Questões para Concursos

Many studies reveal the contributions of plant breeding and agronomy to farm productivity and their role in reshaping global diets. However, historical accounts also implicate these sciences in the creation of new problems, from novel disease vulnerabilities propagated through industrial monocrops to the negative ecological and public health consequences of crops dependent on chemical inputs and industrialized food systems more generally. Increasingly, historical analyses also highlight the expertise variously usurped, overlooked, abandoned, or suppressed in the pursuit of “modern” agricultural science. Experiment stations and “improved” plants were instruments of colonialism, means of controlling lands and lives of peoples typically labeled as “primitive” and “backward” by imperial authorities. In many cases, the assumptions of colonial improvers persisted in the international development programs that have sought since the mid-20th century to deliver “modern” science to farming communities in the Global South. Awareness of these issues has brought alternative domains of crop science such as agroecology to the fore in recent decades, as researchers reconcile the need for robust crop knowledge and know-how with the imperatives of addressing social and environmental injustice. Helen Anne Curry; Ryan Nehring. The history of crop science and the future of food. Internet: (adapted)

In the 20 th century, we made tremendous advances in discovering fundamental principles in different scientific disciplines that created major breakthroughs in management and technology for agricultural systems, mostly by empirical means. However, as we enter the 21st century, agricultural research has more difficult and complex problems to solve. The environmental consciousness of the general public is requiring us to modify farm management to protect water, air, and soil quality, while staying economically profitable. At the same time, market-based global competition in agricultural products is challenging economic viability of the traditional agricultural systems, and requires the development of new and dynamic production systems. Fortunately, the new electronic technologies can provide us a vast amount of real-time information about crop conditions and near-term weather via remote sensing by satellites or ground-based instruments and the Internet, that can be utilized to develop a whole new level of management. However, we need the means to capture and make sense of this vast amount of site-specific data. Our customers, the agricultural producers, are asking for a quicker transfer of research results in an integrated usable form for site-specific management. Such a request can only be met with system models, because system models are indeed the integration and quantification of current knowledge based on fundamental principles and laws. Models enhance understanding of data taken under certain conditions and help extrapolate their applications to other conditions and locations. Lajpat R. Ahuja; Liwang Ma; Terry A. Howell. Whole System Integration and Modeling — Essential to Agricultural Science and Technology in the 21st Century. In: Lajpat R. Ahuja; Liwang Ma; Terry A. Howell (eds.) Agricultural system models in field research and technology transfer . Boca Raton, CRC Press LLC, 2002 (adapted).

Climate change poses significant challenges to cattle farming, a sector vital to global food security. Among the most pressing concerns is the increasing frequency and intensity of droughts. Reduced rainfall diminishes pasture quality and availability, limiting feed for livestock and increasing water scarcity. This can lead to decreased animal growth rates, reduced milk production, and increased mortality rates. Moreover, prolonged droughts can contribute to desertification, shrinking available grazing land and forcing farmers to adopt costly alternative feeding strategies. Beyond drought, other climate-related impacts include heat stress, which can significantly impact animal health and productivity. Rising temperatures can exacerbate heat stress, leading to decreased feed intake, reduced fertility, and increased mortality in livestock. Furthermore, extreme weather events, such as heavy rainfall and flooding, can cause infrastructure damage, contaminate water sources, and lead to the loss of livestock. The cattle farming sector itself contributes to climate change through greenhouse gas emissions, primarily methane produced during animal digestion and nitrous oxide from manure management. Deforestation for pasture expansion also releases significant amounts of carbon dioxide. To address these challenges, a multi-pronged approach is crucial. • Genetic selection: Breeding programs focused on developing drought-resistant and heat-tolerant livestock breeds are vital. • Sustainable feeding strategies: Implementing precision feeding techniques, improving feed efficiency, and exploring alternative feed sources, such as drought-resistant forage varieties, can enhance livestock resilience. • Integrated farming systems: Integrating crop and livestock production, such as through agroforestry systems, can improve soil health, enhance water retention, and reduce greenhouse gas emissions. • Technological innovations: Utilizing technologies such as precision livestock farming, remote sensing for pasture monitoring, and renewable energy sources can improve resource efficiency and reduce the environmental footprint of cattle production. Furthermore, strong policy support, including incentives for sustainable farming practices, investments in research and development, and improved access to climate information services, are essential for the long-term sustainability of the cattle farming sector. Addressing the challenges posed by climate change requires a collaborative effort involving farmers, researchers, policymakers, and consumers. By embracing innovative solutions, prioritizing sustainable practices, and fostering a collective understanding of the importance of climate-resilient livestock production, we can ensure a future when this vital sector continues to thrive while minimizing its environmental impact. Internet: (adapted).

