THE EFFECT OF NATURAL ZEOLITE DIETARY SUPPLEMENTATION ON THE EGG QUALITY OF JAPANESE QUAILS (Coturnix japonica) DURING THE LAYING PERIOD

Abstract

The effect of supplementing natural zeolite (NZ) on the laying characteristics and on the internal and external egg quality during laying period of Japanese quails was studied. The laying and average eggs per female were lower in control (C) and the Z1 experimental groups (1% NZ) compare with the Z2 experimental group (2% NZ). The significant effect of the NZ addition in comparison with the C was found in the eggshell weight and yolk index. The eggshell weight of C (1.10±0.01 g) was significantly lower than Z1 (1.18±0.01 g). The quails of Z2 had significantly lower egg weight than Z1. The average egg weight was significantly affected by diet (P≤0.05) and also by age of quails (P≤0.001). At the beginning of the laying, the weight of the eggs (age 1) was significantly lower (12.07±0.12 g at the beginning, 12.38±0.12 g in the middle and 13.38±0.12 g in the end) (P≤0.001). The albumen weight and Haugh unit were significantly influenced by the age of the females. The albumen weight increased with female age (from 6.88 to 8.10±0.09 g). The HU was significantly lower (89.52±0.30) at the age 1 than in age 2 (90.50±0.30) and age 3 (90.57±0.30) (P≤0.05). The yolk index was significantly affected by both diet and age of animals. The significant difference was between C and Z1 (P≤0.05). The highest yolk index was found in youngest female (P≤0.01). The egg quality was mainly affected by age of females. Diet affected investigated traits to a smaller extent.