Forage Supplementation Feeding of Lactating Merino Ewes in Dry Season at the Foothills Agro-ecological Zone in Lesotho

A farmer-participatory research, which lasted for seven weeks, was carried out at Machache, in the Foothills Agro-Ecological Zone of Lesotho to examine the effect of forage based diets supplementary feeding on the performance response and milk quality of lactating ewes during dry lambing season. A total of 270 lactating merino ewes were randomly distributed among four dietary treatments: basal diet (T1) which was the range land pasture used as control, cereal forage based diet (T2), leguminous forage based diet (T3) and mixed forage based diet (T4). The feed value of the supplementary diets T2 (4.70% CP and 9.94MJ/kg ME), T3 (12.31% CP and 10.27 MJ/kg ME), T4 (11.90% CP and 10.47 MJ/kg ME)] was superior to that of the range land pasture T1 (2.80% CP and 8.61MJ/kg ME). Ewes on forage supplemented diets performed significantly (P<0.05) better than the control group in feed intake, live body weight and live weight change. The milk quality evaluation showed that solids-non-fat (SNF), protein and lactose were highly significant (P<0.05) for T3 and T4 than T1 and T2 which had high milk fat. The study revealed that diets T1 and T2 lacked the nutritional capacity to meet the nutrient requirements of lactating ewes as evidenced by slight body weight improvement. It is concluded that supplementary diets T3 (leguminous forage based diet) and T4 (mixed forage based diet) contained adequate nutrients that can meet the requirement of lactating ewes during dry lambing season. This was verified by high voluntary feed intake and good nutrients utilization as resulted by improving of body weight and high milk quality response of lactating ewes.

Survey of total radioactivity in drinking well water around Bayanwula uranium mine / 中华放射医学与防护杂志

Objective:To investigate the total radioactivity in drinking well water around the Bayanwula uranium mine.Methods:Totally 174 samples of drinking well water and 5 samples of filtered well water from residential houses were collected during dry and wet seasons in 2020 around the Bayanwula uranium mine. Total α and total β radioactivity in dry season and wet season were analyzed for detrmining whether there were differences between them and the relation between total radioactivity with different locations away from the uranium center. The radioactivity in filtered drinking well water used in residential houses was also investigated. Radioactivity were measured and analyzed using low background alpha and beta radioactivity meters, and the data were analysed using SPSS analytical statistical method.Results:In the drinking well water around Bayanwula uranium mine, the activity concentrations of total α and β measured in dry season were 0.024-2.468 Bq/L with a mean of (0.605±0.507) Bq/L and 0.125-1.395 Bq/L with a mean of (0.420±0.235) Bq/L, respectively. The values measured in wet season were 0.049-2.988 Bq/L with a mean of (0.825±0.605) Bq/L for total α and 0.059-1.623 Bq/L with a mean of (0.506±0.265) Bq/L for total β, respectively. The average value of total radioactivity in water samples was lower within 10, 30 and 20 km of the uranium mine in the descending order.Conclusions:The radioactivity in well water around the Bayanwula uranium mine is high, with the total α and β in samples greater in wet season than in the dry season and without elevated levels as compared to the pre-mining background.

Principal component regression analysis demonstrates the collinearity-free effect of sub estimated climatic variables on tree growth in the central Amazon / El análisis de regresión por componentes principales muestra el efecto libre de colinealidad de variables climáticas subestimadas sobre el crecimiento de los árboles en la Amazonía central

Abstract Introduction: Climatic variables show a seasonal pattern in the central Amazon, but the intra-annual variability effect on tree growth is still unclear. For variables such as relative humidity (RH) and air vapor pressure deficit (VPD), whose individual effects on tree growth can be underestimated, we hypothesize that such influences can be detected by removing the effect of collinearity between regressors. Objective: This study aimed to determine the collinearity-free effect of climatic variability on tree growth in the central Amazon. Methods: Monthly radial growth was measured in 325 trees from January 2013 to December 2017. Irradiance, air temperature, rainfall, RH, and VPD data were also recorded. Principal Component Regression was used to assess the effect of micrometeorological variability on tree growth over time. For comparison, standard Multiple Linear Regression (MLR) was also used for data analysis. Results: Tree growth increased with increasing rainfall and relative humidity, but it decreased with rising maximum VPD, irradiance, and maximum temperature. Therefore, trees grew more slowly during the dry season, when irradiance, temperature and VPD were higher. Micrometeorological variability did not affect tree growth when MLR was applied. These findings indicate that ignoring the correlation between climatic variables can lead to imprecise results. Conclusions: A novelty of this study is to demonstrate the orthogonal effect of maximum VPD and minimum relative humidity on tree growth.

Resumen Introducción: Las variables climáticas muestran un patrón estacional en la Amazonía central, pero el efecto de la variabilidad intra-anual en el crecimiento de los árboles aún no está claro. Para variables como la humedad relativa (HR) y el déficit de presión de vapor (VPD), cuyo efecto individual en el crecimiento de los árboles puede ser subestimada, planteamos la hipótesis de que tales influencias pueden detectarse eliminando el efecto de colinealidad entre regresores. Objetivo: Este estudio tuvo como objetivo determinar el efecto libre de colinealidad de la variabilidad climática sobre el crecimiento de los árboles en la Amazonía central. Métodos: Se midió el crecimiento radial mensual en 325 árboles desde enero 2013 hasta diciembre 2017. También se registraron datos de irradiancia (PAR), temperatura del aire, lluvia, humedad relativa (RH) y déficit de presión de vapor de aire (VPD). Se utilizó la regresión de componentes principales para evaluar el efecto de la variabilidad micrometeorológica a lo largo del tiempo sobre el crecimiento de los árboles. Para comparación, también se utilizó la regresión lineal múltiple (MLR) estándar para el análisis de datos. Resultados: El crecimiento de los árboles incrementó con el aumento de las precipitaciones y la humedad relativa, y disminuyó con el aumento de la VPD máxima, la irradiancia y la temperatura máxima. Por lo tanto, los árboles crecieron más lentamente durante la estación seca, cuando la irradiancia, la temperatura y la VPD eran más altas. La variabilidad micrometeorológica no afectó el crecimiento de los árboles cuando se aplicó MLR. Estos hallazgos indican que ignorar la correlación entre las variables climáticas puede conducir a resultados imprecisos. Conclusiones: Una novedad de este estudio es demostrar el efecto ortogonal del VPD máximo y la humedad relativa mínima sobre el crecimiento de los árboles.

