Koi Digestion Explained | How Do Koi Digest Their Food
Koi Food and Koi Digestion
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Koi’s metabolism is excellent at using up what it needs and dispelling the rest.
The super efficient way a Koi’s digestive system absorbs essential nutrients is
one of the factors why the species has survived for thousands of years,
relatively unchanged.
Over the centuries Koi carp have evolved to be able to effectively digest a wide variety of different food substances that are under normal conditions difficult to break down. The food substances that wild Koi digest and assimilate are totally different from the specifically engineered Koi Food Products commercially available on-line or through pet stores and garden centres.
The processes involved in a Koi carp’s digestive system consist of both physical and mechanical processes. In the wild, Koi need to be opportunistic so they have developed highly sensitive mechanisms for detecting the presence of food. They are equipped with very sensitive food receptors that help them to quickly and easily sense the presence of food. With excellently tuned senses (sight, smell, and sound) they are very accurately able to decide whether or not they are about to be fed. Have you ever noticed that they seem to be a lot more energetic when you step near to the pond?
What Happens To Food As A Koi Eats?
As foreign substances enter into the Koi’s mouth they come into contact with the pharyngeal teeth that have been designed to grind down food into smaller particles before passing into its digestive tract. As the pharyngeal teeth work away, anything deemed unpalatable or unable to be digested is spat out.
As food passes from the Koi carp’s buccal cavity to its intestines it passes down the oesophagus. The lining of the oesophagus contains tiny cells called cilia and goblet cells that effectively aid the smooth passing of food down the tract into the anterior intestines. It is in the intestines where the ground down food is assimilated (digested) into the Koi’s bloodstream.
Unlike many mammals, including humans a Koi carp does not have a stomach. Due to the super efficient way food is ground down by the pharyngeal teeth there is no need for digestive stomach acid and enzymes such as pepsin; normally required to break down protein. Also because Koi are omnivores they are quite capable of living without eating meat, unlike carnivorous fish species.
So is Koi Food Good for Koi?
It depends upon which side of the fence you sit on. Overall, however, commercially manufactured Koi fish food has been designed to reduce the amount of waste that is released into a pond environment and not necessarily to utilise the digestive process of a Koi to its maximum. Many modern day fish food formulations are designed to encourage maximum growth in the shortest period of time, to encourage extreme colouring etc. So this begs the question “Are we actually doing more harm than good by feeding Koi commercially developed Koi foods instead of foods found in their natural habitat?”
On the other hand it can also be argued that by feeding your Koi a diet that is made from the finest ingredients and contains the prerequisite amount of vitamins and supplements you are in fact encouraging them to remain healthy and therefore resistant to Pond Fish Diseases...