Abstract The present study aimed to produce a monosex population of all male Nile tilapia (Oreochromis spp.) using 17α-methyl testosterone and common carp testes (as a source of natural androgen). Trial was conducted into two consecutive phases, the first was fry (4-5 days old)administration with negative control (without hormone) and positive control (with hormone) feed viz., MT1:60mg/kg, MT2:70mg/kg (17α-MT), carp testis CT1:70% and CT2:80% for 30 days to reverse the sex of male fish and the second phase was nursing the fingerlings for two months on control diet (32% Crude protein).Results revealed a significant growth rate (P<0.05) in the control group where final weight (4.8±0.34ab) and weight gained was recorded as 0.66±0.03ac. In proximate chemical composition of body meat, CT2 treatment showed maximum retention of crude protein, crude fat, and ash whereas dry matter showed maximum retention in MT2 and CT1 treatments. Morphological and histological examination revealed significant difference (p<0.05) in phenotypic males of Nile tilapia fed with the highest percent in MT-treated diet (MT2) of 95±0.58a while MT1, CT2 and CT1 had males of 85±6.0b, 70±5.0b and 65±6.5b, respectively. It was concluded that synthetic androgen (17αMT) was more effective for masculinization but natural androgen scan be an alternative method to produce male tilapia population in an environment-friendly manner as they are inexpensive, eco-friendly, and radially available. These results suggested that synthetic and natural androgen supplementation in the diet plays a significant role in improving growth performance and body composition.

Resumo O presente estudo teve como objetivo produzir uma população monossexuada de todos os machos de tilápia do Nilo (Oreochromis spp.) usando 17α-metil testosterona e testículos de carpa comum como fonte de andrógeno natural. O ensaio foi conduzido em duas fases consecutivas, a primeira foi a administração de alevinos (4-5 dias) com controle negativo (sem hormônio) e controle positivo (com hormônio), viz., MT1:60mg/kg, MT2:70mg/kg (17α -MT), testículos de carpa CT1:70% e CT2:80% por 30 dias para inverter o sexo dos peixes machos e a segunda fase foi amamentar os alevinos por dois meses com dieta controle (32% de proteína bruta), e analisar a taxa de crescimento (p < 0,05) no grupo controle, em que o peso final (4,8 ± 0,34 ab) e o peso ganho foram registrados como 0,66 ± 0,03 ac. Na composição química aproximada da carne corporal, o tratamento CT2 mostrou retenção máxima de proteína bruta, gordura bruta e cinzas, enquanto a matéria seca apresentou retenção máxima nos tratamentos MT2 e CT1. O exame morfológico e histológico revelou diferença significativa (p < 0,05) nos machos fenotípicos de tilápia do Nilo alimentados com o maior percentual na dieta tratada com MT (MT2) de 95 ± 0,58a enquanto MT1, CT2 e CT1 tiveram machos de 85 ± 6,0b, 70 ± 5,0 e 65 ± 6,5b, respectivamente. Concluiu-se que o andrógeno sintético (17αMT) foi mais eficaz para a masculinização, entretanto os andrógenos naturais podem ser um método alternativo para produzir população de tilápias machos de maneira ecológica, pois são baratos, ecológicos e estão disponíveis radialmente. Esses resultados sugerem que a suplementação de andrógenos sintéticos e naturais na dieta desempenha um papel significativo na melhoria do desempenho do crescimento e da composição corporal.

Resumo Anredera cordifolia (Ten.) Steenis é uma trepadeira nativa do Brasil considerada uma planta alimentícia não convencional e uma espécie medicinal, cujos compostos fenólicos exercem ação antioxidante. Como a produção de metabólitos é determinada por fatores ambientais e pela maturidade das folhas, é importante acompanhar essas mudanças a fim de determinar a época de colheita. Neste estudo objetivou-se verificar se a fenologia foliar e a sazonalidade ocasionam variação na quantidade de compostos fenólicos e na ação antioxidante dessa espécie. As folhas foram coletadas em diferentes estações, entre setembro de 2018 e abril de 2019, e separadas conforme a maturidade: jovens, maduras e senescentes. Os dados diários de temperatura atmosférica e pluviosidade foram usados para caracterizar o período de coleta. O conteúdo de fenólicos totais (TPC), determinado pelo método Folin-Ciocalteu, foi significativamente maior nas folhas jovens coletadas no inverno, período caracterizado por temperaturas mais baixas. Estas folhas apresentaram 54,4 mg equivalentes de ácido gálico por 100 g de matéria seca (mg GAE 100 g-1DM) . A média dos outros resultados foi de 25,6 mg GAE 100 g-1DM. A maior ação antioxidante, avaliada pelo método do radical livre 2,2-difenil-1-picrilhidrazil (DPPH), foi observada em folhas colhidas no outono (73,7%) e inverno (71,1%), independentemente da fenologia foliar. Nestes períodos a pluviosidade foi menor. Folhas colhidas no verão e na primavera apresentaram menores percentuais de ação antioxidante (54,3 e 37,5%, respectivamente). Não houve correlação significativa entre o conteúdo de fenólicos totais e a atividade antioxidante. Conclui-se que a composição fenólica de A. cordifolia e, consequentemente, sua ação sobre radicais livres, varia sazonalmente em resposta à temperatura e pluviosidade, podendo ou não interagir com a idade das folhas.

