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1.
R Soc Open Sci ; 11(5): 231938, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-39076792

RESUMO

Wildlife demography is influenced by behavioural decisions, with sleep being a crucial avian behaviour. Avian species use roost sites to minimize thermoregulation costs, predation risk and enhance foraging efficiency. Sleep locations are often reused, forming networks within the home range. Our study, focusing on female eastern wild turkeys (Meleagris gallopavo silvestris) during the reproductive season, used social network analysis to quantify both roost site selection and network structure. We identified roost networks which were composed of a small percentage of hub roost sites connecting satellite roosts. Hub roosts were characterized by greater values of betweenness (ß = 0.62, s.e. = 0.02), closeness (ß = 0.59, s.e. = 0.03) and eigenvalue centrality (ß = 1.15, s.e. = 0.05), indicating their importance as connectors and proximity to the network's functional centre. The probability of a roost being a hub increased significantly with greater eigenvalue centrality. Female wild turkeys consistently chose roost sites at lower elevations and with greater topographical ruggedness. Hub roost probability was higher near secondary roads and further from water. Our research highlights well-organized roost site networks around hub roosts, emphasizing the importance of further investigations into how these networks influence conspecific interactions, reproduction and resource utilization in wild turkeys.

2.
PeerJ ; 12: e17457, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38854793

RESUMO

For many species, the relationship between space use and diet composition is complex, with individuals adopting varying space use strategies such as territoriality to facilitate resource acquisition. Coyotes (Canis latrans) exhibit two disparate types of space use; defending mutually exclusive territories (residents) or moving nomadically across landscapes (transients). Resident coyotes have increased access to familiar food resources, thus improved foraging opportunities to compensate for the energetic costs of defending territories. Conversely, transients do not defend territories and are able to redirect energetic costs of territorial defense towards extensive movements in search of mates and breeding opportunities. These differences in space use attributed to different behavioral strategies likely influence foraging and ultimately diet composition, but these relationships have not been well studied. We investigated diet composition of resident and transient coyotes in the southeastern United States by pairing individual space use patterns with analysis of stable carbon (δ13C) and nitrogen (δ15N) isotope values to assess diet. During 2016-2017, we monitored 41 coyotes (26 residents, 15 transients) with GPS radio-collars along the Savannah River area in the southeastern United States. We observed a canopy effect on δ13C values and little anthropogenic food in coyote diets, suggesting 13C enrichment is likely more influenced by reduced canopy cover than consumption of human foods. We also observed other land cover effects, such as agricultural cover and road density, on δ15N values as well as reduced space used by coyotes, suggesting that cover types and localized, resident-like space use can influence the degree of carnivory in coyotes. Finally, diets and niche space did not differ between resident and transient coyotes despite differences observed in the proportional contribution of potential food sources to their diets. Although our stable isotope mixing models detected differences between the diets of resident and transient coyotes, both relied mostly on mammalian prey (52.8%, SD = 15.9 for residents, 42.0%, SD = 15.6 for transients). Resident coyotes consumed more game birds (21.3%, SD = 11.6 vs 13.7%, SD = 8.8) and less fruit (10.5%, SD = 6.9 vs 21.3%, SD = 10.7) and insects (7.2%, SD = 4.7 vs 14.3%, SD = 8.5) than did transients. Our findings indicate that coyote populations fall on a feeding continuum of omnivory to carnivory in which variability in feeding strategies is influenced by land cover characteristics and space use behaviors.


Assuntos
Coiotes , Isótopos de Nitrogênio , Coiotes/fisiologia , Animais , Isótopos de Nitrogênio/análise , Isótopos de Carbono/análise , Carnivoridade , Dieta , Territorialidade , Sudeste dos Estados Unidos , Comportamento Alimentar/fisiologia
3.
Ecol Evol ; 14(5): e11390, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38770129

