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1.
The increasing frequency of scuticociliatosis in turbot culture has stressed the need of knowledge on the immune responses to these parasites, for further developing of prevention and control strategies. The immune response of turbot to killed parasites, alone (Ag) or in combination with Montanide ISA 763A (MON), was studied in a laboratory-scale experiment. The variations of several innate immune factors and the antibody response were analysed in immunized vs. non-immunized fish at different times after immunization, and also after a challenge with live ciliates. Amongst innate immune factors, serum lysozyme increased progressively in all inoculated groups. Differences in innate immune factors in Ag and Ag-MON fish with respect to controls were mainly evidenced after challenge, especially for serum complement. Serum antibody levels increased in immunized fish after booster and particularly after challenge. In addition, certain protection was obtained for immunized groups compared to controls or to fish receiving MON alone, and the levels of specific antibodies were also the highest in immunized groups. The obtained information could be useful for further design of immunoprophylactic formulations against scuticociliatosis.  相似文献   

2.
Behavior clusters were identified through factor analysis of individual behavior profiles over time and across groups of different composition in a captive vervet monkey (Cercopithecus aethiops sabaeus) colony. The six resulting factors were assessed through examination of (1) the behaviors contributing to each factor, (2) the properties of the factors across groups, and (3) the distribution of individuals along the factor dimensions. Three of the clusters were judged to represent the social roles of Control Male, Control Female, and Subordinate and the other three described the behaviors associated with the developmental stages of yearling (Playful—Protected), juvenile female (Infant focus) and juvenile male (Sex-Play).  相似文献   

3.
Demographic processes and the structure of a population of agile gibbons (Hylobates agilis) were investigated over 6 years in the Gunung Palung Reserve, Indonesia. Estimates of population size, density, and biomass revealed a population whose groups were stable in size and composition. Demographic processes place gibbons at risk, however, to short-term changes in their environment. Patterns of survival, fecundity, mortality, and dispersal combined to produce negative rates of growth. In addition, a top-heavy age-class distribution, with adults forming a large fraction of animals, makes it unlikely that this population could recover rapidly from a decline in numbers. Two behavioral factors, territoriality and monogamy, account for the size and stability of gibbon groups. Monogamy imposes limits on group size, while mating patterns and territoriality decrease the impact of sources of high mortality common in other primate species. These relationships underscore the fundamental importance of behavioral influence on demographic processes and social structure.  相似文献   

4.
Aspects of the predatory behaviour of free ranging Curanx melampygus have been examined in the shallow channel environment of Aldabra Atoll, Indian Ocean. Differences in the frequency of occurrence and number of fish hunting at two adjacent observation areas are described. The numbers of Caranx moving through the area appears to be influenced by tidal factors and possibly the abundance of prey and other environmental factors. The percentage offish hunting increases progressively throughout the day and is most commonly performed by solitary fish or small groups. While approximately equal numbers of Caranx move up or down stream significantly more fish engage in hunting activity when moving down stream which suggests the mechanical advantage of moving with the flow of water has advantages to the hunting fish. Several types of interspecific feeding association are described in which the Caranx is able to scavenge from others or to exploit the hunting methods of other species. More small Caranx form associations than do large Caranx . There is a relationship between the length of a hunting Caranx and the size and/or type of prey that makes an avoidance reaction to it. This relationship between different group sizes and the prey avoidance response is less clearly defined and it is suggested that whether hunting in groups or singly the final interaction is between a single predator and single prey. Ways by which group advantages may occur on grouped prey are described and are considered the result of independent individual action rather than group co-operation. Coastal observations indicate that Caranx use topographic features to shield their approach to areas of high prey density.  相似文献   

5.
Animals optimize the trade-off between the cost of not fleeing and the benefits of staying because the factors that influence flight decisions and the disturbance level of a particular stimulus can vary both spatially and temporally. Different factors (human impact and habitat characteristics) likely to modify anti-predator behaviour in different types of guanaco social groups were analysed. We found that group size was conditioned by high poaching, vehicle traffic, predation risk and vegetation density. Solitary adult males showed shorter alert and flight initiation distances than bachelor and mixed groups. Alert distance was greater during the summer season, and assessment times were shorter when young were present in the groups. In high-predation-risk environments, guanacos detected threats at greater distances and flight initiation distance was longer. Alert distances were shorter on steeper sloped hills and assessment times were shorter in areas with irregular topography than on flat sites. In high traffic areas, flight initiation distance was longer and assessment times were shorter. And in areas with low poaching intensity, assessment times were greater than in those with high poaching levels. Therefore, guanacos may be able to evaluate a true threat. Social group and anti-predator responses were conditioned by habitat characteristics and human impact. We consider that plasticity of responses could be key to the survival of guanacos.  相似文献   

