Brucella is one of the major zoonotic pathogens worldwide, and it is responsible for enormous economic losses as well as considerable human morbidity in endemic areas. The organism infects animals such as swine, cattle, goat, sheep, and dogs. Humans can become infected indirectly through contact with infected animals or by animal products consumption. Brucellosis occurs worldwide, but it is well controlled in most developed countries. The disease is rare in industrialized nations because of routine screening of domestic livestock and animal vaccination programmes. Clinical disease is still common in the Middle East, Asia, Africa, South and Central America, the Mediterranean Basin, and the Caribbean. This review article aims to describe the prevalence of brucellosis in some countries where data are available around different regions of world, and risk factors associated infections according regression models.

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The aim of the present study was to estimate the prevalence and regional spread of bovine tuberculosis in the state of Minas Gerais, Brazil, to identify herd-level risk factors, and to provide guidance for disease control and mitigation of its impact in public health. The study comprised a large-scale random sample survey of 22,990 animals and 1586 herds, distributed in seven regions. A questionnaire was applied on each farm to collect epidemiological and herd management data. Overall, 5.04 % of herds and 0.81 % of animals were positive for bovine tuberculosis. The highest herd prevalence was found in Alto Paranaíba, an expanding dairy region. The more technologically advanced dairy herds showed a prevalence ratio of 2.83 compared to others and are obvious candidates for risk-based surveillance and herd accreditation schemes. Small farms cannot be left out of disease control efforts because they are the vast majority of herds, albeit with lower individual risk. With regard to public health, there is widespread practice of producing homemade fresh cheese with raw milk and of slaughtering culled cows in places without sanitary inspection. This poses a risk to consumers and limits the efficacy of surveillance at slaughter.

Low productivity cattle ranching, with its linkages to rural poverty, deforestation and greenhouse gas (GHG) emissions, remains one of the largest sustainability challenges in Brazil and has impacts worldwide. There is a nearly universal call to intensify extensive beef cattle production systems to spare land for crop production and nature and to meet Brazil's Intended Nationally Determined Contribution to reducing global climate change. However, different interventions aimed at the intensification of livestock systems in Brazil may involve substantial social and environmental tradeoffs. Here we examine these tradeoffs using a whole-farm model calibrated for the Brazilian agricultural frontier state of Mato Grosso, one of the largest soybean and beef cattle production regions in the world. Specifically, we compare the costs and benefits of a typical extensive, continuously grazed cattle system relative to a specialized soybean production system and two improved cattle management strategies (rotational grazing and integrated soybean-cattle) under different climate scenarios. We found clear tradeoffs in GHG and nitrogen emissions, climate resilience, and water and energy use across these systems. Relative to continuously grazed or rotationally grazed cattle systems, the integreated soybean-cattle system showed higher food production and lower GHG emissions per unit of human digestible protein, as well as increased resilience under climate change (both in terms of productivity and financial returns). All systems suffered productivity and profitability losses under severe climate change, highlighting the need for climate smart agricultural development strategies in the region. By underscoring the economic feasibility of improving the performance of cattle systems, and by quantifying the tradeoffs of each option, our results are useful for directing agricultural and climate policy.

The intensification of the livestock production system has gained prominence over the last decades. In addition to the reduction of grazing areas and increased productivity per hectare, the intercropping involving forest tree species and ruminants has been established as a sustainable production model, generating income and valuation of natural capital. Besides the social, economic, and environmental aspects, the animal welfare is a noteworthy factor. The objective of this study was to evaluate the microclimatic conditions in an open-pasture and in silvopastoral systems, considering the Temperature Humidity Index (THI) and alterations in animal behavior. Three different pasture arrangements were analyzed in this study: total absence of trees in an open-pasture (ArrA), presence of peripheral trees (Eucalyptus spp.) along the border fences (ArrB), and an intensive wooded area aggregated with pasture (ArrC). A herd of 24 crossbreed heifers (3/4 and 7/8 Holstein-Girolando breed) was evaluated. Behavior data were collected every 15 min starting at 08 h00 with readings ending at 16 h00. THI was used to evaluate the environmental comfort. The THI found in the system with open-pasture and in the two systems with silvopastoral arrangement reached critical levels. The two arrangements with eucalyptus rows were not capable of eliminating heat stress in the conditions found in the north region of Mato Grosso State although better conditions were obtained under the tree canopy. The differences between the microclimatic variables for the three arrangements modified the behavior of the animals regarding their location and activity, except for water consumption.