Abstract Anredera cordifolia (Ten.) Steenis is a vine species native to Brazil that is considered an unconventional food plant and a medicinal species whose phenolic compounds exert antioxidant activity. Since the production of metabolites is determined by environmental factors and leaf maturity, it is important to track these changes in order to determine the best time to harvest. This study aimed to verify whether leaf phenology and seasonality cause variations in the amount of phenolic compounds and in the antioxidant activity of this species. The leaves were collected in different seasons between September 2018 and April 2019, and separated according to maturity: young, mature, and senescent. Daily atmospheric temperature and rainfall data were used to characterize the collection period. The total phenolic content (TPC), determined by Folin-Ciocalteu method, was significantly higher in the young leaves collected in winter, a season of lower temperatures. These leaves showed 54.4 mg of gallic acid equivalents per 100 g of dry matter (mg GAE 100 g-1DM). Other results averaged 25.6 mg GAE 100 g-1DM. The highest antioxidant activity, assessed via the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, regardless of leaf phenology, was observed in leaves harvested in autumn (73.7%) and winter (71.1%), seasons with lower rainfall. Leaves harvested in summer and spring had lower antioxidant action rates (54.3 e 37.5%, respectively). There was no significant correlation between the total phenolic content and antioxidant activity. Thus, the phenolic composition of A. cordifolia, and consequently its activity on free radicals, varies seasonally in response to temperature and rainfall, and may or may not interact with the age of the leaves.

Resumo Este estudo objetivou analisar a dieta do cachorro-do-mato, de vida livre, por meio da identificação do conteúdo estomacal de 17 Cerdocyon thous atropelados em duas unidades de conservação da Floresta Amazônica. O conteúdo estomacal foi analisado e os itens alimentares foram quantificados pela frequência de ocorrência (FO) e percentagem de ocorrência (PO). Também foram avaliados os teores de matéria seca (MS), proteína bruta (PB), fibra bruta (FB), extrato etéreo (EE) e, matéria mineral (MM). Foram estimados o extrativo não-nitrogenado (ENN), a energia metabolizável (EM) e a necessidade energética de manutenção. A composição da dieta do cachorro-do-mato apresentou 29 itens alimentares dos diferentes grupos taxonômicos, tendo uma maior diversidade de itens de origem animal (n=22), ainda que a maior FO tenha sido de gramíneas (Poaceae) (41.18%). Dentre os itens de origem animal, 21% eram mamíferos, 18% répteis, 10% anfíbios, 9% invertebrados e 3% aves. Determinou-se um alto teor de FB (62.76%). A média do ENN e da MS foi 5.91% e 141.82 kcal/100g, respectivamente. A média da energia de manutenção foi 447.01 kcal/dia. Estes achados sugerem que o cachorro-do-mato encontrado na Bacia Amazônica é um animal generalista com uma dieta onívora, se alimentando de gramíneas, frutos, insetos, serpentes, anfíbios, aves e pequenos mamíferos, portanto com o mesmo hábito alimentar relatado a esta espécie quando encontrada em outros biomas brasileiros.

Abstract The present study aimed to evaluate the diet of the free-living crab-eating fox by identifying the stomach contents of the 17 crab-eating foxes (Cerdocyon thous) roadkilled in two conservation units, both located in the Amazon rainforest. The food items were quantified by frequency of occurrence (FO) and percentage of occurrence (PO). The stomach contents were analysed for dry matter (DM), crude protein (CP), crude fibre (CF), ether extract (EE), and mineral matter (MM). Nitrogen-free extractives (NFE), metabolisable energy (ME) values, as well as the energy need for maintenance were estimated. The composition of the diet for the crab-eating fox presented 29 food items from the different taxonomic groups, with a greater diversity of items of animal origin (n=22), although the highest frequency of occurrence was gramineae (Poaceae) (41.18%). Among the items of animal origin, 21% were mammals, 18% reptiles, 10% amphibians, 9% invertebrates and 3% birds. A high content of CF (62.76%) were determined. Nitrogen-free extractive and dry matter averages were 5.91% and 141.82 kcal/100g, respectively. The average maintenance energy was 447.01 kcal/day. These findings suggesting that the crab-eating foxes have a generalist diet with an omnivorous diet in the Amazon basin, feeding on gramineae, fruits, insects, snakes, amphibians, birds and small mammals and have the same feeding habit that present in other Brazilian biomes.

Resumo A pitaia vermelha (Hylocereus costaricensis) é uma promissora espécie, com elevado potencial de cultivo devido às qualidades organolépticas e funcionais de seus frutos. Entretanto, a salinidade da água de irrigação pode afetar o rendimento produtivo da cultura. Diante disso, materiais ricos em substâncias orgânicas podem minimizar os danos provocados pelo excesso de sais no solo e/ou na água. Assim, o objetivo deste trabalho foi avaliar a influência de fontes de matéria orgânica como atenuante do estresse salino na produção e respostas bioquímicas de mudas de pitaia vermelha. O delineamento inteiramente casualizado em esquema fatorial 4 × 5, com cinco fontes de matéria orgânica (húmus, esterco ovino, biofertilizante, composto orgânico e areia + solo) e quatro salinidade (0.6, 2.6, 4.6 e 6.6 dS m-1), com quatro repetições e duas plantas por vaso foi utilizado. O comprimento da parte aérea, comprimento da raiz, diâmetro do cladódio, número de cladódios, número de brotos, volume da raiz, massa seca da parte aérea, massa seca da raiz e massa seca total, razão da massa seca da raiz e da parte aérea, clorofila a, b e total, aminoácidos e os açúcares solúveis foram avaliados aos 120 dias após o início da aplicação dos tratamentos. A pitaia vermelha é moderadamente tolerante a salinidade. O composto orgânico e estrume ovino atenuam os efeitos nocivos da salinidade nas mudas de pitaia vermelha. Sob condições de estresse salino, as plantas aumentam os níveis de aminoácidos e açúcares totais.

