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The present experiment was conducted to breed a vulnerable cyprinid fish, Dawkinsiarohani (Rohan's barb), in captivity through hormonal inducement using one of the reproductive synthetic hormones WOVA‐FH, since these fish did not breed spontaneously in captivity. The experiment was conducted in 500‐L capacity fibre‐reinforced plastic tanks with breeding hapa. The male (length 8.5 ± 1.5 cm and weight of 12 ± 2 g) and female (length 9.5 ± 2 cm and weight of 15 ± 1.5 g) brooders were injected intramuscularly with variable dose of WOVA‐FH and released into the breeding hapa at 2:1 (male:female) ratio. Varied doses of WOVA‐FH used for fish in the present study refer to 0.3 ml/kg (T1), 0.5 ml/kg (T2), 0.7 ml/kg (T3), 1.0 ml/kg (T4) and 0.0 ml/kg T0 (control). General courtship behaviour was observed in hormone‐induced fish after 6–9 h after injection. Breeding was observed in all the treatment group fish except T0 (control groups). Success of spawning, fertilization and hatching rate varied depending on the dose of hormone. Significantly higher fecundity (1142.3 ± 40.20 eggs/female), fertilization rate (90.2 ± 0.67%) and hatching rate (88.92 ± 0.25%) were achieved in fish injected with 0.7 ml/kg for female and 0.3 ml/kg for male per kg body weight compared to other hormone treatment groups. Dosage levels influence the percentage of spawning, egg stripping, fertilization and hatching rate. The present study successfully standardized the dose for induced breeding of D. rohani. The standardized breeding technology will be helpful in breeding, conservation and propagation of the endemic indigenous ornamental fish, D. rohani. [ABSTRACT FROM AUTHOR]

The one‐stripe spiny eel (Macrognathus aral, Bloch & Schneider, 1801) under the family Mastacembelidae, a native ornamental fish, were collected from the freshwater ponds and canals of West Bengal, with a purpose to raise the colony as ornamental fish broodstock. During acclimatization, fish were found to be lethargic and reluctant to consume feed followed by the appearance of deep wounds and red patches on the ventral part of the body surface. There was a mortality of 40.49% of affected fish within the next 48 hours. Post‐mortem examinations revealed the presence of metacercariae inside the body cavity and on internal organs, spreading up to the buccal cavity. The abundance of the parasite was 15 to 36 numbers per fish. The length of the metacercaria varied from 5.2 mm to 9.8 mm. The metacercariae were identified as Clinostomum complanatum by light microscopy. Further, molecular confirmation of identification was done using PCR amplification and sequencing of the 18S RNA gene. This is the first report of metacercarial infestation of Clinostomum complanatum with molecular confirmation in indigenous M. aral with high ornamental value. [ABSTRACT FROM AUTHOR]