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Quantitative Genetics The basic dynamics of Breeding Programs
The Genetics sub-discipline that addresses and seeks the productive improvement of animals and plants is referred to as Quantitative. Its basic equation is of the form Progress/Year = (i * h * sA) / t where sA is the genetic variability available to the program, i the selection intensity exercised, h the accuracy of the selection criteria, and t the interval between generations.
	SyAqua’s breeding program is based on a family structure, with integral preservation of all pedigree information linking families and selected brood-stock. This is a sine qua nom attribute of any serious, long-term, and sustainable genetic effort. It is the only system that allows for inbreeding management, to be able to select for carcass and meat quality traits (% tail, % meat, proximate composition, and properties such as texture, appeal, flavor, etc.), to be able to select for disease resistance and commercial performance while preserving a rigorous bio-security and high health status for the selected brood-stock and for the commercial PLs, and because it is also the only avenue that makes it possible for molecular genetic tools to be used as selection aids.
Regarding genetic variability (sA), SyAqua’s breeding program has experienced a tremendous qualitative leap in August 2004 with the importation of SyAqua genetic lines from their genetic nucleus in Hawaii. The plans are on track for a breeding program with 300 families run in 5 Batches every three months reducing generation intervals to near optimum.

SyAqua has incorporated several stocks and lines of distinct origins, which are invaluable and unique genetic resources. They are applying them to the main breeding program through systematic strategies that also target new and innovative commercial breeding schemes modeled after the hybrid system of breeding corn and other plants. This widely increases the genetic variability available to the program and they combine it with a remarkable intensification of the selection pressures exercised ( i ) which leads, according to the formula above, to new rates of genetic progress that are much faster than those previously accomplished or achieved in the shrimp industry.
Other essential components and objectives of SyAqua’s current breeding program are the management of inbreeding through computer algorithms that take into consideration and process all pedigree information available (Optimal Contributions Theory), and the uniformity of the commercial products, to be attained through breeding schemes of the hybrid model, schemes that also provide assurances of genetic protection for SyAqua’s improved stocks and investment efforts. Animals from each of the 300 families annually produced are elastomer-tagged, and tested in the Genetic Nucleus program in Thailand (GN), under conditions of complete bio-security. Data is collected from commercial ponds, to evaluate the genetic merit of the families under those environments and commercial production systems that are the only real target of the improvement programs (ie: the levels of productivity on the farms and ponds of the shrimp producers. The evaluation of GxE interactions are key for the commercial success of the program. Animals that leave the GN never return, since the GN is maintained under a system of total and strict bio-security, by which those brood-stock finally selected were never exposed to opportunities for contamination in infected or less bio-secure environments, being also regularly tested and monitored for various diseases.
	Animals are tagged when they are about 2 g, and then performance tested for growth and survival rates up to harvest weights. Thousands of animals are elastomer-tagged and at harvest all shrimp are individually weighed and the survival rate obtained for each family, both for the GN and in the commercial animals. These phenotypes are then subjected to sophisticated statistical analyses (BLUP), incorporating all pedigree information, required fixed effects and covariates, allowing for the generation of BLUP estimates of genetic merit for growth and survival rates for all our tested families. The genetic merit estimates are combined through a Selection Index aiming at a balanced genetic progress for the two traits, growth and survival, both essential for what really matters to the shrimp producer – biomass produced/ m2, and brood-stock selections finally implemented. A summary of how SyAqua implements its Genetic improvement program is represented in Figure 1.
*The result of this complex breeding program is extremely fast genetic improvement that will make available ever improving products for the benefit shrimp farmers and the processing industry.*

Quantitative Genetics

The basic dynamics of Breeding Programs

The Genetics sub-discipline that addresses and seeks the productive improvement of animals and plants is referred to as Quantitative. Its basic equation is of the form

Progress/Year = (i * h * sA) / t

where sA is the genetic variability available to the program, i the selection intensity exercised, h the accuracy of the selection criteria, and t the interval between generations.

SyAqua’s breeding program is based on a family structure, with integral preservation of all pedigree information linking families and selected brood-stock. This is a sine qua nom attribute of any serious, long-term, and sustainable genetic effort. It is the only system that allows for inbreeding management, to be able to select for carcass and meat quality traits (% tail, % meat, proximate composition, and properties such as texture, appeal, flavor, etc.), to be able to select for disease resistance and commercial performance while preserving a rigorous bio-security and high health status for the selected brood-stock and for the commercial PLs, and because it is also the only avenue that makes it possible for molecular genetic tools to be used as selection aids.

Regarding genetic variability (sA), SyAqua’s breeding program has experienced a tremendous qualitative leap in August 2004 with the importation of SyAqua genetic lines from their genetic nucleus in Hawaii. The plans are on track for a breeding program with 300 families run in 5 Batches every three months reducing generation intervals to near optimum.

SyAqua has incorporated several stocks and lines of distinct origins, which are invaluable and unique genetic resources. They are applying them to the main breeding program through systematic strategies that also target new and innovative commercial breeding schemes modeled after the hybrid system of breeding corn and other plants. This widely increases the genetic variability available to the program and they combine it with a remarkable intensification of the selection pressures exercised ( i ) which leads, according to the formula above, to new rates of genetic progress that are much faster than those previously accomplished or achieved in the shrimp industry.

Other essential components and objectives of SyAqua’s current breeding program are the management of inbreeding through computer algorithms that take into consideration and process all pedigree information available (Optimal Contributions Theory), and the uniformity of the commercial products, to be attained through breeding schemes of the hybrid model, schemes that also provide assurances of genetic protection for SyAqua’s improved stocks and investment efforts.

Animals from each of the 300 families annually produced are elastomer-tagged, and tested in the Genetic Nucleus program in Thailand (GN), under conditions of complete bio-security. Data is collected from commercial ponds, to evaluate the genetic merit of the families under those environments and commercial production systems that are the only real target of the improvement programs (ie: the levels of productivity on the farms and ponds of the shrimp producers. The evaluation of GxE interactions are key for the commercial success of the program. Animals that leave the GN never return, since the GN is maintained under a system of total and strict bio-security, by which those brood-stock finally selected were never exposed to opportunities for contamination in infected or less bio-secure environments, being also regularly tested and monitored for various diseases.

Animals are tagged when they are about 2 g, and then performance tested for growth and survival rates up to harvest weights. Thousands of animals are elastomer-tagged and at harvest all shrimp are individually weighed and the survival rate obtained for each family, both for the GN and in the commercial animals. These phenotypes are then subjected to sophisticated statistical analyses (BLUP), incorporating all pedigree information, required fixed effects and covariates, allowing for the generation of BLUP estimates of genetic merit for growth and survival rates for all our tested families. The genetic merit estimates are combined through a Selection Index aiming at a balanced genetic progress for the two traits, growth and survival, both essential for what really matters to the shrimp producer – biomass produced/ m2, and brood-stock selections finally implemented. A summary of how SyAqua implements its Genetic improvement program is represented in Figure 1.

The result of this complex breeding program is extremely fast genetic improvement that will make available ever improving products for the benefit shrimp farmers and the processing industry.