Meleagris Gallopavo Research Articles

The effect of the Stevia rebaudiana Morita II on the warts caused by fowl pox in Meleagris gallopavo as model study

O Objective: to evaluate the effect of leaves of Stevia rebaudiana Morita II on swelling caused by fowl pox in backyard turkeys of the Meleagris gallopavo species. Design/methodology/approach: Different percentages of ground stevia leaves (5.5, 15, 20 and 25%) combined with ground corn were evaluated and the reduction of avian pox in turkeys was evaluated. Results: The diet with 5% stevia leaves with corn was the most accepted combination by the turkeys; it also leads to immunomodulation to eliminate avian pox in a period of 30 days. Limitations on study/implications: One of the main limitations is the production of stevia matter, however, due to the required amount, it has the possibility of being applied in the feeding of these animals, this study has applications in animal health and food safety in turkeys. Findings/conclusions: The use of stevia in combination with corn could represent a natural alternative for the treatment of fowl pox and be profitable enough to prevent the death of turkeys.

Training in Vascular Microsurgery: The Ex Vivo Biological Model on Domestic Turkey Leg (Meleagris gallopavo).

There are various models for practicing microsurgical anastomoses, from synthetic to ex vivo and in vivo biological ones. In this study, we present the domestic turkey (Meleagris gallopavo) as an ex vivo biological model in the practice of surgical anastomoses. In our opinion, it represents a model that is very similar to a human one, low cost, and easy to find. In fact, our study shows that the diameters of the arteries and veins used for anastomoses (tibial artery diameter: 2.5 ± 0.6 mm; tibial vein diameter: 3.5 ± 1.2 mm) are similar to those of human arteries and veins most frequently used in microsurgical free flaps. So, we believe that this animal model is a great model for microsurgical training for doctors who approach this difficult and long to learn discipline.

Male mating season range expansion results from an increase in scale of daily movements for a polygynous-promiscuous bird.

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.

In silico genomic analysis of heat shock protein 70 in poultry under tropical conditions

The negative effect of climate change predisposes farm animals under tropical conditions to heat stress, which limit their productivity. This has necessitated the search for livestock with suitable adaptive genotype. Limited records exist for livestock with high genetic adaptability hence, selection for the most suitable breeding stock remain difficult. This study attempt to use genomic characteristics of heat shock protein 70 (HSP70) in common meat type birds as biomarker for selecting breeding stock of high genetic merit for tolerance. In silico expasy translate tool analysis revealed that heat shock protein 70 gene in chicken (Gallus gallus) and Japanese quail (Cortinux japonica) are on chromosome 30 and contain 2 and 3 exons linked to 67 and 45 introns, respectively while, in turkey (Meleagris gallopavo) and guinea fowl (Numida meleagris), HSP70 gene is located on chromosome 24 and 28, respectively. They also contain 2 and 4 exons interspersed by 41 and 38 introns, respectively. The variations in chromosomal locations validates differences observed in the adaptation and geographical spread of studied animals. It may also provide new insight into cellular response to heat stress and adaptive mechanism which is necessary in selection. Functional properties and physiological structures resisting thermal stress needs further investigation.

Investigating feather corticosterone and fault bars along the length of domestic male turkey (Meleagris gallopavo) feathers

Fault bars are visible deformities in the feather structure potentially related to the stress response and may be an interesting trait that can reflect robustness. This study’s objective was to describe fault bars along the length of domestic turkey feathers and investigate whether fault bars are associated with feather corticosterone (FCORT). The same primary wing feather was evaluated from 75 male turkeys from three genetic lines. Feathers were cut into three (proximal, middle, and distal) sections to score fault bar presence, incidence, and severity. FCORT was measured for each feather section using ELISA. Linear mixed models were used to investigate differences in the fault bar presence, incidence, and severity between feather sections and genetic line, as well as investigate associations between the fault bar measures and FCORT. There was a significant increase in FCORT and fault bar incidence from proximal to distal feather sections ( P < 0.0001). In the distal section only, sections with fault bars had significantly higher FCORT compared to sections without fault bars ( P = 0.0088). No associations were found between fault bars and FCORT in the other sections. Consequently, associating FCORT and fault bars using whole primary wing feathers may be challenging. Future work should reevaluate this relationship longitudinally to better understand fault bar development.

