Increasing Population Status of Broad-Snouted Caiman (Caiman latirostris) Based on Sustainable Use Strategies in a Managed Protected Area in Santa Fe, Argentina.

People and crocodilians have engaged in interactions since the earliest human settlements. After many years of escalating non-regulated use, coupled with emerging threats such as habitat modification, environmental pollution, and the exponential growth of human populations, natural crocodilian populations have been pushed to the brink of extinction. To prevent this, various initiatives have implemented strategies to prevent local extinction. Reinforcing wild populations through reintroductions and head-starting programs has been considered the safest approach to recovering crocodilian populations. Subsequently, the concept of sustainability emerged. In the case of many historically exploited crocodilian species, it became evident that rational utilization need not adversely affect population status; on the contrary, there were clear signs of recovery when local communities were involved. In 1990, the broad-snouted caiman (Caiman latirostris) was in a critical state due to decades of poaching and the aforementioned threats. In response, the "Monitoring and restocking program of the broad-snouted caiman for management purposes", commonly known as Proyecto Yacaré, was established to study population abundance and assess the biological, ecological, and social response to this management methodology. As a result of the eggs's harvest, a proportion equivalent to or greater than what would have survived in natural conditions was released into the original habitat where the eggs were collected. The surplus was allocated for leather and meat production with a focus on economic and environmentally sustainable practices, without affecting biodiversity or threats to the managed species. The in situ work carried out by this program has been crucial for the recovery of broad-snouted caiman populations under the "incentives for conservation" system, whereby local communities receive benefits for nest identification and egg harvesting. Over time, conservation incentives have become significant contributors to regional economies. This study illustrates how C. latirostris populations increased due to the implementation of egg harvesting by local communities in a natural reserve for management purposes. This population increase was detected through continuous night monitoring and an analysis of the number of nests in the area. Currently, C. latirostris populations have transitioned from being among the most threatened to becoming one of the most abundant throughout their distribution area. Based on the analyzed information, we may affirm that the commercial value of these species is one of the most relevant aspects contributing to the sustainability of these programs, primarily due to the change in perception generated among local communities. Therefore, identifying and controlling factors affecting these programs are fundamental for the conservation of these species.

The Livestock Frontier in the Paraguayan Chaco: A Local Agent-based Perspective.

Deforestation is one of the most relevant transformations characterizing global environmental change in the tropics at present. There is wide consensus in pointing the context-dependent nature of tropical deforestation. In this sense, a better characterization of the phenomenon considering the social context could provide a more accurate picture of tropical deforestation. With this aim, a Q-methodology discourse analysis was conducted to characterise the different discourses that coexist in the particular region of the Paraguayan Chaco concerning the development of cattle ranching and derived deforestation. Four different discourses were identified as making sense the wide range of interests and values coexisting and clashing in the Paraguayan Chaco, namely: the Environmentalist discourse, the Business discourse, the Resigned discourse, and the Possibilist discourse. The results point that the fundamental differences between the discourses are largely explained by the different positions on three specific domains: (i) the socio-economic benefits the expansion of cattle ranching brings about; (ii) the environmental impacts the expansion of cattle ranching and the derived deforestation brings on; and, finally (iii) the degree to which an active intervention from the side of policy making to regulate the expansion of cattle ranching and to minimize possible detrimental effects is seen as necessary. The position of the different discourses in relation to these domains could help policy makers to make measures and regulations more widely accepted and followed.

Amazon deforestation: A dangerous future indicated by patterns and trajectories in a hotspot of forest destruction in Brazil.

In recent years, the loss of forest in the Brazilian Amazon has taken on alarming proportions, with 2021 recording the largest increase in 13 years, particularly in the Abunã-Madeira Sustainable Development Reserve (SDR). This has significant environmental, social, and economic repercussions globally and for the local communities reliant on the forest. Analyzing deforestation patterns and trends aids in comprehending the dynamics of occupation and deforestation within a critical Amazon region, enabling the inference of potential occupation pathways. This understanding is crucial for identifying deforestation expansion zones and shaping public policies to curb deforestation. Decisions by the Brazilian government regarding landscape management will have profound environmental implications. We conducted an analysis of deforestation patterns and trends up to 2021 in the municipality (county) of Lábrea, located in the southern portion of Amazonas state. Deforestation processes in this area are likely to spread to the adjacent "Trans-Purus" region in western Amazonas, where Amazonia's largest block of remaining rainforest is at risk from planned highways. Annual deforestation polygons from 2008 to 2021 were categorized based on occupation typologies linked to various actors and processes defined for the region (e.g., diffuse, linear, fishbone, geometric, multidirectional, and consolidated). These patterns were represented through 10 × 10 km grid cells. The findings revealed that Lábrea's territory is predominantly characterized by the diffuse pattern (initial occupation stage), mainly concentrated in protected areas. Advanced occupation patterns (multidirectional and consolidated) were the primary contributors to deforestation during this period. Observed change trajectories included consolidation (30.8%) and expansion (19.6%) in the southern portion of the municipality, particularly along the Boi and Jequitibá secondary roads, providing access to large illegal landholdings. Additionally, non-change trajectories (67%) featured initial occupation patterns near rivers and in protected areas, likely linked to riverine and extractive communities. Tailoring measures to control deforestation based on actor types and considering stages of occupation is crucial. The techniques developed in this study provide a comprehensive approach for Amazonia and other tropical regions.

Extension services can promote pasture restoration: Evidence from Brazil's low carbon agriculture plan.

