The study of ecology and horses involves examining the interactions between horses and their environments, including both natural and managed ecosystems. This field explores how horses influence and are influenced by various ecological factors such as vegetation, soil, water sources, and other animal species. Research in this area may address topics such as the grazing behavior of horses, their impact on plant communities, and the role of horses in nutrient cycling within ecosystems. Additionally, studies may investigate the effects of environmental changes and human activities on horse populations and their habitats. This page compiles peer-reviewed research studies and scholarly articles that analyze the ecological roles of horses, their interactions with ecosystems, and the implications for conservation and land management.
Campaigners are working hard to preserve access routes through the countryside for ramblers, dog walkers and horse riders. They invite you to join them. reports.
Tang L, Li Y, Srivathsan A, Gao Y, Li K, Hu D, Zhang D.Captivity maybe the only choice for survival of many endangered vertebrates, and understanding its broad effects is important for animal management and conservation, including breeding endangered species for subsequent release. Extreme environmental changes during captivity may influence survival ability in the wild. Captivity decreases gut bacterial diversity in a wide range of animals. However, most studies directly compare animals living in captivity with those in the wild, and there is a lack of understanding of effects of gradient shift in lifestyle during species reintroduction based on ...
Garrido P, Edenius L, Mikusiński G, Skarin A, Jansson A, Thulin CG.Large herbivores play key roles in terrestrial ecosystems. Continuous defaunation processes have produced cascade effects on plant community composition, vegetation structure, and even climate. Wood-pastures were created by traditional management practices that have maintained open structures and biodiversity for millennia. In Europe, despite the broad recognition of their biological importance, such landscapes are declining due to land-use changes. This calls for finding urgent solutions for wood-pasture conservation. To test whether introducing an ecological replacement of an extinct wild ho...
Lim QL, Tan YL, Ng WL, Yong CSY, Ismail A, Rovie-Ryan JJ, Rosli N, Annavi G.A molecular sexing method by polymerase chain reaction (PCR) amplification of a portion of the sex-determining region Y (SRY) and the zinc finger (ZF) gene, as well as six equine Y-chromosome-specific microsatellite markers, were tested in the Malayan tapir (Tapirus indicus). While the microsatellite markers did not yield any male-specific amplicons for sex-typing, the SRY/ZF marker system produced reliable molecular sexing results by accurately sex-typing 31 reference Malayan tapirs, using whole blood, dried blood spot (DBS), or tissue samples as materials for DNA extraction. The marker syste...
Vershinina AO, Kapp JD, Baryshnikov GF, Shapiro B.Museum collections are essential for reconstructing and understanding past biodiversity. Many museum specimens are, however, challenging to identify. Museum samples may be incomplete, have an unusual morphology, or represent juvenile individuals, all of which complicate accurate identification. In some cases, inaccurate identification can lead to false biogeographic reconstructions with cascading impacts on paleontological and paleoecological research. Here, we analyzed an unusual Equid mandible found in the Far North of the Taymyr peninsula that was identified morphologically as Equus hemionu...
Harvey AM, Beausoleil NJ, Ramp D, Mellor DJ.Knowledge of the welfare status of wild animals is vital for informing debates about the ways in which we interact with wild animals and their habitats. Currently, there is no published information about how to scientifically assess the welfare of free-roaming wild animals during their normal day-to-day lives. Using free-roaming horses as an example, we describe a ten-stage protocol for systematically and scientifically assessing the welfare of individual non-captive wild animals. The protocol starts by emphasising the importance of readers having an understanding of animal welfare in a conser...
Rzekęć A, Vial C, Bigot G.Despite the decline of equine populations in the middle of the 20th century, the European horse industry is growing again thanks to economic alternatives found in the diversification of the uses of equines (sports, racing, leisure, etc.). Equines have many environmental advantages, but the fragmentation of the sector and the lack of synthetic knowledge about their environmental impacts do not enable the promotion of these assets and their effective inclusion in management practices and European policies. To highlight the equine environmental impacts, a literature review was carried out to cove...
