On the record of pug- headedness in cultured Atlantic salmon, Salmo salar Linnaeus, 1758 ( Salmoniformes, Salmonidae) from Norway

摘要

Fish developmental anomalies occur in hatchery-raised and wild ?sh populations. Dawson (1964, 1966, 1971) prepared comprehensive bibliographies of reported abnormalities. Pugheadedness is an anomalous condition in ?sh that has been reported in a broad variety of ?sh groups (Manusueti, 1960; Dawson, 1964, 1966, 1971; Warlen, 1969; Dawson and Heal, 1971; Nakamura, 1977; Shari? et al., 1986; Al-Hassan and Na’ama, 1988; Jawad and Hosie, 2007). The condition a?ects the skeletal formation of the head, particularly that of the upper jaw, resulting in an abnormally shorter upper jaw in relation to the lower jaw