Innovation and improved practices in the livestock sector represent key opportunities tomeet global climate goals. This paper provides evidence that extension services can pro-mote pasture restoration in cattle ranching in Brazil. We use a randomized controlledtrial implemented in the context of the ABC Cerrado (a large-scale program launched in2014 aimed at fostering technology adoption through a combination of training andtechnical assistance) to examine the effects of different types of extension on agriculturalpractices, input use, and productivity. Providing technical assistance to previously trainedproducers promoted pasture restoration, induced farmers to use inputs more intensively,helped them to improve their management and soil conservation practices, and substan-tially increased revenues. A cost­benefit calculation indicates that US$1 invested in theABC Cerrado program increased profits by US$1.08 to $1.45. Incorporating carbonsavings amplifies this return considerably.

Effects of low-intensity cattle ranching on amphibians in the Ñeembucú Wetland Complex, Paraguay / Efectos de la ganadería de baja intensidad sobre los anfibios en el Complejo de Humedales Ñeembucú, Paraguay

Cattle in wetlands impact water quality through waste excretion, which deposits excess nutrients, as well as decreasing the biomass and height of vegetation through trampling and herbivory. Amphibians are sensitive to these changes due to their porous skin and reliance on vegetated microhabitats. Previous studies examining the effect of cattle on amphibians in wetlands report conflicting results, exemplifying the need to avoid overgeneralizations and instead examine specific environments. In the Ñeembucú Wetland Complex in Paraguay, low-intensity cattle ranching is a common practice. This study seeks to understand how the presence of cattle in these operations impacts water chemistry and amphibian species richness, as well as determining which cattle effects (eutrophication, nutrient loading, and decreased vegetation height diversity) have the greatest impact on amphibian communities. We anticipated that increased cattle presence would negatively impact wetland condition, and consequentially lower amphibian species richness. Data was collected over seven weeks at Estancia Santa Ana, a low-intensity cattle ranch in Pilar, Paraguay. Cattle presence was measured through cow footprints and feces densities, while a vegetation survey and water quality testing (nitrate, phosphate, and dissolved oxygen) served as environmental metrics. Pitfall trapping was used to gather information on amphibian species richness and community composition. A Pearson parametric correlation test and Factor Analysis of Mixed Data in R were then used to understand the relationship between variables. Very few statistically relationships were found between variables, and those that existed showed a very weak correlation. This suggests that cow presence does not have as strong of an impact on water quality or amphibian species richness as expected. Terrestrial and aquatic vegetation were found to explain much of the variation among the data, which verifies the importance of amphibians' microhabitats. While future research comparing generalist and specialist species in the area is necessary, these initial results suggest a hopeful future for collaboration on environmental efforts with low-intensity cattle ranchers.(AU)

Efectos de la ganadería de baja intensidad sobre los anfibios en el Complejo de Humedales Ñeembucú, Paraguay. La ganadería en los humedales afecta a la calidad del agua por excreción que añade nutrientes excesivos, además de reducir la altura y biomasa de vegetación a causa de pisar y comerla. Los anfibios son sensibles a estos cambios a causa de su piel porosa y su dependencia de la vegetación como hábitat. Estudios anteriores que investigaban los efectos del ganado en anfibios descubrieron resultados en conflicto, y así es importante evitar generalizar sobre todas las especies y ambientes. En los humedales de Ñeembucú en Paraguay, los ranchos con una densidad baja de vaca y un cambio mínimo al ambiente son muy comunes. Esta investigación trata de entender como la presencia del ganado en los ranchos afecta la calidad del agua y la riqueza de especies de anfibios, además de cuales factores (eutrofización, nutrientes excesivos o menos diversidad de vegetación) tienen el impacto más grande en los anfibios. Esperábamos que una presencia más alta de ganado causaría daño a la calidad del agua, y por eso, habría menos especies de anfibios presentes. Los datos se recogieron por siete semanas en Estancia Santa Ana, una estancia cerca a Pilar, Paraguay. La presencia de la ganadería se midió por la densidad de heces y huellas, y el medioambiente se analizó por un estudio de la vegetación y pruebas del agua (nitrato, fosfato y oxígeno). Se usan trampas pozos para capturar las ranas y coleccionar información sobre la riqueza de especies y la composición de la comunidad. Se usa la prueba de correlación paramétrica de Pearson y un Factor Analysis of Mixed Data en R para entender las relaciones entre las variables. Pocas relaciones de significado estadístico existen, y las que existen muestran una correlación muy débil. Eso sugiere que la ganadería no tenga un impacto muy grande en la calidad del agua o la riqueza de las especies como esperábamos. Vegetación terrestre y acuática explica la mayoría de la variación en los datos, y eso confirma la importancia de los hábitats de los anfibios. Los resultados sugieren un futuro optimista en cuanto a la colaboración entre los esfuerzos de conservación y los rancheros.(AU)

Choosing what is left: the spatial structure of a wild herbivore population within a livestock-dominated landscape.

Shrublands and grasslands comprise over 30% of the land surface and are among the most exploited ecosystems for livestock production. Across natural landscapes, the distribution and abundance of wild herbivores are affected by interspecific competition for foraging resources, hunting and the development of infrastructure among other factors. In Argentine Patagonia, the abundance of domestic sheep grazing on native vegetation outnumbers the widely distributed guanaco (Lama guanicoe) and sheep ranching monopolizes the most productive lands. In this work, we aimed to assess the spatial variation in the abundance of guanacos in Península Valdés, a representative landscape of Patagonia, investigating the incidence of natural and human-related factors. We conducted ground surveys during the austral autumn in 2017 totaling 383.4 km along areas with and without sheep ranching. We built density surface models to account for the variation in guanaco abundance and obtained a map of guanaco density at a resolution of 4 km2. We estimated an overall density of 11.71 guanacos.km-2 for a prediction area of 3,196 km2, although the density of guanacos tripled in areas where sheep ranching was terminated (in around 20% of the surface of Península Valdés) compared to areas with sheep. Guanacos were more abundant at lower values of primary productivity and sheep stocking rates and further from inhabited ranch buildings, suggesting competition with sheep and conflict with humans. Although guanacos selected open, grass-dominated habitats across sheep-free sites, fences dividing properties and paddocks played a significant role in the spatial structure of their population in Península Valdés affecting negatively the abundance of guanacos. Our results indicate that actions to improve habitat connectivity for guanacos, favor the coexistence among guanacos and sheep ranching, and promote responsible human activities and attitudes towards wildlife are needed.

