Sperm Quality and Cryopreservation in Teleost: Effect of Seminal Plasma Component and Climate Change

Abstract

The cryopreservation of semen from neotropical fish is an important tool for aquaculture, being necessary to establish cryogenic protocols for most native species. This research aimed to determine the influence of seminal plasma as a constituent of the cryoprotective solution on the cryopreservation sperm and of sperm subpopulation structure of the cryopreserved-thawed Pseudoplatystoma reticulatum semen. As cryoprotective solutions were used: T1 = 5% glucose + 10% methanol; T2 = T1 + 30% of P. reticulatum natural seminal plasma e; T3 = T1 + 30% artificial seminal plasma. The data were analyzed by the sperm analysis program (CASA), and a Principal Component Analysis (PCA) was applied. DNA damage was evaluated using the comet assay. There was a statistically significant difference in the variables of Total Motility (MOT) and Progressive Motility (PM) between T1 and T3, with no significant difference between these and T2. The fertilization test showed statistical differences between T3 and Control (fresh sperm), T2 and T1. In the evaluation of DNA, the three treatments showed significant differences, with T2 being the most effective in protecting against DNA damage. The PCA analysis showed that the FERT and seminal quality variables MOT and MP better represented T1. Three subpopulations were present for the cryopreservedthawed sperm, SP1 (fast-linear), SP2 (fast-non-linear), and SP3 (slow-linear).The simple combination of methanol (10%) and glucose (5%) was the most effective treatment for maintaining fast and linear subpopulations. The treatment supplemented with seminal artificial plasma did not show effective results in the protection of the spermatozoa of the species Therefore, we can 48 suggest T1 whit a high degree of protection in the cryopreservation of P. reticulatum sperm.