Climate Change, Pollution, Tropical Season, Hiv-Positive, Hiv-Negative And High Frequency Of Hypovitaminosis D In Patients From Kinshasa, Drc

Background: The main source of vitamin D from the human skin and synthetized by violets B rays emitted by the sun. Environmental factors such us season, climate change, diets, and pollution, are therefore likely to inuence the levels on vitamin D. Furthermore, High frequency of vitamin D deciency is now observed among HIV-infected patients. There is no published data about HIV and Vitamin D despite few scientic articles on HIV and vitamin D status reported by other African countries.Objective:This study sought to determine specically increased prevalence of vitamin D deciency and environmental factors associated with HIV-positive compared to HIV-negative.Methods:Patients followed in Kinshasa hospitals, DRC, where evaluated between the October 2015 and November 2017 period. Serum levels of vitamin D were measured in adult HIV-positives and HIV-negatives during the dry season and the rainy season in the context of climate change and pollution of the megacity of Kinshasa. Results:Five hundred and six patients were enrolled. The prevalence of moderate (≤29 and≥20 ng/mL) and severe (<20 ng/mL) 25-OH vitamin D deciency was12% (n=64) and 54,6% (n=273) respectively, 34,4 %had normal status. 62,4% (n=316) and 4,2% (n= 21) of patients with deciency (<30 ng/ml) 25-OH vitamin D were HIV-positive and HIV-negative respectively. Water pollution, air pollution, dry season, and cold season La Niña we resignicantly associated with 25-OH vitamin D deciency (P<0.0001 and <0,05, respectively). Conclusion:Overall, vitamin D deciency was very high whereas vitamin D deciency was epidemic among HIV-positives in comparison with HIV-negatives. Dry season and La Niña season /climate change-variability related to ultraviolet light and oxidative stress-ecotoxicity related pollution might be considered in the prevention and the treatment of HIV-infection in Kinshasa, DRC, Central Africa.

¿Refleja Formicidae el impacto de la degradación de los bosques ribereños en la Amazonía Oriental?

La creciente presión antropogénica sobre la Amazonia Oriental hace imperativo el diagnóstico de la degradación forestal y, particularmente, su efecto sobre las comunidades clave dentro de los ecosistemas ribereños, unos de los últimos bosques amazónicos remantes en el estado de Maranhão. La familia de hormigas Formicidae juega un papel fundamental en el suelo, refleja los cambios en el uso de la tierra y es un grupo abundante en los bosques estudiados. Este trabajo tuvo como objetivo determinar el efecto del gradiente sucesional en la riqueza, frecuencia y composición de esta familia. El muestreo fue realizado durante los periodos seco y lluvioso con el método TSBF. Los organismos recolectados se identificaron a nivel de morfoespecies y se crearon curvas de acumulación de especies. Fueron utilizados modelos lineales mixtos para evaluar los efectos del periodo de recolecta local y estado de sucesión en la riqueza y la frecuencia de las hormigas. Por otro lado, se utilizaron regresiones polinómicas para investigar la relación entre la riqueza y la frecuencia de los formícidos según la cobertura del dosel y la altura de la vegetación. La composición de especies fue representada a través del índice de similitud de Jaccard. En total, 1 940 individuos fueron separados en 86 morfoespecies. Se obtuvo más del 80 % de la riqueza de especies probables. La frecuencia y riqueza de hormigas aumentó significativamente siguiendo la sucesión con valores bajos en las áreas abiertas durante la estación seca. Asimismo, durante esta estación, la cobertura del dosel y la altura de la vegetación tuvieron un efecto parcial en la riqueza y frecuencia de Formicidae. Por su parte, las áreas de sucesión intermedia y avanzada presentaron una composición similar con 50 especies compartidas, seguidas de las áreas de sucesión temprana con 43 y el uso antrópico con 34. Concluimos que la eliminación de los bosques ribereños tiene un efecto considerable sobre la riqueza y frecuencia de Formicidae, con valores mínimos en áreas degradadas durante la estación seca. Por otro lado, las áreas de bosques transformadas en sistemas agrícolas sufrieron pérdidas de 41 y 56% en la riqueza y frecuencia respectivamente. Con la sucesión, se restauran la estructura y las funciones del bosque favoreciendo la recolonización de las especies de hormigas. Finalmente, estos himenópteros son un grupo clave en los programas de monitoreo para la conservación/restauración de los bosques ribereños locales.

