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1.
Low testosterone and estradiol concentrations are predictive for the development of the metabolic syndrome in men and women, respectively. The aim of this study was to investigate the influence of sex hormone deficiency on food intake, body weight, body composition and glucose metabolism in male Göttingen minipigs.Five adult male Göttingen minipigs were studied before castration (pre-cast), 10-18 days (post-cast 1) and 10-11 weeks (post-cast 2) after castration. Parameters of interest were food intake, body weight, body fat percentage and sex hormone concentrations. Furthermore glucose tolerance, glucagon suppression, insulin resistance, beta cell function and disposition index were evaluated by oral and intravenous glucose tolerance tests.Castration led to almost complete disappearance of circulating testosterone and estradiol and secondarily to increased food intake, body weight and body fat percentage. Ten-eighteen days sex hormone deficiency (post-cast 1) did not significantly change any of the investigated metabolic parameters compared to pre-cast levels. Ten weeks after castration (post-cast 2) significant insulin resistance, glucose intolerance and hyperglucagonemia was found, and the beta cell function and the disposition index both were decreased.In conclusion, castration-induced sex hormone deficiency in male Göttingen minipigs results in hyperphagia, obesity and disturbed glucose metabolism, which are some of the features typical for the human metabolic syndrome.  相似文献   
2.
Cellulolytic bacteria became established 12 days after birth in the caecum and colon of conventionally-reared mice fed a diet containing 5 p. 100 crude cellulose (Weende). Their population reached a level between 10(6) and 10(7) bacteria per gram of digestive contents in 25-day-old animals. However, variations between animals were very large; 20 to 50% of the individuals were free of cellulolytic bacteria. A low cellulolytic population was observed in adult mice fed a cellulose-free diet. The amount of cellulose in the diet and its nature (crude or pure cellulose) affected the number of cellulolytic bacteria: the higher the percentage of cellulose in the diet, the higher the number of cellulolytic bacteria, in particular with crude cellulose-containing diet.  相似文献   
3.
2017年12月至2018年3月在江苏盐城湿地珍禽国家级自然保护区,利用粪便显微组织学分析技术结合野外直接观察法对麋鹿(Elaphurus davidianus)冬季食性和食物营养成分进行了分析。野外调查在7条样线上共收集228堆麋鹿粪便,组成14个复合样本进行分析。结果表明,麋鹿冬季食物来源于14科51种植物,其中,芦苇(Phragmites australis,23.09%)和互花米草(Spartina alterniflora,17.58%)为最主要食物,其次为盐地碱蓬(Suaeda salsa,6.50%)、白茅(Imperata cylindrica,5.36%)、獐毛(Aeluropus sinensis,4.90%)、苇状羊茅(Festucas arundinacea,3.83%)、扁秆藨草(Scirpus planiculmis,3.45%)、碱蓬(Suaeda glauca,3.27%)、碱茅(Puccinellia distans,3.12%)、黑麦草(Lolium perenne,2.60%)和茵陈蒿(Artemisia capillaris,2.60%)。麋鹿冬季食物以草本植物为主(96.73%),极少采食木本植物枝叶(3.27%)。被啃食植物中粗蛋白含量基本满足麋鹿越冬营养需求。  相似文献   
4.
Juvenile rainbow trout (Oncorhynchus mykiss) were fed one of three isoenergetic diets varying in protein (35-55%) and lipid content (8-18%), at full satiation levels or half rations for 6 weeks in order to investigate the effects of diet on baseline stress parameters and biotransformation enzyme activity. Growth was greatest in fish fed to satiation on a low protein and high lipid diet. Stress parameters, including plasma lactate, glucose and cortisol concentrations were not significantly affected by dietary treatment or ration. Basal biotransformation enzymes, including glutathione S-transferase (GST) and ethoxyresorufin O-deethylase (EROD) activity, were also unaffected by dietary treatment. Fish exposed to the biotransformation enzyme inducer beta-naphthoflavone did not exhibit an alteration in stress indicators or GST activity; however, EROD activity was increased (87- to 210-fold) in fish receiving all diets and rations. The results of the present study indicate that, unlike mammals, fish may be more recalcitrant to different levels of ingestion of isoenergetic diets varying in protein and lipid concentration with respect to stress responses and the maintenance of basal titers of biotransformation enzymes and their induction.  相似文献   
5.
