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Montane cloud forests are highly threatened ecosystems that are vulnerable to climate change. These complex habitats harbor many species that suffer the negative consequences of this global phenomenon, such as shifts in their distribution and habitat use. The Central American clouded oncilla (Leopardus pardinoides oncilla) is the smallest and most endangered wild cat in Mesoamerica and is primarily reported in cloud forests throughout its distribution. The species is poorly understood, with no studies conducted in Central America assessing its habitat preferences. To bridge this knowledge gap, we sampled two mountain ranges in Costa Rica with camera traps and conducted an occupancy analysis to understand the anthropogenic and environmental features that influence oncilla habitat use within them. Additionally, we conducted spatial predictions of habitat use across its northern and southern range in Costa Rica to identify priority conservation areas for the species. We found that Central American clouded oncilla habitat use is driven primarily by environmental factors. Our results showed that oncillas select habitats with denser tree cover at high elevations, closer to permanent water sources, which may provide them with high prey density and a favorable habitat structure for their survival. Spatial predictions identified two main regions as conservation priority areas where threat mitigation efforts and monitoring should be implemented: the Caribbean slope of the Talamanca mountains, and the Arenal-Monteverde forest complex. The occupancy modeling approach turned out to be very useful to assess the spatial associations of the species with the environment and mapping the conservation priority areas. Future research and mitigation actions should focus on potential threats that could negatively impact Central American clouded oncilla populations and habitat use, including the role of mesopredators and feral species.

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In plant tissue culture, differences in endogenous levels of species-specific plant growth regulators (PGRs) may explain differences in regenerative capacity. In the case of polyamines (PAs), their dynamics and distribution may vary between species, genotypes, tissues, and developmental pathways, such as sexual reproduction and apomixis. In this study, for the first time, we aimed to assess the impact of varying endogenous PAs levels in seeds from distinct reproductive modes in Miconia spp. (Melastomataceae), on their in vitro regenerative capacity. We quantified the free PAs endogenous content in seeds of Miconia australis (obligate apomictic), Miconia hyemalis (facultative apomictic), and Miconia sellowiana (sexual) and evaluated their in vitro regenerative potential in WPM culture medium supplemented with a combination of 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP). The morphogenic responses were characterized by light microscopy and scanning electron microscopy and discussed regarding the endogenous PAs profiles found. Seeds of M. sellowiana presented approximately eight times more putrescine than M. australis, which was associated with a higher percentage of regenerated calluses (76.67%) than M. australis (5.56%). On the other hand, spermine levels were significantly higher in M. australis. Spermine is indicated as an inhibitor of auxin-carrying gene expression, which may have contributed to its lower regenerative capacity under the tested conditions. These findings provide important insights into in vitro morphogenesis mechanisms in Miconia and highlight the significance of endogenous PA levels in plant regeneration. These discoveries can potentially optimize future regeneration protocols in Miconia, a plant group still underexplored in this area.

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Recently, the tiger-cat species complex was split into Leopardus tigrinus and Leopardus guttulus, along with other proposed schemes. We performed a detailed analysis integrating ecological modeling, biogeography, and phenotype of the four originally recognized subspecies-tigrinus, oncilla, pardinoides, guttulus-and presented a new multidimensional niche depiction of the species. Species distribution models used > 1400 records from museums and photographs, all checked for species accuracy. Morphological data were obtained from institutional/personal archives. Spotting patterns were established by integrating museum and photographic/camera-trap records. Principal component analysis showed three clearly distinct groups, with the Central American specimens (oncilla) clustering entirely within those of the Andes, namely the pardinoides group of the cloud forests of the southern Central-American and Andean mountain chains (clouded tiger-cat); the tigrinus group of the savannas of the Guiana Shield and central/northeastern Brazil (savanna tiger-cat); and the guttulus group in the lowland forests of the Atlantic Forest domain (Atlantic Forest tiger-cat). This scheme is supported by recent genetic analyses. All species displayed different spotting patterns, with some significant differences in body measurements/proportions. The new distribution presented alarming reductions from the historic range of - 50.4% to - 68.2%. This multidimensional approach revealed a new species of the elusive and threatened tiger-cat complex.

