Feeding effects on daily locomotor activity in Carabus auronitens

Daily periodic locomotor activity of Carabus auronitens was recorded in a climate-constant laboratory with the animals exposed to naturally changing photoperiods. Most actograms exhibit directed seasonal variations of duration and phase position of daily activity. Seasonal locomotor activity starts in early spring (following dormancy) on a low daily level, first being confined to a short time span around dusk (and even shorter around dawn). In the course of season, the daily onsets of activity become closely related with sunset and the duration of daily activity is steadily extended with both parts of the bimodal phase fusing to a common, unimodal activity band by late spring. Subsequently, it is further extended into forenoon, until in summer (shortly before aestivation), spontaneous phase inversion turns activity periodicity from nocturnality into diurnality within 1 day. Such seasonal variations are paralleled by changes in the precision of synchronization of the individuals' activity rhythms to the entraining light/dark cycle. No geographical differences were detected. The results support the idea of the circadian clock as a system of two dynamically coupled physiological oscillators that invert their phase relation as soon as the natural dark phase falls short of some minimum-tolerable night length.

PDF HTML阅读 XML下载 导出引用 引用提醒 温度和食物水平对海月水母螅状体无性繁殖的影响 DOI: 10.5846/stxb201404170751 作者: 作者单位: 中国海洋大学,中国海洋大学,中国海洋大学,中国海洋大学,中国海洋大学,中国海洋大学,中国海洋大学 作者简介: 通讯作者: 中图分类号: 基金项目: 国家基础研究重大项目(2011CB403602) The effect of temperature and food supply on the asexual reproduction of moon jelly (Aurelia sp.1) polyps Author: Affiliation: Ocean Univisity of China,Ocean Univisity of China,,,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:水母暴发给近岸人类的生活、渔业资源以及海洋生态系统带来影响。这些近岸海域暴发的水母可以通过有性繁殖和无性繁殖来维持或扩大水母种群数量。在水母生活史中,螅状体的无性繁殖是决定水母体数量的关键阶段,因此对此阶段进行研究。设置了4个温度水平(9、12、15、18 ℃)、3个食物水平(5 个卤虫/螅状体、20 个卤虫/螅状体、40 个卤虫/螅状体),在12个组合条件下研究温度和食物水平对海月水母螅状体无性繁殖能力和方式的影响。研究结果表明,在海月水母螅状体繁殖子体的各种方式中,匍匐茎生殖是主要的繁殖方式,出芽生殖次之,纵向分裂以及足囊出现几率极低。食物对海月水母螅状体产生总子体数影响显著,温度的影响不显著,食物水平越高,海月水母螅状体繁殖子体的能力越强。食物和温度对螅状体发生横裂均有影响,但温度对螅状体横裂的影响更大。温度对螅状体的横裂率影响显著,食物影响不显著。碟状体的释放发生在12、15、18 ℃的条件下,温度是影响海月水母螅状体通过横裂生殖释放碟状体数量的最重要因素。可见在螅状体无性繁殖阶段,温度和食物对繁殖方式的影响各不相同。 Abstract:Jellyfish outbreaks negatively affect humans who live near the coast, and cause harm to fishery resources and marine ecosystems. Jellyfish appearing around the East China Sea maintain or expand their populations by both sexual and asexual reproduction. In the jellyfish's life cycle, asexual reproduction of polyps is a key stage in determining the number of medusa in the following year; therefore, we focused on this life stage in this study. Previous studies have examined the total number of polyps produced by asexual reproduction under varying environmental conditions, but few studies have examined in detail on the number of new polyps formed via each method of asexual reproduction. Our research aimed to describe the methods of asexual polyp reproduction under different temperatures and food availability levels. In our experiment, following other similar studies we used four temperatures (9, 12, 15, and 18℃) and three food amounts (5, 20, and 40 newly-hatched Artemia nauplius per polyp) in a full-factorial experimental design to observe their effects on the asexual reproduction ability and method of moon jellyfish polyp formation. We systematically recorded the number of new polyps, the method of asexual reproduction, strobilation time, rate of strobilation, and the number of ephyrae released. Stolon formation was the most frequent method of asexual polyp reproduction, followed by direct budding. Longitudinal fission and podocyst methods were rarely observed. Food availability had a significant impact on all of the new moon jellyfish polyps, but the influence of temperature was not significant. Reproduction ability was positively correlated with food availability. Both food and temperature treatments influenced strobilation, and temperature had a greater impact on strobilation than food availability. Temperature significantly increased the incidence of strobilation compared with that of other methods of reproduction, but the effect of food supply was not significant. The rate of strobilation was highest in the moderate temperature group (12℃), the 15℃ and 18℃ groups had lower strobilation rates, and the 9℃ group had the lowest strobilation rate. Ephyrae were released at the three higher temperatures (12℃, 15℃, and 18℃). Temperature was the most important factor influencing the progress of the ephyrae released by strobilation, but food supply also had an important influence. The number of ephyrae released per moon jellyfish polyp in the 12℃ group was the greatest at all three food supply levels (5, 20, and 40 newly-hatched Artemia nauplius per polyp), while the 9℃ group did not release ephyrae at any food supply level. The greater the availability of food, the more ephyrae were released by the 12℃, 15℃, and 18℃ groups. At the three highest temperatures, the number of ephyrae released was greatest when 40 newly hatched Artemia nauplius were fed per polyp. Using two-way ANOVA to analyze the influences of temperature and food availability on strobilation and ephyrae release, we conclude that temperature controlled the timing of strobilation, while food amount controlled the number of ephyrae released per polyp. Temperature and food availability have different effects on the asexual methods of jellyfish polyp reproduction. 参考文献 相似文献 引证文献

