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The One Health concept recognizes that human health is clearly linked to the health of animals and the environment. Infections caused by bacteria resistant to carbapenem antibiotics have become a major challenge in hospitals due to limited therapeutic options and consequent increase in mortality. In this study, we investigated the presence of carbapenem-resistant Enterobacteriaceae in 84 effluent samples (42 from hospital and 42 from non-hospital) from Campo Grande, midwest Brazil. First, sewage samples were inoculated in a selective culture medium. Bacteria with reduced susceptibility to meropenem and ertapenem were then identified and their antimicrobial susceptibility was determined using the Vitek-2 system. The blaKPC genes were detected using PCR and further confirmed by sequencing. Carbapenem-resistant Enterobacteriaceae (CRE) were identified in both hospital (n=32) and non-hospital effluent (n=16), with the most common being Klebsiella pneumoniae and of the Enterobacter cloacae complex species. This is the first study to indicate the presence of the blaKPC-2 gene in carbapenem-resistant Enterobacteriaceae, classified as a critical priority by the WHO, in hospital sewage in this region. The dissemination of carbapenem antibiotic-resistant genes may be associated with clinical pathogens. Under favorable conditions and microbial loads, resistant bacteria and antimicrobial-resistance genes found in hospital sewage can disseminate into the environment, causing health problems. Therefore, sewage treatment regulations should be implemented to minimize the transfer of antimicrobial resistance from hospitals.

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The aim of this study was to evaluate the antibacterial and antioxidant activities of essential oil (EO) from fresh leaves of Psidium rufum. The EO was extracted by hydrodistillation and identified by gas chromatography coupled to mass spectrometry. The antibacterial activity was evaluated by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Antioxidant activity was determined by ß-carotene/linoleic acid co-oxidation system, 2,2-diphenyl-1-picrylhydrazyl radical scavenging and iron reduction methods. Hydrocarbon sesquiterpenes were the predominant class, indicating 1,8 cineole, α-longipinene as major. The EO was tested against the bacteria Staphylococcus aureus and Pseudomonas aeruginosa (MIC = 2,500 µg/mL and MBC = 20,000 µg/mL); Enterococcus faecalis (MIC = 2,500µg/mL and MBC > 20,000µg/mL) and Escherichia coli (MIC > 20,000µg/mL and MBC > 20,000µg/mL). The EO showed antioxidant potential due to ß-carotene/linoleic acid co-oxidation system, with 76.63% of oxidation inhibition (1.0mg/mL) and due to the iron reduction power (5,38 µmol Fe 2+ /mg sample). The results are promising in recommending this species for the development of food, cosmetic and pharmaceutical products.

O objetivo deste estudo foi avaliar as atividades antibacteriana e antioxidante do óleo essencial (OE) das folhas frescas de Psidium rufum. O OE foi extraído por hidrodestilação e identificado por cromatografia gasosa acoplada à espectrometria de massas. Foi avaliada a atividade antibacteriana, determinando-se a concentração inibitória mínima (CIM) e a concentração bactericida mínima (CBM). A atividade antioxidante foi determinada pelo sistema de co-oxidação ß-caroteno/ácido linoleico, pelos métodos de sequestro do radical 2,2-difenil-1-picrilhidrazil e de redução do ferro. Sesquiterpenos hidrocarbonetos foram a classe predominante, indicando 1,8 cineol, α-longipineno como majoritário. O OE foi testado contra as bactérias Staphylococcus aureus e Pseudomonas aeruginosa (CIM = 2,500µg/mL e CBM = 20.000µg/mL); Enterococcus faecalis (CIM=2,500µg/mL e CBM > 20.000µg/mL) e Escherichia coli (CIM > 20.000µg/mL e CBM > 20.000µg/mL). O OE apresentou potencial antioxidante pelo sistema co-oxidação ß-caroteno/ácido linoleico com 76,63% de inibição da oxidação (1,0mg/mL) e pelo poder de redução de ferro (5,38 µmol Fe2+/mg amostra). Os resultados são promissores em indicar essa espécie para o desenvolvimento de produtos alimentícios, cosméticos e farmacêuticos.

