The aquarium fish industry is under increased scrutiny due to its potential to introduce or spread aquatic diseases. Currently, there are a number of initiatives around the globe that have or propose to place increased regulation on the industry to address real or perceived threats to their native or cultured species from foreign or introduced diseases. We have also begun to recognize these risks. In fact 20 years ago, Svein Fossa, the past president of OFI, noted “ hardly any industry is involved with the dispersal of species to the scale of the ornamental fish industry.” When Svein said this he was actually referring to the risk of the introduction of alien fish and invertebrate species to new ecosystems but he could have just as easily been referring to the risk of introduction and spread of disease agents. He correctly suggested that the industry has a “special responsibility” to do all we can to avoid the release, introduction and spread of aquatic disease agents.
Consequently, I feel the industry must constantly reassess its approaches to health management with the goals of striving to continually improve health management and reduce the risks for spreading or introducing disease to their facilities and regions. We must be pragmatic when assessing health management throughout our global chains of custody. We should recognize that while there are many examples of excellent health management within our industry it is not universal. There are still many regions in which we continue to have examples of intermittent or ineffective health management and a lack of accountability throughout these chains of custody.
I firmly believe that it is always better if our industry identifies its own issues and develops its own solutions rather that waiting for the regulatory bodies to impose regulations us. With this background in mind, I’d like to review some of the important aspects of fish health management and perhaps begin a discussion of some of the ways you might think about implementing these concepts within your facility. In the future I will address some of the specifics of a fish health management program.
What is fish health management?
Fish health management is all of the procedures and practices within a facility or supply chain designed to prevent disease among captive aquatic animals. A good fish health management program should have two important goals:
1) Maximize the immunocompetence (the health of the immune system) of the fish populations. This is usually achieved through excellent animal husbandry and stress management.
2) Reducing or eliminating potential disease agents or disease causing factors throughout the supply chain and/or within a facility.
A good fish health management plan begins before the fish are acquired. You need to ensure that you are to receive healthy fish and that you understand the water quality parameters at the source facility and have a plan to properly acclimate the fish to your water parameters,
Providing excellent husbandry once fish have arrived at your facility is important to ensure that animals are well equipped to resist disease agents that are often ubiquitous within many holding systems. Development of a comprehensive biosecurity program is an essential aspect for achieving this goal.
What is biosecurity?
Biosecurity consists of the practices and procedures used to prevent the introduction, emergence, spread, and persistence of disease agents and disease causing factors throughout the supply chain and within holding facilities. It is the lynchpin for any successful fish health management program. There are standard approaches to developing a biosecurity program but development and implementation of each biosecurity program will be unique to the specific facility or supply chain.
How do I develop a biosecurity program?
The first step to developing an effective biosecurity program is to identify the risks within your supply chain and/or facility. There are generally five risks to disease introduction and spread for any aquatic animal holding facility: the animals, water, food, people and equipment. Each of these factors is potential sources of disease introduction or spread within a facility. Disease may enter a facility within the fish themselves, via contaminated feeds, on equipment that is brought into the facility without proper cleaning and disinfection, on employees, visitors or customers and within incoming system or shipping water. Improperly treated effluent water may spread disease outside the facility.
What are the key components of a biosecurity plan?
A typical biosecurity program focuses on two major components: pathogen exclusion, the procedures implemented to prevent pathogen introduction to a facility, and pathogen containment, the procedures implemented to prevent pathogen spread within a facility. Today I’ll provide an overview of the principles of pathogen exclusion.
Pathogen exclusion
These are the procedures implemented to prevent pathogen introduction to a facility. These procedures typically focus on reducing the risks associated with various potential routes of disease entry and establishing an effective quarantine protocol for all new introductions. The five most important pathways for pathogen entry into a facility are:
1. The Fish and invertebrates arriving at your facility can all carry potential pathogens.
2. The water coming into a facility may also contain potential pathogens. This would include the shipping water, the water source for a facility.
3. Food is a potential source of pathogen entry. Food can become contaminated with toxins or pathogens, it can spoil if improperly stored and live foods can contain pathogens, which can result in an introduction of disease.
4. People are another potential source of disease agent introduction. Employees or customers may bring in pathogens from outside the facility. The development of specific protocols to reduce these risks is key to effective pathogen exclusion.
5. Equipment can also be a factor for pathogen introduction. Equipment moved between facilities or improperly cleaned and disinfected between uses can pose a tremendous risk for disease introduction.
Quarantine: Quarantine is the final critical component of pathogen exclusion for your facility. The major role of quarantine is to prevent the introduction of pathogens directly into your retail population by separating new arrivals from the existing population and allowing a predetermined period of time for observations and disease screening. Quarantine also provides for the important process of acclimation of fish to new water conditions, new husbandry protocols, and new feeds. Furthermore, the quarantine system and quarantine period allows time for the fish immune system to recuperate from the stresses of transport and handling. Figure 1 outlines the key components of a quarantine protocol.
In summary:
1. Good fish health management maximizes immunocompetence.
2. Good fish health management reduces or eliminates disease agents or disease causing factors.
3. Begin by identifying the risks of pathogen introduction to your fish facility.
4. Good fish Health management and biosecurity practices focuses on pathogen exclusion AND pathogen containment.
5. Pathogen containment practices begins before the fish are purchased, by selecting healthy fish.
6. Pathogen containment practices include acclimation and quarantine protocols.
In the next posts I’ll go into a bit more depth about selecting healthy fish, proper acclimation and quarantine.
Dr. Tim
