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This work evaluated if strategic control based on no more than three or four annual treatments is useful to control Rhipicephalus microplus infestations on cattle when it is applied to intensive rotational grazing and silvopastoral systems with high stocking rates in subtropical areas. In the intensive rotational grazing system, three annual treatments with chemical acaricides were applied on cattle in two different schemes: between spring and early summer and from late winter and late spring. Strategic control based on three treatments with chemical acaricides from late winter to late spring plus an additional fourth treatment in summer was tested in the silvopastoral system. In the intensive rotational grazing systems, the control schemes allow to reach a significant reduction in the tick load on cattle considering a time interval from spring to autumn. However, the efficacy levels were not high enough in some specific moments, namely, the tick counts of summer and autumn (there were not significant differences between treated and control groups). The scheme evaluated in the silvopastoral grazing system yielded better results than those tested for the intensive rotational system, because significant differences in tick load between treated and control groups were observed in all post-treatment counts and when the analysis was performed for the whole study period. However, values of efficacy in the count-by-count comparison were disparate, ranging from 64.1 to 99.7. Although the efficacy values obtained in the silvopastoral system were better than those of the rotational grazing systems, the total tick load on treated cattle in autumn was not low enough (mean abundance values 25.14 and 38.14). Ticks were more evenly distributed among hosts in late summer and autumn than in spring or early summer, where few hosts carry most of the ticks. Some management strategies as intensive rotational systems or silvopastoral structures can lead to a more efficient forage use, but they imply greater tick challenge than in extensive grazing systems. In these situations, the schemes of strategic control bases on three or four annual treatments should be complemented with additional tactical treatments in late summer or autumn.

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This study aimed to identify the regions of the body surface of silver catfish (Rhamdia quelen) with a higher population of mucous cells in the skin. Additionally, the effects of stressful conditions, such as different stocking densities and food deprivation, on the proliferative response of mucous cells in the skin and gill epithelium and their impact on cutaneous mucous lysozyme activity were investigated. Silver catfish were divided into four experimental groups: high stocking density (32 kg/m3) and fed (HSD-F), high stocking density and fasted (HSD-FS), low stocking density (2.5 kg/m3) and fed (LSD-F), and low stocking density and fasted (LSD-FS). Fish in the fed groups received commercial feed twice a day, amounting to 1% of the tank biomass. After a 14-day experimental period, the fish were anesthetized and euthanized. Samples of cutaneous mucous and skin fragments from seven different points and the second left branchial arch were collected. Histological slides of the skin and gills were stained with PAS + Alcian Blue at pH 2.5, and the epidermal mucous lysozyme activity was assessed using the turbidimetric method. The ventral point in front of the ventral fin was found to be the optimal location for collecting cutaneous epithelia due to its higher density of mucous cells. The population of mucous cells in both the skin and gills varied based on the collection point and treatment applied. The highest lysozyme activity in the epidermal mucous was observed in fish from the HSD-F group. Overall, these findings suggest that stocking density and food deprivation create stressful conditions for silver catfish, which modulate their mucosal response to each situation.

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Pooled data analysis is an analytical method that combines results from multiple studies. This technique provides a more robust estimate of the effects of an investigation. We performed a database analysis from seventeen experiments developed at Federal University of Santa Maria, Rio Grande do Sul state, Brazil, between 1999 and 2017 to characterize individual performance per area and stocking rate with or without supplementation of replacement heifers grazing winter pastures. Data were separated into two groups: with and without energy supplement provision, and into five subgroups based on supplement levels. Heifers from both groups were maintained under similar forage biomass and leaf blade allowance. Statistical analyses were run on R software using a 'meta' package. Supplement supply increased average daily gain and gain of body condition scores by 11.1% and 20.0%, respectively. Supplement levels higher than 1.2% of body weight resulted in higher weight gain per area, with the stocking rate increasing with higher supplement levels.

