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Beach volleyball (BV) is an intermittent sport characterised by short-duration and highly demanding activities with low intensity periods. Establishing if players' jump ability is influenced by sand granulometry is a useful information for sport scientists, coaches and players. This study aimed to assess the possible differences in the kinetics parameters of the vertical jump on different types of sand performed by BV players. Twelve elite female players performed six countermovement jumps (CMJs) in three different surface conditions (fine sand, reference, coarse sand) in a random counterbalanced order (216 jumps). A generalised mixed model approach detected differences for CMJ model in total duration (p: 0.016), eccentric phase duration (p: 0.007), concentric phase duration (p: 0.011), time to peak power (p: < 0.001), time to peak force (p: 0.014), maximum rate force development concentric phase (p: 0.004), maximum velocity (p: 0.028) and peak power eccentric (p: 0.018). Coarse sand decreases the time spent jumping compared to fine sand, without a penalty to jump height. Coaches and athletes should take this information into account to enhance their understanding of practice strategies and game conditions. One might anticipate a faster pace in games played on coarse sand and a slower pace on fine sand.

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Extracellular vesicles (EVs) hold promise as a source of disease biomarkers. The diverse molecular cargo of EVs can potentially indicate the status of their tissue of origin, even against the complex background of whole plasma. The main tools currently available for assessing biomarkers of brain health include brain imaging and analysis of the cerebrospinal fluid of patients. Given the costs and difficulties associated with these methods, isolation of EVs of neuronal origin (NEVs) from the blood is an attractive approach to identify brain-specific biomarkers. This perspective describes current key challenges in EV- and NEV-based biomarker research. These include the relative low abundance of EVs, the lack of validated isolation methods, and the difficult search for an adequate target for immunocapturing NEVs. We discuss that these challenges must be addressed before NEVs can fulfill their potential for biomarker research. HIGHLIGHTS: NEVs are promising sources of biomarkers for brain disorders. Immunocapturing NEVs from complex biofluids presents several challenges. The choice of surface target for capture will determine NEV yield. Contamination by non-EV sources is relevant for biomarkers at low concentrations.

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Investigating the evolutionary trajectory of synapsid sensory and cephalic systems is pivotal for understanding the emergence and diversification of mammals. Recent studies using CT-scanning to analyze the rostral foramina and maxillary canals morphology in fossilized specimens of probainognathian cynodonts have contributed to clarifying the homology and paleobiological interpretations of these structures. In the present work, µCT-scannings of three specimens of Riograndia guaibensis, an early Norian cynodont from southern Brazil, were analyzed and revealed an incomplete separation between the lacrimal and maxillary canals, with points of contact via non-ossified areas. While the maxillary canal exhibits a consistent morphological pattern with other Prozostrodontia, featuring three main branches along the lateral region of the snout, the rostral alveolar canal in Riograndia displays variability in the number of extra branches terminating in foramina on the lateral surface of the maxilla, showing differences among individuals and within the same skull. Additionally, pneumatization is observed in the anterior region of the skull, resembling similar structures found in reptiles and mammals. Through this pneumatization, certain branches originating from the maxillary canal extend to the canine alveolus. Further investigation is warranted to elucidate the functionality of this structure and its occurrence in other cynodont groups.

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To explore the diversity of scenarios in nature, animals have evolved tools to interact with different environmental conditions. Chemoreceptors are an important interface component and among them, olfactory receptors (ORs) and gustatory receptors (GRs) can be used to find food and detect healthy resources. Drosophila is a model organism in many scientific fields, in part due to the diversity of species and niches they occupy. The contrast between generalists and specialists Drosophila species provides an important model for studying the evolution of chemoreception. Here, we compare the repertoire of chemoreceptors of different species of Drosophila with that of D. incompta, a highly specialized species whose ecology is restricted to Cestrum flowers, after reporting the preferences of D. incompta to the odor of Cestrum flowers in olfactory tests. We found evidence that the chemoreceptor repertoire in D. incompta is smaller than that presented by species in the Sophophora subgenus. Similar patterns were found in other non-Sophophora species, suggesting the presence of underlying phylogenetic trends. Nevertheless, we also found autapomorphic gene losses and detected some genes that appear to be under positive selection in D. incompta, suggesting that the specific lifestyle of these flies may have shaped the evolution of individual genes in each of these gene families.

