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41.
近年来,我国民办高职院校迅猛发展,已经成为高职教育中一支不可忽视的生力军。民办高职院校教学的实训、实习以及校企合作正在摸索阶段。文章以饲料与动物营养专业为例,探讨民办高职院校模块化实训教学体系的构建。  相似文献   
42.
New directions for research identified during the final plenary discussion of the Sixth Symposium on the Biology of Terrestrial Isopods included: locating enzymes buffering pleon fluids during excretion of ammonia and the use of isopods in ecotoxicology including how they adapt to or tolerate high contaminant levels; how they interact with free living and endosymbiotic microbiota and how Wolbacchia avoids the immune response of isopods. New analyses of mating behaviour raised questions concerning mate choice while new microsatellite techniques may help resolve issues of multiple paternity and sperm competition. In relation to their ecology and biogeography new questions included how does the ability to learn the location of high quality food patches in spatially heterogeneous environments and the existence of an Allee effect, influence the population biology of isopods in the field and how do patterns of invasion and colonisation vary between species with different motility and life history strategies?  相似文献   
43.
通过对不同产量类型雷竹林植株及竹笋激素的分析,认为GA3和ABA调控着雷竹鞭侧芽的萌发,也就是影响着竹林的产量,而IAA和CTK对雷竹鞭侧芽的萌发没有明显的调控作用,但影响着竹笋的生长发育;通过对氨基酸含量的分析认为高、中、低雷竹林竹笋的氨基酸含量基本相同,但覆盖雷竹林的春季竹笋氨基酸含量明显下降;通过对竹笋营养成分的分析,得出蛋白质、N、P、K含量从高、中、低产林呈下降趋势,并还认为竹林中适当增施N肥有利于笋产量的提高。  相似文献   
44.

Background

Serotonin (5‐hydroxytryptamine, 5HT) is involved in hypothalamic regulation of energy consumption. Also, the gut microbiome can influence neuronal signaling to the brain through vagal afferent neurons. Therefore, serotonin concentrations in the central nervous system and the composition of the microbiota can be related to obesity.

Objective

To examine adipokine, and, serotonin concentrations, and the gut microbiota in lean dogs and dogs with experimentally induced obesity.

Animals

Fourteen healthy Beagle dogs were used in this study.

Methods

Seven Beagle dogs in the obese group were fed commercial food ad libitum, over a period of 6 months to increase their weight and seven Beagle dogs in lean group were fed a restricted amount of the same diet to maintain optimal body condition over a period of 6 months. Peripheral leptin, adiponectin, 5HT, and cerebrospinal fluid (CSF‐5HT) levels were measured by ELISA. Fecal samples were collected in lean and obese groups 6 months after obesity was induced. Targeted pyrosequencing of the 16S rRNA gene was performed using a Genome Sequencer FLX plus system.

Results

Leptin concentrations were higher in the obese group (1.98 ± 1.00) compared to those of the lean group (1.12 ± 0.07, P = .025). Adiponectin and 5‐hydroytryptamine of cerebrospinal fluid (CSF‐5HT) concentrations were higher in the lean group (27.1 ± 7.28) than in the obese group (14.4 ± 5.40, P = .018). Analysis of the microbiome revealed that the diversity of the microbial community was lower in the obese group. Microbes from the phylum Firmicutes (85%) were predominant group in the gut microbiota of lean dogs. However, bacteria from the phylum Proteobacteria (76%) were the predominant group in the gut microbiota of dogs in the obese group.

