Oral lesions, diarrhoea, Pneumocystis carinii pneumonia, tuberculosis and urinary tract infections are some of the opportunistic infections (OIs) which arise when the CD4 cells of the HIV/AIDS patient fall below 200 c...Oral lesions, diarrhoea, Pneumocystis carinii pneumonia, tuberculosis and urinary tract infections are some of the opportunistic infections (OIs) which arise when the CD4 cells of the HIV/AIDS patient fall below 200 cells/mm3. HIV/AIDS infection complications include tissue damage from oral lesions accompanied with pains. Pain is a disagreeable sensory and sensitive experience associated with actual or potential tissue damage. This condition requires immediate treatment with analgesics and antibiotics. However, the inability of rural dwellers to afford readily available drugs is a consequence for using herbs like Bidens pilosa whose local usefulness in the management of oral lesions of HIV/AIDS has not been proven scientifically. Therefore, the objective of this study was to provide the scientific basis in rats for the traditional healers’ use of Bidens pilosa leaves’ extracts in managing pain associated with oral lesions of HIV/AIDS patients in South Western Uganda. Assessment of the analgesic effects of Bidens pilosa was conducted using acetic acid in mice, formalin-induced pain and tail flick methods in rats. Both aqueous and ethanolic extracts of the leaves of Bidens pilosa produced statistically significant dose dependent inhibition of acetic acid induced pain, non dose dependent pain reduction in formalin induced pain, (p < 0.05;student t-test) and non dose dependent tail withdrawal pattern (p < 0.05, Multivariate ANOVA test). Hence, we conclude that extracts of Bidens pilosa have an analgesic basis for their local use in treatment of oral lesions associated pain in HIV/AIDS patients in South-Western Uganda.展开更多
Rodent-borne leptospirosis is by far the most common bacterial zoonosis and it is an important emerging global public health concern in Southeast Asia.Bacterial pathogens associated with rodents,especially those that ...Rodent-borne leptospirosis is by far the most common bacterial zoonosis and it is an important emerging global public health concern in Southeast Asia.Bacterial pathogens associated with rodents,especially those that live in close association with humans have been underreported.To fill this knowledge gap,the present study was undertaken to explore other neglected disease agents that can naturally infect synanthropic rodents.展开更多
Objective:To investigate the prevalence of Calodium hepaticum(C.hepaticum)in rodents and insectivores from Wuhan section of the Yangtze River in China,and to provide evidence for the prevention and treatment of hepati...Objective:To investigate the prevalence of Calodium hepaticum(C.hepaticum)in rodents and insectivores from Wuhan section of the Yangtze River in China,and to provide evidence for the prevention and treatment of hepatic Calodium infection.Methods:Rodents and insectivores were captured from three selected Yangtze River beaches using mousetraps.The three survey sites were divided into six areas according to natural conditions,with 60 mousetraps placed in each area.The liver lesions in the captured rodents were observed by the naked eye and the eggs in the liver tissue were observed by microscopic examination.Results:A total of 1080 mousetraps were placed,and 1075 mousetraps were retrieved,with the retrieve rate as 99.5%.A total of 101 Apodemus agrarius,12 Rattus norvegicus,and 9 Crocidura attenuata were caught.The average density of rodents and insectivores was 10.5%and 0.8%,respectively.DNA of egg nodules from infected rodents showed 98%similarity with that of C.hepaticum 18 S rRNA(LC425008.1).One Rattus norvegicus was infected with C.hepaticum,with an infection rate of 3.23%in the Erqi river beach;the other two beaches did not show the incidence of C.hepaticum.Conclusions:The monitoring of C.hepaticum in the Yangtze River beaches should be strengthened to reduce the risk of human C.hepaticum infection.展开更多
Tick-Borne Rickettsial Diseases (TBRD) are emerging zoonotic diseases, and a problem of human health and veterinary medication. The distribution of these diseases is related to the distribution of vector. The presence...Tick-Borne Rickettsial Diseases (TBRD) are emerging zoonotic diseases, and a problem of human health and veterinary medication. The distribution of these diseases is related to the distribution of vector. The presence of pathogens in the host is a risk indicator of population exposure to these areas. A total of 478 tissues samples from rodents, A. phagocytophilum 18 (3.7%), E. canis 47 (9.8%), Rickettsia rickettsii 18 (3.7%) and E. chaffeensis 19 (3.9%) were detected using species-specific PCR assay. It is the first report in Mexico the presence of rodents infected with A. phagocytophilum and E. chaffeensis. The rodent Peromyscus spp. were the most commonly prevalent host of infection for all the bacteria’s. We have to consider as host of TBRD transmitter and provide a useful contribution to understanding their epidemiology. The health sector should be considered all the fevers of unknown causes in humans and animals in Mexico as infections by these vector-borne rickettsial pathogens.展开更多
<strong>Objectives:</strong> The digestive track of mice and humans has always been an integral part of the pathogenesis of the Trypanosomes but is constantly overlooked. This realization opens up complete...<strong>Objectives:</strong> The digestive track of mice and humans has always been an integral part of the pathogenesis of the Trypanosomes but is constantly overlooked. This realization opens up completely new strategies for the development of trypanosomes vaccines, allowing approaches that parenteral delivery forms would not permit. The target of the study was to compare the haematological changes and immunological responses of trypanosomiasis model systems (mice and rats) inoculated orally and intraperitoneally and to observe the afterward effect of a controlled drug [Isometamidium chloride (ISM)] in the restoration of these initial parameters. <strong>Methods:</strong> To achieve this, a total of 40 rodents (20 rats and 20 mice) were purchased, then grouped into two [sixteen younger (1 - 5 weeks) and older (7 - 15 weeks) groups each]. They were further sub-grouped into five each. Body weights, Parasitaemia and Packed Cell Volume (PCV) were taken before, after inoculation and after treatment with ISM at 4 mg/kg. <strong>Results:</strong> Based on presumptive clinical diagnosis, all rodents inoculated intraperitoneally showed clinical signs of fluctuations in weight, PCV and parasitaemia levels before, after inoculations and after treatment compared to those inoculated orally with a significant difference (P < 0.05) observed. Both young and older rodents also responded differently to the inoculants and to the different methods of inoculation. But more deaths were recorded among the mice when compared to the rats. <strong>Conclusion: </strong>Although these non-transgenic models would not have offered a completely new methods to vaccine development, their differences in response to various methods of inoculations is an indication of an exciting research processes and could offer desired results, particularly where transgenic rodents are employed.展开更多
Dear Editor, Herbal medicines have been used for prevention and treatment of human diseases and promotion of healthy living. These medicines, often self medicated and consumed as concentrated extracts, are not strict...Dear Editor, Herbal medicines have been used for prevention and treatment of human diseases and promotion of healthy living. These medicines, often self medicated and consumed as concentrated extracts, are not strictly regulated. Considering their popular use and increasing safety concerns, thorough evaluations of their efficacy and safety are warranted to protect consumers from potential adverse effects. Toxicity tests (acute, sub- acute and chronic) using animals are widely applied to evaulate adverse effects of a drug and thereby determine its "No Observed Adverse Effect Level" (NOAEL).展开更多