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The nasal cavity of living mammals is a unique structural complex among tetrapods, acquired along a series of major morphological transformations that occurred mainly during the Mesozoic Era, within the Synapsida clade. Particularly, non-mammaliaform cynodonts document several morphological changes in the skull, during the Triassic Period, that represent the first steps of the mammalian bauplan. We here explore the nasal cavity of five cynodont taxa, namely Thrinaxodon, Chiniquodon, Prozostrodon, Riograndia, and Brasilodon, in order to discuss the main changes within this skull region. We did not identify ossified turbinals in the nasal cavity of these taxa and if present, as non-ossified structures, they would not necessarily be associated with temperature control or the development of endothermy. We do, however, notice a complexification of the cartilage anchoring structures that divide the nasal cavity and separate it from the brain region in these forerunners of mammals.

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Body size influences most aspects of an animal's biology, consequently, evolutionary diversification is often accompanied by differentiation of body sizes within a lineage. It is accepted that miniaturization, or the evolution of extremely small body sizes, played a key role in the origin and early evolution of different mammalian characters in non-mammaliaform cynodonts. However, while there are multiple studies on the biomechanical, behavioral, and physiological consequences of smaller sizes, few explore the evolutionary processes that lead to them. Here, we use body mass as a universal size measurement in phylogenetic comparative analyses to explore aspects of body size evolution in Cynodontia, focusing on the cynodont-mammal transition, and test the miniaturization hypothesis for the origin of Mammaliaformes. We estimated the body masses of 29 species, ranging from Theriocephalia to Mammaliaformes, providing the largest collection of Triassic cynodont body mass estimates that we know of, and used these estimates in analyses of disparity through time and RRphylo . Unexpectedly, our results did not support the miniaturization hypothesis. Even though cynodont body size disparity fell during the Late Triassic, and remained lower than expected under a purely Brownian motion model of evolution up until the Early Jurassic, we found that rates of body size evolution were significantly lower in prozostrodontians leading to the first Mammaliaformes than in other lineages. Evolution rates were higher in medium and large-sized taxa, indicating that size was changing more rapidly in those lineages and that small sizes were probably a persistent plesiomorphic character-state in Cynodontia.

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Understanding the mechanisms that shape the architecture, diversity, and adaptations of genomes and their ecological and genetic interfaces is of utmost importance to understand biological evolution. Transposable elements (TEs) play an important role in genome evolution, due to their ability to transpose within and between genomes, providing sites of nonallelic recombination. Here we investigate patterns and processes of TE-driven genome evolution associated with niche diversification. Specifically, we compared TE content, TE landscapes, and frequency of horizontal transposon transfers (HTTs) across genomes of flower-breeding Drosophila (FBD) with different levels of specialization on flowers. Further, we investigated whether niche breadth and ecological and geographical overlaps are associated with a potential for HTT rates. Landscape analysis evidenced a general phylogenetic pattern, in which species of the D. bromeliae group presented L-shaped curves, indicating recent transposition bursts, whereas D. lutzii showed a bimodal pattern. The great frequency of highly similar sequences recovered for all FBD suggests that these species probably experienced similar ecological pressures and evolutionary histories that contributed to the diversification of their mobilomes. Likewise, the richness of TEs superfamilies also appears to be associated with ecological traits. Furthermore, the two more widespread species, the specialist D. incompta and the generalist D. lutzii, presented the highest frequency of HTT events. Our analyses also revealed that HTT opportunities are positively influenced by abiotic niche overlap but are not associated with phylogenetic relationships or niche breadth. This suggests the existence of intermediate vectors promoting HTTs between species that do not necessarily present overlapping biotic niches.

