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1.
One Health ; 19: 100894, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39345729

RESUMEN

During the coronavirus disease 2019 (COVID-19) pandemic, hospitals and households have used personal protective equipment (PPE), such as masks and gloves. Some of these potentially infectious materials were discarded with other household wastes in garbage dumping sites. Thus, this study aimed to detect the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in contaminated wastes, environments, and mammals scavenging around these sites. From September to October 2022, we visited three garbage dumping sites located in Bangkok, Nakhon Pathom, and Nonthaburi provinces of Thailand. Oral, nasal, rectal swabs, and blood samples were collected from small mammals, stray dogs, and cats. Masks, gloves, soil, and water samples from the sites were additionally collected. Of the 582 samples collected from 238 animals, none tested positive for SARS-CoV-2 in the virus isolation, real-time reverse-transcription polymerase chain reaction, and neutralizing antibody detection. However, one sample (1.18 %; 1/85) from a rat (Rattus spp.) captured in Nonthaburi was serologically positive in the indirect enzyme-linked immunosorbent assay. The surveillance of coronaviruses in rats is strongly encouraged because rats may harbor different zoonotic pathogens, including unknown potentially zoonotic coronaviruses. Moreover, two face mask samples (4.65 %; 2/43) collected from the dumping site in Nakhon Pathom tested positive for SARS-CoV-2 by real-time RT-PCR. To reduce environmental contamination, detecting the SARS-CoV-2 viral genome in contaminated face masks highlights the critical need for proper waste management in households and communities in Thailand. Thus, to minimize exposure and prevent onward transmission, waste management personnel, including garbage dump staff and waste pickers, should be equipped with appropriate PPE and receive regular training on safe handling and disposal.

2.
Ecol Evol ; 14(9): e70344, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39315302

RESUMEN

Most mammals rely on vocal communication to increase survival and reproductive success. While the functions of audible vocalizations have been well-studied across mammal species, ultrasonic vocalizations in small mammals outside of bats are less understood. North American flying squirrel species (Glaucomys spp.), including the newly described Humboldt's flying squirrel (Glaucomys oregonensis), produce numerous call-types that extend into the ultrasonic range. To investigate the potential function of ultrasonic call-types in the Humboldt's flying squirrels, we used ultrasonic recorders to record squirrels in the wild across multiple seasons to determine if there are temporal and seasonal patterns in nightly vocal activity and rates of different call-types. We recorded Humboldt's flying squirrels in two geographic locations - Humboldt and San Bernardino counties-in California from 2018 to 2022 in the summer and winter across multiple study areas. We found that although seasonal weather conditions differ between locations, flying squirrels in Humboldt and San Bernardino had similar vocal activity patterns across nightly active periods between locations and between summer and winter. Nightly activity patterns of when the three main chirp-like call-types (arc chirps, tonal chirps, upsweeps) were given varied between seasons in both geographic locations, and these call-types were given at greater rates in the summer in San Bernardino, but rates did not vary by season in Humboldt. Trills, the most structurally complex of the four main call-types, were produced more in the summer than in winter, and also differed in their nightly activity patterns, in both geographic locations. Flying squirrels may use certain call-types earlier or later in the nightly active period due to their potentially varying functions, and may produce more trills in the summer coinciding with the breeding season. Further understanding of the function of different call-types can provide insight into social, foraging, and antipredator behavior of this nocturnal and elusive species.

3.
Animals (Basel) ; 14(17)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39272347

RESUMEN

While most studies focused on the impact of intensive agriculture on the barn owl's diet, little is known about the effect of cropland abandonment. We compared the taxon composition/evenness and feeding guild structure of small mammal prey identified in pellets collected before (2004) and after (2012) the abandonment of 9% of cultivated fields within a cultural landscape. Data on prey abundance per pellet were analysed through non-metric multidimensional scaling and permutational, paired tests. Prey taxon evenness in 2012 was significantly lower than in 2004. That induced a shift in prey taxon composition as indicated by the significantly lower dietary similarity compared with the random expectation. The increasing and declining abundance of Murinae and Crocidurinae, respectively, had the largest contribution to the differentiation of the diet spectrum. Insectivorous prey was significantly more abundant in 2004 compared to 2012, while the opposite was true for omnivorous prey. Our results suggest that even a small fraction of abandoned crops in the landscape might induce a detectable shift in the barn owl's food niche. The dietary effects are similar to those observed after agricultural intensification, that is, an increase in the abundance of generalists to the detriment of specialist mammal prey.

