PUFA-enriched experimental diets: a comparison with males fed a wet diet

Ž . Reproductive performance of male European sea bass Dicentrarchus labrax fed a wet diet Ž . WD was compared to that of fish fed two commercial pelleted diet enriched with polyunsatuŽ . Ž . Ž . rated fatty acids PUFAs by the use of Northern hemisphere fish oil ST or tuna orbital oil RO . Broodstock growth, spermiation duration, milt production, milt spermatozoa density, sperm motility, milt lipid composition, and fertilization rates were compared during the reproductive season. RO and ST males exhibited longer spermiation periods producing statistically higher milt volumes and milt spermatozoa densities as compared to WD; no differences in quality or motility of sperm were observed between groups. Although the fertilization rates of RO, ST and WD milt Ž . at 3 and 24 h after fertilization were similar 88–90% , significantly higher rates of embryonic and Ž larval survival were observed at 48 and 72 h after fertilization from eggs fertilized with ST 13.9% . Ž . Ž . and 15.5% and RO milt 20.9% and 20.6% as compared to WD 1.0% and 1.2% . Analysis of milt PUFA profiles revealed several differences between groups. Although total PUFAs were ) Corresponding author. Tel.: q34-964-319500; fax: q34-964-319509. Ž . Ž . E-mail addresses: [email protected] J.F. Asturiano , [email protected] S. Zanuy . 1 Present address: Departamento de Produccion Animal y Ciencia de los Alimentos, Facultad de Ciencias Experimentales y de la Salud, Universidad Cardenal Herrera CEU, Avda. Seminario srn. 46113 Moncada Ž . Ž . Valencia , Spain. Tel.: q34-96-136-9000 ext. 1172 . 0044-8486r01r$ see front matter q2001 Elsevier Science B.V. All rights reserved. Ž . PII: S0044-8486 00 00515-9 ( ) J.F. Asturiano et al.rAquaculture 194 2001 173–190 174 increased in all groups as compared to diet PUFA composition, a greater increase was noted for ST and RO. In January and March, fish fed the WD exhibited more weight gain and attained significantly higher weights, respectively, than RO fish. Results showed that although fish fed the WD displayed increased weight gain, reproductive performance was enhanced in males fed the commercially fabricated diets possibly reflecting benefits of PUFA-enrichment. q 2001 Elsevier Science B.V. All rights reserved.