Análise conjunta de dados é um método analítico que integra os resultados de muitos estudos. Essa técnica fornece uma estimativa mais robusta sobre os efeitos de uma investigação. Com o objetivo de caracterizar o desempenho individual, por área e a taxa de lotação com uso ou não de suplementos para novilhas de reposição mantidas em pastagem de inverno, foi realizada uma análise de banco de dados de dezessete experimentos conduzidos na Universidade Federal de Santa Maria (UFSM), RS, Brasil, entre 1999 e 2017. Os dados foram estratificados em dois grupos: com e sem suplemento energético e cinco subgrupos de acordo com o nível de suplemento. As novilhas de ambos os grupos foram mantidas em similar massa de forragem e oferta de lâminas foliares. As análises estatísticas foram executadas no software R, pacote 'meta'. O fornecimento de suplemento aumentou o ganho médio diário em 11.1% e em 20.0% o ganho no escore de condição corporal. Níveis de fornecimento maiores que 1.2% do peso corporal proporcionaram o maior ganho de peso por área e a taxa de lotação aumenta à medida que os níveis de suplemento aumentam.

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The objective was to evaluate whether space allowance during pre-slaughter transport of European breeding quail affects welfare, carcass traits and meat quality. A total of 248 quails (body weight = 344.90 ± 2.09 g) were used. During pre-transport, the quails were fasted for 5 hours and 30 minutes. The poultry were caught and placed in plastic transport crates with an area of 0.40 m2. The treatments consisted of a different space allowance in each crate: 22, 28, 34 or 40 quails per crate. Immediately upon arrival at the slaughterhouse, the quails were stunned. During bleeding, blood samples were collected. The carcasses were individually weighed. The meat quality was measured. Data were analysed using the effects of space allowance during transport of quails and pickup truck as dependent variables. Death on arrival increased as the space allowance in transport crates decreased (p=0.08). Glucose and uric acid levels were not significantly different between groups (p≥0.14). The cold carcass weight presented the maximum value when the crates contained 31 quails (p=0.03). The meat pH, intensity of red, intensity of yellow and cooking losses were not different between groups (p≥0.12). The meat lightness value presented the maximum value when the crates contained 31 quails (p=0.04). In view of the above, the number of European breeding quails transported in crates must not exceed 30 animals.(AU)

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The effects of outdoor access, stocking density, and age on broiler behavior, stress, and health indicators in a tropical climate were assessed over two seasons, winter and summer. Two hundred and forty Cobb500 male chickens were allocated to one of four treatments, with six replicates of ten birds in each: low stocking density indoors with outdoor access (LO); high stocking density indoors with outdoor access (HO); low stocking density indoors without outdoor access (LI); and high stocking density indoors without outdoor access (HI). Scan sampling was used to record their behavior both indoors and outdoors. At 28 and 42 days old, blood samples were obtained to determine the heterophil to lymphocyte (H/L) ratio. At 42 days old, chickens were culled and inspected for footpad dermatitis (FPD), and bone quality was examined. Their spleens and bursas of Fabricius were collected and weighed, relative to carcass weight (RW). A factorial analysis was used to test the effects of season (winter or summer), outdoor access (with or without), stocking density (low: 5 animals/m2 or high: 10 animals/m2), and age (28 or 42 days) on the behavior and stress and health indicators. There were no major effects of providing outdoor access on behavior, except that resting was reduced by providing outdoor access to older birds and those at low stocking densities inside. Resting was also greater in indoor and high-density treatments during winter. The bursa of Fabricius was heavier in summer in outdoor birds. The tibia bones were shorter in the outdoor birds. Heterophil numbers were greater in the outdoor treatments in summer but not in winter. These results indicate that outdoor access can increase activity in some situations, and potentially increase bone strength, but it may also increase the risk of stress, particularly heat stress in summer.