A proxy for brain-to-endocranial cavity index in non-neornithean dinosaurs and other extinct archosaurs.

Although the brain fills nearly the entire cranial cavity in birds, it can occupy a small portion of it in crocodilians. The lack of data regarding the volumetric correspondence between the brain and the cranial cavity hampers thorough assessments of the degree of encephalization in non-neornithean dinosaurs and other extinct archosaurs and, consequently, informed inferences regarding their cognitive capacities. Existing data suggest that, across extant archosaurs, the degree of endocranial doming and the volume of intracranial nonneural components are inversely related. We build upon this information to develop an equation relating these two anatomical features in non-neornithean dinosaurs and other extinct archosaurs. We rely on measurements of the endocast doming and brain-to-endocranial cavity (BEC) index in extant relatives of non-neornithean dinosaurs, namely, the crurotarsans Caiman crocodilus, Crocodylus niloticus, and Crocodylus porosus; the paleognaths Struthio camelus and Apteryx mantelli; and the fowl Macrocephalon maleo, Gallus gallus, Meleagris gallopavo, Phasianus colchicus, and Anas platyrhynchos. Applying the equation to representative endocasts from major clades of dinosaurs, we found that BEC varies from about 0.6 in ceratopsians and thyreophorans to around 0.7 in ornithopods, pachycephalosaurians, sauropods, and theropods. We, therefore, warn against the use of a catch-all value, like 0.5, and instead encourage refinement in the adoption of BEC across archosaurs.

Sex‐specific resource use by wild turkeys in response to hunting activity

AbstractHunting causes direct mortality and potentially disrupts normal activities of game and non‐game species. As spatial (i.e., selection of hunting areas) and temporal (i.e., only diurnally present) patterns of hunters can become predictable, hunted species may respond accordingly. Risk becomes more dynamic and complex for species that are hunted concurrent with their breeding cycle, and growing literature has noted that wild turkey (Meleagris gallopavo spp.) behaviors can be altered by hunting activity. We allocated global positioning system (GPS) units to 1,500 wild turkey hunters and affixed GPS transmitters to 175 wild turkeys during 2014–2018 on the Webb Wildlife Management Area Complex in South Carolina, USA. We evaluated whether wild turkeys shifted resource selection as a function of hunter resource selection during the progression of hunting seasons. Male wild turkeys avoided areas where stationary hunting bouts occurred during the early hunting season (and selected for these areas before hunting began), whereas females were more likely to select those areas avoided by males by the end of the hunting season. For every 15% increase in predicted probability of an area being hunted, male wild turkeys were 4.16 times less likely to select that area, whereas female wild turkeys were 1.08 times more likely to select that area relative to pre‐season periods when hunters were not on the landscape. Hunting activity induced immediate responses by male wild turkeys as they sought refuge away from hunted areas. Coupled with recent research suggesting hunters are more influential than natural predators in reducing the frequency of male vocalizations and eliciting fleeing and avoidance behavior, our results indicate hunting activity could affect distribution and courtship behaviors of male wild turkeys during their breeding season.

Experimental infection of domestic turkeys with lymphoproliferative disease virus of North American origin.

Lymphoproliferative disease virus (LPDV) was first documented in wild turkeys in North America in 2009. LPDV infection is often subclinical but can manifest as lymphoid proliferation or round cell neoplasia. Despite high prevalence across many sampled areas corresponding to declining populations of wild turkeys, knowledge regarding LPDV pathogenesis, risk factors for disease development, and associated impacts on population dynamics are unknown. To understand transmission, viral shedding, and tissue tropism, we inoculated 21 domestic turkeys via the oral cavity, crop, nasal cavity, subcutis, or coelomic cavity. For 12 weeks, oropharyngeal swabs, cloacal swabs, and whole blood were collected weekly. At 1 week postinoculation, 3 turkeys (3/21; 14%) had detectable LPDV proviral DNA in blood by polymerase chain reaction, and 10 developed DNAemia (50%; 10/20) by 12 weeks. LPDV proviral DNA was intermittently detected in oropharyngeal and cloacal swabs. Splenomegaly was the most consistent gross finding in DNAemic birds (8/11; 73%). Lymphoid hyperplasia in the spleen was the most significant microscopic finding (9/11; 82%). Three turkeys (3/11; 27%) developed round cell neoplasia characterized by sheets of pleomorphic, round to polygonal cells in the adrenal gland, bone marrow, skin, small intestine, and/or spleen. LPDV was detected in the spleen and bone marrow from all turkeys with DNAemia and all neoplasms. Our study establishes that infection and disease with North American LPDV from wild turkeys can be experimentally reproduced in domestic turkeys, laying the groundwork for future investigations into LPDV pathogenesis, development of diagnostic techniques, and understanding the impacts of LPDV on wild turkey populations.

