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Sporothrix brasiliensis is the main agent of zoonotic sporotrichosis transmitted by domestic cats in South America. In humans, sporotrichosis commonly presents with cutaneous or lymphocutaneous lesions, and in cats, with multiple ulcerated skin lesions associated with enlarged lymph nodes and respiratory signs. Fungal virulence factors may affect the clinical presentation of the mycoses. Sporothrix spp. present some virulence factors. This study aims to compare 24 S. brasiliensis strains from 12 familiar outbreaks of cat-to-human transmitted sporotrichosis. Fungal growth in different substrates, thermotolerance, resistance to oxidative stress, and production of enzymes were evaluated. An invertebrate model of experimental infection was used to compare the virulence of the strains. The strains grew well on glucose and N-acetyl-D-glucosamine but poorly on lactate. Their thermotolerance was moderate to high. All strains were susceptible to hydrogen peroxide, and the majority produced hemolysins but not phospholipase and esterase. There was no significant difference in the putative virulence-associated factors studied among the different hosts. Moreover, strains isolated from a human and a cat from four familiar outbreaks presented a very similar profile of expression of these factors, reinforcing the zoonotic transmission of S. brasiliensis in Brazil and demonstrating the plasticity of this species in the production of virulence factors. [ABSTRACT FROM AUTHOR]

Global warming is exposing many organisms to severe thermal conditions and is having impacts at multiple levels of biological organisation, from individuals to species and beyond. Biotic and abiotic factors can influence organismal thermal tolerance, shaping responses to climate change. In eusocial ants, thermal tolerance can be measured at the colony level (among workers within colonies), the population level (among colonies within species), and the community level (among species). We analysed critical thermal maxima (CT max ) across these three levels for ants in a semiarid region of northeastern Brazil. We examined the individual and combined effects of phylogeny, body size (BS), and nesting microhabitat on community-level CT max and the individual effects of BS on population- and colony-level CT max . We sampled 1864 workers from 99 ant colonies across 47 species, for which we characterised CT max , nesting microhabitat, BS, and phylogenetic history. Among species, CT max ranged from 39.3 to 49.7°C, and community-level differences were best explained by phylogeny and BS. For more than half of the species, CT max differed significantly among colonies in a way that was not explained by BS. Notably, there was almost as much variability in CT max within colonies as within the entire community. Monomorphic and polymorphic species exhibited similar levels of CT max variability within colonies, a pattern not always explained by BS. This vital intra- and inter-colony variability in thermal tolerance is likely allows tropical ant species to better cope with climate change. Our results underscore why ecological research must examine multiple levels of biological organisation.

• Evaluate of vascular hemodynamics of the scrotum using Doppler ultrasonography in Braford bulls. • The mean skin thickness of animals with long/moderate and moderate/oval formats was similar. • The mean velocity, systolic peak and end velocity was equal in animals with a long/moderate scrotal format compared to animals with moderate/oval. • No significant differences were observed between the RI or PI values and the two groups of scrotal formats evaluated. The objectives of this study were to determinate the scrotal shape and to evaluate the skin thickness and the vascular hemodynamics using Doppler ultrasonography in Braford bulls. This experiment was performed at a farm located in the municipality of Santana do Livramento, Rio Grande do Sul state, Brazil. A total of 106 Braford bulls, 16 months old, were housed under extensive breeding conditions. The mean temperature on the day measurements were taken was 22.6 ± 2.9 °C, and the relative humidity was 78 ± 9%. These values were used to calculate the Temperature and Humidity Index (THI), which was 70.69 ± 3.32. Doppler ultrasonography was used to evaluate vascular hemodynamics and obtain mean velocity (MV) (cm/s), end diastolic velocity (EV) (cm/s), systolic peak (SP) (cm/s), and indexes of pulsatility (PI) and resistivity (RI). Skin thickness was measured by ultrasonography, and the scrotal formats were classified as long-moderate (L/M) and moderate-oval (M/O). Tukey's test was used to evaluate the means, and a Pearson's linear correlation was established. The minimum level of significance was set at 5%. The MV had no significant difference in animals with M/O (14.98 ± 5.06) scrotal format compared to animals with L/M (13.66 ± 4.64). No difference was found (P > 0.05) in mean skin thickness of animals with L/M formats (3.70 ± 0.67 mm) and animals with M/O (3.63 ± 0.54 mm). The systolic peak did not differ in animals with L/M (18.01 ± 5.96) and M/O (20.21 ± 6.53) testes. The difference was not significant between EV in L/M testes (9.54 ± 4.01) and animals with M/O (10.45 ± 4.33). The RI and PI values, considering the two groups of scrotal shapes, did not show any significant difference. The correlations found were as follows: PI and RI = 0.95, EV and RI = -0.62, and EV and PI = -0.61. The relationships between blood flow and RI, as well as blood flow and skin thickness, were negative, indicating an inverse proportionality between the characteristics. Doppler ultrasonography was effective in evaluating vascular hemodynamics in Braford bulls raised in extensive production systems. The results found here suggest that the testicular format (L/M; M/O) is not related to skin thickness or testicular hemodynamics under these conditions. [ABSTRACT FROM AUTHOR]

