Control of bovine mastitis: old and recent therapeutic approaches

Mastitis is defined as the inflammatory response resulting of the infection of the udder tissue and it is reported in numerous species, namely in domestic dairy animals. This pathology is the most frequent disease of dairy cattle and can be potentially fatal. Mastitis is an economically important pathology associated with reduced milk production, changes in milk composition and quality, being considered one of the most costly to dairy industry. Therefore, the majority of research in the field has focused on control of bovine mastitis and many efforts are being made for the development of new and effective anti-mastitis drugs. Antibiotic treatment is an established component of mastitis control programs; however, the continuous search for new therapeutic alternatives, effective in the control and treatment of bovine mastitis, is urgent. This review will provide an overview of some conventional and emerging approaches in the management of bovine mastitis infections.F. Gomes acknowledge the financial support of the Portuguese Foundation for Science and Technology through the Grant SFRH/BPD/84488/2012 and for financial support to the CEB research center

Screening and comparative study of in vitro antioxidant and antimicrobial activities of ethanolic extracts of selected Vietnamese plants

This study aimed to screen the in vitro antioxidant and antimicrobial activities of ethanolic extracts from 20 plants and three herbal commercial products empirically used for aquaculture improvement in Vietnam. The results of 2,2-diphenyl-1-pycrylhydrazyl (DPPH) radical scavenging assays showed that Phyllanthus amarus extract was the strongest antioxidant, followed by four extracts in the subsequent order: Piper betle > Psidium guajava > Euphorbia hirta > Mimosa pudica. These five plant extracts were very active in a DPPH radical scavenging assay with concentrations needed to scavenge half of the DPPH (IC50) below 30 µg/mL. Seven plant extracts showed an IC50 ranging from 31.9 to 59.7 µg/mL, while eleven extracts showed an IC50 above 70 µg/mL. A positive association was found between phenolic content (expressed as gallic acid equivalents) and antioxidant activity of the plant extracts. Concerning in vitro antimicrobial activities, P. amarus extract showed the highest activity against two different strains of Aeromonas hydrophila as demonstrated by its low minimal inhibitory concentration (MIC) of 156 and 625 µg/mL, respectively; whereas, P. betle displayed a moderate activity against Edwardsiella ictaluri with a MIC value of 625 µg/mL. Tannins were observed as significant factors contributing to antioxidant and antimicrobial properties of the plant extracts tested