Production behavior and prices of beef cattle in the Brazilian Amazon / Comportamento da produção e dos preços de bovinos de corte na Amazônia Brasileira

This study evaluates the production behavior and prices in the beef cattle industry in the Brazilian Amazon. We used time series data obtained from various sources and employed multiple regression and polynomial regression analysis. For the price analysis, we used the classical time series model and separated the seasonal and cyclic indices based on the 12-month centered moving average. The analyses covered the period from 1990 to 2015, when the regional cattle population grew at a rate of 5% per year, compared to the national growth rate of 1.7%. The price analysis reveals the existence of cycles in regional cattle ranching, defined mainly by an inverse correlation between the price of fattened cattle and the slaughter of matrices. As for the variables determining the growth of the cattle population, we find that rural credit policy assumes an important role in enabling the supply of resources for financing livestock projects that are more popular than investments in agriculture. The creation and structuring of state agricultural defense agencies in the late 1990s represents an important measure in the institutional sphere, as the implementation of animal health policies and programs has generated a favorable environment for the expansion of investments in meat production and processing, in addition to opening up opportunities for trade in the domestic and international markets.

O artigo avalia o comportamento da produção e dos preços no mercado da pecuária de corte da Amazônia brasileira. Utilizaram-se dados de séries temporais obtidos em diversas fontes e submetidos às análises de regressão múltipla e regressão polinomial. Para a análise de preços utilizou-se o modelo clássico de séries temporais com a separação dos índices sazonais e cíclicos com base na média móvel centrada em doze meses. As análises abrangem o período de 1990 a 2015, fase em que o rebanho bovino regional evoluiu a uma taxa de 5% ao ano, frente a um crescimento de 1,7% do rebanho nacional. A análise de preços revelou a existência de ciclos na pecuária bovina regional, definidos, principalmente, pela correlação inversa entre o preço do boi gordo e o abate de matrizes. Quanto às análises das variáveis determinantes do crescimento da produção, configurado na expansão do rebanho, constatou-se que a política de crédito rural assumiu papel importante ao viabilizar a oferta de recursos para o financiamento de projetos pecuários que ganharam espaço frente aos investimentos em agricultura. A criação e estruturação das agências estaduais de defesa agropecuária, a partir do final da década de 1990, representou avanço importante na esfera institucional, pois ao executarem as políticas e programas de sanidade animal tem gerado um ambiente favorável para a expansão dos investimentos na produção e processamento, além de abrir oportunidades para comercialização no mercado interno, nacional e internacional.

Production behavior and prices of beef cattle in the Brazilian Amazon / Comportamento da produção e dos preços de bovinos de corte na Amazônia Brasileira

This study evaluates the production behavior and prices in the beef cattle industry in the Brazilian Amazon. We used time series data obtained from various sources and employed multiple regression and polynomial regression analysis. For the price analysis, we used the classical time series model and separated the seasonal and cyclic indices based on the 12-month centered moving average. The analyses covered the period from 1990 to 2015, when the regional cattle population grew at a rate of 5% per year, compared to the national growth rate of 1.7%. The price analysis reveals the existence of cycles in regional cattle ranching, defined mainly by an inverse correlation between the price of fattened cattle and the slaughter of matrices. As for the variables determining the growth of the cattle population, we find that rural credit policy assumes an important role in enabling the supply of resources for financing livestock projects that are more popular than investments in agriculture. The creation and structuring of state agricultural defense agencies in the late 1990s represents an important measure in the institutional sphere, as the implementation of animal health policies and programs has generated a favorable environment for the expansion of investments in meat production and processing, in addition to opening up opportunities for trade in the domestic and international markets.(AU)

O artigo avalia o comportamento da produção e dos preços no mercado da pecuária de corte da Amazônia brasileira. Utilizaram-se dados de séries temporais obtidos em diversas fontes e submetidos às análises de regressão múltipla e regressão polinomial. Para a análise de preços utilizou-se o modelo clássico de séries temporais com a separação dos índices sazonais e cíclicos com base na média móvel centrada em doze meses. As análises abrangem o período de 1990 a 2015, fase em que o rebanho bovino regional evoluiu a uma taxa de 5% ao ano, frente a um crescimento de 1,7% do rebanho nacional. A análise de preços revelou a existência de ciclos na pecuária bovina regional, definidos, principalmente, pela correlação inversa entre o preço do boi gordo e o abate de matrizes. Quanto às análises das variáveis determinantes do crescimento da produção, configurado na expansão do rebanho, constatou-se que a política de crédito rural assumiu papel importante ao viabilizar a oferta de recursos para o financiamento de projetos pecuários que ganharam espaço frente aos investimentos em agricultura. A criação e estruturação das agências estaduais de defesa agropecuária, a partir do final da década de 1990, representou avanço importante na esfera institucional, pois ao executarem as políticas e programas de sanidade animal tem gerado um ambiente favorável para a expansão dos investimentos na produção e processamento, além de abrir oportunidades para comercialização no mercado interno, nacional e internacional.(AU)

Microbiota bacteriana de ovos de jacaré-do-pantanal incubados naturalmente / Bacterial microbiota of the Pantanal caiman eggs incubated in nature