6.
Cross-fostering of infant rhesus macaques between unrelated females has become a routine management strategy at the California Primate Research Center. In order to study the effect of environmental factors on vocal development, we extended this procedure to offspring exchange between two different macaque species living in small social groups. A total of four neonatal Japanese and rhesus monkeys were fostered onto mothers of the other species. Six attempts were required, for an overall success rate of 67%. However, two of the adoptions involved the same foster mother, and both rejections occurred with the same female. The cross-fostered individuals gained weight normally in the first year of life and did not require any hospital treatment. These results indicate that raising nonhuman primate infants with members of a different species can be a viable means of altering species-typical experience without sacrificing essential aspects of maternal care, socialization, and psychological well-being.  相似文献   

7.
The social Diaea are non-territorial, periodically-social spiders that do not weave a snare web, a factor considered to be important in spider sociality. Maternal care and heritable retreats are factors common to most group living animals, including social Diaea; suggesting that they are important factors in the evolution of spider sociality. A 4 year survey, along with field and laboratory experiments revealed that mother spiders provided crucial care in the form of a protective Eucalyptus leaf nest and large prey for their offspring. After the mother's death, the nest was inherited and expanded by the offspring. Larger groups built larger, more protective nests, but expended less individual effort doing so, and so survived better than smaller groups.  相似文献   

8.
[背景] 人体能量稳态失衡表现为体重过轻、超重和肥胖,肠道菌群与人体能量稳态的维持有关,但不同身体质量指数(Body Mass Index,BMI)人群的肠道菌群特征仍需进一步探究。[目的] 基于美国肠道计划公开数据库,解析4类BMI人群肠道菌群的特征,并探究4类BMI人群肠道菌群共存网络特征及差异,为基于肠道菌群来干预肥胖及体重过轻等不健康状态提供新的理论依据。[方法] 从美国肠道计划数据集中筛选具有BMI信息的肠道菌群样本,并根据世界卫生组织规定的BMI划分标准将筛选后的样本分为4类:体重过轻(BMI<18.5 kg/m2),正常体重(18.5 kg/m22),超重(25 kg/m22),肥胖(BMI>30 kg/m2);通过计算和比较肠道菌群的α多样性和β多样性探究4类BMI人群肠道菌群的整体结构特征及差异;通过多元线性回归模型对不同BMI分类与肠道菌群进行相关性分析,并且将地域、年龄、性别因素作为混杂因素加入到模型中进行校正;采用SparCC分别计算4类BMI人群肠道菌群中菌属相关性,并分别构建肠道菌群共存网络。[结果] 经过Wilcoxon秩和检验,发现体重过轻、超重、肥胖人群的肠道菌群α多样性都显著低于正常体重人群;β多样性分析结果表明4类BMI人群肠道菌群的整体结构存在显著差异;4类BMI人群肠道中厚壁菌门(Firmicutes)和拟杆菌门(Bacteroidetes)的相对含量无显著差异;通过MaAsLin分析,并且将地域、年龄、性别因素作为混杂因素加入到模型中进行校正,共得到49个与BMI类型显著相关的物种;4类BMI人群肠道菌群共存网络的拓扑结构具有一定差异,体重过轻和正常体重人群肠道菌群共存网络的复杂度较高,超重和肥胖人群肠道菌群共存网络的复杂度较低。[结论] 4类BMI人群肠道菌群的多样性、整体结构和共存网络间均存在差异。  相似文献   

9.
Hynobius naevius, distributed on western Honshu, Shikoku, and Kyushu Islands of Japan, includes two genetically distinct groups (Groups A and B) that have never been delimited morphologically. Using specimens from the entire species range, we investigated the possibility of distinguishing these groups morphologically. Multivariate analyses of morphometric characters resulted in recognition of two groups that corresponded well to the two genetic groups. One (Group A) was characterized by larger body, compressed tail, shallower vomerine tooth series, bluish- or reddish-purple ground color, and pale-white lateral markings. In contrast, another (Group B) was characterized by smaller body, cylindrical tail, longer vomerine tooth series, reddish-brown ground color, and white lateral markings. Group A was composed of populations from the Chugoku District of Honshu and northern Kyushu, and could not be divided into subgroups, while Group B encompassed populations from the Chubu and Kinki Districts of Honshu, Shikoku and Kyushu, and was subdivided into three local subgroups that are geographically separated by marine straits. Morphometric differentiation in Group A is presumed to have been less affected by genetic factors than by other factors, such as ecological relationships with other, coexisting species. Differentiation in Group B is assumed to have been enhanced not only by genetic but also by climatological factors.  相似文献   

