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1.
J. Anim. Behav. Biometeorol ; 11(3): e2023020, 2023. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1509909

Resumo

t Livestock body weight (BW) and average daily weight gain (ADG) are primary indicators of beef cattle productivity. The conventional method of weighing involves moving the cattle to a weighing location, which is labor-intensive, stressful for the animals and has a negative impact on their growth. An alternative approach is to use special weighing platforms attached to the drinkers to weigh the animals. This method enables daily monitoring of BW and ADG without incurring additional labor costs or stress. In this study, an experimental weighing platform, previously developed at KazATU and named after S. Seifullin, was employed to measure livestock's partial body weight (PBW). The weighing platform recorded the weights of the animals on the front legs at one-second intervals, allowing for subsequent calculation of the animals' total weight. However, due to significant weight fluctuations observed when the animals were on the platform, the accuracy of calculating the weight based on a simple average of the one-second measurements was questionable. Hence, an algorithm was developed to determine live weight by analyzing the primary data from the scales and identifying moments of animal immobility during drinking. The calculated results were compared with both mean and median values and data from Kazakhstan's information base of selection and breeding work (IBSBW). The experimental method exhibited a stronger correlation (r = 0.925) with the actual IBSBW data compared to the mean method (r = 0.887) or the median method (r = 0.921).(AU)


Assuntos
Animais , Comportamento Animal/fisiologia , Peso Corporal/fisiologia , Pastagens , Cazaquistão
2.
Acta sci., Anim. sci ; 45: e59494, 2023. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1428410

Resumo

To gain insights into the forage morphological and anatomical characteristics in a silvopastoral system (SPS) with Bolsa de Pastor (Zeyheria tuberculosa) and palisadegrass 'Marandu' (Urochloa brizantha) monoculture (MONO). The SPS was established through natural regeneration of the tree species. Treatments were a SPS and MONO distributed in a completely randomized design with six replicates and repeated measures were the harvest periods. Response variables were morpho-physiological and anatomical characteristicss: green: dead material ratio, leaf blade: stem+sheath ratio, leaf area index, chlorophyll and carotenoid concentrations, proportions of non-lignified and achlorophyllous areas, lignified areas in stems, proportions of non-lignified and achlorophyllous areas, lignified and chlorophyllous areas in leaves, as well as cell length in longitudinal section of stem. Morpho-physiological patterns were altered (p < 0.05) under natural shading conditions due to higher photosynthetic efficiency in the SPS. There was no effect (p > 0.05) of the systems on anatomical patterns, proportions of non-lignified and achlorophyllous, lignified and chlorophyllous tissues, these proportions were influenced only by the periods of the year, both for stems and leaves. Cells of the internodes of the grasses of the studied systems had the same length. The SPS alters morpho-physiological characteristics of palisadegrass and increases the concentration of chlorophyll a and b.(AU)


Assuntos
Fenômenos Fisiológicos Vegetais , Poaceae/anatomia & histologia , Pastagens
3.
Vet. Not. (Online) ; 29(1): e66886, 2023.
Artigo em Inglês | VETINDEX | ID: biblio-1418624

Resumo

This study compared three methods for estimating forage mass and its morphological components in canopies of Urochloa brizantha cv. Marandu (marandu palisadegrass). Two experiments were carried out, the fi rst simulating deferment and the second, continuous stocking. In the fi rst experiment, three methods for estimating forage mass (square, row, and tiller methods) were evaluated in different canopies with three initial heights (15, 30, and 45 cm). In the second experiment, two methods for estimating forage mass (square and tiller methods) were evaluated in canopies with three average heights (15, 30, and 45 cm) in summer. The experiments were conducted in a completely randomized design, in a split-plot scheme, with four replications. The plots were canopy heights and the subplots, the forage mass estimation methods. In general, taller canopies have greater forage mass. The tiller method resulted in lower total forage and senescent forage masses than the other methods. The tiller method underestimates total forage and senescent forage masses. The square and line methods are suitable to estimate the pasture total and senescent forage masses.(AU)


Este estudo comparou três métodos para a estimativa das massas de forragem e dos seus componentes morfológicos em dosséis de Urochloa brizantha cv. Marandu (capim-marandu). Dois experimentos foram realizados, sendo o primeiro simulando o diferimento e o segundo, a lotação contínua. No primeiro experimento, foram avaliados três métodos para estimativa de massa de forragem (métodos do quadrado, da linha e do perfilho) em dosséis diferidos com três alturas iniciais (15, 30 e 45 cm). No segundo experimento, foram avaliados dois métodos para estimativa de massa de forragem (métodos do quadrado e do perfilho) em dosséis com três alturas médias (15, 30 e 45 cm) no verão. Os experimentos foram conduzidos em delineamento inteiramente casualizado, em esquema de parcelas subdivididas, com quatro repetições. As parcelas foram as alturas dos dosséis e as subparcela, os métodos de estimativa da massa de forragem. Em geral, os dosséis mais altos apresentam maior massa de forragem. O método do perfilho resultou em massas de forragem total e de forragem senescente inferiores ao demais métodos. O método do perfilho subestima as massas de forragem total e de forragem senescente. Para estimar as massas de forragem total e de forragem senescente do pasto, os métodos do quadrado e da linha são adequados.(AU)


Assuntos
Biomassa , Poaceae/crescimento & desenvolvimento , 24444 , Pastagens
4.
Rev. bras. zootec ; 52: e20220052, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1449868