4.
Pest Manag Sci ; 80(11): 5597-5607, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39248040

RESUMEN

Globally, human-wildlife conflicts continue to increase, owing to human population growth and expansion. Many of these conflicts concern the impacts of invasive non-native species. In the UK, the invasive, non-native grey squirrel Sciurus carolinensis negatively affects tree health and has caused the decline of the native red squirrel Sciurus vulgaris. Oral contraceptives are being developed to manage the impacts of the grey squirrel. To be effective, contraceptives will need to be deployed at a landscape scale, and will require a delivery system that is practical and economically viable. Understanding grey squirrel feeding behaviour is important so that delivery methods can be designed so that a sufficient number of target individuals receive an effective contraceptive dose at a time of year that will ensure their infertility throughout peak times of breeding. The main aims of this study were to assess how sex, season, squirrel density and bait point density influenced; (1) the probability of a squirrel visiting a feeder and (2) the amount of bait consumed from feeders. Field trials were conducted on six woodland populations of squirrels in three seasons, with four days of bait deployment via purpose-designed squirrel-specific bait hoppers with integrated PIT-tag readers. It was possible to deliver multiple doses on most days to most male and female grey squirrels, with bait deployment more likely to be effective in spring, immediately before the second annual peak in squirrel breeding, followed by winter, immediately before the first peak in breeding. The results from this study could be used to design methods for delivering oral contraceptive baits to grey squirrels in the future and the methods used could be applied to other small mammal species and other bait delivery systems. © 2024 Crown copyright and The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. This article is published with the permission of the Controller of HMSO and the King's Printer for Scotland.


Asunto(s)
Sciuridae , Estaciones del Año , Animales , Sciuridae/fisiología , Femenino , Masculino , Anticonceptivos Orales/administración & dosificación , Conducta Alimentaria , Densidad de Población
5.
Front Vet Sci ; 11: 1378346, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39183750

RESUMEN

Introduction: The increasing prevalence of antimicrobial resistance (AMR) and multidrug resistance (MDR) in microorganisms poses a significant concern in both human and veterinary medicine. Non-traditional companion animals (NTCAs), particularly popular amongst households with children, play a crucial role in AMR epidemiology due to their rising population. Indeed, it is known that some of these animals may act as reservoirs of zoonotic pathogens and thus be able to spread and transmit them to family members, along with their AMR, through their shared environment. It is therefore imperative to address this concern with the involvement of human, animal and environmental health professionals. This pilot study aimed to assess the prevalence and AMR patterns of Staphylococcus spp. strains obtained from commensal mucosal and skin infection samples in NTC small mammals, with a focus on strains like methicillin-resistant Staphylococcus spp. (MRS) that are critical in public health. Methods: For this purpose, 81 animals of different small mammal species were sampled, assessing antimicrobial susceptibility to 27 relevant antimicrobial agents (AMAs) in human health using minimum inhibitory concentration assays, and interpreting them according to EUCAST and CLSI guidelines. The isolated Staphylococci strains were identified by MALDI-TOF, with the predominant species being Mammalicoccus sciuri and Staphylococcus aureus. Results and discussion: Including all strains isolated, AMR was observed against all 27 AMAs, including six last-resort AMAs in human medicine. Additionally, over 85% of the strains exhibited MDR. These findings underscore the need to monitor AMR and MDR trends in companion animals and emphasise the potential role of NTCAs in spreading resistance to humans, other animals, and their shared environment, calling for a comprehensive "One Health" approach.