Abstract Red pitaya (Hylocereus costaricensis) is a promising species, with high cultivation potential due to the organoleptic and functional qualities of its fruits. However, irrigation water salinity can affect the crop yield. Therefore, materials rich in organic substances can minimize the damage caused by excess salts in soil and/or water. Thus, the objective of this study was to evaluate the influence of organic matter sources as attenuators of salt stress on the production and biochemical responses of red pitaya seedlings. A completely randomized design in 4 × 5 factorial scheme, with five sources of organic matter (humus, sheep manure, biofertilizer, organic compost and sand + soil) and four salinities (0.6, 2.6, 4.6 and 6.6 dS m-1) with four replicates and two plants per plot was used. The shoot length, root length, cladode diameter, number of cladodes, number of sprotus, root volume, shoot dry mass, root dry mass and total dry mass, root and shoot dry mass ratio, chlorophyll a, b and total, amino acids and soluble sugars were evaluated at 120 days after the treatments began to be applied. Red pitaya is moderately tolerant to salinity (ECw from 4.0 to 6.0 dS m-1). Organic compost and sheep manure attenuate the harmful effects of salinity on red pitaya seedlings. Under salt stress conditions, red pitaya plants increase their levels of proline, amino acids and total sugars.

Resumo Hoje, o milho doce é considerado uma hortaliça importante devido ao seu alto teor de açúcar e baixo teor de amido. A análise de agrupamento e a análise de variância mostraram que os híbridos apresentaram variações nos índices de produtividade. Os híbridos GB, DE e GS tiveram desempenho semelhante nos índices. Híbrido SE que apresenta desempenho significativo sobre a zeaxantina. Biplot mostrou que frutose, glicose, sacarose e potássio apresentaram valor de estabilidade em híbridos. Todos os híbridos tiveram o melhor desempenho nos fatores frutose, glicose, sacarose e potássio. O fator biplot correlacionou-se positivamente com os índices de rendimento, incluindo cálcio, ferro, zinco, magnésio, α-caroteno, 9Z-β-caroteno, fósforo e β-caroteno. Por outro lado, há correlação positiva com frutose, glicose, potássio, luteína, sacarose, β-criptoxantina e zeaxantina. Assim, para avaliar ou aumentar a luteína e a zeaxantina, outros parâmetros como o teor de açúcares (frutose, glicose e sacarose) são fatores importantes e atuam em conjunto. A análise fatorial e o biplot mostraram que o híbrido ME apresentou desempenho máximo no primeiro fator de índices de produtividade. Além disso, o segundo fator de índices de produtividade teve um efeito máximo nos híbridos de NO. Os híbridos SE tiveram desempenho máximo em zeaxantina e o híbrido GS teve desempenho máximo em zinco, fósforo e ferro. A matéria seca apresentou estabilidade no híbrido DB.

Abstract Today, sweet corn is considered an important vegetable due to its high sugar content and low starch content. Cluster analysis and variance analysis showed that hybrids had variations in yield indices. GB, DE and GS hybrids had similar performance on indices. SE hybrid that has significant performance on zeaxanthin. Biplot showed that fructose, glucose, sucrose and potassium had stability value on hybrids. All the hybrids had the best performance on fructose, glucose, sucrose and potassium factors. Factor biplot positively correlated with yield indices, including calcium, iron, zinc, magnesium, α-Carotene, 9Z-β-Carotene, phosphorus, and β-carotene. On the other hand, there is a positive correlation with fructose, glucose, potassium, lutein, sucrose, β-Cryptoxanthin, and zeaxanthin. So, to evaluate or increase lutein and zeaxanthin, the other parameters like sugar content (fructose, glucose, and sucrose) are important factors and have an effect together. Factor analysis and biplot showed that ME hybrid had a maximum performance on the first factor of yield indices. Also, the second factor of yield indices had a maxi-mum effect on NO hybrids. SE hybrids had maximum performance in zeaxanthin and GS hybrid had maximum performance in zinc, phosphorus, and iron. The dry matter had stability on DB hybrid.

Resumen Introducción. Los sistemas de producción de huevo son fundamentales para la seguridad alimentaria. Las preocupaciones alrededor del bienestar animal incrementan el interés por los sistemas de producción de huevo con acceso a pastoreo. Objetivo. Describir los rendimientos productivos, características morfológicas y calidad nutricional de los huevos de gallinas ponedoras de la línea genética ISA Brown en un sistema de piso con acceso a pastoreo. Materiales y métodos. La investigación se llevó a cabo entre julio del 2018 y enero del 2020 en el cantón central de Turrialba, Cartago, Costa Rica, con gallinas de la línea genética ISA Brown con acceso a pastoreo. Se compararon los rendimientos productivos con el estándar de la línea genética. Se evaluaron variables morfológicas externas e internas del huevo y se caracterizó el contenido nutricional del mismo (materia seca, proteína cruda, extracto etéreo, cenizas, calcio, fósforo, ácidos grasos saturados (AGS), monoinsaturados (AGMI) y poliinsaturados (AGPI)), en gallinas de diferentes edades. Resultados. Los rendimientos productivos no distaron del estándar de la genética. El aumento en la edad del ave tuvo una influencia estadísticamente significativa sobre el incremento en el peso del huevo y de la cáscara, y la disminución del índice morfológico. El análisis nutricional indicó que el aumento en la edad de la gallina disminuyó el contenido de materia seca y la concentración de AGS y AGMI en el huevo. La relación AGPI/AGS de los huevos fue superior a 0,45, indistintamente de la edad de la gallina ponedora. Conclusión. Los indicadores productivos de las galinas con acceso a pastoreo no presentaron diferencias con los estándares de la línea genética ISA Brown para sistemas alternativos. El peso, el índice de yema, las unidades Haugh y el índice morfológico del huevo variaron con la edad de la gallina.

