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排序方式: 共有617条查询结果,搜索用时 15 毫秒
611.
Gabriela Velasco-Blanco Ana Denise Re Fernando Daz Leonardo Ibarra-Castro Maria Isabel Abdo-de la Parra Luz Estela Rodrguez-Ibarra Carlos Rosas 《International Aquatic Research》2019,11(2):187-197
The clownfish Amphiprion ocellaris is widely distributed in the coral reef ecosystems of tropical and subtropical regions of the West Indo Pacific, an area that hosts economically valuable species, and, thus, a suitable candidate for warm water aquaculture. This study determined the preferred temperature, critical threshold limits, represented by critical thermal maximum and critical thermal minimum, thermal window width, and aerobic metabolic scope of A. ocellaris clownfish acclimated to 20, 23, 26, 29, 32, and 35 °C. A positive response (P < 0.05) occurred when the preferred temperature significantly increased with increasing acclimation temperature. The preferred temperature obtained graphically was 30.0 °C. Acclimation temperature significantly affected the thermal tolerance which increased with acclimation temperature. The thermal window calculated for A. ocellaris was 301.5 °C2. The thermal metabolic scope obtained in animals acclimated at the interval from 23 to 32 °C (P > 0.05) had a mean value of 4240.8 mg O2 h−1 kg−1 w.w., revealing that A. ocellaris is a eurythermal species with a range of optimal physiological performance that closely matches the environmental conditions where it can be farmed. Therefore, the highest value of the thermal aerobic scopes corresponded to the intervals of the preferred temperature obtained for A. ocellaris. These results may partially explain their worldwide distribution pattern, as well as their aquaculture potential in tropical regions. 相似文献
612.
Rodolphe E Gozlan Demetra Andreou Takashi Asaeda Kathleen Beyer Rachid Bouhadad Dean Burnard Nuno Caiola Predrag Cakic Vesna Djikanovic Hamid R Esmaeili Istvan Falka Duncan Golicher Akos Harka Galina Jeney Vladimír Kováč Jiří Musil Annamaria Nocita Meta Povz Nicolas Poulet Tomas Virbickas Christian Wolter A Serhan Tarkan Elena Tricarico Teodora Trichkova Hugo Verreycken Andrzej Witkowski Chun Guang Zhang Irene Zweimueller J Robert Britton 《Fish and Fisheries》2010,11(4):315-340
In recent years, policy‐makers have sought the development of appropriate tools to prevent and manage introductions of invasive species. However, these tools are not well suited for introductions of non‐target species that are unknowingly released alongside intentionally‐introduced species. The most compelling example of such invasion is arguably the topmouth gudgeon Pseudorasbora parva, a small cyprinid species originating from East Asia. A combination of sociological, economical and biological factors has fuelled their rapid invasion since the 1960s; 32 countries (from Central Asia to North Africa) have been invaded in less than 50 years. Based on a combination of monitoring surveys (2535 populations sampled) and literature reviews, this paper aims to quantify and characterise important invasion parameters, such as pathways of introduction, time between introduction and detection, lag phase and plasticity of life history traits. Every decade, five new countries have reported P. parva introduction, mainly resulting from the movement of Chinese carps for fish farming. The mean detection period after first introduction was 4 years, a duration insufficient to prevent their pan‐continental invasion. High phenotypic plasticity in fitness related traits such as growth, early maturity, fecundity, reproductive behaviour and the ability to cope with novel pathogens has predisposed P. parva to being a strong invader. The Pseudorasbora parva invasion has provided quantitative data for the development of 1) early warning systems across different spatial scales; 2) rapid eradication programmes prior to natural spread in open systems and 3) sound risk assessments with emphasis on plasticity of life history traits. 相似文献
613.
Effect of Water Temperature on Reproductive Tract Condition of Penaeus setiferus Adult Males 总被引:2,自引:0,他引:2
Cristina Pascual Evangelina Valera Cristina Re-Regis Gabriela Gaxiola Adolfo Sanchez Laida Ramos Luis A. Soto Carlos Rosas 《Journal of the World Aquaculture Society》1998,29(4):477-484
Abstract— This study was conducted to determine the effect of water temperature on male reproductive tract degenerative syndrome (MRTDS) and male reproductive system melanization (MRSM) in Penaeus setiferus , and to evaluate the effect of water temperature on spermatophore regeneration time and sperm quality in electrically ejaculated adult males. Variation in sperm quality, gonadosomatic index, and histological changes in the reproductive system were used to assess reproductive tract changes in the first experiment. Sperm quality and regeneration time were measured before and after successive regenerations in the second experiment. Sperm quality was stable when shrimp were held at 26 C for 30 d but was reduced when shrimp were held at 30 C. Reproductive tissues of 20% of the shrimp held at 30 C were melanized to some degree but tissue melanization was found in only 2.5% of the shrimp held at 26 C. Spennatophore regeneration time was also affected by temperature. Average times for first spermatophore regeneration were 192 h at 25 C, 152 h at 30 C, and 144 h at 33 C. Sperm quality of regenerated shrimp was not affected at 25 C but was reduced for regenerated animals held at 33 C. Based on these results, we recommend a water temperature between 25 and 27 C to obtain adequate spermatophore regeneration and to maintain healthy male P. setiferus broodstock for at least 30 d. 相似文献
614.