6.
Zoology (Jena) ; 166: 126195, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39128254

RESUMEN

For small non-hibernating mammals, a high thermogenic capacity is important to increase activity levels in the cold. It has been previously reported that lactating females decrease their thermogenic activity of brown adipose tissue (BAT), whereas their capacity to cope with extreme cold remains uncertain. In this study we examined food intake, body temperature and locomotor behavior, resting metabolic rate, non-shivering thermogenesis, and cytochrome c oxidase activity, and the rate of state 4 respiration of liver, skeletal muscle, and BAT in striped hamsters (Cricetulus barabensis) at peak lactation and non- breeding hamsters (controls). The lactating hamsters and non- breeding controls were acutely exposed to -15°C, and several markers indicative of thermogenic capacity were examined. In comparison to non-breeding females, lactating hamsters significantly increased food intake and body temperature, but decreased locomotor behavior, and the BAT mass, indicative of decreased BAT thermogenesis at peak lactation. Unexpectedly, lactating hamsters showed similar body temperature, resting metabolic rate, non-shivering thermogenesis with non-breeding females after acute exposure to -15°C. Furthermore, cytochrome c oxidase activity of liver, skeletal muscle and BAT, and serum thyroid hormone concentration, and BAT uncoupling protein 1 expression, in lactating hamsters were similar with that in non-breeding hamsters after acute extreme cold exposure. This suggests that lactating females have the same thermogenic capacity to survive cold temperatures compared to non-breeding animals. This is particularly important for females in the field to cope with cold environments during the period of reproduction. Our findings indicate that the females during lactation, one of the highest energy requirement periods, do not impair their thermogenic capacity in response to acute cold exposure.


Asunto(s)
Frío , Lactancia , Termogénesis , Animales , Femenino , Termogénesis/fisiología , Lactancia/fisiología , Cricetulus/fisiología , Cricetinae/fisiología , Tejido Adiposo Pardo/fisiología , Tejido Adiposo Pardo/metabolismo
7.
Int J Radiat Biol ; 100(10): 1405-1415, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39186765

RESUMEN

The incident of Chernobyl Nuclear Power Plant (CNPP) explosion has pioneered a plethora of studies unfolding various biological effects of radiation stress on several living systems. Determining radiation dose rates at which both acute and chronic biological effects occur in different biological systems will aid in the ex-situ generation of radiation-tolerant organisms. So far, the accumulation of data on different radiation doses from Chernobyl area demonstrating various biological impacts has not been documented altogether vastly. Therefore, this review aims to document the recorded doses in CNPP over the years at which different biological changes have been observed in plants, soil, aquatic organisms, birds, and animals. A total of 72 peer-reviewed papers obtained from PubMed, Google Scholar, Scopus, and Research4life were included in this review. A few factors have come under attention in this review. Firstly, plant and soil systems combinedly showed the most published studies after the catastrophe where plants showed a higher frequency of DNA methylation in their genome to resist radiation stress. Secondly, reduced species abundance, chromosomal aberrations, increased sterility, and mortality were mostly observed in the aftermath of Chernobyl catastrophe among plants, soil, aquatic organisms, birds, and small mammals. Furthermore, major scares of data after 2018 were prominently observed. Very few studies on radiation dose levels after 2018 are available. Hence, a major research area has emerged for radiation biologists to study present radiation levels and any genetic changes in the recent generation of the original victim species. This will help provide a standard dataset that can act as a reference resource for radiation biologists and future research on the impact of both acute and chronic radiation on the different biological systems.


Asunto(s)
Accidente Nuclear de Chernóbil , Animales , Humanos , Plantas/efectos de la radiación , Aves , Aberraciones Cromosómicas/efectos de la radiación , Organismos Acuáticos/efectos de la radiación
8.
Microsc Res Tech ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39126422