Characteristics of the white-tailed deer hunting exploitation (Odocoileus virginianus) in Chihuahua, Mexico

Objective: To describe the characteristics of the number of hectares (located in the UMAs registered in the state of Chihuahua) used for the white-tailed deer free-range production, the level of exploitation of the species, and its economic value. Design/Methodology/Approach: This study determined the number of Units for the Conservation, Management, and Sustainable Use of Wildlife (UMAs) registered in the state of Chihuahua, where white tailed deer had been exploited since 2015. Forty-three municipalities in the state of Chihuahua, with a total of 159 UMAs, were analyzed. Twenty-three randomly selected UMAs were characterized, taking into account the hectares and the presence of white-tailed deer per municipality. Finally, the exploitation value of the species use per community was established in order to determine its exploitation and economic value. Results: The total area used for the exploitation of the white-tailed deer reaches 1,067,380 hectares. Thirty-two municipalities had potential for the exploitation of white-tailed deer. Thirty-three deer were hunted per season in the 23 UMAs under study, which accounts for a $990,000 Mexican pesos gross income for the state of Chihuahua per season; this exploitation generates a total of 115 temporary jobs for the communities surrounding the 23 UMAs studied. Chihuahua’s UMAs welcome a total of 33 white-tailed deer hunters per season. Hunters pay $30,000 to $34,000 Mexican pesos for each white-tailed deer specimen. Study Limitations/Implications: The study provides an overview of the current state of the UMAs in the state of Chihuahua that have a permit for the white-tailed deer hunting exploitation. Each of the UMAs under study has specific characteristics, including: the services offered, the associated hunting species, and the exploitation populations under an integrated sustainability arrangement. This study does not include the benefits of exploiting associated species, such as the collared peccary (Dicotyles tajacu) and the wild turkey (Meleagris gallopavo). Findings/Conclusions: Based on the number of registered UMAs, 32 out of 40 municipalities use 100% of their registered area for the exploitation of white-tailed deer. The white-tailed deer hunting exploitation increases the profitability and productivity of livestock ranches.

Detection of lymphoproliferative disease virus in Iowa Wild Turkeys (Meleagris gallopavo): Comparison of two sections of the proviral genome.

An accurate diagnostic test is an essential aspect of successfully monitoring and managing wildlife diseases. Lymphoproliferative Disease Virus (LPDV) is an avian retrovirus that was first identified in domestic turkeys in Europe and was first reported in a Wild Turkey (Meleagris gallopavo) in the United States in 2009. It has since been found to be widely distributed throughout North America. The majority of studies have utilized bone marrow and PCR primers targeting a 413-nucleotide sequence of the gag gene of the provirus to detect infection. While prior studies have evaluated the viability of other tissues for LPDV detection (whole blood, spleen, liver, cloacal swabs) none to date have studied differences in detection rates when utilizing different genomic regions of the provirus. This study examined the effectiveness of another section of the provirus, a 335-nucleotide sequence starting in the U3 region of the LTR (Long Terminal Repeat) and extending into the Matrix of the gag region (henceforth LTR), for detecting LPDV. Bone marrow samples from hunter-harvested Wild Turkeys (n = 925) were tested for LPDV with the gag gene and a subset (n = 417) including both those testing positive and those where LPDV was not detected was re-tested with LTR. The positive percent agreement (PPA) was 97.1% (68 of 70 gag positive samples tested positive with LTR) while the negative percent agreement (NPA) was only 68.0% (236 of 347 gag negative samples tested negative with LTR). Cohen's Kappa (κ = 0.402, Z = 10.26, p<0.0001) and the McNemar test (OR = 55.5, p<0.0001) indicated weak agreement between the two gene regions. We found that in Iowa Wild Turkeys use of the LTR region identified LPDV in many samples in which we failed to detect LPDV using the gag region and that LTR may be more appropriate for LPDV surveillance and monitoring. However, neither region of the provirus resulted in perfect detection and additional work is necessary to determine if LTR is more reliable in other geographic regions where LPDV occurs.

