The effectiveness of pituitary extract from Crucian carp (Carassius auratus Linnaes, 1758) in inducing ovulation in Veil tail gold fish (Carrassius auratus gibelio) and its effects on egg quality

Abstract

The effectiveness of pituitary extract from Cruc ian carp (Carassius auratus Linnaes 1758) in inducing ovulation in Veil T ail Gold Fish (Carassius auratus gibelio Bloch 1783), was examined and th e effect of maternal hormone treatment on egg quality in two types of fertilizat ion (fertilization in aquarium and artificial fertilization), were evaluated in 22 degree C temperature. Fish were injected intrapritoneally with three doses of, 2, 3 and 4mg/kg B.W pituitary extract (PE). With increasing of pituitary dose, pract ical fecundity also increased from 1775 in control fish to 3201 in fish with 4mg /kg B.W of PE. Mean time to ovulation was reduced significantly (P<0.05) from 13 2h in control fish to 13h in fish with 4mg/kg B.W. Ovulated eggs from fish injec ted with 4mg/kg B.W of PE had lower fertility and hatching rates compared to egg s from fish injected with lower doses and the control fish. The methods of ferti lization had no significant effect on the egg quality. In conclusion, the result s of this study showed that the pituitary extract of Crucian carp is effective i n inducing and shortening of ovulation of Veil Tail Gold Fish and the suggested dose for this species is 3mg/kg B.W.