Conclusions and Clinical Importance

Decreased 5HT levels in obese group might increase the risk of obesity because of increased appetite. Microflora enriched with gram‐negative might be related with chronic inflammation status in obese dogs.  相似文献   
45.
不同营养液配方与浓度对番茄幼苗生长的影响   总被引:6,自引:0,他引:6  
为了探索适合山西温室番茄无土栽培的营养液配方,研究了不同营养液配方与浓度的营养液对番茄幼苗生长的影响。结果表明,施用荷兰番茄配方的营养液植株生长发育较好,其次是山东农业大学番茄营养液配方和华南农业大学番茄营养液配方,最后是山崎番茄营养液配方。在所有的处理中,标准浓度的营养液对植株株高、茎粗、鲜重、干重和叶面积的增长方面效果最好,其次1/2倍的,最后是1/4倍的,3个浓度的处理间差异极显著。施用荷兰番茄营养液配方标准浓度的营养液与施用其它配方的营养液相比,番茄幼苗的生长期为73 d,比其它配方处理缩短了8 d。  相似文献   
46.
青稞加工利用综述   总被引:4,自引:0,他引:4  
本文综述了青稞的营养价值和药理作用,分析了青稞的加工利用现状,并提出了青稞的开发利用途径,为更好的保护和合理开发利用青稞资源提供依据。  相似文献   
47.
The effects of different diets (natural or pellets) on growth, survival, and moulting interval of juvenile spider crabs, weighing between 0.011–1.56 g and up to 17.6 mm in carapace length, were tested over a period of 90 days. During experiment I, five diets were tested: (1) frozen shrimp—Paleomonetes sp., (2) fresh mussels—Mytilus sp., (3) white fish fillets—Merlucius merlucius, (4) blue fish fillets—Sardina pilchardus, and (5) commercial crustacean pellets. Spider crabs fed fresh mussels grew larger (0.98 ± 0.69 g) and had higher growth rates (4.0 ± 0.7 %BWd−1) compared to the other four diets. The crabs fed shrimp pellet and frozen shrimp grew to intermediate sizes and were smaller than the ones fed fresh mussels, but they were larger than spider crabs fed either blue or white fish fillets (0.46 ± 0.63 and 0.26 ± 0.13 g, respectively) compared to the ones fed white fish fillets (0.12 ± 0.04) and blue fish fillets (0.04 ± 0.02 g). The spider crabs fed blue fish fillets only lasted until day 60 of the experiment, after this day none of the 20 fed this diet were left. During experiment II, two diets were tested: (1) white and blue fish fillets and (2) commercial fish pellet. There were no differences in growth both in weight or carapace length (2.9 ± 1.8 and 2.1 ± 1.5 g in weight, and 18.9 ± 5.0 and 17.7 ± 3.3 mm, respectively) at the end of the experiment. Similarly, there were no differences in growth rates in weight between the two diets (1.2 ± 0.4 and 0.9 ± 0.3 %BWd−1, respectively) or in carapace length (0.4 ± 0.1 and 0.4 ± 0.2 %BWd−1, respectively). Fresh mussel appears to be a very good diet to culture the early stages of this species, while shrimp pellets also deliver acceptable results. On the contrary, frozen shrimp, fish fillets either from blue or white species (much higher lipid content in the blue species), and fish pellets were found to be bad diets for the culture of the early stages of M. brachydactyla.  相似文献   
48.
The effects of artificial diets on growth and body condition of adult cuttlefish, Sepia officinalis were tested in two experiments. Supplemented prepared diets (fish myofibrillar protein concentrate) were fed during a 30-day and a 21-day experiments. Growth, feeding rate and food conversion of group-reared cuttlefish were analyzed. The first of these experiments tested four artificial diets, made with increasing levels of lysine, on adult cuttlefish. According to the chemical analysis, diets 1–3 had limiting concentrations of lysine and other essential amino acids (compared to mantle composition of the cuttlefish), while diet 4 was the only one where almost all essential amino acids were present in concentrations similar or higher than the ones present in cuttlefish mantle. A second experiment was conducted by isolating 16 adult cuttlefish individually, and feeding them the same four artificial diets, in order to obtain individual data. During Experiment 1, only the diet with the best chemical score (diet 4) produced growth (p < 0.05), with a mean instantaneous growth rate (MIGR) of 0.30% wet body weight (BW) d−1. Similarly, individually reared cuttlefish fed diet 4 produced the highest IGR’s (0.26, 0.38 and 0.48% BW d−1) and grew larger (p < 0.01). Comparison of cuttlefish fed the artificial diets vs. thawed shrimp and unfed cuttlefish indicated that cuttlefish fed the artificial diets were in an intermediate state. Growth rates obtained with the artificial diets (<0.4% BW d−1) were considerably lower compared to natural prey, live or frozen, reported by other authors.  相似文献   
49.
Juvenile green abalone Haliotis rufescens were grown under laboratory conditions at 21±1 °C and fed formulated diets consisting of different protein:energy ratios (mg protein/kcal), 62, 74, 85, 100, 108, for 60 days. The level of crude protein ranged from approximately 26% to 44% while the energy content remained constant at about 4.1 kcal g−1. Growth ranged from 3.63 to 12.33 mg day−1. The growth of abalone fed the 100 and 108 diets was significantly greater than that of each of the other diets. Protein efficiency ratio increased as the dietary protein content increased except for the T108 diet (44% crude protein). Abalone apparently consume food to satisfy an energy requirement. Caloric expenditure due to metabolism was estimated for abalone fed diets with protein ratios of 62, 85, 100. Energy loss due to respiration did not vary appreciably among abalone fed the different diets. The proportional distribution of dietary energy into fecal, digestible, growth, and metabolic energy was estimated for abalone fed these diets. Apparent dry matter digestibility was among the lowest for abalone fed the 100 P:E diet, but growth of abalone fed this diet was significantly higher than that of each of the other treatments except the 108 diet. Unexplained energy loss to achieve balance ranged from 7% to 28.5%, some of which is probably due to differential mucus and ammonia production. Results suggest a potential for the reduction of both dietary protein and lipid without causing any adverse effects on the growth response.  相似文献   
50.
小根蒜研究现状及其开发利用   总被引:5,自引:1,他引:5  
介绍了小根蒜的生物学特征、营养价值及其医疗保健功效的研究现状,并对小根蒜的开发利用进行了探讨。  相似文献   
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