RESUMO

Ten state wildlife management agencies in the United States, including six within the Southeast, have delayed their spring wild turkey (Meleagris gallopavo) hunting seasons since 2017 by five or more days to address concerns related to the potential effects of hunting on wild turkey seasonal productivity. One hypothesis posits that if the spring hunting season is too early, there may be insufficient time for males to breed hens before being harvested, thus leading to reduced seasonal productivity. We conducted an experiment to determine whether delaying the wild turkey hunting season by 2 weeks in south-middle Tennessee would affect various reproductive rates. In 2021 and 2022, the Tennessee Fish and Wildlife Commission experimentally delayed the spring hunting season to open 14 days later than the traditional date (the Saturday closest to 1 April) in Giles, Lawrence, and Wayne counties. We monitored reproductive rates from 2017 to 2022 in these three counties as well as two adjacent counties, Bedford and Maury, that were not delayed. We used a Before-After-Control-Impact design to analyze the proportion of hens nesting, clutch size, hatchability, nest success, poult survival and hen survival with linear mixed-effect models and AIC model selection to detect relationships between the 14-day delay and reproductive parameters. We detected no relationship (p > .05) between the 14-day delay and any individual reproductive parameter. In addition, recruitment (hen poults per hen that survived until the next breeding season) was very low (<0.5) and did not increase because of the 14-day delay. The traditional Tennessee start date had been in place since 1986 while the turkey harvest increased markedly until about 2006 and more recently stabilized. Our data indicate that moving the start of the hunting season from a period just prior to peak nest initiation to 2 weeks later, to coincide with a period just prior to peak nest incubation initiation, resulted in no change to productivity or populations in wild turkey flocks in south-middle Tennessee.

4.
Ecol Evol ; 14(4): e11302, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38681182

RESUMO

Males of species with promiscuous mating systems are commonly observed to use larger ranges during the mating season relative to non-mating seasons, which is often attributed to a change in movements related to reproductive activities. However, few studies link seasonal range sizes to variation in daily space use patterns to provide insight into the behavioral mechanisms underlying mating season range expansion. We studied 20 GPS-tagged male wild turkeys (Meleagris gallopavo), a large upland gamebird, during the mating and summer non-mating seasons to test the hypothesis that larger mating season ranges resulted from male wild turkeys expanding the scale of daily movement activities to locate and court females. We delineated mating and non-mating seasons based on intensity of gobbling, a vocalization tied to courtship behavior, recorded by autonomous recording units distributed across the study area. Mating season ranges were significantly larger than non-mating season ranges. Daily ranges were larger in the mating season, as were distances between roost sites used on consecutive nights. Variance in daily range size was greater in the mating season, but low temporal autocorrelation suggested considerable daily variability in both seasons. We found no evidence that male wild turkeys changed how they distributed daily movements within seasonal ranges, or differences in habitat use, suggesting larger mating season ranges result from male wild turkeys increasing the scale of their daily movements, rather than a systematic shift to a nomadic movement strategy. Likely, the distribution of females is more dynamic and ephemeral compared to other resources, prompting males to traverse larger daily ranges during the mating season to locate and court females. Our work illustrates the utility of using daily movement to understand the behavioral process underlying larger space use patterns.

5.
Mov Ecol ; 12(1): 4, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38229127

RESUMO

BACKGROUND: Central place foragers must acquire resources and return to a central location after foraging bouts. During the egg laying (hereafter laying) period, females are constrained to a nest location, thus they must familiarize themselves with resources available within their incubation ranges after nest site selection. Use of prospecting behaviors by individuals to obtain knowledge and identify profitable (e.g., resource rich) locations on the landscape can impact demographic outcomes. As such, prospecting has been used to evaluate nest site quality both before and during the reproductive period for a variety of species. METHODS: Using GPS data collected from female eastern wild turkeys (Meleagris gallopavo silvestris) across the southeastern United States, we evaluated if prospecting behaviors were occurring during laying and what landcover factors influenced prospecting. Specifically, we quantified areas prospected during the laying period using a cluster analysis and the return frequency (e.g., recess movements) to clustered laying patches (150-m diameter buffer around a clustered laying period location) during the incubation period. RESULTS: The average proportion of recess movements to prospected locations was 56.9%. Nest fate was positively influenced (µ of posterior distribution with 95% credible 0.19, 0.06-0.37, probability of direction = 99.8%) by the number of patches (90-m diameter buffer around a clustered laying period location) a female visited during incubation recesses. Females selected for areas closer to the nest site, secondary roads, hardwood forest, mixed pine-hardwood forest, water, and shrub/scrub, whereas they avoided pine forest and open-treeless areas. CONCLUSIONS: Our findings suggest that having a diverse suite of clustered laying patches to support incubation recesses is impactful to nest fate. As such, local conditions within prospected locations during incubation may be key to successful reproductive output by wild turkeys. We suggest that prospecting could be important to other phenological periods. Furthermore, future research should evaluate how prospecting for brood-rearing locations may occur before or during the incubation period.

