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1.
Abstract

Annual cycles in hematological parameters, organ weights, and total body fat were measured in two species of mice from a prairie environment. Hematocrit was higher in winter in both Microtus ochrogaster and Peromyscus maniculatus. Plasma protein concentration decreased in winter in both species. Liver, kidneys, and adrenal glands were larger in female P. maniculatus than in males. Greatest liver and kidney size occurred during lactation. Total body lipid was about 5 to 7% of live body weight throughout the year, providing enough energy to survive only about one day of fasting. Adaptive shifts in bodily functions can be expected to coincide with periods of unusual energy expenditure such as lactation and winter. In these mice conserving energy seems to be a more important survival strategy than storing it.  相似文献   

2.
Background & objectivesNatural dietary supplements are progressively getting famous to supplant synthetic substances particularly in chronic morbidities. The aim of this study was to evaluate the anti-obesity potential of almond on the normal, Cafeteria, and Atherogenic diets.Materials and methodsParameters such as change in body weight, body temperature, lipid profile, organ weights, and fat pad weights were assessed. Central Nervous System related studies (Despair Swim test and Elevated Plus maze test) were also performed to comprehend the effect of the diets, and almond on the brain. All of the experimental animals were randomly assigned to one of three diet categoriesregular, cafeteria, or atherogenic, and fed those diets for 40 days. Each diet had the control group, standard drug group and three almond groups (low dose: 50; medium dose: 100 and high dose: 200 mg/kg body weight). Body weight was recorded every alternate day. On 40th day, body temperature was measured. On day 41, lipid parameters, organ weights, fat pad weights and the CNS parameters were evaluated. ANOVA followed by Duncans Multiple Range Test were used for statistical analysis.ResultsTreatment of animals with either a low or high dose of almond as well as a standard herb prevented a rise in body weight significantly (p = 0.01) in all three diet groups. When a regular diet was replaced with a cafeteria and atherogenic diet, the serum levels of triglycerides and LDL increased significantly, while HDL levels decreased significantly. Overall, almond preparation reduced lipid parameters, organ weights, fat-pad weights, and stabilized CNS parameters substantially.Interpretation & conclusionThe almond high dose was the most effective of all the almond preparations. Our study suggests that chronic administration of almond independently reduces the body weight in experimental animals.  相似文献   

3.
Deoxynivalenol (DON) and zearalenone (ZEN) contaminated maize was hydrothermally treated in the presence of sodium metabisulphite (SBS), methylamine and calcium hydroxide (Ca(OH)2) and included into diets for female piglets to evaluate effects on performance, organ weights, development of hyperestrogenism, serum biochemical parameters, stimulation of peripheral blood mononuclear cells and toxin residues in serum. For this purpose, both uncontaminated maize (CON) and Fusarium toxin-contaminated maize (FUS) were included into diets either untreated (?) or treated (+) according to a 2 by 2-factorial design. One-hundred female weaned piglets were assigned to one of the four treatment groups (n = 25) CON?, CON+, FUS? and FUS+ with DON/ZEN concentrations of 0.43/0.03, 0.04/0.0, 3.67/0.32 and 0.36/0.08 mg per kg diet, respectively. After a feeding period of 27 days, 20 piglets (n = 5) were slaughtered. Performance parameters such as feed intake, live weight gain and feed-to-gain ratio remained unaffected by the treatments. Uterus weights were significantly reduced in group FUS+ compared to FUS? (p = 0.028), while visceral organ weights were not influenced. Vulva width in relation to body weight was highest in group FUS? at the end of the trial, while hydrothermal treatment significantly reduced the parameter (p < 0.01). The highest toxin and toxin metabolite concentrations in serum were detected in group FUS?, whereas ingestion of diet FUS+ reduced the concentrations to the level of the control groups. Serum biochemical and haematological parameters were mainly within the given reference ranges and showed no treatment-related alterations. Stimulation of peripheral blood mononuclear cells was not affected. An effective detoxification of maize by hydrothermal treatment in the presence of SBS, methylamine and Ca(OH)2 could be demonstrated by means of serum toxin analyses. No undesired side effects of the treated-feed stuff or the chemicals themselves on the health of piglets were detected.  相似文献   