The increasing anthropogenic pressure on Eastern Amazon makes imperative the diagnosis of forest degradation, particularly the effect on key communities within the riparian ecosystems, one of the last remaining Amazonian forests in Maranhão State. The ant family Formicidae is an abundant group in these types of forests plays a fundamental role on the soil and also reflects the land use changes. Therefore, this study aimed to determine the impact of riparian forest successional stages on the Formicidae richness, frequency, and composition. Sampling was performed during both dry and wet seasons using the TSBF method. Collected organisms were identified as morphospecies. Also, species-accumulation curves were created. Linear mixed models were used to evaluate the effects of seasonal, local, and successional stage on ant richness and frequency. Polynomial regression models were applied to investigate the relationship between ant richness and frequency with canopy cover and vegetation height. Lastly, the species composition was represented by the Jaccard similarity index. In total, we observed 1 940 individuals grouped into 86 morphospecies. We obtained more than 80 % of the probable species richness. Ant frequency and richness increased significantly, following the successional stage, with low values in the open areas, especially during the dry season. Canopy cover and vegetation height seemed to affect partially both Formicidae richness and frequency during the dry season. Intermediate and advanced successional areas presented similar composition (50) shared species, followed by the areas of early succession (43) and anthropic use (34). We concluded that the elimination of riparian forests produces a considerable effect on the richness and frequency of the Formicidae family, minimally affecting them in open areas during the dry season, but resulting in losses of 41 % in richness and 56 % in frequency in forest areas when they are transformed into agricultural systems. Nevertheless, succession restores forest structure and functions, thus favoring re-colonization of ant species. Formicidae reflects forest degradation and is a key group in monitoring programs for the conservation/restoration of local riparian forests.

Behavioral aspects of Santa Inês sheep kept in pasture in a tropical rainforest climate / Aspectos comportamentais de ovinos da raça Santa Inês mantidos em pasto em clima tropical úmido

ABSTRACT: This study aimed to evaluate behavioral aspects of Santa Inês sheep in pasture in humid tropical climate. In order to do so, nine Santa Inês sheep were kept on pasture, exposed to the climate directly, without shade, for 24 days, with 12 alternate days in each period (dry and raining) in 2015. The behavioral parameters evaluated were: food consumption, standing idleness, lying idle and rumination. Observations occurred from 08:00 A.M. to 05:55 P.M. The experimental was a completely randomized design (CRD) with two treatments (rainy season and dry period), nine replications, one animal per experimental unit. To understand the correlations of the behavioral parameters with the climatic variables, Pearson's correlation was performed. Approximate average values between the rainy and dry periods for the behavioral variables were observed, but there was a greater intake in the volume of water in the dry period (9.59L/sheep). Also, there were significant differences in the behavior of the animals throughout the day. In the hottest time of the day, at 02:00 P.M., there was standing idle of 25.83min., lying idle of 1.21min., and spent less time-consuming food (27.08min.) in relation to other schedules. We concluded that the sheep had similar behavioral parameters in the rainy and dry periods, but when we observe the times of the days, the behaviors are different. The main activity recorded was grazing, and the variables, temperature and relative humidity of the air influence differently between the seasons, being more marked in the dry period.

RESUMO: Este estudo objetivou avaliar aspectos comportamentais de ovinos Santa Inês criados em pasto em clima tropical úmido. Para tanto, foram utilizados nove carneiros Santa Inês, mantidos a pasto, expostos diretamente ao clima, sem sombra, durante 24 dias, sendo 12 dias alternados em cada período (seco e chuvoso) em 2015. Os parâmetros comportamentais avaliados foram consumo de alimento, ócio em pé, ócio deitado e ruminação. As observações ocorreram das 08:00h às 17h:55min. O delineamento experimental foi o inteiramente casualizado (DIC) com dois tratamentos (período chuvoso e período seco), nove repetições, um animal por unidade experimental. Para entender as correlações dos parâmetros comportamentais com as variáveis climáticas foi realizada a correlação de Pearson. Foram observados valores médios gerais aproximados entre os períodos chuvoso e seco para as variáveis comportamentais, porém, houve maior ingestão no volume de água no período seco (9,59L/ovino). Também, ocorreu diferença no comportamento dos animais ao longo do dia. No horário mais quente do dia, das 14h às 15h, registrou-se ócio em pé de 25,83min. e ócio deitado de 1,21min., e os animais passaram menor tempo consumindo alimento (27,08min.) em relação aos demais horários. Podemos concluir que os ovinos apresentaram parâmetros comportamentais semelhantes nos períodos chuvoso e seco, porém, quando observamos os horários dos dias, os comportamentos são diferentes. A principal atividade registrada foi o pastejo. As variáveis temperatura e a umidade relativa do ar influenciam de forma diferente o comportamento dos ovinos entre as estações do ano, sendo mais marcantes no período seco.

Dinámica del plancton en la primera milla náutica frente a la provincia de El Oro, Ecuador / Plankton dynamics in the first nautical mile of El Oro province, Ecuador