A cadeia produtiva do Caiman yacare tem-se destacado no Mato Grosso com a exportação de 143.386 peles em 2015, cujo sistema de manejo (ranching) implica a incubação artificial dos ovos. Nesse processo, a contaminação bacteriana de ovos influencia a taxa de eclosão. O conhecimento da microbiota de ovos incubados naturalmente orienta o manejo sanitário adequado no incubatório. No presente estudo, são apresentadas informações sobre essa microbiota e sua correlação com a de outros crocodilianos, apontando-se as espécies com potencial patogênico. Amostras de 20 ninhos de C. yacare foram coletadas e semeadas em ágar sangue e ágar Mac Conckey. A colônia condizente com Salmonella sp. foi confirmada pela técnica de reação em cadeia de polimerase. Das 22 espécies bacterianas isoladas, 59% pertencem à família Enterobacteriaceae e 41% a outros táxons bacterianos. A semelhança dos achados com as bactérias isoladas na microbiota oral e/ou intestinal/cloacal de crocodilianos foi de 77,27%. As bactérias mais e menos frequentes foram, respectivamente, Bacillus cereus, Flavobacterium multivorum, Citrobacter freundii, Escherichia hermannii, Hafnia alvei, Morganella, morganni, Salmonella sp., Serratia marcescens e Shigella sonnei. Das bactérias isoladas, 86,36% têm potencial patogênico para crocodilianos. A origem materna e a ambiental da microbiota de ovos incubados naturalmente são, respectivamente, de 77,27% e 27,27%.(AU)

The Pantanal caiman productive chain has grown in Mato Grosso with the exportation of 143.383 leather pieces in 2015, whose management system (ranching) implies the artificial incubation of eggs. In this process, the bacterial contamination of the eggs influences the hatching rate. Knowledge of the naturally incubated microbiota of eggs guides the appropriate sanitary management in the incubator room. Here we present information about this microbiota and correlate it with that of other crocodilians, indicating the species with pathogenic potential. Samples were collected in 20 nests at Pantanal, and sown in blood and Mac Conckey agar. Salmonella sp. was confirmed through polymerase chain reaction technique. From the twenty-two different species of bacteria isolated, 59% are from the Enterobacteriaceae Family and 41% from other bacterial taxonomies. The similarity of findings to isolated bacteria in the crocodilians oral and/or intestinal/cloacal microbiota was of 77,27%. The most and least frequent bacteria were, respectively, Bacillus cereus, Flavobacterium multivorum and Citrobacter freundii and Escherichia hermannii, Hafnia alvei, Morganella, morganni, Salmonella sp., Serratia marcescens and Shigella sonnei. Among the isolated bacteria, 86,36% are pathogenic for crocodilians. The maternal and environmental origin of the microbiota of eggs naturally incubated is, respectively, of 77,27% and 27,27%.(AU)

Microbiota bacteriana de ovos de jacaré-do-pantanal incubados naturalmente / Bacterial microbiota of the Pantanal caiman eggs incubated in nature

A cadeia produtiva do Caiman yacare tem-se destacado no Mato Grosso com a exportação de 143.386 peles em 2015, cujo sistema de manejo (ranching) implica a incubação artificial dos ovos. Nesse processo, a contaminação bacteriana de ovos influencia a taxa de eclosão. O conhecimento da microbiota de ovos incubados naturalmente orienta o manejo sanitário adequado no incubatório. No presente estudo, são apresentadas informações sobre essa microbiota e sua correlação com a de outros crocodilianos, apontando-se as espécies com potencial patogênico. Amostras de 20 ninhos de C. yacare foram coletadas e semeadas em ágar sangue e ágar Mac Conckey. A colônia condizente com Salmonella sp. foi confirmada pela técnica de reação em cadeia de polimerase. Das 22 espécies bacterianas isoladas, 59% pertencem à família Enterobacteriaceae e 41% a outros táxons bacterianos. A semelhança dos achados com as bactérias isoladas na microbiota oral e/ou intestinal/cloacal de crocodilianos foi de 77,27%. As bactérias mais e menos frequentes foram, respectivamente, Bacillus cereus, Flavobacterium multivorum, Citrobacter freundii, Escherichia hermannii, Hafnia alvei, Morganella, morganni, Salmonella sp., Serratia marcescens e Shigella sonnei. Das bactérias isoladas, 86,36% têm potencial patogênico para crocodilianos. A origem materna e a ambiental da microbiota de ovos incubados naturalmente são, respectivamente, de 77,27% e 27,27%.(AU)

The Pantanal caiman productive chain has grown in Mato Grosso with the exportation of 143.383 leather pieces in 2015, whose management system (ranching) implies the artificial incubation of eggs. In this process, the bacterial contamination of the eggs influences the hatching rate. Knowledge of the naturally incubated microbiota of eggs guides the appropriate sanitary management in the incubator room. Here we present information about this microbiota and correlate it with that of other crocodilians, indicating the species with pathogenic potential. Samples were collected in 20 nests at Pantanal, and sown in blood and Mac Conckey agar. Salmonella sp. was confirmed through polymerase chain reaction technique. From the twenty-two different species of bacteria isolated, 59% are from the Enterobacteriaceae Family and 41% from other bacterial taxonomies. The similarity of findings to isolated bacteria in the crocodilians oral and/or intestinal/cloacal microbiota was of 77,27%. The most and least frequent bacteria were, respectively, Bacillus cereus, Flavobacterium multivorum and Citrobacter freundii and Escherichia hermannii, Hafnia alvei, Morganella, morganni, Salmonella sp., Serratia marcescens and Shigella sonnei. Among the isolated bacteria, 86,36% are pathogenic for crocodilians. The maternal and environmental origin of the microbiota of eggs naturally incubated is, respectively, of 77,27% and 27,27%.(AU)

Sustainable Cattle Ranching in Practice: Moving from Theory to Planning in Colombia's Livestock Sector.