6.
J Wildl Dis ; 60(1): 139-150, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37972643

RESUMO

Lymphoproliferative disease virus (LPDV) and reticuloendotheliosis virus (REV) are oncogenic retroviruses that can cause disease in wild and domestic fowl. Lymphoproliferative disease virus infections are common and widespread in Wild Turkeys (Meleagris gallopavo) in the US and east-central Canada, while REV has been detected worldwide in numerous avian host species. We tested tissues (spleen, liver, and/or bone marrow, plus neoplastic tissue, if present) from 172 Wild Turkeys that underwent necropsy from December 2018 through October 2021 for both viruses using PCR. We evaluated demographic, geographic, temporal, and seasonal data by chi-square test of independence and logistic regression for turkeys infected with LPDV and/or REV. At least one of these retroviruses was detected in 80.8% (139/172) of Wild Turkeys from 15 US states, with significantly more turkeys being positive for LPDV (72.1%, 124/172) versus REV (43.6%, 75/172; P<0.001). Both viruses (coinfections) were detected in 34.9% (60/172) of turkeys. Among LPDV-infected turkeys (including coinfections), bone marrow had the highest detection rate (38/58, 65.5%), significantly higher than spleen (30/58, 51.7%) and liver (20/58, 34.5%; P<0.001). In REV-infected turkeys, bone marrow had the highest detection rate (24/58, 41.4%). All three tissues (spleen, liver, bone marrow) concurrently tested positive in most (15/25, 60%) REV-infected turkeys. These results suggest LPDV tissue tropism for bone marrow, whereas REV may have broader tissue tropism. Histopathology consistent with lymphoid proliferation and/or neoplasia characteristic of lymphoproliferative disease was evident in 29/172 (16.9%) turkeys assessed, including two REV-only-infected turkeys. Season was significantly associated with LPDV prevalence (highest in winter); year and season were both significantly associated with REV prevalence (highest in 2020 and winter). These data contribute to optimizing diagnostic strategies that may aid in pathogen monitoring and improve detections to increase our understanding of the potential impacts of these viruses on Wild Turkey populations.


Assuntos
Alpharetrovirus , Doenças das Aves , Coinfecção , Vírus da Reticuloendoteliose , Animais , Coinfecção/veterinária , Doenças das Aves/epidemiologia , Retroviridae , Perus
7.
J Wildl Dis ; 59(4): 767-773, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37486883

RESUMO

A Eurasian strain of H5N1 highly pathogenic avian influenza virus (HPAIV) was first detected in North America in December 2021 and has since been confirmed in numerous wild and domestic avian species. In April 2022, 41 Wild Turkeys (Meleagris gallopavo) were found dead in Johnson County, Wyoming, USA adjacent to a property with confirmed HPAIV in a backyard poultry flock. Oropharyngeal swabs were collected from 11 of the 41 turkeys and necropsy was performed on seven. Avian influenza virus RNA was detected in all 11 turkeys by real-time reverse-transcription PCR. Acute, multiorgan necrosis was observed grossly and identified in all seven turkeys evaluated by histopathology, most consistently in the lung, spleen, liver, gastrointestinal tract, and gonads. Lesions indicate high virulence of subclade 2.3.4.4b H5N1 HPAIV in Wild Turkeys, with infections presenting as clusters of acute mortality. Although documented cases of HPAIV in Wild Turkeys are rare, these findings signify a risk of spillback from domestic poultry, which may be heightened by the recent rise in backyard poultry ownership and the use of peridomestic habitat by wild birds. Additional research is needed to better understand the risk of disease transmission at the interface of Wild Turkeys and backyard poultry and the potential conservation and management implications of HPAIV in wild gallinaceous birds.


