THE EFFECTS OF EXOGENOUS COBALT ADDITION TO DIET ON HATCHING PERFORMANCE AND EGG CHARACTERISTICS OF BREEDER JAPANESE QUAILS (Coturnix coturnix japonica)

This study was carried out to determine the effects of exogenous cobalt addition to diet on hatching performance (fertility rate, hatchability, time of hatch, embryo deaths) and egg characteristics of breeder Japanese quails (Coturnix coturnix japonica). In the present study, a total of 180 breeder Japanese quails (Coturnix coturnix japonica) (9 week-old age; 60 male+120 female) were randomly distributed into 12 replicates with 5 male +10 female per pen. The experimental groups were as follow: Ration with exogenous cobalt (treatment) and ration without exogenous cobalt (control). The experiment has been lasted for 5 weeks and the diets provided for ad-libitum during the study. Eggs were collected 2 times a day throughout last week of the study. The hatching eggs were stored for 7 days (at 18 oC and 84 % relative humidity) and set to the incubator according to experimental procedure. The control group (n= 320) and the treatment group (n=320) as totally 640 eggs were used for two groups. There were no found significantly differences between the groups for fertility rate, hatchability of fertile eggs, early and late embryonic mortalities and egg characteristics, but there were found significantly differences between the groups for cumulative hatching times (P 0.05).