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排序方式: 共有843条查询结果,搜索用时 15 毫秒
841.
842.
Amaury Ábrego-Gacía Héctor M.Poggi-Varaldo Vania Robles-González Teresa Ponce-Noyola Graciano Calva-Calva Elvira Ríos-Leal Daniel Estrada-Bárcenas Alfredo Mendoza-Vargas 《畜牧与生物技术杂志(英文版)》2022,(2):353-364
Methane from enteric fermentation is the gas with the greatest environmental impact emitted by ruminants.Lovastatin(Lv) addition to feedstocks could be a strategy to mitigate rumen methane emissions via decreasing the population of methanogenic archaea(MA). Thus, this paper provides the first overview of the effects of Lv supplementation, focusing on the inhibition of methane production, rumen microbiota, and ruminal fermentation.Results indicated that Lv treatment had a strong anti-methanogenic... 相似文献
843.
Lucas Silva Azevedo Incio Abreu Pestana Marcelo Gomes Almeida Wanderley Rodrigues Bastos Cristina Maria Magalhes Souza 《Ecology of Freshwater Fish》2022,31(1):72-80
Floodplain lakes are ecosystems characterised by annual flood and dry cycles. Fish ecology is influenced by the flood pulse due to the large influx of allochthonous food resources and diversification of habitats during the flood cycle, while during the dry cycle, fishes tend to be confined in reduced habitat. The aim of this study was to evaluate the seasonal variation in trophic niche width and overlap of four species—Mylossoma duriventre, Prochilodus nigricans, Cichla.pleiozona and Serrasalmus rhombeus—in an Amazonian floodplain lake. Stable isotope analyses were used to estimate trophic niche width and overlap during the flood and dry seasons. We hypothesised broader niche width for all species during the flood cycle and a higher degree of overlap between the two piscivorous fishes during the dry cycle. Isotopic niche width was 72% broader for P. nigricans, 61% for S. rhombeus and 54% for C. pleiozona during the dry cycle, which did not support our hypothesis. Core niche width overlaps were not observed between piscivorous species in either flood or dry cycle. The results indicate that seasonal variation in isotopic niche width is specific to feeding habit. Understanding how fish trophic ecology responds to changes in the hydrological regime during the seasons is crucial for sustainable fishery management in a region where many people rely heavily on fish for nutritional and economic purposes. 相似文献