Climate change poses significant challenges to cattle farming, a sector vital to global food security. Among the most pressing concerns is the increasing frequency and intensity of droughts. Reduced rainfall diminishes pasture quality and availability, limiting feed for livestock and increasing water scarcity. This can lead to decreased animal growth rates, reduced milk production, and increased mortality rates. Moreover, prolonged droughts can contribute to desertification, shrinking available grazing land and forcing farmers to adopt costly alternative feeding strategies. Beyond drought, other climate-related impacts include heat stress, which can significantly impact animal health and productivity. Rising temperatures can exacerbate heat stress, leading to decreased feed intake, reduced fertility, and increased mortality in livestock. Furthermore, extreme weather events, such as heavy rainfall and flooding, can cause infrastructure damage, contaminate water sources, and lead to the loss of livestock. The cattle farming sector itself contributes to climate change through greenhouse gas emissions, primarily methane produced during animal digestion and nitrous oxide from manure management. Deforestation for pasture expansion also releases significant amounts of carbon dioxide. To address these challenges, a multi-pronged approach is crucial. • Genetic selection: Breeding programs focused on developing drought-resistant and heat-tolerant livestock breeds are vital. • Sustainable feeding strategies: Implementing precision feeding techniques, improving feed efficiency, and exploring alternative feed sources, such as drought-resistant forage varieties, can enhance livestock resilience. • Integrated farming systems: Integrating crop and livestock production, such as through agroforestry systems, can improve soil health, enhance water retention, and reduce greenhouse gas emissions. • Technological innovations: Utilizing technologies such as precision livestock farming, remote sensing for pasture monitoring, and renewable energy sources can improve resource efficiency and reduce the environmental footprint of cattle production. Furthermore, strong policy support, including incentives for sustainable farming practices, investments in research and development, and improved access to climate information services, are essential for the long-term sustainability of the cattle farming sector. Addressing the challenges posed by climate change requires a collaborative effort involving farmers, researchers, policymakers, and consumers. By embracing innovative solutions, prioritizing sustainable practices, and fostering a collective understanding of the importance of climate-resilient livestock production, we can ensure a future when this vital sector continues to thrive while minimizing its environmental impact. Internet: (adapted).

Climate change poses significant challenges to cattle farming, a sector vital to global food security. Among the most pressing concerns is the increasing frequency and intensity of droughts. Reduced rainfall diminishes pasture quality and availability, limiting feed for livestock and increasing water scarcity. This can lead to decreased animal growth rates, reduced milk production, and increased mortality rates. Moreover, prolonged droughts can contribute to desertification, shrinking available grazing land and forcing farmers to adopt costly alternative feeding strategies. Beyond drought, other climate-related impacts include heat stress, which can significantly impact animal health and productivity. Rising temperatures can exacerbate heat stress, leading to decreased feed intake, reduced fertility, and increased mortality in livestock. Furthermore, extreme weather events, such as heavy rainfall and flooding, can cause infrastructure damage, contaminate water sources, and lead to the loss of livestock. The cattle farming sector itself contributes to climate change through greenhouse gas emissions, primarily methane produced during animal digestion and nitrous oxide from manure management. Deforestation for pasture expansion also releases significant amounts of carbon dioxide. To address these challenges, a multi-pronged approach is crucial. • Genetic selection: Breeding programs focused on developing drought-resistant livestock breeds are vital. and heat-tolerant • Sustainable feeding strategies: Implementing precision feeding techniques, improving feed efficiency, and exploring alternative drought-resistant forage livestock resilience. feed sources, varieties, such as can enhance • Integrated farming systems: Integrating crop and livestock production, such as through agroforestry systems, can improve soil health, enhance water retention, and reduce greenhouse gas emissions. • Technological innovations: Utilizing technologies such as precision livestock farming, remote sensing for pasture monitoring, and renewable energy sources can improve resource efficiency and reduce the environmental footprint of cattle production. Furthermore, strong policy support, including incentives for sustainable farming practices, investments in research and development, and improved access to climate information services, are essential for the long-term sustainability of the cattle farming sector. Addressing the challenges posed by climate change requires a collaborative effort involving farmers, researchers, policymakers, and consumers. By embracing innovative solutions, prioritizing sustainable practices, and fostering a collective understanding of the importance of climate-resilient livestock production, we can ensure a future when this vital sector continues to thrive while minimizing its environmental impact. Internet: (adapted).