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Este trabalho objetivou o isolamento e a identificação das bactérias de diferentes microbiotas de lhamas. Para tanto, testes de disco difusão e diagnósticos moleculares para pesquisa de genes de resistência foram realizados. Foram isolados cinco Staphylococcus spp. coagulase positiva e 19 Staphylococcus spp. coagulase negativa, 19 Escherichia coli¸ duas Pantoea agglomerans, uma Koserella trabulsii, uma Enterobacter aerogenes e uma Klebsiella Pneumoniae. Entre os isolados de Staphylococcus spp., 79,17% foram resistentes ao sulfazotrim, 45,83% resistentes à penicilina e 20,83% à ampicilina. Foi confirmada a presença do gene mecA em apenas um isolado oxacilina resistente. No teste de disco difusão, 58,3% das enterobactérias foram resistentes à amoxicilina + ácido clavulânico e à cefotaxima, 50% à ceftazidima e ceftriaxona, e 33,3% à amoxicilina. Ainda entre os isolados Gram-negativos, não houve a expressão fenotípica de isolados ESBL. O presente trabalho expôs a presença de microrganismos resistentes a antibióticos em lhamas que não tiveram contato prévio com essas drogas, além da presença do gene mecA em um dos animais. O conhecimento da microbiota bacteriana de diferentes espécies animais tem se tornado cada vez mais importante. Tal relevância se deve à possibilidade de esses microrganismos serem compartilhados entre os animais, os humanos e até mesmo o meio ambiente.

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The tropical peatlands of southern Brazil are essential for the maintenance of the Atlantic Rain Forest, one of the 25 hotspots of biodiversity in the world. Although diazotrophic micro-organisms are essential for the maintenance of this nitrogen limited ecosystem, so far studies have focused only on micro-organisms involved in the carbon cycle. In this work, peat samples were collected from three tropical peatland regions during dry and rainy seasons and their chemical and microbial characteristics were evaluated. Our results showed that the structure of the diazotrophic communities in the Brazilian tropical peatlands differs in the evaluated seasons. The abundance of the genus Bradyrhizobium showed to be affected by rainfall and peat pH. Despite the shifts of the nitrogen-fixing population in the tropical peatland caused by seasonality it showed to be constantly dominated by α-Proteobacteria followed by Cyanobacteria. In addition, more than 50% of nifH gene sequences have not been classified, indicating the necessity for more studies in tropical peatland, since the reduction of N supply in the peatlands stimulates the recalcitrant organic matter decomposition performed by peatland micro-organisms, influencing the C stock.

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The use of Azospirillum brasilense as a crop inoculant has increased in recent years. Thus, the compatibility of the inoculation technology with seed treatments using pesticides needs to be evaluated. In this study, we evaluated the effect of an insecticide and fungicide formulation on A. brasilense strain FP2 population by culturing and culture-independent approaches. In addition, we evaluated the impact of these pesticides on the ability of A. brasilense to promote plant growth by monitoring biometric traits (root and shoot dry mass and length) of wheat grown in Greenhouse conditions. Seed pesticide dressings, mainly fungicide, led to a significant mortality of A. brasilense over time. The ability of A. brasilense to promote wheat growth also decreased due to pesticide treatments combined with sowing delay. Considering that pesticides confer fitness advantages to the wheat in field condition, our results suggest that sowing within the first 4 h after inoculation maintain the beneficial effects of A. brasilense on wheat growth promotion. Furthermore, we conclude that inoculation and treatment of seeds with pesticides may be compatible techniques when carried out immediately before sowing.

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The skin injury healing process involves the main phases of homoeostasis, inflammation, proliferation, and remodeling. The present study aimed to analyze the effects of low-level laser therapy (LLLT) on hematological dynamics, oxidative stress markers, and its relation with tissue healing following skin injury. Wistar rats were divided into control, sham, skin injury, and skin injury LLLT. The biochemical and morphological analyses were performed in the inflammatory (1 and 3 days) and regenerative phases (7, 14, and 21 days) following injury. The skin injury was performed in the dorsal region, between the intrascapular lines, using a surgical punch. LLLT (Al-Ga-In-P, λ=660 nm, energy density of 20 J/cm2, 30 mW power, and a time of 40 s) was applied at the area immediately after injury and on every following day according to the experimental subgroups. LLLT maintained hematocrit and hemoglobin levels until the 3rd day of treatment. Surprisingly, LLLT increased total leukocytes levels compared to control until the 3rd day. The effects of LLLT on mitochondrial activity were demonstrated by the significant increase in MTT levels in both inflammatory and regenerative phases (from the 1st to the 7th day), but only when associated with skin injury. The results indicated that LLLT modulated the inflammatory response intensity and accelerated skin tissue healing by a mechanism that involved oxidative damage reduction mostly at early stages of skin healing (inflammatory phase).

