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• Bibliographic mapping was used to identify major research groups and trends for heat tolerance in farm animals. • Major research countries are the USA, China, Brazil, India, Australia and UK with 54% of all publications. • There was a gradual drift in heat stress studies from animal physiology towards genomics and cellular biology. • This area of research is growing 3x faster than publication rates in general. • Most papers are on cattle, indicating the need for studies with other species. This study looks at the bibliographic mapping of citation, co-occurrence of keywords, co-citation and bibliographic coupling for heat tolerance in farm animals. Data was obtained from Scopus (Elsevier) and analysed in Vosviewer. Several salient points emerge from our analysis. We found a total of 1728 documents from 102 countries, of which 54% are from six countries (USA, China, Brazil, India, Australia and UK). While heat tolerance is important, Global South countries have recently become more important in this topic. Nevertheless, researchers from this region appear relatively isolated using the metrics of this study. One potential factor contributing to isolation could be lack of funding. This is discussed in the light of current Article Processing Charges. We also note a gradual drift in heat stress studies from animal physiology towards genomics and cellular biology. The paper can help understanding tendencies in this field of research and may point to future actions within the research community. This paper also shows the need to strengthen studies in less favoured areas and with species such as small ruminants, whereby small holders may be harder hit by climate change. Biases in the analysis could arise due to low citations from recent papers or those not indexed in Scopus. [Display omitted] [ABSTRACT FROM AUTHOR]

• In the Brazilian pork supply chain, horizontal relationships positively influence performance of Brazilian pig-farmers. • In the Brazilian pork supply chain, horizontal relationships positively influence farmer-buyer vertical relationships. • Vertical relationships positively influence performance of Brazilian pig farmers. • Farmer-buyer relationship quality positively influences performance of Brazilian pig farmers. According to the literature, vertical and horizontal relationships are of key importance to farmer performance. However, most studies have examined these relationships using distinct models. This paper contributes with new insights to the supply chain management and network theories by using a single model to analyse how horizontal relationships impact on vertical relationships and how these jointly affect the performance of Brazilian pig farmers. Data were obtained from 269 farmers delivering pigs through contracts and spot markets in southern Brazil. The results demonstrate that both vertical and horizontal relationships can improve farmer performance. Moreover, horizontal relationships positively influence vertical relationships by improving the exchange of information between farmers and buyers. Furthermore, the findings suggest that these relationships are sensitive to the context (spot market or contracted production) in which the transactions are executed. The study draws relevant management implications for pig farmers, buyers and farmer associations. [ABSTRACT FROM AUTHOR]

• This paper set out to evaluate to what extent efficiency in production and the position of dairy farmers in the social network, formed by the Program for the Development of Dairy Farming (PDPL), affect the diffusion of technical information and technologies in the production chain. • The efficiency analysis revealed benefits when inefficient dairy farmers sought best practices and the optimal production scale; • Through the model created, it was found that the selection of technically efficient dairy farmers for the diffusion process is a good policy, but when the adoption pay-off is low and resources are scarce, selecting central farmers would be the more appropriate policy. • It was evidenced that the choice of the initial adopters, adoption and non-adoption pay-off values, and the relationship pattern all influence the diffusion process. Farmers' poor levels of knowledge are related to low rates of efficiency and productivity in milk production in Brazil due to problems of information diffusion and innovation. This paper set out to evaluate to what extent efficiency in production and the position of dairy farmers in the social network, formed by the Program for the Development of Dairy Farming (PDPL), affect the diffusion of technical information and technologies in the production chain. The data used in the study were made available by the PDPL technical staff and refer to 31 dairy farmers, located in municipalities in the Zona da Mata micro region of the state of Minas Gerais, who participated in the Program in 2016. Through Social Network Analysis, Data Envelopment Analysis and Agent-Based Modeling, a diffusion model was structured into which information on the technical efficiency of the dairy farmers was incorporated, as well as information about their relationship pattern. The efficiency analysis showed benefits when inefficient farmers sought best practices and the optimal production scale. Through the model created, it was found that the selection of technically efficient dairy farmers for the diffusion process is a good policy, but when the adoption pay-off is low and resources are scarce, selecting central farmers would be the more appropriate policy. Additionally, it was shown that the choice of the initial adopters, adoption and non-adoption pay-off values, and the relationship pattern all influence the diffusion process. The study, thus, suggests a new way of choosing policies to accelerate the diffusion of information and technology in typical dairy systems in Brazil and other countries. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this paper is to model variations in test-day milk yields of first lactations of Holstein cows by RR using B-spline functions and Bayesian inference in order to fit adequate and parsimonious models for the estimation of genetic parameters. They used 152,145 test day milk yield records from 7317 first lactations of Holstein cows. The model established in this study was additive, permanent environmental and residual random effects. In addition, contemporary group and linear and quadratic effects of the age of cow at calving were included as fixed effects. Authors modeled the average lactation curve of the population with a fourth-order orthogonal Legendre polynomial. They concluded that a cubic B-spline with seven random regression coefficients for both the additive genetic and permanent environment effects was to be the best according to residual mean square and residual variance estimates. Moreover they urged a lower order model (quadratic B-spline with seven random regression coefficients for both random effects) could be adopted because it yielded practically the same genetic parameter estimates with parsimony. [Copyright &y& Elsevier]

