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L L Vaccagalloway - One of the best experts on this subject based on the ideXlab platform.
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changes in receptor levels for thyrotropin releasing hormone serotonin and substance p in cervical spinal cord of wobbler mouse a quantitative autoradiography study during early and late stages of the motoneuron disease
Brain Research, 1996Co-Authors: Y P Deng, S H Zhang, L L VaccagallowayAbstract:Receptor levels for thyrotropin releasing hormone (TRH) measured by quantitative autoradiography in the Wobbler mouse cervical spinal cord show receptor losses that may relate to the inherited loss of motoneurons, most pronounced late (at Stage 4) in the motoneuron disease. An age-related decrease of TRH and serotonin (5-HT) receptors can be seen in the ventral horn of the control specimens (normal phenotype littermate and wild-type alike). However, this pattern is missing for substance P (SP) receptors from the wild-type specimens. Therefore the age-related decrease of SP receptors detected in the Wobbler mouse strain may identify a strain-related defect in SP neuronal/receptor developmental patterns. A higher level of TRH receptors was measured in the Wobbler dorsal horn at an early stage (Stage 1) in the motoneuron disease compared with the control specimens. The data are discussed in relation to an aberrant neuronal sprouting that occurs around the degenerating motoneurons in the ventral horn during the course of the motoneuron disease.
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alterations in acetylcholinesterase and choline acetyltransferase activities and neuropeptide levels in the ventral spinal cord of the wobbler mouse during inherited motoneuron disease
Brain Research, 1994Co-Authors: K K L Yung, F Tang, L L VaccagallowayAbstract:Abstract Enymatic assays for acetylcholine esterase (AChE) and choline acetyltransferase (ChAT) were applied to dorsal and ventral cervical spinal cord regions taken from the Wobbler mouse, a model for inherited motoneuron disease. Early in the disease, ChAT (but not AChE) activity is significantly greater compared with the control littermate specimens. The high ChAT activity correlates with the high thyrotopin releasing hormone (also leucine-enkephalin) concentrations measured in the Wobbler ventral horn early in the disease. Late in the motoneuron disease, both AChE and ChAT activities are significantly lower than in the control littermate spicemens. These data correlate with the high substance P, methionine and leucine enkephalin concentrations measured in the Wobbler ventral horn late in the motoneuron disease.
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alteration in the levels of thyrotropin releasing hormone substance p and enkephalins in the spinal cord brainstem hypothalamus and midbrain of the wobbler mouse at different stages of the motoneuron disease
Neuroscience, 1992Co-Authors: K K L Yung, F Tang, R Fielding, L L VaccagallowayAbstract:The present study was undertaken to quantify selected neuropeptides (thyrotropin releasing hormone, substance P, methionine and leucine enkephalin) in the cervical spinal cord and other regions of the central nervous system of Wobbler mice by radioimmunoassays during several stages of the motoneuron disease compared with age- and sex-matched normal phenotype littermates. In Wobbler spinal cord, thyrotropin releasing hormone is higher early in the disease, whereas in the brainstem it is higher at a later stage. Substance P in spinal cord is also higher late in the disease. Leucine enkephalin levels are greater at all stages in diseased spinal cord and brainstem, but methionine enkephalin increases only late in the disease. Highly significant increases of the peptides (except thyrotropin releasing hormone) appear in hypothalamus and midbrain only late in the motoneuron disease. Regression analyses show that thyrotropin releasing hormone in spinal cord and brainstem decreases normally with age in the control mice and at a faster rate related to the extent of motor impairment in Wobbler mice. Thyrotropin releasing hormone and methionine enkephalin in the Wobbler brainstem correlate (P < 0.05) with the progress of the motoneuron disease. Methionine enkephalin increases faster in Wobbler brainstem and decreases faster in control spinal cord with age. The increase of leucine enkephlin in the Wobbler spinal cord correlates significantly with age and with the progress of the disease, but leucine enkephalin declines slightly with age in the controls. The changes of substance P in spinal cord and brainstem do not correlate significantly with the progress of the disease. In the hypothalamus, increasing values for substance P in control specimens and enkephalins in Wobbler specimens are significantly correlated with age. However, in the midbrain, higher methionine and leucine enkephalin levels are significantly associated with age only in the control mice. Alterations of neuropeptides in the Wobbler mouse spinal cord and brainstem may result from the degeneration of bulbospinal raphe neurons projecting to the ventral spinal cord, or from primary afferent or interneuronal nerve terminals. The data imply that the neuronal degeneration process in the Wobbler motoneuron disease is not limited to motoneurons. In the spinal cord, the data support our previous hypothesis that neuronal sprouting presynaptic to the motoneurons may account for increased neuropeptide concentrations. Alternatively, synthesis and/or degradation of these peptides may be altered. In addition, it is proposed that enkephalinergic neurons may develop abnormally in Wobbler mice. The early increase of leucine enkephalin in the Wobbler spinal cord possibly indicates its importance in the etiology of the motoneuron disease.