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This study aimed to identify, by means of thromboelastometry assessment, altered thrombotic risk in dogs with primary and secondary IMHA by E. canis infection after initiating the immunosuppressive therapy with mycophenolate mofetil. The animals' screening was based on complete blood count (CBC), biochemical and urine tests. Dogs with moderate to severe anemia (hematocrit ≤ 25%) which showed symptoms of immune-mediated hemolysis, such as spherocytosis, positive saline agglutination, bilirubinuria and/or hemoglobinuria, were included. Blood and urine samples were collected at two different moments. The first sample (M1) was collected at the time of diagnosis, when hematocrit was lower or equal to 25% before treatment with mycophenolate mofetil (Accord ®); the second sample (M2) was collected after treatment with mycophenolate mofetil, when hematocrit was greater or equal to 30%. Five out of the twelve animals selected died before the end of the study. No reduction in thrombotic risk was observed in the animals treated with mycophenolate mofetil. The animals that presented hypocoagulation at the time of diagnosis showed the worst prognosis, and their reticulocyte count displayed a better prognostic value than their erythrocytes count at the time of diagnosis.(AU)

O objetivo deste estudo foi esclarecer se há alteração do risco trombótico em cães com anemia hemolítica imunomediada primária e secundária a E.canis, avaliado por meio da tromboelastometria, após início de tratamento com micofenolato de mofetila. A seleção dos animais foi baseada na avaliação de hemograma, exame bioquímico e urinálise. Cães com anemia moderada a severa (hematócrito ≤ 25%), com sinais de hemólise imunomediada, como esferocitose, aglutinação em salina positivo, bilirrubinúria e/ ou hemoglobinúria, foram incluídos. As amostras de sangue e urina foram coletadas em dois momentos diferentes. A primeira amostra (M1) foi coletada no momento do diagnóstico, quando o hematócrito era igual ou inferior a 25%, sem fazer uso do micofenolato de mofetila (Accord®), e o segundo momento (M2), após tratamento com micofenolato de mofetila, quando o hematócrito era igual ou maior que 30%. Doze animais foram selecionados, cinco morreram antes do término do estudo. Não houve diminuição do risco trombótico entre os animais tratados com micofenolato de mofetila; os animais que apresentaram menor coagulabilidade apresentaram pior prognóstico, e a contagem de reticulócitos apresentou melhor valor prognóstico do que a contagem de hemácias no momento do diagnóstico.(AU)

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Fragments with vibrant colors and attractive textures in poultry house litter may be consumed considering that the confinement environment does not offer many opportunities for the development of the birds’s natural behavior. Control and quality programs aiming to reduce and to eliminate the consumption of materials from the construction of sheds have been implanted. However, it is necessary to develop studies for a better understanding of the bird’s ingestive behavior and the consequences for their health, welfare and productivity. The goal of this study was to evaluate the ingestive behavior of broilers exposed to metal, wood, glass and plastic fragments at different concentrations and sizes added to the poultry house litter and the integrity of the gastrointestinal tract of broilers. A total of 360 birds were distributed in a completely randomized design over a 2x3 factorial scheme (2 fragment sizes: 2 to 7 mm and 5 to 8 mm and 3 concentrations: 0.1, 0.5 and 1%), totaling 6 treatments and 5 replicates. The fragments used were glass, wood, metal and plastic, in respective concentrations and sizes, distributed in the poultry house litter. The supply of fragments or the accidental occurrence of similar fragments to which were analyzed in this study concerning the poultry house litter, with different sizes, colors and textures does not compromise the integrity of the mucosa of the gastrointestinal tract and the welfare of the birds.

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Fragments with vibrant colors and attractive textures in poultry house litter may be consumed considering that the confinement environment does not offer many opportunities for the development of the birdss natural behavior. Control and quality programs aiming to reduce and to eliminate the consumption of materials from the construction of sheds have been implanted. However, it is necessary to develop studies for a better understanding of the birds ingestive behavior and the consequences for their health, welfare and productivity. The goal of this study was to evaluate the ingestive behavior of broilers exposed to metal, wood, glass and plastic fragments at different concentrations and sizes added to the poultry house litter and the integrity of the gastrointestinal tract of broilers. A total of 360 birds were distributed in a completely randomized design over a 2x3 factorial scheme (2 fragment sizes: 2 to 7 mm and 5 to 8 mm and 3 concentrations: 0.1, 0.5 and 1%), totaling 6 treatments and 5 replicates. The fragments used were glass, wood, metal and plastic, in respective concentrations and sizes, distributed in the poultry house litter. The supply of fragments or the accidental occurrence of similar fragments to which were analyzed in this study concerning the poultry house litter, with different sizes, colors and textures does not compromise the integrity of the mucosa of the gastrointestinal tract and the welfare of the birds.(AU)

