The threat of harmful pathogens:
Sustainable seafood that includes, Salmon, Halibut, Sea Bream, Cobia, Rainbow Trout, and Oysters are all valuable commodities threatened by harmful pathogen infestation. But they’re not the only ones. Public exhibits of fish, invertebrates, mammals, reptiles, and birds—all living examples of our natural world—are also in constant danger of coming in contact with harmful pathogens.
It’s no secret that our world is faced with declining water purity and availability. This, combined with increased disease outbreaks, has resulted in continued pollution and the introduction of new waterborne pathogens to natural waters.
There is a solution... UV Disinfection.
The chart on the next page lists the most common pathogens found in Aquaculture and identifies their required Fluence (UV dose) for inactivation.
Harmful Waterborne Pathogens:
Aquaculture has used UV disinfection to control harmful waterborne pathogens for many years, but few design-consultants, purchasers, and operators truly understand UV’s limitations well enough to use it successfully and cost-effectively. To achieve successful UV disinfection one must apply it correctly! The first step in applying UV disinfection correctly is to familiarize yourself with the targeted pathogens. This helps to establish the application’s UV disinfection requirements. Keep in mind, no two pathogens are exactly alike and all require their own specific UV-C dose.
Microorganism Complex Life Cycle
The diagram above demonstrates the complex life cycle of the warm water protozoa Cryptocaryon (marine white spot). The diagram illustrates the four life-cycle stages of this lethal protozoan. It reveals the microorganism’s physical size and actual life-span based of its life-cycle stage. The free-swimming Tomite excyst or infective stage, when the microorganism is smallest (25-60 µm), is the life-cycle stage where UV Disinfection is most effective.
Harmful Pathogens Associated With Aquaculture:
|» ALGAE||UV DOSE|
|Chlorella vulgaris||22 mJ/cm2|
|Aeromonas salmonicida||3.6 mJ/cm2 (log-3)|
|Pseudomonas fluorescens (fin rot)||11 mJ/cm2 (log-3)|
|Listeria monocytogenes||16 mJ/cm2 (log-5)|
|Streptococcus sp. (seawater)||20 mJ/cm2|
|Bacillus subtilis (spores)||22 mJ/cm2 (log-3)|
|Vibrio anguillarum||30 mJ/cm2|
|Yersinia ruckeri||30 mJ/cm2|
|BKD (Bacterial Kidney Disease)||60 mJ/cm2 (estimate)|
(Salmonid Bacterial Coldwater Disease)
|Vibrio sp. (oyster)||155 mJ/cm2|
|Saprolegnia diclina (zoospores)||40 mJ/cm2 - 170 mJ/cm2|
|Sarcina lutea (Micrococcus luteus)||26 mJ/cm2 (log-3)|
|Ceratomyxa shasta||30 mJ/cm2 (log-3)|
|Perkinsus marinus (dermo disease)||30 mJ/cm2|
|Trichodina sp.||35 mJ/cm2 (log-3)|
|Myxobolus cerebralis (TAMs, Whirling Disease)||40 mJ/cm2|
|Ichthyophthirius multifiliis (freshwater white spot)||100 mJ/cm2|
|Amyloodinium ocellatum||105 mJ/cm2|
|Trichodina nigra||159 mJ/cm2|
|Cryptocaryon irritans (marine white spot)||280 mJ/cm2|
|Costia necatrix||318 mJ/cm2 (log-3)|
|KHV (koi herpesvirus)||4 mJ/cm2|
|ISA (Infectious Salmon Anemia)||8 mJ/cm2|
|CCV (Channel Catfish Virus)||20 mJ/cm2|
|IHNV (Infectious Hematopoietic Necrosis/CHAB)||20 mJ/cm2|
|OMV (Oncorhynchus masou Virus)||20 mJ/cm2|
|IHNV (Infectious Hematopoietic Necrosis/RTTO)||30 mJ/cm2|
|VHS (Viral Hemorrhagic septicemia)||32 mJ/cm2|
|CSV (Chum Salmon Virus)||100 mJ/cm2|
|AHNV (Atlantic Halibut Nodavirus)||105 mJ/cm2|
|IPNV (Infectious Pancreatic Necrosis Virus)||246 mJ/cm2|
|Log-1 = 90% • Log-2 = 99% • Log-3 = 99.9% • Log-4 = 99.99% • Log-5 = 99.999%|
UV doses not accompanied by a specific log value, should be considered a minimal dosage. The listed data was collected from various sources and Pentair Aquatic Eco-Systems, Inc. does not accept any responsibility for the accuracy of this information. This information is meant to be a guideline and should be used as such.