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RESUMO O presente trabalho é em relação às abelhas nativas sociais e como a ação humana interfere na existência desses insetos. Buscando responder como a atitude humana tem colaborado no declínio das abelhas nativas sem ferrão e quais atitudes podem ser tomadas para que isso diminua. Este tipo de estudo é importante para mostrar a importância das abelhas nativas sociais para a sociedade e a natureza, e também para incentivar atitudes que colaborem com a preservação. O objetivo central é analisar as ações humanas e suas consequências para as abelhas nativas. Os objetivos específicos são: Explicar algumas generalidades desses insetos que são subdivididos em diversas espécies; analisar a ação humana como agente causador da diminuição dessas abelhas; mostrar algumas atitudes que colaboram para a preservação delas. A hipótese da pesquisa é: as atitudes humanas antiecológicas são os principais fatores para o declínio das espécies nativas de abelhas. A pesquisa foi totalmente bibliográfica por meio de revisões de artigos científicos, livros e manuais que tratam sobre a criação desses insetos. Os principais resultados colhidos foram no geral confirmando a hipótese ações diretas como queimadas e desmatamento acentuam o declínio desses animais e podem levá-los a extinção, o que causaria vários impactos como a eliminação de vegetais que precisam da polinização das abelhas nativas, porém, com a conscientização e a valorização da atividade de criar esses insetos de uma maneira economicamente viável colabora para a conservação e o aumento das espécies na natureza. Palavras-chave: Abelhas sem ferrão. Meliponicultura. Preservação das abelhas sem ferrão.

Age at first calving (AFC) is characterized as a censored trait due to missing values provided by recording mistakes and nonoccur-rence or delay in calving communication. In this context, we aimed to compare several statistical methods for genetic evaluation of AFC in Guzerá beef cattle under a Bayesian approach. Seven different methods were used for this purpose. The traditional linear mixed model (LM), which considers only uncensored records; the LM with simulated records (SM), which is based on data augmentation framework; the penalty method, in which a constant of 21 d was added to censored records; the bivariate threshold-linear method considering (TLcens) or not (TLmiss) censored information; and the piecewise Weibull proportional hazards model considering (PWPHcens) or not (PWPH) censored records. Heritability estimates ranged from 0.19 (TLcens) to 0.28 (SM) in non-survival approaches; and 0.40 and 0.46 to PWPH and PWPHcens methods, respectively. In general, breeding values correlations between different methods and the percentage of selected bulls in common indicated reranking, with these correlation ranging from -0.28 (between SM and PWPH) to 0.99 (between TLmiss and LM). The traditional LM, which considers only uncensored records, should be preferred due to its robustness and simplicity. Based on cross-validation analyses, we conclude that the TLmiss could be also a suitable alternative for breeding value prediction, and censored methods did not improve the analysis.

A major objective of pork producers is to reduce production cost. Feeding may account for over 75% of pork production costs. Thus, selecting pigs for feed efficiency (FE) traits is a priority in pig breeding programs. While in the Americas, pigs are typically fed high-input diets, based on corn and soybean meal (CS); in Western Europe, pigs are commonly fed diets based on wheat and barley with high amounts of added protein-rich coproducts (WB), e.g., from milling and seed-oil industries. These two feeding scenarios provided a realistic setting for investigating a specific type of genotype by environment interaction; thus, we investigated the genotype by feed interaction (GxF). In the presence of a GxF, different feed compositions should be considered when selecting for FE. This study aimed to 1) verify the presence of a GxF for FE and growth performance traits in different growth phases (starter, grower, and finisher) of 3-way crossbred growing-finishing pigs fed either a CS (547 boars and 558 gilts) or WB (567 boars and 558 gilts) diet; and 2) to assess and compare the expected responses to direct selection under the 2 diets and the expected correlated responses for one diet to indirect selection under the other diet. We found that GxF did not interfere in the ranking of genotypes under both diets for growth, protein deposition, feed intake, energy intake, or feed conversion rate. Therefore, for these traits, we recommend changing the diet of growing-finishing pigs from high-input feed (i.e., CS) to feed with less valuable ingredients, as WB, to reduce production costs and the environmental impact, regardless of which diet is used in selection. We found that GxF interfered in the ranking of genotypes and caused heterogeneity of genetic variance under both diets for lipid deposition (LD), residual energy intake (REI), and residual feed intake (RFI). Thus, selecting pigs under a diet different from the diet used for growing-finishing performance could compromise the LD in all growth phases, compromise the REI and RFI during the starter phase, and severely compromise the REI during the grower phase. In particular, when pigs are required to consume a WB diet for growing-finishing performance, pigs should be selected for FE under the same diet. Breeding pigs for FE under lower-input diets should be considered, because FE traits will become more important and lower-input diets will become more widespread in the near future.