4.
【目的】研究粘细菌Corallococcus sp. strain EGB及其细胞培养发酵液的毒理安全性,为菌株EGB作为新型生防微生物菌剂的开发和环境施用安全性提供一定的科学基础。【方法】通过Ames试验、小鼠骨髓嗜多染红细胞微核试验和小鼠睾丸染色体畸变试验测定粘细菌EGB菌体及其细胞培养发酵液的遗传毒性;通过经口灌胃的方式测定粘细菌EGB菌体及其细胞培养发酵液对ICR小鼠的急性毒性和28d亚急性毒性。【结果】Ames试验、微核试验和精母细胞染色体畸变试验结果表明,与对照组相比,EGB菌体及其细胞培养发酵液无基因突变能力,对ICR小鼠无明显的遗传毒性。EGB菌体及其细胞培养发酵液对ICR小鼠的急性经口半致死剂量(LD50)>10g/kg BW (body weight);连续灌胃28 d后,处理组ICR小鼠的体重变化、采食饮水、血液生化指标、血常规、主要脏器指数和主要器官病理切片与对照组相比无显著差异(P<0.05)。【结论】粘细菌EGB菌体及其细胞培养发酵液的毒理安全性属于无毒类别,粘细菌的生物安全性使其在工农业领域的植物病害控制和生物转化等方面具有潜在的应用价值。  相似文献   

5.
Summary The electric organ of a fish represents an internal current source, and the largely isopotential nature of the body interior warrants that the current associated with the fish's electric organ discharges (EODs) recruits all electroreceptors on the fish's body surface evenly. Currents associated with the EODs of a neighbor, however, will not penetrate all portions of the fish's body surface equally and will barely affect regions where the neighbor's current flows tangentially to the skin surface. The computational mechanisms of the jamming avoidance response (JAR) in Eigenmannia exploit the uneven effects of a neighbor's EOD current to calculate the correct frequency difference between the two interfering EOD signals even if the amplitude of a neighbor's signal surpasses that of the fish's own signal by orders of magnitude. The particular geometry of the fish's own EOD current thus yields some immunity against the potentially confusing effects of unusually strong interfering EOD currents of neighbors.Abbreviations DF frequency difference - ELL electrosensory lateral line lobe - EOD electric organ discharge - JAR jamming avoidance response  相似文献   

6.
We studied how food abundance and consumption regulates torpor use and internal organ size in the Chilean mouse-opossum Thylamys elegans (Dielphidae), a small nocturnal marsupial, endemic in southern South America. We predicted that exposure to food rations at or above the minimum energy levels necessary for maintenance would not lead to any signs of torpor, while reducing food supply to energy levels below maintenance would lead to marked increases in frequency, duration and depth of torpor bouts. We also analyzed the relationship between food availability and internal organ mass. We predicted a positive relationship between food availability and internal organ size once the effect of body size is removed. Animals were randomly assigned to one of two groups and fed either 70, 100 or 130% of their daily energy requirement (DER). We found a positive and significant correlation between %DER and body temperature, and also between %DER and minimum body temperature. In contrast, for torpor frequency, duration and depth, we found a significant negative correlation with %DER. Finally, we found a significant positive correlation between the %DER and small intestine and ceacum dry mass. We demonstrate that when food availability is limited, T. elegans has the capacity to reduce their maintenance cost by two different mechanisms, that is, increasing the use of torpor and reducing organ mass.  相似文献   