Abstract Introduction. Egg production systems are critical to food security. Concerns about animal welfare are increasing the interest in egg production systems with access to grazing. Objective. To describe the productive performances, morphological characteristics, and nutritional quality of the eggs from laying hens of the Isa Brown genetic line in a floor system with access to grazing. Materials and Methods. The research was carried out between July 2018 and January 2020 in the central canton of Turrialba, Cartago, Costa Rica, with hens of the Isa Brown genetic line with access to grazing. Productive performances were compared with the standard of the genetic line. External and internal morphological variables of the egg were evaluated and its nutritional content (dry matter, crude protein, ethereal extract, ash, calcium, phosphorus, saturated fatty acids (SFA), monounsaturated (MUFA), and polyunsaturated (PUFA) was characterized in hens of different ages. Results. The productive performances was not different from the genetic standard. The increase in bird age had a statistically significant influence on the increase in egg and shell weight, and the decrease in morphological index. Nutritional analysis indicated that increasing hen age decreased the dry matter content and the concentration of SFA and MUFA in the egg. The PUFA/SFA ratio of the eggs was higher than 0.45, regardless of the age of the laying hen. Conclusion. The productive indicators of the hens with access to grazing did not differ from ISA Brown genetic line standards for alternative systems. Egg weight, yolk index, Haugh units, and morphology index varied with the age of the hen.

Resumen Introducción. El consumo y la digestibilidad son parámetros que definen la calidad de un forraje, sin embargo, son difíciles y costosos de estimar. La tecnología espectroscopía de infrarrojo cercano aplicada a las heces (NIRSf) es una alternativa a los métodos convencionales de referencia para estimar el consumo voluntario (CVMS) y digestibilidad de materia seca (DMS) en ovinos. Objetivo. Comparar la tecnología NIRSf con métodos convencionales para la estimación de CVMS y DMS en ovinos en confinamiento. Materiales y métodos. Se realizaron seis bioensayos en el centro de investigación Tibaitata, Cundinamarca, Colombia, durante los años 2019 y 2021 con cinco ovinos (PV 58,28±11 kg) para estimar CVMS y DMS por tres métodos: gravimetría, marcadores y NIRSf. Los animales fueron alimentados con seis regímenes alimenticios contrastantes en su valor nutricional. Se colectaron muestras de forrajes y heces, las cuales se secaron y molieron para su posterior análisis químico y espectral. Resultados. La estimación de CVMS y DMS fue diferente (p<0,001) en los seis regímenes alimenticios evaluados, donde el CVMSPM varió de 37,54 a 82,58 g/kg PV0,75 y la DMS varió de 36,32 a 58,81 %. En la comparación de la estimación del CVMS y DMS por el método referente (gravimétrico) con los métodos de marcadores y NIRSf, se observó que el método NIRSf presentó mejor ajuste comparado con el de marcadores, al presentar menor valor de la raíz del cuadrado medio del error (-1,53 y -1,75, respectivamente), menor error medio absoluto (-3,01 y -0,5, respectivamente) y mayor coeficiente de determinación (+0,09 y +0,28, respectivamente). Conclusión. La estimación del CVMS y la DMS por medio de ecuaciones NIRSf presentó mejor ajuste comparado con la metodología de marcadores; sin embargo, es necesario mejorar la precisión de las calibraciones con muestras de heces de animales bajo diferentes contextos productivos.

Abstract Introduction. Intake and digestibility are parameters that define the quality of a forage; however, they are difficult and expensive to estimate. Near infrared spectroscopy technology applied to feces (NIRSf) is an alternative to conventional reference methods to estimate dry matter voluntary intake (DMVI) and digestibility (DMD) in sheep. Objective. To compare NIRSf technology with conventional methods for estimation of DMVI and DMD in confinement sheep. Materials and methods. Six bioassays were carried out at the Tibaitata research center, Cundinamarca, Colombia, during 2019 and 2021 with five sheep (LW 58.28±11 kg) to estimate DMVI and DMD by three methods: gravimetry, markers and NIRSf. The animals were fed six diets contrasting in their nutritional value. Forage and feces samples were collected, dried, and ground for subsequent chemical and spectral analysis. Results. The estimation of DMVI and DMD was different (p<0.001) in the six evaluated feeding regimenes, where the DMVIMW ranged from 37.54 to 82.58 g/kg LW0.75, and the DMD ranged from 36.32 to 58.81 %. In the comparison of the estimation of DMVI and DMD by the referent method (gravimetric) with marker and NIRSf methods, shows that the NIRSf method presented a better adjustment compared to the marker method, presenting less root mean square error value (-1.53 and -1.75, respectively), lower mean absolute error (-3.01 and -0.5, respectively), and higher determination coefficient (+0.09 and +0.28, respectively). Conclusion. The estimation of the DMVI and the DMD by means of the NIRSf equations presented a better fit compared to the marker method, however, it is necessary to improve the accuracy of the calibrations using feces samples from animals under different productive contexts.

Resumen Introducción. Para el establecimiento adecuado de plantaciones de cacao, se deben garantizar tecnologías idóneas para la obtención de posturas (plantas jóvenes sembradas y desarrolladas en bolsas) de calidad en los viveros. Objetivo. Definir indicadores de calidad para posturas de cacao producida vía micro injertos, en función de las fuentes orgánicas y hongos micorrízicos arbusculares en un suelo Cambisol. Materiales y métodos. Entre 2018 y 2019, en el vivero de la Empresa Agroforestal y Coco de Baracoa, se evaluó la inoculación de las cepas Glomus cubense y Rhizoglomus irregulare en sustratos formados por humus de lombriz y cáscara de cacao compostada (3:1,5:1 v/v). Se utilizó un diseño completamente aleatorizado, con cincuenta posturas por tratamiento, de ellas se evaluaron veinticinco. A los cuatro meses se evaluó: altura, diámetro del tallo, masa seca aérea, radical y total, concentración de nutrientes foliares (N, P, K), área foliar, índice de esbeltez, índice de calidad Dickson (ICD) y porcentaje de colonización micorrízica. Se realizó un análisis de varianza de clasificación simple y se aplicó la prueba de comparación de Duncan (95 %). Resultados. La inoculación de G. cubense y R. irregulare, independiente de la fuente de abono orgánico, incrementaron significativamente la masa seca total (39 %), el área foliar (20 %) y el ICD (48 %), respecto los testigos. El ICD se relacionó significativamente (p<0,05) con la masa seca total y el área foliar (R2= 0,97). La inoculación con R. irregulare y G. cubense incrementaron las concentraciones foliares de N, P y K. Conclusiones. Las variables masa seca total, el área foliar, el índice de esbeltez y el ICD, mostraron un carácter integrador del crecimiento de la planta y pueden ser indicadores de calidad para los micro injertos de cacao, a partir de relaciones suelo : abonos orgánicos e inoculación con G. cubense y R. irregulare.