10.
Summary The genetics of specific resistance was studied in F2 populations which segregated for either one or two resistance genes. The resistance factors 1, 11 and 14 which had not previously been characterized genetically segregated as single dominant genes (Dm). Resistance was determined by three linkage groups; R 1/14, 2, 3, and 6 in the first, R 5/8, and 10 in the second and R 4, 7 and 11 in the third. Cultivars of lettuce commonly used in the differential series to detect virulence to R3 and R10, were demonstrated to carry two tightly linked resistance genes. Implications of this linkage arrangement to the manipulation and characterization of these resistance genes are discussed.  相似文献   

11.
The prevalence of mandibular osteomyelitis, which results in a condition called lumpy jaw, and factors associated with its occurrence were investigated in syntopic free-living populations of red deer (Cervus elaphus hispanicus) and fallow deer (Dama dama) in Spain. The study material consisted of 3,586 mandibles from 2,548 red deer and 1,038 fallow deer shot during sport hunting, herd management culls, and programs for population control between 1988 and 1997 (period 1) and 2002 and 2009 (period 2) in eastern Sierra Morena, southern Spain. Disease prevalence ranged from 0.36% to 10.91% among age groups. Older animals were significantly more likely to be affected than younger ones. Red deer stags had higher prevalence than other groups. There was a significantly higher prevalence in period 1, probably associated with differences in climatic and population conditions. High population densities of female red deer contributed significantly to occurrence of disease. Intensive herd management and poor environmental conditions were considered risk factors that increased susceptibility to disease. The study of this affliction could be useful for monitoring general herd welfare and ecologic changes in Mediterranean ecosystems.  相似文献   

12.
目的:通过检测抗Xa因子活性,探讨不稳定型心绞痛患者血小板计数(PLT)对低分子肝素抗凝有效性的影响。方法:入选不稳定型心绞痛患者63例,分为两组,A组(n=24):PLT≥240×109/L,B组(n=39):PLT240×109/L。首先比较两组患者之间一般情况有无差异,而后在两组患者皮下注射那曲肝素前及注射后8 h两个时间点分别进行抗Xa因子活性检测并记录结果,分析两组患者抗Xa因子活性水平并比较活性低于0.5 IU·mL-1患者所占比例。结果:两组患者之间一般情况无显著性差异,抗Xa因子活性治疗前后差异在两组中均有统计学意义,A组治疗后抗Xa因子活性均值低于B组,抗Xa因子0.5 IU·mL-1的患者比率高于B组,组间比较差异显著。结论:在低分子肝素抗凝治疗中,血小板计数≥240×109/L的患者抗Xa因子活性较低,提示不稳定型心绞痛患者在应用低分子肝素后的抗凝力度不足与血小板计数偏高相关。  相似文献   

13.
Sexual segregation seems to be common in bottlenose dolphins, whereby males and females live in different pods that mix mainly for mating. Male dolphins often use aggressive behaviour to mate with females, while females with calves may have different activity and dietary requirements to males and different susceptibility to predation. We investigated the degree of spatial and social sexual segregation in Indo-Pacific bottlenose dolphins (Tursiops aduncus) in a subtropical estuary in Australia. Based on surveys completed over three years, dolphin groups were mostly mixed-sex or female. Mixed-sex groups were found in larger groups in mostly deeper water, whereas, female groups were foraging across all water depths in smaller groups. Aggressive coercive behaviour by males towards females was high, occurring mainly in deeper water, at higher tides, and outside the breeding season. Habitat use by female dolphin groups suggests that shallow tributaries may provide a sanctuary from aggressive males, access to suitable prey items and density for mothers and their calves, or a combination of these factors.  相似文献   

14.
To determine whether immunization with Microcotyle sebastis antigen could induce protection against the parasite's establishment, naive juvenile rockfish were immunized by injection or immersion with whole worm antigen of M. sebastis. The infestation intensities of immunized groups following a challenge (2 wk after boosting) with 5000 M. sebastis eyed-eggs were significantly lower than those of control groups, when determined 7 wk postinfection. The fish in the groups boosted with M. sebastis antigen showed stronger protection than unboosted groups. The control group injected with FCA only showed a significantly smaller number of worms than the control group, which was immersed in PBS containing seawater. The results strongly suggest that both specific and nonspecific immune factors participate in the protection of rockfish against M. sebastis establishment.  相似文献   