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Trained individuals may require variations in training stimuli and advanced resistance training paradigms (ADV) to increase skeletal muscle hypertrophy. However, no meta-analysis has examined how ADV versus traditional (TRAD) approaches may differentially affect hypertrophic outcomes in trained populations. The aim of this review was to determine whether the skeletal muscle hypertrophy responses induced by TRAD differed from ADV in resistance-trained individuals. Furthermore, we sought to examine potential effects of dietary factors, participants' training status, and training loads. We searched for peer-reviewed, randomized controlled trials (published in English) conducted in healthy resistance-trained adults performing a period of TRAD and ADV with pre-to-post measurement(s) of muscle hypertrophy in PubMed, Web of Science, SPORTDiscus, and MEDLINE databases up to October 2022. A formal meta-analysis was conducted in Revman5, and risk of bias was assessed by ROB2. Ten studies met the inclusion criteria. Results indicated no difference between ADV and TRAD for muscle thickness (SMD = 0.05, 95% CI: -0.20 0.29, p = 0.70), lean mass (SMD = -0.01, 95% CI: -0.26 0.23, p = 0.92), muscle cross-sectional area (SMD = -0.07, 95% CI: -0.36 0.22, p = 0.64), or all measurements analyzed together (SMD = -0.00, 95% CI: -0.15 0.14, p = 0.95). No heterogeneity or inconsistencies were observed; however, unclear risk of bias was present in most of the studies. Short-term ADV does not induce superior skeletal muscle hypertrophy responses when compared with TRAD in trained individuals. This review was not previously registered.

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This study was carried out with the objective of determining the antioxidant properties and quantification of total phenolics and flavonoids in relation to quercetin and rutin in some of the monofloral honeys produced in Minas Gerais (Brazil). In this study, 15 monofloral honey samples were obtained from different geographic regions of Minas Gerias, Brazil. The honeys were obtained from Cooperative of Beekeepers and Family Farmers of Northern Minas. To determine the antioxidant properties of honey samples, the test methods of total phenolic content, flavonoids (rutin and quercetin) and DPPH were used. As a result of the analysis of phenolic and flavonoid contents, the samples with the best results were A1-Aroeira and A4-Assa peixe. In antioxidant activity, the honey with the best EC50 results was A6-Aroeira. Differences between the antioxidant activities of the honey samples were found significantly (p< 0.01).

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In the last decades, several discoveries have uncovered the complexity of mammalian evolution during the Mesozoic Era, including important Gondwanan lineages: the australosphenidans, gondwanatherians, and meridiolestidans (Dryolestoidea). Most often, their presence and diversity is documented by isolated teeth and jaws. Here, we describe a new meridiolestidan mammal, Orretherium tzen gen. et sp. nov., from the Late Cretaceous of southern Chile, based on a partial jaw with five cheek teeth in locis and an isolated upper premolar. Phylogenetic analysis places Orretherium as the earliest divergence within Mesungulatidae, before other forms such as the Late Cretaceous Mesungulatum and Coloniatherium, and the early Paleocene Peligrotherium. The in loco tooth sequence (last two premolars and three molars) is the first recovered for a Cretaceous taxon in this family and suggests that reconstructed tooth sequences for other Mesozoic mesungulatids may include more than one species. Tooth eruption and replacement show that molar eruption in mesungulatids is heterochronically delayed with regard to basal dryolestoids, with therian-like simultaneous eruption of the last premolar and last molar. Meridiolestidans seem endemic to Patagonia, but given their diversity and abundance, and the similarity of vertebrate faunas in other regions of Gondwana, they may yet be discovered in other continents.

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Recently, the morphology and encephalization of the brain endocast of the Triassic non-mammaliaform probainognathian cynodont Riograndia guaibensis were studied. Here, we analyzed the brain endocast of an additional specimen of this species. The new endocast shows well-defined olfactory bulbs and a median sulcus dividing the hemispheres, traits that were not clearly observed in the first studied specimen. Encephalization quotients were also calculated, revealing similar values to other non-mammaliaform cynodonts and lower than those of the first analyzed specimen. The analyzed cranium is slightly larger than the first studied one and may represent an advanced ontogenetic stage. Hence, these differences may be related to the intraspecific variation of this cynodont or alternatively, to the preservation of each specimen.