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spiny interneurons identified in the normal mouse spinal cord show alterations in the wobbler mouse a model for inherited motoneuron disease
Restorative Neurology and Neuroscience, 1992Co-Authors: L L VaccagallowayAbstract:Presumed interneurons are described in the Golgi-impregnated cervical spinal cord taken from normal phenotype and motoneuron-diseased mice of the Wobbler mouse strain (NFR/wr), as well as from the spinal cord of two related normal mouse strains (C57B1/6N and NFR/N). The interneurons, distributed throughout Rexed's laminae V-VIII, are characterized by numerous spines clustered along the distal dendrites. Quantitatively, the soma size (μm2) of the interneurons in the Wobbler specimens studied late in the motoneuron disease is smaller than that measured in the pair-matched (3-week-old) normal phenotype littermates. Early in the disease, the spine density (number of spines per 100 μm length dendrite) is greater compared with the normal phenotype littermates, perhaps implying that sprouting may occur. At a later stage in the disease process, the spine density does not differ significantly. However the increase in the spine density expected with advancing age is not observed for the Wobbler interneurons. It is proposed that perhaps the normal age-related proliferation of spines is impaired in the Wobbler mice. Since the measurements for spine length are lower in the Wobbler interneurons studied late in the motoneuron disease compared with the pair-matched (3-month-old) normal phenotype littermates, the normal age-related lengthening of the spines seems to be lacking. In addition, the spine length measured in the normal phenotype littermates is significantly greater compared with the normal mice (NFR/N, C57B1/6N). Thus the growth patterns of the spines may differ in the Wobbler mouse strain compared with the normal (C57B1/6N, NFR/N) mouse strains. It is proposed that the Wobbler motoneuron disease affects interneurons as well as motoneurons.
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reduced branching and length of dendrites detected in cervical spinal cord motoneurons of wobbler mouse a model for inherited motoneuron disease
The Journal of Comparative Neurology, 1991Co-Authors: L L VaccagallowayAbstract:The Wobbler mouse (wr) has been proposed as a model for human inherited motoneuron disease (infantile spinal muscular atrophy). The primary defect is thought to be in the motoneurons. Therefore we undertook a survey of the qualitative and quantitative changes occurring in the cervical spinal motoneurons of Wobbler mice during a late stage of the motoneuron disease compared with age- and sex-matched normal phenotype (NFR/wr) littermates. The Rapid Golgi Method was applied. In control and Wobbler mice, four types of neurons were identified according to their dendritic patterns: multipolar, tripolar, bipolar, and unipolar cells. Unipolar cells were observed more often in the Wobbler specimens than the controls and may represent a final stage in the degeneration of other cell types with greater numbers of primary dendrites. Medium (300-999 microns 2) and large (greater than 1,000 microns 2) impregnated neurons (presumably alpha-motoneurons) showed strong indications of cell degeneration, including statistically significant reductions in the measurements for dendritic length, distribution, and branching, as well as the number of spines. In contrast, the small (less than 300 microns 2) neurons showed only mild signs of degeneration, including slight reductions in dendritic length, but no significant differences appeared in the distribution and branching of dendrites, or in the number of spines. Instead, a small increase could be detected in the number of primary and secondary dendritic branches emanating from the small neurons, as well as in the number of dendritic spines. These findings suggest that sprouting may occur to a slight extent. Although previous studies document that swelling with subsequent vacuolation of motoneurons is the predominant feature characterizing the Wobbler disease, the mean soma area (microns 2) calculated for the impregnated neurons of the Wobbler specimens showed no significant difference from the controls. It is hypothesized that the advanced signs of the Wobbler motoneuron disease are primarily reflected in the degeneration of the dendrites and spines on the medium and large alpha-motoneurons. The small neurons (presumably a mixed population of gamma-motoneurons, interneurons, and Renshaw cells) possess dendrites and spines that seem to be less affected, and instead show signs of sprouting.