Assuntos
Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Animais , Influenza Aviária/epidemiologia , Virus da Influenza A Subtipo H5N1/genética , Perus , Aves Domésticas , Animais Selvagens , Aves
8.
Ecol Evol ; 13(6): e10171, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37325717

RESUMO

Coordination in timing of reproduction is driven by multiple ecological and sociobiological processes for a wide array of species. Eastern wild turkeys (Meleagris gallopavo silvestris) use a male dominance polygynous mating system, where males communicate with females via elaborate courtship displays and vocalizations at display sites. Most females prefer to mate with dominant males; therefore, asynchronous breeding and nesting may occur which can disproportionately influence individual fitness within breeding groups. For female wild turkeys, there are reproductive advantages associated with earlier nesting. As such, we evaluated reproductive asynchrony within and between groups of GPS-tagged female eastern wild turkeys based on timing of nest initiation. We examined 30 social groups with an average of seven females per group (range 2-15) during 2014-2019 in west central Louisiana. We found that the estimated number of days between first nest initiation across females within groups varied between 3 and 7 days across years, although we expected 1-2 days to occur between successive nesting attempts of females within groups based on observations of captive wild turkeys in the extant literature. The number of days between successive nest attempts across females within groups was lower for successful than failed attempts, and nests with an average of 2.8 days between initiation of another nest were more likely to hatch. Our findings suggest that asynchronous reproduction may influence reproductive success in female wild turkeys.

9.
J Vet Diagn Invest ; 35(4): 399-403, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37129000

RESUMO

The effects of filter paper strip (FPS) storage time and temperature on antibody detection are poorly understood despite widespread use in wildlife research. We collected sera and FPSs from 23 wild turkeys (Meleagris gallopavo) and 20 northern bobwhites (Colinus virginianus) experimentally infected with West Nile virus (WNV) to compare FPS storage methods with WNV plaque reduction neutralization test (PRNT) sensitivity. FPS storage methods included: immediate elution after drying, and storage at -20°C for 3 mo, -20°C for 6 mo, room temperature (RT) for 3 mo, and RT for 6 mo prior to elution. FPS eluates and sera were co-titrated to determine endpoint antibody titers, which were compared between FPS sera eluted immediately and sera, and among FPS eluates that underwent different storage conditions. Antibody titers were ~4-fold less in FPS sera eluted immediately versus sera, and dropped more frequently below PRNT detection threshold in northern bobwhites, which had ~10-fold lower serum antibody titers than wild turkeys. Antibody titers were lower in FPS samples stored at RT and for 6 mo. WNV serologic surveys may result in falsely low seroprevalence estimates if FPSs are stored at RT for ≥ 3 mo before elution.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Temperatura , Estudos Soroepidemiológicos , Anticorpos Antivirais , Animais Selvagens , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária
10.
Ecol Evol ; 13(2): e9830, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36844669

RESUMO

Recent declines in eastern wild turkeys (Meleagris gallopavo silvestris) have prompted increased interest in management and research of this important game species. However, the mechanisms underlying these declines are unclear, leaving uncertainty in how best to manage this species. Foundational to effective management of wildlife species is understanding the biotic and abiotic factors that influence demographic parameters and the contribution of vital rates to population growth. Our objectives for this study were to (1) conduct a literature review to collect all published vital rates for eastern wild turkey over the last 50 years, (2) perform a scoping review of the biotic and abiotic factors that have been studied relative to wild turkey vital rates and highlight areas that require additional research, and (3) use the published vital rates to populate a life-stage simulation analysis (LSA) and identify the vital rates that make the greatest contribution to population growth. Based on published vital rates for eastern wild turkey, we estimated a mean asymptotic population growth rate (λ) of 0.91 (95% CI = 0.71, 1.12). Vital rates associated with after-second-year (ASY) females were most influential in determining population growth. Survival of ASY females had the greatest elasticity (0.53), while reproduction of ASY females had lower elasticity (0.21), but high process variance, causing it to explain a greater proportion of variance in λ. Our scoping review found that most research has focused on the effects of habitat characteristics at nest sites and the direct effects of harvest on adult survival, while research on topics such as disease, weather, predators, or anthropogenic activity on vital rates has received less attention. We recommend that future research take a more mechanistic approach to understanding variation in wild turkey vital rates as this will assist managers in determining the most appropriate management approach.