Heat tolerance, especially under climate change scenarios, plays an increasingly import factor in pig and chicken production. We therefore evaluated bibliographic mapping of citation, co-occurrence of keywords, co-citation and bibliographic coupling for heat tolerance, and these species. Data was obtained from Scopus (Elsevier) and analysed in Vosviewer. We found a total of 2023 documents from 102 countries, of which 10 countries account for 50% of the publications (USA, China, Brazil, Iran, India, UK, Turkey, Germany, Egypt, and Australia). While heat tolerance is important worldwide, Global South countries, especially China, have become more prominent in publishing on this topic in recent years. Researchers from South America appear relatively isolated using the metrics of this study, with no clear explanation why. We speculate funding for research and publication may be a governing factor. The literature reviewed suggests an emphasis on mitigation strategies that include nutrition and genetics. An emphasis in poultry, especially Gallus gallus was observed and suggests more attention is needed on other species (for example, ducks and turkey). Biases in the analysis could arise due to lack of citations from recent papers, those not indexed in Scopus or in other languages. The paper advances understanding tendencies in this field of research and may point to future actions for policy makers addressing animal production and climate change research., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Cordyceps fumosorosea is an entomopathogenic fungus with a global distribution and is used for the biological control of agricultural pests. High conidial productivity and tolerance to abiotic stresses such as elevated temperature and ultraviolet radiation (UV-B) are desired characteristics in candidate isolates for commercial products. Our goal in this study was to characterize promising isolates of C. fumosorosea from five Brazilian biomes regarding conidial production, tolerance to UV-B, and elevated temperature (45°). Seventy-two isolates out of 172 were chosen visually, based on growth and sporulation in culture medium, and grown on parboiled rice. Next, fourteen isolates were selected, based on productivity on rice and origin of isolation, for production in polypropylene bags and submitted to UV-B for 2, 4, 6, and 8 h or to 45 °C for 30, 60, and 90 min. High variations in conidial production were observed among isolates, and a positive correlation was observed between UV-B and heat tolerance. The isolates ESALQ4556 and ESALQ4778 showed the highest yields of conidial production in polypropylene bags (3.51 × 10 9 conidia/g dry rice), while ESALQ1296, an isolate recovered from insects, was the most tolerant to UV-B and 45 °C. Exposure to radiation for more than 4 h and placed directly at 45 °C for more than 30 min significantly reduced conidial germination for all C. fumosorosea isolates. These results contribute to a better understanding of the tolerance to abiotic factors of Brazilian isolates of C. fumosorosea., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Aims: Characterize Escherichia coli and E. coli -producing (STEC) isolates from Brazilian beef to determine heat resistance and the presence of the transmissible locus of stress tolerance (tLST)., Methods and Results: Twenty-two STEC previously isolated from beef and characterized as STEC by PCR were subjected to different heat survival challenges (60°C and 71°C). Furthermore, the three tLST-positive isolates and one tLST-negative isolate by PCR were selected for WGS analysis. Phenotypic results indicated that 3/22 (13.64%) were heat resistant, 12/22 (54.54%) were moderately resistant, and 7/22 (31.82%) were sensitive to heat treatments. WGS analyses showed that three isolates with heat resistance showed tLST with up to 80% and 42% of similarity by BLAST analysis, with the major tLST genes being responsible for the homeostasis module. However, WGS showed the absence of stx genes associated with tLST-positive isolates, albeit with virulence and resistance genes found in extraintestinal pathogenic E. coli (ExPEC)., Conclusion: Our findings demonstrate the presence of heat-resistant E. coli as well as confirm some tLST genes in E. coli isolated from Brazilian beef., (© The Author(s) 2022. Published by Oxford University Press on behalf of Applied Microbiology International.)

