Infectious disease survey of Rio Grande wild turkeys in the Edwards Plateau of Texas

State wildlife agencies have translocated thousands of wild turkeys (Meleagris gallopavo) since the 1930s to reestablish this species. Because of threats to the domestic poultry industry and wild birds, screening for selected infectious agents has become routine since the early 1980s. One of the principal sources for Rio Grande wild turkeys (M. gallopavo intermedia) for translocation purposes was the Edwards Plateau of Texas (USA). Unfortunately, turkey abundance has declined in the southern Edwards Plateau since the late 1970s. Surprisingly few studies have addressed wild turkeys in this region, perhaps reflecting its status as the heart of Rio Grande turkey range. We surveyed 70 free-living Rio Grande wild turkeys from Bandera and Kerr counties, Texas, for evidence of exposure to Salmonella typhimurium, S. pullorum, Mycoplasma gallisepticum, M. meleagridis, M. synoviae, Chlamydophila psittaci, and the avian influenza, Newcastle disease, turkey corona, and reticuloendotheliosis viruses. Of these, 80% (56) were seropositive for both M. gallisepticum and M. synoviae on the serum plate antigen test. Ten of these individuals (14% of total) were positive for M. synoviae by hemagglutination inhibition testing. All other serologic tests were negative. Two adult females sampled in Kerr County, whose body mass was significantly less than that of other adult females trapped in the area, tested positive for reticuloendotheliosis virus (REV) proviral DNA on polymerase chain reaction. Reticuloendotheliosis virus was isolated from one of these individuals. The pathogenesis, transmission, and/or population-level influences of M. gallisepticum, M. synoviae, and REV in Rio Grande wild turkeys deserves further study.     

A finding of Blastocystis galli (Rhizopoda, Lobosea) in domestic turkeys]

Blastocysts tentatively assigned to the species Blastocystis galli were found in the turkey Meleagris gallopavo from Tajikistan and Uzbekistan. Length and width of blastocysts from turkeys vary in a wider range (2.5--55.1 x 2.5--51.3 mkm) than length and width of blastocysts from hens. The shape of blastocysts varies from round and oval to ellipsoid and amoeboid.     

Absence of avian pox in wild turkeys in central Mississippi.

Eastern wild turkeys (Meleagris gallopavo silvestris) (n = 1,023), obtained during winter, spring, and summer from 1983 to 1988 on Tallahala Wildlife Management Area (TWMA) (Jasper County, Mississippi, USA) were examined for avian pox lesions. Domestic turkey poults (n = 152) maintained on the area for 1 to 2 wk periods from 1987 to 1989 also were examined. Neither wild nor domestic birds showed gross evidence of pox virus infection. This study indicated that avian pox was not endemic in wild turkeys at TWMA.     

An investigation of the persistence of Mycoplasma gallisepticum in an Eastern population of wild turkeys

Mycoplasma gallisepticum infection had been confirmed by culture and serology among wild turkeys (Meleagris gallopavo) in close association with domestic fowl on Cumberland Island, Georgia (USA) in 1980. In 1988, wild turkeys were surveyed by serologic and cultural methods for evidence of M. gallisepticum. Chickens (Gallus gallus) and guinea fowl (Numida meleagris) from the site where the disease was originally detected also were tested by serologic and cultural methods for M. gallisepticum infections. There was no conclusive evidence that M. gallisepticum was present in wild turkeys or guinea fowl. In contrast, most chickens were strongly seropositive for M. gallisepticum, suggesting that they had been infected, although the organism was not recovered by cultural or bioassay methods. Other species of Mycoplasma isolated were M. gallopavonis from wild turkeys, M. gallinaceum and M. pullorum from chickens, and M. gallinaceum from guinea fowl. It appears that M. gallisepticum has not persisted or spread in the wild turkey population on Cumberland Island, despite continued contact by some wild turkeys with suspected carrier chickens.     

Mosquito transmission of wild turkey malaria, Plasmodium hermani.

