Furthermore, associated with this abnormal orientation of the eye is a progressive degeneration of the retina – the light-sensitive tissue of the eyes that converts light to nerve impulses to enable vision. The fish, therefore, have abnormal vision with no, or limited, vision in the direction in which they normally swim. This feature is what gives this breed of fish their name: they are said to be looking up at the stars. In these fish, the eyes do not face sideways as in normal fish, but are rotated through approximately 90 degrees such that their vision is directed upwards. These features would not exist in wild populations as individuals with such disabilities would fail to survive and would not pass on these genes to subsequent generations. They are characterised by two anatomical abnormalities that cause significant disability but which have been maintained by artificial selection and captive care. Celestial eye goldfish are of a type that seems to have existed for around a hundred years (Koh 1963) but which has grown in popularity in the last 80 years. Goldfish ( Carassius auratus auratus) are a domesticated form of the common carp originating in Eurasia: the Chinese Crucian carp “Gibelio” ( Carassius auratus gibelio) (Komiyama et al 2009).
![celestial goldfish standard of perfection celestial goldfish standard of perfection](https://i.pinimg.com/originals/ad/b4/c6/adb4c67075907c0003de85b9688e2ad7.jpg)
Prospective goldfish owners should avoid purchase of these fish.įor further details about this condition, please click on the following:
![celestial goldfish standard of perfection celestial goldfish standard of perfection](https://azure.wgp-cdn.co.uk/app-practicalfishkeeping/news/img-132.png)
Methods and prospects for elimination of the problemįor welfare reasons, it seems reasonable to propose that the breed of Celestial-eye goldfish should not be perpetuated. How do you know if an animal is a carrier or likely to become affected?Īll Celestial eyed goldfish are affected but there is variation among them in the degree of mal-position of the eyes.Ĩ. The absence of the fin and the presence of the eye defects are probably independent of one another, the fin having been lost historically prior to the eye defect arising (Koh 1963, Komiyama et al 2009).ħ. The genes that cause the absence of the dorsal fin are also unknown but it is likely that they are similar to those that underlie the lack of fin in the bubble-eye goldfish. The genetic defects that cause the abnormal eye position may be linked to the progressive retinal degeneration and blindness that is seen in this breed, as they occur concurrently but the genes involved are not known. The abnormal eye position and lack of dorsal fin are clearly apparent. The absence of a dorsal fin causes severe welfare problems associated with impaired movement from birth. It is difficult to assess the welfare effects of the abnormal eye orientation and lack of dorsal fin but it seems reasonable to propose that these handicaps affect the animals' welfare, as they become blind and have impaired movement, which make activities such as feeding and swimming difficult for these fish (Matsumura et al 1981, 1982, Sakaue et al 1987, Kolle & Hoffmann 1997, ).Ĭelestial eye goldfish do not have the abnormal eye orientation at birth but develop it over the first six months from hatching (Matsumura et al 1981, 1982, Sakaue et al 1987).
![celestial goldfish standard of perfection celestial goldfish standard of perfection](http://www.bristol-aquarists.org.uk/goldfish/aa_standards/celestial-standard-2.gif)
It is the first abnormality that is the primary cause of our concern for welfare in this fish. The second feature is lack of a dorsal fin (a fin on the middle of the back). Associated with this malposition of the eyes is degeneration of the retina – the layer of the eyes that is sensitive to light and converts it into neurological activity (Matsumura et al 1981, 1982, Sakaue et al 1987).
![celestial goldfish standard of perfection celestial goldfish standard of perfection](https://www.goldfisho.com/wp-content/uploads/2016/05/lionhead-goldfish-.jpg)
The first is that the abnormal orientation/position of their eyes, which are rotated through 90 degrees, so that their vision is directed upwards. (for more information click on the links below)Ĭelestial eye goldfish are characterised by two anatomical abnormalities that cause significant disability to the fish. It is hard to judge the welfare effects of these conditions but it seems reasonable to suppose that disrupted vision is not consistent with good welfare. All fish of this breed are affected but there is some variation in the severity between individuals. In association with this, there is degeneration of the retinas – the light sensitive parts of the eyes – resulting in progressive blindness. Outline : The eye position of Celestial eye goldfish develops abnormally during the six months from hatching such that the eyes rotate through 90 degrees to end up facing upwards (facing the heavens – hence the fish's name). Related terms : retinal degeneration, Stargazer goldfish Celestial Eye Goldfish Celestial Eye GoldfishĬondition: abnormal eye position, blindness and absence of dorsal fin