A growing population with increasing consumption of milk and dairy require more agricultural output in the coming years, which potentially competes with forests and other natural habitats. This issue is particularly salient in the tropics, where deforestation has traditionally generated cattle pastures and other commodity crops such as corn and soy. The purpose of this article is to review the concepts and discussion associated with reconciling food production and conservation, and in particular with regards to cattle production, including the concepts of land-sparing and land-sharing. We then present these concepts in the specific context of Colombia, where there are efforts to increase both cattle production and protect tropical forests, in order to discuss the potential for landscape planning for sustainable cattle production. We outline a national planning approach, which includes disaggregating the diverse cattle sector and production types, identifying biophysical, and economic opportunities and barriers for sustainable intensification in cattle ranching, and analyzing areas suitable for habitat restoration and conservation, in order to plan for both land-sparing and land-sharing strategies. This approach can be used in other contexts across the world where there is a need to incorporate cattle production into national goals for carbon sequestration and habitat restoration and conservation.

Microbiota bacteriana de ovos de jacaré-do-pantanal incubados naturalmente

ABSTRACT The Pantanal caiman productive chain has grown in Mato Grosso with the exportation of 143.383 leather pieces in 2015, whose management system (ranching) implies the artificial incubation of eggs. In this process, the bacterial contamination of the eggs influences the hatching rate. Knowledge of the naturally incubated microbiota of eggs guides the appropriate sanitary management in the incubator room. Here we present information about this microbiota and correlate it with that of other crocodilians, indicating the species with pathogenic potential. Samples were collected in 20 nests at Pantanal, and sown in blood and Mac Conckey agar. Salmonella sp. was confirmed through polymerase chain reaction technique. From the twenty-two different species of bacteria isolated, 59% are from the Enterobacteriaceae Family and 41% from other bacterial taxonomies. The similarity of findings to isolated bacteria in the crocodilians oral and/or intestinal/cloacal microbiota was of 77,27%. The most and least frequent bacteria were, respectively, Bacillus cereus, Flavobacterium multivorum and Citrobacter freundii and Escherichia hermannii, Hafnia alvei, Morganella, morganni, Salmonella sp., Serratia marcescens and Shigella sonnei. Among the isolated bacteria, 86,36% are pathogenic for crocodilians. The maternal and environmental origin of the microbiota of eggs naturally incubated is, respectively, of 77,27% and 27,27%.

RESUMO A cadeia produtiva do Caiman yacare tem-se destacado no Mato Grosso com a exportação de 143.386 peles em 2015, cujo sistema de manejo (ranching) implica a incubação artificial dos ovos. Nesse processo, a contaminação bacteriana de ovos influencia a taxa de eclosão. O conhecimento da microbiota de ovos incubados naturalmente orienta o manejo sanitário adequado no incubatório. No presente estudo, são apresentadas informações sobre essa microbiota e sua correlação com a de outros crocodilianos, apontando-se as espécies com potencial patogênico. Amostras de 20 ninhos de C. yacare foram coletadas e semeadas em ágar sangue e ágar Mac Conckey. A colônia condizente com Salmonella sp. foi confirmada pela técnica de reação em cadeia de polimerase. Das 22 espécies bacterianas isoladas, 59% pertencem à família Enterobacteriaceae e 41% a outros táxons bacterianos. A semelhança dos achados com as bactérias isoladas na microbiota oral e/ou intestinal/cloacal de crocodilianos foi de 77,27%. As bactérias mais e menos frequentes foram, respectivamente, Bacillus cereus, Flavobacterium multivorum, Citrobacter freundii, Escherichia hermannii, Hafnia alvei, Morganella, morganni, Salmonella sp., Serratia marcescens e Shigella sonnei. Das bactérias isoladas, 86,36% têm potencial patogênico para crocodilianos. A origem materna e a ambiental da microbiota de ovos incubados naturalmente são, respectivamente, de 77,27% e 27,27%.

Understanding patterns of land-cover change in the Brazilian Cerrado from 2000 to 2015.

Clearing tropical vegetation impacts biodiversity, the provision of ecosystem services, and thus ultimately human welfare. We quantified changes in land cover from 2000 to 2015 across the Cerrado biome of northern Minas Gerais state, Brazil. We assessed the potential biophysical and socio-economic drivers of the loss of Cerrado, natural regeneration and net cover change at the municipality level. Further, we evaluated correlations between these land change variables and indicators of human welfare. We detected extensive land-cover changes in the study area, with the conversion of 23 446 km(2) and the natural regeneration of 13 926 km(2), resulting in a net loss of 9520 km(2) The annual net loss (-1.2% per year) of the cover of Cerrado is higher than that reported for the whole biome in similar periods. We argue that environmental and economic variables interact to underpin rates of conversion of Cerrado, most severely affecting more humid Cerrado lowlands. While rates of Cerrado regeneration are important for conservation strategies of the remaining biome, their integrity must be investigated given the likelihood of encroachment. Given the high frequency of land abandonment in tropical regions, secondary vegetation is fundamental to maintain biodiversity and ecosystem services. Finally, the impacts of Cerrado conversion on human welfare likely vary from local to regional scales, making it difficult to elaborate land-use policies based solely on socio-economic indicators.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'.

Assessing strategies to reconcile agriculture and bird conservation in the temperate grasslands of South America.