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Age affects the production of secondary metabolites, but how developmental cues regulate secondary metabolism remains poorly understood. The achiote tree (Bixa orellana L.) is a source of bixin, an apocarotenoid used in diverse industries worldwide. Understanding how age-dependent mechanisms control bixin biosynthesis is of great interest for plant biology and for economic reasons. Here we overexpressed miRNA156 (miR156) in B. orellana to comprehensively study the effects of the miR156-SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) module on age-dependent bixin biosynthesis in leaves. Overexpression of miR156 in annatto plants (miR156ox) reduced BoSPL transcript levels, impacted leaf ontogeny, lessened bixin production, and increased abscisic acid levels. Modulation of expression of BoCCD4-4 and BoCCD1, key genes in carotenoid biosynthesis, was associated with diverting the carbon flux from bixin to abscisic acid in miR156ox leaves. Proteomic analyses revealed an overall low accumulation of most secondary metabolite-related enzymes in miR156ox leaves, suggesting that miR156-targeted BoSPLs may be required to activate several secondary metabolic pathways. Our findings suggest that the conserved BomiR156-BoSPL module is deployed to regulate leaf dynamics of bixin biosynthesis, and may create novel opportunities to fine-tune bixin output in B. orellana breeding programs.

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The aim was to evaluate the effect of particle size and hay quality on feed intake, granulometric profile, and composition of the ruminoreticulum content in goats. We used 54 Alpine bucks in a completely randomized design with a factorial arrangement of 3 × 3. Treatments were a combination of Bermuda grass hay (Cynodon dactylon) with three quality levels: high (35 days), medium (50 days), and low (65 d) harvested at regrowth times. Were evaluated three particle sizes: small (16% ≥4.76 mm), medium (48% ≥4.76 mm), and large (75% ≥4.76 mm), which accounted for 66%, 75%, and 94% of physically effective fiber, respectively. Samples of offered diet, intake, and ruminoreticulum content were used to generate the granulometric profile. The offered diet, intake, and ruminoreticulum content presented different granulometric profiles regarding hay quality and particle size. Dry matter intake (DMI) and neutral detergent fiber intake (NDFI) increased (P < 0.05) when low-quality hay and large particles were offered. However, when particle size in low-quality hay was reduced, DMI and NDF decreased (P < 0.05). When analyzing the ruminoreticulum content (DM, NDF, peNDF, and indigestible DM), we did not observe any effect (P > 0.05) of hay quality or particle size on the variables. Thus, reducing hay quality and increasing particle size increase dry matter and fiber intake, presenting an interaction between forage quality and particle size. Forage quality and particle size promote intense selective behavior and chewing, which leads to a homogeneous content of particle profile in ruminoreticulum and a uniform average retention time.

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Mesocarnivores play a key role in ecosystem dynamics through the regulation of prey populations and are sensitive to environmental changes; thus, they are often considered good model organisms for conservation planning. However, data regarding the factors that influence the habitat use of threatened small wild felids such as the Andean tiger cat (Leopardus tigrinus pardinoides) are scarce. We conducted a two-year survey with 58 camera trap stations to evaluate the determinants of Andean tiger cat habitat use in three protected areas in the Middle Cauca, Colombia. We developed site occupancy models and found that Andean tiger cat habitat use increased with leaf litter depth at intermediate elevations and far from human settlements. Through conditional cooccurrence models, we found that Andean tiger cat habitat use was invariant to the presence of prey or potential intraguild competitors and killers/predators, but its detectability increased when they were present and detected. This suggests that Andean tiger cats may be more likely to be detected in sites with high prey availability. We found that Andean tiger cats preferred sites with deep leaf litter, which is a particular feature of cloud forests that provides suitable conditions for ambush hunting and hiding from intraguild enemies. Our results showed that Andean tiger cats avoided human settlements, which may minimize potential mortality risks in those areas. Moreover, the restricted use of middle elevations by Andean tiger cats suggested that they could be used as a sentinel species to track the effects of climate change since their suitable habitat is likely to be projected upward in elevation. Future conservation actions must be focused on identifying and mitigating human-related threats close to the Andean tiger cat habitat while preserving microhabitat conditions and the existing networks of protected areas.