Abstract Introduction. For the proper establishment of cocoa plantations, suitable technologies must be guaranteed to obtain quality seedlings (young plants sown and developed in bags) in the nurseries. Objective. To define quality indicators for cocoa seedlings produced via micro-grafting, depending on organic sources and arbuscular mycorrhizal fungi in a Brown Sialitic soil. Materials and methods. Between 2018 and 2019 in the nursery of the Empresa Agroforestal y Coco de Baracoa, the inoculation of the Glomus cubense and Rhizoglomus irregulare strains in substrates formed by earthworm humus and composted cocoa husk (3:1,5:1 v/v) was evaluated. A completely randomized design was used, with 50 postures per treatment, of which 25 were evaluated. At four months, the following were evaluated: plant height, stem diameter, aerial, root and total dry mass, foliar nutrient concentration (N, P, K), leaf area, slenderness index, Dickson Quality Index (DQI), and the percentage of mycorrhizal colonization. A simple rank analysis of variance was performed and Duncan’s comparison test (95 %) was applied. Results. The inoculation of G. cubense and R. irregulare, regardless of the source, significantly increased total dry mass (39 %), the leaf area (20 %) and the DQI (48 %) with respect to the controls. The DQI was significantly related (p<0.05) to total dry mass and leaf area (R2= 0.97). The inoculation with R. irregulare and G. cubense increased the leaf N, P, and k concentrations. Conclusions. The variables total dry mass, leaf area, slenderness index, and DQI showed an integrative character of plant growth and can be used as quality indicators for cocoa micro-grafts, based on soil : organic fertilizer relationships and inoculation with G. cubense and R. irregulare.

ABSTRACT The aim of this study was to evaluate the effect of exogenous amylase on gas production, in vitro dry matter digestibility (IVDMD), and in vitro digestion kinetics of sorghum (Sorghum vulgaris) and two corn hybrids of different grain textures. Ruminal fluid was collected from two rumen-fistulated cows receiving or not exogenous amylase (0.7g kg-1 of dry matter (DM basis)), provided to achieve 396 kilo Novo units kg-1 for amylase activity (DM basis). Gas production was measured after 1, 3, 6, 9, 12, 15, 18, 21, 24, 30, 36, 42 e 48 hours of incubation. Amylase increased gas production (mL) by 5.4%. Corn hybrids have higher in vitro dry matter digestibility than sorghum. Exogenous amylase increased the potential of gas production (A) (P=0.01). There was an effect of hybrid for IVDMD (P<0.01). The addition of exogenous amylase increases the in vitro gas production, improves fermentation kinetics, and increases the production of the ammonia nitrogen of corn and sorghum grains, but does not affect in vitro and dry matter digestibility or the short-chain fatty acids production.

RESUMO O objetivo deste estudo foi avaliar o efeito da amilase exógena na produção de gases, a digestibilidade in vitro da matéria seca (DIVMS) e a cinética de digestão in vitro de sorgo (Sorghum vulgaris) e de dois híbridos de milho de diferentes texturas de grãos. O líquido ruminal foi coletado de duas vacas fistuladas no rúmen recebendo ou não amilase exógena (0,7g kg-1 de matéria seca (MS)), fornecida para atingir 396 kg Novo unidades kg-1 para atividade de amilase (base na MS). A produção de gás foi medida após uma, três, seis, nove, 12, 15, 18, 21, 24, 30, 36, 42 e 48 horas de incubação. A amilase aumentou a produção de gás (mL) em 5,4%. Híbridos de milho apresentam maior DIVMS que o sorgo. A amilase exógena aumentou o potencial de produção de gás (A) (P=0,01). Houve efeito de híbrido para DIVMS (P<0,01). Amilase exógena aumenta a produção de gás in vitro, melhora a cinética da fermentação e aumenta a produção de nitrogênio amoniacal de grãos de milho e sorgo, mas não afeta a digestibilidade in vitro da matéria seca ou a produção de ácidos graxos de cadeia curta.

Abstract The grass Panicum maximum cv. BRS Tamani is a hybrid high-quality, small-sized forage plant with intense tillering activity. This study was carried out to examine the potential of the grass Panicum maximum cv. BRS Tamani at different regrowth ages (49, 63, 77, and 91 d) for hay production, in the rainy period. The experiment was conducted at the Farm School of the Federal University of Mato Grosso do Sul-Brazil, between October 2015 and April 2016. The treatments corresponded to four regrowth ages, with four replicates, distributed into 9 m2 plots. Regrowth ages influenced the morphogenetic characteristics of the grass, except for leaf senescence and final leaf length. Green (9.6-17.6 t ha-1) and dry-matter (2.6-5.9 t ha-1) yields, hay yield (3.4-6.9 t ha-1), and proportions of stem (91.6-455.9 g kg-1) and senescent material (34.8-98.4 g kg-1) increased with the regrowth ages, while the proportion of leaves (837.7-402.1 g kg-1) and the leaf: stem ratio (15.9-0.9) decreased (P<0.05). The dry matter (881.7-852.8 g kg-1) and protein contents (81.2-47.6 g kg-1) of the hay decreased with the higher regrowth ages; however, the neutral detergent fibre (746.5-759.2 g kg-1) acid detergent fibre (519.8-567.7 g kg-1) and lignin (74.3-86.4 g kg-1) contents rose as the regrowth ages did. Nutrient digestibility decreased with the regrowth ages (P<0.05). Panicum maximum cv. BRS Tamani has the potential to produce of hay ha-1, better nutritive value and a high proportion of leaves in the regrowth interval of 49 to 63 d.