IntroductionSupervised physical exercise has been shown to benefit patients with heart failure with preserved/mildly reduced ejection fraction (HFpEF/HfmrEF) by improving symptoms and diastolic function. This study aimed to investigate the correlation between unsupervised daily physical activity and changes in daily pulmonary artery pressure (PAP) in patients with stable NYHA class III heart failure (HF) and left ventricular ejection fraction (LVEF) of 45% or higher.MethodsDaily physical activity was monitored over a 3-month period using a Holter-ECG with an accelerometer that calculated an activity-associated, heart rate-derived metabolic equivalent of task (MET) score. PAP was measured using an implanted sensor in 17 patients.ResultsDuring 3 months of PAP monitoring in parallel with Holter ECG in our HF patients (median age 77 [IQR 72–79.5] years, LVEF 55 [49–56] %, mean cardiac index 1.9 ± 0.3), mean, diastolic, and systolic PAP remained unchanged. Patients engaged in unsupervised daily activity with a mean MET score of 5.0 ± 1.2 and a median daily duration of 41 [13–123] minutes. Intensity of daily activity was associated with a higher diastolic PAP on the following day (R2 = 0.017, p = 0.003), particularly in female patients and those with pulmonary hypertension (PH) (female: R2 = 0.044, p = 0.002; PH: R2 = 0.024, p = 0.004). Patients with longer daily activity durations had lower systolic and mean PAP (p = 0.038 and p = 0.048) and a similar diastolic PAP (p = 0.053) after 3 months.ConclusionsTracking changes in daily PAP based on intensity and duration of unsupervised daily activity using implanted sensors and a PocketECG® is feasible. While daily activity duration was not directly linked to diastolic PAP on the first day after daily activity, intensity, especially in female and PH patients, was associated with increased diastolic PAP. In addition, longer daily activity, rather than higher intensity, might be more important for lowering PAP in the long term. Further research in larger trials is warranted to confirm these findings.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00392-024-02564-6.

Validity of cardiac implantable electronic devices in assessing daily physical activity

Seagrass meadows are often important habitats for newly recruited juvenile fishes. Although substantial effort has gone into documenting patterns of association of fishes with attributes of seagrass beds, experimental investigations of why fish use seagrass habitats are rare. We performed two short-term manipulative field experiments to test (1) the effects of food supply on growth and densities of fish, and (2) effects of predation on the density and size distribution of fish recruits, and how this varies among habitat types. Experiments were conducted in Galveston Bay, Texas, and we focused on the common estuarine fish, pinfish Lagodon rhomboides. In the first experiment, replicate artifical seagrass and sand plots were either supplemented with food or left as controls. Recruitment of pinfish was significantly greater to seagrass than sand habitats; however, we detected no effect of food supplementation on the abundance of recruits in either habitat. Pinfish recruits in artifical seagrass grew at a significantly faster rate than those in sand habitats, and fish supplemented with food exhibited a greater growth rate than controls in both sand and artifical grass habitats. In our second experiment, we provided artificial seagrass and sand habitats with and without predator access. Predator access was manipulated with cages, and two-sided cages served as controls. Recruitment was significantly greater to the cage versus cage-control treatment, and this effect did not vary between habitats. In addition, the standard length of pinfish recruits was significantly larger in the predator access than in the predator exclusion treatment, suggesting size-selective predation on smaller settlers or density-dependent growth. Our results indicate that the impact of predation on pinfish recruits is equivalent in both sand and vegetated habitats, and thus differential predation does not explain the higher recruitment of pinfish to vegetated than to nonvegetated habitats. Since predators may disproportionately affect smaller fish, and a limited food resource appears to be more effectively utilized by fish in vegetated than in unvegetated habitats, we hypothesize that pinfish recruits may select vegetated habitats because high growth rates allow them to achieve a size that is relatively safe from predation more quickly.