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ABSTRACT: Macronutrient suppression is one way to identify which chemical elements is the most important in the early development of seedlings of forest species. This study evaluated the initial growth of Eucalyptus benthamii seedlings through morphological and physiological variables, submitted to doses of N, P and K, and liming. The experimental design to install the experiment was completely randomized, with a 2x9 factorial scheme, in which levels of factor "A" referred to absence and presence of liming and levels of factor "B", to the different treatments of NPK. Morphological variables of SD (stem diameter) and H (height) and the physiological variables of A (photosynthesis), E (transpiration), gs (stomatal conductance), Ci/Ca (relationship between intercellular and atmospheric CO2 concentration) and WUE (water use efficiency) were measured. For morphological variables, the absence of N directly affected the means and there was a direct relationship between increase of the dose and increase of SD and H. There was a positive relationship of P mainly in relation to shoot dry matter content (SDMC) and root dry matter content (RDMC). For the physiological variables, there was no direct response with the doses of N or P, with K being the element that most influenced the variables, especially when limestone was applied, resulting in higher averages for photosynthesis, transpiration and stomatal conductance. With the purpose of meeting the morphological and physiological demands, the recommendation for cultivation of Eucalyptus benthamii under the conditions of this study is the doses 150-200-150, without liming application.

RESUMO: A supressão dos macronutrientes é uma das maneiras de identificar qual ou quais dos elementos químicos é o mais importante no desenvolvimento inicial das mudas de espécies florestais. O estudo objetivou avaliar o crescimento inicial de mudas de Eucalyptus benthamii por meio de variáveis morfológicas e fisiológicas, submetidas a doses de N, P e K, e calagem. O delineamento experimental para instalação do experimento foi em delineamento inteiramente casualizado, com esquema fatorial 2x9, em que os níveis do fator "A" se referiram a ausência e a presença de calagem e os níveis do fator "B" aos diferentes tratamentos de NPK. Variáveis morfológicas de DAC (diâmetro a altura do colo) e H (altura) e as variáveis fisiológicas de A (fotossíntese), E (transpiração), gs (condutância estomática), Ci/Ca (relação entre a concentração intercelular e atmosférica de CO2) e WUE (eficiência no uso da água) foram determinadas. Para as variáveis morfológicas, a ausência do N afetou diretamente as médias, havendo uma relação direta entre o aumento da dose com o aumento das variáveis. Há uma relação positiva do P principalmente em relação a MSPA e MSPR. Para as variáveis fisiológicas, não houve resposta direta com as doses de N ou P, sendo o K o elemento que mais influenciou as variáveis, principalmente quando o calcário foi aplicado, resultando em maiores médias para fotossíntese, transpiração e condutância estomática. Com o objetivo de atender às demandas morfológicas e fisiológicas, a recomendação para o cultivo de Eucalyptus benthamii nas condições deste estudo é a dose 150-200-150, sem aplicação de calagem.

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Macronutrient suppression is one way to identify which chemical elements is the most important in the early development of seedlings of forest species. This study evaluated the initial growth of Eucalyptus benthamii seedlings through morphological and physiological variables, submitted to doses of N, P and K, and liming. The experimental design to install the experiment was completely randomized, with a 2x9 factorial scheme, in which levels of factor “A” referred to absence and presence of liming and levels of factor “B”, to the different treatments of NPK. Morphological variables of SD (stem diameter) and H (height) and the physiological variables of A (photosynthesis), E (transpiration), gs (stomatal conductance), Ci/Ca (relationship between intercellular and atmospheric CO2 concentration) and WUE (water use efficiency) were measured. For morphological variables, the absence of N directly affected the means and there was a direct relationship between increase of the dose and increase of SD and H. There was a positive relationship of P mainly in relation to shoot dry matter content (SDMC) and root dry matter content (RDMC). For the physiological variables, there was no direct response with the doses of N or P, with K being the element that most influenced the variables, especially when limestone was applied, resulting in higher averages for photosynthesis, transpiration and stomatal conductance. With the purpose of meeting the morphological and physiological demands, the recommendation for cultivation of Eucalyptus benthamii under the conditions of this study is the doses 150-200-150, without liming application.

