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151.
Ken Overturf Roger L. Vallejo Yniv Palti Fredrick T. Barrows James E. Parsons 《Aquaculture International》2012,20(2):213-232
Microarray analysis was conducted using liver samples from two families of rainbow trout that differed in their growth responses
when compared between individuals fed a fishmeal or plant protein-based diet. Differential expression relating to dietary
utilization between the two families found significant changes in expression of 33 expressed sequence tags (ESTs). Eight of
the differentially expressed ESTs had identified mammalian homologs that had been previously researched with identified cellular
interactions and functions. Utilizing pathway analysis software to analyze sequences annotated with known mammalian genes,
we were able to map gene pathways and process interactions. From this information, we were able to infer that the metabolic
changes associated with utilization of plant protein versus fishmeal were associated with differential regulation of genes
related to cell oxidative stress, proliferation, growth and survival. Furthermore, we inferred from the changes we observed
in immune response gene expression that ingestion of this plant-based diet upregulated the expression of genes involved in
immunoregulatory processes. 相似文献
152.
测定四川平武地区5个不同样点的15群东方蜜蜂(Apis cerana)的38个形态特征。同该地区的四川九寨沟、冕宁、西昌、会理以及甘肃岷县、临潭的东方蜜蜂的形态数据进行因素分析、主成分分析、聚类分析以及相关性分析。结果表明:这些地区的东方蜜蜂呈现3个主要类群。该地区东方蜜蜂的个体大小与海拔和纬度相关性显著,喙的颜色、小盾片的颜色和绒毛覆毛长度与海拔相关性显著。 相似文献
153.
Nele Verhulst Ken D. SayreMateo Vargas Jose CrossaJozef Deckers Dirk RaesBram Govaerts 《Field Crops Research》2011,124(3):347-356
Wheat is an important food and income source and estimated demand for wheat in the developing world is projected to increase substantially. The objectives of this study were to gain insight into (i) the effect of tillage-straw system on yield and yield components (number of grains per m2 and thousand kernel weight), (ii) the relation between climatic conditions and yield and yield components, (iii) the explanation of tillage-straw system × year interaction for yield and yield components by climatic co-variables. Wheat grain yield and yield components were measured in a long-term trial established in 1992 under irrigated, arid conditions in northwestern Mexico. Five tillage-straw management systems (conventionally tilled raised beds [CTB] with straw incorporated and permanent raised beds [PB] with straw burned, removed, partly retained or fully retained) were compared for a wheat-maize rotation. Daily climatic data were averaged over six periods corresponding approximately to advancing wheat growth stages. The PB-straw retained and PB-straw removed had the highest yields (average yield of 7.31 and 7.24 t ha−1, respectively) and grains per m2. The PB-straw burned had the lowest yield (average yield of 6.65 t ha−1) and grains per m2, but the highest thousand kernel weight. Maximum temperature was positively correlated to final grain yield during tillering and head differentiation, but was negatively correlated to thousand kernel weight during grain-filling. For the tillage-straw system year interaction, three groups of management systems were distinguished for yield and grains per m2: PB-straw burned, CTB-straw incorporated and PB where straw is not burned. The CTB-straw incorporated had a positive interaction with year in favorable years with high radiation and evapotranspiration. The PB-straw burned was relatively more affected by excess water conditions and showed positive interactions in years with high relative humidity. The PB-straw retained was the most stable in different climatic conditions, indicating that this management system could contribute to maintaining wheat yield in a changing climate scenario. 相似文献
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The Ryukyu Archipelago has a diverse fish fauna, but there have been no comprehensive studies of the larval fish fauna of its coastal habitats. The present study therefore investigated the species composition of larval fish communities on the sandy beach of Sedake and in the estuary of Teima Stream at Oh-ura Bay on Okinawa Island. In total, 12,067 individuals comprising 131 or more species that belong to 114 genera and 48 families were collected at night using a small seine net from January to December 1999. The suborder Gobioidei was the dominant taxon in this collection (86 %) and comprised 53 or more species. Most gobioids were postflexion larvae of amphidromous and estuarine species, at the stage just before they recruited to their adult habitats. Body lengths showed little variance within species. This suggests that they do not spend most of their pelagic larval lives in the estuary and on the sandy beach. These environments appear to be the route by which pelagic larvae move to their adult habitats. However, Rhinogobius and Tridentiger postflexion larvae displayed greater variance in body length and development, suggesting that they stay near the shoreline throughout this larval period. 相似文献
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157.
The effects of l‐DOPA and sulpiride on growth hormone secretion at different injection times in Holstein steers
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The effects of l ‐DOPA, a precursor of dopamine (DA), and sulpiride, a D2‐type DA receptor blocker, on growth hormone (GH) and prolactin (PRL) secretion were investigated in steers. Eight Holstein steers (212.8 ± 7.8 kg body weight) were used. Lighting conditions were 12:12 L:D (lights on: 06.00–18.00 hours). Blood samplings were performed during the daytime (11.00–15.00 hours) and nighttime (23.00–03.00 hours). Intravenous injections of drugs or saline were performed at 12.00 hour for the daytime and 00.00 hour for the nighttime, respectively. Plasma GH and PRL concentrations were determined by radioimmunoassay. l ‐DOPA did not alter the GH secretion when it was injected at 12.00 hour (spontaneous GH level at its peak). On the other hand, l ‐DOPA increased GH secretion at 00.00 hour (GH level at its trough). Injection of sulpiride suppressed GH secretion at 12.00 hour but did not affect GH levels at 00.00 hour. l ‐DOPA inhibited and sulpiride stimulated PRL release during both periods. These results suggest that dopaminergic neurons have stimulatory action on GH secretion and inhibitory action on PRL secretion in cattle. In addition, injection time should be considered to evaluate the exact effects on GH secretion due to its ultradian rhythm of GH secretion in cattle. 相似文献
158.
Shuichi Ito Makiko Hirose Mari Iwahara Azusa Yatsushiro Atsushi Matsumoto Masayuki Tanaka Chinobu Okamoto Ken‐ichi Yayou Tsuyoshi Shimmura 《Animal Science Journal》2017,88(4):691-695
The rhythmic locomotor behavior of flies and mice provides a phenotype for the identification of clock genes, and the underlying molecular mechanism is well studied. However, interestingly, when examining locomotor rhythm in the wild, several key laboratory‐based assumptions on circadian behavior are not supported in natural conditions. The rooster crowing ‘cock‐a‐doodle‐doo’ is a symbol of the break of dawn in many countries. Previously, we used domestic inbred roosters and showed that the timing of roosters' crowing is regulated by the circadian clock under laboratory conditions. However, it is still unknown whether the regulation of crowing by circadian clock is observed under natural conditions. Therefore, here we used red jungle fowls and first confirmed that similar crowing rhythms with domesticated chickens are observed in red jungle fowls under the laboratory conditions. Red jungle fowls show predawn crowing before light onset under 12:12 light : dim light conditions and the free‐running rhythm of crowing under total dim light conditions. We next examined the crowing rhythms under semi‐wild conditions. Although the crowing of red jungle fowls changed seasonally under semi‐wild conditions, predawn crowing was observed before sunrise in all seasons. This evidence suggests that seasonally changed crowing of red jungle fowls is under the control of a circadian clock. 相似文献
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