Epidemiological approach to aquatic animal health management: opportunities and challenges for developing countries to increase aquatic production through aquaculture

doi:10.1016/j.prevetmed.2004.11.004

Preventive Veterinary Medicine

Volume 67, Issues 2–3, February 2005, Pages 117-124

https://doi.org/10.1016/j.prevetmed.2004.11.004 Get rights and content

Abstract

Aquaculture appears to have strongest potential to meet the increasing demands for aquatic products in most regions of the world. The world population is on the increase, as is the demand for aquatic food products. Production from capture fisheries at a global level is levelling off. Potential contributions from aquaculture to local food security, livelihoods and nutrition can be highly significant, especially in many remote and resource-poor rural areas. One of the major constraints to aquaculture production is the losses due to diseases. Over the decades, the sector has faced significant problems with disease outbreaks and epidemics which caused significant economic losses.

The use of sound epidemiological principles and logical and science-based approach to identify and manage risks comprise two of the most important components of an effective biosecurity program. The maintenance of effective biosecurity in aquaculture is becoming more and more essential. There will be more demand for aquatic animal epidemiologists as well as epidemiological tools/resources in the region. The use of epidemiology will significantly improve health management, risk analysis and disease control.

Although there are clear limitations and complications in the use of epidemiology for controlling aquatic animal pathogens, some positive results have recently emerged from a series of studies and trials to control diseases affecting the small-scale shrimp farming sector in southern India. This paper summarises the results of one such study which emphasizes the significant benefit of close collaboration with farmers, both individually and as groups, and capacity and awareness building among them and the importance of understanding the risk factors and implementing better management practices.

Section snippets

Aquaculture as a global source of nutritious food

Aquaculture is the fastest growing food-producing sector in the world. A great proportion (over 90%) of this production comes from the developing world. In contrast to terrestrial farming systems, where the bulk of global production is based on a limited number of animal and plant species, the aquaculture sector comprises of over 230 different species. This large number of species cultivated reflects the diversity of the sector, particularly the wide variety of candidate species cultivated and

Diseases and health as a constraint to aquaculture production

Although production of aquatic food through aquaculture is the fastest growing food-production sector in the world, diseases are a primary constraint to the growth of the aquaculture sector in many parts of the world. A multitude of factors has contributed to the health problems currently faced by aquaculture. Over the past three decades, aquaculture has expanded, intensified, and diversified, based heavily on movements of live aquatic animals and animal products (broodstock, seed, and feed).

Epidemiological approach to aquatic health management

Controlling aquatic animal disease can be problematic due to many factors. These include the great diversity of species cultured, the range and complexity of environments used, the nature of containment, the intensity of practice, the type of management and the variety of diseases affecting aquatic animals. Profitability in aquaculture production can be affected even by small percentage decreases in production especially when large number of animals are involved.

One of the most effective

Experiences with small-scale shrimp aquaculture

Shrimp farming is an important economic activity in India. An initiative on shrimp disease control was started in 2000 by the marine products export development authority (MPEDA), ministry of commerce and industry, Government of India with technical assistance from the network of aquaculture centres in Asia-Pacific (NACA). The initiative has made significant progress and contributed to knowledge of avenues for reducing losses in shrimp aquaculture. As follow-up to this initiative, Andhra

Study design, demonstration and implementation

During 2002, demonstrations were conducted in few selected private farms which involved on-farm testing of BMPs developed in 2001, and monitoring and evaluation to understand benefits and constraints, and to widely disseminate information on risk management strategies to farmers. Improved pond level risk management practices led to improvements in both profits and productivity and in demonstration farms, returns shifted from a loss in 80% of ponds in 2001 to a profit in 80% of ponds in 2002.

Shrimp health management and epidemiology

Shrimp health management practices, including risk assessment and management were incorporated into the BMPs developed in consultation with local farmers. The BMPs included three main management strategies: (a) pond bottom preparation and water management prior to stocking; (b) seed selection and stocking; (c) post stocking management. The simple BMPs used during the study are given below:

(a)
pond bottom preparation and water management prior to stocking:
- •
  sludge removal and disposal away from the

Acknowledgements

The author wishes to acknowledge MPEDA and NACA for providing permission to use the experimental data. Special appreciation goes to Mr. Arun Padiyar, Dr. Michael Phillips, Mr. Mongkhon Primphon, Dr. C.V. Mohan, Mr. Vishnu Bhat, Mr V.S. VS Rao and Mr. G. Ravi for their untiring work which lead to success of this study.

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Epidemiological approach to aquatic animal health management: opportunities and challenges for developing countries to increase aquatic production through aquaculture

Abstract

Section snippets

Aquaculture as a global source of nutritious food

Diseases and health as a constraint to aquaculture production

Epidemiological approach to aquatic health management

Experiences with small-scale shrimp aquaculture

Study design, demonstration and implementation

Shrimp health management and epidemiology

Acknowledgements

A brief overview of disease problems in the culture of marine finfishes in east and southeast Asia, pp. 9–31

Risk factors associated with white spot syndrome virus infection in a Vietnamese rice-shrimp farming system

Dis. Aquat. Org.

Epizootic Ulcerative Syndrome (EUS) Technical Handbook

Usefulness of dead shrimp specimens in studying the epidemiology of white spot syndrome virus (WSSV) and chronic bacterial infection

Dis. Aquat. Org.