Resumo

The objective of this study was to evaluate the potential of improving the economic value of integrated crop-livestock systems (ICLS) compared to conventional systems specialized in monoculture. The experimental area was 16.02 ha, divided into 18 paddocks of 0.89 ha each, organized in a randomized block design, with three replicates and six models of production systems: crop system [corn ( Zea mays ) grain production], livestock system (beef cattle under grazing conditions), and four ICLS, identified as: ICLS-1, corn integrated with Marandu palisadegrass [ Urochloa brizantha (Hoechst. ex A. Rich.) R.D. Webster cv. Marandu (syn. Brachiaria brizantha cv. Marandu] sown simultaneously without herbicide; ICLS-2, corn and Marandu palisadegrass sown simultaneously with herbicide; ICLS-3, corn and Marandu palisadegrass with lagged sowing; and ICLS-4, corn and Marandu palisadegrass sown simultaneously, with herbicide in rows and between-rows of corn. We demonstrated the economic impact analysis combined with the risk optimization and discounted cash flow techniques based on Monte Carlo simulation, considering price and productivity uncertainties. The indicators of added value and return on investment of ICLS had an economic advantage compared with conventional systems. It was also found that ICLS needed a smaller operational area than conventional systems for the economic break-even point. Integrated systems provide lower financial and operational risk levels and greater economic value per hectare compared with conventional systems specialized in monoculture.(AU)


Assuntos
Indicadores Econômicos , Pastagens , Indicadores de Desenvolvimento Sustentável , Indústria Agropecuária/economia , Zea mays/crescimento & desenvolvimento
5.
Acta sci., Anim. sci ; 45: e59307, 2023. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1428317

Resumo

The objective was to assess the physiological and behavioral variables of pasture-raised Holstein heifers on the basis of their coat color. Eight heifers were used, four with black coat, and four with white coat. In the morning and afternoon periods, their physiological variables were measured, namely respiratory rate (RR, mov min. -1), rectal temperature (TR, ºC), and coat surface temperature (TS, ºC). The behavior analysis considered the site (sun or shade), position (standing or lying down), and activities (idleness, rumination, grazing, and others). The data of the physiological variables were assessed through analysis of variance, and significance, through Tukey's test at 5%, while behavioral data were assessed using the Chi-squared test (SAS Software). There was a difference for all of the heifers' physiological variables as a function of coat color (p < 0.0001) and period (p < 0.0001), with black ones showing greater results than white ones as to all physiological variables in the afternoon period (p < 0.0001). Grazing behavior is reduced during the hottest hours of the day. We conclude that solar radiation changes the physiological variables and grazing behavior of pasture-raised Holstein heifers.(AU)


Assuntos
Animais , Feminino , Bovinos/fisiologia , Pastagens , Radiação Solar , Comportamento Animal , Modalidades Fisiológicas
6.
Acta sci., Anim. sci ; 45: e57545, 2023. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1396846

Resumo

This study aimed to perform a strategic diagnosis on a property specialized in breeding, rearing and finishing beef cattle in the southern region of Piauí. It was conducted at Agropecuária Alvorada, located in the countryside, municipality of Bom Jesus, PI, Brazil. The farm develops the full cycle of beef cattle production, which is divided into breeding, rearing and finishing. A SWOT analysis (which stands for Strengths, Weaknesses, Opportunities and Threats) was carried out, consisting of an assessment of the property's internal and external environments. To evaluate the internal environment, an interview was held for data collection by means of questionnaires. The evaluation included: breeding management, sanitary management, nutritional management, infrastructure, workforce, technologies used in pasture formation, conservation and recovery, pasture management and zootechnical indices. To analyze the external environment, a group of people (experts) with deep knowledge of the subject addressed during the study was used as source of information. A matrix was generated with all the information from the SWOT analysis, strengths, weaknesses, opportunities and threats, culminating with the establishment of strategies to increase the productive efficiency of the cattle raising activity.(AU)


Assuntos
Animais , Bovinos/fisiologia , Criação de Animais Domésticos/métodos , Brasil , Pastagens
7.
Ciênc. anim. bras. (Impr.) ; 24: 73559P, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1430190

Resumo

The objective of this study was to evaluate the seasonal effect of months of the year upon the physiological and productive responses of crossbred dairy cows raised in an Amazonian climate. Twenty lactating cows were evaluated, fed on Brachiaria decumbens pasture, with free access to water and mineral supplementation. Data from climate variables air temperature (AT), relative humidity (RH), rainfall (RA) and temperature and humidity index (THI) were recorded dur ing the months of January to April 2019. The physiological data collected were: respiratory rate (RR, mov/min), heart rate (HR, beats/min), rectal temperature (RT, ºC), udder surface temperature (UST, ºC), body surface temperature (BST, ºC), dorsum surface temperature (DST, ºC), front surface temperature (FST, ºC) and rear shin temperature (RST). Milk production (MP) was also measured. There was a significant difference (P<0.05) of RST and RR with values ranging from 34.8 to 35.5°C and 32.0 to 36.2 mov/min, respectively. There were no significant difference (P>0.05) for BST, and the values for MP and THI were 3.8; 3.8; 4.6; 4.1 kg and 77.7; 79.7; 80.6; 80.1, respectively. It was concluded that there was a seasonal effect of the months of the year evaluated on the respiratory rate of animals, however, it did not change the MP and the THI. The Amazon environment is conducive to causing thermal stress in lactating cows raised on pasture, requiring the use of shading to facilitate the ability of these animals to dissipate heat.(AU)