Premise: The distribution and even the survival of plant species are influenced by temperature. In an old climatically buffered infertile landscape (OCBIL) in Brazil, we previously characterized different strategies for foliar water uptake (FWU). It is possible that photosystem II tolerance to heat and excessive light intensity varies among species with different FWU capacities., Methods: The relationship between FWU, photoinhibition, and thermotolerance was investigated in seven species from this ecosystem., Results: The species with slow water absorption and high water absorption are those that presented less photoinhibition. Contrastingly, the species that have fast and low water absorption presented greater thermotolerance when their leaves are totally hydrated. However, when there is greater leaf dehydration, the most thermotolerant species were those with slow but high water absorption., Conclusions: Foliar water uptake is an important trait for plants to tolerate excessive light intensity and higher temperatures. Plants in this OCBIL may be differentially affected by future global warming, and the best strategy to deal with this expected climate change is with slow and high absorption of water., (© 2021 Botanical Society of America.)

Using data related to thermal optimal and pejus of the embryos of Octopus americanus from Brazil and O. insularis and O. maya from Mexico, this study aimed to project the potential distribution areas in the Gulf of Mexico and predict distribution shifts under different Representative Concentration Pathway scenarios (RCP 6 and 8.5) for the years 2050 and 2100. The different thermal tolerances elicited different responses to current and future scenarios. In this sense, O. insularis and O. maya thermal niches stretch from the Caribbean to Florida. Nevertheless, O. insularis may inhabit warmer areas than O. maya. Surprisingly, no area was considered thermally habitable for O. americanus, which could have been associated with the use of data of populations thermally adapted to temperate conditions south of Brazil. According to models, a warming scenario would cause a restriction of the available thermal niche of O. maya, while O. insularis could expand under RCP 6 scenarios. This restriction was more substantial in the RCP 8.5 scenario. Nevertheless, under the RCP 8.5 scenario, the temperature in 2100 may negatively affect even O. insularis, the species most thermal tolerant. If our results are accurate, the fishing yield of O. insularis will increase in the future, replacing the heavily exploited O. maya in the coasts of the southern Gulf of Mexico. Regarding O. americanus, no inference might be made until thermal tolerances of locally adapted populations can be studied., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The aim of this study was to select and identify thermophilic bacteria from Caatinga biome (Brazil) able to produce thermoactive keratinases and characterize the keratinase produced by the selected isolate. After enrichment in keratin culture media, an Anoxybacillus caldiproteolyticus PC2 was isolated. This thermotolerant isolate presents a remarkable feature producing a thermostable keratinase at 60°C. The partially purified keratinase, identified as a thermolysin-like peptidase, was active at a pH range of 5.0-10.0 with maximal activity at a temperature range of 50-80°C. The optimal activity was observed at pH 7.0 and 50-60°C. These characteristics are potentially useful for biotechnological purposes such as processing and bioconversion of keratin., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Chicken is a leading source of thermotolerant Campylobacter, which triggers human foodborne enteritis. This study evaluated thermotolerant Campylobacter contamination of retail chicken in southern Brazil, using qualitative and quantitative analyses. Selective enrichment in Bolton broth for 24 and 48 h after plating onto modified charcoal-cefoperazone-deoxycholate (mCCD) agar and Preston agar was assessed. The combined results of the detection and enumeration methods revealed a frequency of 70% occurrence of thermotolerant Campylobacter in chicken samples. Campylobacter was enumerated in 60% of the samples, whereas 46% of the samples were positive in the qualitative analysis. Quantitative analysis showed average counts of 3.10 ± 0.15 log 10  CFU/sample. Higher numbers of Campylobacter-positive samples were found using 24-h enrichment before plating onto Preston agar (46%) than onto mCCD agar (2%). The majority of isolated strains were identified as Campylobacter jejuni, and Campylobacter coli was also found but to a lesser extent. Subtyping revealed a clear distinction between strains isolated from different chicken