Climate change poses significant challenges to cattle farming, a sector vital to global food security. Among the most pressing concerns is the increasing frequency and intensity of droughts. Reduced rainfall diminishes pasture quality and availability, limiting feed for livestock and increasing water scarcity. This can lead to decreased animal growth rates, reduced milk production, and increased mortality rates. Moreover, prolonged droughts can contribute to desertification, shrinking available grazing land and forcing farmers to adopt costly alternative feeding strategies. Beyond drought, other climate-related impacts include heat stress, which can significantly impact animal health and productivity. Rising temperatures can exacerbate heat stress, leading to decreased feed intake, reduced fertility, and increased mortality in livestock. Furthermore, extreme weather events, such as heavy rainfall and flooding, can cause infrastructure damage, contaminate water sources, and lead to the loss of livestock. The cattle farming sector itself contributes to climate change through greenhouse gas emissions, primarily methane produced during animal digestion and nitrous oxide from manure management. Deforestation for pasture expansion also releases significant amounts of carbon dioxide. To address these challenges, a multi-pronged approach is crucial. • Genetic selection: Breeding programs focused on developing drought-resistant livestock breeds are vital. and heat-tolerant • Sustainable feeding strategies: Implementing precision feeding techniques, improving feed efficiency, and exploring alternative drought-resistant forage livestock resilience. feed sources, varieties, such as can enhance • Integrated farming systems: Integrating crop and livestock production, such as through agroforestry systems, can improve soil health, enhance water retention, and reduce greenhouse gas emissions. • Technological innovations: Utilizing technologies such as precision livestock farming, remote sensing for pasture monitoring, and renewable energy sources can improve resource efficiency and reduce the environmental footprint of cattle production. Furthermore, strong policy support, including incentives for sustainable farming practices, investments in research and development, and improved access to climate information services, are essential for the long-term sustainability of the cattle farming sector. Addressing the challenges posed by climate change requires a collaborative effort involving farmers, researchers, policymakers, and consumers. By embracing innovative solutions, prioritizing sustainable practices, and fostering a collective understanding of the importance of climate-resilient livestock production, we can ensure a future when this vital sector continues to thrive while minimizing its environmental impact. Internet: (adapted).

Grain poisoning of cattle and sheep Grain poisoning, also known as grain overload or lactic acidosis, is usually the result of stock consuming large quantities of grain or pellets to which they are unaccustomed. Pasture-fed cows or feedlot cattle not yet adapted to grain may become acutely ill or die after eating only moderate amounts of grain, whereas stock accustomed to diets high in grain content may consume large amounts of grain with little or no effect. Some circumstances under which grain poisoning can occur include: accidental access to grain stores; stock access to stubble paddocks containing excess grain after harvest; stock access to standing crops; cattle and sheep on feedlot rations without proper introduction; and grain feeding during drought without proper introduction. How is it caused? Grain and finely ground carbohydrate (such as found in pellets) is rapidly fermented by bacteria in the rumen, producing large quantities of lactic acid, which lowers the pH in the rumen. The build-up of acid has effects on the animal such as: there is a decrease in the numbers of useful bacteria in the rumen and an increase in the amount of acid-producing bacteria (causing further build-up of acid in the rumen), rumen contractions cease, lactic acid draws fluid into the rumen from the tissues and blood, resulting in dehydration, and, in severe cases, the blood may become more acid, resulting in heart failure, kidney failure and or even death. Grains with a higher fibre content, such as oats and sorghum, are safer to feed than, for example, wheat and barley, since the fibre slows the rate of digestion. Cracking grain increases the rate of digestion of the starch and consequently may increase the risk of grain poisoning. Any factor that causes variation in the intake of grain, or variation in the availability of carbohydrate, may lead to grain poisoning problems. For example, an unpalatable additive or inclement weather may put cattle off their feed on one day, but then they gorge the next day. The effects of grain poisoning may be worsened if the animal is also suffering from cold stress. It is a wise precaution to increase the proportion of roughage fed during particularly cold weather. Other sources of carbohydrates, such as apples, grapes, bread, baker’s dough and incompletely fermented brewer’s grain, can also cause poisoning if eaten in excess. Internet: (adapted).

Grain poisoning of cattle and sheep Grain poisoning, also known as grain overload or lactic acidosis, is usually the result of stock consuming large quantities of grain or pellets to which they are unaccustomed. Pasture-fed cows or feedlot cattle not yet adapted to grain may become acutely ill or die after eating only moderate amounts of grain, whereas stock accustomed to diets high in grain content may consume large amounts of grain with little or no effect. Some circumstances under which grain poisoning can occur include: accidental access to grain stores; stock access to stubble paddocks containing excess grain after harvest; stock access to standing crops; cattle and sheep on feedlot rations without proper introduction; and grain feeding during drought without proper introduction. How is it caused? Grain and finely ground carbohydrate (such as found in pellets) is rapidly fermented by bacteria in the rumen, producing large quantities of lactic acid, which lowers the pH in the rumen. The build-up of acid has effects on the animal such as: there is a decrease in the numbers of useful bacteria in the rumen and an increase in the amount of acid-producing bacteria (causing further build-up of acid in the rumen), rumen contractions cease, lactic acid draws fluid into the rumen from the tissues and blood, resulting in dehydration, and, in severe cases, the blood may become more acid, resulting in heart failure, kidney failure and or even death. Grains with a higher fibre content, such as oats and sorghum, are safer to feed than, for example, wheat and barley, since the fibre slows the rate of digestion. Cracking grain increases the rate of digestion of the starch and consequently may increase the risk of grain poisoning. Any factor that causes variation in the intake of grain, or variation in the availability of carbohydrate, may lead to grain poisoning problems. For example, an unpalatable additive or inclement weather may put cattle off their feed on one day, but then they gorge the next day. The effects of grain poisoning may be worsened if the animal is also suffering from cold stress. It is a wise precaution to increase the proportion of roughage fed during particularly cold weather. Other sources of carbohydrates, such as apples, grapes, bread, baker’s dough and incompletely fermented brewer’s grain, can also cause poisoning if eaten in excess. Internet: (adapted).