For insect parasitoids, knowledge of their flight capability is essential for a general understanding of the relationship with their hosts. For instance, flight capacity might partly determine their efficacy as biological control agents. Ibalia leucospoides Hochenwarch (Hymenoptera: Ibaliidae) is a solitary, pro-ovigenic parasitoid of the woodwasp, Sirex noctilio Boidin (Hymenoptera, Siricidae), an economically important pest of softwood forestation. This study explores the flight capacities of I. leucospoides females and assesses the effects of a sugar-rich food supply and crowding on female flight performance, by using computer-linked flight mills. The present study shows: (1) a high variability in flight potential of I. leucospoides females, (2) no effects of food supply and grouping on wasp flight (flight distance and speed), (3) a significant effect of body size and wing loading on flight performance and, (4) a significant body mass loss during the flight dependent on the total distance flown. The lack of effect of food on a highly energy-demanding activity as flight may be related to the life-history traits and nutritional strategies of this parasitoid. The relevance of these observations for the use of I. leucospoides as a biological control agent is discussed.

In avian species, circannual rhythms, in a number of biological variables, including locomotor activity, have been studied under both laboratory and natural environmental conditions. However, information on circannual rhythm in daily activity duration of Indian cliff swallow (Hirundo fluvicola) is not available. It is a communal mud nesting, non-migratory species and inhabits low under arch bridges. Although it figures in the IUCN Red List under the least concerned category, it is important to study its behavioral ecology that may be of utmost importance from conservation stand point. In the present investigation, we examined the circannual rhythm in daily activity duration in this species at a communal roosting site under Kharoon river bridge on the Raipur–Bhilai highway (21°15′07.54′′N; 81°32′30.65′′E), Raipur, India, for eight consecutive days, every month from August 2009 to October 2011. On each study day, observations were made in two sessions, morning and evening. We monitored and recorded emergence time of the first bird from the nest in the morning and entry time of the last bird to the nest in the evening. We also recorded the ambient temperature and humidity of the study site simultaneously. Average daily activity duration (the time difference between the first bird’s emergence time and the last bird’s entry time from/to the nest, respectively) was computed for each month. A significant circannual rhythm in activity duration was validated. The peak of activity rhythm occurred on 22nd June with a spread between 19th June and 25th June. The activity duration was the shortest in winter and the longest in summer. The daily activity duration was positively correlated to the day length, sunset time, and morning and evening temperatures; whereas negatively correlated with the sunrise time, and morning and evening humidity. The multiple linear regression models suggest that day length alone explains 96% of the total variance in activity duration, whereas only 0.5% variance was attributable to evening temperature. We conclude that the day length is the strongest predictor of circannual variation in daily activity duration of the colony of Indian cliff swallow; whereas the evening temperature has very little effect. Further, we recommend that comparable studies under natural conditions might be very helpful to explore the effect of environmental cues on other intriguing behavioral decisions made by this and other avian species.

Sedentary behavior is thought to contribute to worsening heart failure syndromes. Here, we examined whether the shelter-in-place order during the coronavirus disease 2019 (COVID-19) pandemic changed daily activity duration, which was monitored by an implantable cardiac device-based multisensor index and alert algorithm called HeartLogic. We performed a retrospective review of the HeartLogic data from patients with heart failure managed at our clinic and compared the individual daily activity duration 90 days prior to vs. after implementation of the shelter-in-place order. The activity data were prepared by Boston Scientific. Demographic data were extracted from our electronic medical record. In total, 29 patients were included in the analysis. Among them, 14 patients did not have any significant changes in daily activity duration compared to their baseline before the shelter-in-place order (108.62 ± 45 min vs. 107.71 ± 48.6 min, P = 0.723). Among the rest 15 patients with significant changes, seven patients had a significant reduction in activity duration; meanwhile, eight patients had a significant increase in activity duration. Overall, the mean daily activity duration 90 days before and after the shelter-in-place order are 98.21 ± 60.83 min, and 100.03 ± 68.18 min (P = 0.753). No significant changes in terms of activity duration were observed in our patients during the COVID-19 pandemic.

Temperature is one of the most critical environmental factors that influence various biological processes. Species distributed in different temperature regions are considered to have different optimal temperatures for daily life activities. However, how organisms have acquired various features to cope with particular temperature environments remains to be elucidated. In this study, we have systematically analyzed the temperature preference behavior and effects of temperatures on daily locomotor activity and sleep using 11 Drosophila species. We also investigated the function of antennae in the temperature preference behavior of these species. We found that, (1) an optimal temperature for daily locomotor activity and sleep of each species approximately matches with temperatures it frequently encounters in its habitat, (2) effects of temperature on locomotor activity and sleep are diverse among species, but each species maintains its daily activity and sleep pattern even at different temperatures, and (3) each species has a unique temperature preference behavior, and the contribution of antennae to this behavior is diverse among species. These results suggest that Drosophila species inhabiting different climatic environments have acquired species-specific temperature response systems according to their life strategies. This study provides fundamental information for understanding the mechanisms underlying their temperature adaptation and lifestyle diversification.

