Search

Simple Summary: Mycobacterium kansasii is a zoonotic bacterial pathogen that can cause a chronic disease that resembles pulmonary tuberculosis in many mammals including humans, cattle, goats, black-tailed deer, white-tailed deer, Florida manatees, and rhesus monkeys. We identified the first case of M. kansasii infection in farmed white-tailed deer (Odocoileus virginianus) in Florida. We performed hematoxylin and eosin (H&E) staining, Ziehl–Neelsen (ZN) staining, PCR, and Sanger sequencing of the lung tissue after the animal was euthanized. The microscopic observations of the H&E-stained lung showed multifocal granuloma, while the ZN-stained tissue revealed low numbers of beaded, magenta-staining rod bacteria inside the granuloma formation. Molecular examination identified the presence of Mycobacterium kansasii. Although this was a sporadic case and there was no evidence that M. kansasii could be transmitted directly from animals to human beings, it is crucial to have basic biosecurity practices and management in place to prevent disease outbreaks and spillover. A 7-year-old farmed white-tailed deer doe was transported to a Levy County, Florida property and began to decline in health, exhibiting weight loss and pelvic limb weakness. The doe prematurely delivered live twin fawns, both of which later died. The doe was treated with corticosteroids, antibiotics, gastric cytoprotectants, and B vitamins but showed no improvement. The doe was euthanized, and a post mortem examination was performed under the University of Florida's Cervidae Health Research Initiative. We collected lung tissue after the animal was euthanized and performed histological evaluation, using H&E and Ziehl–Neelsen (ZN) staining, and molecular evaluation, using conventional PCR, followed by Sanger sequencing. The microscopic observations of the H&E-stained lung showed multifocal granuloma, while the ZN-stained tissue revealed low numbers of beaded, magenta-staining rod bacteria inside the granuloma formation. Molecular analysis identified the presence of Mycobacterium kansasii. This isolation of a non-tuberculous Mycobacterium in a white-tailed deer emphasizes the importance of specific pathogen identification in cases of tuberculosis-like disease in farmed and free-ranging cervids. We report the first case of M. kansasii infection in a farmed white-tailed deer (Odocoileus virginianus) in Florida. Although M. kansasii cases are sporadic in white-tailed deer, it is important to maintain farm biosecurity and prevent farmed cervids from contacting wildlife to prevent disease transmission. [ABSTRACT FROM AUTHOR]

Land-use and land-cover change has been a topic that has called the attention of the scientific community for decades. Because of the importance of tropical and subtropical forest ecosystems, investigations into the causes and processes (e.g., underlying and proximate causation) that drive land use and land-cover change have typically concentrated on these regions. Consequently, little work has been done to understand the proximate and underlying drivers of land use and land-cover change in one of the least disturbed forests worldwide, the Paraguayan dry Chaco in South America. This article attempts to fill this gap in the literature by focusing on the processes and drivers behind land-cover change in the Paraguayan Chaco. More specifically, this article links underlying and proximate causes to regional land-cover change. To accomplish this task the study makes use of Moderate Resolution Imaging Spectroradiometer (MODIS) data and census data. Results show major land-cover changes. Different from other dry regions in South America where soybean expansion has been pointed out as main driver of land-cover change, in the Paraguayan Chaco, cattle ranching is a major driver of forest loss. [ABSTRACT FROM AUTHOR]

Anthropogenic habitat alteration has the capacity to alter the distribution of species. Capybara ( Hydrochoerus hydrochaeris) are a widely distributed rodent throughout most of South America, but are restricted to areas of standing water. As the Gran Chaco ecosystem of Paraguay is converted from dry tropical forest to pastureland, we hypothesize that this alteration creates potential for invasion by capybara into newly fragmented areas. We surveyed throughout the Chaco to estimate the distribution of capybara, and we collected noninvasive genetic samples. We used ecological niche modeling based on six environmental or climatic variables, and we modeled both the current distribution of capybara and the distribution of capybara 80 years ago. We then verified the hypothesized demographic signal generated with our model using phylogeographic analyses of 386 bp of the mtDNA control region. Comparison of present and past models suggested that populations expanded into the Gran Chaco after forest was converted to pastureland. Analyses of the mitochondrial D-loop supported the rapid range expansion scenario. We also found evidence of secondary contact of two distinct phylogroups which had previously been disjunct. Anthropogenic land transformation appeared to be a major factor influencing the distribution, as predicted by the niche model and confirmed by genetic data. Habitat modification altered connectivity of populations across the landscape. In addition, long separated clades of capybara are now admixed throughout the Paraguayan Chaco. The invasion of a large bodied herbivore into the High Chaco region may exacerbate the degradation of forest and prevent forest regeneration. As the reservoir host of several zoonotic diseases, the expansion and contact of two previously disjunct capybara populations has implications for disease emergence. [ABSTRACT FROM AUTHOR]

We report the detection and gene coding sequences of three novel Orbivirus species found in six dead farmed white-tailed deer in the United States. Phylogenetic analyses indicate that the new orbiviruses are genetically closely related to the Guangxi, Mobuck, Peruvian horse sickness, and Yunnan orbiviruses, which are thought to be solely borne by mosquitos. However, four of the six viruses analyzed in this work were found as co-infecting agents along with a known cervid pathogen, epizootic hemorrhagic disease virus-2 (EHDV-2), raising questions as to whether the new viruses are primary pathogens or secondary pathogens that exacerbate EHDV-2 infections. Moreover, EHDV-2 is known to be a Culicoides-borne virus, raising additional questions as to whether Culicoides species can also serve as vectors for the novel orbiviruses, if mosquitoes can vector EHDV-2, or whether the deer were infected through separate bites by the insects. Our findings expand knowledge of the possible viral pathogens of deer in the United States. Moreover, due to the close genetic relatedness of the three new orbiviruses to viruses that are primary pathogens of cattle and horses, our findings also underscore a crucial need for additional research on the potential role of the three new orbiviruses as pathogens of other animals. [ABSTRACT FROM AUTHOR]

A 7-year-old farmed white-tailed deer doe was transported to a Levy County, Florida property and began to decline in health, exhibiting weight loss and pelvic limb weakness. The doe prematurely delivered live twin fawns, both of which later died. The doe was treated with corticosteroids, antibiotics, gastric cytoprotectants, and B vitamins but showed no improvement. The doe was euthanized, and a post mortem examination was performed under the University of Florida's Cervidae Health Research Initiative. We collected lung tissue after the animal was euthanized and performed histological evaluation, using H&E and Ziehl-Neelsen (ZN) staining, and molecular evaluation, using conventional PCR, followed by Sanger sequencing. The microscopic observations of the H&E-stained lung showed multifocal granuloma, while the ZN-stained tissue revealed low numbers of beaded, magenta-staining rod bacteria inside the granuloma formation. Molecular analysis identified the presence of Mycobacterium kansasii . This isolation of a non-tuberculous Mycobacterium in a white-tailed deer emphasizes the importance of specific pathogen identification in cases of tuberculosis-like disease in farmed and free-ranging cervids. We report the first case of M. kansasii infection in a farmed white-tailed deer ( Odocoileus virginianus ) in Florida. Although M. kansasii cases are sporadic in white-tailed deer, it is important to maintain farm biosecurity and prevent farmed cervids from contacting wildlife to prevent disease transmission.