Culex nigripalpus experimentally transmitted Plasmodium hermani, a plasmodium of wild turkeys (Meleagris gallopavo) in Florida. The mosquitoes were infected by feeding upon blood induced parasitemias in domestic turkey poults. The resulting sporozoites, transmitted by either mosquito bites or injection, produced malaria infections in domestic poults.     

Prevalence of Bordetella avium infection in selected wild and domesticated birds in the eastern USA

Bordetella avium is the etiologic agent of bordetellosis, a highly contagious upper respiratory disease of young poultry. Its prevalence among domesticated turkeys is well-known, but information on prevalence of this bacterium in other birds is limited. A survey of the prevalence of B. avium in wild and domesticated birds was conducted from June 1998 to January 2000, using tracheal cultures and serology. Of 237 blood samples from 61 species, 100 individuals from 41 species had antibodies against B. avium as determined with a microtiter agglutination test. Nine isolates of B. avium were cultured from 128 tracheal samples. Ribotype analysis of seven isolates from mallards (Anas platyrhynchos), one from a wild turkey (Meleagris gallopavo), and one from a Canada goose (Branta canadensis) indicated that they represent three strains, two of which were indistinguishable from clinical isolates from domesticated turkeys. Bordetella avium is present in wild bird populations of multiple species. Transmission from free-living avian populations to domesticated poultry populations may be possible and should be examined.     

Isolation and characterization of microsatellite loci in wild and domestic turkeys (Meleagris gallopavo)

We describe the isolation, development and application of seven microsatellite loci in the eastern wild turkey, Meleagris gallopavo silvestris, as well as their amplification and levels of polymorphism in the domestic turkey. The number of alleles per locus ranged from 5 to 15 and average heterozygosity was high for almost all loci. Domestic turkeys showed significantly reduced numbers of alleles per locus and overall heterozygosities when compared to eastern wild turkeys. The high variability in these markers should provide the level of resolution required to continue studies of wild turkey population genetics.     

Serological and microbial survey of Mycoplasma gallisepticum in wild turkeys (Meleagris gallopavo) from six western states.

From 1986 to 1989, sera from wild turkeys (Meleagris gallopavo), including three subspecies (M. gallopavo intermedia, M. gallopavo merriami and M. gallopavo mexicana) trapped in six western states were tested for antibody to Mycoplasma gallisepticum (MG) (n = 724), M. synoviae (MS) (n = 461) and M. meleagridis (MM) (n = 354) using the rapid plate agglutination (RPA) assay. Subsamples of these sera were also evaluated using the hemagglutination inhibition (HI) assay for antibody to MG (n = 664) and MS (n = 403). Attempts were made to isolate mycoplasmas by swabbing the trachea and cloaca of 190 live wild turkeys and from various tissues (sinus, nasal turbinates, trachea, lung, ovaries and oviduct) from 76 turkeys at necropsy. Isolates were identified using an immunobinding assay. Seroprevalence of MG, MS and MM in the RPA test was highly variable among years and geographic sites, ranging from 0 to 85%, 0 to 87%, and 0 to 83%, respectively, for each mycoplasma species. Of the 724 wild turkey sera tested, 200 (28%) were positive using the RPA assay, while only 20 (3%) of 664 sera tested using the HI assay were positive (at a titer greater than/= 1:80) for antibody to MG. Of the 461 sera tested 178 (39%) were RPA positive for MS, whereas none of the 403 samples tested by HI were positive for MS. Antibody to MM was detected in 72 (20%) of 354 turkey sera tested by RPA. Mycoplasmas were cultured from 81 (30%) of 266 wild turkeys, including 48 that were sampled live and 33 that were examined by necropsy. Mycoplasmas were isolated from every population in which culture was attempted. M. gallopavonis (MGP) was isolated from 37 (46%) of 81 birds which yielded mycoplasma, representing seven of 12 populations sampled. MG was isolated from lower respiratory tissues of one Rio Grande wild turkey trapped in Texas. M. synoviae was isolated from five of 16 Merriam's wild turkeys trapped in Arizona. Sera of birds from which MG or MS was isolated were positive to the respective antigen in the RPA test, but were negative by the HI assay. The RPA test was effective in identifying MG and MS infected turkeys despite lack of confirmation by the HI test. These data suggest that apparently healthy wild turkeys can carry pathogenic mycoplasmas and the currently used field test (RPA) can identify culture positive wild turkeys. Serological screening using the RPA test should be conducted on all wild turkeys prior to relocation.     