7.
To investigate the influence of selenium on body weights and the immune organ indexes in ducklings administrated with aflatoxin B1 (AFB1), 90 7-day-old ducklings were randomly divided into three groups (groups I–III). Group I was used as a blank control. Group II was administered with AFB1 (0.1 mg/kg body weight). Group III was administered with AFB1 (0.1 mg/kg body weight) plus sodium selenite (1 mg/kg body weight). All treatments were given once daily for 21 days. It showed that the ducklings’ bursa of fabricius, thymus indexes, and body weights in group II significantly decreased when compared with group I (P < 0.01). Furthermore, the spleen indexes significantly decreased (P < 0.01). However, the ducklings’ bursa of fabricius and thymus indexes, body weights in group III ducklings significantly increased when compared with group II (P < 0.01). In addition, the spleen indexes significantly decreased (P < 0.01). These results revealed that AFB1 significantly affect ducklings’ growth and immune organs development. However, selenium significantly ameliorated the negative effects induced by AFB1.  相似文献   

8.
To characterize long-term actions and interactions of growth hormone (GH) and insulin-like growth factor-II (IGF-II) on postnatal body and organ growth, hemizygous phosphoenolpyruvate carboxykinase (PEPCK)-human IGF-II transgenic mice were crossed with hemizygous PEPCK-bovine GH transgenic mice. The latter are characterized by two-fold increased serum levels of IGF-I and exhibit markedly increased body, skeletal and organ growth. Four different genetic groups were obtained: mice harbouring the IGF-II transgene (I), the bGH transgene (B), or both transgenes (IB), and non- transgenic controls (C). These groups of mice have previously been studied for circulating IGF-I levels (Wolf et al., 1995a), whereas the present study deals with body and organ growth. Growth curves (week 3 to 12) were estimated by regression with linear and quadratic components of age on body weight and exhibited significantly (p < 0.001) greater linear coefficients in B and IB than in I and C mice. The linear coefficients of male I and C mice were significantly (p < 0.001) greater than those of their female counterparts, whereas this sex-related difference was absent in the bGH transgenic groups. The weights of internal organs as well as the weights of abdominal fat, skin and carcass were recorded from 3.5- to 8- month-old mice. In addition, organ weight-to-body weight-ratios (relative organ weights) were calculated. Except for the weight of abdominal fat, absolute organ weights were as a rule significantly greater in B and IB than in I and C mice. IGF-II overproduction as a tendency increased the weights of kidneys, adrenal glands, pancreas and uterus both in the absence and presence of the bGH transgene. Analysis of relative organ weights demonstrated significant (p < 0.05) effects of elevated IGF- II on the relative growth of kidneys (males and females) and adrenal glands (females), confirming our previous report on organ growth of PEPCK-IGF-II transgenic mice. In females, IGF-II and GH overproduction were additive in stimulating the growth of spleen and uterus, providing evidence for tissue-specific postnatal growth promoting effects by IGF-II in the presence of elevated IGF-I  相似文献   

9.
Howler monkeys (Alouatta caraya) were studied in northern Argentina and subjected to complete post-mortem examination in connection with field observations of atherosclerosis. In order to estimate age of the animals, data was obtained on gross body dimensions, dental age, and organ weights in 298 animals covering the range of about 1–10 kg. The animals were divided into four size groups, and into male, non-pregnant and pregnant female categories. Statistical parameters were obtained for relative organ weights, organ allometry coefficients, gross body lengths, a body length formula based on the Ponderal Index and dental age. The parameters from howlers were compared with those for rhesus monkeys, chimpanzees, human and general primate organ allometric formulas, and differences due to sex and pregnancy reviewed. It is concluded that the growth pattern in howlers is rather similar to that reported for other primates, which makes it possible to estimate maturity satisfactorily, but that further methods must be developed for post-maturity dating.Publication No. 190 of the Oregon Regional Primate Research Center, Beaverton, Oregon, supported in part by Grants FR 00163 and GM 13605 of the National Institutes of Health.  相似文献   