Abstract: Brazil has various species of domestic animals, which developed from breeds brought by the Portuguese settlers soon after the discovery of the country. After being submitted to a long process of natural selection, these breeds present characteristics adapted to specific Brazilian environmental conditions, and are known as “criollo”, “local” or naturalized breeds. From the beginning of the 20th century, some exotic breeds, selected in temperate regions, have begun to be imported, and, although more productive, they do not have adaptive traits, such as resistance to disease and parasites found in the naturalized breeds. Even so, they gradually replaced the native breeds, to such an extent that the latter are in danger of extinction. To avoid further loss of this important genetic material, in 1983 the National Research Center for Genetic Resources and Biotechnology (Cenargen) of the Brazilian Agricultural Research Corporation (Embrapa) decided to include conservation of animal genetic resources among its priorities. The conservation activities have been conducted under the Brazilian Genetic Resources Network — Renargen, and is carried out by various research centres of Embrapa, universities and State research institutions, as well as by private farmers, with a single coordinator at national level, Cenargen. The in situ conservation of cattle, horses, buffaloes, donkeys, goats, sheep and pigs is being carried out by Conservation Nuclei, located in the animal''s original habitat. Ex situ conservation is centred at the Brazilian Animal Germplasm Bank (AGB), kept at Cenargen. This is responsible for the storage of semen and embryos of various breeds of domestic animals threatened with extinction. Presently the AGB has almost 60,000 doses of semen and more than 250 embryos, as well as over 7000 DNA samples. An important challenge for this program is to increase awareness within the different segments of society in terms of the importance of the conservation of animal genetic resources. The development and evolution of Renargen and its efforts to facilitate the conservation of genetic resources of livestock in Brazil are described in this paper. [Copyright &y& Elsevier]

Abstract: How to improve access to land and livestock production in synergy with ecosystem conservation? The paradigm occurring in natural grasslands of the Southern Brazilian Campos biome is used to illustrate the dilemma. This paper aims to contribute by addressing the technical bases being used by legislations concerning access to land and incentive to production and their consequences for natural grassland systems. Current policies have a production-oriented focus trying to promote livestock productivity by setting minimum stocking rates to be applied in grasslands. The unexpected results are overgrazing and reduction of natural grasslands, so the dilemma production versus conservation emerges. There is a need for adapting access to land legislations to the new environmental functions expected for natural grasslands, which warrant a conservation-oriented approach according to their multifunctional role. Integrated measures are proposed, which could be helpful in resolving the conflicting compromises regarding the inducement of production and the promotion of natural resources conservation. [Copyright &y& Elsevier]

Abstract: This paper deals with the effects of hair coat characteristics on the sweating rate of Brazilian Braford cows and estimation of heritabilities and genetic correlations of these traits. Data (n =1607) on hair length, coat thickness, hair diameter, number of hairs per unit area, coat reflectance and sweating rate were recorded from heifers and cows of a commercial herd managed on range under extensive system. The data were analyzed considering the following effects on the model for hair coat traits: classes of sires and contemporary groups; linear effects of month and genotype; linear and quadratic effects of age. The effect of sire was important (P <0.05) for all hair coat traits, except for number of hairs; contemporary groups affected (P <0.05) all hair coat traits; the effect of sampling month was important (P <0.05) for hair length and reflectance; genotype affected (P <0.05) hair length, diameter and coat reflectance; the quadratic effect of age was important (P <0.05) only for coat reflectance. Two models were used to analyze the sweating rate. The first model considered the following fixed effects: classes of contemporary groups and sires; linear effect of genotype, coat thickness, hair length, hair diameter, number of hairs, coat reflectance; linear and quadratic effects of time of day, age, air temperature, partial vapour pressure and radiant heat load. The second model used for the sweating rate considered the same fixed effects for the first model, except that the hair coat characteristics were adjusted for important effects used in the models to analyze hair coat traits. All meteorological factors and contemporary groups were important (P <0.05) on variation of sweating rate in both models. The Restricted Maximum Likelihood (REML) method was used to estimate variance and covariance components under the sire model. Results included heritability estimates in narrow (h 2 ) and broad (H 2) sense for single-trait analyzes: hair thickness (h 2 =0.16; H 2 =0.26); hair length (h 2 =0.18; H 2 =0.39); number of hairs (h 2 =0.08±0.07; H 2 =0.08±0.07); hair diameter (h 2 =0.12±0.07; H 2 =0.12±0.07); coat reflectance (h 2 =0.30; H 2 =0.42); and sweating rate (h 2 =0.10±0.07; H 2 =0.10±0.07). In general, the genetic correlations between the adaptive traits were favorable as for the direction to select for adaptation in tropical environment; however, they presented high standard errors. The results of this study imply that hair coat characteristics and sweating ability are important for the adaptability to heat stress and they must be better studied and further considered for selection for genetic progress of adaptation in tropical environment. [Copyright &y& Elsevier]