Microsatellite loci for genetic mapping in the turkey (Meleagris gallopavo)

New microsatellite loci for the turkey (Meleagris gallopavo) were developed from two small insert DNA libraries. Polymorphism at these new loci was examined in domestic birds and two resource populations designed for genetic linkage mapping. The majority of loci (152 of 168) was polymorphic in domestic turkeys and informative in two mapping resource populations and thus will be useful for genetic linkage mapping.     

FHF-2 in the turkey (Meleagris gallopavo)

A cDNA clone homologous to the fibroblast growth factor homologous factor (FHF-2) was isolated and sequenced from the turkey (Meleagris gallopavo). The DNA sequence of the turkey was almost identical to that of the chicken (99% similarity) differing at only 8 of 770 nucleotides in the coding region resulting in a single amino acid difference between these poultry species. The 3'UTR of the turkey FHF-2 gene was 445 nucleotides in length and included an imperfect CT microsatellite (ms) repeat. The sequence of the 3'UTR was amplified from genomic DNA of the chicken and found to be highly conserved differing at only three nucleotides when compared to the turkey. Length of the CT repeat was indifferent in a sample of 52 turkeys (monomorphic) however, the number of CT repeats was greater in the turkey than in the chicken. No inter-individual polymorphism was detected in multiple sequences of the 3'UTR of the FHF-2 gene in the turkey. Based on comparison of the turkey and chicken sequences, the mutation rate for coding and associated non-coding (3'UTR) regions of FHF-2 are approximately equal.     

Whole genome SNP discovery and analysis of genetic diversity in Turkey (Meleagris gallopavo)

ABSTRACT: BACKGROUND: The turkey (Meleagris gallopavo) is an important agricultural species and the second largest contributor to the world's poultry meat production. Genetic improvement is attributed largely to selective breeding programs that rely on highly heritable phenotypic traits, such as body size and breast muscle development. Commercial breeding with small effective population sizes and epistasis can result in loss of genetic diversity, which in turn can lead to reduced individual fitness and reduced response to selection. The presence of genomic diversity in domestic livestock species therefore, is of great importance and a prerequisite for rapid and accurate genetic improvement of selected breeds in various environments, as well as to facilitate rapid adaptation to potential changes in breeding goals. Genomic selection requires a large number of genetic markers such as e.g. single nucleotide polymorphisms (SNPs) the most abundant source of genetic variation within the genome. RESULTS: Alignment of next generation sequencing data of 32 individual turkeys from different populations was used for the discovery of 5.49 million SNPs, which subsequently were used for the analysis of genetic diversity among the different populations. All of the commercial lines branched from a single node relative to the heritage varieties and the South Mexican turkey population. Heterozygosity of all individuals from the different turkey populations ranged from 0.17-2.73 SNPs/Kb, while heterozygosity of populations ranged from 0.73-1.64 SNPs/Kb. The average frequency of heterozygous SNPs in individual turkeys was 1.07 SNPs/Kb. Five genomic regions with very low nucleotide variation were identified in domestic turkeys that showed state of fixation towards alleles different than wild alleles. CONCLUSION: The turkey genome is much less diverse with a relatively low frequency of heterozygous SNPs as compared to other livestock species like chicken and pig. The whole genome SNP discovery study in turkey resulted in the detection of 5.49 million putative SNPs compared to the reference genome. All commercial lines appear to share a common origin. Presence of different alleles/haplotypes in the SM population highlights that specific haplotypes have been selected in the modern domesticated turkey.     