O objetivo desse estudo foi avaliar os efeitos sazonais dos meses do ano sobre as respostas fisiológicas e produtivas de vacas leiteiras mestiças criadas em clima amazônico. Foram avaliadas 20 vacas lactantes, alimentadas com pasto de Brachiaria decumbens, com acesso livre a água e suplementação mineral. Foram registrados dados das variáveis climáticas temperatura do ar (TA), umidade relativa do ar (UR), precipitação pluviométrica (PP) e índice de temperatura e Umidade (ITU) durante os meses de janeiro a abril de 2019. Os dados fisiológicos coletados foram: frequência respiratória (FR, mov/min), frequência cardíaca (FC, bat./min), temperatura retal (TR, ºC), temperatura superficial do úbere (TSU, ºC), temperatura superfície corporal (TSC, ºC), temperatura superficial do dorso (TSD, ºC), temperatura superficial da fronte (TSF, ºC) e temperatura superficial da canela (TSCA, °C). Também foi mensurada a produção de leite (PL, kg). Houve diferença significativa (P<0,05) da TSCA e FR com valores variando de 34,8 a 35,5°C e 32,0 a 36,2 mov/min, respectivamente. Não houve diferença significativa (P>0,05) para TSC e os valores observados para PL e ITU foram 3,8; 3,8; 4,6; 4,1 kg e 77,7; 79,7; 80,6; 80,1, respectivamente. Houve efeito sazonal dos meses avaliados sobre a taxa respiratória dos animais, no entanto, isso não alterou a PL nem o ITU. O ambiente amazônico é propício a causar estresse térmico em vacas lactantes mantidas a pasto, sendo necessário o uso de sombreamento para facilitar a capacidade de dissipação de calor corporal desses animais.(AU)


Assuntos
Animais , Feminino , Bovinos/fisiologia , Modalidades Fisiológicas , Estações do Ano , Pastagens , Resposta ao Choque Térmico/fisiologia , Brachiaria
8.
Ciênc. anim. bras. (Impr.) ; 24: e-73410E, 2023. tab, graf
Artigo em Inglês, Português | VETINDEX | ID: biblio-1417940

Resumo

This study evaluates the economic viability of sheep finishing systems on irrigated Tamani grass pasture under continuous stocking, using castor bean cake. Four production systems were simulated: sheep supplemented with soybean meal on pasture fertilized with urea (SMUR), sheep supplemented with detoxified castor bean cake on pasture fertilized with urea (CCdUR), sheep supplemented with soybean meal on pasture fertilized with in natura castor bean cake (SMCC) and sheep supplemented with detoxified castor bean cake on pasture fertilized with in natura castor bean cake (CCdCC). A minimum unit of 3 hectares and an average slaughter weight of 28 kg were considered. A minimum selling price, at which the least profitable system would become profitable, was stablished: US$ 2.38 and US$ 4.45/kg per kilogram of body weight and carcass weight equivalent, adopting a minimum rate of return of 3.5% per year, based on the Selic rate. The costs for organic fertilization were 46.01% higher than in systems using chemical fertilization. The selling of live animals was not attractive in any of the systems evaluated, and the opposite was observed for the selling of carcasses and non-carcass components. System SMUR proved to be more profitable, with a gain of US$ 0.53 per kg carcass.


Objetivou-se avaliar a economicidade de sistemas de terminação de ovinos em pastagem irrigada de capim-tamani sob lotação contínua, utilizando torta de mamona. Foram simulados quatro sistemas de produção: ovinos suplementados com farelo de soja e o pasto adubado com ureia (FSUR), ovinos suplementados com torta de mamona destoxificada e o pasto adubado com ureia (TMdUR), ovinos suplementados com farelo de soja e o pasto adubado com torta de mamona in natura (FSTM) e ovinos suplementados com torta de mamona destoxificada e o pasto adubado com torta de mamona in natura (TMdTM). Foi considerada a unidade mínima de 3 hectares e determinado um peso médio ao abate de 28 kg de peso corporal. Estabeleceu-se um preço de venda mínimo, no qual o sistema de criação menos lucrativo se tornasse rentável de 2,38 e 4,45 dólares por quilograma de peso corporal e por equivalente de peso da carcaça, dotando uma taxa mínima de atratividade de 3,5% ao ano, com base na taxa Selic. Os custos com adubação orgânica, em média, são 46,01% superiores aos sistemas que utilizam adubação química. A venda de animais vivos não é atrativa em nenhum dos sistemas avaliados, sendo o contrário observado para a comercialização de carcaças e dos não componentes da carcaça de ovinos. O sistema de produção FSUR se mostrou mais lucrativo, com ganho de US$ 0.53 centavos por kg de carcaça.


Assuntos
Animais , Ricinus/química , Ovinos/crescimento & desenvolvimento , Suplementos Nutricionais/análise , Criação de Animais Domésticos/economia , Pastagens
9.
Rev. bras. zootec ; 52: e20220055, 2023. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1449869

Resumo

The purpose of this study was to evaluate the performance of beef cattle with two levels of energy-protein supplementation of low-consumption on African Bermudagrass pasture, overseeded in winter with oat and ryegrass, with or without irrigation. Twenty-four castrated Angus steers (11 months old and had an initial average of 220 kg body weight (BW)) were used in experimental area of 3.6 ha. The experiment was completely randomized in a 2×2 factorial design, with three replicates. The evaluation period was 249 days (July/2019 to March/2020). The treatments were: irrigated pasture with supplementation of 1 g/kg BW or 2.7 g/kg BW and non-irrigated pasture with 1 g/kg BW of supplement or 2.7 g/kg BW. The grazing method was continuous with a variable stocking rate. Irrigation provided pastures with better chemical composition in winter and spring. Irrigation increased the daily accumulation rate in winter (84.6 vs. 45.9 kg DM/ha/day), providing a greater stocking rate (1,702 vs. 1,385 kg/ha) and, consequently, body weight gain per hectare. Supplementation of 2.7 g/kg BW provided a greater stocking rate in winter (1,652 vs. 1,435 kg/ha) and spring (3,096 vs. 2,811 kg/ha), not changing in summer. The association of irrigation and supplementation of 2.7 vs. 1.0 g/kg BW improves the intake pattern by the animal in summer without changing productivity parameters. Irrigation increases productivity and the nutritional value of pasture with higher livestock production per area in periods of water deficit. The supply of 2.7 vs. 1.0 g/kg BW provides a greater stocking rate and body weight gain per hectare.(AU)