Autochthonous probiotic Lactobacillus sp. in the diet of bullfrog tadpoles Lithobates catesbeianus improves weight gain,feed conversion and gut microbiota
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S.A. Pereira G.T. Jerônimo N. da Costa Marchiori H.M. de Oliveira M.S. Owatari G.F.A. Jesus P. Garcia F. do Nascimento Vieira M.L. Martins J.L.P. Mouriño 《Aquaculture Nutrition》2017,23(5):910-916
Dietary supplementation with probiotics in animal production is an alternative to antibiotics. In frog culture, studies involving native strains of probiotic bacteria and their effects on the performance and intestinal histology of farmed animals are scarce. Therefore, this study aimed to evaluate a diet supplemented with Lactobacillus sp. in tadpoles of Lithobates catesbeianus. This randomized test was performed with two dietary treatments: non‐supplemented control diet and diet supplemented with Lactobacillus sp., with nine replications. The growth performance of Lactobacillus sp., including its bacterial enzymatic activity and stability in feed, as well as colonization and histology of the intestinal tract, was evaluated after 42 days of experimentation. Animals fed with a supplemented diet showed higher weight gain and concentration of lactic acid bacteria in the gut and lower feed conversion. No significant difference was observed in survival, total heterotrophic bacterial count or histological change in the gut between the two treatments. The Lactobacillus sp. strain was able to colonize the intestinal tract and feed and remain at a high concentration of 107 and 106 CFU g?1, respectively. It produced several enzymes, which might have contributed to the greater weight gain and lower feed conversion in the supplemented animals, thus demonstrating its probiotic potential for use as a dietary supplement in bullfrog tadpoles. 相似文献
615.
Monika Krzewska Gabriela Gołębiowska-Pikania Ewa Dubas Marta Gawin Iwona Żur 《Euphytica》2017,213(8):192
For a better understanding of the physiological background of microspore embryogenesis (ME), the protein profile was analyzed in four winter triticale DH lines, which show extremely different embryogenic potential. The analysis were conducted with anthers at the phase of development optimal for ME induction and then after low temperature (LT, 3 weeks at 4 °C) ME-inducing tillers treatment. The sub-proteome of anthers was mapped by two-dimensional gel electrophoresis (2-DE). The protein species significantly more abundant (at least 2-fold) in responsive DH lines after LT treatment were chosen for identification by MALDI-TOF/TOF analysis. In total, 31 protein species were successfully identified as involved in the determination of microspore competence, stress response and in the regulation of ME induction. Microspore competence required sufficient energy supply and efficient system of cell protection that determine survival under prolonged LT stress treatment. LT stress was associated with increased accumulation of proteins typical for cell defence against oxidative stress (e.g., l-ascorbate peroxidase), chaperons (e.g., HSP70) and other enzymes/factors ensuring protein biosynthesis, stability and active cell divisions. Also here, effective cell defence required undisturbed energy supply. Among proteins that accumulated differentially in accordance with microspore embryogenic potential again the most important role seems to be played by the enzymes ensuring energy production and determining ability of plant stress adaptation. Two protein species (enolase, 12S storage protein), proposed earlier as candidates for markers of embryogenesis in other in vitro plant culture systems confirmed their utility for triticale anther cultures. 相似文献
616.
Paulo C sar DE FACCIO CARVALHO Jean V ctor SAVIAN Tomas DELLA CHIESA William DE SOUZA FILHO Jos Alfredo TERRA Priscila PINTO Amanda POSSELT MARTINS Sebastian VILLARINO J lio Kuhn DA TRINDADE Pedro Arthur DE ALBUQUERQUE NUNES Gervasio PI EIRO 《农业科学与工程前沿(英文版)》2021,8(1):97-110
617.