Ground Roost Resource Selection for Merriam's Wild Turkeys

ABSTRACT Concealment cover is important for ground-roosting wild turkey (Meleagris gallopavo) poults immediately following hatch during the vulnerable, preflight stage. We compared concealment cover resources selected at ground roosts to those of nest sites and available resources for Merriam's turkeys (Meleagris gallopavo merriami) in the Black Hills of South Dakota, USA. Females with preflight poults selected ground roosts that were similar in structure to nest sites. Ground roosts and nests were greater in visual obstruction (unit odds ratios ≥1.19) than random sites. However, ground roosts were closer to meadow-forest edges than either nests or random sites (unit odds ratios ≤0.98). Structure at ground roosts may provide visual protection from predators, and management for shrub vegetation or woody debris along meadow-pine forest ecotones will provide cover for Merriam's turkey broods.     

Plasmodium durae Herman from the introduced common peafowl in northern Nigeria

Plasmodium (Giovannolaia) durae Herman was originally described from Kenya, the type host being the common turkey, Meleagris gallopavo Linnaeus. There are no field records of this association outside of Africa, where the parasite, herein reported from another introduced and domesticated bird (the common peafowl, Pavo cristatus Linnaeus), was recently listed from 2 native Phasianidae of the genus Francolinus. The justification for the present identification is submitted against background data concerning malaria parasites from turkeys and other Galliformes in Africa and elsewhere, and restraint is urged in describing yet more "new species" of avian Plasmodium belonging to morphologically close taxa within Novyella and Giovannolaia. A near relative of P. durae, Plasmodium dissanaikei de Jong, is transferred from the former subgenus to the latter one.     

Gobbling across landscapes: Eastern wild turkey distribution and occupancy–habitat associations

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.     

Genetic Variation at the MHC in a Population of Introduced Wild Turkeys

Genetic variation in the major histocompatibility complex (MHC) is known to affect disease resistance in many species. Investigations of MHC diversity in populations of wild species have focused on the antigen presenting class IIβ molecules due to the known polymorphic nature of these genes and the role these molecules play in pathogen recognition. Studies of MHC haplotype variation in the turkey (Meleagris gallopavo) are limited. This study was designed to examine MHC diversity in a group of Eastern wild turkeys (Meleagris gallopavo silvestris) collected during population expansion following reintroduction of the species in southern Wisconsin, USA. Southern blotting with BG and class IIβ probes and single nucleotide polymorphism (SNP) genotyping was used to measure MHC variation. SNP analysis focused on single copy MHC genes flanking the highly polymorphic class IIβ genes. Southern blotting identified 27 class IIβ phenotypes, whereas SNP analysis identified 13 SNP haplotypes occurring in 28 combined genotypes. Results show that genetic diversity estimates based on RFLP (Southern blot) analysis underestimate the level of variation detected by SNP analysis. Sequence analysis of the mitochondrial D-loop identified 7 mitochondrial haplotypes (mitotypes) in the sampled birds. Results show that wild turkeys located in southern Wisconsin have a genetically diverse MHC and originate from several maternal lineages.     

Plasmodium durae Herman from the Introduced Common Peafowl in Northern Nigeria

SYNOPSIS. Plasmodium ( Giovannolaia ) durae Herman was originally described from Kenya, the type host being the common turkey, Meleagris gallopavo Linnaeus. There are no field records of this association outside of Africa, where the parasite, herein reported from another introduced and domesticated bird (the common peafowl, Pavo cristatus Linnaeus), was recently listed from 2 native Phasianidae of the genus Francolinus. The justification for the present identification is submitted against background data concerning malaria parasites from turkeys and other Galliformes in Africa and elsewhere, and restraint is urged in describing yet more "new species" of avian Plasmodium belonging to morphologically close taxa within Novyella and Giovannolaia. A near relative of P. durae, Plasmodium dissanaikei de Jong, is transferred from the former subgenus to the latter one.     