Assuntos
Animais , Bovinos/fisiologia , Pastagens , Ingestão de Alimentos/fisiologia , Cynodon/química , Irrigação Agrícola/métodos , Valor Nutritivo/fisiologia
10.
Rev. bras. zootec ; 52: e20210051, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1449863

Resumo

The objective of our study was to evaluate the effect of the use of legume (Arachis pintoi) or nitrogen fertilization on animal performance, characteristics of carcass and meat, and fatty acids profile of crossbred steers on Megathyrsus maximus cv. Aruana pasture, overseeded with temperate grasses. The experimental design was completely randomized, with three treatments and three replicates. The experiment was carried out from June to October (127 d). The treatments were: Low-N: 100 kg of N/ha; Medium-N: 200 kg of N/ha; and Legume: Arachis pintoi + 100 kg of N/ha. The pasture with higher nitrogen fertilization (N200) showed a more significant forage mass yield. The mixed grass with legumes presented a higher concentration of saturated fatty acids and saturated:unsaturated ratio in the meat. However, the grass pastures resulted in a higher content of unsaturated fatty acids in the meat. The other pasture variables, and characteristics of carcass and meat were not influenced by the treatments. The increase in nitrogen fertilization, from 100 to 200 kg/ha, and Arachis pintoi mixed with Aruana grass pasture overseeded with black oat and ryegrass does not affect the daily weight gain and the carcass and meat characteristics of the steers. The grass-legume mixture decreases the total concentration of unsaturated fatty acids in meat without influencing the concentration of polyunsaturated fatty acids.(AU)


Assuntos
Animais , Bovinos/fisiologia , Compostagem/métodos , Pastagens , Ingestão de Alimentos/fisiologia , Compostos de Nitrogênio/química , Poaceae/fisiologia , Fabaceae/química
11.
Ciênc. rural (Online) ; 53(2): 1-9, 2023. mapas, tab
Artigo em Inglês | VETINDEX | ID: biblio-1410723

Resumo

The extension of the area occupied by the inter tussock stratum and tussock stratum in natural pastures is essential for the productive performance of grazing animals. Images obtained from unmanned remote sensors can provide useful information, especially because they have a high spatial resolution. Thus, this study evaluated the performance of the supervised adaptive classification applied to aerial images obtained from an onboard drone camera to map the area covered by tussocks in a natural pasture of the Pampa biome. The study was carried out in a natural pasture area managed since 1986 under different forage allowances, considering treatments of 8, 12, and 16 kg of dry matter per 100 kg live weight (% LW). An aerial image from September 2017, obtained with a Canon S100 camera onboard a drone at an altitude of 120 m, with a spatial resolution of 5 cm, was used. The random forest and support vector machine classifiers were tested associated with specific classification rules. False-color images showed considerable visual similarity in the large patterns of the vegetation distribution and the validation performed with independent samples when compared to the classified images. The tested classifiers were able to measure the area covered by the tussock stratum, which could be an indicator of the quality vegetation in a natural grassland of the Pampa biome.


A quantidade de área ocupada por estrato inferior e superior em pastagens naturais tem grande importância sobre o desempenho produtivo dos animais em pastejo. Imagens obtidas de sensores remotos não tripulados podem fornecer informações úteis, especialmente por possuírem alta resolução espacial. O objetivo deste trabalho foi avaliar o desempenho de classificação supervisionada adaptativa aplicada a imagem aérea obtida por câmera a bordo de drone, no mapeamento da área coberta por touceiras em pastagem natural do bioma Pampa. O estudo foi realizado em área de pastagem natural, manejada desde 1986 sob diferentes ofertas de forragem, tendo sido considerados os tratamentos 8, 12 e 16 kg de matéria seca por 100 kg de peso vivo (% PV). Foi utilizada uma imagem aérea, de setembro de 2017, obtida com uma câmera Canon S100, a bordo de um drone a 120 m de altitude, correspondendo a resolução espacial de 5 cm. Foram testados dois classificadores, Random Forest e Support Vector Machine associados a regras específicas de classificação. As imagens de falsa cor, quando comparadas às imagens classificadas, apresentaram considerável semelhança visual nos grandes padrões de distribuição da vegetação, bem como na validação feita com amostras independentes. Os classificadores testados foram capazes de mensurar a área coberta por estrato superior, podendo ser um indicador da qualidade da vegetação, em pastagem natural do bioma Pampa.


Assuntos
Pastagens , Classificação , Sensores Remotos , Dispositivos Aéreos não Tripulados
12.
Ciênc. rural (Online) ; 53(6): 1-10, 2023. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1413140

Resumo

This study determined whether Canopeo and GreenSeeker measurements in Megathyrsus maximus can estimate plant height, dry matter mass, morphological components, and content of crude protein and neutral detergent fiber at different days of growth. Five plots of 5 × 25m M. maximus grass were defined: subplots of 1×1m were evaluated every three days, in which the pasture shows 3, 6, 9, 12, 15, 18, 21, 24, 27, and 30 days of regrowth. The subplot was evaluated for canopy height and mass accumulation. The canopeo index (CI) obtained at a higher height was lower than those obtained at a smaller height. Higher measurement height increased the normalized difference vegetation index (NDVI) relative to 0.10 m. The highest indexes were observed since 18 d of regrowth. Except for the CI evaluated at 0.10 m of height, the indexes were not correlated to the chemical composition of the forage. The CI and NDVI were positively correlated to plant height, dry matter mass, and leaf index, whereas both were negatively correlated with stalk index. Thus, lower evaluation heights for CI and NDVI can be a good predictor of forage height. Values of 0.83 and 85.8 for NDVI and CI, respectively, indicated an appropriate time to start the grazing of M. maximus.