The effect of diet (made from either animal or plant material) on the partitioning of energy in small (8-16 mm test diameter (td)) and large (29-37 mm td) Psammechinus miliaris was examined. Diet significantly affected ingestion, digestion and growth of both size groups. Assimilation rates of the different types of feed varied and they supported differential development of the body parts. Urchins fed on an algal diet showed poorer absorption efficiency, assimilation, gonadal and somatic growth than individuals fed on an artificial sea urchin diet (mixed plant and animal material) or on the animal based diets. Small urchins fed on a diet of salmon food utilised proteins as the primary energy source rather than carbohydrates or lipids as indicated by low O/N atomic ratios, and salmon diet promoted a higher energetic investment in reproductive development in both size classes. A negative energy balance resulted when large urchins were fed on the algal diet. Energy losses due to ammonia excretion were negligible and the metabolic losses of assimilated energy, measured as oxygen consumption, were between 0.2% and 1.5% with the different diets. A diet made of mussel flesh stimulated ingestion, gave the highest assimilation rates and best overall growth performance. Such detailed information should assist in the design of diets for the cultivation of sea urchins.  相似文献   
6.
Ghrelin expression and secretion seem to be influenced by the fat content of the diet. However, data on the probable adverse effect of high fat diet (HFD) with different dietary fats and saturation level of fatty acids is inconclusive. This study aimed at investigating the effects of HFDs on fasting total and acyl-ghrelin plasma levels, gastric fundus and duodenum ghrelin mRNA expressions. Weaned Wistar rats (n=50) were randomly divided to five groups of HFDs with fish oil (HF-F), olive oil (HF-O), soy oil (HF-S), butter (HF-B) and the controls. After 8weeks, blood samples were collected. While the animals were fasting for 24h, their blood and tissue samples were obtained. Plasma parameters of total and acyl ghrelin and ghrelin mRNA expression level in stomach and duodenum were measured. The HF-B fed group had lower fasting plasma acyl ghrelin level than the control, HF-F and HF-O groups (P<0.05); furthermore, the HF-F group had significantly higher acyl ghrelin level than the HF-S one (P<0.05). After feeding, all the groups, except for the HF-B one, had a significantly lower plasma acyl ghrelin levels (P<0.05), compared with the fasting state. Ghrelin mRNA expression levels in the gastric fundus and duodenum were significantly lower in the HF-B as compared to the control group. Furthermore, the HF-F group had significantly higher mRNA level in the duodenum, in comparison with the HF-B and HF-S groups. As HF-F and HF-O diets had the highest stimulatory effect on fasting ghrelin expression and plasma level, consumption of these dietary oils can play an important role in ghrelin regulation, which might affect feeding behavior and energy intake.  相似文献   
7.
The transition of Australian Aborigines from a diet based on hunting and gathering to an essentially Western diet has been proceeding for almost 200 years, but in some regions was greatly delayed. In 1966/1967 G ould (1980) studied operational aspects of hunting-gathering in desert regions of northwestern Australia and recorded sufficient quantitative and species-specific data to allow definition of the diet over 5 months. By 1966, many Aboriginal people in that region had been displaced from their hunting grounds and were living in camps on cattle stations or in missions. Aboriginal diet on cattle stations in the north-westwas studied in 1951 (Commonwealth Departmentof Health) and shown to consist chiefly of fresh meat, wheaten flour, and sugar with small amounts of vegetables and dairy products. With the granting of citizenship in 1967, most Aborigines were dismissed from cattle stations and were moved first to town camps and later formed remote Aboriginal communities. Studies in the 1980s showed that the self-selected diet in such communities reflected the station diet to a greater extent than the traditional diet. Quantitative presentation of the above three diets, in terms both of foods and of major nutrients, show that many of the dietary inadequacies of the station diet identified in 1951 still persisted in self-selected Aboriginal diets in the 1980s. A comparison of the three diets with a modern recommended dietsupports the nutritional adequacy of the hunter-gatherer diet. Traditional cultural values assigned to food preferences continued to influence food choices in all three diets.  相似文献   
8.