Bruce D. Leopold - One of the best experts on this subject based on the ideXlab platform.
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RELATIONSHIPS BETWEEN WILD TURKEYS AND RACCOONS IN CENTRAL MISSISSIPPI
2007Co-Authors: Charles D. Lovell, Darren A. Miller, George A. Hurst, Bruce D. LeopoldAbstract:Reduced trapping and hunting of predators has led to concerns that increased predator densities may aged game species populations. Therefore, we investigated effects of predation on the wild turkey population on Tallahala Wildlife Management Area (TWMA), Mississippi, from 1984-94. We also determined trends in raccoon trapping and hunter harvest in Mississippi. Predation of nests (eggs), nesting hens, and points caused a population decline on TWMA. Most (88°!0) nest failures were caused by predation from 1984-94; raccoons were the dominant predator. Declining raccoon hunter harvest from 1980-94 was correlated with declining hunter effort. Trapping license sales and trapping harvest also declined. On TWMA, declining hunter effort was correlated with declining raccoon harvest, reflecting the statewide trend. Further reduction of predator harvest, particularly of raccoons, may negatively impact wild turkey populations in Mississippi. Future research should investigate wild turkey/predator dynamics, effects of natural controls (e.g., disease) on predator densities, and possible trapping incentives to reduce predator densities. Proc, East. Wildl. Damage Mint. Conf 7:118-129. 1997. Declines in harvest of predators has led to their increase in most areas of North America (Hamilton and Vangilder 1992). Predation of endangered species [e.g., Mississippi sandhill crane (Gras canadensis ulla , whooping cranes (G. americana , piping plover (Charadrius melodus ] and game species (e.g., gamebirds, ungulates, and waterfowl) has increased as predator populations have increased and habitats have decreased (Hamilton and Vangilder 1992). Therefore, some management strategies have shifted to predator control. Many researchers reported that predator control was not economically nor biologically . feasible in the long term (MacDonald and Jantzen 1967, Knowlton 1972, Beasom 1974b, Trautman et al. 1974, Connolly and Longhurst 1975, Guthery and Beasom 1977). However, other studies reported positive responses to predator control by gamebird Ligon 1946, Beasom 1974a, Pons 1986, Tapper et al. 1991) and waterfowl populations (Baker et al. 1968, Duebbert and Lokemoen 1980, Greenwood et al. 1990, Hamilton and Vangilder 1992). Predators have been found to be a limiting factor for eastern wild turkey Melee 's gallopavo silvestris populations (5peake 1980, Hamilton and Vangilder 1992, Miller and Leopold 1992). Primary nest predators in the Southeast include raccoons Pr on lotor , opossums Di el his vir ' 'ana , and striped skunks s (Mephitis mephitis Predators which prey on adult turkeys are coyotes (Canis latrans , bobcats ells rufus), gray r on cinereoar eg teas) and red foxes ul es vul es , feral dogs (C_. familiaris , and great-horned owls (Bubo Virginianus Predation of eggs and incubating hens during the nesting season limits the wild turkey population on Tallahala Wildlife Management Area (TWMA) (Palmer et al. 1993, Miller et al. 1995). Lint et al, (1995) found that harvested Gobblers and harvest/effort were useful indices of Gobbler population estimates, and further concluded that Gobbler harvest on TWMA was an accurate index of total wild turkey population trends on TWMA (Figure 1). Gobbler harvest and ancillary observations of hens have declined 250 350% from 1984-92 on TWMA (Hurst unpubl. data, Palmer et al. 1993), indicating a population decline. In addition to predation, Lint et al. (1995) suggested that adverse environmental conditions coupled with predation contributed to the decline of the TWMA wild turkey population. Environmental conditions can not be managed; therefore, managers should focus on controllable factors. Although control of all predators is unwarranted in most cases, control and/or management should be directed at species which have highest impacts on population growth. It has been documented that raccoons influence recruitment of poults into the population by destroying nests (i.e., eggs) at higher frequencies than other predators (Pharris and Goetz 1980, Speake 1980, Miller et al. 1995). Raccoon depredation of points also has been documented (Peoples et al. 1995). With decreasing fur prices and a decrease in recruitment of new trappers, raccoon harvest has decreased in Mississippi in the lastdecade(Steffen 1981-88, Shropshire 1990-94). Our objectives were to determine effects of raccoon depredation an an eastern wild turkey population in Mississippi from 1981-94. Changes in raccoon populations, both state-wide and on a study area (TWMA) in central Mississippi, and their effects on wild turkey recruitment also were ascertained. We would like to thank J. Lipe, C. Shropshire, and G. Linscombe for providing us with harvest data. Thanks also goes to P. Phalen, R Seiss, W. Palmer, J. Lint, K. Godwin, S. Priest, T. Wilson, and D. Lowrey for help in data collection. This study was supported by the National Wild Turkey Federation (NWTF), the Mississippi Chapter of NWTF, U.S. Forest Service, Mississippi State University, and Federal Aid in Wildlife Restoration through the Mississippi Department of Wildlife, Fisheries and Parks.
