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- Genetic structure, relationships and admixture with wild relatives in native pig breeds from Iberia and its islandsPublication . Gama, Luis; Martinez, Amparo; Carolino, Inês; Landi, Vincenzo; Delgado, Juan; Vicente, António; Sousa, ConceiçãoBackground: Native pig breeds in the Iberian Peninsula are broadly classified as belonging to either the Celtic or the Mediterranean breed groups, but there are other local populations that do not fit into any of these groups. Most of the native pig breeds in Iberia are in danger of extinction, and the assessment of their genetic diversity and population structure, relationships and possible admixture between breeds, and the appraisal of conservation alternatives are crucial to adopt appropriate management strategies. Methods: A panel of 24 microsatellite markers was used to genotype 844 animals representing the 17 most important native swine breeds and wild populations existing in Portugal and Spain and various statistical tools were applied to analyze the results. Results: Genetic diversity was high in the breeds studied, with an overall mean of 13.6 alleles per locus and an average expected heterozygosity of 0.80. Signs of genetic bottlenecks were observed in breeds with a small census size, and population substructure was present in some of the breeds with larger census sizes. Variability among breeds accounted for about 20% of the total genetic diversity, and was explained mostly by differences among the Celtic, Mediterranean and Basque breed groups, rather than by differences between domestic and wild pigs. Breeds clustered closely according to group, and proximity was detected between wild pigs and the Mediterranean cluster of breeds. Most breeds had their own structure and identity, with very little evidence of admixture, except for the Retinto and Entrepelado varieties of the Mediterranean group, which are very similar. Genetic influence of the identified breed clusters extends beyond the specific geographical areas across borders throughout the Iberian Peninsula, with a very sharp transition from one breed group to another. Analysis of conservation priorities confirms that the ranking of a breed for conservation depends on the emphasis placed on its contribution to the betweenand within-breed components of genetic diversity. Conclusions: Native pig breeds in Iberia reveal high levels of genetic diversity, a solid breed structure and a clear organization in well-defined clusters.
- O porco Malhado de Alcobaça : importância da sua conservação e divulgaçãoPublication . Vicente, António
- Malhado de Alcobaça: uma raça suína autóctone em risco de extinçãoPublication . Carolino, I.; Pereira, R. L. N.; Carolino, Nuno; Vicente, António
- Programa de melhoramento genético do porco Malhado de Alcobaça : avaliação genética para características produtivas e reprodutivasPublication . Vicente, António; Carolino, Nuno
- O teste de DNA como diagnóstico precoce de carnes PSE em suínosPublication . Carolino, I.; Vicente, António; Sousa, C. O.; Silva, F. S.; Carolino, Nuno
- Influência da dupla ninhada nos parâmetros produtivos e comportamentais em genética DanbredPublication . Caçador, J.; Vicente, António; Conceição, C.; Carolino, NunoThe pressure that the swine sector has been suffering searching for methods and techniques that are more efficient, capable of increasing the number of piglets per sow, led to the hiperprolific sows, which go against the conventional concepts of swine facilities concerning farrowing crates. Also, the animal welfare when it comes to farrowing crates starts to become a very discussed subject, as much for the piglets as for the sows. After several studies developed in various locations, which evidenced the benefits of farrowing crates with mixed litters, it was decided to study that kind of litter. Thereby it was tested if the productive values of hiperprolific sows would increase, and also if it would increase the welfare of the piglets. The study was conducted between 11th of April and 19th of July in Santo Cristo’s farm, which is exploited by Euroeste, SA. company, located in Cartaxo, Portugal. The aim of this study was to evaluate if mixed litters help to wean more piglets, if they gain more weight by having more food options, and if their welfare is improved, helping the animal to be better prepared for the future, after weaning. Initially, through analysis with SAS software, which included the fixed effects of type of method used (if mixed litter or control), the location in the farm where they were, the month of birth, the age at weaning and the cycle of the sow, we evaluated the number of piglets weaned per sow, the average weight per weaned piglet, the daily weight gain calculated with the total values of the weights, the daily weight gained calculated with the average values of the piglets, and the percentage of weaned animals in comparison to the initial number of litters. Secondly, through the SAS program, were analysed the individual weights registered at weaning of 857 piglets, with an average weight of 5,91±1,41kg, with the aim of evaluating the environmental factors such as the method, location in the farm, month of weaning, age at weaning, cycle of the sow and age of the piglets at the beginning of the study. In conclusion for the production parameters this method does not show significant improvements however, it also has no disadvantage in productive terms, which demonstrates that it is a viable alternative to the intensive systems of isolated farrowing systems implemented today in most of the intensive farms. Secondly, it can also be concluded that, in behavioural terms, this method showed some improvement in pre-weaning behaviour, by improving the interactions between litters, and the natural contact between the animals and the increase of consumption of pre-starter.