O presente estudo teve como objetivo avaliar se os índices obtidos com Canopeo e GreenSeeker (NDVI) em Megathyrsus maximum são capazes de estimar altura de plantas, massa de matéria seca, componentes morfológicos e teor de proteína bruta e fibra em detergente neutro em diferentes dias de crescimento. Cinco parcelas de 5 × 25 m de capim M.maximum foram definidas: sub parcelas de 1 × 1 m foram avaliadas a cada três dias, nas quais a pastagem apresenta 3, 6, 9, 12, 15, 18, 21, 24, 27 e 30 dias de rebrota. A sub parcela foi avaliada quanto à altura do dossel e acúmulo de massa. O índice do Canopeo (IC) obtido em maior altura foi menor do que o obtido em menor altura. A maior altura de medição aumentou o NDVI em relação a 0,10 m. Os maiores índices foram observados desde 18 dias de rebrota. Exceto para o IC avaliado a 0,10 m de altura, os índices não foram correlacionados com a composição química da forragem. IC e NDVI correlacionaram-se positivamente com a altura da planta, massa de MS e índice foliar, e negativamente com o índice de colmos. Assim, menores alturas de avaliação para IC e NDVI podem ser um bom preditor da altura da forragem. Valores de 0,83 e 85,8 para NDVI e IC, respectivamente, indicam um momento adequado para o início do pastejo de Megathyrsus maximum.


Assuntos
Software , Pastagens
13.
Ciênc. rural (Online) ; 53(1): 1-9, 2023. graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1410516

Resumo

The objective was to evaluate the effect of nitrogen fertilization levels on productivity, and nutritional value of BRS Kurumi managed at different residue heights during rainy and dry periods of the year. The pasture was managed in three residue heights (20, 35, and 50 cm) and three nitrogen fertilization levels (0, 100, and 200 kg N/ha/year) during the rainy and dry seasons. When the height of the grass of each plot reached 80 cm, the Kurumi was cut manually at the pre-established residue heights. Around 89% of the dry matter (DM) production was observed during the rainy season. The residue height of 35 cm together with doses of 100 or 200 kg N/ha/year, and the residue height of 20 cm, with a dose of 100 kg N/ha/year were the treatments that had the highest DM production during the rainy period. No differences in DM production were observed between tested treatments during the dry period. The Kurumi cultivated during the dry period had the highest content of neutral detergent fiber and lowest digestibility. The Kurumi managed with residue heights of 20 and 35 cm and fertilized with 100 kg N/ha had the highest values of efficiency of utilization applied nitrogen. The use of 20 or 35 cm of residue height and 100 kg of N/ha/year is recommended to obtain greater biomass production and nutrients, nutritional quality, and nitrogen use efficiency.


O objetivo foi avaliar o efeito dos níveis de fertilização nitrogenada na produtividade e no valor nutritivo do BRS Kurumi quando manejado em diferentes alturas de resíduos durante os períodos seco e chuvoso do ano. O capim foi manejado em três alturas de resíduos (20, 35 e 50 cm) em associação com três níveis de fertilização com nitrogênio (0, 100 e 200 kg N/ha/ ano), durante o período seco e chuvoso do ano. Quando a altura do capim de cada parcela atingiu 80 cm, o Kurumi foi cortado nas alturas de resíduos pré-estabelecidas. Cerca de 89% da produção de MS foi observada durante o período chuvoso. A altura do resíduo de 35 cm juntamente com doses de 100 ou 200 kg N/ ha/ ano, e a altura do resíduo de 20 cm, com dose de 100 kg N/ha/ ano foram os tratamentos que apresentaram maior produção de MS durante o período chuvoso. Não foram observadas diferenças na produção de MS entre os tratamentos testados durante o período da seca. O Kurumi cultivado no período da seca apresentou maior teor de fibra em detergente neutro e menor digestibilidade. O Kurumi manejado com alturas de resíduo de 20 e 35 cm e fertilizado com 100 kg N/ha apresentou os maiores valores de eficiência de utilização do nitrogênio aplicado. Recomenda-se a utilização de 20 ou 35 cm de altura do resíduo e 100 kg de N/ha/ ano para obter maior produção de biomassa e nutrientes, qualidade nutricional e eficiência no uso do nitrogênio.


Assuntos
Estações do Ano , Pastagens , Fertilização , Poaceae , Nitrogênio
14.
Colloq. Agrar ; 18(4): 33-42, jul.-dez. 2022. ilus, tab, graf
Artigo em Português | VETINDEX | ID: biblio-1432774

Resumo

The low natural fertility and compaction of agricultural soils in the Cerrado are the main limitations for agricultural production. Changes in management systems are necessary to optimize the use of natural resources. The objective of this study was to map and evaluate the presence of penetration resistance and its relationship with soil chemical attributes in pasture areas in the Cerrado of Piauí. The experiment was carried out in the municipality of Corrente-PI, Brazil. The areawas divided into two sub-areas of 0.5 ha each: the first is remaining vegetation and the second is pasture. Fifty soil samples were collected in the 0.00-0.20 and 0.20-0.40 mlayers, with a sampling grid of 10 x 10 m. The pHin water, organic matter, calcium, magnesium,and soil penetration resistance were analyzed. The introduction of animals in the pasture area increased soil compaction by 2%. Chemical attributes, pH, organic matter, calcium and magnesium vary according to soil compaction by 2%. The native forest area has soil penetration resistance at acceptable levels (<2MPa)and availability of nutrientsat adequate levels. The maps of variability of organic matter, calcium, magnesium and penetration resistanceshowed the heterogeneity of the areas, allowing decisions based on specific management zones, localized application of nutrients and decompaction,and recovery of areas with inefficient management.(AU)