Resumen El Oro incluye diferentes sistemas costeros y estuarinos y es parte del Golfo de Guayaquil. Estas áreas proporcionan diferentes servicios ecosistémicos, pero con el aumento de la población y de las diversas actividades económicas, los recursos naturales locales poco estudiados pueden verse afectados negativamente. Es por ello que esta investigación tuvo como objetivo describir la dinámica del plancton, productividad y ecológica de esta área durante la estación seca de 2012, para lo cual se establecieron 17 estaciones para estudiar la distribución espacial y variación mensual de los nutrientes inorgánicos, temperatura, oxígeno disuelto, salinidad, zona fótica, abundancia y composición del plancton y larvas de peces, con métodos estándar. Se establecieron patrones espaciales y temporales mediante análisis de conglomerados y de ordenamiento multidimensional. Los resultados obtenidos de las variables bióticas y abióticas analizadas determinaron un patrón característico de un ecosistema estuarino productivo, así como también la existencia de áreas específicas asociadas a condiciones naturales y antrópicas, que son: a) interior del Archipiélago de Jambelí y frente a la isla Puná, influenciada por las actividades productivas y la hidrografía del área; b) una zona, conformada por las estaciones ubicadas en el estuario exterior donde la influencia oceánica es evidente y c) el canal de Jambelí, caracterizado por procesos de mezcla producto del flujo de mareas. Lo que se evidenció en la presencia de fitoplancton oceánico, nerítico y estuarino; copépodos con distribución uniforme en el área de estudio y dominancia de la familia Engraulidae representativa en este tipo de ecosistema acuático en lo referente a larvas de peces. Temporalmente, mayo registró precipitaciones que excedieron los valores normales, lo que habría determinado las altas concentraciones de nutrientes, la disminución de salinidad y de la zona fótica, registradas en este mes. Sin embargo la disponibilidad de nutrientes existente permitió a lo largo de todo el período de estudio mantener la composición y abundancia del fitoplancton con alternancia de especies representativas y que el zooplancton registre periodos de mayor (junio a agosto) y menor (octubre a diciembre) abundancia, lo que sería resultado de patrones poblacionales específicos de las especies presentes e influencia de la marea y flujos del río aportante; comportamiento similar registró el ictioplancton resultado de las concentraciones de Anchoa macrolepidota, especie característica de este ecosistema. Estos patrones de distribución espacio-temporal, permiten establecer el desarrollo de múltiples interacciones abióticas y bióticas que determinan diferentes estrategias para mantener la productividad del área, por lo que se recomienda desarrollar esta investigación durante la estación lluviosa en el Ecuador.

Abstract El Oro includes different coastal and estuarine systems and the important Gulf of Guayaquil. These areas provide different ecosystem services, but with the increase of population and of the varied economic activities, the barely known local natural resources may be negatively impacted. Thus this research aimed to study plankton dynamics, productivity and ecological balance for the area during the dry season of 2012. For this, we established 17 stations and studied the monthly variation and spatial distribution of inorganic nutrients, temperature, dissolved oxygen, salinity, photic zone, plankton and fish larvae abundance and composition with standard methods, while spatial and temporal patterns where identified using cluster and multidimentional scaling analyses. Obtained results of biotic and abiotic parameters defined a pattern characteristic of productive estuarine zones as well as the existence of three specific areas associated with the natural and anthropic conditions of the area, such as: a) inner part of the Jambelí Archipelago and in front of Puná island influenced by productive activities and the hydrography of the area; B) an area, formed by the stations located in the outer estuary where the oceanic influence is evident and c) the Jambelí channel, characterized by mixing processes resulting from tides flow. This was supported by the presence of oceanic, neritic and estuarine phytoplankton; copepods with uniform distribution in the study area, and dominance of Engraulidae fish larvae, representative of this type of aquatic ecosystem. Temporally, rainfall records in May exceeded normal values, which would have influenced the high concentrations of nutrients, decrease of salinity and of the photic zone registered during this month. However, the availability of nutrients throughout the study period, allowed to maintain the composition and abundance of phytoplankton, with changes in representative species, recorded periods of greater (June to August) and lower (October to December) zooplankton abundance, could be the result of specific population patterns of present species, and the influence of the tide and the flows of the contributing river basin. A similar behavior was recorded for ichthioplankton, as a result of Anchoa macrolepidota concentrations, species, characteristics of this type of ecosystem. These patterns of spatio-temporal distribution, allowed the development of multiple abiotic and biotic interactions that determine different strategies to maintain the productivity of the area. We recommend new studies during the rainy season in Ecuador. Rev. Biol. Trop. 66(2): 836-847. Epub 2018 June 01.

Fish population responses to hydrological variation in a seasonal wetland in southeast México

Hydrological variation differently affects fish species. In the present study, the response of local populations of 13 fish local species to hydrological variation in a tropical wetland was evaluated. The objectives were to analyze the abundance response of fish species with distinct life history strategies and to assess the role of hydrological variation on fish population patterns. We found that opportunistic strategists were favored by high hydrological variation in drought periods, the equilibrium strategists were related to stable habitats, and periodic strategists were regulated by floods and temperature. However, the life history strategies identified for some species in this study do not correspond to the classification reported in other studies. Our results highlight the importance to study the abundance responses of species at local and regional scales to identify variations in life-history strategies, which can reflect local adaptations of species to hydrological changes, this is useful in order to understand and predict the responses of fish populations to the local environment.(AU)

La variación hidrológica afecta de manera diferencial a las especies de peces. En el presente estudio, se evaluó la respuesta de las poblaciones locales de 13 especies de peces considerando la variación hídrica en un humedal tropical. Los objetivos fueron analizar la respuesta de las abundancias de las especies de peces con diferentes estrategias de historia de vida e identificar la importancia de la variación hídrica en los patrones de las poblaciones de peces. Se encontró que los estrategas oportunistas fueron favorecidos por la alta variación hídrica en los periodos de sequía, los estrategas de equilibrio se relacionaron con hábitats estables, y que los estrategas periódicos son regulados por las inundaciones y la temperatura. Sin embargo, para algunas especies las estrategias de historias de vida identificadas en este estudio no corresponden a la clasificación reportada en otros estudios. Nuestros resultados resaltan la importancia de estudiar las respuestas de la abundancia de las especies a escalas locales y regionales para identificar las variaciones en las estrategias de historia de vida, las cuales pueden reflejar adaptaciones locales de las especies a cambios hídricos, esto es útil para entender y predecir las repuestas de las poblaciones de peces a los ambientes locales.(AU)

Balance de nitrógeno, fósforo y potasio en vacas Holstein pastando praderas de kikuyo (Cenchrus clandestinus) en el norte de Antioquia / Balance de nitrógeno, fósforo y potasio en vacas Holstein pastando praderas de kikuyo (Cenchrus clandestinus) en el norte de Antioquia / Balanço de nitrogênio, fósforo e potássio em vacas holandesas pastejando capim-quicuio (Cenchrus clandestinus) no Norte de Antioquia

