The experiment was conducted to evaluate the influence of strain and age on
some egg quality parameters (egg weight and egg shell strength) of commercial
laying hens. Layers of lines ISA Brown and DeKalb White were examined in
period of nine months. Both lines were at same age (28 weeks) and were
confined in common facility in battery cages. Laying hens were reared and fed
according to standard breeding technology. Once a month 25 eggs of each line
were taken to be examined for eggshell strength and egg weight, or in other
words, total 450 table eggs were tested. Analises were done in Laboratory for
testing egg quality by gaudges Egg Multi Tester EMT 5200 and Egg shell Gauge
(Robotmation Co. Ltd., Tokyo, Japan) which have computerised equipment to
examine quality and physical characteristics of eggs. Statistic analyses on
results were done by computer sub-programme ANOVA and Fisher's LSD test to
determine the level of statistical significant difference between examined
factors. Egg weight was under significant impact of age (P ? 0,05), but not
under the influence of strain, although eggs of ISA Brown line were
insignificantly heavier than eggs of DeKalb White line. Eggs were heaviest at
layers with older age, while they were lightest at younger birds. The results
have shown significant differences (P ? 0,05) in eggshell strength compared
to line influence (genotype) and months of age. Eggs from ISA Brown laying
hens had much better and eggshell strength than those eggs from DeKalb White.
Correlations between eggshell strength and egg weight were with significant
(R < 0,05) negative value, which indicating that with increasing egg weight
decreases of eggshell strength.
Effect of L-Arginine on Productive Performance, Egg Quality Parameters, Blood and Hormone Parameters of Laying Hens in Late-phase of Production