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The skin injury healing process involves the main phases of homoeostasis, inflammation, proliferation, and remodeling. The present study aimed to analyze the effects of low-level laser therapy (LLLT) on hematological dynamics, oxidative stress markers, and its relation with tissue healing following skin injury. Wistar rats were divided into control, sham, skin injury, and skin injury LLLT. The biochemical and morphological analyses were performed in the inflammatory (1 and 3 days) and regenerative phases (7, 14, and 21 days) following injury. The skin injury was performed in the dorsal region, between the intrascapular lines, using a surgical punch. LLLT (Al-Ga-In-P, λ=660 nm, energy density of 20 J/cm2, 30 mW power, and a time of 40 s) was applied at the area immediately after injury and on every following day according to the experimental subgroups. LLLT maintained hematocrit and hemoglobin levels until the 3rd day of treatment. Surprisingly, LLLT increased total leukocytes levels compared to control until the 3rd day. The effects of LLLT on mitochondrial activity were demonstrated by the significant increase in MTT levels in both inflammatory and regenerative phases (from the 1st to the 7th day), but only when associated with skin injury. The results indicated that LLLT modulated the inflammatory response intensity and accelerated skin tissue healing by a mechanism that involved oxidative damage reduction mostly at early stages of skin healing (inflammatory phase).

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A mastite bovina, uma das principais doenças do rebanho leiteiro, caracteriza-se por um processo inflamatório no úbere. A inviabilidade econômica, o impacto ambiental negativo e os resíduos antimicrobianos têm estimulado a pesquisa de outros tratamentos alternativos para a prevenção e o tratamento de doenças na bovinocultura leiteira. O betaglucano é um agente imunomodulador com potencial ação preventiva para doenças infecciosas, inclusive a mastite. Este estudo teve como objetivo avaliar a eficácia do uso do betaglucano, por meio de administração oral, em animais em lactação. Foram utilizadas 20 vacas lactantes, distribuídas em dois grupos, um controle e um tratamento, com 10 animais em cada grupo. O grupo tratamento recebeu 5g/dia, durante 60 dias, de 1,3-1,6 betaglucano isolado da parede celular de Saccharomyces cerevisiae diluído em ração após a ordenha, enquanto o grupo controle recebia somente a ração. Foram realizados os testes de California Mastitis Test (CMT), contagem de células somáticas (CCS), produção de leite e percentual de gordura e proteína no leite. Não houve diferença estatisticamente significativa entre os grupos quanto à CCS, ao CMT, à composição do leite ou produção. Não se observou, portanto, eficácia do uso do betaglucano purificado, administrado por via oral, no controle e na prevenção da mastite em vacas leiteiras, quando comparadas com o grupo controle. Atribuem-se esses resultados, principalmente, à degradação ruminal do produto testado. Sugerem-se, portanto, mais pesquisas utilizando o 1,3-1,6 betaglucano purificado de parede de S. cerevisiae por outras vias de administração, tais como intramamária e subcutânea.(AU)

Bovine mastitis, one of the main diseases of dairy herds, is characterized by an inflammatory process in the udder. The economic and environmental impacts, as well as the residues of antimicrobial drugs have stimulated the research of novel alternative treatments for the prevention and treatment of diseases in dairy production cows. The beta-glucan is an immunomodulator agent, with potential preventive action for infectious diseases, including mastitis. This study aimed to assess the effectiveness of orally administered beta-glucan in lactating cows. 20 lactating cows were used, distributed into two groups, one control and one treatment, with 10 cows in each group. The treatment group received 5g of 1.3-1.6 betaglucan daily for 60 days, isolated from the cell-wall of Saccharomyces cerevisiae diluted into a grain meal, whereas the animals in the control group received only the ration. The California Mastitis Test (CMT), Somatic Cells Counting (SCC), daily production and assessments of fat and protein content in milk were done. There was no statistically significant difference between the groups concerning subclinical mastitis detected by CMT, SCC, milk production and composition regarding protein and fat content. It was not observed, therefore, the effectiveness of the use of purified beta-glucan orally administered on the control or prevention of mastitis in dairy cows. The results are attributed to the ruminal degradation of the product tested. It is, therefore, suggested that more research should be conducted using the 1.3-1.6 beta-glucan purified from the cell wall of S. cerevisiae by other administration means and ruminal protection technologies for the isolated beta-glucan.(AU)