Abstract To aim to estimate the balance of nitrogen (N), phosphorus (P) and potassium (K) in Holstein cows in northern Antioquia in the three thirds of lactation and in two seasons (high and low precipitation) grazing kikuyo grass (Cenchrus clandestinus), nine cows (three by lactation third) of five herds to which they estimated forage intake, consumption of food supplements and mineralized salt, were selected and were estimated excretion of feces, urine and milk secretion during last three days of an experimental period of 14 days in every season. Food samples, feces, urine and milk were taken in which the content of N, P and K were determined and digestibility, balance and efficiency of each nutrient in milk production were calculated. Data were analyzed under a completely randomized design in a factorial arrangement 3x2. With the advancement of lactation the efficiency of N, P and K decreased (p0.89) nor forage intake (p>0.24) were affected by reduced precipitation. It was conclude that the season can affect the balance and efficiency of nutrients in lactating cows mainly because management guidelines in the food supplement.

Con la finalidad de estimar el balance de nitrógeno (N), fósforo (P) y potasio (K) en vacas Holstein del norte de Antioquia en los tres tercios de la lactancia y en dos épocas del año (alta y baja precipitación) pastando praderas de kikuyo (Cenchrus clandestinus), se seleccionaron nueve vacas (tres de cada tercio) de cinco hatos a las que se les estimó el consumo de forraje, de los suplementos alimenticios y de sal mineralizada y se les estimó la excreción de heces, orina y la secreción láctea durante los últimos tres días de los 14 días que duraba el periodo experimental en cada época. Se tomaron muestras de los alimentos, heces, orina y leche en los que se determinó el contenido de N, P y K y se calculó la digestibilidad aparente, el balance y la eficiencia en el uso de cada nutriente en la producción de leche. Los datos se analizaron bajo un diseño completamente al azar en un arreglo factorial 3 x 2. Con el avance de la lactancia se redujo la eficiencia en el uso del N, P y K (p0,89) ni el consumo de la pradera (p>0,24) se vieran afectados. Se concluye que la época del año puede afectar el balance y eficiencia en el uso de los nutrientes en vacas lactantes debido principalmente a pautas de manejo en el suplemento alimenticio.

Resumo Com a finalidade de estimar o balanço de nitrogênio (N), fósforo (P) e potássio (K) em vacas holandesas do norte de Antioquia no terceiro tercio de lactação e em dois épocas do ano (alta e baixa precipitação) pastejando capim-quicuio (Cenchrus clandestinus), selecionaram-se nove vacas (três de cada tercio) de cinco rebanhos nas quais estimou-se o consumo de forragem, dos suplementos alimentícios e de sal mineralizada e além, estimou-se a excreção de fezes, urina e a secreção láctea durante os últimos três dias dos 14 que durava o período experimental em cada época. Tomaram-se amostras dos alimentos, fezes, urina e leite nos que se determinaram o conteúdo de N, P, e K e calcularam-se a digestibilidade aparente, o balanço e a eficiência no uso de cada nutrimento na produção de leite. Os dados analisaram-se sob um desenho completamente ao acaso num desenho fatorial 3 X 2. Com o avanço da lactação se reduz a eficiência no uso de N, P e K (p0,89), nem o consumo do capim (p>0,24), foram afetados. Conclui-se que a época do ano pode afetar o balanço e a eficiência no uso dos nutrientes para vacas em lactação devido principalmente as pautas de manejo no suplemento alimentício.

Steer performance on deferred pastures of Brachiaria brizantha and Brachiaria decumbens / Desempenho de novilhos de corte em pastos diferidos de Brachiaria brizantha e Brachiaria decumbens

ABSTRACT: The objective of this study was to compare structural, morphological and bromatological characteristics of forage as well as performance of Caracu beef cattle (200 ± 9 kg of initial body weight) supplemented with a multi-mineral mixture (0.25% of body weight) on deferred pastures of Brachiaria brizantha 'Marandu' and Brachiaria decumbens 'Basilisk' under continuous grazing. After the pasture was grazed to 10 cm of height, in March 2014, both grasses were left to rest and subjected to a 126-day deferment period. The experimental period lasted from July to October 2014; the sward characteristics and the animal's weight were evaluated every 28 days. The highest forage mass was recorded in 'Marandu' grass, whereas the highest leaves percentage and lowest dead material percentage were observed in 'Basilisk' pastures. Similarly, the highest crude protein content (8.1 vs. 7.0 ± 0.2%), in vitro organic matter digestibility (57.7 vs. 53.9 ± 0.4%), lowest neutral detergent fiber content (69.2 vs. 72.7 ± 0.4%), and; consequently, the highest average daily gain (680 vs. 530 ± 0.04g animal-1) were recorded for 'Basilisk' pastures. 'Marandu' and 'Basilisk' deferment was associated with a multi-mineral mixture supplementation as a management alternative for rearing beef cattle during the drought periods. Because of the duration of the pasture recovery period in this study, B. decumbens pastures were more likely to achieve the highest animal performance.