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The semi-arid Caatinga is the largest dry forest ecoregion in the Americas; nevertheless, it is experiencing alarming rates of habitat loss. Most vegetation fragments in the biome are either unprotected or within private lands; however, these private areas are susceptible to anthropogenic activity, and often have the presence of non-native wildlife such as domestic dogs and cats. Two small felid species, the northern tiger cat and the jaguarundi co-occur throughout the Caatinga and have overlapping niches, which require segregation mechanisms to avoid interference competition. Assessing these species strategies for coexistence is crucial, as it can guide conservation actions. With this aim, a private ranch in the Brazilian Caatinga drylands was surveyed and multi-species occupancy models were used to assess co-occurrence patterns between northern tiger cats and jaguarundis. The degree of temporal overlap between both felids and domestic dogs and cats were also assessed. Evidence was found of positive co-occurrence between tiger cats and jaguarundis, suggesting a lack of spatial segregation at our study site; and low temporal overlap was found between both felids, with tiger cats being nocturnal and jaguarundis diurnal. High temporal overlap was found though between domestic dogs and both wild felid species. Our results suggest that small felids can coexist in private areas of the Caatinga with sufficient habitat. However, there is a need to highlight the potential threat of disease transmission by non-native carnivores as something that should be addressed in these private landscapes.

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Several forest types compose the apparently homogenous forest landscape of the lowland Amazon. The seasonally flooded forests (igapós) of the narrow floodplains of the blackwater rivers of the Amazon basin support their community of animals; however, these animals are required to adapt to survive in this environment. Furthermore, several taxa are an important source of seasonal resources for the animals in the adjacent unflooded forest (terra firme). During the low-water phase, the igapó becomes available to terrestrial species that make use of terra firme and igapó forests. Nonetheless, these lateral movements of terrestrial mammals between hydrologically distinct forest types remain poorly understood. This study tested the hypothesis that the attributes of the assemblages (abundance, richness, evenness, and functional groups) of the terrestrial mammals in both these forest types of the Cuieiras River basin, which is located in the Central Amazon, are distinct and arise from the ecological heterogeneity induced by seasonal floods. After a sampling effort of 10,743 camera trap days over four campaigns, two for the terra firme (6,013 trap days) and two for the igapó forests (4,730 trap days), a total of 31 mammal species (five were considered eventual) were recorded in both forest types. The species richness was similar in the igapó and terra firme forests, and the species abundance and biomass were greater in the terra firme forest, which were probably due to its higher primary productivity; whereas the evenness was increased in the igapós when compared to the terra firme forest. Although both forest types shared 84% of the species, generally a marked difference was observed in the composition of the terrestrial mammal species. These differences were associated with abundances of some specific functional groups, i.e., frugivores/granivores. Within-group variation was explained by balanced variation in abundance and turnover, which the individuals of a given species at one site were substituted by an equivalent number of individuals of a different species at another site. However, the occupancy was similar between both forest types for some groups such as carnivores. These findings indicate that seasonal flooding is a relevant factor in structuring the composition of terrestrial mammal assemblages between terra firme and floodplain forests, even in nutrient-poor habitats such as igapós. The results also highlight the importance of maintaining the mosaic of natural habitats on the scale of the entire landscape, with major drainage basins representing management units that provide sufficiently large areas to support a range of ecological processes (e.g., nutrient transport, lateral movements and the persistence of apex predators).