The threat to wildlife population is attributed to various anthropogenic activities. The main objective of this study was to identify the influence of fragment size on the population density of rodents in the study ar...The threat to wildlife population is attributed to various anthropogenic activities. The main objective of this study was to identify the influence of fragment size on the population density of rodents in the study area. Fourteen (14) out of forty (40) fragments existing in the area were randomly sampled. The parameters used for the study were number, size of fragments and the corresponding population distribution of rodents in the study area. Fifty hunters in the area were also interviewed. The fragments were stratified into first, second and third order fragments on the basis of their sizes and randomly selected for the study. Indirect method of wildlife census was carried out through the observation of droppings, trail or tract, burrows, eating habits and noise. Fragment growth rate was 18 to 40 (87.5%) in 7 years. Anthropogenic perturbations in the form of cultivation of permanent cropland, settlement expansion, bush burning, timber exploitation and new settlements in areas previously thinly settled or not accessible to outsiders have resulted in disjointed ecosystems. The population density of rodents correlated with fragment size was highly significant ((P < 0.05) r = 0.9). It was then concluded that fragment size greatly influenced the population and diversity of rodent species. It was recommended that the remaining large fragments in the study area should be protected by law from further fragmentation.展开更多
Many rodent species are currently under conservation threat. However, population monitoring and status assessment are extremely challenging because of small body size, low abundance and elusive behavior of rodents. Fu...Many rodent species are currently under conservation threat. However, population monitoring and status assessment are extremely challenging because of small body size, low abundance and elusive behavior of rodents. Furthermore, invasive methods of capture and tissue collection commonly used to address such studies can induce an unacceptable amount of stress to sensitive species. As a result, noninvasive techniques have become more widely used, but relatively few studies have applied noninvasive techniques to rodents. Here we present two noninvasive alternatives for the collection of DNA from Franklin’s ground squirrels (Poliocitellus franklinii). We compared the quantity, purity and degradation of DNA extracted from plucked hair and fecal pellets to tail snip tissues. We recovered more DNA from tail snips than either plucked hair or fecal pellets. Both hair and fecal pellets recovered DNA with purity ratios similar to tail snips. As expected, DNA recovered from fecal pellets exhibited a high degree of degradation compared to hair and tail tissues. Careful planning of field and laboratory protocols is therefore necessary to compensate for challenges associated with noninvasive tissue types. While there is no tissue that can universally be applied to all research projects, both hair and feces are viable alternatives to traditional invasive procedures and can be applied to threatened and endangered rodent species.展开更多
Toll-like receptors(TLRs),the key sensor molecules in vertebrates,trigger the innate immunity and prime the adaptive immune system.The TLR family of rodents,the largest order of mammals,typically contains 13 TLR genes...Toll-like receptors(TLRs),the key sensor molecules in vertebrates,trigger the innate immunity and prime the adaptive immune system.The TLR family of rodents,the largest order of mammals,typically contains 13 TLR genes.However,a clear picture of the evolution of the rodent TLR family has not yet emerged and the TLR evolutionary patterns are unclear in rodent clades.Here,we analyzed the natural variation and the evolutionary processes acting on the TLR family in rodents at both the interspecific and population levels.Our results showed that rodent TLRs were dominated by purifying selection,but a series of positively selected sites(PSSs)primarily located in the ligand-binding domain was also identified.The numbers of PSSs differed among TLRs,and nonviralsensing TLRs had more PSSs than those in viral-sensing TLRs.Gene-conversion events were found between TLR1 and TLR6 in most rodent species.Population genetic analyses showed that TLR2,TLR8,and TLR12 were under positive selection in Rattus norvegicus and R.tanezumi,whereas positive selection also acted on TLR5 and TLR9 in the former species,as well as TLR1 and TLR7 in the latter species.Moreover,we found that the proportion of polymorphisms with potentially functional change was much lower in viral-sensing TLRs than in nonviral-sensing TLRs in both of these rat species.Our findings revealed the first thorough insight into the evolution of the rodent TLR genetic variability and provided important novel insights into the evolutionary history of TLRs over long and short timescales.展开更多
Fertility control is often heralded as a humane and effective technique for management of overabundant wildlife,including rodents.The intention is to reduce the use of lethal and inhumane methods,increase farm product...Fertility control is often heralded as a humane and effective technique for management of overabundant wildlife,including rodents.The intention is to reduce the use of lethal and inhumane methods,increase farm productivity and food security as well as reduce disease transmission,particularly of zoonoses.We developed a framework to guide researchers and stakeholders planning to assess the effectiveness of a potential contraceptive agent for a particular species.Our guidelines describe the overarching research questions which must be sequentially addressed to ensure adequate data are collected so that a contraceptive can be registered for use in broad-scale rodent management.The framework indicates that studies should be undertaken iteratively and,at times,in parallel,with initial research being conducted on(1)laboratory-based captive assessments of contraceptive effects in individuals;(2)simulation of contraceptive delivery using bait markers and/or surgical sterilization of different proportions of afield-based or enclosure population to determine how population dynamics are affected;(3)development of mathematical models which predict the outcomes of different fertility control scenarios;and(4)implementation of large-scale,replicated trials to validate contraceptive efficacy under various management-scalefield situations.In some circumstances,fertility control may be most effective when integrated with other methods(e.g.some culling).Assessment of non-target effects,direct and indirect,and the environmental fate of the contraceptive must also be determined.Developing fertility control for a species is a resource-intensive commitment but will likely be less costly than the ongoing environmental and economic impacts by rodents and rodenticides in many contexts.展开更多
