Background:

Artificial breeding of Clarias gariepinus entails sacrificing the male, which is necessary to know the semen’s physical features and variations for preservation during the pre-breeding stage, and its utilization for the breeding stage.

Aim.

To characterize the morphometric changes and seminal quality of Clarias gariepinus during the pre-breeding (PRS) and breeding (BS) stages.

Methods:

A number of 42 breeding males were evaluated in the two stages, using weight (LW) (kg), length (LT) (cm), gonadal weight (GW), and seminal vesicles (SVW) (g), condition factor (CF), gonadosomatic index (GSI), and seminal-somatic vesicles index (S-SVI). Samples from testicle’s semen (TS) and seminal plasma/testicle’s semen (SP-TS) were collected. Their color, testicle seminal volume (TSV), and seminal plasma volume (SPV) (ml), motility, sperm activation time (SAT) (sec), sperm concentration (SC) (x109 sptz/ml), and spermatocrits (SPCTO) (5), were evaluated. An analysis of variance of the variables was conducted, considering the time as the variation source, along with a Pearson correlation analysis.

Results:

The LW, GW, and SGI increased significantly (P<0.05) during the BS). The TSV and SPV were lower in the PBS, with a higher SC. The creamy semen showed high SC (21.14 ± 2.90 x 109 sptz/ml) and SPCTO (19.50 ± 1.24 %), whose correlation was moderate (r=0.58, P<0.001).

Conclusions

The breeding males with low SGI and aqueous semen should be rejected due to their low cellular density. SC can be predicted through the spermatocrit, so that high-quality semen can be available during the PBS through conservation.