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Amazonian mammal diversity is exceptionally high, yet new taxonomic discoveries continue to be made and many questions remain for understanding its diversification through time and space. Here we investigate the diversification of spiny rats in the genus Makalata, whose species are strongly associated with seasonally flooded forests, watercourses and flooded islands. We use a biogeographical approach based on a mitochondrial cytochrome b gene through divergence time estimation and reconstruction of ancestral areas and events. Our findings indicate an ancient origin of Makalata for the Guiana Shield and Eastern Amazonia as ancestral area. A first cladogenetic event led to a phylogeographic break into two broader clades of Makalata through dispersal, implying a pattern of western/Eastern Amazonian clades coinciding with the Purus Arch (middle Miocene). Most of subclades we infer originated between the late Pliocene to the early Pleistocene, with few recent exceptions in the early Pliocene through dispersal and vicariant events. The hypothesis of rivers as dispersal barriers is not corroborated for Makalata, as expected for mammalian species associated with seasonally flooded environments. We identify two key events for the expansion and diversification of Makalata species: the presence of geologically stable areas in the Guiana and Brazilian shields and the transition from lacustrine conditions in western Amazonia (Acre system) to a river system, with the establishment of the Amazon River transcontinental system and its tributaries. Our results are congruent with older geological scenarios for the Amazon basin formation (Miocene), but we do not discard the influence of recent dynamics on some speciation events and, mainly, on phylogeographic structuring processes.

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Understanding the distribution patterns of threatened species is central to conservation. The Amazonian distribution of the northern tiger cat (N-tiger cat, Leopardus tigrinus) and its interspecific relationship with the ocelot, its potential intraguild killer, are intriguing. Here, we combined presence/absence records with species distribution models (SDMs) to determine N-tiger cat occurrence in the Amazon. We also modeled ocelot density from 46 published estimates. The N-tiger cat's presence in the Amazon was negatively influenced by ocelot density and net primary productivity and positively influenced by savannas and precipitation in the driest month. The best-fitting model predicted highly patchy N-tiger cat occurrence over an area of 236,238.67 km2, almost exclusively in savanna enclaves. Additionally, 312,348 camera trap-days at 49 sites in the Amazon revealed no N-tiger cats. The ocelot densities were significantly higher in areas with denser vegetation cover and warmer habitats, with predicted densities ≥ 0.6 ind/km2 throughout most of the biome. The lowest ocelot densities (≤ 0.06 ind/km2) were observed along the predicted range of N-tiger cats. Our findings highlight that the N-tiger cat's presence in the Amazon is restricted to savannas and highly influenced by ocelot density, emphasizing the importance of including species interactions in SDMs.

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The objective of this study was to nutritionally evaluate the use of pineapple crop waste silage in the feeding of growing bull in different planes of nutrition. We used eight non-castrated growing bull housed in individual covered pens, provided with free access to water and individual trough. Two balanced Latin squares conducted simultaneously were used. Treatments consisted of four planes of nutrition (L), formed by multiples of maintenance, i.e., L = ME/Mm; they were ME/Mm, ME/1.5Mm, ME/2Mm, and ME/2.7Mm. The intake of nutrients in diets was determined by the difference between the total mass of food offered and the mass of orts. To determine nutrient digestibility and nitrogen balance, total feces, and urine, collections were performed for seven consecutive days in each animal per period. The increase in planes of nutrition affected (P < 0.05) nutrient intake between L = 1 and L = 1.5. However, there was no effect nutrients intake to 1.5, 2, and 2.7. Nutrient digestibility was affected by the increase in planes of nutrition (P < 0.05), except for dCF (P = 0.0659). Digestible and metabolizable energies were affected (P < 0.05) by the increase in nutritional plans, as well as nitrogen balance. In conclusion, the pineapple crop waste silage presents itself as a good forage alternative for cattle diets, especially during forage shortage periods. Inclusion in the diet at 2.7 × the maintenance level does not compromise growing bull performance. However, the increases in planes of nutrition reduce the digestible energy contents of the diet.