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Chronology of wild Turkey nesting, gobbling, and hunting in Mississippi
The Journal of Wildlife Management, 1997Co-Authors: Darren A. Miller, George A. Hurst, Bruce D. LeopoldAbstract:Setting dates of spring hunting for wild turkey (Meleagris gallopaco) Gobblers often is based on the belief that 2 peaks of gobbling occur, with the second peak occurring during peak incubation by hens. The second peak offers hunters opportunities to hear Gobblers while protecting hens from inadvertent kill. We examined chronology of gobbling, hunter numbers, harvest and nesting within the framework of a long, liberal spring Gobbler-only hunting season in central Mississippi during 1984-95. Distribution of Gobbler harvest versus initiation of incubation, and hunter numbers versus incubation initiation differed in all years; distribution of Gobblers heard versus initiation of incubation differed during all years except 1995. Distributional relations among hunter numbers, harvest, and Gobblers heard varied among years. Gobblers heard versus harvest, and hunter numbers versus harvest were distributed differently during some years. Only 1 gobbling peak occurred. This lone peak of gobbling was not associated with peak of incubation. Gobbling activity may have been influenced by break up of winter flocks, initiation of egg-laying, and mating opportunities.
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Movements of Wild Turkey Gobblers in Central Mississippi
1994Co-Authors: K. David Godwin, George A. Hurst, Bruce D. LeopoldAbstract:The wild turkey (Meleagris gallopavo) is an important game species throughout the Southeast. While many long-term research projects have provided quantitative data on wild turkey ecology, information on daily Gobbler movements is lacking. Because data on Gobbler mobility may affect habitat and population management, we studied Gobbler movements by radio-telemetry (N = 2,775 loca- tions) on Tallahala Wildlife Management Area, Mississippi. Gobblers (N = 48) were monitored from 1 February 1989 through 30 September 1990 hourly from roost to 1200 hours (morning) and 1300 hours to roost (afternoon) during spring (1 Feb-31 May), summer (1 Jun-30 Sep), and fall/winter (1 Oct-31 Jan). Daily mean distance moved during the morning was 2,492 m for adults and 2,412 m for juveniles in spring 1989. Daily mean distances moved in the morning in spring 1990 by adults (1,228 m) and juveniles (955 m) were significantly (P
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Relationships of Gobbler Population Size to Harvest Characteristics on a Public Hunting Area in Mississippi
1993Co-Authors: John R. Lint, K. David Godwin, George A. Hurst, Bruce D. LeopoldAbstract:Wildlife managers on public hunting areas are accountable for hunter suc- cess rates, annual harvest, and wildlife population size. Understanding the effect of changes in numbers of wild turkey Gobblers (Meleagris gallopavo) on harvest charac- teristics is needed. Population size and harvest characteristics were studied for 9 years on a 14,140-ha public hunting area in central Mississippi. Male wild turkey population size averaged 82, hunter effort averaged 455 hunter-days per season, and an average of 35 male turkeys was harvested per season. Hunter success rates averaged 7.7%, 2.1%, and 5.6% for all males, subadults (jakes), and adults (Gobblers), respectively. For male turkeys released in the winter capture period (7 Jan-4 Mar) and subse- quently harvested that spring (15 Mar-1 May), harvest rates averaged 22.1%, 15.0%, and 35.4% for all males, jakes, and Gobblers, respectively, from 1984 to 1992. Hunter effort was not correlated with male harvests (P = 0.198). Population size was corre- lated with hunter success rate (P = 0.053) and number harvested (P = 0.072). The population declined during the study and it became increasingly difficult for a hunter to be successful, and, in turn, hunter effort eventually decreased. Proc. Annu. Conf. Southeast. Assoc. Fish and Wildl. Agencies 47:170-175
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Determining effective study area size from marked and harvested wild turkey Gobblers
The Journal of Wildlife Management, 1992Co-Authors: John R. Lint, Bruce D. Leopold, George A. Hurst, William J. HamrickAbstract:Study area boundaries often are delineated by subjective methods without considering animal movements and behavior and may result in inaccurate density estimates and incorrect research conclusions. Consequently, we delineated study area boundaries for use with capture-recapture models to calculate density estimates of wild turkey Gobblers (Meleagris gallopavo). From january to March, 1984-89, 189 Gobblers were captured by cannon-net or drug at 38 permanent bait sites in central Mississippi. Fifty-six marked Gobblers were harvested from 17-19 March to 1 May 1984-89. As distance from bait sites increased, proportion of unmarked Gobblers to marked Gobblers increased
James Davis - One of the best experts on this subject based on the ideXlab platform.