McDonnell S, Torcivia C.Feral horses, wherever managed, typically require population control involving capture for permanent removal or repeatedly for fertility control treatments. The most common method for capturing feral horses is helicopter chasing into traps. With this fear-based strategy, it is difficult to safely capture entire groups. Recapture becomes increasingly difficult, with greater safety risks for pilots and ground staff. As preliminary proof of the concept of capturing free-roaming horses by leading into enclosures with light aircraft rather than driving with helicopters, a consumer-grade quadcopter ...
Tarazona AM, Ceballos MC, Broom DM.Excessive human population growth, uncontrolled use of natural resources, including deforestation, mining, wasteful systems, biodiversity reduction by agriculture, and damaging climate change affect the existence of all animals, including humans. This discussion is now urgent and people are rethinking their links with the animals we use for clothing, food, work, companionship, entertainment, and research. The concepts of one health, one welfare, and one biology are discussed as a background to driving global change. Nothing should be exploited without considering the ethics of the action and t...
López-Sánchez A, Perea R, Roig S, Isselstein J, Schmitz A.Traditional orchard meadows are among the most valuable cultural and agricultural systems for nature conservation in Europe. They comprise scattered fruit trees over a highly diverse herbaceous layer and provide a wide range of ecosystem services. However, they are strongly endangered due to farmland intensification and abandonment. Livestock grazing is known to promote grassland diversity but it may also cause tree damage through debarking. In this study, we evaluated the effect of different grazers (cattle, horse and sheep) on fruit trees in 42 traditional orchards of the Rhenish uplands (Ge...
Orlando L.The horse was essential to past human societies but became a recreational animal during the twentieth century as the world became increasingly mechanized. As the author reviews here, recent studies of ancient genomes have revisited the understanding of horse domestication, from the very early stages to the most modern developments. They have uncovered several extinct lineages roaming the far ends of Eurasia some 4000 years ago. They have shown that the domestic horse has been significantly reshaped during the last millennium and experienced a sharp decline in genetic diversity within the last...
Ning T, Ling Y, Hu S, Ardalan A, Li J, Mitra B, Chaudhuri TK, Guan W, Zhao Q, Ma Y, Savolainen P, Zhang Y.Despite decades of research, the horse domestication scenario in East Asia remains poorly understood. The study identified 16 haplogroups with fine-scale phylogenetic resolution using mitochondrial genomes of 317 horse samples. The time to the most recent common ancestor of the 16 haplogroups ranges from [0.8-3.1] thousand years ago (KYA) to [7.9-27.1] KYA. With combined analyses of the mitochondrial control region for 35 extant Przewalski's horses, 3544 modern and 203 ancient horses across the world, researchers provide evidence for that East Asian prevalent haplogroups Q and R were indigenou...
Yang F, Shao Q, Jiang Z.Using the Yellow-River-Source National Park (YRSNP) as a study site, an unmanned aerial vehicle (UAV) remote sensing and line transect method was used to investigate the number of wild herbivorous animals and livestock, including the kiang () and Tibetan gazelle (). A downscaling algorithm was used to generate the forage yield data in YRSNP based on a 30-m spatial resolution. On this basis, we estimated the forage-livestock balance, which included both wild animals and livestock, and analyzed the effects of functional zone planning in national parks on the forage-livestock balance in YRSNP. Th...
Li Y, Zhang K, Liu Y, Li K, Hu D, Wronski T.Large and complex intestinal microbiota communities in hosts have profound effects on digestion and metabolism. To better understand the community structure of intestinal microbiota in Przewalski's horse () under different feeding regimes, we compared bacterial diversity and composition between captive and reintroduced Przewalski's horses, using high-throughput 16S-rRNA gene sequencing for identification. Reintroduced Przewalski's horses were sampled in two Chinese nature reserves, i.e., Dunhuang Xihu Nature Reserve (DXNR; = 8) in Gansu Province and Kalamaili Nature Reserve (KNR; = 12) in Xi...