Hematozoa of wild turkeys from the midwestern United States: translocation of wild turkeys and its potential role in the introduction of Plasmodium kempi

Twenty-three of 310 blood samples taken from live-trapped eastern wild turkeys (Meleagris gallopavo silvestris) from Missouri (USA), and hunter-killed birds from Wisconsin, North Dakota and Minnesota (USA), and inoculated into domestic broad-breasted-white turkey poults were positive for two species of Plasmodium. Twenty-one of the positive samples were infected with P. (Novyella) kempi, and two samples from Wisconsin were infected with P. (Giovannolaia) lophurae. Twenty percent of 310 blood smears were positive for Haemoproteus melagridis, while only 3% were infected with Leucocytozoon smithi. A statistically higher prevalence of Plasmodium spp. from 1983 to 1984 was observed in Wisconsin, and in the samples from Minnesota when compared with both Missouri and Wisconsin. Turkeys from Wisconsin and Minnesota had both a statistically higher prevalence and mean intensity of H. meleagridis than birds from Missouri. Evidence indicates that P. kempi has been introduced into other states along with the vertebrate hosts. It is suggested that greater care should be exercised when translocated wild turkeys are introduced into areas where there are other endangered or threatened avian species.     

Biliary bile acid profiles of domestic fowl as determined by high performance liquid chromatography and fast atom bombardment mass spectrometry

1. The biliary bile acid profiles of domestic chickens (Gallus domesticus), turkeys (Meleagris gallopavo), and ducks (Anas platyrhynchos) were determined by high performance liquid chromatography (HPLC) and fast atom bombardment mass spectrometry (FAB-MS). 2. Chenodeoxycholyltaurine and cholyltaurine were the predominant bile acids in chicken and turkey bile, whereas duck bile contained primarily chenodeoxycholyltaurine and phocaecholyltaurine. 3. Allocholyltaurine was also detected in chicken and turkey bile, but not in duck bile. 4. FAB-MS analyses of individual HPLC peak fractions from chicken and duck bile extracts confirmed the presence of either taurine-conjugated dihydroxy- or trihydroxycholanoates. 5. Direct FAB-MS analyses of avian bile extracts not subjected to HPLC permitted a rapid assessment of the relative proportion of taurine-conjugated dihydroxy- to trihydroxycholanoates.     

Intoxication of nontarget wildlife with rodenticides in northwestern Kansas

The perception of prairie dogs (Cynomys spp.) both as a nuisance species and a keystone species presents a significant challenge to land, livestock, and wildlife managers. Anticoagulant and nonanticoagulant rodenticides are commonly employed to control prairie dog populations throughout their range. Chlorophacinone, and to a lesser extent zinc phosphide, are widely used in northwestern Kansas for controlling black-tailed prairie dog (Cynomys ludovicianus) populations. Although zinc phosphide poisoning of gallinaceous birds is not uncommon, there are few published accounts of nontarget chlorophacinone poisoning of wildlife. We report three mortality events involving nontarget rodenticide poisoning in several species, including wild turkeys (Meleagris gallopavo), a raccoon (Procyon lotor), and an American badger (Taxidea taxus). This includes the first documentation of chlorophacinone intoxication in wild turkeys and an American badger in the literature. The extent of nontarget poisoning in this area is currently unknown and warrants further investigation.     

Mycoplasma gallopavonis in eastern wild turkeys.

Serum samples and tracheal cultures were collected from eastern wild turkeys (Meleagris gallopavo sylvestris) trapped for relocation in South Carolina (USA) during 1985 to 1990. Sera were tested for Mycoplasma gallisepticum and M. synoviae by the rapid plate agglutination and hemagglutination inhibition tests and were found to be negative. Tracheal cultures were negative for all pathogenic Mycoplasma spp., including M. gallisepticum, M. synoviae, M. meleagridis, and M. iowae. However, M. gallopavonis was isolated from every group of wild turkeys tested in 1986 to 1990. These data suggest that M. gallopavonis, which is generally considered nonpathogenic, may be a common microorganism in eastern wild turkeys.