Rodent pests not only cause severe agricultural loss but also spread zoonotic pathogens to human beings.Antico-agulant rodenticides are widely used to decrease the population densities of rodents but often lead to the...Rodent pests not only cause severe agricultural loss but also spread zoonotic pathogens to human beings.Antico-agulant rodenticides are widely used to decrease the population densities of rodents but often lead to the spillover of ectoparasites becausefleas and ticks may gather on surviving rodents.Therefore,it is necessary to killfleas and ticks before culling rodents to minimize the risk of pathogen transmission.In this study,we used a mixture of ivermectin(an antiparasitic drug)and bromadiolone(an anticoagulant rodenticide)to control both rodent andflea/tick abundances.We found that in a laboratory test,0.01%ivermectin bait was not lethal for greater long-tailed hamsters after 7 days of treatment,while 0.1%ivermectin bait was lethal for approximately 33%of treated rodents.In afield test,bait containing 0.001%,0.005%,0.01%,and 0.05%ivermectin decreased the number offleas per vole of Brandt’s voles to 0.42,0.22,0.12,and 0.2,respectively,compared with 0.77 in the control group,indicating that 0.01%ivermectin bait performed best in removingfleas.In another laboratory test,bait containing a 0.01%ivermectin and 0.005%bromadiolone mixture caused the death of all voles within 6–14 days after the intake of the bait.In thefield test,the bait containing 0.01%ivermectin and 0.005%bromadiolone reduced the average number offleas per vole to 0.35,which was significantly lower than the 0.77 of the control group.Our results indicate that a 0.01%ivermectin and 0.005%bromadiolone mixture could be used to control both rodents andfleas to minimize the spillover risk of disease transmission when using traditional rodenticides.展开更多
One classic system of pulsed resource and animal population is mast seeding and population dynamics of seedeating rodents in forests.However,we still lack an understanding of the global patterns regarding the contribu...One classic system of pulsed resource and animal population is mast seeding and population dynamics of seedeating rodents in forests.However,we still lack an understanding of the global patterns regarding the contributions of seed falls to rodent outbreaks or population dynamics.We analyzed a global dataset of coupled long-term time series of seed abundances and rodent populations from published literature,including 66 and 89 time series(156 rodent-seed pairs from 37 studies)for rodent and seed abundances,respectively.We found only half of the examined rodent populations showed statistically significant coincidence between rodent outbreak and mastseeding years.Over all the coupled time series,seed abundance was found to positively correlate with rodent abundance with a one-year lag,and the relative importance of seed abundance was much lower than that of density dependence in affecting rodent population growth rates.We also found the relative importance of seed abundance decreased,but that of rodent density dependence increased with the latitude of study.For the first time,our work provides a global pattern on the associations between seed falls and rodent population dynamics mostly in midand high-latitude forests,and highlights the necessity of more long-term studies on this subject in more forest ecosystems.展开更多
Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin a...Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin adhesion complexes(IACs) that initiate many signaling functions both at the membrane and deeper within the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins were associated with the evolution of multicellularity, being essential for the association of cells with their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes with a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine wall, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review provides a succinct overview of integrin structure, ligand binding, and signaling followed with a concise overview of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, followed by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, whereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the scientific literature, the illustrations in this manuscript are drafted as Viking imagery for entertainment purposes.展开更多
Some rodents gather and store seeds.How many seeds they gather and how they treat those seeds is largely determined by seed traits such as mass,nutrient content,hardness of the seed coat,presence of secondary compound...Some rodents gather and store seeds.How many seeds they gather and how they treat those seeds is largely determined by seed traits such as mass,nutrient content,hardness of the seed coat,presence of secondary compounds,and germination schedule.Through their consumption and dispersal of seeds,rodents act as agents of natural selection on seed traits,and those traits influence how rodents forage.Many seeds that are scatter-hoarded by rodents are pilfered,or stolen,by other rodents,and seed traits also likely influence pilfering rates and seed fates of pilfered seeds.To clarify coevolutionary relationships between rodents and the plants that they disperse,one needs to understand the role of seed traits in rodent foraging decisions.We compared how the seeds of 4 species of plants that are dispersed by scatter-hoarding animals and that differ in value(singleleaf piñon pine,Pinus monophylla;desert peach,Prunus andersonii;antelope bitterbrush,Purshia tridentata;Utah juniper,Juniperus osteosperma)were pilfered and recached by rodents.One hundred artificial caches of the 4 seed species(25 per species)were prepared,and removal by rodents was monitored.Rodents pilfered high-value seeds more rapidly than the other seeds.Desert peach seeds,which contain toxic secondary compounds,were more frequently recached.Relatively low value seeds like Utah juniper and antelope bitterbrush were pil-fered more slowly and were sometimes left at cache sites,and seeds of the latter species were transported shorter distances to new cache sites.The background density of seeds also appeared to influence the relative value of seeds.展开更多
Local extinction or population decline of large frugivorous vertebrates as primary seed dispersers,caused by hu-man disturbance and habitat change,might lead to dispersal limitation of many large-seeded fruit trees.Ho...Local extinction or population decline of large frugivorous vertebrates as primary seed dispersers,caused by hu-man disturbance and habitat change,might lead to dispersal limitation of many large-seeded fruit trees.However,it is not known whether or not scatter-hoarding rodents as secondary seed dispersers can help maintain natural regeneration(e.g.seed dispersal)of these frugivore-dispersed trees in the face of the functional reduction or loss of primary seed dispersers.In the present study,we investigated how scatter-hoarding rodents affect the fate of tagged seeds of a large-seeded fruit tree(Scleropyrum wallichianum Arnott,1838,Santalaceae)from seed fall to seedling establishment in a heavily defaunated tropical forest in the Xishuangbanna region of Yunnan Province,in south-west China,in 2007 and 2008.Our results show that:(i)rodents removed nearly all S.wallichianum seeds in both years;(ii)a large proportion(2007,75%;2008,67.5%)of the tagged seeds were cached individually in the surface soil or under leaf litters;(iii)dispersal distance of primary caches was further in 2007(19.6±14.6 m)than that in 2008(14.1±11.6 m),and distance increased as rodents recovered and moved seeds from primary caches into subsequent caching sites;and(iv)part of the cached seeds(2007,3.2%;2008,2%)survived to the seedling stage each year.Our study suggests that by taking roles of both primary and secondary seed dispersers,scatter-hoarding rodents can play a significant role in maintaining seedling establishment of S.wallichianum,and are able to at least partly compensate for the loss of large frugivorous vertebrates in seed dispersal.展开更多