Globally, agriculture is the greatest source of threat to biodiversity, through both ongoing conversion of natural habitat and intensification of existing farmland. Land sparing and land sharing have been suggested as alternative approaches to reconcile this threat with the need for land to produce food. To examine which approach holds most promise for grassland species, we examined how bird population densities changed with farm yield (production per unit area) in the Campos of Brazil and Uruguay. We obtained information on biodiversity and crop yields from 24 sites that differed in agricultural yield. Density-yield functions were fitted for 121 bird species to describe the response of population densities to increasing farm yield, measured in terms of both food energy and profit. We categorized individual species according to how their population changed across the yield gradient as being positively or negatively affected by farming and according to whether the species' total population size was greater under land-sparing, land-sharing, or an intermediate strategy. Irrespective of the yield, most species were negatively affected by farming. Increasing yields reduced densities of approximately 80% of bird species. We estimated land sparing would result in larger populations than other sorts of strategies for 67% to 70% of negatively affected species, given current production levels, including three threatened species. This suggests that increasing yields in some areas while reducing grazing to low levels elsewhere may be the best option for bird conservation in these grasslands. Implementing such an approach would require conservation and production policies to be explicitly linked to support yield increases in farmed areas and concurrently guarantee that larger areas of lightly grazed natural grasslands are set aside for conservation.

Bird-habitat associations in coastal rangelands of southern Brazil / Associações entre aves e variáveis de habitat em campos costeiros do sul do Brasil

Nearly all remnants of temperate grasslands in southeastern South America are used for livestock ranching and are subject to habitat degradation resulting from this activity. Exploring how habitat features affect the composition of grassland avifaunal communities is a first step to understand how current cattle-ranching management practices impact avian diversity. We used canonical ordination to test for relationships between five habitat variables and the composition of the bird community in coastal grasslands in southern Brazil. We sampled pastures with different heights,from overgrazed short-grass to tall herbaceous vegetation. We recorded 1,535 individuals and 27 species of birds. The first ordination axis indicated a strong contribution of mean vegetation height on the composition of the bird community, whereas the second axis revealed the influence of herbaceous vegetation patchiness and woody vegetation cover. Three groups of species were revealed by the ordination: one more diffuse associated with intermediate and tall herbaceous vegetation, another with short grass, and a third with vegetation patchiness and woody vegetation. Species restricted to tall herbaceous vegetation are negatively impacted from habitat degradation resulting from overgrazing and trampling by livestock, and mowing and burning of tall plants. Occurrence of these species in our study area is related with the presence of swales immediately behind the dune system and where remnants of tall vegetation persist. Birds of pastures with ample cover of short herbaceous plants, including one globally threatened species and six other restricted to short-grass habitat, apparently benefit from local livestock management practices. Woody vegetation possibly functions as a keystone structure, enabling the occurrence in grasslands of avian species that rely on shrubby habitat. Although livestock ranching promotes the diversity of habitats by creating distinct patches of vegetation height in grasslands, current management practices directed to the maintenance of short grass pastures may eliminate an entire subset of species, including regionally threatened taxa, and reduce avian diversity. The maintenance of large patches of tall herbaceous plants is needed to ensure the survival of species reliant on this type of grassland structure in our study area.

Praticamente todos os remanescentes de campo temperado no sudeste da América do Sul são usados para a pecuária e estão sujeitos à degradação de habitat resultante dessa atividade. Explorar como a composição das comunidades de aves é influenciada por características de habitat é um passo inicial para compreender o impacto que as atuais práticas de manejo da pecuária em campos nativos exercem sobre a biodiversidade. Nós usamos ordenação canônica para testar as relações entre cinco variáveis de habitat e a composição da comunidade de aves em campos costeiros do sul do Brasil. Amostramos pastagens nativas de diferentes alturas, variando de campos sobrepastejados até aqueles cobertos por vegetação herbácea de porte elevado. Registramos 1.535 indivíduose 27 espécies de aves. O primeiro eixo de ordenação indicou uma forte contribuição de altura média da vegetação sobre a composição da comunidade de aves, enquanto o segundo eixo demonstrou a influência da variação vertical da altura da vegetação herbácea e da cobertura de vegetação lenhosa. Três grupos de espécies foram revelados pela ordenação: um mais difuso associado com vegetação herbácea de porte intermediário e alto, outro com vegetação baixa, e um terceiro relacionado com a variação vertical da altura da vegetação herbácea e a cobertura de vegetação lenhosa. Espécies restritas à vegetação herbácea de porte alto são impactadas negativamente pela degradação do habitat resultante do sobrepastejo e pisoteio, além de roçadas e queimadas. A ocorrência dessas aves em nossa área de estudo está relacionada à presença de depressões situadas imediatamente atrás do sistema de dunas e onde os remanescentes de vegetação alta persistem. Aves de pastagens com ampla cobertura de plantas herbáceas de porte baixo, incluindo uma espécie globalmente ameaçada e outras seis restritas a esse tipo de habitat, aparentemente se beneficiam das práticas locais de pecuária. A vegetação lenhosa possivelmente atua como uma estrutura-chave em campos, favorecendo a ocorrência de espécies que dependem de habitats arbustivos. Embora a pecuária promova a diversidade de habitats em campos ao criar um mosaico de manchas de vegetação de alturas variáveis, as atuais práticas de manejo voltadas para a manutenção de pastagens de gramíneas baixas podem eliminar um subconjunto inteiro de espécies, incluindo táxons regionalmente ameaçados, e reduzir a diversidade de aves em campos. A manutenção de grandes manchas de plantas herbáceas de porte alto é necessária para garantir a sobrevivência de espécies dependentes deste tipo de vegetação em nossa área de estudo.

