I've been looking into fish eyes of late and believe they are an important indicator of koi and goldfish health .
When you think it all through their eyes can be very important indeed so lets look at them .
Whilst the over all structure of koi'/goldfishs eyes is similar to that of we humans, there are however some major differences .
A koi/goldfish's eyes differ in that they have an adaption which is unique , in that the lens is attached to the back of the eye by a muscle and a specialist ligament because of this it enables the lens to move both forwards and backwards rather than being stretched in order to fucus light on the back of the retina which is similar to the human eye in that like us it contains both rods and cones that enables it to process both black and white as well as colour images .
Unlike us the intensity and colour spectrum of light experianced by them is very different to what we the humans can see .
What can the eyes tell us ?
Well a healtrhy koi will have a spherical eye with a clear and dark lens anything from the norm in both shape and lustre will show up and can be observed by us on during our routine feeds .
There are a range of health issues that will have an impact on the shape, colour and structure of their eyes
1) Cloudy eye[cornea]
2) Popeye
3) Cloudy eye [lens] possible cateract
4) Bleeding eye
5) Poor eye lustre
6) Deformaty
Reasons for the above
1) a) Trauma [with exessive mucus] b) infection c) enviromental d) parasite
2) a) Envromental b) Gass bubble disease[supersaturaton of air] c) temperature trauma or shock d)trauma to the eye e)Infection [systemic].
3) a) Trauma b) Ntritional c) Parasite[eyeflukes] d) Bright light and genetic factors have been implicated [koi can become completely overwhelmed by any sudden increase in light levels]***Note
4) a) Trauma [such as puncturing] b) [Septicaemia].
5) a) Poor diet [partiulately that of essential fatty acids] c) lack of vitamins
6) a) Nutritional b) enviromental [toxins] c) genetic.
So as you can see there are a number of factors that can cause defects damage etc to a koi/goldfishes eyes .
***Note Eye flukes are a type of parasitical flatworm that are capable of afflicting a koi's eyesite opening them up to attack/ predation note seen in koi ponds that have other fish species in with them
Whist Goldfish can do without eyes in a tank situation thanks to all its other scenses it would be unwise to place either it or a blind koi into fish pond enviroment as they would soon fall foul of predation.
As such the onus is on us to check our fishes eyes every chance we get , we normally use feeding time for this giving the fish a once over not just looking for problems with our fishes eyes but its overall body shape weight etc can be noted at the same time as .
Dave
When you think it all through their eyes can be very important indeed so lets look at them .
Whilst the over all structure of koi'/goldfishs eyes is similar to that of we humans, there are however some major differences .
A koi/goldfish's eyes differ in that they have an adaption which is unique , in that the lens is attached to the back of the eye by a muscle and a specialist ligament because of this it enables the lens to move both forwards and backwards rather than being stretched in order to fucus light on the back of the retina which is similar to the human eye in that like us it contains both rods and cones that enables it to process both black and white as well as colour images .
Unlike us the intensity and colour spectrum of light experianced by them is very different to what we the humans can see .
What can the eyes tell us ?
Well a healtrhy koi will have a spherical eye with a clear and dark lens anything from the norm in both shape and lustre will show up and can be observed by us on during our routine feeds .
There are a range of health issues that will have an impact on the shape, colour and structure of their eyes
1) Cloudy eye[cornea]
2) Popeye
3) Cloudy eye [lens] possible cateract
4) Bleeding eye
5) Poor eye lustre
6) Deformaty
Reasons for the above
1) a) Trauma [with exessive mucus] b) infection c) enviromental d) parasite
2) a) Envromental b) Gass bubble disease[supersaturaton of air] c) temperature trauma or shock d)trauma to the eye e)Infection [systemic].
3) a) Trauma b) Ntritional c) Parasite[eyeflukes] d) Bright light and genetic factors have been implicated [koi can become completely overwhelmed by any sudden increase in light levels]***Note
4) a) Trauma [such as puncturing] b) [Septicaemia].
5) a) Poor diet [partiulately that of essential fatty acids] c) lack of vitamins
6) a) Nutritional b) enviromental [toxins] c) genetic.
So as you can see there are a number of factors that can cause defects damage etc to a koi/goldfishes eyes .
***Note Eye flukes are a type of parasitical flatworm that are capable of afflicting a koi's eyesite opening them up to attack/ predation note seen in koi ponds that have other fish species in with them
Whist Goldfish can do without eyes in a tank situation thanks to all its other scenses it would be unwise to place either it or a blind koi into fish pond enviroment as they would soon fall foul of predation.
As such the onus is on us to check our fishes eyes every chance we get , we normally use feeding time for this giving the fish a once over not just looking for problems with our fishes eyes but its overall body shape weight etc can be noted at the same time as .
Dave