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- On the origins of American Criollo pigs: A common genetic background with a lasting Iberian signaturePublication . Revidatti, M. A.; Gama, L.L.T.; Martin Burriel, I.; Cortés Gardyn, O.; Cappello Villada, J. S.; Carolino, Inês; Javier Cañón, F.; Ginja, C.; Sponenberg, P.; Vicente, António; Zaragoza, P.; Vicente Delgado, J.; Martinez, A.American Criollo pigs are thought to descend mainly from those imported from the Iberian Peninsula starting in the late 15th century. Criollo pigs subsequently expanded throughout the Americas, adapting to very diverse environments, and possibly receiving influences from other origins. With the intensification of agriculture in the mid-20th century, cosmopolitan breeds largely replaced Criollo pigs, and the few remaining are mostly maintained by rural communities in marginal areas where they still play an important socio-economic and cultural role. In this study, we used 24 microsatellite markers in samples from 1715 pigs representing 46 breeds with worldwide distribution, including 17 American Criollo breeds, with the major focus of investigating their genetic diversity, structure and breed relationships. We also included representatives of the Iberian, Local British, Hungarian, Chinese and Commercial breeds, as well as Wild Boar, in order to investigate their possible influence in the genetic composition of Criollos. Our results show that, when compared with the other breeds, Criollo pigs present higher levels of genetic diversity, both in terms of allelic diversity and expected heterozygosity. The various analyses indicate that breed differentiation overall explains nearly 21% of the total genetic diversity. Criollo breeds showed their own identity and shared a common genetic background, tending to cluster together in various analyses, even though they differ from each other. A close relationship of Criollos with Iberian breeds was revealed by all the different analyses, and the contribution of Iberian breeds, particularly of the Celtic breeds, is still present in various Criollo breeds. No influence of Chinese breeds was detected on Criollos, but a few were influenced by Commercial breeds or by wild pigs. Our results confirm the uniqueness of American Criollo pigs and the role that Iberian breeds have played in their development.
- Biodiversidade caprina em PortugalPublication . Carolino, Nuno; Sousa, C. B.; Carolino, I.; Santos-Silva, F.; Sousa, C. O.; Vicente, António; Ginja, C.; Gama, LuisEm Portugal a produção de caprinos está normalmente associada a zonas pobres e a recursos agrossilvopastoris dificilmente aproveitáveis por outras espécies. O efetivo caprino é atualmente constituído por cerca de 340 mil fêmeas reprodutoras, 1/8 das quais representadas pelas raças autóctones Algarvia, Bravia, Charnequeira, Preta de Montesinho, Serpentina e Serrana. A origem e evolução dos efetivos caprinos portugueses são controversas, mas diversos autores sugerem que resultam de cruzamentos entre animais provenientes de diversas regiões da Península Ibérica e do norte de África. As atuais seis raças autóctones apresentam um grau de diferenciação inter-racial reduzido, mas níveis elevados de diversidade genética. A maioria dos caprinos é explorada em sistemas extensivos, em equilíbrio com o meio ambiente, na dupla vertente carne-leite, em que o leite produzido é utilizado no fabrico de queijo. Devido à diversidade de raças caprinas e de sistemas de produção, bastante associados a tradições e às características edafoclimáticas de cada região, existe uma grande variedade de produtos transformados (queijos e carne), alguns deles com certificações reconhecidas pela União Europeia (Denominação de Origem Protegida, Indicação Geográfica Protegida e Especialidade Tradicional Garantida). Presentemente, todas as raças caprinas autóctones dispõem de programas de conservação e melhoramento, da responsabilidade das Associações de Criadores gestoras dos livros genealógicos, com o apoio de várias instituições e a supervisão do Ministério da Agricultura. Contribuindo para o sustento de inúmeras empresas agrícolas familiares portuguesas, os caprinos são fundamentais para a fixação de populações no espaço rural e para a sua gestão sustentável. Não sendo um sector em expansão, a caprinicultura portuguesa, continua a desempenhar um papel extremamente importante do ponto de vista socioeconómico e cultural nas regiões mais desfavorecidas do interior do país.
- Genetic diversity in native and commercial breeds of pigs in Portugal assessed by microsatellitesPublication . Vicente, António; Carolino, M. I.; Sousa, M. C.; Ginja, C.; Silva, F. S.; Martinez, A. M.; Vega-Pla, J. L.; Carolino, Nuno; Gama, LuisPopulation structure and genetic diversity in the Portuguese native breeds of pigs Alentejano (AL), Bísaro (BI), and Malhado de Alcobaça (MA) and the exotic breeds Duroc (DU), Landrace (LR), Large White (LW), and Pietrain were analyzed by typing 22 microsatellite markers in 249 individuals. In general, the markers used were greatly polymorphic, with mean total and effective number of alleles per locus of 10.68 and 4.33, respectively, and an expected heterozygosity of 0.667 across loci. The effective number of alleles per locus and expected heterozygosity were greatest in BI, LR, and AL, and least in DU. Private alleles were found in 9 of the 22 markers analyzed, mostly in AL, but also in the other breeds, with the exception of LW. The proportion of loci not in Hardy-Weinberg equilibrium in each breed analyzed ranged between 0.23 (AL) and 0.41 (BI, LW, and Pietrain), mostly because of a less than expected number of heterozygotes in those loci. With the exception of MA, all breeds showed a significant deficit in heterozygosity (F(IS); P < 0.05), which was more pronounced in BI (F(IS) = 0.175) and AL (F(IS) = 0.139), suggesting that inbreeding is a major concern, especially in these breeds that have gone through a genetic bottleneck in the recent past. The analysis of relationships among breeds, assessed by different methods, indicates that DU and AL are the more distanced breeds relative to the others, with the closest relationship being observed between LR and MA. The degree of differentiation between subpopulations (F(ST)) indicates that 0.184 of the total genetic variability can be attributed to differences among breeds. The analysis of individual distances based on allele sharing indicates that animals of the same breed generally cluster together, but subdivision is observed in the BI and LR breeds. Furthermore, the analysis of population structure indicates there is very little admixture among breeds, with each one being identified with a single ancestral population. The results of this study confirm that native breeds of pigs represent a very interesting reservoir of allelic diversity, even though the current levels of inbreeding raise concerns. Therefore, appropriate conservation efforts should be undertaken, such as adopting strategies aimed at minimizing inbreeding, to avoid further losses of genetic diversity.