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Free-ranging nilgai antelope (Boselaphus tragocamelus) are an understudied species, both on their native ranges of India, Pakistan, and Nepal and on their introduced ranges in southern Texas. Basic data related to population sizes, survival, reproduction, and recruitment are needed throughout their range to inform management and conservation decisions. We collected nilgai fetuses from 3 ranches in southern Texas, including East Foundation's El Sauz and Santa Rosa ranches, and the Norias Division of the King Ranch® from 2018-2021. We calculated the percentage of individuals that were pregnant in each of the sample years and overall. We determined monthly average, maximum, and minimum fetus length. Of 488 nilgai cows, we found 386 to be pregnant (79%) and 214 to be pregnant with twins (56%). We found nilgai cows as young as 1-year old to have fetuses and therefore to have reached sexual maturity. Sex ratios of fetuses during any sampling year did not differ. We found ample evidence supporting our hypothesis that nilgai are fecund on their introduced range of southern Texas. To prevent nilgai overpopulation and associated problems, harvest management strategies should be implemented, specifically on nilgai cows.
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Rose-ringed parakeets (Psittacula krameri) are one of the most widespread invasive avian species worldwide. This species was introduced to the island of Kaua'i, Hawai'i, USA, in the 1960s. The rapidly increasing population has caused substantial economic losses in the agricultural and tourism industries. We evaluated the efficacy of a roost culling program conducted by an independent contractor from March 2020 to March 2021. We estimated island-wide minimum abundance was 10,512 parakeets in January 2020 and 7,372 in April 2021. Over 30 nights of culling at four roost sites, approximately 6,030 parakeets were removed via air rifles with 4,415 (73%) confirmed via carcasses retrieval. An estimated average of 45 parakeets were removed per hour of shooter effort. The proportion of adult females removed in 2020 was 1.9 × greater when culled outside of the estimated nesting season. Of the four roosts where culling occurred, the parakeets fully abandoned three and partially abandoned one site. Of the three fully abandoned roosts, an estimated average of 29.6% of birds were culled prior to roost abandonment. The roost culling effort was conducted during the COVID-19 pandemic, when tourist numbers and foot traffic were greatly reduced. It is unknown how public perception of roost culling in public areas may impact future efforts. Findings suggest roost culling can be utilized for management of nonnative rose-ringed parakeet populations when roost size is small enough and staff size large enough to cull entire roosts in no greater than two consecutive nights (e.g., if two shooters are available for three hours per night, roost culling should only be attempted on a roost with ≤ 540 rose-ringed parakeets). Supplementary Information: The online version contains supplementary material available at 10.1007/s10530-022-02984-3.
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Free-ranging white-tailed deer (Odocoileus virginianus) across the United States are increasingly recognized for infection and transmission of SARS-CoV-2. Through a cross-sectional study of 80 deer at three captive cervid facilities in central and southern Texas, we provide evidence of 34 of 36 (94.4%) white-tailed deer at a single captive cervid facility seropositive for SARS-CoV-2 by neutralization assay (PRNT90), with endpoint titers as high as 1,280. In contrast, all tested white-tailed deer and axis deer (Axis axis) at two other captive cervid facilities were seronegative, and SARS-CoV-2 RNA was not detected in respiratory swabs from deer at any of the three facilities. These data support transmission among captive deer that cannot be explained by human contact for each infected animal, as only a subset of the seropositive does had direct human contact. The facility seroprevalence was more than double of that reported from wild deer, suggesting that the confined environment may facilitate transmission. Further exploration of captive cervids and other managed animals for their role in the epizootiology of SARS-CoV-2 is critical for understanding impacts on animal health and the potential for spillback transmission to humans or other animal taxa. IMPORTANCE As SARS-CoV-2 vaccine coverage of the human population increases and variants of concern continue to emerge, identification of the epidemiologic importance of animal virus reservoirs is critical. We found that nearly all (94.4%) of the captive white-tailed deer at a cervid facility in central Texas had neutralizing antibodies for SARS-CoV-2. This seroprevalence is over double than that which has been reported from free-ranging deer from other regions of the United States. Horizontal transmission among deer may be facilitated in confinement. Tracking new infections among wild and confined deer is critical for understanding the importance of animal reservoirs for both veterinary and human health.