Effect of Thyme Essential Oil on Serum Lipid Profile and Renal Function in Meleagris gallopavo

Effect of Thyme Essential Oil on Serum Lipid Profile and Renal Function in Meleagris gallopavo

Prospecting during egg laying informs incubation recess movements of eastern wild turkeys

BackgroundCentral 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.MethodsUsing 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.ResultsThe 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.ConclusionsOur 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.

Lymphoproliferative Disease Virus and Reticuloendotheliosis Virus Detection and Disease in Wild Turkeys (Meleagris gallopavo).

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.

A validated real-time PCR test for simultaneous detection of Gallus gallus and Meleagris gallopavo in feed instead of an impossible poultry test

Description of the subject. Use of all processed animal proteins (PAPs) in animal feeds was banned in the EU due to the outbreak of bovine spongiform encephalopathy (BSE). This total feed ban was progressively lifted for non-ruminant PAPs from 2013 onwards. Use of ruminant PAPs in feed remains totally prohibited. In order to extend the reintroduction of poultry PAPs in pig feed, and of pig PAPs in poultry feed, as recently decided, poultry species and pig detection tests were required to check that there is no intra-specific recycling. Objectives. In this study, we describe the official EURL-AP real-time PCR method for the simultaneous detection of chicken (Gallus gallus L.) and turkey (Meleagris gallopavo L.), the two most widely used poultry species in PAPs. Method. Classic quality criteria for the validation of a PCR method are considered. A cut-off is required for the interpretation of results. Transferability was tested through an interlaboratory study. Results. The developed PCR assay amplifies an 84 bp fragment encompassing the mitochondrial DNA on 12S ribosomal RNA, tRNA-Val and 16S ribosomal RNA sequences. The qualitative method was successfully assessed for several performance criteria: specificity, sensitivity, efficiency and robustness. The applicability of the test was verified on poultry PAPs and on compound feed containing 0.1% in mass fraction of poultry PAPs. An interlaboratory validation study demonstrated that the proposed real-time PCR method is transferable. Conclusions. The combined chicken-turkey real-time PCR assay is fit for the purpose of detecting poultry PAPs.

Prevalence of parasites in selected captive bird species.

Blood and fecal samples of chukar partridge (Alectoris chukar), albino pheasant (Phasianus colchicus), silver pheasant (Lophura nycthemera), rose-ringed parakeet (Psittacula krameri) and turkeys (Meleagris gallopavo) were analyzed to check parasitic prevalence. To record parasites these five avian species were placed kept in separate cages at Avian Conservation and Research Center, Department of Wildlife an Ecology, University of Veterinary and Animal Sciences, Lahore, Pakistan. 100 fecal and 100 blood samples for each bird species were inspected to analyze internal parasites. During present study, 17 species of endoparasites 14 from fecal samples and three from blood were examined. Two species of ectoparasites i.e. mite Dermanyssus gallinae 42% and fowl ticks Args persicus 41%were studied. Blood parasites included Plasmodium juxtanucleare 50%, Leucoctoyzoon simond having parasitic prevalence 40%, and Aegyptinella pullorum having parasitic prevalence of 40%. Parasitic species recorded from fecal samples included 6 species of nematodes viz. Allodpa suctoria 2%. Syngamus trachea with parasitic prevalence of 60%, Capillaria annulata 37.5%, Ascardia galli 24%, Capillaria anatis 40% and Heterakis gallinarum 28.3%. Similarly, two species of trematodes viz. Prosthogonimus ovatus having parasitic prevalence of 50% and Prosthogonimus macrorchis 21% were also documented from fecal avian samples . Single cestode species Raillietina echinobothrida having parasitic prevalence of 72% and 3 protozoan species i.e. Eimeria maxima having parasitic prevalence of 21%, Giardia lamblia 41% and Histomonas meleagridis 18% were documented during corpological analysis. In our recommendation, proper sanitation, medication and vaccination of bird's enclousres are suggested to avoid parasites.

