Laying, egg quality and blood profile of native hens

The objective of this study was to assess egg quality parameters for the whole laying period depending on oviposition time and breed of Czech and Slovak native breeds of laying hens. Besides, to determine the differences between selected breeds in laying pattern, related to the oviposition place. Furthermore, biochemical blood parameters were measured at the end of the study. A total of 60 pullets at the age of 20 weeks were divided according to the breed. Each treatment consisted of 3 replications of 10 laying hens. The eggs were collected every day, at 6:00, 10:00 and 14:00 and the amount of eggs was recorded for each oviposition time interval (from 14:00 to 5:59, from 6:00 to 9:59 and from 10:00 to 13:59). Moreover, the oviposition place (inside and outside the nest) and the amount of eggs in particular place were recorded. In addition, blood samples were collected. Significantly heavier eggs were laid between 10:00 and 13:59 than between 6:00 and 9:59 h (52.44 vs. 51.39 g, resp.). Haugh units were highest in eggs from Czech golden spotted hens that were laid between 6:00 and 9:59 h and in eggs from Oravka hens that were laid between 6:00 and 9:59 h and between 10:00 and 13:59 h. Significantly lower content of yolk cholesterol was found in Czech golden spotted hens compared to Oravka hens (10.64 vs. 11.22 mg/g, resp.). The Czech golden spotted hens had significantly higher level of glucose in blood serum than Oravka hens (16.47 vs. 14.03 mmol/l, resp.). The Czech golden spotted hens, gene reserve of the Czech Republic, are not yet sufficiently described in scientific literature, which highlights the importance of this study.