Double mutualism,that is,pollination and seed dispersal of the same plant species mediated by the same animal partners,is important but remains elusive in nature.Recently,rodent species were found as key pollinators(i...Double mutualism,that is,pollination and seed dispersal of the same plant species mediated by the same animal partners,is important but remains elusive in nature.Recently,rodent species were found as key pollinators(i.e.explosive openers)for some Mucuna species in(sub)tropical Asia,but no evidence has shown whether and how these rodents could also act as legitimate seed dispersers via scatter-hoarding for those producing large seeds.Here,my aim was to test the hypothesis that scatter-hoarding rodents could act as double mutualists for both pollination and seed dispersal of the same Mucuna species,that is,Mucuna sempervirens(Fabaceae).Based on camera-trapping survey at 2 locations with or without squirrel presence in the Dujiangyan subtropical forests,Southwest China,7 mammals and birds were identified as explosive openers for M.sempervirensflowers,but Leopoldamys edwardsi(rats)and Paguma larvata(civets)were the main pollinators at the squirrel-absent site,while Callosciurus erythraeus(squirrels)were the main pollinators at the squirrel-present site.By tracking the fate of individually-tagged seeds over 5 years at each site,I provide thefirst evidence for seed-eating rodents as legitimate seed dispersers via scatter-hoarding of seeds in this world-wide plant genus,although dispersal services were slightly reduced at squirrel-absent site.More importantly,the dual roles of scatter-hoarding rodents as key pollinators and seed dispersers for the same Mucuna species have shown a clear relationship of double mutualism,and their key services may be essential for population conservation of these Mucuna species in human-disturbed landscapes.展开更多
Dear Editor,Cognitive impairment is a hallmark of neurodegenerative disorders such as Alzheimer’s disease(AD)and Parkinson’s disease.Growing evidence has demonstrated that cognitive impairment is closely associate...Dear Editor,Cognitive impairment is a hallmark of neurodegenerative disorders such as Alzheimer’s disease(AD)and Parkinson’s disease.Growing evidence has demonstrated that cognitive impairment is closely associated with insulin resistance.展开更多
Deforestation and thinning are human activities that can destabilize the forest ecological system and,consequently,impact significantly on habitat and behavior of forest-dwelling animals.This hypothesis was test...Deforestation and thinning are human activities that can destabilize the forest ecological system and,consequently,impact significantly on habitat and behavior of forest-dwelling animals.This hypothesis was tested in Yugong in the Mount Taihangshan area by comparing the tracks of tagged seeds of Armeniaca sibirica.in sites of unthinned and thinned forests.Our results showed that:(i)the diversity of vegetation and rodents drastically reduced in sites with thinned forests,compared to unthinned sites;(ii)the amount of both removed and scatter-hoarded seeds significantly declined in sites with thinned forests,compared with the unthinned sites;(iii)there was no significant difference observed in the distance of seed dispersal between the thinned and unthinned areas;and(iv)the thinning did not show a significant change to the model of cache size.These results suggested that the thinning of forests negatively influenced the species richness and food-hoarding behavior of rodents.In addition,the results indicated that the weakened scattered-hoarding might be disadvantageous to seedling recruitment and forest restoration.展开更多
Rodents,including common voles(Microtus arvalis)and house mice(Mus musculus)cause immense pre-harvest and post-harvest losses.Therefore,developing methods that mitigate these losses while maintaining their role in eco...Rodents,including common voles(Microtus arvalis)and house mice(Mus musculus)cause immense pre-harvest and post-harvest losses.Therefore,developing methods that mitigate these losses while maintaining their role in ecosystems is a priority.Several plant secondary metabolites(PSM)which significantly reduce food intake of both species under laboratory conditions have been identified.However,before these can be used in rodent pest management,they must be tested under more natural conditions where other food sources are available.In this study,the odors of 4 PSMs were evaluated for their repellent effects in experiments conducted in semi-natural enclosures.Soil treated with PSMs or untreated soil(experimental control)was placed in an underground box containing food(rolled oats).We quantified the number of visits to each box and could demonstrate that all 4 PSMs reduced the number of visits to treatment boxes in both rodent species.For common voles the combination of methyl nonyl ketone+black pepper oil was the most repellent PSM.House mice made fewer visits to all PSM boxes;boxes with the anthraquinone were visited least.Furthermore,house mice consumed less food from boxes containing soil treated with all 4 PSMs.Our results suggest that PSMs are repellent in murid and microtine rodents under semi-field conditions.In addition,the future use of PSM odors for repelling both pest species,especially house mice,seems promising.Further investigations with other PSMs,different concentrations as well as alternative application methods are needed to repel common voles from attractive crops.展开更多
Spatial patterns in heterogeneity are generally deemed a central causal factor influencing the physiology and behavior of animals in ecological systems.However,knowledge remains limited about how such patterns influen...Spatial patterns in heterogeneity are generally deemed a central causal factor influencing the physiology and behavior of animals in ecological systems.However,knowledge remains limited about how such patterns influence food discovery by animals.We inferred that spatial heterogeneity plays a key role in animal food discovery and location.To prove this inference,we tested food locating parameters by 2 rodent species,Apodemus agrarius and Lasiopodomys brandtii,in different heterogeneous environments.Our results showed that spatial heterogeneity significantly influenced the food locating time of rodents,with food locating time increasing with increasing spatial heterogeneity.Furthermore,spatial heterogeneity significantly influenced invalid excavations(digging in the wrong place).Finally,spatial heterogeneity significantly influenced the frequency that heterogeneous objects were explored.Supporting our inference,our results indicate that spatial heterogeneity significantly influences the foraging behavior of animals.Consequently,increased spatial heterogeneity will impair the food locating success of rodents.We believe that this work will broaden our understanding of plant–animal interactions.展开更多
文摘Oral lesions, diarrhoea, Pneumocystis carinii pneumonia, tuberculosis and urinary tract infections are some of the opportunistic infections (OIs) which arise when the CD4 cells of the HIV/AIDS patient fall below 200 cells/mm3. HIV/AIDS infection complications include tissue damage from oral lesions accompanied with pains. Pain is a disagreeable sensory and sensitive experience associated with actual or potential tissue damage. This condition requires immediate treatment with analgesics and antibiotics. However, the inability of rural dwellers to afford readily available drugs is a consequence for using herbs like Bidens pilosa whose local usefulness in the management of oral lesions of HIV/AIDS has not been proven scientifically. Therefore, the objective of this study was to provide the scientific basis in rats for the traditional healers’ use of Bidens pilosa leaves’ extracts in managing pain associated with oral lesions of HIV/AIDS patients in South Western Uganda. Assessment of the analgesic effects of Bidens pilosa was conducted using acetic acid in mice, formalin-induced pain and tail flick methods in rats. Both aqueous and ethanolic extracts of the leaves of Bidens pilosa produced statistically significant dose dependent inhibition of acetic acid induced pain, non dose dependent pain reduction in formalin induced pain, (p < 0.05;student t-test) and non dose dependent tail withdrawal pattern (p < 0.05, Multivariate ANOVA test). Hence, we conclude that extracts of Bidens pilosa have an analgesic basis for their local use in treatment of oral lesions associated pain in HIV/AIDS patients in South-Western Uganda.