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Is spring wild turkey Gobbler harvest additive or compensatory
2008Co-Authors: William Moore, John Kilgo, David Guynn, James DavisAbstract:Abstract: We compared survival rates of eastern wild turkey (Meleagris gallopavo sylvestris) Gobblers in hunted (Crackerneck Wildlife Management Area and Ecological reserve [CWMA]) and unhunted (Savannah River Site [SRS]) populations in South Carolina to assess impact of spring Gobbler-only hunts. Annual survival rate of Gobblers on SRS (0.71) was greater (χ2 = 5.11; df = 1; P = 0.02) than that of Gobblers on CWMA (0.54). Our results indicate that spring Gobbler harvests constitute additive mortality to turkey populations. However, even in years when reproductive rates were relatively low, a spring-only Gobbler harvest rate of 25% appeared to have a minimal effect on turkey populations.
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Effects of hunting and season of fire on wild turkey populations in South Carolina.
2002Co-Authors: William Moore, John Kilgo, David Guynn, James DavisAbstract:This report assesses impacts to wild turkey populations from hunting and prescribed fire. The objectives of the study were as follows: (1) To compare survival rates and causes of mortality of wild turkey Gobblers between hunted and unhunted populations; (2) To determine the effects of dormant versus growing season prescribed burns on nesting success, survival and habitat use of wild turkey hens; (3) To determine the effects of dormant versus growing season prescribed burns on the availability of wild turkey plant foods.
Ferdinand F. Becker - One of the best experts on this subject based on the ideXlab platform.
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Submental W-Plasty for Correction of 'Turkey Gobbler' Deformities
Archives of otolaryngology--head & neck surgery, 1990Co-Authors: Tamara K. Ehlert, J. Regan Thomas, Ferdinand F. BeckerAbstract:• There are many causes and types of submental contour deformities. One such deformity called a turkey Gobbler, is caused by an excess of flaccid submental skin and as an isolated defect is seen more commonly in men. We have found that skin excision and a running submental W-plasty for correction of this deformity yields a superior cosmetic result with excellent camouflage of the submental scar. Two cases are illustrated. ( Arch Otolaryngol Head Neck Surg . 1990;116:714-717)
William Moore - One of the best experts on this subject based on the ideXlab platform.
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Is spring wild turkey Gobbler harvest additive or compensatory
2008Co-Authors: William Moore, John Kilgo, David Guynn, James DavisAbstract:Abstract: We compared survival rates of eastern wild turkey (Meleagris gallopavo sylvestris) Gobblers in hunted (Crackerneck Wildlife Management Area and Ecological reserve [CWMA]) and unhunted (Savannah River Site [SRS]) populations in South Carolina to assess impact of spring Gobbler-only hunts. Annual survival rate of Gobblers on SRS (0.71) was greater (χ2 = 5.11; df = 1; P = 0.02) than that of Gobblers on CWMA (0.54). Our results indicate that spring Gobbler harvests constitute additive mortality to turkey populations. However, even in years when reproductive rates were relatively low, a spring-only Gobbler harvest rate of 25% appeared to have a minimal effect on turkey populations.
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Effects of hunting and season of fire on wild turkey populations in South Carolina.
2002Co-Authors: William Moore, John Kilgo, David Guynn, James DavisAbstract:This report assesses impacts to wild turkey populations from hunting and prescribed fire. The objectives of the study were as follows: (1) To compare survival rates and causes of mortality of wild turkey Gobblers between hunted and unhunted populations; (2) To determine the effects of dormant versus growing season prescribed burns on nesting success, survival and habitat use of wild turkey hens; (3) To determine the effects of dormant versus growing season prescribed burns on the availability of wild turkey plant foods.