Ringmark S, Skarin A, Jansson A.Horse grazing may benefit biodiversity, but the impact of year-round grazing on nutrient dynamics has not been evaluated previously. This study compared pasture quality in a forest-grassland landscape grazed year-round by horses with that in exclosed mown areas. Twelve Gotlandsruss stallions were kept without supplementary feeding in three enclosures (~0.35 horse/ha) outside Uppsala, Sweden, from May 2014 to September 2016. Each enclosure contained three mown exclosures, where grass sward samples were collected monthly and analyzed for chemical composition and vegetation density. Fecal grab sa...
Lazzerini N, Coulon A, Simon L, Marchina C, Noost B, Lepetz S, Zazzo A.Carbon and nitrogen stable isotope time series performed in continuously growing tissues (hair, tooth enamel) are commonly used to reconstruct the dietary history of modern and ancient animals. Predicting the effects of altitudinal mobility on animal δ C and δ N values remains difficult as several variables such as temperature, water availability or soil type can contribute to the isotope composition. Modern references adapted to the region of interest are therefore essential. Methods: Between June 2015 and July 2018, six free-ranging domestic horses living in the Mongolian Altaï were fitte...
McHorse BK, Biewener AA, Pierce SE.Horses are a classic example of macroevolution in three major traits-large body size, tall-crowned teeth (hypsodonty), and a single toe (monodactyly)-but how and why monodactyly evolved is still poorly understood. Existing hypotheses usually connect digit reduction in horses to the spread and eventual dominance of open-habitat grasslands, which took over from forests during the Cenozoic; digit reduction has been argued to be an adaptation for speed, locomotor economy, stability, and/or increased body size. In this review, we assess the evidence for these (not necessarily mutually exclusive) hy...
Mendonça RS, Ringhofer M, Pinto P, Inoue S, Hirata S.In the rapidly expanding field of comparative thanatology, reports from a wide range of taxa suggest that some aspects of a concept of death may be shared by many non-human species. In horses, there are only a few anecdotal reports on behaviors toward dead conspecifics, mostly concerning domestic individuals. Here, we describe the case of a 2-month-old, free-ranging male foal that died around 12 h after being found severely injured due to a presumed wolf attack, focusing on other individuals' reactions to the dying foal. We also placed camera traps near horse carcasses to investigate reaction...
Yang J, Wang Y, Cui X, Zhang Y, Yu Z.Huge numbers of microorganisms reside in livestock faeces and constitute one of the most complex microbial ecosystems. Here, faecal microbial communities of three typical livestock in Xilingol steppe grassland, i.e. sheep, cattle, and horse, were investigated by Illumina MiSeq sequencing and quantitative real-time polymerase chain reaction (qPCR). Firmicutes and Bacteroidetes comprised the majority of bacterial communities in three livestock faeces. Sordariomycetes, Leotiomycetes, and Dothideomycetes were dominant in fungal communities, as well as Methanobacteria and Methanomicrobia were domin...
Gold S, Regan CE, McLoughlin PD, Gilleard JS, Wilson AJ, Poissant J.Variability in host resistance or tolerance to parasites is nearly ubiquitous, and is of key significance in understanding the evolutionary processes shaping host-parasite interactions. While ample research has been conducted on the genetics of parasite burden in livestock, relatively little has been done in free-living populations. Here, we investigate the sources of (co)variation in strongyle nematode faecal egg count (FEC) and body condition in Sable Island horses, a feral population in which parasite burden has previously been shown to negatively correlate with body condition. We used the ...
Yan L, Zhang M, Tang L, Ente M, Ma X, Chu H, Li K, Hu D, Zhang D.Myiasis has great economic and medical importance. However, myiasis in wildlife that is caused by oestroid flies is relatively rarely recorded compared with that in humans and domestic animals. Recently, during our research on the conservation of Przewalski's horse (PH), we observed two new records of oestroid flies parasitizing wildlife in China. The first is the horse nasal bot fly, Rhinoestrus sp. (Diptera: Oestridae), found in a dead PH from Kalamaili Nature Reserve. One morphotype (R. purpureus-like) was identified. The second is the Wohlfahrt's wound myiasis fly, Wohlfahrtia magnifica (S...
