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791.
Change in Sox9 protein localization through gonad development in Russian sturgeon (Acipenser gueldenstaedtii) 下载免费PDF全文
Maciej Kamaszewski Aleksandra Gosk Marek Skrobisz Teresa Ostaszewska 《Aquaculture Research》2017,48(6):3111-3120
The Russian sturgeon is a highly prized species reared in aquaculture. The process of gonad development in this critically endangered species is poorly understood. The aim of this study was to describe the localization of Sox9 protein during gonad development of the Russian sturgeon from the day of hatching to the 1440 day post hatching (dph). The larvae at age 1, 10, 25 dph and prepared gonads of 300, 720, 1440 dph individuals were immunohistochemistry‐stained for Sox9 detection. Sox9‐positive regions were detected in larvae in primordial germ cells cytoplasm. Analysis of 300 dph sturgeon gonads revealed the presence of the Sox9 protein in cytoplasm of some oocytes in the chromatin nucleus stage. In testes at 720 dph, Sox9 was observed in the cytoplasm of type A and early B spermatogonias. In the ovaries, Sox9 was observed in the cytoplasm of diplotene oocytes and prefollicular cells. In testes of 1440 dph sturgeon, Sox9 was present in the nucleus of the spermatocytes and in types A and B spermatogonias cytoplasm. Analysis of ovaries at 1440 dph reveals multiple diplotene oocytes with a Sox9‐positive cytoplasm. Furthermore, in 720 and 1440 dph, sturgeon presence of intersexual gonads was detected. In intersex gonads, Sox9 was observed in the cytoplasm of diplotene oocytes and type A spermatogonias. This study may be the first attempt to determine Sox9 protein localization during ontogenesis of the Russian sturgeon. Localization of Sox9 protein may become a useful marker of the maturation level in testis of the Russian sturgeon. 相似文献
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793.
Francisco Encina‐Montoya Rolando Vega‐Aguayo Alfonso Mardones‐Lazcano Teresa Rueda Alfredo Tello 《Aquaculture Research》2011,42(6):835-843
Galaxias maculatus is an osmeriform native fish of the Southern Hemisphere, in which the crystalline larvae is considered as a luxury delicacy, for this reason, it has been commercially exploited in Chile, Argentina and New Zealand. However, the fisheries have been rapidly decreasing due to the overexploitation and the predation of introduced species. Because of these events, there is a need to determine a carrying capacity for an intensive fish culture. In order to optimize stocking densities for fish culture, this paper proposes objectives to determine oxygen consumption (OC) rates, dissolved oxygen concentrations that produce signs of hypoxia and the average time elapsed between food intake and peak OC in G. maculatus. In the oxygen experiments under routine metabolism conditions, we found that G. maculatus adults and whitebait showed signs of asphyxia at dissolved oxygen concentrations between 1.3 and 2.2 mg L?1 and that adults tolerated dissolved oxygen levels as low as 1.3 mg L?1. The results showed that G. maculatus individuals with an average weight of 0.04 g consumed 0.048 mg O2 h?1, whereas individuals with an average weight of 1.4 g consumed 0.345 mg O2 h?1. Galaxias maculatus increased the OC rate by 31%, from 0.39 to 0.51 mg O2 h?1 g?1, occurring 14 min after food intake. The carrying capacities for industrial cultures of G. maculatus, were estimated using an allometric equation (OC=0.2363 ×W 0.612 ), a water flow rate of 1 m3 h?1 and an input oxygen concentration of 10 mg L?1 at 12 °C. The density culture of whitebait (4 g) can be allowed to reach 8–11 kg m?3; therefore, these stocking densities reduce the risk of hypoxia and mortality, ensuring the appropriate growth and feed conversion rates. 相似文献
794.
