The effect of composition feed mixtures on curve of hens laying intensity

Abstract

The experiment was done in the experimental station ÚKZÚZ Havlíčkův Brod. There were four experimental groups (N1, N2, N3, N4) of laying hens and weekly laying intensity was observed. Hybrid ISA BROWN was used in the experiment, 405 hens in each group. The laying intensity was observed from the start of laying for 44 weeks. During laying four different diets were fed to laying hens (N1 – control group with fish meal, N2 – control group containing only of plant protein sources, N3 – experimental group with higher content of rapeseed, N4 – experimental group containing treated rapeseed). Yang model was used for the evaluation of laying curves and we found following parameters of the curves:Yang model N1: y = 97.28 * e – 0.004 * t / [1 + e – 2.054 (t – 2.549)] R2 = 0.97Yang model N2: y = 98.29 * e – 0.006 * t / [1 + e – 2.071 (t – 2.668)] R2 = 0.96Yang model N3: y = 98.49 * e – 0.005 * t / [1 + e – 1.856 (t – 2.568)] R2 = 0.97Yang model N4: y = 98.55 * e – 0.005 * t / [1 + e – 2.251 (t – 2.615)]. R2 = 0.97The results document that experimental treatments had small effect on the parameters of laying curves. It means that rapeseed had only small effect on the laying intensity and also the elimination of animal protein from the diet for laying hens had not effect on laying intensity. On the base of our results we estimated the standard equation for evaluation of laying curve:Yang model: y = 98.15 * e – 0.005 * t / [1 + e – 2.058 (t – 2.601)]. R2 = 0.99This equation can be used as standard for evaluation of laying intensity after experimental treatments or for evaluation of laying intensity of different hybrids.

Keywords

• laying intensity
• Yang model
• curve of laying intensity
• rapeseed