A baixa fertilidade natural e a compactação dos solos agrícolas do cerrado são as principais limitações para produção agropecuária. Mudanças nos sistemas de manejo são necessárias para otimização do uso de recursos naturais. O objetivo do estudo foi mapear e avaliar a presença da resistência a penetração e sua relação com os atributos químicos do solo em áreas de pastagens no cerrado piauiense. O experimento foi realizado no município de Corrente-PI. A área foi dividida em duas subáreas de 0,5 ha cada: a primeira é de vegetação remanescente, e a segunda de pastagem. Foram retiradas 50 amostras de solos nas camadas: 0.00-0.20 e 0.20-0.40 m, com malha amostral de 10 x 10 m. Foramanalisados, pH em água, matéria orgânica, cálcio, magnésio e resistência do solo a penetração. A introdução de animais na área de pastagem, aumentou a compactação do solo em 2%. Os atributos químicos, pH, matéria orgânica, cálcio e magnésio, variam de conforme a compactação do solo em 2%. A área de mata nativa apresenta resistência do solo à penetração em níveis aceitáveis (<2MPa)e disponibilidade de nutrientes em níveis adequados. Os mapas de variabilidade espacial mostraram a heterogeneidade das áreas,permitindo decisões baseadas em zonas específicas de manejo, aplicação de nutrientes e descompactação localizada e recuperação das áreascom manejo ineficiente.(AU)


Assuntos
Pastagens , Química do Solo , Mapeamento Geográfico , Brasil
15.
Vet. zootec ; 29: 1-14, 2022. tab
Artigo em Português | VETINDEX | ID: biblio-1400184

Resumo

A infestação de capim-annoni (Eragrostis plana Ness) nas áreas de pastejo em campo nativo ameaça a preservação do Bioma Pampa e a atividade pecuária no Rio Grande do Sul (RS). O objetivo deste trabalho foi avaliar a influência de tratamentos de adubação e calagem sobre a competitividade de espécies forrageiras do campo nativo com o capim-annoni, em área infestada pela invasora. Foi realizado um experimento em área de campo nativo infestada com capim-annoni no Centro de Pesquisa do DDPA/SEAPDR em Viamão - RS, sem uso de herbívoros domésticos, para avaliação do efeito dos tratamentos sem interferência do pastejo seletivo. Foram avaliados quatro tratamentos: TO sem adubação e calagem: T1 ­ apenas calagem: T2 - com adubação (nitrogênio, fósforo e potássio) e calagem; T3 - adubação com o dobro da dose de fósforo, mais potássio e calagem. Foram acompanhadas a evolução da composição botânica e o desenvolvimento das espécies do campo nativo e do capim-annoni por dois anos, pela avaliação da cobertura vegetal do solo e da produção de massa seca, como também as modificações da fertilidade do solo. Os resultados de produção de massa seca mostraram que a adubação nitrogenada do tratamento T2 beneficiou o crescimento do campo nativo e desfavoreceu o capim-annoni. Com a adubação nitrogenada do tratamento T2, espécies de gramíneas cespitosas do campo nativo atingiram maior altura e provavelmente competiram com o capim-annoni por meio de sombreamento, resultando na redução do crescimento da invasora.


The invasion of tough lovegrass (Eragrostis plana Ness) in native grassland grazing areas threatens the preservation of the Pampa biome as well as livestock farming in Rio Grande do Sul (RS), Brazil. The objective of the present study was to evaluate the influence of fertilization and liming treatments on the competitiveness of native grassland forage species with tough lovegrass, in an area infested by the invader. An experiment was carried out in a native grassland area infested with tough lovegrass that was not subjected to domestic herbivores at the DDPA/SEAPDR Research Center in Viamão - RS, to evaluate the effects of the treatments without interference from selective grazing. The following four treatments were assessed: TO - no fertilization or liming: T1 - liming only; T2 - fertilization (nitrogen, phosphorus and potassium) and liming; and T3 - fertilization with double the phosphorus dose, plus potassium and liming. The evolution of botanical composition and development of native grassland species and tough lovegrass were monitored for two years, by evaluating soil vegetal coverage and dry mass production, as well as modifications of soil fertility. The dry mass production results showed that nitrogen fertilization from T2 treatment benefited the growth of native grassland species and disfavored tough lovegrass. With nitrogen fertilization from T2 treatment, native grassland tufted grass species grew taller and probably competed with tough lovegrass through shading, resulting in reduced growth of the invader.


La infestación del capim annoni (Eragrostis plana Ness) en áreas de pastoreo en pastizales nativos amenaza la preservación del Bioma Pampa y la actividad ganadera en Rio Grande do Sul (RS), Brasil. El objetivo de este trabajo fue evaluar la influencia de los tratamientos de fertilización y encalado sobre la competitividad de las especies forrajeras del campo nativo con el capim annoni, en un área infestada por el invasor. Se realizó un experimento en un área de campo nativo infestado con capim annoni en el Centro de Investigación del DDPA/SEAPDR en Viamão - RS, sin el uso de herbívoros domésticos, para evaluar el efecto de los tratamientos sin la interferencia del pastoreo selectivo. Se evaluaron cuatro tratamientos: TO sin fertilización y encalado; T1 sólo encalado; T2 con fertilización (nitrógeno, fósforo y potasio) y encalado; T3 - fertilización con doble dosis de fósforo, más potasio y encalado. La evolución de la composición botánica y el desarrollo de las especies del campo nativo y del capim annoni fueron seguidos durante dos años, mediante la evaluación de la cobertura vegetal del suelo y la producción de masa seca, así como las modificaciones en la fertilidad del suelo. Los resultados de la producción de masa seca mostraron que la fertilización nitrogenada del tratamiento T2 benefició el crecimiento del campo nativo y perjudicó al capim annoni. Con la fertilización nitrogenada del tratamiento T2, las especies gramíneas cespitosas del campo nativo alcanzaron una mayor altura y probablemente compitieron con el capim annoni mediante el sombreado, lo que resultó en la reducción del crecimiento de la planta invasora.


