Productive and reproductive parameters of the first selective breeding generation of Antonino-Zozulenets intrabreed types of Ukrainian frame and scaly carp breeds

Abstract. The history of growing Antonino-Zozulenets carp is connected with the intensive development of fish farming in Khmelnytskyi Oblast starting from the 15th century, when the Chernylivka, Kuzmyn and Starokonstantyniv ponds were built. Currently, Antonino-Zozulenets carps are common in fish farms of the Forest Steppe and Polissia zones. The proposed Program for selective-breeding work with genetically isolated broodstocks of these carps in various territorially distant fish farms allowed creating two crossbreed lines. Those are the frame and scaly forms at the Khmelnytskrybhosp PrJSC. The broodstock of this farm consisted of age 6–11 fish and the first selective-breeding generation of 5-year-old females and 4-year-old males. The studies of their productive parameters were carried out using advanced methods in fish farming and ichthyology, used in the international practice. The main method of creating the initial broodstocks was the method of continuously improving (mass) selective breeding based on the assessment of the productivity of carps using a set of characteristics and selection of individuals most adapted to the conditions of cultivation, biologically complete with noticeable changes in useful features. The post-wintering survival rate of 4 and 5-year-old Antonino-Zozulenets carps were in the range of 94.3–97.2%. Between both age categories, individuals with a scaly coating had higher values than the frame individuals. Weight losses were in the range of 9.2‒10.6%. In accordance with the average absolute fecundity at fishery enterprises, first-spawning scaly females were 3.2% superior to the frame females and 6.4% superior to the second-spawning females. The maturity coefficient of the first-time spawners was 11.9‒12.1% and such of the repeat-spawners was 16.2‒16.5%. The fertilization rate and survival rate of free embryos were within the standard range. The mean fertilization rate was 91.3% of the frame carps, 92.6% of the scaly first-spawning carps, and 93.1% and 92.8% of the repeat-spawning carps, respectively. The survival rate of free embryos and three-day-old larvae exceeded 80%. According to the average ejaculate volume ‒ 7.6 cm3 of the frame and 19.8 cm3 of scaly first-spawning males, the sperm activity was 57.2 and 68.3 s, respectively. Thus, this parameter exceeded such of the repeat-spawning males, being 12.6% higher than the frame fish and 17.6% higher than the scaly males, with the average ejaculate volume of 18.3 and 21.2 cm3, respectively. During natural spawning, an average of 153.6‒175.6 thousand eggs were produced by the first-time spawning females and 242.5‒248.6 thousand larvae were obtained from the repeat-spawning females, which was 17.4% greater than the average value of the original broodstock – 200 thousand larvae.