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The pampas cat is a small felid that occurs in open habitats throughout much of South America. Previous studies have revealed intriguing patterns of morphological differentiation and genetic structure among its populations, as well as molecular evidence for hybridization with the closely related L. tigrinus. Here we report phylogeographic analyses encompassing most of its distribution (focusing particularly on Brazilian specimens, which had been poorly sampled in previous studies), using a novel dataset comprising 2,143 bp of the mitogenome, along with previously reported mtDNA sequences. Our data revealed strong population strutucture and supported a west-to-east colonization process in this species' history. We detected two population expansion events, one older (ca. 200 thousand years ago [kya]) in western South America and another more recent (ca. 60-50 kya) in eastern areas, coinciding with the expansion of savanna environments in Brazil. Analyses including L. tigrinus individuals bearing introgressed mtDNA from L. colocola showed a complete lack of shared haplotypes between species, indicating that their hybridization was ancient. Finally, we observed a close relationship between Brazilian/Uruguayan L. colocola haplotypes and those sampled in L. tigrinus, indicating that their hybridization was likely related to the demographic expansion of L. colocola into eastern South America.

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Abstract The pampas cat is a small felid that occurs in open habitats throughout much of South America. Previous studies have revealed intriguing patterns of morphological differentiation and genetic structure among its populations, as well as molecular evidence for hybridization with the closely related L. tigrinus. Here we report phylogeographic analyses encompassing most of its distribution (focusing particularly on Brazilian specimens, which had been poorly sampled in previous studies), using a novel dataset comprising 2,143 bp of the mitogenome, along with previously reported mtDNA sequences. Our data revealed strong population strutucture and supported a west-to-east colonization process in this species' history. We detected two population expansion events, one older (ca. 200 thousand years ago [kya]) in western South America and another more recent (ca. 60-50 kya) in eastern areas, coinciding with the expansion of savanna environments in Brazil. Analyses including L. tigrinus individuals bearing introgressed mtDNA from L. colocola showed a complete lack of shared haplotypes between species, indicating that their hybridization was ancient. Finally, we observed a close relationship between Brazilian/Uruguayan L. colocola haplotypes and those sampled in L. tigrinus, indicating that their hybridization was likely related to the demographic expansion of L. colocola into eastern South America.

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Although primate predation is rarely observed, a series of primate anti-predation strategies have been described. Energetic costs of such strategies can vary from high-cost mobbing, via less costly alarm calling, to low-cost furtive concealment. Here we report the anti-predation strategies of red-nosed cuxiú, Chiropotes albinasus, based on direct observations from four study sites in southeastern Brazilian Amazonia. Over a collective period of 1255 fieldwork hours, we observed nine direct interactions between raptors (all potential predators) and red-nosed cuxiús. Of these, one (11%) resulted in predation. Raptors involved were: Harpia harpyja (four events), Leucopternis sp. (two events), Spizaëtus tyrannus (one event), and unidentified large raptors (two events). Predation attempts occurred in flooded-forest and terra firme rainforest, were directed at both adult and non-adult cuxiús, and involved both adult and juvenile raptors. Anti-predation strategies adopted by the cuxiús included: (1) group defence and mobbing behaviour (two occasions), (2) dropping into dense sub-canopy (seven occasions), (3) alarm calling (eight occasions), and (4) fleeing to, and hiding in, dense vegetation (eight occasions). During each encounter at least two of these behaviours were recorded. These are the first published records of predation, predation attempts, and anti-predator behaviour involving red-nosed cuxiú.

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Vertebrates are a vital ecological component of Amazon forest biodiversity. Although vertebrates are a functionally important part of various ecosystem services they continue to be threatened by anthropogenic impacts throughout the Amazon. Here we use a standardized, regularly spaced arrangement of camera traps within 25km2 to provide a baseline assessment of vertebrate species diversity in a sustainable use protected area in the eastern Brazilian Amazon. We examined seasonal differences in the per species encounter rates (number of photos per camera trap and number of cameras with photos). Generalized linear models (GLMs) were then used to examine the influence of five variables (altitude, canopy cover, basal area, distance to nearest river and distance to nearest large river) on the number of photos per species and on functional groups. GLMs were also used to examine the relationships between large predators [Jaguar (Panthera onca) and Puma (Puma concolor)] and their prey. A total of 649 independent photos of 25 species were obtained from 1,800 camera trap days (900 each during wet and dry seasons). Only ungulates and rodents showed significant seasonal differences in the number of photos per camera. The number of photos differed between seasons for only three species (Mazama americana, Dasyprocta leporina and Myoprocta acouchy) all of which were photographed more (3 to 10 fold increase) during the wet season. Mazama americana was the only species where a significant difference was found in occupancy, with more photos in more cameras during the wet season. For most groups and species variation in the number of photos per camera was only explained weakly by the GLMs (deviance explained ranging from 10.3 to 54.4%). Terrestrial birds (Crax alector, Psophia crepitans and Tinamus major) and rodents (Cuniculus paca, Dasyprocta leporina and M. acouchy) were the notable exceptions, with our GLMs significantly explaining variation in the distribution of all species (deviance explained ranging from 21.0 to 54.5%). The group and species GLMs showed some novel ecological information from this relatively pristine area. We found no association between large cats and their potential prey. We also found that rodent and bird species were more often recorded closer to streams. As hunters gain access via rivers this finding suggests that there is currently little anthropogenic impact on the species. Our findings provide a standardized baseline for comparison with other sites and with which planned management and extractive activities can be evaluated.