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Introducción: las úlceras vasculares son lesiones que se desarrollan principalmente en miembros inferiores, se acompañan de dolor continuo e incapacitante, dificultan la movilidad, alteran la propia imagen corporal y pueden interferir en las actividades de la vida diaria. Las úlceras venosas son graves, ocasionadas por insuficiencia venosa crónica e hipertensión venosa permanente, y la persona que las padece debe recibir cuidados de enfermería integrales, que contribuyan al autocuidado. Objetivo:describir las estrategias que debe tener en cuenta el profesional de enfermería para la promoción del autocuidado en personas con úlceras vasculares venosas. Metodología: revisión integrativa de la literatura. Se realizó búsqueda en bases de datos y recursos electrónicos: Medline a través de PubMed Health, Epistemonikos y SciELO. Se incluyeron artículos de investigación y de revisión relacionados con el problema en estudio, publicados en inglés, portugués o español en el periodo 2010-2020. Estudio sin riesgo, se respetan los derechos de autor. Resultados: se analizó una muestra constituida por 41 publicaciones. Los temas principales producto del análisis fueron: proceso de atención de enfermería y autocuidado, familiarizándose con la úlcera venosa y las opciones terapéuticas, conocimiento de la terapia de compresión, práctica de los estilos de vida saludables. Conclusiones: el cuidado de enfermería al paciente con úlcera venosa debe comenzar por reconocer a la persona desde una perspectiva holística y en reciprocidad con su entorno, lo que implica un proceso de atención integral que va más allá de la úlcera y valora al paciente como un sujeto activo en el cuidado, para que se familiarice con su herida y esté en capacidad de detectar señales de mejoría o de alarma, así como de conocer la terapia de compresión y opciones terapéuticas y de llevar a su cotidianidad la práctica de estilos de vida saludables

Introduction: Venous ulcers are lesions developed mainly on the lower limbs. They cause continuous and disabling pain, impair mobility, alter self-image, and interfere with daily life activities. Venous ulcers are serious. They are caused by chronic venous insufficiency and permanent venous hypertension. People suffering from venous ulcers should receive comprehensive nursing care that contributes to self-care. Objective: To describe the strategies nursing professionals should consider for promoting self-care in people with venous ulcers. Method: Integrative review of the literature. Databases and electronic resources were searched: Medline using PubMed, Health, Epistemonikos, and SciELO. Research and review articles related to the study problem, published in English, Portuguese, or Spanish between 2010 and 2020, were included. This is a risk-free study, and copyrights were respected. Results: A sample of 41 publications was analyzed. The main themes derived from the analysis were the nursing care process and self-care, getting familiar with venous ulcers and therapeutic options, knowledge of compression therapy, and practice of healthy lifestyles. Conclusions: Nursing care for patients with venous ulcers should begin by recognizing a person from a holistic perspective and reciprocally with their environment. This approach implies a comprehensive care process that goes beyond the ulcer and values patients as active subjects of care so that they become familiar with their wounds and detect signs of improvement or warning. They can also know about compression therapy and therapeutic options and take the practice of healthy lifestyles into their daily lives.

Introdução: As úlceras vasculares são lesões que se desenvolvem principalmente nos membros inferiores, são acompanhadas de dor contínua e incapacitante, dificultam a mobilidade, alteram a própria imagem corporal e podem interferir nas atividades da vida diária. As úlceras venosas são graves, causadas pela insuficiência venosa crônica e hipertensão venosa permanente, e a pessoa que as sofre deve receber cuidado de enfermagem integral que contribua para o autocuidado. Objetivo: Descrever as estratégias que o profissional de enfermagem deve levar em consideração para promover o autocuidado em pessoas com úlceras vasculares venosas. Metodologia: Revisão integrativa da literatura. Realizou-se busca nas bases de dados e recursos eletrônicos: Medline por meio do PubMed Health, Epistemonikos SciELO. Foram incluídos artigos de pesquisa e revisão relacionados ao problema em estudo, publicados em inglês, português ou espanhol, no período 2010-2020. Estudo sem risco, os direitos autorais são respeitados. Resultados: Foi analisada uma amostra de 41 publicações. Os principais tópicos resultantes da análise foram: processo de atenção de enfermagem e autocuidado, familiarização com a úlcera venosa e as opções terapêuticas, conhecimento da terapia compressiva, prática de estilos de vida saudáveis. Conclusões: O cuidado de enfermagem ao paciente com úlcera venosa deve começar por reconhecer à pessoa desde uma perspectiva holística e em reciprocidade com seu meio, o que implica um processo de atendimento integral que vai além da úlcera e valoriza ao paciente como sujeito ativo no cuidado para que ele se familiarize com sua ferida e seja capaz de detectar sinais de melhora ou alarme, bem como aprender sobre terapia compressiva e as opções terapêuticas e praticar estilos de vida saudáveis em sua vida diária.