Espunyes J, Lurgi M, Büntgen U, Bartolomé J, Calleja JA, Gálvez-Cerón A, Peñuelas J, Claramunt-López B, Serrano E.Changes in land-use and climate affect the distribution and diversity of plant and animal species at different spatiotemporal scales. The extent to which species-specific phenotypic plasticity and biotic interactions mediate organismal adaptation to changing environments, however, remains poorly understood. Woody plant expansion is threatening the extent of alpine grasslands worldwide, and evaluating and predicting its effects on herbivores is of crucial importance. Here, we explore the impact of shrubification on the feeding efficiency of Pyrenean chamois (Rupicapra p. pyrenaica), as well as ...
Equine infectious anaemia (EIA) is a disease with an almost worldwide distribution, with several outbreaks having been reported recently in European countries. In Italy, two regions, Lazio and Abruzzo, are considered as endemic areas for this disease. In nature, the EIA virus is mechanically transmitted by biting flies such as tabanids (Diptera: Tabanidae), although few studies have investigated the epidemiological implications. In the present study, several sites characterized by different levels of EIA prevalence were sampled. In sites with high tabanid populations, a seasonal succession of ...
Degeling C, Gilbert GL, Annand E, Taylor M, Walsh MG, Ward MP, Wilson A, Johnson J.Hendra virus (HeV) infection is endemic in Australian flying-fox populations. Habitat loss has increased the peri-urban presence of flying-foxes, increasing the risk of contact and therefore viral 'spillovers' into horse and human populations. An equine vaccine is available and horse-husbandry practices that minimize HeV exposure are encouraged, but their adoption is suboptimal. Ecological approaches-such as habitat creation and conservation-could complement vaccination and behavioural strategies by reducing spillover risks, but these are controversial. We convened three community juries (two ...
Antwis RE, Lea JMD, Unwin B, Shultz S.Microbiome composition is linked to host functional traits including metabolism and immune function. Drivers of microbiome composition are increasingly well-characterised; however, evidence of group-level microbiome convergence is limited and may represent a multi-level trait (i.e. across individuals and groups), whereby heritable phenotypes are influenced by social interactions. Here, we investigate the influence of spatial structuring and social interactions on the gut microbiome composition of Welsh mountain ponies. We show that semi-feral ponies exhibit variation in microbiome composition ...
Elghandour MMMY, Adegbeye MJ, Barbabosa-Pilego A, Perez NR, Hernández SR, Zaragoza-Bastida A, Salem AZM.Greenhouses gas emission mitigation is a very important aspect of earth sustainability with greenhouse gasses reduction, a focus of agricultural and petrochemical industries. Methane is produced in nonruminant herbivores such as horses because they undergo hindgut fermentation. Although equine produce less methane than ruminant, increasing population of horses might increase their contribution to the present 1.2 to 1.7 Tg, estimate. Diet, feeding frequency, season, genome, and protozoa population influence methane production equine. In population, Methanomicrobiales, Methanosarcinales, Methan...
Leonardi M, Boschin F, Giampoudakis K, Beyer RM, Krapp M, Bendrey R, Sommer R, Boscato P, Manica A, Nogues-Bravo D, Orlando L.Wild horses thrived across Eurasia until the Last Glacial Maximum to collapse after the beginning of the Holocene. The interplay of climate change, species adaptability to different environments, and human domestication in horse history is still lacking coherent continental-scale analysis integrating different lines of evidence. We assembled temporal and geographical information on 3070 horse occurrences across Eurasia, frequency data for 1120 archeological layers in Europe, and matched them to paleoclimatic and paleoenvironmental simulations for the Late Quaternary. Climate controlled the dis...
Machado G, Weiblen C, Escobar LE.Pythium insidiosum is a widespread pathogen that causes pythiosis, a disease with severe health consequences in horses and humans worldwide. Latin America hosts one of the largest, but scattered, horse herds, making it critical to identify areas at high risk of pythiosis transmission to help guide surveillance in areas with disease transmission risk. We utilized ecological niche modelling and epidemiological data to reconstruct the ecological conditions for pathogen circulation to identify areas with potential risk of pythiosis in Brazil and Uruguay. We surveyed 338 horse farm locations in sou...