RESUMEN

Sperm morphology is considered the best indicator of male fertility. In Neotropical bats, important aspects of sperm morphology have been scantly studied. The aim of the present study was to characterize and compare the sperm morphology and morphometry of Artibeus planirostris and Sturnira erythromos. A total of 11 specimens were analyzed from the Colección de Mamíferos Lillo: five A. planirostris and six S. erythromos. The fixed epididymis were extracted and macerated in Farmer's solution, followed by the routine cytological procedure with different stains. To carry out the description and morphometric analysis, microphotographs were taken under an optical, epifluorescence and scanning electron microscope. A total of 50 sperm from each individual were measured for morphometric analysis. The percentage of normal/abnormal spermatozoa was estimated and the sperm abnormalities were classified. Both species showed morphologically simple spermatozoa with a spatulate head, a short neck, a helical midpiece and a tail that tapers at the final end, similar to other species of Phyllostomidae. The differences observed were: apex of the head was conical in A. planirostris and was oval in S. erythromos; longer head and midpiece in S. erythomos and longer sperm in A. planirostris. Both species showed a high percentage of sperm with normal appearance: 65% for A. planirostris and 72% for S. erythromos. The main sperm abnormalities were: scattered tails and heads, coiled tails, folded midpieces and presence of cytoplasmic droplets. The present work will improve the understanding of their reproductive biology. RESEARCH HIGHLIGHTS: Morphological descriptions and morphometric analyses of the sperm of Artibeus planirostris and Sturnira erythromos were carried out with optical, epifluorescence and scanning electron microscopy.

9.
Appl Environ Microbiol ; 90(8): e0084224, 2024 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-39058027

RESUMEN

Bartonella spp. are intracellular bacteria associated with several re-emerging human diseases. Small mammals play a significant role in the maintenance and spread of Bartonella spp. Despite the high small mammal biodiversity in South Africa, there is limited epidemiological information regarding Bartonella spp. in these mammals. The main aim of this study was to determine the prevalence and genetic diversity of Bartonella spp. from wild small mammals from 15 localities in 8 provinces of South Africa. Small mammals (n = 183) were trapped in the Eastern Cape, Free State, Gauteng, Limpopo, Mpumalanga, Northern Cape, North West, and Western Cape provinces of South Africa between 2010 and 2018. Heart, kidney, liver, lung, and spleen were harvested for Bartonella DNA screening, and prevalence was determined based on the PCR amplification of partial fragments of the 16S-23S rRNA intergenic spacer (ITS) region, gltA, and rpoB genes. Bartonella DNA was detected in Aethomys chrysophilus, Aethomys ineptus, Gerbillurus spp., Lemniscomys rosalia, Mastomys coucha, Micaelamys namaquensis, Rhabdomys pumilio, and Thallomys paedulcus. An overall prevalence of 16.9% (31/183, 95% CI: 12.2%-23%) was observed. Bartonella elizabethae, Bartonella grahamii, and Bartonella tribocorum were the zoonotic species identified, while the remaining sequences were aligned to uncultured Bartonella spp. with unknown zoonotic potential. Phylogenetic analyses confirmed five distinct Bartonella lineages (I-V), with lineage IV displaying strong M. coucha host specificity. Our results confirm that South African wild small mammals are natural reservoirs of a diverse assemblage of Bartonella spp., including some zoonotic species with high genetic diversity, although prevalence was relatively low.IMPORTANCESmall mammals play a significant role in the maintenance and spread of zoonotic pathogens such as Bartonella spp. Despite the high small mammal biodiversity in southern Africa including South Africa, there is limited epidemiological information regarding Bartonella spp. in these mammals across the country. Results from our study showed the liver and spleen had the highest positive cases for Bartonella spp. DNA among the tested organs. Bartonella elizabethae, B. grahamii, and B. tribocorum were the three zoonotic species identified and five distinct Bartonella lineages (I-V) were confirmed through phylogenetic analyses. To the best of our knowledge, this study presents the first extensive nuclear diversity investigation of Bartonella spp. in South African small mammals in South Africa.