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The wet-dry transition period brings unique challenges to cattle producers in the tropics as the forage quality starts to decrease and animal performance is negatively affected unless supplementation strategies are applied. Two experiments were conducted concomitantly to evaluate the performance and metabolic parameters of cattle supplemented with two different energy sources under a C4 tropical grass continuous grazing system in the wet-dry transition period. In experiment (exp) 1, the liveweight (LW) gain of 42 growing Bos indicus Nellore bulls allocated to 12 paddocks of Uruchloa brizantha cv. Marandu, in a completely randomized block design, was evaluated to compare corn and citrus pulp-based supplements offered at 0.5% LW. Metabolism was evaluated in exp 2 with eight rumen-cannulated Nellore steers in an incomplete replicated Latin square design (RLSD) 4 × 2 (steers × treatment) fed the same two treatments as in exp 1. No differences in animal performance were observed between corn or citrus pulp-based supplements. Rumen pH, ammonia nitrogen, and blood urea nitrogen were lower in the rumen of animals supplemented with citrus pulp. Despite this, there were no differences in total dry matter intake amongst the two energy sources. The neutral detergent fibre digestibility of the diet containing corn decreased, but it neither affected performance nor liveweight gain per area. The findings suggest that corn can be replaced by citrus pulp with neither detrimental effects on animal performance nor indirect effects on pastures productivity.

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Laboratory rodents spend the entire day housed in standard cages that provide a restricted area for movements and might, therefore, limit physical activity. However, it has not been tested in immature rodents of ages ranging from weaning to adulthood (adolescence period) whether the restricted area per animal does actually reduce physical activity and impact the body composition. We analyzed the spontaneous physical activity and feeding behavior during the adolescence of mice kept in two different housing conditions (standard stocking density (SSD) versus low stocking density (LSD)). We aimed to compare the body composition between SSD and LSD groups before they reached adulthood. Differential housing began at four weeks of age and was maintained for four weeks until euthanasia at eight weeks of age. The SSD group had a floor space of 88 cm2 available per animal, while LSD mice were housed with a floor space of 320 cm2 per animal, increasing the individual radius for movement more than three-fold compared with standard requirements. Mice kept in SSD exhibit lower spontaneous physical activity than mice kept in LSD. Early-life exposure to reduced physical activity in mice housed in SSD resulted in greater visceral fat accumulation before adulthood. An environment enabling/stimulating physical activity should be established for rodents as early as possible. This study will be helpful in showing that mice kept in SSD are early exposed to a reduced physical activity already in the adolescence period. Our findings could raise reflections about the translatability of rodents kept in SSD to healthy active humans.

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1. The study was carried out to evaluate the effect of stocking density on performance, litter moisture, Eimeria oocyst shedding, intestinal and foot lesions in broilers.2. A total of 192 1-d-old male Cobb broilers were distributed with three different stocking densities (6, 8 or 10 chickens/m2) with outdoor access and eight replicates in a completely randomised design over two periods. Productive parameters were measured from 3 to 7 weeks of age.3. Oocyst counts (OPG) in both excreta and litter were performed at 3, 4 and 5 weeks of age. Intestinal and foot pad lesions were evaluated at 7 weeks old. The stocking density of 6 birds/m2 had the highest body weights (P < 0.05) (2129 ± 37.67, 2759 ± 50.82 and 3167 ± 75.64 g at weeks 5, 6 and 7 of age, respectively).4. Feed intake decreased with increasing stocking density at week 3 (r = -0.57), 4 (r = -0.48), 5 (r = -0.84), 6 (r = -0.68) and 7 (r = -0.65) of age (P < 0.05). Birds with stocking densities of 8 and 10/m2 consumed, respectively, up to 11% and 19.5% less feed than the lower stocking density groups.5. Stocking density affected (P < 0.05) feed conversion (1.61, 1.49 and 1.46) and litter moisture (40.88, 52.60 and 56.19%) at 3 weeks of age. Neither carcase yield nor mortality was different between densities (P > 0.05). Likewise, there was no effect of stocking density on OPG neither in excreta nor in litter, intestinal lesions, or foot pad and hock injuries (P > 0.05).6. In conclusion, the higher stocking density decreased both the feed intake and the live weight in broilers, but there were no effects in the number of Eimeria OPG in excreta or litter, neither intestinal lesions nor in foot pad injuries.