A supressão dos macronutrientes é uma das maneiras de identificar qual ou quais dos elementos químicos é o mais importante no desenvolvimento inicial das mudas de espécies florestais. O estudo objetivou avaliar o crescimento inicial de mudas de Eucalyptus benthamii por meio de variáveis morfológicas e fisiológicas, submetidas a doses de N, P e K, e calagem. O delineamento experimental para instalação do experimento foi em delineamento inteiramente casualizado, com esquema fatorial 2x9, em que os níveis do fator “A” se referiram a ausência e a presença de calagem e os níveis do fator “B” aos diferentes tratamentos de NPK. Variáveis morfológicas de DAC (diâmetro a altura do colo) e H (altura) e as variáveis fisiológicas de A (fotossíntese), E (transpiração), gs (condutância estomática), Ci/Ca (relação entre a concentração intercelular e atmosférica de CO2) e WUE (eficiência no uso da água) foram determinadas. Para as variáveis morfológicas, a ausência do N afetou diretamente as médias, havendo uma relação direta entre o aumento da dose com o aumento das variáveis. Há uma relação positiva do P principalmente em relação a MSPA e MSPR. Para as variáveis fisiológicas, não houve resposta direta com as doses de N ou P, sendo o K o elemento que mais influenciou as variáveis, principalmente quando o calcário foi aplicado, resultando em maiores médias para fotossíntese, transpiração e condutância estomática. Com o objetivo de atender às demandas morfológicas e fisiológicas, a recomendação para o cultivo de Eucalyptus benthamii nas condições deste estudo é a dose 150-200-150, sem aplicação de calagem.

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Macronutrient suppression is one way to identify which chemical elements is the most important in the early development of seedlings of forest species. This study evaluated the initial growth of Eucalyptus benthamii seedlings through morphological and physiological variables, submitted to doses of N, P and K, and liming. The experimental design to install the experiment was completely randomized, with a 2x9 factorial scheme, in which levels of factor “A” referred to absence and presence of liming and levels of factor “B”, to the different treatments of NPK. Morphological variables of SD (stem diameter) and H (height) and the physiological variables of A (photosynthesis), E (transpiration), gs (stomatal conductance), Ci/Ca (relationship between intercellular and atmospheric CO2 concentration) and WUE (water use efficiency) were measured. For morphological variables, the absence of N directly affected the means and there was a direct relationship between increase of the dose and increase of SD and H. There was a positive relationship of P mainly in relation to shoot dry matter content (SDMC) and root dry matter content (RDMC). For the physiological variables, there was no direct response with the doses of N or P, with K being the element that most influenced the variables, especially when limestone was applied, resulting in higher averages for photosynthesis, transpiration and stomatal conductance. With the purpose of meeting the morphological and physiological demands, the recommendation for cultivation of Eucalyptus benthamii under the conditions of this study is the doses 150-200-150, without liming application.(AU)

A supressão dos macronutrientes é uma das maneiras de identificar qual ou quais dos elementos químicos é o mais importante no desenvolvimento inicial das mudas de espécies florestais. O estudo objetivou avaliar o crescimento inicial de mudas de Eucalyptus benthamii por meio de variáveis morfológicas e fisiológicas, submetidas a doses de N, P e K, e calagem. O delineamento experimental para instalação do experimento foi em delineamento inteiramente casualizado, com esquema fatorial 2x9, em que os níveis do fator “A” se referiram a ausência e a presença de calagem e os níveis do fator “B” aos diferentes tratamentos de NPK. Variáveis morfológicas de DAC (diâmetro a altura do colo) e H (altura) e as variáveis fisiológicas de A (fotossíntese), E (transpiração), gs (condutância estomática), Ci/Ca (relação entre a concentração intercelular e atmosférica de CO2) e WUE (eficiência no uso da água) foram determinadas. Para as variáveis morfológicas, a ausência do N afetou diretamente as médias, havendo uma relação direta entre o aumento da dose com o aumento das variáveis. Há uma relação positiva do P principalmente em relação a MSPA e MSPR. Para as variáveis fisiológicas, não houve resposta direta com as doses de N ou P, sendo o K o elemento que mais influenciou as variáveis, principalmente quando o calcário foi aplicado, resultando em maiores médias para fotossíntese, transpiração e condutância estomática. Com o objetivo de atender às demandas morfológicas e fisiológicas, a recomendação para o cultivo de Eucalyptus benthamii nas condições deste estudo é a dose 150-200-150, sem aplicação de calagem.(AU)