基金financially supported by the University of Malaya research grant(RP021C-16SUS)Higher Institution Centre of Excellence(HICoE)program(MO002-2019).
文摘Rodent-borne leptospirosis is by far the most common bacterial zoonosis and it is an important emerging global public health concern in Southeast Asia.Bacterial pathogens associated with rodents,especially those that live in close association with humans have been underreported.To fill this knowledge gap,the present study was undertaken to explore other neglected disease agents that can naturally infect synanthropic rodents.
基金financially supported by the Health Bureau of Wuhan(WG17B04)the Health Bureau of Wuhan(WG18Q05).
文摘Objective:To investigate the prevalence of Calodium hepaticum(C.hepaticum)in rodents and insectivores from Wuhan section of the Yangtze River in China,and to provide evidence for the prevention and treatment of hepatic Calodium infection.Methods:Rodents and insectivores were captured from three selected Yangtze River beaches using mousetraps.The three survey sites were divided into six areas according to natural conditions,with 60 mousetraps placed in each area.The liver lesions in the captured rodents were observed by the naked eye and the eggs in the liver tissue were observed by microscopic examination.Results:A total of 1080 mousetraps were placed,and 1075 mousetraps were retrieved,with the retrieve rate as 99.5%.A total of 101 Apodemus agrarius,12 Rattus norvegicus,and 9 Crocidura attenuata were caught.The average density of rodents and insectivores was 10.5%and 0.8%,respectively.DNA of egg nodules from infected rodents showed 98%similarity with that of C.hepaticum 18 S rRNA(LC425008.1).One Rattus norvegicus was infected with C.hepaticum,with an infection rate of 3.23%in the Erqi river beach;the other two beaches did not show the incidence of C.hepaticum.Conclusions:The monitoring of C.hepaticum in the Yangtze River beaches should be strengthened to reduce the risk of human C.hepaticum infection.
文摘Tick-Borne Rickettsial Diseases (TBRD) are emerging zoonotic diseases, and a problem of human health and veterinary medication. The distribution of these diseases is related to the distribution of vector. The presence of pathogens in the host is a risk indicator of population exposure to these areas. A total of 478 tissues samples from rodents, A. phagocytophilum 18 (3.7%), E. canis 47 (9.8%), Rickettsia rickettsii 18 (3.7%) and E. chaffeensis 19 (3.9%) were detected using species-specific PCR assay. It is the first report in Mexico the presence of rodents infected with A. phagocytophilum and E. chaffeensis. The rodent Peromyscus spp. were the most commonly prevalent host of infection for all the bacteria’s. We have to consider as host of TBRD transmitter and provide a useful contribution to understanding their epidemiology. The health sector should be considered all the fevers of unknown causes in humans and animals in Mexico as infections by these vector-borne rickettsial pathogens.
文摘<strong>Objectives:</strong> The digestive track of mice and humans has always been an integral part of the pathogenesis of the Trypanosomes but is constantly overlooked. This realization opens up completely new strategies for the development of trypanosomes vaccines, allowing approaches that parenteral delivery forms would not permit. The target of the study was to compare the haematological changes and immunological responses of trypanosomiasis model systems (mice and rats) inoculated orally and intraperitoneally and to observe the afterward effect of a controlled drug [Isometamidium chloride (ISM)] in the restoration of these initial parameters. <strong>Methods:</strong> To achieve this, a total of 40 rodents (20 rats and 20 mice) were purchased, then grouped into two [sixteen younger (1 - 5 weeks) and older (7 - 15 weeks) groups each]. They were further sub-grouped into five each. Body weights, Parasitaemia and Packed Cell Volume (PCV) were taken before, after inoculation and after treatment with ISM at 4 mg/kg. <strong>Results:</strong> Based on presumptive clinical diagnosis, all rodents inoculated intraperitoneally showed clinical signs of fluctuations in weight, PCV and parasitaemia levels before, after inoculations and after treatment compared to those inoculated orally with a significant difference (P < 0.05) observed. Both young and older rodents also responded differently to the inoculants and to the different methods of inoculation. But more deaths were recorded among the mice when compared to the rats. <strong>Conclusion: </strong>Although these non-transgenic models would not have offered a completely new methods to vaccine development, their differences in response to various methods of inoculations is an indication of an exciting research processes and could offer desired results, particularly where transgenic rodents are employed.