Clutton-Brock TH, Greenwood PJ, Powell RP.Recent studies of primates have questioned the importance of dominance hierarchies in groups living under natural conditions. In a herd of Highland ponies and one of Highland cattle grazing under free-range conditions on the Isle of Rhum (Inner Hebrides) well defined hierarchies were present. The provision of food produced a marked increase in the frequency of agonistic interactions but had no effect on the rank systems of the two herds. While rank was clearly important in affecting the distribution of agonistic interactions, it was poorly related to behaviour in non-agonistic situations.
de Oliveira-Filho EF, Fischer C, Berneck BS, Carneiro IO, Kühne A, de Almeida Campos AC, Ribas JRL, Netto EM, Franke CR, Ulbert S, Drexler JF.Among 713 equids sampled in northeastern Brazil during 2013-2018, West Nile virus seroprevalence was 4.5% (95% CI 3.1%-6.3%). Mathematical modeling substantiated higher seroprevalence adjacent to an avian migratory route and in areas characterized by forest loss, implying increased risk for zoonotic infections in disturbed areas.
Shoemaker L, Clauset A.Horses (family Equidae) are a classic example of adaptive radiation, exhibiting a nearly 60-fold increase in maximum body mass and a peak taxonomic diversity of nearly 100 species across four continents. Such patterns are commonly attributed to niche competition, in which increased taxonomic diversity drives increased size disparity. However, neutral processes, such as macroevolutionary 'diffusion', can produce similar increases in disparity without increased diversity. Using a comprehensive database of Equidae species size estimates and a common mathematical framework, we measure the contribu...
Winton CL, Hegarty MJ, McMahon R, Slavov GT, McEwan NR, Davies-Morel MC, Morgan CM, Powell W, Nash DM.The conservation of unique populations of animals is critical in order to preserve valuable genetic diversity and, where populations are free-living, maintain their irreplaceable influence upon habitat ecology. An accurate assessment of genetic diversity and structure within and between populations is crucial in order to design and implement conservation strategies in natural and domesticated species. Moreover, where it is possible to identify relic populations that are related to a structured breed an ideal opportunity presents itself to model processes that reveal historical factors that hav...
Ringhofer M, Inoue S, Mendonça RS, Pereira C, Matsuzawa T, Hirata S, Yamamoto S.Horses are phylogenetically distant from primates, but considerable behavioral links exist between the two. The sociality of horses, characterized by group stability, is similar to that of primates, but different from that of many other ungulates. Although horses and primates are good models for exploring the evolution of societies in human and non-human animals, fewer studies have been conducted on the social system of horses than primates. Here, we investigated the social system of feral horses, particularly the determinant factors of single-male/multi-male group dichotomy, in light of hypot...
Sandoval-Castellanos E, Wutke S, Gonzalez-Salazar C, Ludwig A.Wild horses unexpectedly survived terminal Pleistocene megafaunal extinctions until eventual European extirpation in the twentieth century. This survival is tied to either their occurrence in cryptic open habitats or their adaptation to forests. Our niche modelling inferred an increasing presence of horses in post-glacial forests, and our analysis of ancient DNA suggested significant selection for black phenotypes as indicating adaptation to forests.
Liu SH, Hu DF, Li K.Oviposition site selection is an important aspect of the behavioural ecology of insects. A comparison of the habitats used by a species enhances our understanding of their adaptation to altered environments. We collected data on the oviposition behaviours of Gasterophilus pecorum (Diptera: Gasterophilidae) in its habitat in Kalamaili Nature Reserve (KNR), Xinjiang, China between March and October 2014. We found 91 quadrats were used by G. pecorum for oviposition. Examining 13 ecological factors using the t-test, chi-square test, and principal component analysis showed that G. pecorum's oviposi...
Kulikova EE, Isaeva AS, Rotkina AS, Manykin AA, Letarov AV.The complex cellulolytic microbial community of the horse intestines is a convenient model for studying the ecology of bacteriophages in natural habitats. Unlike the rumen of the ruminants, this community of the equine large intestine is not subjected to digestion. The inner conditions of the horse gut are much more stable in comparison to other mammals, due to the fact that the horse diet remains almost unchanged and the intervals between food consumption and defecation are much shorter than the whole digestive cycle. The results of preliminary analysis of the structure and dynamics of the vi...