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The Drosophila genus is one of the main model organisms in evolutionary studies, including those investigating the role of transposable elements (TE) in genomic evolution both at the nucleotide and chromosome levels. D. incompta is a species with restricted ecology, using Cestrum (Solanaceae) flowers as unique sources for oviposition, feeding and development. In the present study, we deeply characterise the D. incompta mobilome and generate a curated dataset. A total of 277 elements were identified, corresponding to approximately 14% of the genome, and 164 of these elements are new, of which 32.62% are putatively autonomous and 8.9% are transcriptionally active in adult flies. The restricted ecology does not seem to influence the dynamics of TE in this fly, since the proportion and diversity of TEs in its genome are similar to that of other Drosophila species. This result is reinforced by the absence of a clear pattern when comparing the TE landscape between generalist and specialist flies. Using 32 available Drosophila genomes-24 ecologically generalist species and 8 specialist species-no difference was found between their TE landscape patterns. However, differences were found between species of the Sophophora and Drosophila subgenus, indicating there are lineage-specific factors shaping TE landscapes.

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RESUMO O artigo objetivou identificar as características das pesquisas na área de saúde sobre o tema cultura organizacional publicadas em revistas brasileiras. A busca foi efetuada na Biblioteca Virtual em Saúde a partir do termo 'cultura organizacional', no período de 2007 a 2016. Foram encontrados 30 artigos em revistas nacionais de Qualis A1, A2, B1 nas áreas de avaliação Capes (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior): enfermagem, saúde coletiva e psicologia. Os resultados evidenciaram o predomínio de artigos quantitativos e a aplicação de grande variedade de instrumentos para analisar a cultura organizacional na saúde, o que amplia as possibilidades de investigação e análise de diferentes aspectos do tema.

ABSTRACT The article aims to identify the characteristics of research studies in the healthcare field on organizational culture published in Brazilian journals. The search was carried out in the Virtual Health Library from the search term 'organizational culture', in the period between 2007 and 2016. Thirty (30) articles were found in national journals rated Qualis A1, A2, B1 in the following Capes (Coordination of Superior Level Staff Improvement) assessment areas: nursing, collective health and psychology. The results showed the prevalence of quantitative articles, and the application of a large variety of instruments to analyze organizational healthcare culture, which broadens the possibilities of investigation and analysis of different aspects of the theme.

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INTRODUCTION: A feedlot is an intensive farming system for finishing livestock. Bovine respiratory disease (BRD) is a cause of morbidity and mortality in beef cattle, especially in feedlots. METHODOLOGY: This study investigated the morbidity and mortality of BRD in a beef cattle feedlot in southeastern Brazil using: clinical diagnoses, therapy, morbidity, and mortality. Pulmonary fragments were collected from five steers, on feed from 3-32 days, with lesions of pneumonia for identification of BRD infectious agents PCR. RESULTS: 188,862 steers were on feed and morbidity was 7.05% (13,315/188,862), mortality 0.64% (1,214/188,862). The causes of morbidity were: BRD (6.13%), lameness (0.29%), trauma (0.21%), clostridiosis (0.13%) and polioencephalomalacia, PEM (0.12%). The causes of mortality were: BRD (0.21%), trauma (0.17%), and clostridiosis (0.13%). When all sick cattle were considered (n=13,315), BRD (86.9%) was the principal cause of morbidity, followed by lameness (4.13%), trauma (3.05%), and clostridiosis (1.82%). The cost of BRD-associated cattle mortality and morbidity was estimated at $14,334.00/10,000 and $16,315.40/10,000 respectively. It was projected that the economic effects due to BRD-associated morbidity in Brazil were $6.31 million/annum, while losses due to mortality were $5.54 million, resulting in an annual loss of $11.85 million. Coinfections in cattle with pneumonia due to Mannheimia haemolytica and Pasteurella multocida were identified in 4/5 steers tested. CONCLUSIONS: This is the first longitudinal study that investigated the incidence of BRD in feedlot cattle from Brazil, and the results herein described indicate that BRD contributed significantly to the development of mortality and morbidity of cattle on feed.

