The demand for special breeding programmes for organic pig meat production is based on the assumption that pigs kept under organic conditions need different biological properties compared with conventionally kept pigs in order to achieve a good performance. This would mean that genotype-environment interactions exist. Therefore, 682 pigs of seven different genotypes were tested for growth performance and carcass quality under conventional and organic environments at two testing stations to verify genotype-environment interactions. All genotypes achieved significantly better results within the conventional environment and there were significant interactions between genotype and environment for all the criteria of growth performance and carcass quality. The interactions are mainly caused by varying differences between organic and conventional systems within genotypes, but for all traits, except weight gain, no major shift of the ranking order within environment between genotypes. Although statistically significant genotype-environment interactions exist, the modern genotypes selected under conventional conditions are also superior to indigenous breeds under organic conditions in economically important traits. Hence, it can be concluded from these results that no special breeding programme is necessary for organic production systems.

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The study aimed to test a very early immunization of pigs to prevent boar taint with regard to its practicability and influence on production performance, its reliability in ensuring good meat and fat quality, and animal welfare. Immunization was already conducted at piglet production stage and could be easily integrated into routine vaccination (week 3) and weaning practices (week 7). The fattening and slaughter performance of the animals was not affected by the immunization regime and was within the usual range. In addition, there were no abnormalities in animal behavior and the prevalence of injuries caused by aggressive interactions. All animals were classified as infertile on the basis of the histological examination of the testicles. However, the testosterone levels measured at slaughter were significantly higher in animals of the early immunization regime than in animals subjected to the standard immunization regime. Androstenone and skatole levels as the main components of boar taint were, on average, higher and varied to a greater extent in early immunized animals. Furthermore, the comparison of the immunization scheme did not result in significant differences for meat quality and for fatty acid composition.

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The herbaceous vine Mandevilla funiformis (Vell.) K. Schum. occurs in open vegetation in the Southern Brazil. The present study was carried out in a sandbank, east of Florianópolis, Santa Catarina State. Floral morphology, nectar features (production pattern, removal effects, and standing crop), floral visitors (including pollinator, robber and thief of nectar), fruit set and seed germination of M. funiformis were studied. Every plant produced an average of 31.5 inflorescences. The average total volume and the average sugar concentration of nectar were 81 μL and 24%, respectively. The bees Epicharis (Anepicharis) dejeanii, Eufriesea violacea, Bombus (Fervidobombus) morio, the hummingbird Amazilia fimbriata, and two species of Hesperiidae were considered potential pollinators. The other species were considered consumers, nectar robbers or nectar thieves. Fruit set was 35.6% and average percentage of seed germination was 68%, indicating that visitors are efficient pollinators. This study was the first to report production and consumption of nectar in different floral stages (pre-anthesis, flower open, and after corolla abscission). The high and continuous production of nectar by M. funiformis, from floral buds in the pre-anthesis until after the corolla abscission show a real food availability in different ways (pollinators, consumers, robbers or thieves of nectar).