Pathological Characterization of Cryptosporidiosis in Naturally Infected Hybrid Converter Breeds of Meleagris Gallopavo

Pathological Characterization of Cryptosporidiosis in Naturally Infected Hybrid Converter Breeds of Meleagris Gallopavo

Liquid semen storage-induced alteration in the protein composition of turkey (Meleagris gallopavo) spermatozoa

Liquid storage of turkey semen without the loss of fertilizing ability is of practical interest to the poultry industry. However, fertility rates from liquid-stored turkey semen decline within a few hours. A clear cause of the decline in spermatozoa quality remains unidentified. Therefore, the purpose of the present study was to monitor the dynamics of proteomic changes in spermatozoa during 48 h of liquid storage by 2-dimensional difference in-gel electrophoresis coupled with matrix-assisted laser desorption/ionization mass spectrometry. A total of 57 protein spots were differentially expressed between fresh and stored spermatozoa; 42 spots were more and 15 were less abundant after 48 h of semen storage. Raw proteomic data are available via ProteomeXchange with identifier PXD043050. The selected differentially expressed proteins (DEPs) were validated by western blotting and localized in specific spermatozoa structures by immunofluorescence, such as the head (acrosin and tubulin α), midpiece (acrosin, aconitate hydratase 2, and glycerol-3-phosphate dehydrogenase) and tail (tubulin α). Most of the DEPs that changed in response to liquid storage were related to flagellum-dependent cell motility, energy derivation through oxidation of organic compounds and induction of fertilization, suggesting the complexity of the processes leading to the decrease in stored semen quality. The damaging effect of liquid storage on spermatozoa flagellum manifested as more microtubule proteins, such as tubulins and tektins, most likely formed by posttranslational modifications, tubulin α relocation from the tail to the sperm head, which appeared after 48 h of semen storage, and decreases in fibrous shelf proteins at the same time. Motility could be affected by dysregulation of Ca2+-binding proteins and disturbances in energy metabolism in spermatozoa flagellum. Regarding sperm mitochondria, DEPs involved in energy derivation through the oxidation of organic compounds indicated disturbances in fatty acid beta oxidation and the tricarboxylic acid cycle as possible reasons for energy deficiency during liquid storage. Disturbances in acrosin and 1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase zeta may be involved in rapid declines in the fertility potential of stored turkey spermatozoa. These results showed the complexity of the processes leading to a decrease in stored semen quality and broadened knowledge of the detrimental effects of liquid storage on turkey spermatozoa physiology.

Canopy reduction and fire seasonality effects on deer and turkey habitat in upland hardwoods

Understory conditions strongly influence the value of upland hardwood forests for white-tailed deer (Odocoileus virginianus) and wild turkey (Meleagris gallopavo). Canopy reduction can be paired with low-intensity prescribed fire to increase forage and cover. Most fire in these systems is applied during the dormant season, but there may be benefits to burning during different seasons to provide different resources throughout the year. We implemented a shelterwood harvest with reserves in four upland hardwood stands in east Tennessee in 2010, then applied fire during the early-growing season (EGS) and late-growing season (LGS) to different treatment units on approximately a 2.2-year return interval from 2012–2023. We recorded vegetation composition, measured vegetation structure, calculated deer forage availability, and tallied wildlife detections via camera traps in summer 2023 to evaluate our treatments relative to an unharvested and unburned control. We found canopy reduction and fire during either season resulted in greater understory coverage of plants, with tree and bramble coverage greatest following LGS fire, which was lower intensity on average than EGS fire. Vegetation structure following EGS fire was more open, which is typically selected by brooding turkeys. The taller structure following LGS fire provided conditions typically selected for bedding or fawning by deer and nesting for turkeys. Deer forage biomass in July was increased by both EGS and LGS relative to control, but forage of sufficient quality to support a lactating doe was increased only in EGS because of increased nutrition of recently resprouting vegetation. Deer and turkey detections were greater in EGS than control or LGS during May–June. Turkey detections remained greater in EGS during July–August, but deer use was similar between EGS and LGS during July–August. Our results indicate burning during different seasons following canopy reduction can promote different food and cover resources which are important for deer and turkeys during different times of the year.