Margherita Santoni Leonardo Verdi Shamina Imran Pathan Marco Napoli Anna Dalla Marta Francesca Romana Dani Gaio Cesare Pacini Maria Teresa Ceccherini 《Soil Use and Management》2023,39(1):588-605
The implementation of environmentally friendly agricultural policies has increased the need to compare agricultural aspects of conventional (CON) and organic farming (ORG) systems. The objective of the present work was to compare the effects of an organic and conventional long-term experiment on bacterial and fungal biomass and activity, as well as soil CO2 emission and readily available nitrogen forms in a soil cultivated with Helianthus annuus L. The microbial biomass was more active and abundant in ORG as well as soil CO2 emission. Despite being less abundant, fungi were more active than bacteria in both ORG and CON experiments. 16S rRNA gene sequencing showed that the ORG treatment had a significantly greater bacterial richness than CON. Cyanobacteria, Actinobacteria and Proteobacteria were the most abundant phyla contributing more than others to the differences between the two systems. Moreover, the soil and content was not significantly different between ORG and CON, while was less in ORG. ORG sunflower yield was significantly less compared with CON. While much remains to be discovered about the effects of these agricultural practices on soil chemical properties and microbial diversity, our findings may contribute to this type of investigation. 相似文献
795.
Sara Belluco Giuseppe Marano Thibaut Lurier Giancarlo Avallone Chiara Brachelente Stefano Di Palma Roberta Rasotto Kerstin Baiker Andreas Beineke Anna Oevermann Frauke Seehusen Fabiano José Ferreira de Sant'Ana Patrizia Boracchi Martí Pumarola Maria Teresa Mandara 《Veterinary and comparative oncology》2023,21(4):685-699
Canine meningiomas are currently graded using the human grading system. Recently published guidelines have adapted the human grading system for use in dogs. The goal of this study was to validate the new guidelines for canine meningiomas. To evaluate the inter-observer agreement, 5 veterinary surgical pathologists graded 158 canine meningiomas following the human grading system alone or with the new guidelines. The inter-observer agreement for histologic grade and each of the grading criteria (mitotic grade, invasion, spontaneous necrosis, macronucleoli, small cells, hypercellularity, pattern loss and anaplasia) was evaluated using the Fleiss kappa index. The diagnostic accuracy (sensitivity and specificity) was assessed by comparing the diagnoses obtained with the 2 grading systems with a consensus grade (considered the reference classification). The consensus histologic grade was obtained by agreement between 4 experienced veterinary neuropathologists following the guidelines. Compared with the human grading alone, the canine-specific guidelines increased the inter-observer agreement for: histologic grade (κ = 0.52); invasion (κ = 0.67); necrosis (κ = 0.62); small cells (κ = 0.36); pattern loss (κ = 0.49) and anaplasia (κ = 0.55). Mitotic grade agreement remained substantial (κ = 0.63). The guidelines improved the sensitivity in identifying grade 1 (95.6%) and the specificity in identifying grade 2 (96.2%) meningiomas. In conclusion, the new grading guidelines for canine meningiomas are associated with an overall improvement in the inter-observer agreement and higher diagnostic accuracy in diagnosing grade 1 and grade 2 meningiomas. 相似文献
796.
Teresa De Pilli Roma Giuliani Barbara F. Carbone Antonio Derossi Carla Severini 《Cereal Chemistry》2005,82(5):494-498
Doughs made from wheat and almond flours, water, and five types of emulsifiers commonly used in confectionary and bakery products (soy lecithin, sucrose esters, mono‐glycerides, mono‐ and di‐glycerides of fatty acids, and diacetyl tartaric acid esters of monoglycerides [DATEM]) were studied. To evaluate the additive ability to retain the fatty fraction during the extrusion process, electrical conductivity was measured and fat loss (%) that occurs during extrusion processing was determined. The electrical conductivity measurements showed that the lower and better concentration of soy lecithin and mixed mono‐ and di‐glycerides of fatty acids to obtain an oil‐water emulsion was 0.2 g/100 g of dough, while for sucrose esters and mono‐glycerides of fatty acids, it was 0.7 g/100 g of dough. No efficacy for DATEM was observed. The fat loss results showed that sucrose esters were the most suitable emulsifiers for retaining the fatty fraction during extrusion processing, even at a very low amounts (2 g/kg of dough). 相似文献