Effect of technological systems for laying hens housing on selected indicators of eggshell quality | Vplyv niektorých technologických systémov ustajnenia nosníc na vybrané ukazovatele kvality škrupiny vajec
2010
Gálik, R., Slovenská poľnohospodárska univ. v Nitre (Slovak Republic). Technická fakulta | Švenková, J. | Poláková, Z. | Boďo, Š
The paper deals with evaluation of some technological systems for housing of laying hens (conventional and enriched cages) on selected indicators of eggshell quality. Mathematical and statistical methods were used for analyses. Measurements were conducted under laboratory conditions. The laying hens housed in both technological housing systems belonged to the same hybrid ISA BROWN. Both measured groups of birds had the same age and were fed by the same feedstuff. Significance of differences between the eggshell thickness, deformation of eggshell as well as power needed for destruction of eggshell were analyzed by Student t-test in both groups. Nonlinear function (parabola) was used for explanation of relationships obtained in conventional and enriched cages. Following results have been verified. The deformation of eggshell increases and the thickness of eggshell decreases until the age of laying hen of 300 days. After this age these factors develop in opposite way (deformation of eggshell decreases and the thickness of eggshell increases). The relationship has been observed while breeding period. For explanation of relationship between power needed for destruction of eggshell and age of laying hens the linear regression line was used in both assessed systems. Based on the equations for conventional and enriched cages (y=36.31-0.0315x and y=3.942-0.0282x) it can be concluded that the power needed for destruction of eggshell is lower every day by 0.0315 N and 0.028 N respectively. The regression coefficient (R2) of 0.7905 and 0.5586 was achieved for this relationship. Also, negative relationship of these factors was achieved in both technological systems.
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