68 March 2012 identified on the Andaman and Nicobar Islands and hatchery facilities at the Andhra Pradesh Shrimp Seed Production and Research Centre (TASPARC) and the Orissa Shrimp Seed Production Supply and Research Centre (OSSPARC) will be testing the SPF broodstock in a commercial production environment. Production of SPF Shrimp Major elements of an SPF process include the capture of apparently healthy wild stock from areas of low disease prevalence followed by individual primary quarantine where the shrimp can be individually screened for specific pathogens and the contaminated individuals destroyed. The shrimp are then transferred to secondary quarantine where they are reared to broodstock size and monitored regularly. The disease-free broodstock are then transferred to the breeding center for production of multiple families from different sources. Larvae are then reared in bio secure hatcheries from the selected families. Any infected stock detected through continual monitoring are immediately discarded. For development of SPR lines of broodstock P. monodon, the primary steps are similar to those for the SPF program. However, a more rigorous genetic selection program utilizing a greater number of families to select for desirable traits is required. Whichever programme is selected; the development of SPF and/ or SPR lines of P. monodon should be regarded as a long-term investment. It requires absolute control on all aspects of culture on a continuous basis, highly trained scientific personnel, the highest standards of discipline and team work, specialized training for staff and continuous laboratory analysis. Advantages of SPF Specific pathogen-free animals offer an advantage to a country introducing a species for the first time as it offers some assurance that the imported animals will not introduce the listed pathogens to native species. However, SPF stocks may harbor non‐specified pathogens and this should be taken into account, inasmuch as it can pose a risk when the animals are under stress. With regard to shrimp culture, biosecurity systems are adopted to overcome a threat of disease outbreaks. The main concepts of biosecurity systems are to exclude pathogens and aid eradication if they occur. Specific pathogen-free stock is one of the major components considered in any biosecurity system, because the specific pathogen can be eliminated and contamination minimized. Specific pathogen-free animals are extremely useful for basic and applied science research, especially to immunological studies and vaccine trials, because the listed interfering pathogens can be ruled out. The SPF animals are also essential for other bioassay; for instance a study of shrimp viral diseases, where the shrimp cell line is not available, the pathogen free animals are needed for bioassay study. Limitations of SPF Shrimp All pathogens that pose a major threat need to be reliably diagnosed and physically excluded from the facility. However, it must be remembered that the shrimp could still be infected with a pathogen not included in the list. Offspring of SPF shrimp are not SPF unless they are produced and maintained at a biosecure SPF facility. Once they leave that facility, they can no longer be termed SPF. It should not be forgotten that domestication of P. monodon is far more difficult than working with L. vannamei. Because maturation of P. monodon in captivity is very difficult, a much longer holding period is required until they reach a viable size. Risks in SPF The major concern of SPF stock is the potential problems caused by inbreeding and genetic deterioration. This may pose problems like reduction in disease tolerance, growth and other developmental abnormalities. Inasmuch the SPF animals are cultured under hygienic condition, their acquired immunity is very low. Thus, SPF stock may not perform well under non‐biosecure or outdoor open culture operations. Specific pathogen-free animals are only free from tested specific pathogens, however the unknown pathogens are usually overlooked. Mutation of specific pathogens commonly occurs, especially in viral diseases. This means that although the monitoring program is active, the pathogenic agent may be missed out. This hidden risk can, consequently, pose a threat to the health status of the animal. Notes 1Laboratory of Aquaculture & Artemia Reference Center, Ghent University, Belgium 2Central Institute of Fisheries Education, Versova, Mumbai-400061, India 3College of Fisheries, Central Agricultural University, Lembucherra, Tripura-799210, India *Correspondence: scmandal02@gmail.com, (+91) 9402169213 (Mobile), 3812865291 (Fax) Advertisers’ Index AQUA 2012 43 AQUACULTURE AMERICA 2013 53 Aquaculture Association of Canada 38 Aquaculture Systems Technology 35 Aquaculture Without Frontiers 51 Aquafauna Biomarine 11 Aquatic Eco-Systems, Inc. Back Cover Australasian Aquaculture 2012 17 Australian Government NMIT 5 Cargill Empyreal 75 25 Emperor Aquatics 34 Extru-Tech, Inc. 21 Firestone Specialty Products Inside Front Cover Northern Aquaculture 31 Novus Aquaculture Inside Back Cover USAS Sponsored Publications 69 WAS Future Meetings 63 WAS Online Store 55
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