Asunto(s)
Infecciones por Bartonella , Bartonella , Variación Genética , Bartonella/genética , Bartonella/aislamiento & purificación , Bartonella/clasificación , Sudáfrica/epidemiología , Animales , Infecciones por Bartonella/epidemiología , Infecciones por Bartonella/microbiología , Infecciones por Bartonella/veterinaria , Prevalencia , Filogenia , Animales Salvajes/microbiología , ADN Bacteriano/genética
10.
Ecology ; 105(9): e4384, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39039740

RESUMEN

Seasonal variation in animal activity influences fitness and the intensity of ecological interactions (e.g., competition, predation), yet aspects of global change in the Anthropocene may catalyze shifts in seasonal activity. Invasive plants are components of global change and can modify animal daily activity, but their influence on animal seasonal activity is less understood. We examined how invasive woody shrubs (Autumn olive [Elaeagnus umbellata] and Amur honeysuckle [Lonicera maackii]) affect seasonal activity of three common small-mammal species by coupling experimental shrub removal with autumnal camera trapping for two consecutive years at six paired forest sites (total 12 plots). Eastern chipmunks (Tamias striatus) foraged more, and foraging was observed at least 20 days longer, in shrub-invaded forests. White-footed mice (Peromyscus leucopus) foraged more in invaded than cleared plots in one study year, but P. leucopus autumn activity timing did not differ between shrub-removal treatments. Fox squirrel (Sciurus niger) activity displayed year-specific responses to shrub removal suggesting intraannual cues (e.g., temperature) structure S. niger autumnal activity. Our work highlights how plant invasions can have species-specific effects on seasonal animal activity, may modify the timing of physiological processes (e.g., torpor), and could generate variation in animal-mediated interactions such as seed dispersal or granivory.


Asunto(s)
Especies Introducidas , Lonicera , Estaciones del Año , Animales , Lonicera/fisiología , Sciuridae/fisiología , Elaeagnaceae/fisiología , Especificidad de la Especie , Conducta Alimentaria
11.
Pathogens ; 13(7)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-39057785

RESUMEN

We aimed to investigate the species composition of a small mammal community and the prevalence of Echinococcus spp. in a typical endemic area of the Tibetan Plateau. One pika and five rodent species were identified based on the morphological characteristics of 1278 small mammal specimens collected during 2014-2019. Detection of Echinococcus DNA in tissue samples from small mammal specimens revealed that Ochotona curzoniae (pika, total prevalence: 6.02%, 26/432), Neodon fuscus (5.91%, 38/643), N. leucurus (2.50%, 3/120), and Alexandromys limnophilus (21.74%, 10/46) were infected by both E. multilocularis and E. shiquicus; Cricetulus longicaudatus (16.67%, 1/6) was infected by E. shiquicus; and no infection was detected in N. irene (0/15). Neodon fuscus and O. curzoniae were the two most abundant small mammal species. There was no significant difference in the prevalence of pika and the overall rodent species assemblage (6.26%, 53/846); however, the larger rodent populations suggested that more attention should be paid to their role in the transmission of echinococcosis in the wildlife reservoir, which has long been underestimated. Moreover, although DNA barcoding provides a more efficient method than traditional morphological methods for identifying large numbers of small mammal samples, commonly used barcodes failed to distinguish the three Neodon species in this study. The close genetic relationships between these species suggest the need to develop more powerful molecular taxonomic tools.

12.
PeerJ ; 12: e17818, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39076772

RESUMEN

Linear infrastructures such as agricultural irrigation channels produce physical changes and negative impacts to habitats, wildlife populations, communities, and ecosystems. Open irrigation channels act as a pitfall for wildlife and can affect vertebrates of all sizes. Nonetheless, small channels have received relatively little attention by conservation biologists. The objective of this study was to analyze vertebrate species richness and mortality in relation to different sections of an irrigation channel system and the surrounding landscape characteristics. For two years, we conducted monthly surveys along an open-channel irrigation system to estimate its effect on vertebrates through records of dead and alive individuals. We examined the spatial relation of species richness and mortality with transects using a canonical correspondence analysis and chi-squared tests to determine possible variations in the different structures of the channel and seasonality. Further, a landscape diversity index was used to analyze the importance of surrounding habitat structure and composition on these parameters. Most vertebrates (61%) were found dead, small mammals and reptiles were the most affected. Our results indicate that mortality of small vertebrates varies depending on species, structures of the open-channel agricultural irrigation system (i.e., concrete channel and floodgates), seasonality (i.e., wet, and dry), and landscape heterogeneity (i.e., high, medium, and low landscape diversity). The open-channel irrigation system is a threat to populations of small vertebrates in anthropized landscapes, conservation efforts should be directed at protecting water bodies and restructuring the open-channel agricultural irrigation system to avoid mortality of species such as small rodents (M. mexicanus) and reptiles (C. triseriatus, B. imbricata, and Thamnophis spp.).