文摘Dear Editor, Herbal medicines have been used for prevention and treatment of human diseases and promotion of healthy living. These medicines, often self medicated and consumed as concentrated extracts, are not strictly regulated. Considering their popular use and increasing safety concerns, thorough evaluations of their efficacy and safety are warranted to protect consumers from potential adverse effects. Toxicity tests (acute, sub- acute and chronic) using animals are widely applied to evaulate adverse effects of a drug and thereby determine its "No Observed Adverse Effect Level" (NOAEL).
文摘The threat to wildlife population is attributed to various anthropogenic activities. The main objective of this study was to identify the influence of fragment size on the population density of rodents in the study area. Fourteen (14) out of forty (40) fragments existing in the area were randomly sampled. The parameters used for the study were number, size of fragments and the corresponding population distribution of rodents in the study area. Fifty hunters in the area were also interviewed. The fragments were stratified into first, second and third order fragments on the basis of their sizes and randomly selected for the study. Indirect method of wildlife census was carried out through the observation of droppings, trail or tract, burrows, eating habits and noise. Fragment growth rate was 18 to 40 (87.5%) in 7 years. Anthropogenic perturbations in the form of cultivation of permanent cropland, settlement expansion, bush burning, timber exploitation and new settlements in areas previously thinly settled or not accessible to outsiders have resulted in disjointed ecosystems. The population density of rodents correlated with fragment size was highly significant ((P < 0.05) r = 0.9). It was then concluded that fragment size greatly influenced the population and diversity of rodent species. It was recommended that the remaining large fragments in the study area should be protected by law from further fragmentation.
文摘Many rodent species are currently under conservation threat. However, population monitoring and status assessment are extremely challenging because of small body size, low abundance and elusive behavior of rodents. Furthermore, invasive methods of capture and tissue collection commonly used to address such studies can induce an unacceptable amount of stress to sensitive species. As a result, noninvasive techniques have become more widely used, but relatively few studies have applied noninvasive techniques to rodents. Here we present two noninvasive alternatives for the collection of DNA from Franklin’s ground squirrels (Poliocitellus franklinii). We compared the quantity, purity and degradation of DNA extracted from plucked hair and fecal pellets to tail snip tissues. We recovered more DNA from tail snips than either plucked hair or fecal pellets. Both hair and fecal pellets recovered DNA with purity ratios similar to tail snips. As expected, DNA recovered from fecal pellets exhibited a high degree of degradation compared to hair and tail tissues. Careful planning of field and laboratory protocols is therefore necessary to compensate for challenges associated with noninvasive tissue types. While there is no tissue that can universally be applied to all research projects, both hair and feces are viable alternatives to traditional invasive procedures and can be applied to threatened and endangered rodent species.
基金supported by the Major Program of National Natural Science Foundation of China(32090023)the National Key R&D Program of China(2022YFC2601602)Hunan Provincial Natural Science Foundation of China(2023JJ41038).
文摘Toll-like receptors(TLRs),the key sensor molecules in vertebrates,trigger the innate immunity and prime the adaptive immune system.The TLR family of rodents,the largest order of mammals,typically contains 13 TLR genes.However,a clear picture of the evolution of the rodent TLR family has not yet emerged and the TLR evolutionary patterns are unclear in rodent clades.Here,we analyzed the natural variation and the evolutionary processes acting on the TLR family in rodents at both the interspecific and population levels.Our results showed that rodent TLRs were dominated by purifying selection,but a series of positively selected sites(PSSs)primarily located in the ligand-binding domain was also identified.The numbers of PSSs differed among TLRs,and nonviralsensing TLRs had more PSSs than those in viral-sensing TLRs.Gene-conversion events were found between TLR1 and TLR6 in most rodent species.Population genetic analyses showed that TLR2,TLR8,and TLR12 were under positive selection in Rattus norvegicus and R.tanezumi,whereas positive selection also acted on TLR5 and TLR9 in the former species,as well as TLR1 and TLR7 in the latter species.Moreover,we found that the proportion of polymorphisms with potentially functional change was much lower in viral-sensing TLRs than in nonviral-sensing TLRs in both of these rat species.Our findings revealed the first thorough insight into the evolution of the rodent TLR genetic variability and provided important novel insights into the evolutionary history of TLRs over long and short timescales.
基金The work was partly funded by the German Federal Ministry of Food and Agriculture due to a parliamen-tary resolution within the federal program“Organic farm-ing and other forms of sustainable agriculture”(grant#2815NA113).
文摘Fertility control is often heralded as a humane and effective technique for management of overabundant wildlife,including rodents.The intention is to reduce the use of lethal and inhumane methods,increase farm productivity and food security as well as reduce disease transmission,particularly of zoonoses.We developed a framework to guide researchers and stakeholders planning to assess the effectiveness of a potential contraceptive agent for a particular species.Our guidelines describe the overarching research questions which must be sequentially addressed to ensure adequate data are collected so that a contraceptive can be registered for use in broad-scale rodent management.The framework indicates that studies should be undertaken iteratively and,at times,in parallel,with initial research being conducted on(1)laboratory-based captive assessments of contraceptive effects in individuals;(2)simulation of contraceptive delivery using bait markers and/or surgical sterilization of different proportions of afield-based or enclosure population to determine how population dynamics are affected;(3)development of mathematical models which predict the outcomes of different fertility control scenarios;and(4)implementation of large-scale,replicated trials to validate contraceptive efficacy under various management-scalefield situations.In some circumstances,fertility control may be most effective when integrated with other methods(e.g.some culling).Assessment of non-target effects,direct and indirect,and the environmental fate of the contraceptive must also be determined.Developing fertility control for a species is a resource-intensive commitment but will likely be less costly than the ongoing environmental and economic impacts by rodents and rodenticides in many contexts.
基金We are grateful to the grant supported by Science and Technology Service Network Initiative of the Chinese Academy of Sciences(KFJ-STS-ZDTP-2021-002).