10.
Summary A knowledge of the precise location of neurosecretory cell bodies is a prerequisite for studying the synthesis and subsequent processing of neurosecretory polypeptides stored in axon terminals comprising the sinus gland of the crustacean eyestalk. Structural data establish that the X organ in the medulla terminalis ganglion (mtXo) of the crayfish eyestalk represents 90–95% of the cell bodies actively synthesizing neurosecretory vesicles stored in the neurohemal sinus gland (Fig. 4). These cell bodies transport rather than accumulate neurosecretory vesicles as judged by light and electron microscopy suggesting that neurohormone precursors, but not subsequently stored products, might be found there. Two-dimensional electrophoresis of sinus gland and mtXo homogenates support this hypothesis. In crayfish, lobster and blue crab, stained two-dimensional gels display a number of sinus gland-specific polypeptides whose high concentrations and low molecular weights are consistent with stored neurosecretory material (Table 1). These neuropeptides are not detected in mtXo homogenates or in non-neurosecretory neural tissue with Coomassie Blue staining. By decreasing the porosity of the second dimension, the two-dimensional gel technique has proven useful in determining the molecular weights of a variety of neurosecretory polypeptides stored in the sinus gland. The crayfish and lobster store several polypeptides of ca. 7,000 Dalton. The blue crab stores two 7,000, two 13,000 and three 20,000 Dalton sinus gland polypeptides detected in stained gels.Following a 4 h incubation in3H-labelled amino acids, predominantly labelled 19,000–21,000 Dalton polypeptides are detected in crayfish mtXo homogenates by 2-D gel autoradiography (Fig. 12). Concomitantly, three labelled polypeptides (4,000–10,000 Dalton) appear in the sinus gland (Fig. 13), suggesting that they are cleaved from 19,000–21,000 Dalton molecules. This study is the first to examine neurosecretory precursors and their putative cleavage products in the Crustacea.Abbreviations mtXo medulla terminalis X organ - NEPHGE non-equilibrium pH gradient electrophoresis - PAF paraldehyde fuchsin - SDS sodium dodecylsulfate  相似文献   

11.
Abstract

In northern Belarus, we have documented a decline in the local stoat Mustela erminea population following the naturalisation of the American mink Mustela vison. The most likely cause is the reduction in the density and distribution of the main prey of stoats, the riparian voles (the water vole Arvicola terrestris and the root vole Microtus oeconomus), due to excessive predation by mink. Since the stoat population has declined, the number of weasels Mustela nivalis in marshlands has increased and their mean body mass has increased, correlated with the higher number and mean weights of rodents available for weasels in marshland compared with forest habitats.  相似文献   

12.
《Plant Ecology & Diversity》2013,6(3-4):495-501
Background: The adaptation, evolution and function of flower colour diversity in response to changing environments are one of the oldest puzzles in plant ecology. It is logical that comparative studies on fitness of flower colour would be the most meaningful if they were conducted on the same genotype.

Aims: We used Gentiana leucomelaena, which produces both white and blue flowers on different tillers of the same individual, as a model species to test adaption and fitness differences of contrasting flowers in contrasting environments.

Methods: We examined seed production by white and blue flowers in response to increased temperatures (28 °C/2 °C vs. 12 °C/2 °C; 12 h light/12 h dark) in a climate chamber study and to watering in the field (+1.5 l m?2 d?1 vs. control with no supplementary irrigation).

Results: For white and blue flowers warming decreased but watering increased seed number. Increased temperature and watering increased the size of seeds from white flowers, but neither warming nor watering significantly changed seed size of blue flowers. Seed size was significantly negatively correlated with seed number in the temperature treatments but positively correlated in watering treatments. The positive correlation was strong in white flowers, but the negative correlation was stronger in blue than in white flowers.

Conclusions: Water availability and low temperature confer an advantage to white flowers, while warming and dry habitats favour blue flowers. These divergent responses may influence total plant fitness and thus help explain the adaptive value and evolution of flower colour diversity.  相似文献   