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O objetivo deste estudo foi realizar a caracterização genética de Staphylococcus spp. resistentes a meticilina isolados de suínos. Foram coletadas 30 amostras de swab nasal de suínos, abatidos em um frigorífico com Serviço de Inspeção Federal. Os isolados foram submetidos a análises macro e microscópicas que, em seguida, para detectar a resistência bacteriana, foram submetidos a ensaios fenotípicos da sensibilidade aos antimicrobianos. Posteriormente, as amostras resistentes a oxacilina, foram submetidas à reação em cadeia pela polimerase (PCR) para verificar a presença do gene mecA. Das 30 amostras analisadas, foram isolados 12 (40%) Staphylococcus spp. coagulase positiva, e 18 (60%) coagulase negativa, e, dentre os isolados, 26 (86,66%) foram resistentes a oxacilina sendo possível detectar o gene mecA em seis (23%) amostras. Este estudo evidencia a presença de genes de resistência em microrganismos comuns a microbiota de animais de produção que podem ser transmitidos ao homem. Além de chamar a atenção para a frequência e quantidade de antimicrobianos aos quais estes animais são expostos durante toda sua vida, podendo ser considerado um problema para a saúde única.(AU)

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A mastite bovina, uma das principais doenças do rebanho leiteiro, caracteriza-se por um processo inflamatório no úbere. A inviabilidade econômica, o impacto ambiental negativo e os resíduos antimicrobianos têm estimulado a pesquisa de outros tratamentos alternativos para a prevenção e o tratamento de doenças na bovinocultura leiteira. O betaglucano é um agente imunomodulador com potencial ação preventiva para doenças infecciosas, inclusive a mastite. Este estudo teve como objetivo avaliar a eficácia do uso do betaglucano, por meio de administração oral, em animais em lactação. Foram utilizadas 20 vacas lactantes, distribuídas em dois grupos, um controle e um tratamento, com 10 animais em cada grupo. O grupo tratamento recebeu 5g/dia, durante 60 dias, de 1,3-1,6 betaglucano isolado da parede celular de Saccharomyces cerevisiae diluído em ração após a ordenha, enquanto o grupo controle recebia somente a ração. Foram realizados os testes de California Mastitis Test (CMT), contagem de células somáticas (CCS), produção de leite e percentual de gordura e proteína no leite. Não houve diferença estatisticamente significativa entre os grupos quanto à CCS, ao CMT, à composição do leite ou produção. Não se observou, portanto, eficácia do uso do betaglucano purificado, administrado por via oral, no controle e na prevenção da mastite em vacas leiteiras, quando comparadas com o grupo controle. Atribuem-se esses resultados, principalmente, à degradação ruminal do produto testado. Sugerem-se, portanto, mais pesquisas utilizando o 1,3-1,6 betaglucano purificado de parede de S. cerevisiae por outras vias de administração, tais como intramamária e subcutânea.(AU)

Bovine mastitis, one of the main diseases of dairy herds, is characterized by an inflammatory process in the udder. The economic and environmental impacts, as well as the residues of antimicrobial drugs have stimulated the research of novel alternative treatments for the prevention and treatment of diseases in dairy production cows. The beta-glucan is an immunomodulator agent, with potential preventive action for infectious diseases, including mastitis. This study aimed to assess the effectiveness of orally administered beta-glucan in lactating cows. 20 lactating cows were used, distributed into two groups, one control and one treatment, with 10 cows in each group. The treatment group received 5g of 1.3-1.6 betaglucan daily for 60 days, isolated from the cell-wall of Saccharomyces cerevisiae diluted into a grain meal, whereas the animals in the control group received only the ration. The California Mastitis Test (CMT), Somatic Cells Counting (SCC), daily production and assessments of fat and protein content in milk were done. There was no statistically significant difference between the groups concerning subclinical mastitis detected by CMT, SCC, milk production and composition regarding protein and fat content. It was not observed, therefore, the effectiveness of the use of purified beta-glucan orally administered on the control or prevention of mastitis in dairy cows. The results are attributed to the ruminal degradation of the product tested. It is, therefore, suggested that more research should be conducted using the 1.3-1.6 beta-glucan purified from the cell wall of S. cerevisiae by other administration means and ruminal protection technologies for the isolated beta-glucan.(AU)