文摘Rodent pests not only cause severe agricultural loss but also spread zoonotic pathogens to human beings.Antico-agulant rodenticides are widely used to decrease the population densities of rodents but often lead to the spillover of ectoparasites becausefleas and ticks may gather on surviving rodents.Therefore,it is necessary to killfleas and ticks before culling rodents to minimize the risk of pathogen transmission.In this study,we used a mixture of ivermectin(an antiparasitic drug)and bromadiolone(an anticoagulant rodenticide)to control both rodent andflea/tick abundances.We found that in a laboratory test,0.01%ivermectin bait was not lethal for greater long-tailed hamsters after 7 days of treatment,while 0.1%ivermectin bait was lethal for approximately 33%of treated rodents.In afield test,bait containing 0.001%,0.005%,0.01%,and 0.05%ivermectin decreased the number offleas per vole of Brandt’s voles to 0.42,0.22,0.12,and 0.2,respectively,compared with 0.77 in the control group,indicating that 0.01%ivermectin bait performed best in removingfleas.In another laboratory test,bait containing a 0.01%ivermectin and 0.005%bromadiolone mixture caused the death of all voles within 6–14 days after the intake of the bait.In thefield test,the bait containing 0.01%ivermectin and 0.005%bromadiolone reduced the average number offleas per vole to 0.35,which was significantly lower than the 0.77 of the control group.Our results indicate that a 0.01%ivermectin and 0.005%bromadiolone mixture could be used to control both rodents andfleas to minimize the spillover risk of disease transmission when using traditional rodenticides.
基金This work was supported by National Natural Science Foundation of China(32071542,31772471).
文摘One classic system of pulsed resource and animal population is mast seeding and population dynamics of seedeating rodents in forests.However,we still lack an understanding of the global patterns regarding the contributions of seed falls to rodent outbreaks or population dynamics.We analyzed a global dataset of coupled long-term time series of seed abundances and rodent populations from published literature,including 66 and 89 time series(156 rodent-seed pairs from 37 studies)for rodent and seed abundances,respectively.We found only half of the examined rodent populations showed statistically significant coincidence between rodent outbreak and mastseeding years.Over all the coupled time series,seed abundance was found to positively correlate with rodent abundance with a one-year lag,and the relative importance of seed abundance was much lower than that of density dependence in affecting rodent population growth rates.We also found the relative importance of seed abundance decreased,but that of rodent density dependence increased with the latitude of study.For the first time,our work provides a global pattern on the associations between seed falls and rodent population dynamics mostly in midand high-latitude forests,and highlights the necessity of more long-term studies on this subject in more forest ecosystems.
基金supported by USDA-NRICGP 98-35203-6337 to FWB.and RCB,NRSA DHHS/NIH 1-F32-HDO 8501 O1A1 to GAJ,USDA-NRI 2006-35203-17199 to GAJ and Kayla J.BaylessUSDA National Institute of Food and Agriculture Research Initiative Competitive Fellowship Grant no.2012-67011-19892 to James W.Frank and GAJ+1 种基金Agriculture and Food Research Initiative Competitive Grant no.2016-67015-24955 from the USDA National Institute of Food and Agriculture to GAJ and FWBNational Institutes of Health Grant 1R21HD071468-01 to GAJ and KJB。
文摘Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin adhesion complexes(IACs) that initiate many signaling functions both at the membrane and deeper within the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins were associated with the evolution of multicellularity, being essential for the association of cells with their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes with a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine wall, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review provides a succinct overview of integrin structure, ligand binding, and signaling followed with a concise overview of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, followed by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, whereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the scientific literature, the illustrations in this manuscript are drafted as Viking imagery for entertainment purposes.
文摘Some rodents gather and store seeds.How many seeds they gather and how they treat those seeds is largely determined by seed traits such as mass,nutrient content,hardness of the seed coat,presence of secondary compounds,and germination schedule.Through their consumption and dispersal of seeds,rodents act as agents of natural selection on seed traits,and those traits influence how rodents forage.Many seeds that are scatter-hoarded by rodents are pilfered,or stolen,by other rodents,and seed traits also likely influence pilfering rates and seed fates of pilfered seeds.To clarify coevolutionary relationships between rodents and the plants that they disperse,one needs to understand the role of seed traits in rodent foraging decisions.We compared how the seeds of 4 species of plants that are dispersed by scatter-hoarding animals and that differ in value(singleleaf piñon pine,Pinus monophylla;desert peach,Prunus andersonii;antelope bitterbrush,Purshia tridentata;Utah juniper,Juniperus osteosperma)were pilfered and recached by rodents.One hundred artificial caches of the 4 seed species(25 per species)were prepared,and removal by rodents was monitored.Rodents pilfered high-value seeds more rapidly than the other seeds.Desert peach seeds,which contain toxic secondary compounds,were more frequently recached.Relatively low value seeds like Utah juniper and antelope bitterbrush were pil-fered more slowly and were sometimes left at cache sites,and seeds of the latter species were transported shorter distances to new cache sites.The background density of seeds also appeared to influence the relative value of seeds.
基金This work was supported by the National Natural Sci-ence Foundation of China(30930016)the State Basic Research Program(2007CB109102)the open fund from the Key Laboratory of Tropical Forest Ecology,Xishuangbanna Tropical Botanical Garden,Chinese Acad-emy of Sciences.
文摘Local extinction or population decline of large frugivorous vertebrates as primary seed dispersers,caused by hu-man disturbance and habitat change,might lead to dispersal limitation of many large-seeded fruit trees.However,it is not known whether or not scatter-hoarding rodents as secondary seed dispersers can help maintain natural regeneration(e.g.seed dispersal)of these frugivore-dispersed trees in the face of the functional reduction or loss of primary seed dispersers.In the present study,we investigated how scatter-hoarding rodents affect the fate of tagged seeds of a large-seeded fruit tree(Scleropyrum wallichianum Arnott,1838,Santalaceae)from seed fall to seedling establishment in a heavily defaunated tropical forest in the Xishuangbanna region of Yunnan Province,in south-west China,in 2007 and 2008.Our results show that:(i)rodents removed nearly all S.wallichianum seeds in both years;(ii)a large proportion(2007,75%;2008,67.5%)of the tagged seeds were cached individually in the surface soil or under leaf litters;(iii)dispersal distance of primary caches was further in 2007(19.6±14.6 m)than that in 2008(14.1±11.6 m),and distance increased as rodents recovered and moved seeds from primary caches into subsequent caching sites;and(iv)part of the cached seeds(2007,3.2%;2008,2%)survived to the seedling stage each year.Our study suggests that by taking roles of both primary and secondary seed dispersers,scatter-hoarding rodents can play a significant role in maintaining seedling establishment of S.wallichianum,and are able to at least partly compensate for the loss of large frugivorous vertebrates in seed dispersal.
