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Marilene de Farias Brito Alessandra dos Santos Belo-Reis José Diomedes Barbosa Daniel Guimarães Ubiali Ana Paula de Castro Pires Elizabeth Sampaio de Medeiros Renata Pimentel Bandeira de Melo Pedro Paulo Feitosa de Albuquerque Elise Yamasaki Rinaldo Aparecido Mota 《Tropical animal health and production》2016,48(7):1497-1501
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Alessandra P.S. Salimena Carla C. Lange Cecilia Camussone Marcelo Signorini Luis F. Calvinho Maria A.V.P. Brito Cristiano A.V. Borges Alessandro S. Guimarães João B. Ribeiro Letícia C. Mendonça Roberta H. Piccoli 《Veterinary research communications》2016,40(3-4):97-106
Staphylococcus aureus is a pathogen that frequently causes mastitis in bovine herds worldwide. This pathogen produces several virulence factors, including cell-associated adhesins, toxic and cytolytic exoproteins, and capsular polysaccharides. The aim of the present study was to test for the presence of genes involved in capsular polysaccharide production and biofilm formation in S. aureus isolated from bovine mastitis samples collected from 119 dairy herds located in three different Brazilian regions, as well as to assay the production of capsular polysaccharides and biofilm, in vitro. The detection of the cap, icaAD, and bap genes was performed using PCR. The detection and quantification of capsular polysaccharide production was performed using ELISA assays. The ability of the isolates to form a biofilm was examined using the polystyrene surface of microtiter plates. All 159 S. aureus isolates investigated harboured the cap gene: 80 % carried the cap5 gene and 20 % carried the cap8 gene. Sixty-nine percent of the isolates expressed capsular polysaccharide (CP) in vitro, 58 % expressed CP5 and 11 % expressed CP8. All of the isolates harboured the icaA and icaD genes, and 95.6 % of the isolates carried the bap gene. Of the 159 isolates analysed, 97.5 % were biofilm producers. A significant association between the capsular genotype and phenotype and the amount of biofilm formation was detected: cap5/CP5 isolates tended to form more biofilm and to produce a thinner CP layer than cap8/CP8 isolates. The results indicate a high potential for pathogenicity among S. aureus isolated from bovine milk collected from three different regions in Brazil. 相似文献
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Wagner Rodrigo de Souza Nelson Geraldo de Oliveira Felipe Vinecky Ana Paula Ribeiro Marcos Fernando Basso Raphael Augusto das Chagas Noqueli Casari Brbara Andrade Dias Brito da Cunha Karoline Estefani Duarte Thaís Ribeiro Santiago Polyana Kelly Martins Carlos Eduardo Aucique‐Perez Sílvio Carlos Cristofoletti Júnior Alexandre Lima Nepomuceno Carlos Antnio Ferreira de Sousa Adilson Kenji Kobayashi Kazuo Nakashima Kazuko Yamaguchi‐Shinozaki Hugo Bruno Correa Molinari 《Journal of Agronomy and Crop Science》2019,205(6):545-553
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Victoria Asselstine Stephanie Lam Filippo Miglior Luiz F Brito Hannah Sweett Leluo Guan Sinead M Waters Graham Plastow Angela Cnovas 《Journal of animal science》2021,99(10)
Ruminant supply chains contribute 5.7 gigatons of CO2-eq per annum, which represents approximately 80% of the livestock sector emissions. One of the largest sources of emission in the ruminant sector is methane (CH4), accounting for approximately 40% of the sectors total emissions. With climate change being a growing concern, emphasis is being put on reducing greenhouse gas emissions, including those from ruminant production. Various genetic and environmental factors influence cattle CH4 production, such as breed, genetic makeup, diet, management practices, and physiological status of the host. The influence of genetic variability on CH4 yield in ruminants indicates that genomic selection for reduced CH4 emissions is possible. Although the microbiology of CH4 production has been studied, further research is needed to identify key differences in the host and microbiome genomes and how they interact with one another. The advancement of “-omics” technologies, such as metabolomics and metagenomics, may provide valuable information in this regard. Improved understanding of genetic mechanisms associated with CH4 production and the interaction between the microbiome profile and host