Assuntos
Qualidade do Solo , Pastagens , Solos Calcários , Eragrostis , Brasil , Espécies Introduzidas , Esterco
16.
Sci. agric ; 79(2): e20200240, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1290180

Resumo

This work aimed to isolate and characterize plant growth promoting rhizobacteria (PGPR) from 10 Paspalum genotypes and evaluate the effect of their inoculation on P. regnellii, P. atratum, and P. malacophyllum genotypes. The bacterial population ranged from undetectable to 107 bacterial cells per gram of fresh matter in the Paspalum genotypes. Initially, we isolated 164 bacteria from rhizospheric soil and roots of the Paspalum genotypes using media N-free LG agar plate, semi-solid NFb, and LGI. The isolates were characterized genetically and physiologically. The sequencing of 16S rRNA showed the presence of many genera, and some are new in association with Paspalum. The most common was Bacillus followed by Rhizobium, Paraburkholderia, Enterobacter, Cupriavidus, Pseudomonas, Dyadobacter and Acinetobacter. Thirty-eight per cent of isolates produced siderophores, 25 % produced solubilized phosphate, and only 9 % produced indolic compounds. Three greenhouse experiments were performed in randomized blocks with six replicates using representative bacterial strains isolated from P. regnellii, P. malacophyllum and P. atratum cv. Pojuca. We also included strain Sp245 (Azospirillum baldaniorum), uninoculated control, and nitrogen control (150 kg N ha−1). There was an increase of up to 53 % in shoot dry matter in P. regnellii inoculated with strain Sp245 and the shoots accumulated more N. In contrast, only small effects were observed for the other Paspalum genotypes inoculated with PGPR from the host genotypes. This study shows a high diversity of diazotrophic rhizosphere bacteria and suggests no strain specificity between the bacterial isolates and the Paspalum genotypes.


Assuntos
Pastagens , Paspalum , Bactérias Fixadoras de Nitrogênio/isolamento & purificação , Rizosfera
17.
Acta sci., Anim. sci ; 44: e53855, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1366560

Resumo

The objective was to evaluate the performance and ingestivebehavior of grazing sheep in the finishing stage, with supplementation in the period of water restriction. Fifteen male crossbred sheep were used in continuous pasture in Massai grass and supplied supplement formulated with 18% of crude protein in three levels (0.0; 0.3 and 0.6% of body weight), individually. Bromatological and fodder production analyses were performed, as well as foliar mass production, stem mass and senescent material mass. The performance and ingestive behavior of the animals were evaluated. The design was in four randomized blocks for the variables measured in the fodder. For the biometry, weight gain and behavior variables measured in the animals, the design was entirely randomized with five repetitions. The total forage mass production was 5512.41 kg ha-1, with 6.58% of crude protein, 79 38% of neutral detergent fiber and with 65% of foliar mass. The total weight gain and daily weight gain were higher in animals that received a supplement of 0.6% of body weight. In general, the animalsgrazed more in the morning period and the supplemented ones destined more time for rumination and leisure than the ones not supplemented.(AU)


Assuntos
Animais , Ovinos , Aumento de Peso , Pastagens , Ração Animal , Peso Corporal
18.
Rev. Ciênc. Agrovet. (Online) ; 21(2): 148-158, mar. 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1366263

Resumo

The study was conducted at the Amazon Research Center CIMAZ -MACAGUAL of the University of Amazonia, Colombia, with a tropical rain forest climate (Af). The behavior of Bos taurus, Bos indicus, and Caqueteño Creole cattle, the animals were observed in paddocks with three levels of scattered tree cover density. The pasture was composed of Braquiaria decumbenswith 35 days of regrowth. Direct observations were made from 9:00 a.m. to 5:00 p.m. with 10-minute intervals between the recording of the activities. The activity performed most often during the day by all of the animals was grazing under the sun, and those who pasture the most arethe Caqueteño Creole, followed by the Bos indicusand, finally, the Bos taurus. Ruminating was the second most important activity performed by the cattle, having presented the same tendency. In the paddocks with a low level of tree cover, the animals pasture more in the shade; this trend is more relevant among B. taurus cattle.Caqueteño Creole cattle dedicate less time to water consumption and rest, spending more time grazing, in the high and medium cover levels, they interrupt the grazing at noon for a shorter time compared to B. indicusand B. taurus; after 2 p.m., the creoles vertiginously increase grazing. At the high cover level, the peak of grazing of the Caqueteño Creoles is at 9 a.m. and from 1-1:30 p.m., while at the medium tree cover level, the peak of pasturing was at noon, 1:30 p.m., and 4:30 p.m., at the high tree level of cover, the peak for the three breeds was at 11 a.m. Only at the average tree level of cover did the Caquetaño creoles and B. indicuspresent a similar peak. In 9-9:30 a.m. and 4-5 p.m., the breeds substantially reduce rumination.(AU)


