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671.
Effects of dietary soy isoflavones on estrogenic activity,cortisol level,health and growth in rainbow trout,Oncorhynchus mykiss 下载免费PDF全文
Maria Rita Pastore Elena Negrato Carlo Poltronieri Giuseppe Barion Maria Messina Francesca Tulli Cristina Ballarin Lisa Maccatrozzo Giuseppe Radaelli Daniela Bertotto 《Aquaculture Research》2018,49(4):1469-1479
Soy isoflavones (the phytoestrogens genistein, daidzein and glycitein) may act as estrogen receptor agonists or antagonists. The aim of this study was to examine the effect of dietary isoflavones on growth, reproduction and health in rainbow trout (Oncorhynchus mykiss). Rainbow trout fed three experimental diets containing different concentrations of isoflavones (0, 500 and 1,500 ppm). Growth, estrogenic activity, plasma estradiol levels, gonadal development, state of stress and histological changes in selected tissues were evaluated at the end of 70 days. Neither growth performance nor the relative mRNA levels of Insulin Growth Factor I (igf‐I) in the liver were influenced by different levels of dietary isoflavones. Plasma and liver vitellogenin (VTG) protein levels and plasma 17‐β‐estradiol (E2) were unaffected by treatments, although the correlation between plasma levels of E2 and VTG densitometry values was significant (p < .05). The fish gonadosomatic index (GSI) did not significantly differ among the three experimental groups but correlated with plasma VTG densitometry values (p < .05). Plasma, muscle and fin cortisol concentrations fell within the normal welfare range and were not correlated with isoflavone levels. Histologically, the distal intestine showed a normal morphology with well‐differentiated enterocytes and in the liver hepatocytes were also normal. A supranuclear accumulation of lipid droplets in enterocytes and some lipid droplets in hepatocytes were observed in all tested groups, suggesting an impact of basal dietary lipid on transport/metabolism of fat in the fish. Overall, the present results suggest that the doses of isoflavones tested do not compromise rainbow trout reproduction, growth and health. 相似文献
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Rita Redaelli Viviana Del Frate Silvia Bellato Giovanna Terracciano Roberto Ciccoritti Christoph U. Germeier Ester De Stefanis Daniela Sgrulletta 《Journal of Cereal Science》2013
A growing interest in oat (Avena ssp.) soluble fibre (β-glucan) is related to its role in the promotion of human health, and to its utilization in the production of functional foods with increased health benefits. Genetic variability and environmental conditions can exert significant effects on the grain β-glucan content. In this study 658 European oat genotypes grown in different environments in 2008 or 2009 within the European Project “Avena genetic resources for quality in human consumption” were analysed for total β-glucan content; the soluble fraction of β-glucan was also determined in a sub-set of 165 samples. Total β-glucan content ranged from 2.85 to 6.77% d.m. and the soluble fraction from 2.05 to 5.29% d.m. The estimated percentage of the soluble fraction ranged from 50.7 to 87.0%. β-glucan content and solubility were significantly influenced by both genotype and growing environment. Hierarchical cluster analysis allowed accessions with similar β-glucan compositions to be grouped. The accessions with the highest contents of both fractions included Avena sativa varieties from several countries and wild species. Finally, the data obtained were used to develop a NIRS calibration equation to predict the contents of total and soluble β-glucan in both naked and husked genotypes. 相似文献
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Nolen-Walston R Bedenice D Rodriguez C Rushton S Bright A Fecteau ME Short D Majdalany R Tewari D Pedersen D Kiupel M Maes R Del Piero F 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):846-852
BACKGROUND: Eastern equine encephalitis (EEE) virus is a mosquito-borne togavirus (alphavirus) that causes severe (often fatal) encephalitis in many mammalian species, but it has not been reported previously in South American camelids. Hypothesis: South American camelids can become naturally infected with EEE virus and show encephalitic signs similar to those observed in other affected species. ANIMALS: Nine cases (8 alpacas and 1 llama, aged 3.5 weeks to 12 years) were identified; 4 of 9 were 510 weeks old. All cases were from the East Coast of the United States and presented in late summer and fall. METHODS: A retrospective study was performed to include confirmed cases of EEE in camelids in North America before 2006. RESULTS: Eight of nine (89%) camelids died or were euthanized in extremis, with the mean time to death of 2 days. Clinical signs were consistent with encephalitis and included fever, lethargy, ataxia, seizures, recumbency, torticollis, opisthotonus, and vestibular signs. No consistent hematologic abnormalities were identified, and cerebrospinal fluid contained an increased protein concentration in the single camelid analyzed. No successful therapy was identified. EEE was confirmed by alphavirus detection by using immunohistochemistry (IHC) and polymerase chain reaction (PCR) in the central nervous system (CNS) and by serology. Findings included polioencephalitis with lymphocytic perivascular cuffing; neutrophil infiltration; gliosis; neuron satellitosis; necrosis; and edema, with intracytoplasmic alphavirus within neurons and glial cells. No virus was detected in extraneural tissues. CONCLUSIONS AND CLINICAL IMPORTANCE: In endemic areas, EEE should be considered a differential diagnosis for young and adult camelids with CNS disease. Brain histopathology with indirect IHC or PCR is diagnostic. 相似文献
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Contrary to humans, most ovarian tumors in other species do not arise from the ovarian surface epithelium but are of follicular‐, stromal‐ or germ‐cell origin. One of the few species where ovarian cancer arises from the ovarian surface epithelium (OSE) is chicken (Gallus domesticus). Little is known about the morphology of the OSE in other avian species. In our study we analyzed the OSE morphology of Japanese quail (Coturnix japonica) using ultrastructural and histochemical techniques. Carbohydrate residues have been studied by using a panel of fluorescein isothiocyanate labeled lectins. Japanese quails are commonly used animal models in biomedical research as their housing is comparatively inexpensive and they show a short generation interval. Our ultrastructural and histochemical results demonstrate that the quail ovarian surface epithelium shows characteristic features which resemble the epithelia of both chicken and human. Additionally, the ovarian surface epithelium of the Japanese quail contains cytokeratin as well as vimentin intermediate filaments in their cytoplasm. Therewith and among other parts the quail OSE shows many characteristic features also seen in those of humans, which may qualify quail's ovary as a potential animal model for human ovarian carcinomas. 相似文献
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Enrico Bigliardi Carla Bresciani Daniela Callegari Francesco Di Ianni Giorgio Morini Enrico Parmigiani Ezio Bianchi 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(2):267-271
Insulin resistance (IR) in dogs is suspected when hyperglycemia is present despite administration of insulin doses greater than 1.0 to 1.5 UI/kg. IR is caused by increases in counter regulatory hormones concentrations (glucagon, glucocorticoids, catecholamines and growth hormone). This study was conducted to investigate the use of aglepristone (RU 46534), a P4 receptor antagonist, for the treatment of IR diabetes mellitus in bitches during the luteal phase. All animals were treated with porcine insulin zinc suspension (Caninsulin) and aglepristone (Alizin) 10 mg/kg subcutaneously at day 1, 2, 9 and 17 from diagnosis. At day 5, no significant variation in glycemia was shown. At day 12 and 20, serum glucose concentrations were significant lower (p < 0.05). From day 12 the insulin dose was reduced to 0.8 IU BID. Insulin was reduced in the following weeks and glycemia was controlled. 相似文献
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Daniela Klein-J?bstl Tim Arnholdt Franz Sturmlechner Michael Iwersen Marc Drillich 《Acta veterinaria Scandinavica》2015,57(1)