Effect of dietary supplementation with natural zeolite on the performance and quality characteristics of eggs from laying hens
Postgraduate Thesis – Author: Efthymiu, Maria Konstantinou; Supervisor: Dotas, Dimitrios, Aristotle University of Thessaloniki, School of Agriculture, 2010.
The aim of this research project was to investigate the effect of adding natural zeolite to the diet on the productive traits and characteristics of eggs laid by laying hens.The experimental group consisted of 96 Isa Brown laying hens, aged 28 weeks and with an average body weight of 1,870 g at the start of the experiment. The hens were housed in cage batteries in a controlled environment and allocated to four dietary treatments (M, Z1, Z2 and Z3), in accordance with a completely randomised experimental design (C.R.). Each treatment comprised four replicates, each consisting of six hens. Each replicate consisted of two adjacent shallow pens, each housing three hens.During the experiment, the hens in group M were fed a standard maize- and soya-based diet for laying hens, whilst the hens in treatment groups Z1, Z2 and Z3 were fed the same diet to which natural zeolite had been added at ratios of 1 per cent, 2 per cent and 3 per cent, respectively. Total egg production for each replicate was measured on a daily basis. Feed intake for each replicate was determined weekly, whilst the change in the hens’ average body weight for each treatment was measured at the start (day 1), at the midpoint (day 28) and at the end (day 56) of the experimental period. Once a week, two eggs were randomly selected from each replicate (32 eggs in total) and weighed separately. Of the 32 eggs, 16 were selected (one egg from each replicate), and their quality characteristics were assessed. The results of the research study showed that the addition of natural zeolite to the feed of laying hens did not significantly affect the hens’ productive performance or the quality characteristics of the eggs.