Resumen El pasto Panicum maximum cv. BRS Tamani es una planta forrajera híbrida de alta calidad, de tamaño pequeño y con intensa actividad de macollaje. Este estudio se llevó a cabo para examinar el potencial del pasto Panicum maximum cv. BRS Tamani en diferentes edades de rebrote (49, 63, 77 y 91 días) para la producción de heno, en el período lluvioso. El experimento se realizó en la Escuela Agrícola de la Universidad Federal de Mato Grosso do Sul-Brasil, entre octubre de 2015 y abril de 2016. Los tratamientos correspondieron a cuatro edades de rebrote, con cuatro repeticiones, distribuidas en parcelas de 9 m2. Las edades de rebrote influyeron en las características morfogenéticas del pasto, excepto por la senescencia de la hoja y la longitud final de la hoja. Los rendimientos de materia verde (9.6-17.6 t ha-1) y seca (2.6-5.9 t ha-1), el rendimiento de heno (3.4-6.9 t ha-1) y las proporciones de tallo (91.6-455.9 g kg-1) y material senescente (34.8-98.4 g kg-1) aumentaron con las edades de rebrote, mientras que la proporción de hojas (837.7-402.1 g kg-1) y la relación hoja:tallo (15.9-0.9) disminuyeron (P<0.05). Los contenidos de materia seca (881.7-852.8 g kg-1) y de proteína (81.2-47.6 g kg-1) del heno disminuyeron con las mayores edades de rebrote; sin embargo, los contenidos de fibra detergente neutro (746.5-759.2 g kg-1), fibra detergente ácido (519.8-567.7 g kg-1) y lignina (74.3-86.4 g kg-1) aumentaron a medida que lo hicieron las edades de rebrote. La digestibilidad de los nutrientes disminuyó con las edades de rebrote (P<0.05). Panicum maximum cv. BRS Tamani tiene el potencial de producir heno ha-1, mejor valor nutritivo y una alta proporción de hojas en el intervalo de rebrote de 49 a 63 días.

Abstract The effect of the addition of xoconostle on in vitro ruminal fermentation of corn stover was determined in order to reduce methane emission. Previous studies have shown that xoconostle contains bioactive compounds with potential antimicrobial activity that enhance ruminal fermentation. Zero point zero percent, 2.0 %, 4.0 % and 6.0 % of xoconostle were added. The following were determined: chemical composition of the substrates, phenolic compounds, antioxidant capacity, in vitro disappearance of dry matter (IVDDM), the production of volatile fatty acids (VFAs) and the kinetic variables of gas production. The volume of methane was measured using the technique of capturing carbon dioxide in sodium hydroxide solution. The content of protein, ether extract, total phenols and antioxidant activity significantly increased (P<0.05) with the addition of xoconostle. The IVDDM also increased with the addition of xoconostle. Regarding the production of propionic acid, it increased significantly (P<0.05) with 6.0 % of xoconostle. The kinetic parameters obtained by the best fit of the experimental data showed a higher digestion rate and lower methane production with the addition of 4.0 and 6.0 % of xoconostle. The use of xoconostle as an additive in ruminant diets decreases methane production in vitro so it can be an alternative to mitigate the increase in the greenhouse effect and benefit the cultivation of a commercially not very appreciated fruit.

Resumen Se determinó el efecto de la adición de xoconostle en la fermentación ruminal in vitro de rastrojo de maíz con objeto de reducir la emisión de metano. Estudios previos han demostrado que el xoconostle contiene compuestos bioactivos con actividad antimicrobiana potencial que mejoran la fermentación ruminal. Se adicionaron el 0.0%, 2.0%, 4.0% y 6.0% de xoconostle. Se determinó la composición química de los sustratos, compuestos fenólicos, capacidad antioxidante, desaparición in vitro de la materia seca (DIVMS), la producción de ácidos grasos volátiles (AGV) y las variables de cinética de producción de gas. El volumen de metano se midió utilizando la técnica de captura de bióxido de carbono en solución de hidróxido de sodio. Con la adición del xoconostle se incrementó significativamente (P<0.05) el contenido de proteína, extracto etéreo, fenoles totales y actividad antioxidante. La DIVMS también se incrementó con la adición del xoconostle. Respecto a la producción de ácido propiónico, ésta se incrementó significativamente (P<0.05) con el 6.0 % de xoconostle. Los parámetros cinéticos obtenidos mediante el mejor ajuste de los datos experimentales mostraron una mayor tasa de digestión y menor producción de metano con la adición del 4.0 y 6.0 % de xoconostle. El uso de xoconostle como aditivo en dietas para rumiantes disminuye la producción de metano in vitro por lo que puede ser una alternativa para mitigar el incremento del efecto invernadero y beneficiar el cultivo de un fruto comercialmente no muy apreciado.

Abstract This study aimed to determine the concentration of CP, EE, NSC, fibers, TPC, CT, CBD, THC, in vitro digestibility of dry matter and rumen fermentation parameters of agroindustrial residues of Cannabis sativa L. from two extractive processes of cannabinoids, as a potential source of forage in ruminants feeding. The flower of Cannabis sativa was exposed to cold-press extraction (CPC) and alcoholic extraction (AEC) process; vegetative residues obtained after extractions were compared to raw flower as a control (RFC) using a completely randomized design and Tukey’s test for means comparison. Extractive processes decreased EE, TPC and cannabinoids (CBD and THC). Otherwise, fibers, NSC and digestibility, increased after the extractive processes in CPC and AEC. Similarly, in vitro degradability increased after both extractive processes above 120 % as well as latency period. Additionally, protozoa increased with CPC but no changes were observed in AEC. Likewise, no changes were observed in cellulolytic bacteria in CPC and AEC. However, total bacteria were reduced after both extractions. Moreover, N-ammonia in ruminal fermentations decreased with CPC and AEC whereas total volatile fatty acids increased. In addition, gas production increased above 75 % in CPC and AEC; however, no changes were observed in latency period. Furthermore, methane and CO2 production increased above 80 and 60 %, respectively for CPC and AEC; these augmentations are positively associated with improvements in the ruminal fermentations. In conclusions, the agroindustrial residue of Cannabis sativa L. obtained after the analyzed extractive processes may arise as a potential forage source in ruminants feeding.

