INCREASING OF STORAGE PERIOD ALTERS EMBRYO DEVELOPMENT AND HATCHING CHARACTERISTICS OF PEKIN DUCK EGGS

This research was performed to determine the effects of storage period on embryo development and hatching characteristics in Pekin ducks. A total of 360 Pekin duck eggs was divided into four groups as 5-7 d, 8-10 d, 11-13 d and 14-16 d storage period and each group were stored at 15-18 ºC. Eggs were incubated at 37,5°C and a relative humidity of 55 to 60% during the first 24 days of incubation. These eggs were transferred into hatching machine for the last four days. A hatcher temperature of 37.0°C and a relative humidity of 72% were provided during hatching period. The effects of storage period on embryo development, embryonic mortality, hatchability of fertile eggs, hatchability of total eggs and chick hatching weight were significant (P 0.01). Results showed that a longer storage period caused a decline in yolk absorption and therefore decline of embryo growth parameters including body weight and length during incubation period. Hatchability declined with increasing of storage duration, and a storage period less than 7 d appeared to be the best for maximum hatchability. Egg weight loss increased with increased storage length (P 0.01), and the chick weight tended to decline in relation with storage period longer than 5-7 days.