RESUMO: O objetivo deste trabalho foi comparar as características estruturais, morfológicas e bromatológicas da forragem e o desempenho de bovinos de corte, da raça Caracu (200±9kg de peso inicial), suplementados com mistura mineral múltipla (0,25% do peso corporal) em pastos diferidos de Brachiaria brizantha , cv. 'Marandu', e Brachiaria decumbens , cv. 'Basilisk', sob pastejo contínuo. Após o rebaixamento dos pastos a 10cm de altura, realizado em março de 2014 por meio de pastejo, ambas as espécies foram vedadas e diferidas por 126 dias. O período experimental foi de julho a outubro de 2014, e as avaliações das características do pasto e as pesagens dos animais foram realizadas a cada 28 dias. A maior massa de forragem foi registrada em pastos de 'Marandu'. A maior porcentagem de folhas e a menor de material morto foram observadas para a 'Basilisk'. Os maiores teores de proteína bruta (8,1 vs 7,0 ± 0,2%), digestibilidade in vitro da matéria orgânica (57,7 vs 53, 9 ± 0,4%), os menores teores de fibra em detergente neutro (69,2 vs 72,7 ± 0,4%) e, consequentemente, o maior ganho médio diário (680 vs 530 ± 0,04g animal-1) foram registrados para a cv. 'Basilisk'. O diferimento de pastagens de 'Marandu' ou 'Basilisk' associado à suplementação com mistura mineral múltipla figura como alternativa de manejo para recria de bovinos de corte durante o período seco. Para a duração do período de vedação utilizada, pastos de B. decumbens são mais indicados para alcançar o maior desempenho animal.

Seasonal variation in secondary sex ratio in Edo State, Nigeria: a retrospective study

Season is known to influence human secondary sex ratio but information on this subject is lacking in Nigeria. The objective of this study was to determine the secondary sex ratio (SSR) during the wet and dry seasons in Nigeria. In this retrospective cohort study, the records of all deliveries at St Philomena Catholic Hospital (SPCH), Benin City, Edo State, Nigeria between 1st January, 2005 and 31st December, 2014 (10 years) were retrieved and analyzed. The births were recorded according to the year and month of delivery. Stillbirths and infants with ambiguous genitalia were excluded from the analyses. The total number of live-births during the 10-year period under review was 13,702 and this consisted of 7,007 males and 6,695 females, resulting in a secondary sex ratio of 104.6:100 (1.05:1). In general, the monthly distribution of births was bimodal with a greater peak in May and a lesser peak in October with the highest and lowest SSRs in the months of June and March, respectively. In the dry season, the proportion of male births was higher than the proportion of female births; p > 0.05. In contrast, in the wet season the proportion of male births was lower than the proportion of female births; p > 0.05. In addition, the SSR was higher in the dry season (1.04) compared with the wet season (0.99). In Edo State, Nigeria, the proportion of male births tended to be higher than the proportion of female births during the dry seasons.

Levels of supplementation for grazing pregnant beef heifers / Níveis de suplementação para novilhas de corte prenhes em pastejo

The objective of this work was to evaluate the effect of different levels of multiple supplement supply on the nutritional characteristics and productive performance of pregnant heifers grazing Brachiaria decumbens Stapf. during the dry season. The experimental area was composed of four 3.0-ha paddocks with potentially digestible dry matter availability of 1,863 kg/ha. Twenty four crossbred heifers at 32 months and average initial body weight of 416±6 kg were used. The experimental design was in a completely randomized. The treatments consisted of mineral supplement and supply 0.5, 1.0, 2.0 kg/animal/day of multiple supplement. The dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), non-fibrous carbohydrates and total digestible nutrients (TDN) intake showed increasing linear relationship (P<0.10) with multiple supplement levels. Coefficients of apparent digestibility of DM, OM and non-fibrous carbohydrates also had linear effect (P<0.10) on the multiple supplementation levels. The microbial nitrogen flow and efficiency there was not affect (P>0.10) by levels of multiple supplementation; however the microbial nitrogen flow in relation to nitrogen intake showed decreasing linear profile (P<0.10). On the average daily gain was observed quadratic effect of multiple supplementation (P<0.10). In conclusion, the supply of 1.5 kg of multiple supplement optimizes the performance of grazing heifers during the dry season.

Objetivou-se avaliar o efeito do fornecimento de diferentes níveis de suplemento múltiplo sobre as características nutricionais e o desempenho produtivo de novilhas prenhes sob pastejo em Brachiaria decumbens Stapf. no período da seca. A área experimental constituiu-se de quatro piquetes de 3,0 hectares cada, com disponibilidade média de matéria seca potencialmente digestível (MSpd) de 1863 kg/ha. Os animais experimentais foram 24 novilhas prenhes mestiças com predominância de sangue zebuíno com idade e peso médio inicial de 32 meses e 416±6 kg, respectivamente, em um delineamento inteiramente casualizado. Os tratamentos consistiram em suplemento mineral e fornecimento de 0,5; 1,0 e 2,0 kg/animal/dia de suplemento múltiplo. Verificou-se efeito quadrático dos níveis de fornecimento de suplemento múltiplo (P<0,10) sobre o ganho médio diário. Os consumos de matéria seca (MS), matéria orgânica (MO), proteína bruta, extrato etéreo, carboidratos não fibrosos (CNF) e nutrientes digestíveis totais apresentaram relação linear crescente (P<0,10) com os níveis de fornecimento de suplemento múltiplo. Os coeficientes de digestibilidade aparente da MS, MO e CNF apresentaram perfil linear crescente (P<0,10) para os níveis de suplementação múltipla. Não houve efeito dos níveis de suplementação múltipla sobre o fluxo de compostos nitrogenados microbianos e eficiência de síntese microbiana, mas o fluxo de compostos nitrogenados microbiano em relação ao nitrogênio ingerido apresentou perfil linear decrescente (P<0,10). O fornecimento de 1,5 kg de suplemento múltiplo otimiza o desempenho de novilhas prenhes em pastejo no período da seca, mas não influencia o consumo de matéria seca do pasto e o fluxo de compostos nitrogenados microbianos.