Assuntos
COVID-19 , Cervos , Animais , COVID-19/epidemiologia , COVID-19/veterinária , Vacinas contra COVID-19 , Estudos Transversais , Humanos , SARS-CoV-2 , Estudos Soroepidemiológicos , Texas/epidemiologiaRESUMO
Baylisascaris procyonis is a zoonotic parasite that can cause serious health issues in their intermediate hosts. Eggs of the parasite are shed in the feces of raccoons (Procyon lotor), the definitive host, and can remain viable in the environment for years. Temperatures at 49 C are the LD50 for B. procyonis eggs. Our objective was to determine the effect of prescribed fire as a lethal control technique for B. procyonis eggs. Aliquots of 1,000 viable B. procyonis eggs were placed on the soil surface and at a depth of 2 cm within 10×10 m grass plots consisting of approximately 2,000 kg/ha and 4,000 kg/ha fuel loads. In addition, aliquots of 1,000 viable B. procyonis eggs were placed at 0, 0.7, 1.2, and 1.8 m from the fire's edge and within a 1 m2 circle of bare ground on the leading edge, center of circle, and trailing edge of the fire of similar plots. Prescribed fire killed B. procyonis eggs on the soil surface up to 0.7 m from the fire's edge at fuel loads of 4,000 kg/ha but was ineffective at depths of 2 cm. Fuel loads of 2,000 kg/ha killed only 50% of B. procyonis eggs on the soil surface at the fire's edge but was not effective killing eggs at greater distances or at soil depths. Prescribed fire can be used to reduce the quantity of B. procyonis eggs on the soil surface within an environment but will not be effective in eradicating the parasite eggs.
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Ascaridoidea , Incêndios , Óvulo , Animais , Solo , TemperaturaRESUMO
Pronghorn (Antilocapra americana) are native to western North America and are found in 24 Association of Zoos and Aquariums (AZA)-accredited institutions. Acute-phase proteins (APP) are a broad class of proteins that are stimulated in response to inflammation and have been shown to be a sensitive measure of inflammation in equids and ruminants. In this study, blood samples from clinically normal free-ranging and captive populations of pronghorn were analyzed using assays for protein electrophoresis (EPH) and APP, including serum amyloid A (SAA) and haptoglobin (HP), to develop preliminary ranges to gauge potential differences between these populations. Additional samples were taken from clinically abnormal captive pronghorn with facial abscesses. By EPH measurements, albumin: globulin ratio mean and SE were significantly different (P <0.05) with 1.02 (0.08) for captive populations and 1.91 (0.05) for free-ranging populations. Total protein mean and SE were significantly different (P <0.05) for captive and free-ranging populations, respectively 5.6 (0.3) g/dl and 6.9 (0.1) g/dl. Mean and SD of SAA for captive pronghorn were 1.4 (3.2) mg/L, and were significantly different from the free-ranging population, which was below the limits of detection for (P <0.05). There was no difference in HP levels between these groups. In a case study of a pronghorn with facial abscesses, elevated levels of HP, but not SAA, suggested that HP maybe useful in certain disease states. Future studies should explore the use of these biomarkers as tools to monitor general health, prognosis, and subclinical disease.
Assuntos
Proteínas de Fase Aguda/metabolismo , Animais Selvagens/sangue , Animais de Zoológico/sangue , Eletroforese das Proteínas Sanguíneas/veterinária , Ruminantes/sangue , Animais , Feminino , Masculino , América do Norte , Valores de Referência , TexasRESUMO
Serum samples from 18 axis deer ( Axis axis ) and 19 fallow deer ( Dama dama ) were analyzed with an enzyme-linked immunosorbent assay for Neospora caninum antibodies. Two axis (11%) and two fallow deer (11%) were positive for N. caninum antibodies.
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Coccidiose/veterinária , Cervos/parasitologia , Neospora/isolamento & purificação , Animais , Ensaio de Imunoadsorção Enzimática , MéxicoRESUMO
Sixteen Chilean flamingos, Phoenicopterus chiles, and 10 red-tailed hawks, Buteo jamacensis, were vaccinated in the pectoral muscle with 0.2 ml of a commercially produced killed West Nile virus vaccine intended for use in horses. Half the birds of each species received a booster vaccination 3 weeks after the first injection. Three weeks after the booster vaccination, none of 13 birds surveyed had detectable antibody to West Nile virus.