The objective of the present research was to identify the effect of rural extension on the productive performance of Brazilian agricultural establishments, using as a measure of performance the technical efficiency of farms. The data used refers to the microdata of the 2006 Agricultural Census, accessed directly from the IBGE secrecy room. For this, an approach that combines the stochastic production frontier structure, taking into account the selection bias in the adoption of the rural extension (Heckman's approach), with the entropy balancing method was used. The results show that the rural extension contributes, in fact, to increase the efficiency in the use of the productive factors, with the producers adopting, more technically efficient than the non-adopters. When considering the differences according to the size of the establishment, an even greater effect was observed for the group of large producers. In addition, in general, public rural extension generated higher technical efficiency scores than those obtained by establishments attended by the private service. Acknowledgement

6 pags., 5 figs., 1 tab., We report on experimental total electron scattering cross-section (TCS) from pyridine (CHN) for incident electron energies between 10 and 1000 eV, with experimental uncertainties within 5–10%, as measured with a double electrostatic analyser apparatus. The experimental results are compared with our theoretical calculations performed within the independent atom model complemented with a screening corrected additivity rule (IAM-SCAR) procedure which has been updated by including interference effects. A good level of agreement is found between both data sources within the experimental uncertainties. The present TCS results for electron impact energy under study contribute, together with other scattering data available in the literature, to achieve a consistent set of cross section data for modelling purposes., We acknowledge the financial support received from theSpanish Ministerio de Economia y Competitividad (Project FIS2016-80440), the European Union Seventh Frame-workProgramme (PEOPLE-2013-ITN-ARGENT Marie Curie project)under grant agreement no. 608163 and the European Union COSTAction CM1301 (CELINA). FFS acknowledges the Portuguese National Funding Agency FCT-MCTES through researcher positionIF-FCT IF/00380/2014 and together with PLV the research grantUID/FIS/00068/2013. This work was also supported by RadiationBiology and Biophysics Doctoral Training Programme (RaBBiT,PD/00193/2010); UID/Multi/ 04378/2013 (UCIBIO)

Genome association analyses have been successful in identifying quantitative trait loci (QTLs) for pig body weights measured at a single age. However, when considering the whole weight trajectories over time in the context of genome association analyses, it is important to look at the markers that affect growth curve parameters. The easiest way to consider them is via the two-step method, in which the growth curve parameters and marker effects are estimated separately, thereby resulting in a reduction of the statistical power and the precision of estimates. One efficient solution is to adopt nonlinear mixed models (NMM), which enables a joint modeling of the individual growth curves and marker effects. Our aim was to propose a genome association analysis for growth curves in pigs based on NMM as well as to compare it with the traditional two-step method. In addition, we also aimed to identify the nearest candidate genes related to significant SNP (single nucleotide polymorphism) markers. The NMM presented a higher number of significant SNPs for adult weight (A) and maturity rate (K), and provided a direct way to test SNP significance simultaneously for both the A and K parameters. Furthermore, all significant SNPs from the two-step method were also reported in the NMM analysis. The ontology of the three candidate genes (SH3BGRL2, MAPK14, and MYL9) derived from significant SNPs (simultaneously affecting A and K) allows us to make inferences with regards to their contribution to the pig growth process in the population studied.