为比较不同饵料、水温对口虾蛄(Oratosquilla oratoria)在越冬期间生长育肥及性腺发育的影响,选用当年池塘养殖口虾蛄[初始体重(21.99±4.86)g,n=600]为研究对象,在养殖设施相同条件下,研究了在自然水温(7.7~13.6℃)和加温(17.1~20.9℃)条件下投喂去壳蛤蜊(Ruditapes philippinarum)和冰鲜杂鱼对口虾蛄的成活率、体长、体宽、体重、性腺指数、肌肉指数及可食率等7项指标的影响。实验共分常温蛤蜊、常温冰鲜杂鱼、加温蛤蜊和加温冰鲜杂鱼4个实验组,实验周期为90 d。结果显示:(1)加温可使口虾蛄成活率显著降低,温度是影响口虾蛄越冬成活的重要因素之一;(2)在整个实验过程中口虾蛄的体长、体宽和体重3项生物学指标均随实验天数的增加呈增长趋势,但各指标不同时间均不存在显著性差异(P 0.05);(3)常温条件比加温条件更有益于口虾蛄性腺指数的增加,其中以常温投喂去壳蛤蜊的效果最好,其性腺指数平均可达14.53%(♀)和7.69%(♂);(4)在整个实验过程中,口虾蛄的肌肉指数随实验进行总体呈上升趋势,除常温蛤蜊与加温蛤蜊实验组间的口虾蛄可食率存在显著性差异(P 0.05)外,其他各实验组两两之间均不存在显著性差异(P0.05);(5)不同饵料和水温的交互影响结果表明,温度是影响口虾蛄性腺指数的重要因素(P 0.01),饵料仅对雌性口虾蛄性腺指数产生显著性影响(P 0.01)。实验结果表明,相对于加温环境,常温环境基本能满足口虾蛄越冬期间的生长和育肥的需求,特别是在10~13℃的水温条件;与冰鲜杂鱼相比,摄食去壳蛤蜊更有利于口虾蛄的性腺发育积累。  相似文献   
9.
The present research work was conducted to assess the impact of nutrient-enriched diet on the physiological activities and subsequently honey yield. Eighteen colonies of Apis mellifera L. were selected from Dera Ismail Khan region, KPK, Pakistan, during the winter and summer seasons, 2019–2020. Five pollen supplement diets were prepared and provided to screen out the palatable one to be fed as pollen alternative nutrition to bee bread. Results of diet consumption regarding mean data for consumption rate displayed that soybean flour enriched artificial diet was maximally consumed (74.34 g) by honey bees per week. Minimum consumption was observed for grinded groundnut enriched diet (64.62 g) which was relatively lesser than the other tested artificial diets. Results of area of worker brood disclosed that soybean flour fortified diet (1489.27 cm2/colony) statistically noteworthy than the other artificial diets whereas control (463.51 cm2/colony) was least effective. Highest bee strength (10.00 bee frames/colony) was noted in the bee colonies fed with soybean flour fortified diet, date paste (8.0 bee frames/colony) was the next effective one, among the tested pollen replacement diets whereas relatively least (5 bee frames/colony) was noticed in case of grinded groundnut. Highest body weight (12.41 g) of neonate bees was noted in case of soybean enriched diet while lowermost (5.31 g) was noted in control bees. Results of wax cell built up and foraging efficiency were also superior in artificial diets than respective control bees. Hence, artificial diets especially soybean-enriched pollen alternative diet can boost up the physiology of honey bee leading to increased honey yield and profit.  相似文献   
10.
We studied the survivorship and reproduction of the cyclopoid Eucyclops serrulatus using four diet types: algae Chlorella vulgaris and Scenedesmus acutus separately and each together with the rotifer Brachionus havanaensis. We used equal biomass (3.9 mg C l−1) of C. vulgaris and S. acutus while B. havanaensis was offered at a density of 0.5 ind. ml−1. Regardless of the food type, the average lifespan of female E.␣serrulatus varied from 30 to 50 days, and those of males from 22 to 27 days. When Chlorella was offered alone as food, the female lifespan was 40% lower than when fed together with B. havanaensis. The number of nauplii per female (gross reproductive rate, GRR) was higher on Scenedesmus alone than on Chlorella alone or Chlorella and Scenedesmus offered with Brachionus. Thus, GRR was not significantly influenced by the presence of rotifer in mixed diet. Net reproductive rate (R o) and the rate of population increase (r) were similar at all the four food types. This implies that the diet-related differences of GRR did not ultimately translate to the differences in R o or r, due to the survivorship patterns of the adult females.  相似文献   
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