genetics will increase the rate of genetic progress for reduced CH4 emissions. Through a systems biology approach, various “-omics” technologies can be combined to unravel genomic regions and genetic markers associated with CH4 production, which can then be used in selective breeding programs. This comprehensive review discusses current challenges in applying genomic selection for reduced CH4 emissions, and the potential for “-omics” technologies, especially metabolomics and metagenomics, to minimize such challenges. The integration and evaluation of different levels of biological information using a systems biology approach is also discussed, which can assist in understanding the underlying genetic mechanisms and biology of CH4 production traits in ruminants and aid in reducing agriculture’s overall environmental footprint. 相似文献
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da Matta CB de Souza ET de Queiroz AC de Lira DP de Araújo MV Cavalcante-Silva LH de Miranda GE de Araújo-Júnior JX Barbosa-Filho JM de Oliveira Santos BV Alexandre-Moreira MS 《Marine drugs》2011,9(3):307-318
Marine natural products have been the focus of discovery for new products of chemical and pharmacological interest. The aim of this study was to evaluate the antinociceptive activity of the methanolic (ME), acetate (AE), hexanic (HE) and chloroform (CE) extracts obtained from Caulerpa mexicana, and ME, CE and HE obtained from Caulerpa sertularioides. These marine algae are found all over the world, mainly in tropical regions. Models such as the writhing test, the hot plate test and formalin-induced nociception test were used to evaluate antinociceptive activity in laboratory mice. In the writhing test, all the extracts were administered orally at a concentration of 100 mg/kg, and induced high peripheral antinociceptive activity, with a reduction in the nociception induced by acetic acid above 65%. In the hot plate test, treatment with extracts from C. sertularioides (100 mg/kg, p.o.) did not significantly increase the latency of response, although the ME, AE and HE from C. mexicana showed activity in this model. This result suggests that these extracts exhibit antinociceptive activity. In the formalin test, it was observed that ME, AE and HE obtained from C. mexicana reduced the effects of formalin in both phases. On the other hand only CE from C. sertularioides induced significant inhibition of the nociceptive response in the first phase. To better assess the potential anti-inflammatory activity of the extracts, the carrageenan-induced peritonitis test was used to test Caulerpa spp. extracts on cell migration into the peritoneal cavity. In this assay, all extracts evaluated were able to significantly inhibit leukocyte migration into the peritoneal cavity in comparison with carrageenan. These data demonstrate that extracts from Caulerpa species elicit pronounced antinociceptive and anti-inflamatory activity against several nociception models. However, pharmacological and chemical studies are continuing in order to characterize the mechanism(s) responsible for the antinociceptive action and also to identify the active principles present in the Caulerpa species. 相似文献
100.
Luís Miguel Brito José Manuel Monteiro Isabel Mourão João Coutinho 《Journal of plant nutrition》2014,37(7):1002-1011
Fertilizer recommendations are needed to increase organic vegetable yields. Thus, organic lettuce growth and nutrient uptake was investigated in a randomized block pot experiment with twelve treatments from the factorial structure of three factors: (i) Gafsa phosphate [0 and 200 kg phosphorus pentoxide (P2O5) ha?1], (ii) compost from source separated municipal organic waste (0, 15, and 30 t ha?1) and (iii) limestone [0 and 8 t ha?1 calcium carbonate (CaCO3) equivalent]. Lettuce yield increased with compost application and a first order interaction between lime and phosphate was clear because lime partially replaced the need for phosphate. This was explained by the effect of liming on P availability in acid soils. Nitrogen (N), phosphorus (P), and potassium (K) accumulation increased in lettuces produced with compost or phosphate but only the accumulation of N was increased with lime. This compost is recommended to increase nutrient availability for organic lettuce whereas the need for phosphate fertilization may decrease with liming. 相似文献