Kennedy CR, Bush AO.Using data sets derived from published literature, the contribution of congeneric species to helminth component community richness is evaluated. Consideration of the frequency distribution of congeners in relation to host and parasite groups reveals that the distributions are unimodal, that singletons are the commonest class and that the frequency of occurrence of congeners decreases with increasing number of species per genus. Congeners may be found in any group of hosts or parasites, but are more common amongst cestodes of aquatic birds. Two patterns of occurrence of congeneric species are r...
Takasu M, Hiramatsu N, Tozaki T, Kakoi H, Hasegawa T, Maeda M, Kusuda S, Doi O, Murase T, Mukoyama H.The objective of this study was to clarify the current status of endangered Kiso horse, population statistics and biological traits, in order to take a step for the conservation by scientific approach. We surveyed 125 Kiso horses (86.2% of the whole breed), analyzed the construction of the population, and calculated the coefficient of inbreeding and effective population size. Moreover, we confirmed coat color variations and the traditional traits of the Kiso horse, and measured their height at the withers and chest circumference to clarify their physical characteristics. The population pyramid...
Törn A, Tolvanen A, Norokorpi Y, Tervo R, Siikamäki P.Nature-based tourism in protected areas has increased and diversified dramatically during the last decades. Different recreational activities have a range of impacts on natural environments. This paper reports results from a comparison of the impacts of hiking, cross-country skiing and horse riding on trail characteristics and vegetation in northern Finland. Widths and depths of existing trails, and vegetation on trails and in the neighbouring forests were monitored in two research sites during 2001 and 2002. Trail characteristics and vegetation were clearly related to the recreational activit...
Madejón P, Domínguez MT, Murillo JM.Pasture established on polluted soil may pose a risk to grazing livestock creating a requirement for mechanical management which may affect biodiversity and expend energy. The risk associated with managing pasture by grazing horses (non-edible livestock) is being assessed in the Guadiamar Valley (SW Spain), where soils are polluted with trace elements following a major pollution incident. Soil pollution does not affect biomass production or floristic composition of pasture, although both variables influence trace element accumulation in herbage. Element concentrations in herbage are below maxi...
Gold S, Regan CE, McLoughlin PD, Gilleard JS, Wilson AJ, Poissant J.Variability in host resistance or tolerance to parasites is nearly ubiquitous, and is of key significance in understanding the evolutionary processes shaping host-parasite interactions. While ample research has been conducted on the genetics of parasite burden in livestock, relatively little has been done in free-living populations. Here, we investigate the sources of (co)variation in strongyle nematode faecal egg count (FEC) and body condition in Sable Island horses, a feral population in which parasite burden has previously been shown to negatively correlate with body condition. We used the ...
Takai S, Fujimori T, Katsuzaki K, Tsubaki S.Quantitative culture of R. equi in the feces of dams and foals, in the air of the stalls and in the soil of the paddocks was carried out on three horse-breeding farms during the foaling season. The isolation rates of R. equi from the feces of dams from the 3 farms suddenly increased to approximately 80% at the end of March, when the snow in the paddocks finished melting, and remained at that level during April and May. The mean number of R. equi and the isolation rate of R. equi from the feces of dams on the farms were investigated for 5 weeks before and 5 weeks after delivery. During the 10 w...
Furtado T, King M, Perkins E, McGowan C, Chubbock S, Hannelly E, Rogers J, Pinchbeck G.Equestrian grazing management is a poorly researched area, despite potentially significant environmental impacts. This study explored keepers' use of alternative grazing systems in the care of UK horses, donkeys and mules through an internet survey. The survey was available during the summer of 2020 and comprised closed and open questions, which were analysed with descriptive statistics and iterative thematic analysis, respectively. A total of 758 responses was incorporated into the analysis; the most popular system used were tracks (56.5%), Equicentral (19%), "other" (e.g., non-grass turnout)...