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Hybridization among animal species has recently become more recognized as an important phenomenon, especially in the context of recent radiations. Here we show that complex hybridization has led to contrasting patterns of genomic composition among closely related species of the Neotropical cat genus Leopardus. We show strong evidence of ancient hybridization and introgression between the pampas cat (L. colocolo) and northeastern populations of tigrina (L. tigrinus), leading to remarkable cytonuclear discordance in the latter. In contrast, southern tigrina populations show recent and continuing hybridization with Geoffroy's cat (L. geoffroyi), leading to extreme levels of interspecific admixture at their contact zone. Finally, we demonstrate that two seemingly continuous Brazilian tigrina populations show no evidence of ongoing gene flow between them, leading us to support their formal recognition as distinct species, namely L. tigrinus in the northeast and L. guttulus in the south.

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The objectives of this work were to study the effect of chemical and organic fertilization on the forage dry matter chemical composition characteristics of elephant grass and to estimate the total net energy of forage and the total digestible nutrients. Two elephant grass stocking piles were formed and two fertilization systems were used. Soil and plant evaluations (chemical and physical analysis) were performed at field. Was carried out in a completely block (six periods) randomized design and three replicates per forage (chemical and organic fertilization) per block. Data of crude protein, neutral detergent fiber, and ashes, calcium, phosphorus, magnesium and potassium were evaluated by F test, at 5% of probability. Based on the total digestible nutrients contents, the total net energy and total digestible nutrients of the elephant grass from the two fertilization systems were estimated. The elephant grass submitted to fertilization organic showed higher chemical composition values. In this forage, higher contents of crude protein (17.26%), ashes (26%) and phosphorus (36.88%) and smaller of neutral detergent fiber (3,96%) were observed in relation to the elephant grass submitted to fertilization chemical. The application of cattle manure in elephant grass improved the organic matter content in soil, to improve the chemical composition, and provide greater flexibility in the

Objetivou-se avaliar os efeitos da adubação química e orgânica sobre a composição químico-bromatológica do capim elefante, além de estimar a energia líquida do volumoso e os nutrientes digestíveis totais desta forrageira. Foram formadas duas áreas de capineiras e utilizados dois sistemas de adubação. Utilizou-se delineamento em blocos (seis períodos), casualizados completos e três repetições por volumoso (adubação química e adubação orgânica) por bloco. Os dados de proteína bruta, fibra em detergente neutro, cinzas, cálcio, magnésio, potássio e fósforo foram avaliados pelo teste F, a 5% de probabilidade. Com base na fibra em detergente neutro, estimou-se a energia líquida do volumoso e os nutrientes digestíveis totais do capim-elefante nos dois sistemas de adubação. Com base nos resultados, observa-se que o capim-elefante submetido à adubação orgânica apresenta maiores valores em sua composição químico-bromatológica. Foram observados nesta forragem submetida à adubação orgânica, maiores teores de proteína bruta (17,26%), cinzas (26%) e fósforo (36,88%) e menores teores de fibra em detergente neutro (3,96%) em relação ao capim-elefante submetido à adubação química. A aplicação de esterco de curral na capineira de capim-elefante melhorou o teor de matéria orgânica no solo, o que propiciou melhoria na composição químico-bromatológica, além de proporcionar maior flexibilização na f