Melatonin reduces locomotor activity and circulating cortisol in goldfish

Sumatran elephant (Elephas maximus sumatranus) is a social animal living in groups. A group of elephant is called herd consists of male, female, allomother and calf. Non-parenting females are called allomother with the role of maintaining calves from other females. In daily activity, allomother may also display a typical infant handling which is valuable for studying interaction between them. This study will describe the daily activity of elephant allomother in Tangkahan Conservation Response Unit (CRU) Area, Langkat, North Sumatera. Methodology used was focal animal sampling with continuous sampling of data record. Object in this study were two allomothers, namely Ardana and Sari with three calves, namely Christopher, Albertina and Eropa. Daily activities of allomothers were recorded as Defecating (DF), Urinating (UR), Mudding (MU), Resting (RE), Mating (MT), Salting (ST), Feeding (FE), Parenting (PR), Drinking (DR) and Walking (WK). We recorded 19,569 sample points from allomother daily activities with Ardana having 10,838 points and Sari having 8,821 points. The longest duration of activity recorded were: Parenting (PR) with 5,807.13 min, Walking (WK) with 5,695.50 min and Feeding (FE) with 3,842.71 min. The shortest duration recorded was Mating (MT) with only 18.96 min while remaining activities lasting between 346.25 to 614.63 min. Duration of daily activities is directly proportional to the percentage of frequency performed by allomothers.

Seasonality in circadian locomotor activity and serum testosterone level in the subtropical tree sparrow (Passer montanus)

This study concerns the relation between use and fibre type composition among limb muscles. The histochemical properties were investigated for ankle muscles from cats that had previously been studied in 24 hr electromyographic (EMG) recordings of daily spontaneous activity. We then reported average daily "duty times" (i.e. the percentage of total sampling time filled with EMG activity) of 1.9% for extensor digitorum longus (EDL), 2.1 and 4.0% for anterior and posterior sites of tibialis anterior (TA), 6.6 and 9.5% for anterior and posterior sites of peroneus longus (PL), and 13.9% for soleus (SOL). In the present experiments, muscles from which these data had been obtained were sectioned in a cryostat and stained for myofibrillar ATPase. Fibres were classified as type I (presumably slow) or II (presumably fast), the latter fibres being further categorized as IIA, IIB and a minor portion of transitional IIAB fibres. As expected, SOL was 100% type I. Among the muscles of mixed fibre-type composition ("mixed muscles"), a statistically significant difference in the mean percentages of type I fibres was found between TA or EDL (2.9-6.0%) vs. PL (11.8-14.6%). For TA the percentage of type I fibres was higher in posterior (deep) than in anterior (superficial) sampling regions; for PL no clear antero-posterior difference was found. A significant correlation was obtained between the percentage of type I fibres and the total duration of daily activity recorded from corresponding mixed muscle sites (5 different recording sites in 4 cats, totally 15 cases of successfully combined physiological and histochemical measurements, r = 0.76, P < 0.001). Similarly, within TA the total duration of daily activity was higher for sites with high (posteriorly) than for those with low (anteriorly) percentages of type I fibres. a "coarse-grain" relationship was found between fibre type composition and the duration of daily activity among mixed muscles. Possible mechanisms underlying this relationship are discussed.

The Breeding of the Kestrel, Falco Tinnunculus L., in the Reclaimed Area Oostelijk Flevoland

The aim of this study was to evaluate the daily total locomotor activity in captive Chrysocyon brachyurus. Three maned wolves were housed individually under natural light–dark cycle and environmental conditions. In each animal, locomotor activity was monitoored for 30 days by means of an activity data logger (Actiwatch Cambridge©Neurotechnology, Cambridge, UK), applied on a neck collar. Locomotor activity was evaluated by visual inspection of actograms. The average amount of activity during light and dark phases and Cosine 20 Peak were calculated using Actiwatc Activity Analysis 5.06. Subject A was more active during the light phase, and subjects B and C were more active during the dark phase. The single cosinor method applied on the amount of activity recorded every hour showed a daily rhythm of locomotor activity only in subject B (2 years old). Acrophase was observed between 03:20 and 07:30, and robustness had a value between 37.00% and 63.40%. Only one subject due to their early withdrawal from its natural habitat, developed a manifest anthropic dependence, with a marked adaptation to the habitat of captivity presenting an anthropophilic behavior. This study would help to define more appropriate management and conservation strategies for this emblematic mammal of South America.