Attempts for increasing Astyanax altiparanae spawning rates and percentage of responsive oocytes

Author(s)

Guimaraaes, Daniel ; Ariki, Figueiredo ; de Abreu, Mariana Roza ; Silva, Laiza Maria de Jesus ; Sato, Rafael Tomoda ; Batlouni, Sergio Ricardo

• Document type: Journal article
• Source: Animal Reproduction Science; v. 254, p. 13-pg., 2023-06-07.

Abstract

In this study, we aimed to propose changes in the protocol of cultured Astyanax altiparanae hypophysation to increase the maximum ovulation rate of 60% registered previously. To that two consecutive experiments were conducted. In the first experiment, three carp pituitary homogenate (CPH) doses (3, 6, and 9 mg/kg) were administered in a single injection, while in the second experiment, the 6 mg/kg CPH dose was tested either in single or double injections. In the first experiment, a single injection of 3 mg/kg CPH did not induce final oocyte maturation or spawning, while a dose of 6 mg/kg CPH resulted in an increase in the plasma level of prostaglandin (PGF(2a)) at ovulation. The single higher dose of 9 mg/kg CPH did not improve reproductive performance and even though anticipated the resumption of meiosis it was detrimental to the spawning rate. In the second experiment, the dose of 6 mg/kg CPH fractionated into two injections led to a higher spawning rate, spawning volume per female body mass, frequency of post-ovulatory complexes, and PGF(2a) concentration at ovulation compared to the single injection. The most effective treatment remained the 6 mg/kg of CPH fractionated into two injections, but still providing very low proportion of ovulated females (similar to 40 %). Overall, this study indicates that the spawning protocols for this species need to be improved to induce ovulation in a larger number of females and be more potent in those females that respond positively. (AU)

• FAPESP's process: 16/25988-7 - Induction to final maturation and ovulation of lambari (Astyanax altiparanae) with salmon GnRH analogue
• Grantee: Mariana Roza de Abreu
• Support Opportunities: Scholarships in Brazil - Doctorate