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The objectives of this work were to study the effect of chemical and organic fertilization on the forage dry matter chemical composition characteristics of elephant grass and to estimate the total net energy of forage and the total digestible nutrients. Two elephant grass stocking piles were formed and two fertilization systems were used. Soil and plant evaluations (chemical and physical analysis) were performed at field. Was carried out in a completely block (six periods) randomized design and three replicates per forage (chemical and organic fertilization) per block. Data of crude protein, neutral detergent fiber, and ashes, calcium, phosphorus, magnesium and potassium were evaluated by F test, at 5% of probability. Based on the total digestible nutrients contents, the total net energy and total digestible nutrients of the elephant grass from the two fertilization systems were estimated. The elephant grass submitted to fertilization organic showed higher chemical composition values. In this forage, higher contents of crude protein (17.26%), ashes (26%) and phosphorus (36.88%) and smaller of neutral detergent fiber (3,96%) were observed in relation to the elephant grass submitted to fertilization chemical. The application of cattle manure in elephant grass improved the organic matter content in soil, to improve the chemical composition, and provide greater flexibility in the

Objetivou-se avaliar os efeitos da adubação química e orgânica sobre a composição químico-bromatológica do capim elefante, além de estimar a energia líquida do volumoso e os nutrientes digestíveis totais desta forrageira. Foram formadas duas áreas de capineiras e utilizados dois sistemas de adubação. Utilizou-se delineamento em blocos (seis períodos), casualizados completos e três repetições por volumoso (adubação química e adubação orgânica) por bloco. Os dados de proteína bruta, fibra em detergente neutro, cinzas, cálcio, magnésio, potássio e fósforo foram avaliados pelo teste F, a 5% de probabilidade. Com base na fibra em detergente neutro, estimou-se a energia líquida do volumoso e os nutrientes digestíveis totais do capim-elefante nos dois sistemas de adubação. Com base nos resultados, observa-se que o capim-elefante submetido à adubação orgânica apresenta maiores valores em sua composição químico-bromatológica. Foram observados nesta forragem submetida à adubação orgânica, maiores teores de proteína bruta (17,26%), cinzas (26%) e fósforo (36,88%) e menores teores de fibra em detergente neutro (3,96%) em relação ao capim-elefante submetido à adubação química. A aplicação de esterco de curral na capineira de capim-elefante melhorou o teor de matéria orgânica no solo, o que propiciou melhoria na composição químico-bromatológica, além de proporcionar maior flexibilização na f

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It was evaluated the financial result of the confinement of Nelore bovines, subdued to different levels of substitution of sorghum silage by sugarcane or sugarcane bagasse ammoniated with urea. It were confined 35 young bulls with age average of 2 years, initial average weight of 448,2kg distributed in 7 treatments: 100% of sorghum silage; 70% of sorghum silage + 30% of sugarcane; 30% of sorghum silage + 70% of sugarcane; 100% of sugarcane; 70% of sorghum silage + 30% of sugarcane bagasse ammoniated with urea; 30% of sorghum silage + 70% of sugarcane bagasse ammoniated with urea and 100% of sugarcane bagasse ammoniated with urea. Concentrate was provided in the amount corresponding to 1.2% of body weight. It were analyzed the different components of the fodder used in the trial and the results of weight gain acquired, with final average weight of 512.3kg. The treatment with 100% of sorghum silage showed the best economic efficiency, followed by sugarcane and sugarcane ammoniated bagasse used alone, covering the total operational costs and showing positive residue. Different combinations of sorghum silage with sugarcane or with sugarcane ammoniated bagasse showed insufficient performance to cover the total variable costs. The treatment did not show economic efficiency to cover the total costs that include the opportunity costs.