Isolation of Toxoplasma gondii in cell culture: an alternative to bioassay

Toxoplasma gondii is an apicomplexan protozoan parasite that can infect mammals and birds. The infection can cause acute toxoplasmosis and death in susceptible hosts. Bioassay using cats and mice has been the standard for the isolation of T. gondii from infected hosts for the past several decades. However, bioassay is labor-intensive, expensive, and involves using laboratory animals. To search alternative approaches and o work towards replacement of animal experiments, we summarized the key literature and conducted four experiments to isolate T. gondii in vitro by cell culture. A few heart tissue samples from animals with the highest antibody titers in a given collection were used for T. gondii isolation. These experiments included samples from five out of 51 wild ducks, four of 46 wild turkeys, six of 24 white-tailed deer, as well as from six kangaroos that had died with acute toxoplasmosis in a zoo. These experiments resulted in three isolates from five chronically infected wild ducks (60%), four isolates from four chronically infected wild turkeys (100%), one isolate from six chronically infected white-tailed deer (17%), and four isolates from six kangaroos with acute toxoplasmosis (67%). In addition, five isolates from the five chronically infected wild ducks were obtained by bioassay in mice, showing a 100% success rate, which is higher than the 60% rate by direct cell culture. These T. gondii isolates were successfully propagated in human foreskin fibroblast (HFF) or Vero cells, and genotyped by multilocus PCR-RFLP markers. The results showed that it is practical to isolate T. gondii directly in cell culture. Although the cell culture approach may not be as sensitive as the bioassay, it does provide an alternative that is simple, cost-effective, ethically more acceptable, and less time-sensitive to isolate T. gondii. In this paper we propose a procedure that may be applied and further optimized for isolation of T. gondii.

Survival and cause‐specific mortality of male wild turkeys across the southeastern United States

AbstractEstimating survival and cause‐specific mortality of male eastern wild turkeys (Meleagris gallopavo silvestris) is important for understanding population dynamics and implementing appropriate harvest management. To better understand age‐specific estimates of annual survival and harvest rates, we captured and marked male wild turkeys with leg bands (n = 311) or bands and transmitters (n = 549) in Georgia, Louisiana, North Carolina, and South Carolina, USA, during 2014–2022. We fitted time to event models to data from radio‐marked birds to estimate cause‐specific mortality and annual survival. We used band recovery models incorporating both band recovery and telemetry data to further investigate harvest rates and survival. Annual survival from known‐fate models in hunted populations was 0.54 (95% CI = 0.49–0.59) for adults and 0.86 (95% CI = 0.81–0.92) for juveniles. Cause‐specific mortality analysis produced an annual harvest estimate of 0.29 (95% CI = 0.24–0.33) for adults and 0.02 (95% CI = 0.01–0.03) for juveniles, whereas predation was 0.15 (95% CI = 0.10–0.20) and 0.12 (95% CI = 0.08–0.17), respectively. Annual survival for adult males in a non‐hunted population was 0.83 (95% CI = 0.72–0.97). Survival rate was negatively correlated with harvest rate, indicating harvest was an additive mortality source. Annual survival from band recovery models was 0.40 (95% CI = 0.37–0.44) for adults and 0.88 (95% CI = 0.81– 0.93) for juveniles, whereas annual harvest estimates were 0.24 (95% CI = 0.23–0.25) for adults and 0.04 (95% CI = 0.03–0.05) for juveniles. Both models suggested no differences in annual survival across years or among study areas, which included privately owned and public properties. Harvest was an additive mortality source for male wild turkeys, suggesting that managers interested in increasing annual survival of adult males could consider ways of reducing harvest rates.