Seminal vesicle and testis secretions in ž / Heteropneustes fossilis Bloch : composition and effects on sperm motility and fertilization

Ž . Ž . In spawning catfish Heteropneustes fossilis, seminal vesicle SV plasma SVP , testicular Ž . Ž . plasma TP and blood plasma BP all showed considerable differences in physical and chemical Ž . Ž . characteristics. SVP is more viscous 4.61"0.08 centipoise , and its specific gravity 1.06"0.003 Ž y1. and osmolality 277.4"8.32 m osmol kg are significantly higher than BP and TP. SVP has a Ž . near neutral pH 6.99"0.07 . BP is slightly basic and TP is slightly acidic. SVP has significantly qŽ y1. 2qŽ y1. higher concentrations of Na 135.64"15.90 mmol l , Ca 19.80"0.60 mmol l , 2qŽ y1. 2qŽ y1. Ž y1. Mg 1.81"0.08 mmol l and Cu 0.18"0.02 mmol l , proteins 11.50"0.80 g l Ž y1. qŽ and hexosamines 694.68"91.25 mg l than TP, while the concentrations of K 15.30"1.30 y1. 2qŽ y1. Ž y1. Ž mmol l , Zn 0.10"0.02 mmol l , glucose 76.18"24.29 mg l , fructose 333.33" y1. Ž y1 Ž . Ž . 45.64 mg l , lipids in mg l : phospholipids PL , 112.84"18.40; free cholesterol FC , Ž . . Ž y1 109.99"15.45; esterified cholesterol EC , 170.72"10.56 and glycosidases mmol mg protein y1 . h : b-glucuronidase, 7.20"0.56; b-N-acetylglucosaminidase, 83.00"12.29 are similar to TP. Dilution of SV fluid at G400 times with distilled water activated motility of spermatozoa and the motility rate increased with the dilution factor. The duration of motility increased with motility rate up to 600–700 times dilution, but then on, declined sharply. A similar motility behavior was found for TM with the addition of SVP. The fertilization efficiency was evaluated in the presence Ž . of SVP or SV fluid SVF . The addition of freshly collected SVF and SVP increased the fertilization ability of TM from 72.0% to 95.6% and 87.8%, respectively. Pure SVF and SVP ) Corresponding author. Tel.: q91-542-317325; fax: q91-542-317074. Ž . E-mail address: [email protected] K.P. Joy . 0044-8486r01r$ see front matter q2001 Elsevier Science B.V. All rights reserved. Ž . PII: S0044-8486 00 00483-X ( ) I. Chowdhury, K.P. JoyrAquaculture 193 2001 355–371 356 resulted in only 29.6% and 0.0% fertilization, respectively. Heat denaturing abolished the stimulatory effect of SVF or SVP. Storage of spermatozoa in SVF at 48C after dilution with ringer Ž . solution 1:4 displayed varied effects on fertilization of eggs; in SVF groups fertilization Ž . decreased minimally 21.7% on day 12 , but in TM group, it decreased more significantly with the time of storage. q 2001 Elsevier Science B.V. All rights reserved.