Resumen Este estudio tuvo como objetivo determinar la concentración de PC, EE, CNS, fibras, CFT, TC, CBD, THC, digestibilidad in vitro de materia seca y parámetros de fermentación ruminal de residuos agroindustriales de Cannabis sativa L. de dos procesos extractivos de cannabinoides, como fuente potencial de forraje en la alimentación de rumiantes. La flor de Cannabis sativa se expuso al proceso de extracción por prensado en frío (CPF) y extracción alcohólica (CEA); los residuos vegetativos obtenidos después de las extracciones se compararon con la flor cruda como testigo (FCC) utilizando un diseño completamente al azar y la prueba de Tukey para la comparación de medias. Los procesos extractivos disminuyeron el EE, CFT y cannabinoides (CBD y THC). En contraste, las fibras, CNS y digestibilidad, aumentaron después de los procesos extractivos en CPF y CEA. Del mismo modo, la degradabilidad in vitro aumentó después de ambos procesos extractivos por encima del 120 %, así como el período de latencia. Además, los protozoos aumentaron con CPF, pero no se observaron cambios en CEA. Asimismo, no se observaron cambios en las bacterias celulolíticas en CPF y CEA. Sin embargo, las bacterias totales se redujeron después de ambas extracciones. Además, el N-amoníaco en las fermentaciones ruminales disminuyó con CPF y CEA, mientras que los ácidos grasos volátiles totales aumentaron. Además, la producción de gas aumentó por encima del 75 % en CPF y CEA; sin embargo, no se observaron cambios en el período de latencia. Además, la producción de metano y CO2 aumentó por encima del 80 y 60 %, respectivamente, para CPF y CEA; estos aumentos se asocian positivamente con mejoras en las fermentaciones ruminales. En conclusión, el residuo agroindustrial de Cannabis sativa L. obtenido después de los procesos extractivos analizados puede surgir como una fuente potencial de forraje en la alimentación de rumiantes.

Abstract The objective was to compare the effects of sodium selenite (SS) and Sel-Plex® (SP) on dry matter intake (DMI), daily weight gain (DWG), feed conversion (FC), carcass yield, Se in serum, muscle, albumin, and globulins in Pelibuey lambs. Fifty (50) animals (LW=23.0 ± 1.1 kg; 5 to 6 mo) were stratified and randomly assigned to one of five treatments (n=10): 1) Basal diet, C); 2) C + 0.30 mg kg-1 DM of SS, 30SS; 3) C + 0.90 mg kg-1 DM of SS, 90SS; 4) C + 0.30 mg kg-1 DM of SP, 30SP; and 5) C + 0.90 mg kg-1 DM of SP, 90SP. There was no effect (P>0.05) on DMI; while 90SP and 30SS showed higher DWGs (293 and 260 vs 245, 243, and 230 g d-1; P<0.05) compared to the other treatments. FC was better for 90SP and C. Final LWs, carcass yields and dorsal fat were not affected (P>0.05). In the Longissimus dorsi, 30SP increased (P<0.05) Se with respect to 90SP and C and was similar with 30SS and 90SS. There was no effect (P>0.05) on the Gluteus maximus and Musculus deltoideus. Albumin was higher with 30SP and 90SS; while α-globulin was higher with 30SS and 90SP. In conclusion, 0.90 mg of SP improved DWG and FC. Selenite and SP increased Se in serum up to 0.30, and it decreased with 0.90 mg per kilogram of SP. In the Longissimus dorsi, Se was improved in 30SP with respect to 90SP and C and was not similar to 90SS and 30SS. The organic Se of 90SP improved the level of albumin and α-globulins.

Resumen El objetivo fue comparar los efectos de selenito de sodio (SS) y Sel-Plex® (SP) en el consumo de materia seca (CMS), ganancia diaria de peso (GDP), conversión alimenticia (CA), rendimiento de canales, Se en suero, músculos, albúmina, y globulinas en corderos Pelibuey. Cincuenta animales (PV=23.0 ± 1.1 kg; de 5 a 6 meses) se estratificaron y aleatoriamente asignaron a uno de cinco tratamientos (n=10): 1) Dieta basal, C); 2) C + 0.30 mg kg-1 MS de SS, 30SS; 3) C + 0.90 mg kg-1 MS de SS, 90SS; 4) C + 0.30 mg kg-1 MS de SP, 30SP; y 5) C + 0.90 mg kg-1 MS de SP, 90SP. No hubo efectos (P>0.05) en CMS; mientras que 90SP y 30SS mostraron GDP mayores (293 y 260 vs 245, 243, y 230 g día-1; P<0.05) en comparación con los demás tratamientos. La CA fue mejor para 90SP y C. Los PV finales, rendimientos de canales y la grasa dorsal no se afectaron (P>0.05). En Longissimus dorsi, 30SP incrementó (P<0.05) el Se con respecto a 90SP y C, y fue similar con 30SS y 90SS. No hubo efecto (P>0.05) en Gluteus maximus y Musculus deltoideus. La albúmina fue mayor con 30SP y 90SS; mientras que α-globulina fue mayor con 30SS y 90SP. En conclusión, 0.90 mg de SP mejoró la GDP y CA. Selenito y SP aumentaron el Se en suero hasta 0.30, y disminuyó con 0.90 mg por kilo de SP. En Longissimus dorsi, el Se se mejoró en 30SP con respecto 90SP y el C y no fue similar a 90SS y 30SS. El Se orgánico de 90SP mejoró el nivel de albúmina y α-globulinas.