11.
Ecol Appl ; 33(1): e2734, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36057107

RESUMO

For wide-ranging species in temperate environments, populations at high-latitude range limits are subject to more extreme conditions, colder temperatures, and greater snow accumulation compared with their core range. As climate change progresses, these bounding pressures may become more moderate on average, while extreme weather occurs more frequently. Individuals can mitigate temporarily extreme conditions by changing daily activity budgets and exhibiting plasticity in resource selection, both of which facilitate existence at and expansion of high-latitude range boundaries. However, relatively little work has explored how animals moderate movement and vary resource selection with changing weather, and a general framework for such investigations is lacking. We applied hidden Markov models and step selection functions to GPS data from wintering wild turkeys (Meleagris gallopavo) near their northern range limit to identify how weather influenced transition among discrete movement states, as well as state-specific resource selection. We found that turkeys were more likely to spend time in a stationary state as wind chill temperatures decreased and snow depth increased. Both stationary and roosting turkeys selected conifer forests and avoided land covers associated with foraging, such as agriculture and residential areas, while shifting their strength of selection for these features during poor weather. In contrast, mobile turkeys showed relatively weak resource selection, with less response in selection coefficients during poor weather. Our findings illustrate that behavioral plasticity in response to weather was context dependent, but movement behaviors most associated with poor weather were also those in which resource selection was most plastic. Given our results, the potential for wild turkey range expansion will partly be determined by the availability of habitat that allows them to withstand periodic inclement weather. Combining hidden Markov models with step selection functions is broadly applicable for evaluating plasticity in animal behavior and dynamic resource selection in response to changing weather. We studied turkeys at northern range limits, but this approach is applicable for any system expected to experience significant changes in the coming decade, and may be particularly relevant to populations existing at range peripheries.


Assuntos
Perus , Tempo (Meteorologia) , Animais , Perus/fisiologia , Estações do Ano , Temperatura , Ecossistema
12.
Avian Pathol ; 51(6): 601-612, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36102057

RESUMO

Since the introduction of West Nile virus (WNV) to North America in 1999, WNV is estimated to have contributed to population-level declines in numerous avian species. However, the potential impacts of this virus on many free-ranging upland game bird species, including the wild turkey (Meleagris gallopavo), which is undergoing regional population declines, remain unknown. Herein, two age groups (∼5 to 6 weeks and ∼15 to 16 weeks post-hatch) of juvenile wild turkeys were subcutaneously inoculated with WNV, sampled daily from 1 to 7 days post-inoculation (dpi), and euthanized on 14 dpi. No clinical signs and minimal gross lesions were attributable to WNV infection. Peak viraemia titres were similar between age groups (<101.7 to 104.6 plaque-forming units [PFU]/ml), but the duration of viraemia was longer in the old group (3-4 days) than in the young group (0-3 days). Intermittent oral and/or cloacal viral shedding from 2 to 7 dpi was detected in both age groups. No infectious virus was detected in the heart, brain, kidney, skeletal muscle, spleen, and feathers from WNV-inoculated turkeys euthanized on 14 dpi. All WNV-inoculated birds seroconverted by 14 dpi, as well as two co-housed sham-inoculated birds. The most consistent microscopic lesions among all WNV-inoculated birds were mild lymphoplasmacytic myocarditis and encephalitis. Minimal immunohistochemical labelling was detected in tissues in addition to scant macrophages within the blood, spleen, and bone marrow. These data suggest WNV is unlikely to pose a significant risk to wild turkey populations, although the possibility remains that WNV may indirectly decrease fitness or predispose wild turkeys to other health stressors.RESEARCH HIGHLIGHTS Clinical disease was not observed in wild turkeys experimentally infected with WNV.Pathology attributed to WNV was mild and included brain and heart inflammation.Viraemias suggest WNV-infected wild turkeys do not play a role in WNV transmission.No age-associated differences in WNV clinical disease or pathology were observed.


Assuntos
Doenças das Aves , Doenças das Aves Domésticas , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Febre do Nilo Ocidental/veterinária , Febre do Nilo Ocidental/patologia , Viremia/veterinária , Perus , Aves
13.
J Wildl Dis ; 58(4): 725-734, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35951026

RESUMO

A Merriam's Wild Turkey (Meleagris gallopavo merriami) with periocular swelling and periocular skin crusting in Pueblo County, Colorado, USA, was diagnosed with severe catarrhal and fibrinous sinusitis and conjunctivitis. A novel clade of Avibacterium was detected in the exudate from this bird. Although eight additional turkeys culled from the affected flock did not have clinical signs or gross lesions, histologically all had mild-to-moderate chronic sinusitis, and infraorbital cultures yielded the same novel clade of Avibacterium that was found in the symptomatic turkey. The presence of this Avibacterium species in the absence of significant disease in some birds suggested that other factors might have been involved in the development of severe sinusitis and conjunctivitis in the symptomatic Wild Turkey. Negative culture results from a distant flock of Wild Turkeys, acquired with similar methods to the affected flock, suggested that this novel species of Avibacterium was not widespread throughout Wild Turkeys in Colorado.