13.
Using lines of mice having undergone long-term selection for high and low growth, a large-sample (n = ~1,000 F2) experiment was conducted to gain further understanding of the genetic architecture of complex polygenic traits. Composite interval mapping on data from male F2 mice (n = 552) detected 50 QTL on 15 chromosomes impacting weights of various organ and adipose subcomponents of growth, including heart, liver, kidney, spleen, testis, and subcutaneous and epididymal fat depots. Nearly all aggregate growth QTL could be interpreted in terms of the organ and fat subcomponents measured. More than 25% of QTL detected map to MMU2, accentuating the relevance of this chromosome to growth and fatness in the context of this cross. Regions of MMU7, 15, and 17 also emerged as important obesity hot-spots. Average degrees of directional dominance are close to additivity, matching expectations for body composition traits. A strong QTL congruency is evident among heart, liver, kidney, and spleen weights. Liver and testis are organs whose genetic architectures are, respectively, most and least aligned with that for aggregate body weight. In this study, growth and body weight are interpreted in terms of organ subcomponents underlying the macro aggregate traits, and anchored on the corresponding genomic locations. Present address (Joao L. Rocha): Sygen International, 2929 Seventh Street, Berkeley, California 94710, USA.  相似文献   

14.
Abstract

The influence of supplemental food on Rattus exulans populations was investigated by comparing results on a long established live trapping grid (control) with an experimental grid where a constant amount of wheat was provided each month. Parameters such as time of sexual maturity, length of breeding season, growth rates, body weights, and population cycles were compared and all appeared affected by additional food. The large seasonal fluctuations in natural food still exerted an important influence on demographic patterns.  相似文献   

15.
Summary Correlated responses to selection for increased 3–6 week postweaning gain in male mice were estimated for seven internal organs (testes, spleen, liver, kidneys, heart, small intestine (S intest) and stomach) weighed at specific degrees of maturity in body weight (37.5, 50.0, 62.5, 75.0, 87.5 and 100%). Correlated responses in organ weights were generally large, but the magnitude and direction of response depended upon whether 1) comparisons were made at the same age, degree of maturity or body weight and 2) absolute or proportional organ weights were used. The selected line (M16) weighed more and had larger organ weights than controls (ICR) when compared at either the same degree of maturity or the same age, indicating positive genetic correlations between body weight and the respective organ weights. Positive correlated responses were found in spleen weight/body weight at all degrees of maturity and in liver and S intest weights as a proportion of body weight at some degrees of maturity. Testes, kidneys, heart and stomach weights as a proportion of body weight had negative correlated responses, though this was consistent only for kidneys across all degrees of maturity. Correlated responses in organ weights adjusted for body weight by covariance analysis were positive for spleen, S intest and stomach and negative for testes and kidneys. Based on the constrained quadratic model, degree of maturity in organ weight relative to degree of maturity in body weight responded positively for testes, kidneys and S intest and negatively for spleen and liver. Selection for increased growth caused negative correlated responses in allometric growth of testes, kidneys, S intest and stomach.Paper No. 10,545 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, 27695-7601. The use of trade names in this publication does not imply endorsement by the North Carolina Agricultural Research Service of the products named, nor criticism of similar ones not mentioned  相似文献   

16.
Specimens preserved in coal balls collected from the Herrin (No. 6) Coal in Illinois reveal the internal structure of the pteridosperm pollen organ long known as the compression fossil, Potoniea. Cylindrical sporangia are concentrically arranged in a campanulate body and the end of each sporangium projects freely from the distal face of the organ. Pollen is trilete and without a distal germinal aperture. The exine is structureless and has a separable, perine-like layer adorned with orbicules.  相似文献   

17.
Summary

Castration of Helisoma duryi disturbs the balance between growth and reproduction in favour of growth, as is evidenced by the stimulation of body and shell growth and reduction in egg mass production when compared with sham operated controls. Female accessory sex organ wet weight is increased in castrated and virgin snails. Male accessory sex organ wet weight is unaffected and female accessory sex organ wet weight is reduced by dorsal body ablation, suggesting that growth of differentiated female accessory sex organs is stimulated by the endocrine dorsal bodies. Albumen gland synthetic activity is inhibited in the absence of a functioning gonad. This inhibition may be due partly to the accumulation of secretory products within the glands and partly to the inactivation of the endocrine dorsal bodies and neurosecretory caudodorsal cells in the cerebral ganglia. The circulating levels of the vitellogenic protein ferritin are reduced by castration, and increased by injection and implantation of active gonadal tissue into castrates. This may be due to an indirect effect of gonadal factor (s) on the extragonadal synthesis of ferritin.  相似文献   