O estudo foi realizado no Centro de Pesquisa Amazônica CIMAZ -MACAGUAL da Universidade da Amazônia, Colômbia, com um clima de floresta tropical úmida (Af). O comportamento do gado Bos taurus, Bos indicuse Caqueteño crioulo, os animais foram observados em cercados com três níveis de densidade de cobertura arbórea dispersa. A pastagem era composta de Braquiaria decumbenscom 35 dias de recrescimento. Observações diretas foram feitas das 9h às 17h com intervalos de 10 minutos entre o registro das atividades.A atividade mais executada durante o dia por todos os animais era o pasto sob o sol, e aqueles que mais pastam são os Caqueteñocrioulo, seguido pelo Bos indicuse, finalmente, o Bos taurus. A ruminação foi a segunda atividade mais importante desempenhada pelo gado, tendo apresentado a mesma tendência. Nos cercados com um baixo nível de cobertura arbórea, os animais pastam mais à sombra; esta tendência é mais relevante entre o gado B. taurus.O gado crioulo Caqueteñodedica menos tempo ao consumo de água e descanso, passando mais tempo pastando, nos níveis de cobertura alta e média, interrompem o pastoreio ao meio-dia por um tempo mais curto em comparação com o B. indicuse B. taurus; depois das 14 horas, os crioulos aumentam vertiginosamente o pastoreio. No nível de cobertura alta, o pico de pastagem dos Caqueteñocrioulosé às 9h e das 13h30, enquanto no nível médio de cobertura de árvores, o pico de pastagem era ao meio-dia, 13h30 e 16h30, no nível alto de cobertura de árvores, o pico para as três raças era às 11h. Nas 9-9h30 e16-17h, as raças reduzem substancialmente a ruminação.(AU)


Assuntos
Animais , Bovinos , Comportamento Animal , Pastagens , Gado , Etologia
19.
Acta sci., Anim. sci ; 44: e53901, 2022. graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1366556

Resumo

The stockpiled forage canopy consists of tillers at different ages, which have specific development patterns. The objective was to understand the development of Urochloa brizanthacv. Marandu during the stockpiling period, by the morphogenic evaluation of tillers at different ages. The experiment was conducted in a completely randomized design, in a split plot scheme, with four replications. Three tillers ages (young, mature and old) and two periods of stockpiling (initial and final) were evaluated. The leaf appearance and elongation rates were higher in young tillers (0.05 tiller-1day-1and 0.62 cm tiller-1day-1, respectively), compared to old tillers (0.02 tiller leaf-1day-1and 0.20 cm tiller-1day-1, respectively). The final leaf length of the tillers' age groups was the same in the beginning of stockpiling. The number of live leaves was lower in the old tillers (2.4), compared to the young (3.6) and mature (4.1) ones, contrary to the stem length. The number of old tillers (800 tillers m-2) was higher than the young (299 tillers m-2) and mature ones (358 tillers m-²). The participation of different age groups of tillersin the canopy influences the development and structure of marandu palisadegrass.(AU)


Assuntos
Pastagens/análise , Poaceae/química , Morfogênese
20.
Semina ciênc. agrar ; 43(2): 541-560, mar.-abr. 2022. tab, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1368831

Resumo

The aim of this study was to analyze the production patterns present in rural properties producing cattle in the micro-regions that make up the state of Pará. Exploratory Factor Analysis (EFA) was applied to identify the patterns, and these data are used to evaluate correlation between the heterogeneity of rural properties and the environmental impact on the identified patterns. The theoretical contribution is based on discussions on global impacts of food production and environmental sustainability and the impacts of livestock production systems in Brazil and the Amazon. Survey data were taken from the 2017 Agricultural Census, available for the 144 municipalities in the state, and pooled into 22 micro-regions. Three patterns of rural properties were identified: the first related to conservation management practices and called transition management; the second highlights aspects associated with information technology and communication (ICT) and productivity called technical productive efficiency; the third indicates the importance of social organization and access to information called social participation. With these patterns, it was possible to develop the Traditional Performance Indicator (TPI), in which the micro-regions of São Félix do Xingu, Itaituba and Conceição do Araguaia were those with the highest values of this indicator, water protection practices are present in the properties, however, in precarious conditions, and conservation practices are rarely used. The correlation between heterogeneity, measured by the size of pasture area in each microregion, and the TPI is positive, strong and significant. In this transition context, public policies are essential to provide access to infrastructure, credit and good animal health and biotechnology practices.(AU)


O objetivo deste estudo foi analisar os padrões de produção presentes nos estabelecimentos rurais produtores de gado bovino nas microrregiões que formam o estado do Pará. Foi aplicada a técnica estatística de Análise Fatorial Exploratória (AFE) para identificar os padrões, e com esses dados avaliar a correlação entre a heterogeneidade das propriedades rurais produtoras e o impacto ambiental nos padrões identificados. O aporte teórico está ancorado nas discussões sobre os impactos globais da produção de alimentos e a sustentabilidade ambiental e os impactos da pecuária no Brasil e na Amazônia. Os dados da pesquisa foram extraídos do Censo Agropecuário de 2017, disponíveis para os 144 municípios do estado, e agregados em 22 microrregiões. Foram identificados três padrões de estabelecimentos rurais: o primeiro relacionado as práticas de gestão conservacionistas e denominado de gestão em transição; o segundo destaca aspectos associados a tecnologia de informática e comunicação (TIC) e a produtividade denominado de eficiência técnica produtiva; o terceiro indica a importância da organização social e o acesso a informação denominado de participação social. Com os resultados desses padrões foi possível gerar o Indicador de Desempenho Tradicional (IDT), em que as microrregiões de São Félix do Xingu, Itaituba e Conceição do Araguaia foram aquelas com maior nível desse indicador, as práticas de proteção das águas se fazem presente nas propriedades, porém, em condições precárias, e as práticas conservacionistas são pouco empregadas. A correlação entre a heterogeneidade, medida pelo tamanho da área de pasto em cada microrregião, e o IDT é positiva, forte e significativa. Nesse contexto de transição, as políticas públicas são essenciais para proporcionar acesso a infraestrutura, crédito e boas práticas de saúde animal e biotecnologia.(AU)


Assuntos
Animais , Bovinos , Biotecnologia , Pastagens , Indústria Agropecuária , Ecossistema Amazônico
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