- Aplicações da rastreabilidade genética na fileira de produção suínaPublication . Carolino, M. I.; Vicente, António; Gama, Luis
- Parâmetros genéticos e efeitos ambientais de caracteres reprodutivos em suínos Malhado AlcobaçaPublication . Vicente, António; Carolino, Nuno; Pereira, Lisbete; Gama, LuisNo âmbito de um estudo sobre a população suína Malhado de Alcobaça, foram estimados os parâmetros genéticos e os efeitos ambientais para a prolificidade e número de leitões desmamados.Recolheram-se registos produtivos e genealógicos ao longo de 18 anos na única exploração (Selecpor, SA), com reprodutores desta raça, cujo efectivo adulto ronda as 170 fêmeas e 11 machos, obtendo-se 2658 registos de partos e 2569 registos de desmame de cerca de 530 fêmeas, a que correspondia uma matriz de parentesco com 819 indivíduos. As estimativas de parâmetros genéticos e efeitos fixos para a prolificidade (PROL) e número de leitões desmamados (NDL) foram obtidas por máxima verosimilhança restrita, através do BLUP – Modelo Animal, numa análise bivariada, com modelo de registos repetidos que incluía como efeitos aleatórios o valor genético e o efeito ambiental permanente da porca e como efeitos fixos o ano e mês de parto, o efeito linear da consanguinidade individual e os efeitos linear e quadrático da idade ao parto, utilizando-se o programa MTDFREML. Registou-se uma prolificidade média de 9,6 leitões nascidos totais por parto e 8,3 leitões desmamados por ninhada. Verificou-se uma depressão consanguínea de -0,0289 leitões na PROL e de -0,0200 leitões no NDL por cada aumento de 1% no coeficiente de consanguinidade dos reprodutores e que a idade ao parto apresenta um efeito quadrático em ambos caracteres, com valores próximos dos 3 anos. A heritabilidade estimada foi de 0, 05±0,026 para a PROL e 0,10±0,035 para o NDL, enquanto que o efeito ambiental permanente para os mesmos caracteres foi de, respectivamente, 0,08±0,025 e 0,04±0,027.
- Teste de performance em estação: raça suína Malhado de Alcobaça 2017Publication . Moreira, O.; Sequeira, A.; Vicente, António; Almeida, J.
- Managing the herdbook of an endangered Portuguese swine population: the Malhado de Alcobaça pigPublication . Vicente, António; Roque, A.; Bastos, J.; Carolino, NunoMalhado de Alcobaça breed is the 3rd Portuguese native swine breed and represents a population from the centre west of Portugal and was officially recognised in 2003. The herdbook has information of more than 11,000 animals (1985-2020) and the last animals have more than 10 known generations on their pedigree. It´s a very endangered breed with only 211 breeding sows, 12 boars and 9 active breeders. Since 2014 all candidates for breeding must be submitted to a grading process by analysing their morphology under 5 marks and, at the same time, placing an ear tag ID, collecting, simultaneously, tissue for DNA analysis, for parentage testing and genetic characterisation. All data from the gradings was analysed to obtain the descriptive statistics and the linear and quadratic effect of age at grading, besides considering the effects of breeder, gender and year. Since 2014, 448 pigs where graded (415 sows and 33 boars) with average age of 15.87±8.88 months (15.96±8.99♀; 14.61±7.35♂). Only 7 different breeders produced breeding sows and boars, and 4 of them are responsible for 83% of the breeding stock in use. For the grading grid (scale with maximum of 10 pts.) the average scores for morphology were 8.54±0.72 pts for type and development; 8.35±0.68 pts for back, loin and croup; 8.24±0.64 pts for shoulders, chest, belly and flanks; 7.99±0.81 pts for legs, stances and gaits; and 8.43±0.66 pts for sexual characteristics, genitals and nipples, obtaining and overall sum of 82.58±4.45 pts. Globally boars obtain more 1.5 points than sows and the score for legs was the lowest with higher coefficient of variation. Breeder and year of grading were significant (P<0.05) for all morphological traits analysed and gender was only significant (P<0.001) for back, loin and croup. Age at grading had a significant linear effect (P<0.05) in Overall sum and for some partial morphological scores