15.
16.
When captured by predators, the tadpoles of some species of frogs and toads may release an alarm substance that alters the behaviour of conspecifics. Such ‘alarm response’ behaviour has been proposed as a potential mechanism whereby related conspecifics may ‘warn’ relatives of a predator's presence and thus, improve their inclusive fitness. We examined predator avoidance and alarm response behaviour in tadpoles of the Cascades frog (Rana cascadae) and tested whether such behaviour is influenced by kinship factors. Tadpoles reduced activity when in the presence of a predatory newt (Taricha granulosa). Individuals in sibling groups were more active than both solitary tadpoles and individuals in mixed groups of siblings and nonsiblings. However, we found no evidence of an alarm response in R. cascadae. Behaviour of tadpoles in groups exposed only to predators was not different from that of tadpoles in groups exposed to predators plus crushed conspecifics. Tadpoles in groups exposed to crushed tadpoles were as active as tadpoles in groups exposed to water controls, and some test individuals fed upon the dead tadpoles. Thus, while R. cascadae tadpoles reduce activity in response to newt predators, crushed tadpoles appear to initiate a feeding response rather than an alarm response as has been previously proposed.  相似文献   

17.
The influence of social factors on the modulation of male testosterone levels has been demonstrated among several vertebrate species. In addition to sexual activity, parental care and reproductive competition affect testosterone secretion. We examined variations in testosterone levels among male black howlers (Alouatta pigra) in various social contexts. Fecal samples were collected from nine males living in five different groups in the Mexican state of Campeche. The potential for intragroup and extragroup competition varied among the groups. The number of resident males living in the groups was the only variable that significantly explained variations in testosterone levels. Males living in unimale groups had higher testosterone levels; the highest testosterone levels were recorded for males that had experienced a shift from multimale to unimale group compositions. In this species, the probability of being challenged by extragroup males and evicted from the group during immigration events increases when males live in unimale groups. Therefore, our results suggest that male black howlers respond to competition for group membership by increasing their testosterone levels. In this context, testosterone secretion represents an anticipatory response to reproductive conflicts. Therefore, although males living in unimale groups have exclusive access to females, they face higher physiological costs associated with sustaining high testosterone levels for extended time periods.  相似文献   

18.

[Purpose]

This study was carried out to investigate the effects of different training modes on IL-6 and CRP in patients with type 2 diabetes mellitus (T2DM).

[Methods]

The subjects consisted of 16 middle-aged women with type 2 diabetes mellitus (T2DM), all of whom had no other complications. The 16 subjects were randomly assigned to two experimental groups: the circuit training group (CTG, n = 8) and aerobic training group (ATG, n = 8). Based on measured THR (target heart rate) for maximum oxygen consumption rate, the circuit training group (CTG) exercised at 60% intensity, 60 min/day, 5 sets, 3 days/week for 12 weeks. Based on measured THR (target heart rate) for maximum oxygen consumption rate, the aerobic training group (ATG) exercised at 60% intensity (which was increased gradually in weeks 4, 7, and 10) 60 min/day, 3 days/week for 12 weeks.

[Results]

The results are as follows. Significant decreases in the post training values of weight, % Fat, BMI, IL-6 and CRP (p < .05) were observed in the CTG compared to pre-training. However, there were no differences in the physical characteristic and blood inflammatory factors between the groups (ATG & CTG).

[Conclusion]

In conclusion, the results of this study suggest that circuit training (CT) may be considered as an effective training mode for helping to decrease the blood inflammatory factors (IL-6 and CRP) in patients with type 2 diabetes mellitus (T2DM).  相似文献   

19.
The effects of dietary lipids on haemostasis were investigated in rats fed high fat diets enriched in saturated fatty acids (SAT), oleic acid (OLEIC), MaxEPA® oil (MaxEPA), eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) and results were compared to those for rats fed standard chow (ST). Coagulant activities of factor IIc and factor VII-Xc were reduced by about 70 % in the MaxEPA group and 50 % in the EPA and DHA groups relative to the OLEIC, SAT and ST groups. Liver vitamin K levels were five times lower in the experimental groups than in the ST group, which would indicate an effect of high fat diets on vitamin K metabolism. However, only (n-3) fatty acids prolonged the prothrombin time. These components could act at the post-transiational modification level of vitamin K-dependent plasma clotting factors. The changes in haemostatic factors found in the MaxEPA group were counteracted by vitamin K supplementation.  相似文献   

20.
An investigation of 33 sexual populations of Gonium pectorale has shown sexual isolation not to be as prevalent as previously reported. Only one population was homothallic. Populations from different geographic areas are, in general, sexually compatible. Three groups are discernible based on the degree of intercrossing—the first containing the majority of populations, the second containing only 5 populations, and the third consisting of populations intercrossing with no others. The factors possibly involved in the variable fertility of the populations are discussed. These include the geological history of the collecting areas, migration routes of waterfowl, transport of viable cells by passive means, and cultural conditions (such as pH, temperature, media) used in this investigation.  相似文献   

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