Asunto(s)
Riego Agrícola , Ecosistema , Vertebrados , Animales , México , Biodiversidad , Estaciones del Año , Conservación de los Recursos Naturales/métodos , Agricultura/métodos
13.
J Anim Ecol ; 93(8): 1065-1077, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38932441

RESUMEN

Unravelling the intricate mechanisms that govern community coexistence remains a daunting challenge, particularly amidst ongoing environmental change. Individual physiology and metabolism are often studied to understand the response of individual animals to environmental change. However, this perspective is currently largely lacking in community ecology. We argue that the integration of individual metabolism into community theory can offer new insights into coexistence. We present the first individual-based metabolic community model for a terrestrial mammal community to simulate energy dynamics and home range behaviour in different environments. Using this model, we investigate how ecologically similar species coexist and maintain their energy balance under food competition. Only if individuals of different species are able to balance their incoming and outgoing energy over the long-term will they be able to coexist. After thoroughly testing and validating the model against real-world patterns such as of home range dynamics and field metabolic rates, we applied it as a case study to scenarios of habitat fragmentation - a widely discussed topic in biodiversity research. First, comparing single-species simulations with community simulations, we find that the effect of habitat fragmentation on populations is strongly context-dependent. While populations of species living alone in the landscape were mostly positively affected by fragmentation, the diversity of a community of species was highest under medium fragmentation scenarios. Under medium fragmentation, energy balance and reproductive investment were also most similar among species. We therefore suggest that similarity in energy balance among species promotes coexistence. We argue that energetics should be part of community ecology theory, as the relative energetic status and reproductive investment can reveal why and under what environmental conditions coexistence is likely to occur. As a result, landscapes can potentially be protected and designed to maximize coexistence. The metabolic community model presented here can be a promising tool to investigate other scenarios of environmental change or other species communities to further disentangle global change effects and preserve biodiversity.


Asunto(s)
Biodiversidad , Metabolismo Energético , Modelos Biológicos , Animales , Mamíferos/fisiología , Ecosistema , Fenómenos de Retorno al Lugar Habitual
14.
Integr Zool ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858802

RESUMEN

We inferred the patterns of co-occurrence of flea species in compound (across all host species) and component (across conspecific hosts) communities from six regions of the world (Mongolia, Northwest Argentina, Argentinian Patagonia, West Siberia, Slovakia, and South Africa) using the novel eigenvector ellipsoid method. This method allows us to infer structural community patterns by comparing species' environmental requirements with the pattern of their co-occurrences. We asked whether: (a) communities are characterized by species segregation, nestedness, or modularity; (b) patterns detected by the novel method conform to the patterns identified by traditional methods that search for non-randomness in community structure; and (c) the pattern of flea species co-occurrences in component communities is associated with host species traits. The results of the application of the eigenvector ellipsoid method suggested that the co-occurrence of flea species was random in all compound communities except in South Africa, where this community demonstrated a tendency to be nested. Flea species co-occurrences were random in many component communities. Species segregation was detected in the flea community of one host, whereas the flea communities of 14 hosts from different regions appeared to be nested. No indication of a modular structure in any community was found. The nestedness of flea component communities was mainly characteristic of hosts with a low relative brain mass. We concluded that the application of this novel method that combines data on species distribution and their environmental requirements allows better identification of the community structural patterns and produces more reliable results as compared with traditional methods.