18.
Abstract

Most natural and synthetic dyes currently used for microbial fluorescent staining are toxic or carcinogenic and are harmful to animals, humans and the environment. A food dye for microbial staining, brilliant blue FCF, was used as an alternative to lactofuchsin and lactophenol blue. Brilliant blue FCF shows pronounced microbial cell fluorescence staining of an array of pathogenic/toxigenic (Fusarium granunearum 3- and 15-acetyldeoxynivalenol chemotypes, and Escherichia coli O157:H7) and beneficial fungi and bacteria (Trichoderma harzianum and Bacillus subtilis). Brilliant blue FCF has no toxic effects on the microbes tested and is inexpensive.  相似文献   

19.
【目的】高亚硝酸盐环境中饲养的凡纳滨对虾(Litopenaeus vannamei),在养殖结束时其生长速率和体重往往差异较大。本研究旨在探讨在高亚硝酸盐环境下饲养的对虾生长速率与肠道菌群结构和功能的相关性。【方法】本研究通过收集高亚硝酸盐条件下快速生长对虾(rapidly growing,RG)、正常生长对虾(normally growing,NG)和缓慢生长对虾(slowly growing,SG)的肠道和海水样品,通过16S rRNA基因测序、线性判别分析[line discriminant analysis(LDA)effect size,LEfSe]等进行分析。【结果】发现SG的细菌群落多样性与RG和NG不同。主坐标分析(principal coordinate analysis,PCoA)分析表明,NG的群落组成与RG比SG更相似。通过LEfSe差异分析发现,RG中火色杆菌科(Flammeovirgaceae)、黄杆菌科(Flavobacteraceae)和浮酶菌科(Planctomycetaceae)的丰度较高,而SG中脱硫弧菌科(Desulfovibrionaceae)、希瓦氏菌科(Shewanellaceae)和弧菌科(Vibrionaceae)的丰度显著增加。【结论】本研究发现,在高亚硝酸盐环境下,肠道微生物群落的氮代谢能力是造成对虾不同生长速度的原因。该研究将为虾的工业化养殖提供指导。  相似文献   

20.
Rhamphichthys rostratus (L.) emits brief pulses (2 ms) repeated very regularly at 50 Hz. The electric organ shows a heterogeneous distribution of the electrocyte tubes and the occurrence of three electrocyte types (caudally innervated, rostrally innervated and marginallycaudally innervated). In the sub-opercular region the electric organ consists of a pair of tubes containing only caudally innervated electrocytes. At the abdominal region the EO consists of three pairs of tubes. Each pair contains one of the described electrocyte types. The number of electrocyte tubes increases toward the tail to reach nine or ten pairs in the most caudal segments. In the intermediate region most tubes contain doubly innervated electrocytes except the ventral pair that contains caudally innervated electrocytes. The caudal 25% contains exclusively caudally innervated electrocytes. The electric organ discharge consists of five wave components (V1 to V5). Electrophysiological data are consistent with the hypothesis that V1 results from the activity of the rostral faces of rostrally innervated electrocytes. V2 results from the activities of rostral faces of marginally-caudally innervated electrocytes while V3 results from the activities of caudal faces of most electrocytes. Curarization experiments demonstrated that V4 and V5 result from action potential invasion and are not directly elicited by neural activity.Abbreviations AEN1 anterior electromotor nerve 1 - AEN2 anterior electromotor nerve 2 - BMB boraxic methylene blue - CIE caudally innervated electrocytes - EMF electromotive force - EO electric organ - EOD electric organ discharge - I current amplitude - MCIE marginally-caudally innervated electrocytes - MT medial tubes - PEN posterior electromotor nerve - R n internal impedance - RIE rostrally innervated electrocytes - Rl load resistor - SAT short abdominal tubes - V voltage amplitude  相似文献   

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