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O objetivo deste estudo foi realizar a caracterização genética de Staphylococcus spp. resistentes a meticilina isolados de suínos. Foram coletadas 30 amostras de swab nasal de suínos, abatidos em um frigorífico com Serviço de Inspeção Federal. Os isolados foram submetidos a análises macro e microscópicas que, em seguida, para detectar a resistência bacteriana, foram submetidos a ensaios fenotípicos da sensibilidade aos antimicrobianos. Posteriormente, as amostras resistentes a oxacilina, foram submetidas à reação em cadeia pela polimerase (PCR) para verificar a presença do gene mecA. Das 30 amostras analisadas, foram isolados 12 (40%) Staphylococcus spp. coagulase positiva, e 18 (60%) coagulase negativa, e, dentre os isolados, 26 (86,66%) foram resistentes a oxacilina sendo possível detectar o gene mecA em seis (23%) amostras. Este estudo evidencia a presença de genes de resistência em microrganismos comuns a microbiota de animais de produção que podem ser transmitidos ao homem. Além de chamar a atenção para a frequência e quantidade de antimicrobianos aos quais estes animais são expostos durante toda sua vida, podendo ser considerado um problema para a saúde única.(AU)

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The effects of either functional oil or antibiotic growth promoter supplementation on broiler breeders and their offspring were assessed in 2 experiments. In Experiment I, 16,400 broiler breeders (22 weeks old) were distributed into 2 experimental groups, one supplemented with 1,500 ppm of a commercial blend of functional oils (active ingredients: cashew nutshell liquid and castor oil) and the other with 500 ppm of bacitracin methylene disalicylate (BMD). Laying rates, fertility, embryonic mortality, and egg characteristics were measured from weeks 25 to 46. In Experiment II, 720 one day old male chicks, born from 42 week old breeders, from each one of the two treatments in Experiment I, were supplemented with either 10 ppm of enramycin or 1,500 ppm of the same functional oils as in Experiment I to study whether there were any maternal diet carry-over effects. Functional oils decreased embryonic mortality from 11.01% to 9.64% (P 0.03) when compared to BMD. However, a functional oil link increase in egg weight did not result in either heavier chicks or statistically significant better offspring performance. Nonetheless, a possible benefit of the functional oil supplementation on the offspring weight at 42 d cannot be excluded. The type of additive supplemented during Experiment II did not affect any performance parameters. In conclusion, functional oils could successfully replace antibiotic growth promoters in broiler breeders as embryonic mortality decreased. Finally, when functional oils were supplemented to the offspring, the performance was similar to that of a commonly used antibiotic growth promoter.

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The effects of either functional oil or antibiotic growth promoter supplementation on broiler breeders and their offspring were assessed in 2 experiments. In Experiment I, 16,400 broiler breeders (22 weeks old) were distributed into 2 experimental groups, one supplemented with 1,500 ppm of a commercial blend of functional oils (active ingredients: cashew nutshell liquid and castor oil) and the other with 500 ppm of bacitracin methylene disalicylate (BMD). Laying rates, fertility, embryonic mortality, and egg characteristics were measured from weeks 25 to 46. In Experiment II, 720 one day old male chicks, born from 42 week old breeders, from each one of the two treatments in Experiment I, were supplemented with either 10 ppm of enramycin or 1,500 ppm of the same functional oils as in Experiment I to study whether there were any maternal diet carry-over effects. Functional oils decreased embryonic mortality from 11.01% to 9.64% (P 0.03) when compared to BMD. However, a functional oil link increase in egg weight did not result in either heavier chicks or statistically significant better offspring performance. Nonetheless, a possible benefit of the functional oil supplementation on the offspring weight at 42 d cannot be excluded. The type of additive supplemented during Experiment II did not affect any performance parameters. In conclusion, functional oils could successfully replace antibiotic growth promoters in broiler breeders as embryonic mortality decreased. Finally, when functional oils were supplemented to the offspring, the performance was similar to that of a commonly used antibiotic growth promoter.(AU)