Grange S, Duncan P, Gaillard JM.We investigated density dependence on the demographic parameters of a population of Camargue horses (Equus caballus), individually monitored and unmanaged for eight years. We also analysed the contributions of individual demographic parameters to changes in the population growth rates. The decrease in resources caused a loss of body condition. Adult male survival was not affected, but the survival of foals and adult females decreased with increasing density. Prime-aged females maintained high reproductive performance at high density, and their survival decreased. The higher survival of adult m...
Krüger K, Flauger B.Like many other herbivores, in a natural environment equids feed on rather evenly distributed resources. However, the vegetation in their vast habitats constantly changes. If food is plentiful only little competition occurs over food, and in non-competitive situations domestic horses tend to return to the same feeding site until it is overgrazed. In contrast, they compete over limited food for which the social status of the individuals appears to be important. Especially in ruminants several studies have proved an influence of social organisations, rank, sex and the depletion of feeding sites ...
Fuller A, Maloney SK, Kamerman PR, Mitchell G, Mitchell D.We used implanted miniature data loggers to measure brain and arterial blood temperatures in three free-ranging zebras (Equus burchelli) in their natural habitat, every 5 min for 9 days. The animals experienced globe temperatures exceeding 40 C, and radiant heat load of about 1000 W m-2. Arterial blood exhibited a moderate amplitude (1.7 C) nychthemeral rhythm, with an acrophase at 19.00 h and a nadir late in the morning, at 10.00 h. Brain temperature consistently exceeded blood temperature, on average by 0.2-0.4 C, and changes in brain temperature closely tracked changes in blood temperature....
Krishnan BS, Jones LR, Elmore JA, Samiappan S, Evans KO, Pfeiffer MB, Blackwell BF, Iglay RB.Visible and thermal images acquired from drones (unoccupied aircraft systems) have substantially improved animal monitoring. Combining complementary information from both image types provides a powerful approach for automating detection and classification of multiple animal species to augment drone surveys. We compared eight image fusion methods using thermal and visible drone images combined with two supervised deep learning models, to evaluate the detection and classification of white-tailed deer (Odocoileus virginianus), domestic cow (Bos taurus), and domestic horse (Equus caballus). We cla...
Wozniak A, Dowda HE, Tolson MW, Karabatsos N, Vaughan DR, Turner PE, Ortiz DI, Wills W.Arboviruses isolated and identified from mosquitoes in South Carolina (USA) are described, including new state records for eastern equine encephalitis virus (EEE), St. Louis encephalitis virus (SLE), Flanders virus, Tensaw virus (TEN), and a variant of Jamestown Canyon virus (JC). Mosquitoes were collected at 52 locations in 30 of 46 South Carolina counties beginning in June 1996, and ending in October 1998, and tested for arboviruses. Of 1,329 mosquito pools tested by virus isolation (85,806 mosquitoes representing 34 mosquito species or complexes), 15 pools were positive. Virus isolations in...
Stothart MR, McLoughlin PD, Medill SA, Greuel RJ, Wilson AJ, Poissant J.Gut microbiomes are widely hypothesised to influence host fitness and have been experimentally shown to affect host health and phenotypes under laboratory conditions. However, the extent to which they do so in free-living animal populations and the proximate mechanisms involved remain open questions. In this study, using long-term, individual-based life history and shallow shotgun metagenomic sequencing data (2394 fecal samples from 794 individuals collected between 2013-2019), we quantify relationships between gut microbiome variation and survival in a feral population of horses under natural...
Williams CA, Kenny LB, Weinert JR, Sullivan K, Meyer W, Robson MG.The objective of this study was to determine whether rotational grazing generates horse, pasture, or cost benefits over continuous grazing. The study established two replicates (1.57 ha each) of rotational (R; four grazing sections and a stress lot per replicate, where horses were fed a moderate quality grass hay at 2% of body weight when not grazing) and continuous (C) grazing systems (treatments). Twelve Standardbred mares were grazed for an overall stocking rate of 0.52 ha/horse ( = 3 in each pasture). Recommended management practices for each grazing system were followed for 27 mo includin...