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This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.(AU)

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This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.

This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.

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This study aimed to evaluate the morphogenic and structural characteristics and the population stability index of ryegrass (Lolium multiflorum Lam.) tillers when the pasture was submitted to two stocking methods during grazing cycles. The experimental design was a complete randomized block, with repeated measurements over time (n=6 cycles), two treatments (stocking methods) and three area replicates. In the continuous stocking method, the highest population density of tillers was observed. The highest tiller weight occurred in the rotational stocking method. The morphogenic variables and the other structural variables were not altered by the stocking methods and showed differences during the grazing cycles. The tiller population stability index was similar in the two pasture management strategies, and both can be used for ryegrass management considering this parameter.

Este estudo teve como objetivo avaliar as características morfogênicas, estruturais e o índice de estabilidade populacional de perfilhos do azevém (Lolium multiflorum Lam.) quando a pastagem foi submetida a dois métodos de lotação, durante ciclos de pastejo. O delineamento experimental foi em blocos completos casualizados, com medidas repetidas ao longo do tempo (n = 6 ciclos), dois tratamentos (métodos de lotação) e três repetições de área. No método de lotação contínua, foi observada a maior densidade populacional de perfilhos. O maior peso de perfilhos ocorreu no método de lotação rotativa. As variáveis morfogênicas e as demais variáveis estruturais não foram alteradas pelos métodos de lotação e apresentaram diferenças durante os ciclos de pastejo. O índice de estabilidade populacional de perfilhos foi semelhante nas duas estratégias de manejo do pasto e ambas podem ser utilizadas para o manejo do azevém considerando-se esse parâmetro.

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La arena para aviarios se utiliza para absorber la humedad y convertirse en una barrera para el contacto directo del ave con el suelo en los sistemas de cría intensiva. De esta forma, contribuye al bienestar y mejor desempeño productivo de las aves al reducir los cambios bruscos de temperatura en los galpones. El objetivo de este trabajo fue evaluar las características físicas y químicas de cuatro tipos de material de cama bajo dos densidades de alojamiento y el comportamiento de pollos de engorde alojados en diferentes tratamientos durante un período de 42 días. Se adoptó un diseño experimental completamente al azar, en un esquema factorial 4 x 2 (cuatro tipos de material de cama y dos tasas de carga) y cinco repeticiones. Los cuatro tipos de material de cama fueron arena lavada, virutas de madera, cáscara de arroz y heno Tifton 85 y las dos tasas de carga fueron de 10 y 14 aves/m2. Los parámetros de desempeño de los animales evaluados fueron: aumento de peso, consumo, conversión alimenticia, peso vivo y viabilidad, mientras que las características analizadas de la camada fueron: pH, temperatura y humedad. Los materiales utilizados para la cama de aves de corral no afectaron negativamente el rendimiento de las aves, sin embargo, las aves alojadas a una densidad de 10 aves/m2 tuvieron un mejor rendimiento. No hubo diferencia entre los valores de pH y temperatura de los diferent

Aviary litter is used to absorb moisture and become a barrier to the bird's direct contact with the ground in intensive rearing systems. In this way, it contributes to the welfare and better productive performance of birds by reducing sudden temperature changes in the sheds. The objective of this work was to evaluate the physical and chemical characteristics of four types of litter material under two housing densities and the performance of broilers housed in different treatments over a period of 42 days. A completely randomized experimental design was adopted, in a 4 x 2 factorial scheme (four types of litter material and two stocking rates) and five replications. The four types of litter material were washed sand, wood shavings, rice husk and Tifton 85 hay and the two stocking rates were 10 and 14 birds/m2. The performance parameters of the evaluated animals were: weight gain, consumption, feed conversion, live weight and viability, while the analyzed characteristics of the litter were: pH, temperature and humidity. The used poultry litter materials did not negatively affect the performance of the birds, however the birds housed at a density of 10 birds/m2 had better performance. There was no difference between the pH and temperature values of the different treatments, however the humidity of the sand bed at a density of 10 birds/m2 was significantly higher than that of the o