sources. The enriched samples plated onto mCCD agar showed extensive spreading of nonproducing extended-spectrum β-lactamases Proteus mirabilis that hampered the identification of Campylobacter colonies. P. mirabilis strains showed resistance to cefoperazone, trimethoprim, and polymyxin B present in broth and plate media used and were inhibited by rifampicin present in Preston agar. The results underline the effect of the spread of contaminant strains on Campylobacter cultures, which might be prevented using a recently revised International Organization for Standardization method for qualitative analysis of chicken., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Tambaqui (Colossoma macropomum Cuvier, 1818) is an endemic fish of the Amazon and Orinoco basins, and it is the most economically important native species in Brazil being raised in five climatically distinct regions. In the face of current global warming, environmental variations in farm ponds represent additional challenges that may drive new adaptive regional genetic variations among broodstocks of tambaqui. In an experimental context based on the high-emission scenario of the 5th Intergovernmental Panel on Climate Change (IPCC) report, we used two farmed tambaqui populations to test this hypothesis. RNA-seq transcriptome analysis was performed in the liver of juvenile tambaqui from northern (Balbina Experimental Station, Balbina, AM) and southeastern (Brumado Fish Farming, Mogi Mirim, SP) Brazilian regions kept for 30 days in artificial environmental rooms mimicking the current and extreme climate scenarios. Three Illumina MiSeq runs produced close to 120 million 500 bp paired-end reads; 191,139 contigs were assembled with N50 = 1595. 355 genes were differentially expressed for both populations in response to the extreme scenario. After enrichment analysis, each population presented a core set of genes to cope with climate change. Northern fish induced genes related to the cellular response to stress, activation of MAPK activity, response to unfolded protein, protein metabolism and cellular response to DNA damage stimuli. Genes biologically involved in regulating cell proliferation, protein stabilisation and protein ubiquitination for degradation through the ubiquitin-proteasome system were downregulated. Genes associated with biological processes, including the cellular response to stress, MAPK cascade activation, homeostatic processes and positive regulation of immune responses were upregulated in southeastern fish. The downregulated genes were related to cytoskeleton organisation, energy metabolism, and the regulation of transcription and biological rhythms. Our findings reveal the signatures of promising candidate genes involved in the regional plasticity of each population of tambaqui in dealing with upcoming climate changes., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Aims: The aim of this study was to evaluate the microbiological quality of commercially prepared ready-to-eat (RTE) sushi by enumerating aerobic mesophilic bacteria (AMB) and thermotolerant coliforms (TC) and detecting Escherichia coli and Salmonella ssp. An isolate was identified as E. coli O157:H7 which was evaluated for its virulence and antimicrobial resistance profiling as well as its ability to form biofilms on stainless steel., Methods and Results: There were four sampling events in seven establishments, totalling 28 pools of sushi samples. Mean AMB counts ranged between 5·2 and 7·7 log CFU per gram. The enumeration of TC varied between 2·1 and 2·7 log MPN per gram. Salmonella ssp. were not detected, and one sample was positive for E. coli and was identified as E. coli O157:H7. To the best of our knowledge, this is the first report of E. coli O157:H7 in sushi samples in the world literature. This isolate presented virulence genes stx1, stx2, eae and hlyA. It was also susceptible to 14 antimicrobials tested and had the ability to form biofilms on stainless steel., Conclusions: There is a need to improve the good hygiene practices adopted in establishments selling sushi in the city of Pelotas, Brazil. In addition, the isolated E. coli O157:H7 carries a range of important virulence genes being a potential risk to consumer health, as sushi is a RTE food. This isolate also presents biofilm formation ability, therefore, may trigger a constant source of contamination in the production line of this food., Significance and Impact of the Study: The increase in the consumption of sushi worldwide attracts attention regarding the microbiological point of view, since it is a ready-to-eat food. To our knowledge, this was the first time that E. coli O157:H7 was identified in sushi samples., (© 2019 The Society for Applied Microbiology.)