15.
Animals (Basel) ; 14(11)2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38891733

RESUMEN

The body condition index (BCI) is an indicator of both reproductive success and health in small mammals and might help to understand ecological roles of species. We analyzed BCI data from 28,567 individuals trapped in Lithuania between 1980 and 2023. We compared BCIs between species and examined differences in age groups, gender, and reproductive statuses within each species. Seven out of eighteen species had sample sizes with N < 100. In terms of species, we found that seven of the eight species with the highest average BCIs are granivores or omnivores, which can consume animal-based food at least seasonally. The two contrasting (decreasing or increasing) BCI patterns observed during ontogeny can be related to diet differences among juveniles, subadults, and adult animals. Our results demonstrate that reproductive stress has a negative impact on the BCI of adult females in all analyzed species and nearly all adult males. Although the animals with extremely low BCI consisted mostly of shrews, for the first time we found 23 common and pygmy shrews exhibiting the Chitty effect, i.e., a very high body mass resulting in a BCI > 5.0. This is the first multi-species approach of body condition at middle latitudes. The results increase our understanding of how changing environmental conditions are affecting small mammals.

16.
Ecology ; 105(7): e4333, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38826028

RESUMEN

Habitat loss and change are often implicated as the primary causes of species extinction. Although any population can be instantly imperiled by catastrophe, most habitat loss occurs gradually, thus enabling affected individuals an adaptive advantage to occupy the best of their dwindling opportunities. I demonstrate how to infer the advantage between two habitats for any density and frequency-dependent strategy of habitat selection. I explore the concept of an Adaptive Dispersal Strategy Landscape to reveal the Evolutionarily Stable Strategy separately for ideal-free and ideal preemptive habitat selectors. Both solutions reveal an initially counterintuitive expectation that individuals living at high density gain insufficient adaptive advantage to disperse from a deteriorating habitat. Adaptive dispersal is constrained at high density because habitats of better quality are fully occupied. I test the theory with measures of movement and foraging in crossover experiments on a seminatural population of meadow voles. The experiment allowed the voles to choose among patches and between enclosures in which I differentially manipulated food and shelter. Although photographs from an infrared camera documented voles venturing from one habitat to the other, none became resident. Voles preferentially foraged in the richer of the two enclosures, even when I reversed treatments, and they foraged more in patches protected by mulched straw. The adaptive advantage of dispersal using a surrogate fitness proxy based on the voles' giving-up densities mirrored that generated by theory. The convergence between theory and experiment yields much-needed insight into our ability to test, predict, and hopefully resolve, the ecological, evolutionary, and conservation consequences of habitat loss.


Asunto(s)
Ecosistema , Animales , Arvicolinae/fisiología , Adaptación Fisiológica , Modelos Biológicos
17.
Prev Vet Med ; 229: 106228, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38850871

RESUMEN

To prevent foodborne infections from pigs and cattle, the whole food chain must act to minimize the contamination of products, including biosecurity measures which prevent infections via feed and the environment in production farms. Rodents and other small mammals can be reservoirs of and key vectors for transmitting zoonotic bacteria and viruses to farm animals, through direct contact but more often through environmental contamination. In line with One Health concept, we integrated results from a sampling study of small mammals in farm environments and data from a capture-recapture experiment into a probabilistic model which quantifies the degree of environmental exposure of zoonotic bacteria by small mammals to farm premises. We investigated more than 1200 small mammals trapped in and around 38 swine and cattle farm premises in Finland in 2017/2018. Regardless of the farm type, the most common species caught were the yellow-necked mouse (Apodemus flavicollis), bank vole (Clethrionomys glareolus), and house mouse (Mus musculus). Of 554 intestine samples (each pooled from 1 to 10 individuals), 33% were positive for Campylobacter jejuni. Yersinia enterocolitica was detected in 8% of the pooled samples, on 21/38 farm premises. Findings of Salmonella and the Shiga-toxin producing Escherichia coli (STEC) were rare: the pathogens were detected in only single samples from four and six farm premises, respectively. The prevalence of Campylobacter, Salmonella, Yersinia and STEC in small mammal populations was estimated as 26%/13%, 1%/0%, 2%/3%, 1%/1%, respectively, in 2017/2018. The exposure probability within the experimental period of four weeks on farms was 17-60% for Campylobacter and 0-3% for Salmonella. The quantitative model is readily applicable to similar integrative studies. Our results indicate that small mammals increase the risk of exposure to zoonotic bacteria in animal production farms, thus increasing risks also for livestock and human health.