A cama de aviário é utilizada para absorver umidade e se tornar uma barreira do contato direto da ave com o chão em sistemas intensivos de criação. Desse modo, contribui para o bem-estar e melhor desempenho produtivo das aves por reduzir as mudanças bruscas de temperatura nos galpões. O objetivo deste trabalho foi avaliar as características físico-químicas de quatro tipos de material de cama aviária sob duas densidades de alojamento e o desempenho de frangos de corte alojados nos diferentes tratamentos no período de 42 dias. Foi adotado o delineamento experimental inteiramente ao acaso, em um esquema fatorial 4 x 2 (quatro tipos de material de cama e duas taxas de lotação) e cinco repetições. Os quatro tipos de material de cama foram areia lavada, maravalha, casca de arroz e feno de Tifton 85 e as duas taxas de lotação foram 10 e 14 aves/m2. Os parâmetros de desempenho dos animais avaliados foram: ganho de peso, consumo, conversão alimentar, peso vivo e viabilidade, enquanto que as características analisadas da cama foram: pH, temperatura e umidade. Os materiais de cama aviária utilizados não afetaram negativamente o desempenho das aves, entretanto as aves alojadas na densidade de 10 aves/m2 apresentam melhor desempenho. Não houve diferença entre os valores de pH e temperatura dos diferentes tratamentos, entretanto a umidade da cama de areia na densidade de 10 aves/m2 foi signi

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A cama de aviário é utilizada para absorver umidade e se tornar uma barreira do contato direto da ave com o chão em sistemas intensivos de criação. Desse modo, contribui para o bem-estar e melhor desempenho produtivo das aves por reduzir as mudanças bruscas de temperatura nos galpões. O objetivo deste trabalho foi avaliar as características fisico-químicas de quatro tipos de material de cama aviária sob duas densidades de alojamento e o desempenho de frangos de corte alojados nos diferentes tratamentos no período de 42 dias. Foi adotado o delineamento experimental inteiramente ao acaso, em um esquema fatorial 4 x 2 (quatro tipos de material de cama e duas taxas de lotação) e cinco repetições. Os quatro tipos de material de cama foram areia lavada, maravalha, casca de arroz e feno de Tifton 85 e as duas taxas de lotação foram 10 e 14 aves/m2. Os parâmetros de desempenho dos animais avaliados foram: ganho de peso, consumo, conversão alimentar, peso vivo e viabilidade, enquanto que as características analisadas da cama foram: pH, temperatura e umidade. Os materiais de cama aviária utilizados não afetaram negativamente o desempenho das aves, entretanto as aves alojadas na densidade de 10 aves/m² apresentam melhor desempenho. Não houve diferença entre os valores de pH e temperatura dos diferentes tratamentos, entretanto a umidade da cama de areia na densidade de 10 aves/m² foi significativamente maior que a dos demais materiais. Portanto, os materiais de cama aviária utilizados nesse estudo apresentaram características físico-químicas semelhantes, sendo que a areia lavada tem maior poder de absorção de água, mas, mesmo assim, não afetou negativamente o desempenho das aves. As aves alojadas na densidade de 10 aves/m² apresentaram melhor desempenho.

Aviary litter is used to absorb moisture and become barrier to the bird's direct contact with the ground in intensive rearing systems. In this way, it contributes to the welfare and better productive performance of birds by reducing sudden temperature changes in the sheds. The objective of this work was to evaluate the physical and chemical characteristics of four types of litter material under two housing densities and the performance of broilers housed in different treatments over a period of 42 days. A completely randomized experimental design was adopted, in a 4 x 2 factorial scheme (four types of litter material and two stocking rates) and five replications. The four types of litter material were washed sand, wood shavings, rice husk and Tifton 85 hay and the two stocking rates were 10 and 14 birds/m². The performance parameters of the evaluated animals were: weight gain, consumption, feed conversion, live weight and viability, while the analyzed characteristics of the litter were: pH, temperature and humidity. The used poultry litter materials did not negatively affect the performance of the birds, however the birds housed at a density of 10 birds/m² had better performance. There was no difference between the pH and temperature values of the different treatments, however the humidity of the sand bed at a density of 10 birds/m² was significantly higher than that of the other materials. Therefore, the avian litter materials used in this study had similar physicochemical characteristics, with washed sand having greater water absorption power, but even so, it did not negatively affect the performance of the birds. Poultry housed at a density of 10 birds/m2 showed better performance.

