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Aquaculture International - During the early ontogeny, the transition from endogenous (yolk protein) to exogenous feeding (artificial diets) represents a critical period linked to the...  相似文献   
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The aim of the present study was to determine whether açai oil (Euterpe oleraceae) addition in the diets of juvenile Nile tilapia (Oreochromis niloticus) in biofloc system would stimulate hepatic energy metabolism and antioxidant responses. Treatments are as follows: T0 (6%‐soybean oil), T1 (1%‐AÇAI; 5%‐SOY), T3 (3% AÇAI; 3%‐SOY) and T6 (6%‐AÇAI). In the liver, reactive oxygen species levels were significantly lower in T1, T3 and T6 than in T0, lipid peroxidation levels were significantly lower in T3 and T6, and nitric oxide levels were significantly lower in the T6 than in T0. Glutathione peroxidase activity was significantly higher in the T3 and T6 than in T0, while superoxide dismutase activity and total antioxidant capacity levels were significantly higher in the T6 than in T0. Adenylate kinase activity was significantly lower in the T6 than in T0. These results suggest that the açai oil addition in Nile tilapia diets stimulated antioxidant responses.  相似文献   
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Monoclonal antibodies (MAbs) developed against different foot-and-mouth disease virus (FMDV) vaccine strains were extensively used to study any possible antigenic variations during vaccine production in Argentine facilities. Additionally, a typing ELISA using strain specific MAbs was developed to detect potential cross contaminations among FMDV strains in master and working seeds with high specificity and sensitivity and to confirm strains identity in formulated vaccines. This assay was carried out for the South American strains currently in use in production facilities in Argentina (A24/Cruzeiro, A/Argentina/01, O1/Campos and C3/Indaial) and for the strain O/Taiwan, produced only for export to Asia. These non-cross reactive MAbs were also used to analyze the integrity of viral particles belonging to each one of the individual strains, following isolation of 140S virions by means of sucrose density gradients from the aqueous phase of commercial polyvalent vaccines. Antigenic profiles were defined for FMDV reference strains using panels of MAbs, and a coefficient of correlation of reactivity with these panels was calculated to establish consistent identity upon serial passages of master and production seeds. A comparison of vaccine and field strain antigenic profiles performed using coefficients of correlation allowed the rapid identification of two main groups of serotype A viruses collected during the last FMD epidemic in Argentina, whose reactivity matched closely to A/Argentina/2000 and A/Argentina/2001 strains.  相似文献   
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Plieninger  Tobias  Torralba  Mario  Hartel  Tibor  Fagerholm  Nora 《Landscape Ecology》2019,34(7):1565-1581
Context

Around 30% of European agricultural landscapes are classified as high nature value (HNV) farmlands. Current policies emphasize the multifunctionality of these landscapes, but little is known about the positive and negative associations of multiple ecosystem services within HNV farmland.

Objectives

This study aims to identify perceived ecosystem services synergies, trade-offs, and bundles in agricultural landscapes of HNV from a socio-cultural perspective.

Methods

We performed a participatory mapping survey of 10 ecosystem services categories among 2301 rural residents in 13 European sites. We analyzed bivariate synergies and trade-offs between perceived ecosystem services through nonparametric correlation analyses. Spatial bundles of perceived ecosystem services were identified through hierarchical cluster analysis. Multinomial logit models were used to assess the influence of land cover on generating associations of ecosystem services.

Results

We find two strong and 16 moderate synergies of perceived ecosystem services (out of 46 possible ecosystem services pairs), mainly among different cultural ecosystem services. We do not reveal moderate or strong trade-offs. We identify five spatial bundles of ecosystem services, termed “Ecosystem services coldspots”, “Wild harvesting ranges”, “Nature areas”, “Recreational spaces”, and “Ecosystem services hotspots”. Of all land-cover co-variates, natural areas, urban areas, and roads have the strongest explanatory power.

Conclusions

Our study complements prevailing biophysical and economic analyses of ecosystem services synergies, trade-offs and bundles by a spatially explicit, socio-cultural perspective. We conclude that socio-cultural mapping of ecosystem services is useful for understanding the perceived multifunctionality of a landscape.

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Reference ranges for triglycerides, insulin, cortisol, and adrenocorticotropic hormone (ACTH) are used in diagnosing hyperlipemia and pituitary pars intermedia dysfunction (PPID) in the donkey. Values are currently compared to reference ranges of the horse so as to diagnose disease. Previous studies found differences between hematological, serum biochemical, and hormone values of the horse and donkey. We suspected that similar differences existed between horse and donkey triglyceride, insulin, cortisol, and ACTH levels. Blood samples were drawn from 44 healthy mammoth donkeys and 1 miniature donkey, ranging in age from 3 weeks to 21 years, and varying in sex and pregnancy status. All but one donkey scored 3 of 5, “ideal,” body condition scoring. Samples were tested for triglycerides, insulin, cortisol, and ACTH levels. A marked difference was found between horse and donkey normal values for triglycerides, insulin, and ACTH. The mean values and standard deviation in the tested population were 66.4 ± 34.2 mg/dL for triglycerides, 2.1 ± 2.05 μU/mL for insulin, and 66.7 ± 20.7 pg/mL for ACTH. The reference ranges in the horse are 14–77 mg/dL for triglycerides, 4.9–45.5 μU/mL for insulin, and 18.7 ± 6.8 pg/mL for ACTH. Cortisol levels were similar in the two species, a 4.0 ± 1.2 μg/dL for donkeys being within the reference range for the horse, 2.9–6.6 μg/dL. Values were not correlated to age. The sample size prevented us from determining any correlation according to sex or pregnancy status. Differences between horse and donkey triglyceride and ACTH values may be significant for accurately diagnosing and treating hyperlipemia and PPID, respectively, in the donkey.  相似文献   
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