Assuntos
Animais , Colorado/epidemiologia
14.
Ecol Evol ; 12(6): e9018, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35784066

RESUMO

Gobbling activity of Eastern wild turkeys (Meleagris gallopavo silvestris; hereafter, turkeys) has been widely studied, focusing on drivers of daily variation. Weather variables are widely believed to influence gobbling activity, but results across studies are contradictory and often equivocal, leading to uncertainty in the relative contribution of weather variables to daily fluctuations in gobbling activity. Previous works relied on road-based auditory surveys to collect gobbling data, which limits data consistency, duration, and quantity due to logistical difficulties associated with human observers and restricted sampling frames. Development of new methods using autonomous recording units (ARUs) allows researchers to collect continuous data in more locations for longer periods of time, providing the opportunity to delve into factors influencing daily gobbling activity. We used ARUs from 1 March to 31 May to detail gobbling activity across multiple study sites in the southeastern United States during 2014-2018. We used state-space modeling to investigate the effects of weather variables on daily gobbling activity. Our findings suggest rainfall, greater wind speeds, and greater temperatures negatively affected gobbling activity, whereas increasing barometric pressure positively affected gobbling activity. Therefore, when using daily gobbling activity to make inferences relative to gobbling chronology, reproductive phenology, and hunting season frameworks, stakeholders should recognize and consider the potential influences of extended periods of inclement weather.

15.
J Wildl Dis ; 58(3): 537-549, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35704504

RESUMO

Growing populations of Wild Turkeys (Meleagris gallopavo) may result in increased disease transmission among wildlife and spillover to poultry. Lymphoproliferative disease virus (LPDV) is an avian retrovirus that is widespread in Wild Turkeys of eastern North America, and infections may influence mortality and parasite co-infections. We aimed to identify individual and spatial risk factors of LPDV in Maine's Wild Turkeys. We also surveyed for co-infections between LPDV and reticuloendotheliosis virus (REV), Mycoplasma gallisepticum, and Salmonella pullorum to estimate trends in prevalence and examine covariance with LPDV. From 2017 to 2020, we sampled tissues from hunter-harvested (n=72) and live-captured (n=627) Wild Turkeys, in spring and winter, respectively, for molecular detection of LPDV and REV. In a subset of captured individuals (n=235), we estimated seroprevalence of the bacteria M. gallisepticum and S. pullorum using a plate agglutination test. Infection rates for LPDV and REV were 59% and 16% respectively, with a co-infection rate of 10%. Seroprevalence for M. gallisepticum and S. pullorum were 74% and 3.4%, with LPDV co-infection rates of 51% and 2.6%, respectively. Infection with LPDV and seroprevalence of M. gallisepticum and S. pullorum decreased, whereas REV infection increased, between 2018 and 2020. Females (64%), adults (72%), and individuals sampled in spring (76%) had higher risks of LPDV infection than males (47%), juveniles (39%), and individuals sampled in winter (57%). Furthermore, LPDV infection increased with percent forested cover (ß=0.014±0.007) and decreased with percent agriculture cover for juveniles (ß=-0.061±0.018) sampled in winter. These data enhance our understanding of individual and spatial predictors of LPDV infection in Wild Turkeys and aid in assessing the associated risk to Wild Turkey populations and poultry operations.


Assuntos
Alpharetrovirus , Doenças das Aves , Coinfecção , Vírus da Reticuloendoteliose , Viroses , Animais , Animais Selvagens , Doenças das Aves/epidemiologia , Coinfecção/epidemiologia , Coinfecção/veterinária , Feminino , Masculino , Aves Domésticas , Estudos Soroepidemiológicos , Perus , Viroses/veterinária
16.
Appl Environ Microbiol ; 88(5): e0142321, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35044852