Richness and composition of macrophyte assemblages in four Amazonian lakes / Riqueza e composição da assembleia de macrófitas em quatro lagos amazônicos

Aquatic macrophytes are an important component in the structure of lakes in Neotropical floodplains, for example, because they support a high diversity of invertebrates and vertebrates. In this paper, we tested whether or not the variability of macrophyte assemblages is lower in spatially close quadrats than among quadrats of different lakes. The study was carried in four lakes in a large Amazonian floodplain (Purus river), where floating meadows were investigated. A total of 49 taxa of macrophytes were found. Five species dominated and three species were rare. Taxa richness, composition and beta diversity differed more between than within lakes. Because high beta diversity was found among the lakes, they should be considered individually important for maintaining the gamma diversity of macrophytes within the Purus River floodplain, and this should be considered in plans of lake management.

As macrófitas aquáticas são um importante componente para a estrutura de lagos neotropicais em planícies de inundação, porque suportam alta diversidade de invertebrados e vertebrados. Neste trabalho, nós testamos se a variabilidade da assembleia de macrófitas aquáticas é menor entre "quadrats" espacialmente próximos do que "quadrats" em lagos diferentes. O estudo foi desenvolvido em quatro lagos da planície amazônica (rio Purus), onde bancos flutuantes de macrófitas foram amostrados. Um total de 49 taxa de macrófitas foi encontrado. Cinco espécies dominaram e três espécies foram raras. A riqueza de taxa, composição e diversidade de espécies diferiram mais entre os lagos do que dentro dos lagos. Pela alta diversidade beta encontrada nos lagos, esses lagos devem ser considerados importantes individualmente para manter a diversidade gamma de macrófitas dentro da planície de inundação do rio Purus. Esse fato deve ser considerado em planos de manejo desses lagos de planície.

Spatial patterns of zooplanktivore Chirostoma species (Atherinopsidae) during water-level fluctuation in the shallow tropical Lake Chapala, Mexico: seasonal and interannual analysis

This study addresses the influence of water-level fluctuations on fish distribution at two temporal scales: seasonal (dry and rainy) and interannual (low and high volume conditions). The analysis of abundance relationships among three zooplanktivore Chirostoma species at fifteen sites in Lake Chapala, Mexico, revealed the significant influence of contrasting conditions (P=0.0002). Seasonally, segregation was more related to species dominance in the dry season and exclusively related to environmental characteristics in the rainy season. Interanually, biotic influence occurred in the shallowest and the deepest episodes of the lake. Environmental characteristics influenced species distribution when the lake reached 25 percent of its volume. Site, depth, temperature, and salinity were the leading factors influencing fish distribution. These results emphasize the necessity to implement different management strategies according to lake volume, particularly when a critical threshold is reached.

El presente estudio describe la influencia que tiene la fluctuación del nivel del agua en la distribución de los peces a dos diferentes escalas: estacional (estiaje y lluvias) e interanual (condiciones de bajo y alto volumen). El análisis de las relaciones de abundancia entre tres especies zooplanctófagas de Chirostoma en quince sitios del Lago de Chapala, México, reveló una influencia estadísticamente significativa en las condiciones contrastantes (P=0.0002). Estacionalmente, la segregación estuvo más relacionada a la dominancia de las especies en la época de estiaje y exclusivamente relacionada a las características ambientales en la época de lluvias. Interanualmente, la influencia biótica se presenta en los episodios más someros y más profundos del lago. Las características ambientales influenciaron la distribución de las especies cuando el lago alcanzó el 25 por ciento de su volumen. El sitio geográfico, profundidad, temperatura y salinidad fueron los principales factores que influenciaron la distribución de los peces. Estos resultados enfatizan la necesidad de implementar diferentes estrategias de manejo de acuerdo al volumen del lago, particularmente cuando se alcanza un umbral crítico.

Química de igarapés de água preta do nordeste do Amazonas - Brasil / Chemical composition of black water creeks from northern of Amazonas - Brasil

Neste estudo foram analisados pH, Eh, condutividade elétrica, cloreto, sílica, fosfato, K, Na, Ca, Mg, Fe, F, Zn, Ni, Co, Mn, Pb, Cu, Cr, Li e Cd nas águas de drenagens de pequeno porte no nordeste do Amazonas. As águas são pretas, predominantemente ácidas e levemente redutoras e com baixo conteúdo de elementos dissolvidos. Contudo, a química indica que são heterogêneas e refletem o ambiente geológico por onde percolam. SiO2, Na e K são os constituintes mais abundantes na fase dissolvida, especialmente nas drenagens mais a norte pertencentes as bacias do Uatumã, Urubu e no igarapé Canoas que drenam as rochas da Suíte Intrusiva Água Branca e Mapuera e as sedimentares do Grupo Iricoumé e as Formações Prosperança, Nhamundá, Manacapuru, Pitinga Os igarapés menores, que drenam exclusivamente os sedimentos da Formação Alter do Chão, são os mais diluídos. Os elementos-traços analisados estão em concentrações muito baixas.

The present study analyzed pH, Eh, electric conductivity, chloride, silica, phosphate, K, Na, Ca, Mg, Fe, Zn, Ni, Co, Mn, Pb, Cu, Cr, Li and Cd in draining waters making part of smaller creeks located in the northeastern Amazonas State. The waters have black colour, are predominantly acid and slightly reductive and have low content in dissolved elements. Otherwise they are chemically heterogeneous and reflect the geological environment. The SiO2, Na and K are the most abundant dissolved constituents, especially on the drainages farther north belonging to Uatumã, Urubu basins and Canoas Stream, which drain the rocks of Água Branca and Mapuera Intrusive Suite, Iricoumé Group and Prosperança, Nhamundá, Manacapuru, Pitinga Formations. Smaller Streams, which drains Alter do Chão Formation sediments, exclusively, are the most diluted ones. The analysed trace elements present very low concentrations.

