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871.
Anna Fickler Claudia Torno Stefanie Staats Gerald Rimbach Carsten Schulz 《Aquaculture Research》2019,50(8):2170-2180
Phytoestrogens are putatively able to enhance the biosynthesis of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), but have also been shown to affect fish growth dose dependently. The aim of the present study was to identify a concentration for the phytoestrogen genistein and the phytoestrogen metabolite equol that further increases the endogenous biosynthesis of EPA and DHA without impairing fish growth. Juvenile rainbow trout (87.2 ± 0.3 g) were fed seven diets on a fixed ratio for 8 weeks. A vegetable oil‐based diet served as a control diet and was supplemented with equol (EQ) and genistein (G), respectively, at 0.1%, 0.2% and 0.3% of feed dry matter (1, 2 and 3). Growth and nutrient composition of whole body homogenates were not affected by dietary treatments. EPA and DHA levels in liver, fillet and whole body samples were not significantly increased by EQ and G diets. Fish fed EQ diets showed dose dependently increased liver weights and C18:0 liver levels, indicating estrogen‐like effects at increased dietary dosages. In conclusion, the utilization of equol and genistein in plant oil‐based diets in order to enhance the biosynthesis of EPA and DHA seems not reasonable in rainbow trout. 相似文献
872.
Rebecca Veronesi Marina Morach Ella Hübschke Claudia Bachofen Roger Stephan Magdalena Nüesch‐Inderbinen 《Zoonoses and public health》2021,68(1):8-11
Hepatitis E virus (HEV) is the causative agent of an acute and in most cases self‐limiting hepatitis. Of the four major HEV genotypes that infect humans, genotype 3 and 4 are zoonotic and have been identified in humans but predominantly in pigs and wild boar, which are considered the main reservoirs. However, the known host range of zoonotic HEV may be increasing to comprise additional species, including companion animals. Several studies have identified contact with dogs as a risk factor for HEV infection in humans, yet information on the occurrence of HEV in Swiss dogs is lacking. To examine a possible risk of exposure, this study was designed to assess the seroprevalence of HEV in 84 Swiss dogs. Serum and plasma samples collected from four veterinary clinics were screened for HEV‐specific antibodies by HEV‐antibody ELISA test kit. In addition, information of 22 dogs regarding the country of origin, the type of dog feed and any history of hunting was recorded. Samples from seropositive animals were also screened for the presence of HEV RNA by quantitative real‐time RT‐PCR (qRT‐PCR). Overall, 38% (32 of 84) of the dogs tested seropositive for anti‐HEV, indicating exposure to HEV. Among the 22 dogs for which information was available, HEV‐specific antibodies were detected in three of five dogs that were born abroad, in one of two dogs that were fed a raw meat‐based diet, and in one hunting dog. No viral RNA could be detected in any of the serum and plasma samples; thus, the genotype of the strains remained undetermined. This study provides further evidence for canine exposure and susceptibility to HEV and highlights the need to further assess the risks of HEV transmission to humans with contact to dogs. 相似文献
873.
Migration of bisphenol A (BPA) from epoxy can coatings to jalapeño peppers and an acid food simulant
Munguia-Lopez EM Peralta E Gonzalez-Leon A Vargas-Requena C Soto-Valdez H 《Journal of agricultural and food chemistry》2002,50(25):7299-7302
Effects of heat processing, storage time, and temperature on migration of bisphenol A (BPA) from an epoxy type can coating to an acid food simulant and jalape?o peppers were determined. Commercial jalape?o pepper cans (8 oz, dimensions 211 x 300) were stored at 25 degrees C for 40, 70, and 160 days. A solution of 3% acetic acid was canned in 211 x 300 cans from the same batch used for jalape?o peppers. Heat processing was applied to two-thirds of the cans, and the remaining cans were not heat processed. Cans were stored at 25 and 35 degrees C for 0, 40, 70, and 160 days. Results showed that there is a minimal effect of heat treatment. An effect of storage time on migration of BPA during the first 40 days at 25 degrees C was observed. An increase on migration of BPA was observed with storage time at 35 degrees C. The highest level of migration was 15.33 microg/kg of BPA at 160 days at 35 degrees C. A correction factor of approximately 0.4 was calculated for migration under simulating conditions of storage compared to the real ones. The highest level of BPA found in jalape?o peppers cans, surveyed from three supermarkets, was 5.59 +/- 2.43 microg/kg. Migration of BPA, performed according to the European and Mercosur conditions, was 65.45 +/- 5.29 microg/kg. All the migration values found in this study were below those legislation limits (3 mg/kg). 相似文献
874.
Migena Gjoni Gündemir Tomasz Szara Constantin Spataru Ismail Demircioglu Bernard Turek Georgios Petrovas Mihaela Claudia Spataru 《Anatomia, histologia, embryologia》2023,52(2):190-196
The anatomy of the sternum in birds varies according to their habitats and type of locomotion. In particular, the carina sterni manifest different shape variations. In this study, the shape of the carina sterni was investigated by means of geometric morphometrics. Birds of different types of locomotion were used in the study: flying, swimming, and terrestrial. Ducks and chickens show a wider variety of shapes. Pigeons are the species with the least differences. The margo cranialis carinae in a turkey is the flattest compared to other species. In chickens, the apex carinae is more caudally than the base of the carina sterni. The margo cranialis of the carina sterni in ducks is concave. The differences in centroid size and shape differences between species collectively are statistically significant (p < 0.0001). The most distinct shape contrast is between the duck and turkey (p: 0.0003). Form differences between the ducks and geese as well as between the chicken and turkey are statistically insignificant. There is less variation in the shape of the carina sterni among avian species representing the same type of locomotion. Although there are many comparative morphological and morphometric studies of birds, shape analysis studies revealing the interspecific differences and similarities of the sternum are very limited. Morphology of the carina sterni can be useful in taxonomic investigations. 相似文献
875.
Lydia X. Gan Claudia L. Y. Tan Amirrudin B. Ahmad Yixiong Cai Darren C. J. Yeo 《水产资源保护:海洋与淡水生态系统》2023,33(1):89-101
- Commodity-driven forest conversion represents one of the most severe threats to freshwater biodiversity in Southeast Asia, notably causing population declines and the extinction of freshwater fish species.
- Although a variety of freshwater taxa are likely to be adversely affected by forest conversion, little is known about the impact on ecologically and economically important invertebrates such as decapod crustaceans.
- This study evaluated the impact of forest conversion and land-use change on freshwater Macrobrachium shrimp species, using species richness, abundance, and environmental data collected from 20 streams across southern Peninsular Malaysia. Streams were located in three types of landscape: forest; oil palm plantation; and mixed land use, comprising young secondary forest, small-scale plantations, patches of open and sparsely vegetated areas, and agricultural fields and clearings.
- Generalized linear models showed that even incomplete change from forest habitats to mixed land use and oil palm plantation resulted in significantly lower Macrobrachium native species richness and higher non-native species abundance. Native species richness was positively correlated with canopy cover, leaf litter, substrate size, and dissolved oxygen, and was negatively correlated with water temperature and conductivity. Native species richness was also negatively correlated with non-native species abundance, with non-native species abundance increasing along the human disturbance gradient.
- These results highlight the need for riparian habitat protection to conserve native Macrobrachium and limit the spread of non-native species. A management priority should be to maintain or restore optimum instream habitat conditions for shrimps, which would also benefit fish and other benthic macroinvertebrates. Suitable riparian management requires substantial support and funding from multiple stakeholders, but it can be aligned with other catchment-based strategies to optimize the use of limited resources available for freshwater biodiversity conservation.