RESUMO

Turkeys (Meleagris gallopavo) provide a globally important source of protein and constitute the second most important source of poultry meat in the world. Bacterial diseases are common in commercial poultry production, causing significant production losses for farmers. Due to the increasingly recognized problems associated with large-scale/indiscriminate antibiotic use in agricultural settings, poultry producers need alternative methods to control common bacterial pathogens. In this study, we compared the cecal microbiota of wild and domestic turkeys, hypothesizing that environmental pressures faced by wild birds may select for a disease-resistant microbial community. Sequence analyses of 16S rRNA genes amplified from cecal samples indicate that free-roaming wild turkeys carry a rich and variable microbiota compared to domestic turkeys raised on large-scale poultry farms. Wild turkeys also had very low levels of Staphylococcus, Salmonella, and Escherichia coli compared to domestic turkeys. E. coli strains isolated from wild and domestic turkey cecal samples also belong to distinct phylogenetic backgrounds and differ in their propensity to carry virulence genes. E. coli strains isolated from factory-raised turkeys were far more likely to carry genes for capsule (kpsII and kpsIII) or siderophore (iroN and fyuA) synthesis than were those isolated from wild turkeys. These results suggest that the microbiota of wild turkeys may provide colonization resistance against common poultry pathogens. IMPORTANCE Due to the increasingly recognized problems associated with antibiotic use in agricultural settings, poultry producers need alternative methods to control common bacterial pathogens. In this study, we compare the microbiota of wild and domestic turkeys. The results suggest that free-ranging wild turkeys carry a distinct microbiome compared to farm-raised turkeys. The microbiome of wild birds contains very low levels of poultry pathogens compared to that of farm-raised birds. The microbiomes of wild turkeys may be used to guide the development of new ways to control disease in large-scale poultry production.


Assuntos
Microbioma Gastrointestinal , Doenças das Aves Domésticas , Animais , Escherichia coli , Filogenia , Doenças das Aves Domésticas/microbiologia , Prevalência , RNA Ribossômico 16S/genética , Perus/microbiologia
17.
Animals (Basel) ; 11(7)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206329

RESUMO

Selection for increased muscle mass in domestic turkeys has resulted in muscles twice the size of those found in wild turkeys. This study characterizes muscle structural changes as well as functional differences in muscle performance associated with selection for increased muscle mass. We compared peak isometric force production, whole muscle and individual fiber cross-sectional area (CSA), connective tissue collagen concentration and structure of the lateral gastrocnemius (LG) muscle in wild and adult domestic turkeys. We also explored changes with age between juvenile and adult domestic turkeys. We found that the domestic turkey's LG muscle can produce the same force per cross-sectional area as a wild turkey; however, due to scaling, domestic adults produce less force per unit body mass. Domestic turkey muscle fibers were slightly smaller in CSA (3802 ± 2223 µm2) than those of the wild turkey (4014 ± 1831 µm2, p = 0.013), indicating that the absolutely larger domestic turkey muscles are a result of an increased number of smaller fibers. Collagen concentration in domestic turkey muscle (4.19 ± 1.58 µg hydroxyproline/mg muscle) was significantly lower than in the wild turkeys (6.23 ± 0.63 µg/mg, p = 0.0275), with visible differences in endomysium texture, observed via scanning electron microscopy. Selection for increased muscle mass has altered the structure of the LG muscle; however, scaling likely contributes more to hind limb functional differences observed in the domestic turkey.

18.
Ticks Tick Borne Dis ; 12(3): 101675, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33529986

RESUMO

The lone star tick, Amblyomma americanum, is a common human-biting species whose range has been largely restricted to the southeastern United States, until recent detections of established populations on Long Island, New York and throughout coastal southern New England. We evaluated the effectiveness of topical treatment of 10 % permethrin delivered via 4-poster devices to white-tailed deer, Odocoileus virginianus, in the management of a newly discovered A. americanum population in Norwalk, Connecticut. Using a high-density deployment of one 4-poster device/12.7 ha, we were successful in significantly reducing densities of host-seeking adults (93 % reduction), nymphs (92 %), and larvae (96 %) from 2018 to 2020. We also documented a significant reduction (87 %) in parasitizing adults and nymphs on white-tailed deer from 2018 to 2019. The prevalence of Ehrlichia chaffeensis and Ehrlichia ewingii combined in host-seeking adults declined significantly from 47 % at the time the A. americanum population was discovered in 2017 to 7% in 2020. However, the prevalence in nymphs remained static (∼9%) throughout the study period. These data demonstrate that, when properly deployed in a density-dependent manner in terms of deer abundance, 4-poster devices can effectively manage parasitizing and host-seeking A. americanum populations and reduce the prevalence of two ehrlichial species of public health importance.


