Artificial Reproduction of Blue Bream (Ballerus ballerus L.) as a Conservative Method under Controlled Conditions

Abstract

The blue bream Ballerus ballerus (L.) is one of two species of the Ballerus genus occurring in Europe. The biotechnology for its reproduction under controlled conditions needs to be developed to conserve its local populations. Therefore, a range of experiments were performed to obtain valuable gametes from blue bream following hormonal stimulation with carp pituitary homogenate (CPH), Ovopel and Ovaprim. CPH and Ovopel were injected twice and Ovaprim—once, under a pectoral fin. The spawners were inspected 12 h after the last injection, and the gametes were collected. Eggs were collected from spawning females and fertilized with sperm from three males. The smallest number of ovulating blue bream (four females) was obtained from individuals stimulated with Ovaprim. There were six to nine ovulating females in the other groups, accounting for 60–90% of the females in the respective groups. The latency period was the shortest in the spawners stimulated with Ovopel. The fish in this group ovulated 14 h after the hormonal injection. Spawning was synchronized and all females spawned simultaneously. The highest average weight of eggs per fish (75.4 g) was obtained from the females stimulated with Ovopel, whereas the individuals stimulated with Ovaprim provided the smallest average amount of eggs (49.5 g). The study showed that blue bream spawners are not very sensitive to reproduction-related handling under controlled conditions.

Effect of Different Water Salinities on the Larvae of the Blue Bream Ballerus ballerus (Linnaeus, 1758) during Rearing

“…The fish were caught using pond equipment—fyke nets and wontons. The blue bream larvae were from reproduction carried out under controlled conditions [ 25 ].…”

“…In the case of the blue bream, an effective method for its reproduction and optimal feeding during rearing under controlled conditions has already been developed [ 25 , 26 ]. Research on the effects of various factors on the growth and survival of blue bream larvae has been launched due to the lack of relevant data in the literature.…”

Impact of replacing natural food with commercial feed on the growth and survival of blue bream larvae (Ballerus ballerus) under controlled conditions

“…The blue bream spawners originated from Lake D¹bie (Poland). Sex products were obtained under controlled conditions following hormonal stimulation (Piech and Kujawa 2021). The water temperature during egg incubation was 19°C ± 0.5.…”