La arena para aviarios se utiliza para absorber la humedad y convertirse en una barrera para el contacto directo del ave con el suelo en los sistemas de cría intensiva. De esta forma, contribuye al bienestar y mejor desempeño productivo de las aves al reducir los cambios bruscos de temperatura en los galpones. El objetivo de este trabajo fue evaluar las características físicas y químicas de cuatro tipos de material de cama bajo dos densidades de alojamiento y el comportamiento de pollos de engorde alojados en diferentes tratamientos durante un período de 42 días. Se adoptó un diseño experimental completamente al azar, en un esquema factorial 4 x 2 (cuatro tipos de material de cama y dos tasas de carga) y cinco repeticiones. Los cuatro tipos de material de cama fueron arena lavada, virutas de madera, cáscara de arroz y heno Tifton 85 y las dos tasas de carga fueron de 10 y 14 aves/m². Los parámetros de desempeño de los animales evaluados fueron: aumento de peso, consumo, conversión alimenticia, peso vivo y viabilidad, mientras que las características analizadas de la camada fueron: pH, temperatura y humedad. Los materiales utilizados para la cama de aves de corral no afectaron negativamente el rendimiento de las aves, sin embargo, las aves alojadas a una densidad de 10 aves/m² tuvieron un mejor rendimiento. No hubo diferencia entre los valores de pH y temperatura de los diferentes tratamientos, sin embargo la humedad del lecho de arena a una densidad de 10 aves/m² fue significativamente mayor que la de los otros materiales. Por lo tanto, los materiales de cama de aves utilizados en este estudio tenían características fisicoquímicas similares, teniendo la arena lavada un mayor poder de absorción de agua, pero aun así, no afectó negativamente el desempeño de las aves. Las aves de corral alojadas a una densidad de 10 aves/m² mostraron un mejor rendimiento.

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This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3x3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry,and end of dry season), with repeated measuresover time. The following variables were evaluated: canopyheight, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitrodry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore),was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction amongcultivarsand period of the year the similarity in animal performance amongthe cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.(AU)

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This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.

This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.

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RESUMEN La región de la Orinoquia, se caracteriza por poseer espejos de agua que se mantienen durante todo el año, aportando peces para consumo local. La pesca artesanal constituye la principal actividad económica de sustento de comunidades ribereñas, quienes están siendo amenazadas en su seguridad alimentaria, por la disminución del recurso íctico, debido a múltiples causas atribuidas a la actividad humana. Por lo anterior, sistemas de producción en jaulas flotantes, elaboradas con materiales de bajo costo y ubicadas en cursos de aguas naturales, constituyen una alternativa económica para estas comunidades. El objetivo fue evaluar el rendimiento productivo de la cachama blanca en jaulas flotantes, ubicadas en el río Manacacias, manejando tres densidades: 150, 200 y 250 peces/m3. Se sembraron alevinos en jaulas, con dimensiones de 10,2 m³ (3 x 2 x 1,7 m). Los peces fueron alimentados con alimento balanceado, durante 126 días. Al final del experimento, los individuos fueron cosechados. Se produjo una biomasa promedio por densidad de 47,42 kg/m3, en la densidad 150; 45,11 kg/m3, en 200 peces/m3 y 79,65 kg/m3, en la densidad 250. Su conversión alimenticia fue 1,1; 1,32 y 0,8, la sobrevivencia de 83,51, 78,98 y 93,72 %, respectivamente. Se concluye, que la cachama blanca puede ser cultivada en jaulas flotantes a altas densidades, obteniendo parámetros productivos óptimos y, adicionalmente, puede ser una fuente de ingresos significativa para las comunidades.