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ABSTRACT: Bovine respiratory diseases (BRD) affect production rates negatively because it compromise health and well-being of the affected animal. The hypothesis of this study was that the use of metaphylactic protocols based on the risk to develop BRD would reduce morbidity and pulmonary lesions. For this purpose, the aims of this study were to evaluate the effect of two metaphylactic protocols on the morbidity of feedlot cattle with a known sanitary history, occurrence of pulmonary lesions at slaughter, and the possible participation of Mannheimia haemolytica, Histophilus somni, Bovine alphaherpesvirus 1 (BoHV-1) and bovine respiratory syncytial virus (BRSV) in the development of BRD. An experimental study was designed in which 3,094 adult, male, cattle, were grouped according to the risk to develop BRD: a) group without metaphylaxis (n=2,104), low-risk animals; b) metaphylaxis group with oxytetracycline (n=789), moderate-risk animals; c) metaphylaxis group with tildipirosin (n=201), high-risk animals. All cattle were immunized against pathogens associated with BRD (BoHV-1, BVDV, BRSV, PI3). The morbidity for BRD was 8.2% (253/3,094); cattle within the moderate-risk group for BRD had the lowest frequency (6.1%), followed by high-risk animals with tildipirosin metaphylaxis (6.5%) and low-risk without metaphylaxis (9.1%) (P=0.019). At the abattoir, 1.2% of lungs with lesions were found. There was a difference (P=0.036) in the frequency of pulmonary lesions between healthy animals (1.1%) and those diagnosed with BRD (2.8%). Two agents associated with BRD were identified by PCR assays in the lungs (n=37) of cattle: M. haemolytica (16.2%) and H. somni (5.4%). In addition, concomitant infections involving these pathogens were identified in the lungs of two steers.(AU)

RESUMO: As doenças respiratórias dos bovinos (DRB) afetam negativamente as taxas de produção por comprometer a saúde e o bem-estar animal. A hipótese deste estudo foi que o uso de protocolos metafiláticos com base no risco de desenvolvimento de DRB reduziria a morbidade e as lesões pulmonares ao abate. Para tanto, objetivou-se avaliar o efeito de dois protocolos metafiláticos sobre a morbidade de bovinos confinados com histórico sanitário conhecido, ocorrência de lesões pulmonares no abate e possível participação de Mannheimia haemolytica, Histophilus somni, Alphaherpesvírus bovino 1 (BoHV-1) e Vírus respiratório sincicial bovino (BRSV) na DRB. Foram avaliados 3.094 bovinos adultos, machos, agrupados de acordo com o risco de desenvolvimento de DRB: a) grupo sem metafilaxia (n=2.104), animais de baixo risco; b) grupo metafilaxia com oxitetraciclina (n=789), animais de risco moderado; c) grupo metafilaxia com tildipirosina (n=201), animais de alto risco. Todos os animais foram previamente vacinados contra os principais agentes virais causadores das DRB (BoHV-1, BVDV, BRSV e PI3). A morbidade para DRB foi de 8,2% com menor frequência em animais com risco moderado e metafilaxia com oxitetraciclina (6,1%), seguido por animais com alto risco com metafilaxia com tildipirosina (6,5%) e animais com baixo risco sem metafilaxia (9,1%) (P=0,019). No frigorífico, foram encontrados 1,2% 1,2% de animais com lesões pulmonares. Houve diferença (P=0,036) na frequência de lesões pulmonares entre animais saudáveis (1,1%) e aqueles diagnosticados com DRB (2,8%). Foram identificados dois agentes associados à DRB pela técnica de PCR nos pulmões (n=37) dos bovinos: M. haemolytica (16,2%) e H. somni (5,4%). Adicionalmente, infecções concomitantes envolvendo estes potenciais patógenos foram identificadas nos pulmões de dois animais.(AU)

