Reproductive performance of carp, Catla catla (Ham.), reared on a formulated diet with PUFA supplementation

Effect of dietary supplementation of n‐3 and n‐6 polyunsaturated fatty acids (PUFA) on reproductive performances in both sexes of an Indian major carp, Catla catla (Ham.), were investigated in terms of sperm quality, spawning response, fecundity and spawn recovery over a consecutive 2‐year period. Sperm count and spermatocrit value were in the range of 3.2–3.8 × 10⁷ ml⁻¹ and 80–82%, respectively, in fish fed the PUFA‐enriched test diet, and significantly higher (P < 0.01) than in fish fed control diet (2.3–2.5 × 10⁷ ml⁻¹ and 64–70%). Spawning response in the test diet group was quite high (96%) compared to 76% in the control. Egg and larval quality were superior in the test diet group as evidenced by the significantly higher fertilization rate and larval survival in the range of 91–92% and 93.3%, respectively. Fatty acid profile of fertilized eggs and larvae showed that the quantities of 18:3 (n‐3), 20:5 (n‐3) and 22:6 (n‐3) were significantly (P < 0.01) increased in the test group while 18:1, 18:2 (n‐6) and 20:4 (n‐6) remained at higher levels in control. The results indicated that enrichment of n‐3 PUFA in the broodfish diet not only improved the quality of eggs and larvae in terms of recovery, but also enhanced the physiological response of broodfish to induced spawning. Oil enrichment in the broodfish diet should therefore be mandatory to ensure the optimum n‐3 PUFA content for warmwater carp for quality seed production.