Bird-habitat associations in coastal rangelands of southern Brazil / Associações entre aves e variáveis de habitat em campos costeiros do sul do Brasil

Nearly all remnants of temperate grasslands in southeastern South America are used for livestock ranching and are subject to habitat degradation resulting from this activity. Exploring how habitat features affect the composition of grassland avifaunal communities is a first step to understand how current cattle-ranching management practices impact avian diversity. We used canonical ordination to test for relationships between five habitat variables and the composition of the bird community in coastal grasslands in southern Brazil. We sampled pastures with different heights,from overgrazed short-grass to tall herbaceous vegetation. We recorded 1,535 individuals and 27 species of birds. The first ordination axis indicated a strong contribution of mean vegetation height on the composition of the bird community, whereas the second axis revealed the influence of herbaceous vegetation patchiness and woody vegetation cover. Three groups of species were revealed by the ordination: one more diffuse associated with intermediate and tall herbaceous vegetation, another with short grass, and a third with vegetation patchiness and woody vegetation. Species restricted to tall herbaceous vegetation are negatively impacted from habitat degradation resulting from overgrazing and trampling by livestock, and mowing and burning of tall plants. Occurrence of these species in our study area is related with the presence of swales immediately behind the dune system and where remnants of tall vegetation persist. Birds of pastures with ample cover of short herbaceous plants, including one globally threatened species and six other restricted to short-grass habitat, apparently benefit from local livestock management practices. Woody vegetation possibly functions as a keystone structure, enabling the occurrence in grasslands of avian species that rely on shrubby habitat. Although livestock ranching promotes the diversity of habitats by creating distinct patches of vegetation height in grasslands, current management practices directed to the maintenance of short grass pastures may eliminate an entire subset of species, including regionally threatened taxa, and reduce avian diversity. The maintenance of large patches of tall herbaceous plants is needed to ensure the survival of species reliant on this type of grassland structure in our study area.(AU)

Praticamente todos os remanescentes de campo temperado no sudeste da América do Sul são usados para a pecuária e estão sujeitos à degradação de habitat resultante dessa atividade. Explorar como a composição das comunidades de aves é influenciada por características de habitat é um passo inicial para compreender o impacto que as atuais práticas de manejo da pecuária em campos nativos exercem sobre a biodiversidade. Nós usamos ordenação canônica para testar as relações entre cinco variáveis de habitat e a composição da comunidade de aves em campos costeiros do sul do Brasil. Amostramos pastagens nativas de diferentes alturas, variando de campos sobrepastejados até aqueles cobertos por vegetação herbácea de porte elevado. Registramos 1.535 indivíduose 27 espécies de aves. O primeiro eixo de ordenação indicou uma forte contribuição de altura média da vegetação sobre a composição da comunidade de aves, enquanto o segundo eixo demonstrou a influência da variação vertical da altura da vegetação herbácea e da cobertura de vegetação lenhosa. Três grupos de espécies foram revelados pela ordenação: um mais difuso associado com vegetação herbácea de porte intermediário e alto, outro com vegetação baixa, e um terceiro relacionado com a variação vertical da altura da vegetação herbácea e a cobertura de vegetação lenhosa. Espécies restritas à vegetação herbácea de porte alto são impactadas negativamente pela degradação do habitat resultante do sobrepastejo e pisoteio, além de roçadas e queimadas. A ocorrência dessas aves em nossa área de estudo está relacionada à presença de depressões situadas imediatamente atrás do sistema de dunas e onde os remanescentes de vegetação alta persistem. Aves de pastagens com ampla cobertura de plantas herbáceas de porte baixo, incluindo uma espécie globalmente ameaçada e outras seis restritas a esse tipo de habitat, aparentemente se beneficiam das práticas locais de pecuária. A vegetação lenhosa possivelmente atua como uma estrutura-chave em campos, favorecendo a ocorrência de espécies que dependem de habitats arbustivos. Embora a pecuária promova a diversidade de habitats em campos ao criar um mosaico de manchas de vegetação de alturas variáveis, as atuais práticas de manejo voltadas para a manutenção de pastagens de gramíneas baixas podem eliminar um subconjunto inteiro de espécies, incluindo táxons regionalmente ameaçados, e reduzir a diversidade de aves em campos. A manutenção de grandes manchas de plantas herbáceas de porte alto é necessária para garantir a sobrevivência de espécies dependentes deste tipo de vegetação em nossa área de estudo.(AU)

Caracterização e avaliação da pastagem do rebanho de agricultores familiares do nordeste paraense / Characterization an evaluation of pastures and cattle at smallholder agriculturalists in northeast Pará State, Brazil

No Nordeste Paraense alguns agricultores familiares têm implantado pequenas áreas de pastagens e manejado pequenos rebanhos com o objetivo de aplicar eventuais ganhos obtidos com os cultivos, criando uma poupança a ser utilizada nas necessidades futuras da família ou da propriedade. Há indícios de problemas nas pastagens e no rebanho que limitam tanto a produção e a sustentabilidade da pecuária, como comprometem os cultivos agrícolas que realmente sustentam a propriedade. Este estudo tratou de identificar as principais limitações e propor alternativas de manejo que sejam econômica e ecologicamente mais sustentáveis. Na primeira fase do estudo, numa amostra ao acaso de 38 propriedades, descreveu-se o manejo da pastagem e do rebanho, e na segunda, numa amostra menor, de doze propriedades e por um período de 29 meses, avaliou-se o potencial desses dois componentes. As propriedades estudadas desenvolvem uma pecuária de baixa produtividade. Devido à baixa fertilidade do solo e o deficiente manejo, as pastagens não suprem os alimentos necessários ao rebanho, tanto em quantidade como em qualidade. Também foram identificadas deficiências no manejo do rebanho, próprias de sistemas extensivos. Contudo, as limitações podem ser solucionadas com práticas amplamente conhecidas de manejo da pastagem (como formação, manutenção e manejo) e do rebanho (reprodução, manejo de bezerros e sanidade em geral). Novos modelos de exploração também foram sugeridos.