Assuntos
Acaricidas , Amblyomma , Ehrlichia chaffeensis/fisiologia , Ehrlichia/fisiologia , Permetrina , Controle de Ácaros e Carrapatos , Amblyomma/crescimento & desenvolvimento , Amblyomma/microbiologia , Animais , Connecticut , Cervos/parasitologia , Feminino , Larva/crescimento & desenvolvimento , Larva/microbiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia
19.
Ecol Evol ; 11(24): 18248-18270, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35003671

RESUMO

Extensive restoration and translocation efforts beginning in the mid-20th century helped to reestablish eastern wild turkeys (Meleagris gallopavo silvestris) throughout their ancestral range. The adaptability of wild turkeys resulted in further population expansion in regions that were considered unfavorable during initial reintroductions across the northern United States. Identification and understanding of species distributions and contemporary habitat associations are important for guiding effective conservation and management strategies across different ecological landscapes. To investigate differences in wild turkey distribution across two contrasting regions, heavily forested northern Wisconsin, USA, and predominately agricultural southeast Wisconsin, we conducted 3050 gobbling call-count surveys from March to May of 2014-2018 and used multiseason correlated-replicate occupancy models to evaluate occupancy-habitat associations and distributions of wild turkeys in each study region. Detection probabilities varied widely and were influenced by sampling period, time of day, and wind speed. Spatial autocorrelation between successive stations was prevalent along survey routes but was stronger in our northern study area. In heavily forested northern Wisconsin, turkeys were more likely to occupy areas characterized by moderate availability of open land cover. Conversely, large agricultural fields decreased the likelihood of turkey occupancy in southeast Wisconsin, but occupancy probability increased as upland hardwood forest cover became more aggregated on the landscape. Turkeys in northern Wisconsin were more likely to occupy landscapes with less snow cover and a higher percentage of row crops planted in corn. However, we were unable to find supporting evidence in either study area that the abandonment of turkeys from survey routes was associated with snow depth or with the percentage of agricultural cover. Spatially, model-predicted estimates of patch-specific occupancy indicated turkey distribution was nonuniform across northern and southeast Wisconsin. Our findings demonstrated that the environmental constraints of turkey occupancy varied across the latitudinal gradient of the state with open cover, snow, and row crops being influential in the north, and agricultural areas and hardwood forest cover important in the southeast. These forces contribute to nonstationarity in wild turkey-environment relationships. Key habitat-occupancy associations identified in our results can be used to prioritize and strategically target management efforts and resources in areas that are more likely to harbor sustainable turkey populations.

20.
Ecol Evol ; 10(20): 11752-11765, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33144998

RESUMO

Females must balance physiological and behavioral demands of producing offspring with associated expenditures, such as resource acquisition and predator avoidance. Nest success is an important parameter underlying avian population dynamics. Galliforms are particularly susceptible to low nest success due to exposure of ground nests to multiple predator guilds, lengthy incubation periods, and substantive reliance on crypsis for survival. Hence, it is plausible that nesting individuals prioritize productivity and survival differently, resulting in a gradient of reproductive strategies. Fine-scale movement patterns during incubation are not well documented in ground-nesting birds, and the influence of reproductive movements on survival is largely unknown. Using GPS data collected from female wild turkeys (n = 278) across the southeastern United States, we evaluated the influence of incubation recess behaviors on trade-offs between nest and female survival. We quantified daily recess behaviors including recess duration, recess frequency, total distance traveled, and incubation range size for each nest attempt as well as covariates for nest concealment, nest attempt, and nest age. Of 374 nests, 91 (24%) hatched and 39 (14%) females were depredated during incubation. Average nest survival during the incubation period was 0.19, whereas average female survival was 0.78. On average, females took 1.6 daily unique recesses (SD = 1.2), spent 2.1 hr off the nest each day (SD = 1.8), and traveled 357.6 m during recesses (SD = 396.6). Average nest concealment was 92.5 cm (SD = 47). We found that females who took longer recess bouts had higher individual survival, but had increased nest loss. Females who recessed more frequently had lower individual survival. Our findings suggest behavioral decisions made during incubation represent life-history trade-offs between predation risk and reproductive success on an unpredictable landscape.

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