves,
in 2 until 4 treatments the level of green grape leaves were 1.5, 3, and 4.5%.
Results: Adding green grape leaves into laying hens diets significantly affected their
performance, egg quality traits, blood biochemical and immunity parameters (P<0.05).
The highest amounts of egg production percentage, egg mass, feed intake, the best feed
conversion ratio and the lowest price for production per kilogram of egg, the lowest
level of blood uric acid were resulted by using 3% green grape leaves. Yolk color index,
eggshell, albumin and egg yolk weights improved by using 4% green grape leaves,
whereas the eggshell thickness decreased.
Conclusion: In contrast with control group, the count of white blood cells by using
green grape leaves increased. The overall results showed that using 3% green grape
leaves significantly improved the performance and reduced the feed price for
production per kilogram of egg in laying hens.