In Northeastern Pará, smallholder agriculturalists have established small pastures and manage small herds, mainly with the objective of investing profits in their crops, as a form of savings to meet the family's and property's future needs. There are indications of pasture and herd problems that limit production and sustainability, and threaten the crops that really sustain the property. This study sought to identify constraints and technological solutions, and make information available for public policies. In the 1st phase of this study and using 38 smallholdings sampled at random, the pastures and herd management were described, and in the 2nd phase, with a smaller sample of 12 smallholdings during 29-month period, the potential of these two components was evaluated. In general, the smallholdings have low-productivity and ranching is vulnerable. Due to the low soil fertility and the deficient management, pastures do not supply all the herd's feed needs, neither in quantity nor quality. Herd management deficiencies are characteristic of extensive production systems. However, these constraints can be overcome with well-known technologies of pasture establishment, maintenance and management, and herd reproduction, calf management, and herd health, allowing significant improvement. New exploitation models were suggested also.

Caracterização e avaliação da pastagem do rebanho de agricultores familiares do nordeste paraense

In Northeastern Pará, smallholder agriculturalists have established small pastures and manage small herds, mainly with the objective of investing profits in their crops, as a form of savings to meet the family's and property's future needs. There are indications of pasture and herd problems that limit production and sustainability, and threaten the crops that really sustain the property. This study sought to identify constraints and technological solutions, and make information available for public policies. In the 1st phase of this study and using 38 smallholdings sampled at random, the pastures and herd management were described, and in the 2nd phase, with a smaller sample of 12 smallholdings during 29-month period, the potential of these two components was evaluated. In general, the smallholdings have low-productivity and ranching is vulnerable. Due to the low soil fertility and the deficient management, pastures do not supply all the herd's feed needs, neither in quantity nor quality. Herd management deficiencies are characteristic of extensive production systems. However, these constraints can be overcome with well-known technologies of pasture establishment, maintenance and management, and herd reproduction, calf management, and herd health, allowing significant improvement. New exploitation models were suggested also.

No Nordeste Paraense alguns agricultores familiares têm implantado pequenas áreas de pastagens e manejado pequenos rebanhos com o objetivo de aplicar eventuais ganhos obtidos com os cultivos, criando uma poupança a ser utilizada nas necessidades futuras da família ou da propriedade. Há indícios de problemas nas pastagens e no rebanho que limitam tanto a produção e a sustentabilidade da pecuária, como comprometem os cultivos agrícolas que realmente sustentam a propriedade. Este estudo tratou de identificar as principais limitações e propor alternativas de manejo que sejam econômica e ecologicamente mais sustentáveis. Na primeira fase do estudo, numa amostra ao acaso de 38 propriedades, descreveu-se o manejo da pastagem e do rebanho, e na segunda, numa amostra menor, de doze propriedades e por um período de 29 meses, avaliou-se o potencial desses dois componentes. As propriedades estudadas desenvolvem uma pecuária de baixa produtividade. Devido à baixa fertilidade do solo e o deficiente manejo, as pastagens não suprem os alimentos necessários ao rebanho, tanto em quantidade como em qualidade. Também foram identificadas deficiências no manejo do rebanho, próprias de sistemas extensivos. Contudo, as limitações podem ser solucionadas com práticas amplamente conhecidas de manejo da pastagem (como formação, manutenção e manejo) e do rebanho (reprodução, manejo de bezerros e sanidade em geral). Novos modelos de exploração também foram sugeridos.

Perfil de sensibilidade antimicrobiana in vitro de jurema preta e neem sobre amostras de staphylococcus sp. isoladas de mastite em búfalas

ABSTRACT Buffaloes ranching presents illnesses similar to those of cattle, such as mastitis, causing losses for the producers, in regard to therapeutics. The improper antibiotic use of antibiotics increases the bacterias resistance, making it increasingly more difficult to treat mastitis, owing to the need to discover new effective compounds. The present study was aimed to evaluate the alternative control of mastitis with plants of the semi-arid region of Paraiba State, Brazil: jurema preta [Mimosa tenuiflora (Wild) Poiret] and neem (Azadiracta indica). The leaves of neem were collected on farms in the county of Patos, and the bark of jurema preta was collected from the farm of the Federal University of Campina Grande UFCG, Campus of Patos, with subsequent preparation of the ethanolic extract. The samples of Staphylococcus sp. were collected from milk of buffaloes with subclinical mastitis and sown in Petri plates containing agar-base complemented by 8% of defibrinated sheep blood. The plates were incubatedin a bacteriological chamber at 37º C, and the reading was carried out at 24 and 48 hs. The assays were carried out in duplicate, and the final result was determined by the arithmetic mean of halo inhibition. The ethanolic extract of jurema preta was efficient when compared with that of neem, on coagulasenegative Staphylococcus isolated from cases of subclinical mastitis in buffaloes.

RESUMO Os bubalinos apresentam doenças semelhantes às de bovinos, como a mastite, causando grandes prejuízos pecuaristas, no que se refere a terapêutica. O uso indevido de antibióticos aumenta a resistência, o que torna cada vez mais difícil o tratamento da mastite, devido a necessidade de descobrir novos compostos que sejam eficazes. Este trabalho visa avaliar alternativa de tratamento da mastite com plantas do Semi-árido paraibano Jurema preta [ Mimosa tenuiflora (Wild) Poiret] e Neem (Azadiracta indica). As folhas de Neem foram coletadas em árvores de fazendas do Município de Patos, PB, e casca de Jurema preta foi da fazenda da Universidade Federal de Campina Grande, UFCG, Campus de Patos, em seguida, preparado o extrato etanólico. As amostras de Staphylococcus sp. foram coletadas de leite de búfalas com mastite subclínica e semeadas em placas de Petri contendo ágar-base acrescido de 8% de sangue desfibrinado de ovino. As placas foram incubadas em estufa bacteriológica a 37º C e a leitura foi realizada com 24 e 48h. Os ensaios foram realizados em duplicata e o resultado final foi determinado pela média aritmética dos halos de inibição. O extrato etanólico de Jurema preta foi eficaz quando comparado ao de Neem, sobre Staphylococcus coagulase negativa isolados de casos de mastite subclínica em búfalas.