Foram avaliados os resultados financeiros obtidos no confinamento de novilhos Nelore, submetidos a diferentes níveis de substituição de silagem de sorgo por cana-de-açúcar ou bagaço de cana amonizado com ureia. Foram confinados 35 animais machos não castrados com idade média de 24 meses, peso médio inicial de 448,2kg, distribuídos em 7 tratamentos: 100% silagem de sorgo; 70% de silagem de sorgo + 30% de cana-de-açúcar; 30% de silagem de sorgo + 70% de cana-de-açúcar; 100% de cana-de-açúcar; 70% de silagem de sorgo + 30% de bagaço de cana amonizado com ureia; 30% de silagem de sorgo + 70% de bagaço de cana amonizado com ureia e 100% de bagaço de cana amonizado com ureia. O concentrado fornecido correspondeu a 1,2% do peso corporal. Para avaliação econômica dos resultados, foram analisados os diferentes componentes dos tratamentos utilizados no experimento e os resultados de ganho de peso obtidos, e o peso médio final foi de 512,3kg. O tratamento com 100% de silagem de sorgo apresentou a melhor eficiência econômica, seguido pela cana-de-açúcar e pelo bagaço de cana-de-açúcar amonizado usados isoladamente, com cobertura do total dos custos operacionais e apresentação do resíduo positivo. As diferentes combinações de silagem de sorgo e cana-de-açúcar e as de bagaço de cana-de-açúcar amonizado e silagem de sorgo apresentaram desempenho econômico insuficiente para cobrir os custos op

RESUMEN

It was evaluated the financial result of the confinement of Nelore bovines, subdued to different levels of substitution of sorghum silage by sugarcane or sugarcane bagasse ammoniated with urea. It were confined 35 young bulls with age average of 2 years, initial average weight of 448,2kg distributed in 7 treatments: 100% of sorghum silage; 70% of sorghum silage + 30% of sugarcane; 30% of sorghum silage + 70% of sugarcane; 100% of sugarcane; 70% of sorghum silage + 30% of sugarcane bagasse ammoniated with urea; 30% of sorghum silage + 70% of sugarcane bagasse ammoniated with urea and 100% of sugarcane bagasse ammoniated with urea. Concentrate was provided in the amount corresponding to 1.2% of body weight. It were analyzed the different components of the fodder used in the trial and the results of weight gain acquired, with final average weight of 512.3kg. The treatment with 100% of sorghum silage showed the best economic efficiency, followed by sugarcane and sugarcane ammoniated bagasse used alone, covering the total operational costs and showing positive residue. Different combinations of sorghum silage with sugarcane or with sugarcane ammoniated bagasse showed insufficient performance to cover the total variable costs. The treatment did not show economic efficiency to cover the total costs that include the opportunity costs.

Foram avaliados os resultados financeiros obtidos no confinamento de novilhos Nelore, submetidos a diferentes níveis de substituição de silagem de sorgo por cana-de-açúcar ou bagaço de cana amonizado com ureia. Foram confinados 35 animais machos não castrados com idade média de 24 meses, peso médio inicial de 448,2kg, distribuídos em 7 tratamentos: 100% silagem de sorgo; 70% de silagem de sorgo + 30% de cana-de-açúcar; 30% de silagem de sorgo + 70% de cana-de-açúcar; 100% de cana-de-açúcar; 70% de silagem de sorgo + 30% de bagaço de cana amonizado com ureia; 30% de silagem de sorgo + 70% de bagaço de cana amonizado com ureia e 100% de bagaço de cana amonizado com ureia. O concentrado fornecido correspondeu a 1,2% do peso corporal. Para avaliação econômica dos resultados, foram analisados os diferentes componentes dos tratamentos utilizados no experimento e os resultados de ganho de peso obtidos, e o peso médio final foi de 512,3kg. O tratamento com 100% de silagem de sorgo apresentou a melhor eficiência econômica, seguido pela cana-de-açúcar e pelo bagaço de cana-de-açúcar amonizado usados isoladamente, com cobertura do total dos custos operacionais e apresentação do resíduo positivo. As diferentes combinações de silagem de sorgo e cana-de-açúcar e as de bagaço de cana-de-açúcar amonizado e silagem de sorgo apresentaram desempenho econômico insuficiente para cobrir os custos op