A dimensão espacial e temporal da diversidade de peixes da zona litoral vegetada de lagoas marginais da planície de inundação do rio Cuiabá, Pantanal, Brasil / The spatial and temporal dimension of fish diversity of the vegetated littoral zone of marginal lagoons of the Cuiabá river floodplain, Pantanal, Brazil

O presente trabalho avaliou a distribuição espacial e temporal da riqueza de espécies de peixes da zona litoral vegetada de 15 lagoas marginais da planície de inundação do Rio Cuiabá, Pantanal. As lagoas foram amostradas em três períodos ao longo da sessão seca (junho, setembro e dezembro de 2005), por meio de nove lances de peneira, distribuídos sistematicamente a uma distância mínima de cinco metros um do outro. Capturamos 12.784 indivíduos pertencentes a sete ordens, 21 famílias e 98 espécies. A maioria das espécies capturadas foi rara e apresentou distribuição geográfica restrita. A intensificação da seca não afetou a distribuição espacial das espécies e a perda de espécies nas diferentes ordens, ao longo da seca, foi proporcional. Tanto a abundância total de indivíduos quanto a riqueza variou no tempo. As curvas de rarefação indicaram que a redução na riqueza foi um artefato da redução na abundância de indivíduos. Quando comparamos as riquezas estimadas sob um mesmo nível de abundância não encontramos diferença entre a riqueza de espécies no início e no final da seca. Os estimadores de riqueza de espécies indicaram que distribuir as amostras no tempo foi uma estratégia adequada para reduzir o problema das falsas ausências e melhorar a eficiência da amostragem. Assim, nossos resultados sugerem que para o delineamento de reservas no Pantanal, áreas com um grande número de lagoas com diferentes formas e tamanhos conservaria um maior contingente da diversidade regional de peixes, pois a maioria das espécies de pequeno porte apresenta distribuição restrita a poucas lagoas.

The present work has evaluated the spatial and temporal distribution of fish species richness of the vegetated littoral zone of 15 marginal lagoons in the floodplain of the Cuiabá River, Pantanal. The lagoons were sampled in three periods along of the dry season (June, September and December of 2005), through nine sieve throws distributed systematically at a minimum distance of five meters from each other. We caught 12,784 individuals belonging to seven orders, 21 families and 98 species of fish. Most of the captured species were rare and presented restricted geographical distribution. Drought intensification did not affect the spatial species distribution and the loss of species as dry season proceeded was proportional in the different orders. The total abundance of individuals as well as the richness varied with time. Rarefaction curves indicated that the reduction in richness was an artifact of the reduction in the abundance of individuals. When we compared the estimated richness under a same abundance level we did not find difference among the richness of species in the beginning and at the end of the dry season. Richness estimators indicated that to distribute the samples in the time was an appropriate strategy to reduce the problem of the false absences and to improve the efficiency of the sampling. Thus, our results suggest that for the design of reserves in the Pantanal, areas with a large number of lagoons of different forms and sizes would conserve the regional fish diversity, as the distribution of most small size species is restricted to a few lagoons.

Estratificação e densidade de invertebrados em solo arenoso sob floresta primária e plantios arbóreos na amazônia central durante a estação seca

Density and vertical distribution of soil invertebrates were studied during September of 1990 and 1991 in three plots, namely one forest plot and two arboreal plantations (Dipteryx odorata =cumaru Leguminosae> and Simaruba amara =marupá Simarubaceae>) near Manaus (Brazil). Nineteen main fauna groups were found, and most of them had similar densities in the three plots. The most representative groups were Isoptera (40.1 %), Formicidae (25.2%), Araneae (6.7%), all together representing 62.4% of all soil fauna in the cumaru plot, 57.0% in marupa and 84.1 % in the forest plot. Density of soil fauna decreased from the top soil to 20 cm depth (excluding termites), with a subsequent increase until 30 cm depth. 45% of all fauna occurred in the top 0-5 cm, followed by 9.5% (5-10 cm), 9.1 % ( 10-15 cm), 2.7% (15-20 cm), 20.7% (20-25 cm) and 12.3% (25-30 cm). Isoptera, Diptera and other invertebrates did not present correlation with the pH and the humidity of the soil.

Densidade e distribuição vertical de invertebrados foram estudados durante o mês de setembro de 1990 e 1991, em solo de três tipos de cobertura vegetal: floresta primária, plantios de Dipteryx odorata(Leguminosae = cumaru) e Simaruba amara(Simarubaceae = marupá), nos arredores de Manaus, Brasil. Foram encontrados 19 grupos principais da fauna. A maioria desses grupos foram similares para os três tipos de cobertura, sendo Isoptera (40,1%), Formicidae (25,2%), Araneae (6,7%) os grupos mais abundantes que, juntos, representaram 62,4% da fauna de cumaru, 57,0% da fauna de marupá e 84,1% da fauna de floresta. Houve uma diminuição da densidade para todos os grupos (excluídos os cupins) até a profundidade de 20 cm, com subseqüente aumento até 30 cm de profundidade, principalmente pela presença de Isoptera. Cerca de 45% de toda a fauna ocorreu no estrato de 0-5 cm de profundidade, seguido de 9,5% (5-10 cm), 9,1% (10-15 cm), 2,7% (15-20 cm), 20,7% (20-25 cm) e 12,3% (25-30 cm) nos estratos subseqüentes. Isoptera, Diptera e outros invertebrados não apresentaram correlação com a umidade e o pH do solo.