基金supported by the National Natural Science Foundation of China(31971441,31770565)。
文摘Double mutualism,that is,pollination and seed dispersal of the same plant species mediated by the same animal partners,is important but remains elusive in nature.Recently,rodent species were found as key pollinators(i.e.explosive openers)for some Mucuna species in(sub)tropical Asia,but no evidence has shown whether and how these rodents could also act as legitimate seed dispersers via scatter-hoarding for those producing large seeds.Here,my aim was to test the hypothesis that scatter-hoarding rodents could act as double mutualists for both pollination and seed dispersal of the same Mucuna species,that is,Mucuna sempervirens(Fabaceae).Based on camera-trapping survey at 2 locations with or without squirrel presence in the Dujiangyan subtropical forests,Southwest China,7 mammals and birds were identified as explosive openers for M.sempervirensflowers,but Leopoldamys edwardsi(rats)and Paguma larvata(civets)were the main pollinators at the squirrel-absent site,while Callosciurus erythraeus(squirrels)were the main pollinators at the squirrel-present site.By tracking the fate of individually-tagged seeds over 5 years at each site,I provide thefirst evidence for seed-eating rodents as legitimate seed dispersers via scatter-hoarding of seeds in this world-wide plant genus,although dispersal services were slightly reduced at squirrel-absent site.More importantly,the dual roles of scatter-hoarding rodents as key pollinators and seed dispersers for the same Mucuna species have shown a clear relationship of double mutualism,and their key services may be essential for population conservation of these Mucuna species in human-disturbed landscapes.
基金supported by the National Natural Science Foundation of China (81471037 and 81770841)the "Six Kinds of Talents Summit" of Jiangsu Province, China (SWYY-051)+1 种基金Basic Research Program of Education Department of Jiangsu Province, China (14KJA180006)the Program for New Technology of Clinical Diagnosis and Treatment at Nantong (MS22016024)
文摘Dear Editor,Cognitive impairment is a hallmark of neurodegenerative disorders such as Alzheimer’s disease(AD)and Parkinson’s disease.Growing evidence has demonstrated that cognitive impairment is closely associated with insulin resistance.
基金funded by the National Basic Research Program of China(No.2007CB109106)the Key Research Programs in Colleges and Universities of Henan Province(No.16A180039)the Postdoctoral Research Foundation of Zhengzhou University.
文摘Deforestation and thinning are human activities that can destabilize the forest ecological system and,consequently,impact significantly on habitat and behavior of forest-dwelling animals.This hypothesis was tested in Yugong in the Mount Taihangshan area by comparing the tracks of tagged seeds of Armeniaca sibirica.in sites of unthinned and thinned forests.Our results showed that:(i)the diversity of vegetation and rodents drastically reduced in sites with thinned forests,compared to unthinned sites;(ii)the amount of both removed and scatter-hoarded seeds significantly declined in sites with thinned forests,compared with the unthinned sites;(iii)there was no significant difference observed in the distance of seed dispersal between the thinned and unthinned areas;and(iv)the thinning did not show a significant change to the model of cache size.These results suggested that the thinning of forests negatively influenced the species richness and food-hoarding behavior of rodents.In addition,the results indicated that the weakened scattered-hoarding might be disadvantageous to seedling recruitment and forest restoration.
基金the permission of the animal ethics committee of LANUV North Rhine-Westphalia(file number 84-02.04.2012.A151).
文摘Rodents,including common voles(Microtus arvalis)and house mice(Mus musculus)cause immense pre-harvest and post-harvest losses.Therefore,developing methods that mitigate these losses while maintaining their role in ecosystems is a priority.Several plant secondary metabolites(PSM)which significantly reduce food intake of both species under laboratory conditions have been identified.However,before these can be used in rodent pest management,they must be tested under more natural conditions where other food sources are available.In this study,the odors of 4 PSMs were evaluated for their repellent effects in experiments conducted in semi-natural enclosures.Soil treated with PSMs or untreated soil(experimental control)was placed in an underground box containing food(rolled oats).We quantified the number of visits to each box and could demonstrate that all 4 PSMs reduced the number of visits to treatment boxes in both rodent species.For common voles the combination of methyl nonyl ketone+black pepper oil was the most repellent PSM.House mice made fewer visits to all PSM boxes;boxes with the anthraquinone were visited least.Furthermore,house mice consumed less food from boxes containing soil treated with all 4 PSMs.Our results suggest that PSMs are repellent in murid and microtine rodents under semi-field conditions.In addition,the future use of PSM odors for repelling both pest species,especially house mice,seems promising.Further investigations with other PSMs,different concentrations as well as alternative application methods are needed to repel common voles from attractive crops.
基金the National Natural Science Foundation of China(31900336)the National Basic Research Program of China(2007CB109106)+1 种基金the Key Research Programs in Colleges and Universities of Henan Province(16A180039 and 19A180032)the China Postdoctoral Science Foundation(2016M592304).
文摘Spatial patterns in heterogeneity are generally deemed a central causal factor influencing the physiology and behavior of animals in ecological systems.However,knowledge remains limited about how such patterns influence food discovery by animals.We inferred that spatial heterogeneity plays a key role in animal food discovery and location.To prove this inference,we tested food locating parameters by 2 rodent species,Apodemus agrarius and Lasiopodomys brandtii,in different heterogeneous environments.Our results showed that spatial heterogeneity significantly influenced the food locating time of rodents,with food locating time increasing with increasing spatial heterogeneity.Furthermore,spatial heterogeneity significantly influenced invalid excavations(digging in the wrong place).Finally,spatial heterogeneity significantly influenced the frequency that heterogeneous objects were explored.Supporting our inference,our results indicate that spatial heterogeneity significantly influences the foraging behavior of animals.Consequently,increased spatial heterogeneity will impair the food locating success of rodents.We believe that this work will broaden our understanding of plant–animal interactions.