A study using sentinel broiler chickens was performed to address Campylobacter persistence in litter that was reused for successive flocks. Cloacal swabs, litter, drag swabs, darkling beetles, feed, and drinking water were weekly sampled and analyzed by standard microbiological procedures. Thermotolerant Campylobacter isolated strains were confirmed by polymerase chain reaction and subtyped by pulsed-field gel electrophoresis analysis. Campylobacter was not detected in samples collected immediately after downtime between broiler flocks. However, Campylobacter -positive samples were first detected at 21 d. After Campylobacter was initially isolated from the cloacal swabs, reused litter, drag swabs, or darkling beetles, these samples remained Campylobacter positive in the following weeks until the end of the rearing period. Campylobacter -positive cloacal swabs obtained from sentinel broilers ranged from 97.3% to 100% at 42 d. All isolated strains were identified as Campylobacter jejuni . Among the subtypes identified, an indistinguishable C . jejuni strain was predominant in sentinel broilers and was also detected in the other environmental samples analyzed, suggesting a common and persistent contamination source within the flocks. Sentinel broilers may have contributed to amplify the Campylobacter level, maintaining flock and broiler house contamination until the end of the production cycle.

Heat stress is one of the most important factors that affect the performance of some Bos taurus breeds and crosses in tropical regions. The Brahman breed was developed in hot regions of the world and often has genes that confer resistance to heat stress compared to other breeds of beef cattle. The goal of this work was to evaluate the adaptive responses of Brahman bulls, based on physiological, hormonal and hair characteristics according to season. The physiological, hormonal and hair characteristics were rectal temperature (R T ), respiratory rate (R R ), sweating rate (S R ), triiodothyronine (T 3 ), thyroxine (T 4 ), cortisol concentrations (C O ), coat thickness (C T ), hair length (H L ), hair diameter (H D ) and hair density (N D ). These were recorded in Brahman bulls from a Cerrado biome during four seasons: spring (21 September to 20 December), summer (21 December to 17 March), autumn (18 March to 20 June) and winter (21 June to 20 September). Data was analyzed using a general linear model that included season as a fixed effect; in addition, multivariate tests and logistic regression were also used to characterize the animals within each season. The meteorological variables defined the four seasons, besides identifying climatic differences between them. Significant differences (P > 0.05) were found for most of the physiological, hormonal and hair characteristics according to season. The Brahman bulls presented particular adaptive characteristics in each season. Individually, most of the Brahman bulls presented the same adaptive reaction in each season; particular similarity occurred for the summer and autumn. This pattern is a reflection of the inter-relationships between physiological responses and hair characteristics., (Copyright © 2019. Published by Elsevier Ltd.)

Knowledge of thermoregulatory responses in taurine cattle contribute to identification of animals most adapted to heat and productive when raised under Brazilian climate. The objectives were to verify the morphological and physiological responses related to adaptation to heat of taurine breeds raised under in Brazilian meteorological conditions in different seasons of the year and day periods, and to detect differences within and between breeds to know breed is most adapted. Measurements were made of 74 young bulls (n = 31 Angus; n = 43 Simmental) for the morphological traits: hair length (HL), number of hairs (NH), and coat thickness (CT); and for the physiological traits: respiratory rate (RR) and hair coat surface temperature (ST). The temperature-humidity index (THI) was calculated. The data were subjected to analyses of variance, cluster analysis, and principal component analysis (PCA). The THI (<74) indicates thermal comfort. In the winter, the HL and CT higher than in the spring season (P < 0.0001) in both breeds. Angus exhibited higher HL and CT (P < 0.0001). Within each breed, the animals differed from one another for HL (P < 0.0005). In the spring, CT was similar between the breeds, differing only in the winter season. Angus had higher values (P < 0.0005) of RR and lower values (P < 0.0001) of ST. Both breeds had higher (P < 0.0001) RR and ST in the afternoon. PCA showed that NH and HL better explained variation in adaptation. In general, the breeds have similar morphological responses in the hottest months, but have different physiological responses; Simmental proves to be more physiologically resistant. The afternoon was more stressful than the morning, even though the animals were in a thermal comfort zone. Measuring traits related to hair coat is sufficient for effective evaluation of adaptation, and the season affects the morphological and physiological traits of taurine cattle raised., (Copyright © 2019. Published by Elsevier Ltd.)

Functional screening of metagenomic libraries is an important tool for the discovery of new molecules. The metabolic diversity of microorganisms enables survival in harsh environments and is related to the production of enzymes. In this study, we identified a protease-producing clone from a metagenomic library derived from mangrove sediment. The protease was purified by ammonium sulphate precipitation and gel filtration chromatography, with a yield of 77.27% and a specific activity of 8.57 U μg -1 . It had a molecular weight of approximately 70 kDa. MS/MS in ESI-Q-TOF revealed nine peptides similar to a peptidase of Bacillus safensis. The aligned partial sequence showed 47.48% identity and 82.74% similarity to the conserved domains of a glutamyl aminopeptidase from the human gut metagenome and 32.12% total coverage. The protease had an optimal pH of 8.5 and optimal activity at 60°C. At pH 9-12, its activity was greater than 80%. It had moderate thermotolerance and thermostability at temperatures of 40 and 50 °C. The K M and V max values were estimated to be 0.92 mg ml -1 , and 13.15 mmol min -1 for azocasein. Substrate specificity analysis showed that PR4A3 was active on gelatin, blood, egg yolk, and milk. These results support the potential use of PR4A3 in biotechnological applications., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The objective of this study was to characterize the C. jejuni IAL2383 strain isolated from humans in Brazil. Transcripts for the racR, dnaJ and ciaB genes were found and flaA, plda and cadF genes were present in the genome and bacteria was sensitive to most of the important antimicrobials used to treat humans. C. jejuni IAL2383 is a good experimental model to analyze the interactions with cells.