RESUMO A aplicação de silício (Si) representa uma das alternativas que podem ser utilizadas para mitigar os efeitos deletérios às plantas pela salinidade em cultivo fertirrigado. Objetivou-se avaliar o efeito de diferentes níveis de salinidade da água, associado ao uso de silicato de sódio sobre os parâmetros produtivos e os teores de nutrientes na folha e no caule da mini melancia em ambiente protegido. Para condução do experimento adotou-se delineamento em blocos casualizados, em esquema fatorial 6 x 2, com 4 repetições, sendo seis níveis de salinidade da água de irrigação (1,05; 2,12; 3,26; 4,41; 5,91 e 7,32 dS m-1) e dois tipos de aplicações de silício: sem silício e aplicação em solução via foliar. Foram avaliados: a altura das plantas, diâmetro do caule, número de folhas, peso da matéria fresca e seca de folhas e caule; variáveis biométricas e teor de sólidos solúveis totais nos frutos; e teor de nutrientes nas folhas e caule. O uso do silício associado a fertirrigação com diferentes níveis de salinidade proporcionaram resposta positiva para espessura de casca, ºBrix, massa fresca e seca de folhas e, acúmulo de silício nas folhas e caule. A salinidade isolada proporcionou aumento para peso de polpa, ºBrix dos frutos e teor de potássio no caule e, incrementou o teor de manganês e inibiu teor de zinco nas folhas. Houve interação significativa para o teor de manganês no caule, com resposta positiva na ausência de silício foliar e negativa com aplicação foliar de silício sob diferentes níveis de salinidade.

ABSTRACT The application of silicon (Si) represents one of the alternatives that can be used to mitigate the deleterious effects caused by salinity on plants in fertigated cultivation. The objective was to evaluate the effect of different levels of water salinity, associated with the use of sodium silicate on the production parameters and nutrient levels in the leaf and stem of mini watermelon in a protected environment. To conduct the experiment, a randomized block design was adopted, in a 6 x 2 factorial scheme, with 4 repetitions, with six levels of irrigation water salinity (1.05; 2.12; 3.26; 4.41; 5.91 and 7.32 dS m-1) and two types of Si application: without Si and in foliar solution. The following parameters were evaluated: plant height, stem diameter, number of leaves, leaf and stem fresh and dry mass; biometric variables and total soluble solids content in the fruits; and nutrient contents in leaves and stem. The use of Si associated with fertigation with different salinity levels promoted a positive response for peel thickness, ºBrix, fresh and dry mass of leaves, and Si accumulation in leaves and stem. Salinity alone promoted an increase in pulp weight, ºBrix of the fruits and potassium content in the stem, besides increasing the manganese content and inhibiting the zinc content in the leaves. There was a significant interaction for the manganese content in the stem, with a positive response in the absence of foliar-applied Si and a negative response in the presence of foliar-applied Si under different levels of salinity.

RESUMEN La yuca (Manihot esculenta Crantz) es uno de los principales alimentos utilizado como fuente de energía, proporciona el alimento básico para alimentar a más de 800 millones de personas en todo el mundo. En algunos países y zonas colombianas productoras de yuca el aumento en la producción ha disminuido, debido a que no se cuenta con la tecnología y conocimiento suficiente para contribuir a la demanda actual de yuca. El objetivo de este estudio fue evaluar el efecto del ácido 1-naftalenacético sobre algunas variables de rendimiento de yuca variedad MCol 2066 (chirosa). Se estableció un cultivo homogéneo de yuca y se obtuvieron esquejes de 15 cm de longitud, los cuales se sometieron a tres tiempos de inmersión (5, 10 y 20 min) en cuatro concentraciones de ácido 1-naftalenacético (0, 100, 200 y 300 ppm). Los datos se colectaron a los 240 días después de la siembra. Las variables evaluadas porcentaje de almidón, materia seca, y masa fresca de raíces, presentaron diferencias significativas entre tratamientos. Los valores más altos se observaron en el tratamiento a 20 min de inmersión en 200 ppm de ácido 1-naftalenacético para las variables, almidón (45,56 %), materia seca (51,6 %), y masa fresca (73,270 kg/ha). A las condiciones del estudio, este tratamiento fue el mejor inductor para aumentar el rendimiento del cultivo, debido a que influyó positivamente, mostrando mejores resultados en las variables porcentaje de almidón, materia seca y masa fresca de la raíz, lo cual podría ser favorable para mejorar el rendimiento del cultivo de yuca variedad MCol 2066 (chirosa) en la región.

ABSTRACT Cassava (Manihot esculenta Crantz) is one of the main foods used as an energy source that is also as one of the staples feeding more than 800 million people worldwide. In some countries as well as some Colombian areas known for their cassava production, there has been a decrease in their production growth due to the fact that there is neither enough technology nor knowledge to contribute to the current demand for cassava. The objective of this study was to evaluate the effect of 1-naphthaleneacetic acid on some yield-related variables on variety MCol 2066 of cassava (chirosa). A homogeneous crop of cassava was established and cuttings of 15 cm in length were obtained, which in turn were subjected to three immersion times (5, 10 and 20 min) in four concentrations of 1-naphthaleneacetic acid (0, 100, 200 and 300 ppm). Data were collected 240 days after planting. The evaluated variables which were percentage of starch, dry matter, and fresh root mass, showed significant differences between treatments. The highest values were observed in the treatment at 20 min immersion in 200 ppm of 1-naphthaleneacetic acid for the variables, starch (45,56 %), dry matter (51,6 %), and fresh mass (73.270 kg/ha). Under the conditions of the study, this treatment was the best inducer to increase the yield of the crop, because it influenced positively on such results, showing better results in the variables percentage of starch, dry matter and fresh mass of the root, which could be favorable to improve the yield of the crop of variety MCol 2066 cassava (chirosa) in the region.