Introduction to Fish Parasites and Diseases
Parasitic diseases of fishes (Fish parasites and diseases) are usually encountered more often than microbial diseases. From 30 to 50 percent of the cases received at several fish disease diagnostic laboratories involve parasites. Host reaction to parasitic invasion is highly variable.
The severity of a parasite epizootic may be related to environmental factors; host condition, age, and size; and population density. Bacteria pathogens associated with fish into two: the non- indigenous bacteria pathogen and the indigenous bacteria pathogens.
The non-indigenous pathogen contaminate fish or fish’s habitat in one way or the other and the pathogens include Clostridium botulinum, Listeria monocytogenes, Staphylococcus aureus, Salmonella species, Shigalla species, Escherichia coli, etc. The indigenous bacteria pathogens are those naturally living in the fish’s habitat.
Read Also : The External Anatomy of a Bony Fish
Procedure
Microscopic inspection of smeared slides (e.g. slime or wound)
Microscopic Examination Bacteriological examination is completed by a microscopic search for bacteria, in spoiled cans directly upon sampling or after incubation.
Usually a wet preparation of smeared contents examined under phase contrast microscope is sufficient to detect microorganisms.
Identification of associated pathogenic organism (bacteria, fungus, protozoa)
Collect the infected parts of the fish aseptically by using sterile forceps and scissors.
Homogenized collected sample in sterile mortar and pestle using phosphate buffer as solvent.
Serially diluted homogenized samples up to 10-6.
Pour one millilitre of diluted sample from each dilution into sterile petri dishes followed by sterilized molten agar medium
After solidification, were inverted all the plates and incubated in a thermostat incubator to allow the growth of bacteria.
After incubation, the colonies appeared on the respective agar plates
Read Also : Introduction to Fisheries Ecology
Finally, the cultures were stored in respective agar slants for further use and identification using microscope.
Methods for application of anti-bacterials to fish (Haya et al., 2005)
| Method of application | Comments | |||
| Oral route (on food) | Needs palatable components; environmental pollution | minimal | risk | of |
| Bioencapsulation | Needs palatable compounds; environmental pollution | minimal | risk | of |
| Bath | Need for a fairly lengthy exposure to the compound, which must be soluble or capable of being adequately dispersed; problem of the disposal of spent drug | |||
| Dip | Brief immersion in a compound, which must be soluble or capable of being adequately dispersed; problem of disposal of the dilute compound | |||
| Flush | Compound added to a fish holding facility for brief exposure to fish; must be soluble or capable of being adequately dispersed; poses a problem of environmental pollution | |||
| Injection | Feasible for only large and/or valuable fish; usually requires prior anaesthesia; slow; negligible risk of environmental pollution | |||
| Topical application | Feasible for the treatment of ulcers on valuable/pet fish |
In summary, diseases and parasitic problems could constitute significant economic losses in fish production if not controlled, thus the need to continue monitoring its prevalence.
Ability to identify associated pathogenic organism in the ecosystem and apply antibacterial of methods is critical to sustainable fisheries management.
Read Also : Sources and Classification of Hazardous Waste
Do you have any question, suggestion or other contributions? kindly use the comment box provided below for all your contributions. You are also encouraged to please kindly share this article with others you feel can benefit from this information if found useful enough as we may not be able to reach everyone at the same time. Thank you so much for sharing!
Do you have any questions, suggestions, or other contributions? Kindly use the comment box provided below for all your contributions. You are also encouraged to please kindly share this article with others you feel can benefit from this information if found useful enough as we may not be able to reach everyone at the same time. Thank you so much for sharing!
Have you visited our Market Place Today? Follow this link to visit Agric4profits.com Market Place now to check out our affordable products & services that might interest you and solve your current needs at a very cheap price.