El-Hage CM, Bamford NJ, Gilkerson JR, Lynch SE.Ross River virus (RRV) is a mosquito-borne arbovirus of the genus Alphavirus that causes disease in humans and horses in Australia. A temporal association of RRV infection in horses with clinical signs including pyrexia, malaise, and polyarthralgia has been reported, along with reduced athletic performance, often for extended periods. Despite these reports, disease due to RRV remains somewhat controversial as experimental infection of horses has resulted in obvious viraemia yet minimal signs of clinical disease. The relatively high viraemia demonstrated by horses infected with RRV has led to s...
Keiper RR.Socially feral horses live in stable social groups characterized by one adult male, a number of adult females, and their offspring up to 2 years of age. Extra males either live by themselves or with other males in bachelor groups. The bands occupy nondefended home ranges that often overlap. Many abnormal behaviors seen in domestic horses occur because some aspect of their normal social behavior cannot be carried out in captivity.
Lempereur L, Sohier C, Smeets F, Maréchal F, Berkvens D, Madder M, Francis F, Losson B.The dispersion potential of mechanical vectors is an important factor in the dissemination of pathogens. A mark-release-recapture experiment was implemented using two groups (unfed and partially fed) of the Tabanidae (Diptera) (Haematopota spp.) and biting Muscidae (Diptera) (Stomoxys calcitrans) most frequently collected in Belgium in order to evaluate their dispersion potential. In total, 2104 specimens of Haematopota spp. were collected directly from horses and 5396 S. calcitrans were collected in a cattle farm using hand-nets. Some of these insects were partially fed in vitro and all were ...
Richard E, Simpson SE, Medill SA, McLoughlin PD.Individual-based study of natural populations allows for accurate and precise estimation of fitness components and the extent to which they might vary with ecological conditions. By tracking the fates of all 701 horses known to have lived on Sable Island, Canada, from 2009 to 2013 (where there is no predation, human interference, or interspecific competition for food), we present a detailed analysis of structured population dynamics with focus on interacting effects of intraspecific competition and weather on reproduction and survival. Annual survival of adult females (0.866 ± 0.107 [[Formu...
Janczarek I, Stachurska A, Kędzierski W, Wiśniewska A, Ryżak M, Kozioł A.Predatory attacks on horses can become a problem in some parts of the world, particularly when considering the recovering gray wolf populations. The issue studied was whether horses transformed by humans and placed in stable-pasture environments had retained their natural abilities to respond to predation risk. The objective of the study was to determine the changes in cardiac activity, cortisol concentrations, and behavior of horses in response to the vocalizations of two predators: the gray wolf (Canis lupus), which the horses of the breed studied had coevolved with but not been exposed to r...
Geigl EM, Grange T.The Equidae have a long evolutionary history that has interested palaeontologists for a long time. Their morphology-based taxonomy, however, is a matter of controversy. Since most equid species are now extinct, the phylogenetic tree based on genetic data can be established only imperfectly via deduction of present day genomes and little is known about the past genetic diversity of these species. Recent studies of ancient DNA preserved in fossil bones have led to a simplification of the phylogenetic tree and the classification system. The situation is still particularly unclear for the wild ass...
Kaseda Y, Ogawa H, Khalil AM.Misaki feral horses were separated into 2 herds and the difference between dispersal from natal group (natal dispersal) and dispersal from natal area (natal emigration) was studied. The causes of dispersal and emigration and their effects on harem formation were studied 1979-1994. The number of horses ranged from 73 (mature males: 8, mature females: 26, young males: 8, young females: 3, colt foals: 6, filly foals: 10 and geldings: 12) in 1979 and 86 (mature males: 14, mature females: 37, young males: 12, young females: 7, colt foals: 5, filly foals: 7 and geldings: 4) in 1994 when the present ...
Ransom JI, Hobbs NT, Bruemmer J.Abiotic inputs such as photoperiod and temperature can regulate reproductive cyclicity in many species. When humans perturb this process by intervening in reproductive cycles, the ecological consequences may be profound. Trophic mismatches between birth pulse and resources in wildlife species may cascade toward decreased survival and threaten the viability of small populations. We followed feral horses (Equus caballus) in three populations for a longitudinal study of the transient immunocontraceptive porcine zona pellucida (PZP), and found that repeated vaccinations extended the duration of in...
