CLONAGEM COMERCIALFlavio Meirelles

This lecture intends to discuss the state of the art of the technology, to approach some problems faced in our experience and, finally, to discuss the possible contribution of the final clonagem, that is, that in that the clones are destined to the production and they are not used as reproducers, for the genetic earnings and for the nuclear genetic selection and citoplasmatica in the animals, with emphasis in the bovine flock. Themes as selection based on characteristics addictive and not addictive, as well as selection or modification citoplasmatica are discussed seeking your possible applications in the future. Abstract

Somatic cell nuclear transfer (animal cloning) i being commercially explored in many countries and species, and thousands of cloned animals have already been produced and delivered to their owners worldwide. The commercial exploration of cloning i contributing to the evolution of the technology, the far the brings funds from of companies to support scientific development, however, other commercial interests challenge the exchange of experiences and knowledge among members of scientifical community.

This talk intends to discuss the state of the art in cloning, to depict adds of the problems seen in our experience and, finally, to discuss the possible contribution of teminal cloning, that means the cloning process in which the cloned animals plows raised exclusively it goes production not it goes reproduction, to the genetic improvement, and nuclei and cytoplasmic genetic selection in animals, with special emphasis in cattle. Selection based in additive and non-additive traits, and cytoplasmic selection or modifications plows discussed focusing their possible applications in the future. Introduction It has been discussing a lot about the evolution of the nucleus transfer in the last decade. Most of those discussions had beginning there are exact 10 years, with the publication of the birth of the sheep Dolly, the first derived mammal of transfer of nucleus of somatic cell (TNCS). Many other animals the posteriori were produced by several laboratories. The possibility to produce identical individuals in the livestock sends to the that we observed in the agriculture, where clones are common. Frequently, in highways, we crossed immense forests of clones of Eucaliptus sp. Then because not to use the clonagem to benefit the animal production? From the end of the decade of 90, many laboratories are applying with success TNCS to produce clones of different species. Some reports show a process walking for a satisfactory efficiency for application in the field, but in most of the cases, the results of TNCS are low, with variable rates of gestation and reduced viability of the born animals. In our works the eficiencica of the process, being observed the rates from birth, it is around 7for the females and 12for the males. Besides, there is adult mortality neonatal among the females, what results in approximately the double of efficiency of the clonagem of males in relation to the clonagem of females. The gestations of those animals are problematic, with frequent presence of disturbances responsible placentarios for high losses in this period. In spite of that, animals clonados are being generated to the thousands, and great part with healthy development. The evolution of that science is, though, of difficult estimate and, at any moment, inside of the close ones ten to twenty years, we can be living an explosion of the commercial clonagem. A first sign of this interest is the recent popularization of a report for the Food and Drug Administration

(FDA) of the USA, affirming, with base in a series of studies, that there is not risk to the health human associate to the consumption of derived products (meat and milk) of bovine clones, when compared to you encourage non clonados. Studies in the species su� have been pointing the same results. Of the genetic point of view, a clone is a nuclear genetic copy. Factors present reprogramadores in the cytoplasm of the o�o, not yet completely known, they are capable to modify the somatic nucleus, turning him/it capable to guarantee the embryonic development and to generate an animal to term. The embryos reconstituted in the clonagem process they inherit components of the receiving o�o that contribute, in way majority or total, with the inheritance citoplasmatica, including the DNA mitocondrial (mtDNA). being like this, it is important to point out that clones are nuclear genetic copies, with possible variations epigen�cas, citoplasmaticas and fenotipicas. Such variations current fenotipicas of the clonagem can be explained being taken into account the effects of the atmosphere, of the receiving ones, and the mechanisms epigen�cos. Nowadays, several companies already produced and they gave animals healthy clonados to your customers. The deprived initiative has been producing, with variable success rate, clones of bovine, ovinos, bovid, swine, equine, canine, felines, and even of wild animals. To growing need of turning the most efficient clonagem has been stimulating companies of the branch they allocate her/it financial resources and qualified labor in the search for aprimoramentos or innovations in the clonagem process. Although it is known that important scientific experiments and consistent progresses have been generated, the diffusion of that knowledge is limited by the commercial interests and for the inherent competitiveness to that market. Certainly, the bovinocultura answers for most of the clones produced commercially. It is difficult to esteem the total number of animals produced for ends you trade; though, an estimate of 2005 indicated 1500 born animals, in the world, until then. In what he/she concerns the production animals, the objectives for clonagem are animal superior for some characteristic specific fenotipica, of high commercial value, of high affective value or of high genetic merit. Of the point of view of animal production, the clonagem process is only justified if the animals go superiors genetically in some characteristics to which were selected. Bulls with discharge differentiate expected of progeny (DEP) and your mothers are good examples of as the clonagem it can accelerate the genetic earnings. However, he/she fits to remind that in the commercial system, the proprietor is who decides the animal to be clonado not always basing your decision on genetic merit. In the quality of example, of the clones produced in the world until the moment, about 100 they are animal with good performance in circumlocution, and there are not evidences that the behavior in the arena is maintained in the clones. The clonagem favored the multiplication of famous animals (alive and died), of animals that were castrated for practice of sports (especially equine) and finally of animals with demand of larger gametas than the production. In Brazil, approximately 48 animals of the races Nelore, Dutchwoman, Simental and Junqueira, as well as some mestizos were produced by TNCS and they are alive. Those clones are originating from of 11 animals (more than a copy for animal clonado) and there are still others you render to be born. Among the national clones, the oldest animal has approximately 4,5 years of age. Those data show, on one side the competence of the research and of the national technology, and for other, a small contribution for the genetic earnings and improvement of our flock. Finally, the application of the clonagem is now restricted to elite flocks and to you encourage with special characteristics. In no way the technique could be applied in commercial flocks, except for if important modifications in the process improved the efficiency of the technique.

Being like this, for the animal production, the clonagem of reproducers is, now, your only application commercially viable. In spite of this an animal clonagem in wide scale begins to be thought based on automation perspectives and evolution of the techniques of animal clonagem. Conclusions and perspectives As mentioned, the application of the final clonagem in the animal production is a great opportunity for the future, however, until the moment only few reproducers were clonados. The animals clonados, although they have contributed a little to the genetic improvement, they favored the study of alterations in the gestations and in the development, including aspects of the genetics citoplasmatica, epigen�ca, placenta�, obstetrics, and in the neonatologia of clones. It is waited that a contribution to the animal production happens when the final clonagem in wide scale if it turns possible. In the future, the clonagem will be certainly accompanied of the production of animals transgenicos, and proteins recombinantes (lactoferrina, factor IX, for instance) they will be produced in the milk of those animals, contributing to increase the production and to reduce the cost when compared the other methods of produ�/purifica� of proteins. The individuals' modification will also be able to allow the production of animals for xenotransplantes. Being like this, in the future, the biotecnologias of the reproduction and of the DNA recombinante as the artificial insemination (it WENT), embryo transfer (YOU), FIV, TNCS, transgenese, besides the improvement attended by markers, they will be used together for production, selection and multiplication of more productive animals. The selected animals will be multiplied by final clonagem, modified or not for recombinacion, and after appraised, distributed to the producers. The last ones can produce animals in system of defined handling, to the likeness of other creations with homogeneous genetic lineages, and to sell your products for specialized companies of food or of the pharmaceutical chain. Gratefulness To FAPESP for the financial aid, and CASTRATE her and to CNPq for the aid received for the grant holders maintenance.