ABSTRACT The Orinoquia region is characterized by having water bodies that are maintained throughout the year, providing fish for local consumption. Artisanal fishing constitutes the main economic activity for the livelihood of riverine communities, which are being threatened in their food security by the decrease in the fish resource due to multiple causes attributed to human activity. Therefore, production systems in floating cages, made with low-cost materials and located in natural water courses, constitute an economic alternative for these communities. The objective of this work was to evaluate the productive performance of white cachama in floating cages located in the Manacacias river, managing three densities 150, 200 and 250 fish/m3. Fingerlings were sown in cages with dimensions of 10.2 m³ (3 x 2 x 1.7 m). The fish were fed with balanced feed for 126 days. At the end of the experiment the individuals were harvested in three cages for the three densities. An average biomass by density of 47.22 kg/m3 was produced at density 45.11 kg/m3 in 200 fish/m3 and 79.65 kg/m3 at density 250. Its feed conversion was 1.1, 1.32 and 0.8, the survival of 83.51, 78.98 and 93.72 % respectively. It is concluded that cachama blanca can be cultivated in floating cages at high densities, obtaining optimal productive parameters and additionally, it can be a significant source of income for the communities.

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Survival and growth of the native oyster Crassostrea gasar along the juvenile and adult phases were evaluated in three different stocking densities [low (D), medium (2D) and high (3D)] and in two grow-out systems (fixed and floating system). The fixed system consisted of a rack made with PVC, fixed from the bottom with wood sticks. The floating system consisted of floating bags suspended by a rack made with PVC and maintained submerged from the seawater surface by eight floats. Survival and shell height of oysters cultured after 30, 60 and 90 days were registered in each phase and in each grow-out system. Results showed that the grow-out system did not affect survival and growth of C. gasar in the juvenile and adult phases. The tested densities affected the survival of oysters cultured over time in both phases but did not affect oyster growth. At times analyzed, it was observed positive growth in juvenile oysters grow after 90 days of culture. However, in the adult phase, no growth was observed after 90 days of culture. Oyster yield was higher in the density 3D, in both juvenile and adult phases. These findings contributed to the development of the oyster C. gasar culture.(AU)

A sobrevivência e o crescimento da ostra nativa Crassostrea gasar nas fases juvenil e adulta foram avaliados sob três diferentes densidades de estocagem [baixa (D), média (2D) e alta (3D)] e dois sistemas de engorda (fixo e flutuante). O sistema fixo consistiu em uma mesa de PVC, fixada na parte inferior com varas de madeira. O sistema flutuante consistiu em travesseiros flutuantes suspensos por uma mesa de PVC e mantidas submersas da superfície da água do mar por oito flutuadores. Registraram-se sobrevivência e altura da concha de ostras cultivadas após 30, 60 e 90 dias, em cada fase (juvenil e adulta) e em cada sistema (fixo e flutuante). Os resultados mostraram que o sistema de engorda não afetou a sobrevivência e o crescimento de C. gasar nas fases juvenil e adulta. As densidades testadas afetaram a sobrevivência das ostras ao longo do tempo, em ambas as fases, mas não afetaram o crescimento em altura. Nos tempos analisados, ostras juvenis apresentaram crescimento após 90 dias de cultivo. Porém, na fase adulta, não foi observado crescimento após 90 dias de cultivo. A produção de ostras, foi maior na densidade 3D, nas fases juvenil e adulta. Os presentes achados contribuíram para o desenvolvimento do cultivo da ostra C. gasar.(AU)

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One of the main production challenges associated with climate change is the reduction of carbon emissions. Increasing the efficiency of resource utilization is one way to achieve this purpose. The modification of production systems through improved reproductive, genetic, feed, and grazing management practices has been proposed to increase technical-economic efficiency, even though the "environmental viability" of these modifications has not always been evaluated. The objective of this study was to evaluate the use of feeding and management strategies on the carbon footprint (CF) and economic variables in the traditional cow-calf system in southern Chile using a simulation model. The modifications evaluated corresponded to combinations of stocking rate, use of creep feeding practices with different supplementation levels, and the incorporation of feed additives to the supplement, using factorial experiments. Additionally, the scenarios were evaluated with and without carbon sequestration. The CF for the baseline scenarios was 12.5 ± 0.3 kg of CO2-eq/kg of live weight (LW) when carbon sequestration was considered and 13.0 ± 0.4 kg of CO2-eq/kg of LW in the opposite case. Changes in stocking rate, supplementation level, and consideration of carbon sequestration in pasture and soil had a significant effect on the CF in all simulated scenarios. The inclusion of additives in the supplement did not have a significant effect on production costs. With regard to reducing greenhouse gas (GHG) emissions, incorporating canola oil presented the best average results. The model developed made the selection of environmentally viable feed strategies or management adaptations possible.