Asunto(s)
Enfermedades de los Bovinos , Enfermedades de los Porcinos , Animales , Bovinos , Porcinos , Prevalencia , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/microbiología , Enfermedades de los Porcinos/prevención & control , Enfermedades de los Porcinos/transmisión , Finlandia/epidemiología , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/transmisión , Roedores/microbiología , Zoonosis Bacterianas/epidemiología , Zoonosis Bacterianas/microbiología , Zoonosis/epidemiología , Reservorios de Enfermedades/veterinaria , Reservorios de Enfermedades/microbiología , Medición de Riesgo , Granjas
18.
Vet Clin North Am Exot Anim Pract ; 27(3): 503-519, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38692942

RESUMEN

The objective of this clinical retrospective study was to analyze the prevalence and distribution of different avian and exotic animals presented to 2 exotics-only veterinary hospital in Hong Kong and Taiwan over a 1 year period. Exotic companion mammals, predominated by rabbits (Oryctolagus cuniculus) that were often diagnosed with fractures, were the most commonly presented group of patients in the hospital in Hong Kong while second most of that in Taiwan, with dental disease being commonly presented in the species. This study provided a general overview of avian and exotic patients presented to exotics-only practices in the East Asia region.


Asunto(s)
Animales Exóticos , Hospitales Veterinarios , Animales , Estudios Retrospectivos , Hong Kong/epidemiología , Taiwán/epidemiología , Enfermedades de las Aves/epidemiología , Aves
19.
Environ Sci Pollut Res Int ; 31(22): 33155-33162, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38733443

RESUMEN

Plastic pollution in terrestrial and freshwater environments and its accumulation along food chains has been poorly studied in birds. The Barn owl (Tyto alba) is an opportunistic and nocturnal apex predator feeding mostly on small mammals. In this note, we reported evidence of microplastics (MPs) contamination in Barn owl pellets collected, for the first time, in two sites with different levels of anthropization (low: natural landscape mosaic vs. high extensive croplands). The following polymers have been recorded: polyvinylchloride (PVC), polyethylene (PE), expanded polyester (EPS), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyester (PL), viscose, and starch-based biopolymer. We found significant higher MPs frequency in the most anthropized site. Our results suggest that pellet' analysis may represent a cost-effective method for monitoring MP contamination along food chains in terrestrial ecosystems.


Asunto(s)
Monitoreo del Ambiente , Microplásticos , Estrigiformes , Animales , Microplásticos/análisis , Cadena Alimentaria , Ecosistema
20.
Ecol Evol ; 14(5): e11450, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38783847

RESUMEN

Fire shapes animal communities by altering resource availability and species interactions, including between predators and prey. In Australia, there is particular concern that two highly damaging invasive predators, the feral cat (Felis catus) and European red fox (Vulpes vulpes), increase their activity in recently burnt areas and exert greater predation pressure on the native prey due to their increased exposure. We tested how prescribed fire occurrence and extent, along with fire history, vegetation, topography, and distance to anthropogenic features (towns and farms), affected the activity (detection frequency) of cats, foxes, and the native mammal community in south-eastern Australia. We used camera traps to quantify mammal activity before and after a prescribed burn and statistically tested how the fire interacted with these habitat variables to affect mammal activity. We found little evidence that the prescribed fire influenced the activity of cats and foxes and no evidence of an effect on kangaroo or small mammal (<800 g) activity. Medium-sized mammals (800-2000 g) were negatively associated with prescribed fire extent, suggesting that prescribed fire has a negative impact on these species in the short term. The lack of a clear activity increase from cats and foxes is likely a positive outcome from a fire management perspective. However, we highlight that their response is likely dependent upon factors like fire size, severity, and prey availability. Future experiments should incorporate GPS-trackers to record fine-scale movements of cats and foxes in temperate ecosystems immediately before and after prescribed fire to best inform management within protected areas.

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