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ABSTRACT: Bovine respiratory diseases (BRD) affect production rates negatively because it compromise health and well-being of the affected animal. The hypothesis of this study was that the use of metaphylactic protocols based on the risk to develop BRD would reduce morbidity and pulmonary lesions. For this purpose, the aims of this study were to evaluate the effect of two metaphylactic protocols on the morbidity of feedlot cattle with a known sanitary history, occurrence of pulmonary lesions at slaughter, and the possible participation of Mannheimia haemolytica, Histophilus somni, Bovine alphaherpesvirus 1 (BoHV-1) and bovine respiratory syncytial virus (BRSV) in the development of BRD. An experimental study was designed in which 3,094 adult, male, cattle, were grouped according to the risk to develop BRD: a) group without metaphylaxis (n=2,104), low-risk animals; b) metaphylaxis group with oxytetracycline (n=789), moderate-risk animals; c) metaphylaxis group with tildipirosin (n=201), high-risk animals. All cattle were immunized against pathogens associated with BRD (BoHV-1, BVDV, BRSV, PI3). The morbidity for BRD was 8.2% (253/3,094); cattle within the moderate-risk group for BRD had the lowest frequency (6.1%), followed by high-risk animals with tildipirosin metaphylaxis (6.5%) and low-risk without metaphylaxis (9.1%) (P=0.019). At the abattoir, 1.2% of lungs with lesions were found. There was a difference (P=0.036) in the frequency of pulmonary lesions between healthy animals (1.1%) and those diagnosed with BRD (2.8%). Two agents associated with BRD were identified by PCR assays in the lungs (n=37) of cattle: M. haemolytica (16.2%) and H. somni (5.4%). In addition, concomitant infections involving these pathogens were identified in the lungs of two steers.

RESUMO: As doenças respiratórias dos bovinos (DRB) afetam negativamente as taxas de produção por comprometer a saúde e o bem-estar animal. A hipótese deste estudo foi que o uso de protocolos metafiláticos com base no risco de desenvolvimento de DRB reduziria a morbidade e as lesões pulmonares ao abate. Para tanto, objetivou-se avaliar o efeito de dois protocolos metafiláticos sobre a morbidade de bovinos confinados com histórico sanitário conhecido, ocorrência de lesões pulmonares no abate e possível participação de Mannheimia haemolytica, Histophilus somni, Alphaherpesvírus bovino 1 (BoHV-1) e Vírus respiratório sincicial bovino (BRSV) na DRB. Foram avaliados 3.094 bovinos adultos, machos, agrupados de acordo com o risco de desenvolvimento de DRB: a) grupo sem metafilaxia (n=2.104), animais de baixo risco; b) grupo metafilaxia com oxitetraciclina (n=789), animais de risco moderado; c) grupo metafilaxia com tildipirosina (n=201), animais de alto risco. Todos os animais foram previamente vacinados contra os principais agentes virais causadores das DRB (BoHV-1, BVDV, BRSV e PI3). A morbidade para DRB foi de 8,2% com menor frequência em animais com risco moderado e metafilaxia com oxitetraciclina (6,1%), seguido por animais com alto risco com metafilaxia com tildipirosina (6,5%) e animais com baixo risco sem metafilaxia (9,1%) (P=0,019). No frigorífico, foram encontrados 1,2% 1,2% de animais com lesões pulmonares. Houve diferença (P=0,036) na frequência de lesões pulmonares entre animais saudáveis (1,1%) e aqueles diagnosticados com DRB (2,8%). Foram identificados dois agentes associados à DRB pela técnica de PCR nos pulmões (n=37) dos bovinos: M. haemolytica (16,2%) e H. somni (5,4%). Adicionalmente, infecções concomitantes envolvendo estes potenciais patógenos foram identificadas nos pulmões de dois animais.

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