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The global shrimp industry has experienced phenomenal growth over the last twenty-two years generating more than 730,000 metric tons of farm cultured product annually. This industry represents a market value exceeding US$3.7-4.5 billion ($5.00-$6.00/kg) ex-farm. In the early 1990’s, this rapid growth began to slow. Reasons for decline include lack of knowledge about farming techniques, poor farm management practices, degradation of environment/water quality through industrial pollution/discharge, and (most importantly), shrimp disease.

An article by C.G. Lundin of the World Bank addressed global shrimp disease and concluded that at an average price of US$5.00/kg for heads-on shrimp and total disease-related losses of 540,000 metric tons, the total loss based on 1994 data would be US$3.0 billion. This indicates a very significant problem that has implications for the wellbeing of millions of people in developing countries whose livelihood depends on this industry. Although recovering somewhat, the total losses from disease for all of Asia are estimated to be well over US$1.0 billion in 1997 (and over $140 million in the Americas). Disease has caused an 11% drop in the yearly harvest total from 1996 and indicates that in all probability the global production of shrimp from aquaculture will not meet expectations for industry growth or consumer demand in the coming years unless resistance to disease is achieved.

Aquaculture is agriculture. Experience and results from breeding and genetic selection programs for agricultural animals and fish (salmon) over the last fifty years have not been transferred to the marine shrimp culture sector. A remarkable increase in productivity and growing efficiency characterize these other sectors as matured and efficient industries. For example, since the 1940’s, the average number of eggs laid per year by a hen has increased from 120 to more than 320; the average milk production per cow in single lactation of 305 days increased from 2,000 kgs to over 5,000 kgs; and, the average daily gain in the pig industry has increased from 450 grams to over 800 grams (in the last 30 years). For salmon, phenotypic and genetic selection has reduced time to achieve market weight by over 30% with a parallel decrease of maintenance requirements (feed, labor, fuel, etc.) by over 25%. Experience and results from breeding and genetic selection programs for agricultural animals and fish (salmon) over the last fifty years have not been transferred to the marine shrimp culture sector. A remarkable increase in productivity and growing efficiency characterize these other sectors as matured and efficient industries. For example, since the 1940’s, the average number of eggs laid per year by a hen has increased from 120 to more than 320; the average milk production per cow in single lactation of 305 days increased from 2,000 kgs to over 5,000 kgs; and, the average daily gain in the pig industry has increased from 450 grams to over 800 grams (in the last 30 years). For salmon, phenotypic and genetic selection has reduced time to achieve market weight by over 30% with a parallel decrease of maintenance requirements (feed, labor, fuel, etc.) by over 25%.

Shrimp farming already consumes more than 1.3 million hectares of land and is suffering from unprecedented environmental pressure to clean up its damaging methodology. Production increases in shrimp farming over the past ten years have been primarily due to tremendous increases in pond area rather than increased output per land area. Further expansion and productivity gains will most likely result from intensification brought about through improvements in nutrition and breeding programs.

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Breeding programs may take one of three forms or a combination of methods.

1. Phenotypic programs Phenotypic programs are an age-old approach based upon cross breeding individuals that display the desirable traits we choose. While this method works most of the time, it is not foolproof generation after generation and the effect of inbreeding is unknown until it appears. Most of all, however, is that long term phenotypic selection reduces the pool of bio-diversity from most captive populations.
2. Genotypic programs Genotypic programs are new to aquaculture and have their longest history with salmon and oyster culture. The approach is still in its infancy since gene functions in most species are unknown or have not been identified. This science involves the location of genes, DNA structure or decoding the information contained within the genomic realm. Such information is then used for selective breeding programs to produce progeny enriched for Quantitative Trait Loci (QTL or desired traits).
3. Transgenic programs involve the transplanting of genes or gene segments from one or more species or genera or families of organisms to create a hybrid organism. Technically, these new Genetically Modified Organisms (GMO’s) retain desired characteristics reflective of the QTL’s from which they were borrowed. A lot of discussion exists regarding this approach in terms of its moral, safety, and control issues, consumption, and environmental impact. involve the transplanting of genes or gene segments from one or more species or genera or families of organisms to create a hybrid organism. Technically, these new Genetically Modified Organisms (GMO’s) retain desired characteristics reflective of the QTL’s from which they were borrowed. A lot of discussion exists regarding this approach in terms of its moral, safety, and control issues, consumption, and environmental impact.