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The AmpC enzyme is normally expressed constitutively in Escherichia coli, and its overproduction confers resistance to cefoxitin. A newly reported AmpC, the extended-spectrum AmpC (ESAC), is related to resistance to cefepime, a fourth-generation cephalosporin. This enzyme presents more flexibility in the active site due to insertions, replacements, and deletions on AA sequences. Many isolates producing ESAC were reported in human clinical isolates, but E. coli ESAC producers were reported in animals only in France. The animal E. coli strains can produce this enzyme and possibly disseminate it to human and production environments. In our study, 3 strains of E. coli from milk and feces bovine samples, collected in Rio de Janeiro, Brazil, were suspected to produce ESAC. After excluding other mechanisms of resistance, the gene was sequenced to verify ESAC characteristics. These strains presented replacement of AA in omega and R2 loops, suggesting ESAC production. This is the first report to study ESAC E. coli in dairy farms in Brazil.

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The cellular mechanisms induced by elevated temperature on oocytes are not fully understood. However, there is evidence that some of the deleterious effects of heat shock are mediated by a heat-induced increase in reactive oxygen species (ROS). In this context, carotenoid antioxidants might have a thermoprotective effect. Therefore, the objective of this study was to determine the role of astaxanthin (AST) on oocyte ROS production and on the redox profile and developmental competency of cumulus-oocyte complexes (COCs) after 14h heat shock (41°C) during in vitro maturation (IVM). Exposure of oocytes to heat shock during IVM increased ROS and reduced the ability of the oocyte to cleave and develop to the blastocyst stage. However, 12.5 and 25nM astaxanthin rescued these negative effects of heat shock; astaxanthin counteracted the heat shock-induced increase in ROS and restored oocyte developmental competency. There was no effect of astaxanthin on maturation medium lipid peroxidation or on glutathione peroxidase and catalase activity in oocytes and cumulus cells. However, astaxanthin stimulated superoxide dismutase (SOD) activity in heat-shocked cumulus cells. In conclusion, direct heat shock reduced oocyte competence, which was restored by astaxanthin, possibly through regulation of ROS and SOD activity in oocytes and COCs.

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A green approach for the preparation of carbon black (CB) and electrochemically reduced graphene oxide composite (ERGO) is described based on screen printed carbon electrodes (SPCEs) fabricated on poly(ethylene terephthalate) (PET) as electrochemical sensors. This approach leads to a heterogeneous hydrophilic surface with high concentration of defect sites according to scanning electron microscopy, contact angle and Raman spectroscopy measurements. The SPCE/CB-ERGO sensor was tested with dopamine (DA), epinephrine (EP) and paracetamol (PCM), exhibiting an enhanced electrocatalytic performance compared to the bare SPCE. It displayed a wider linear range, lower limit of detection and a remarkably higher analytical sensitivity, viz. 1.5, 0.13 and 0.028 A L mol-1 for DA, EP and PCM, respectively, being also capable of simultaneous determination of the three analytes. Such high performance is demonstration that SPCE/CB-ERGO may serve as generic platform for cost-effective flexible electrochemical sensors.

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ABSTRACT The objective of this study was to evaluate the supplementation of guanidinoacetic acid (GAA) and L-arginine (L-Arg) as creatine precursors to vegetable diets on the carcass yield and meat quality of broilers subjected to two days of heat stress before slaughter. A total of 1260 broiler chicks were distributed according to a completely randomized design into four treatments with nine replicates of 35 birds each. The treatments consisted of: T1 - vegetable diet based on corn and soybean meal (control diet); T2 - control diet with the inclusion of meat meal (3%); T3 - control diet supplemented with GAA (0.08%); and T4 - control diet supplemented with L-Arg (0.8%). The birds were submitted to heat stress for two days before slaughter (from 42 to 44 days of age). The birds fed the diets supplemented with GAA or L-Arg presented heavier carcasses (p 0.0035), higher breast yield (p=0.0685), and lower of abdominal fat deposition (p=0.0508) than those fed the control diet and the control diet with meat meal. The cooking loss of the breast fillets of broilers fed the control diet supplemented with meat meal, GAA or L-Arg was lower (p 0.0068) compared with those fed the control diet. Thawing and pressure-driven breast fillet weight losses, and pH, luminosity, redness (a*value), and yellowness (b* value) values were not influenced by the treatments. When GAA is less expensive than commercially-available Arg, the dietary supplementation of GAA is more advantageous, based on the meat yield improvements observed in the present study.

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