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Comparative Medicine Dec 2020The internal transcribed spacer (ITS) regions of , , , , and and of a related β-hemolytic taxon isolated from laboratory rodents were studied for their feasibility...
The internal transcribed spacer (ITS) regions of , , , , and and of a related β-hemolytic taxon isolated from laboratory rodents were studied for their feasibility to discriminate among these species. The 6 species analyzed showed species-specific ITS patterns that were shared by the type strains and clinical isolates and that allowed their identification. Nevertheless, differentiating between the ITS band patterns of and is visually challenging. In all species tested, sequence analysis of the ITS fragments revealed a larger ITS, which contained the genes for tRNA and tRNA , and a smaller ITS with the tRNA gene. The ITS sequences varied among the 6 species evaluated, displaying identity levels ranging from 62% to 86% for ITS and 68% to 90% for ITS. Overall, ITS amplification proved to be a reliable method to differentiate among these important species of laboratory rodents. Moreover, the ITS sequence variations recorded here might facilitate the design of probes for specific identification of these species. The ability to diagnose these organisms to the species level could increase our understanding of their clinical significance.
Topics: Animals; DNA, Bacterial; Pasteurella pneumotropica; Pasteurellaceae; RNA, Ribosomal, 16S; RNA, Ribosomal, 23S; Rodentia; Sequence Analysis, DNA
PubMed: 33121574
DOI: 10.30802/AALAS-CM-99-990085 -
Laboratory Animals Apr 2021An otherwise healthy two-month-old female C57BL/6J mouse presented with a left-sided head tilt. Differential diagnoses included idiopathic necrotizing arteritis,...
An otherwise healthy two-month-old female C57BL/6J mouse presented with a left-sided head tilt. Differential diagnoses included idiopathic necrotizing arteritis, bacterial otitis media/interna (, , , and ), encephalitis, an abscess, neoplasia, a congenital malformation and an accidental or iatrogenic head trauma. Magnetic resonance imaging (MRI) revealed a large space-occupying right olfactory lobe intra-axial lesion with severe secondary left-sided subfalcine herniation. Following imaging, the animal was euthanized due to poor prognosis. Histopathologic examination revealed a unilateral, full-thickness bone defect at the base of the cribriform plate and nasal conchae dysplasia, resulting in the herniation of the olfactory bulb into the nasal cavity. There was also a left midline-shift of the frontal cortex and moderate catarrhal sinusitis in the left mandibular sinus. The MRI and histopathologic changes are consistent with a congenital malformation of the nasal cavity and frontal aspect of the skull known as an ethmoidal meningoencephalocele. Encephaloceles are rare abnormalities caused by herniation of contents of the brain through a defect in the skull which occur due to disruption of the neural tube closure at the level anterior neuropore or secondary to trauma, surgical complications, cleft palate or increased intracranial pressure. The etiology is incompletely understood but hypotheses include genetics, vitamin deficiency, teratogens, infectious agents and environmental factors. Ethmoidal encephaloceles have been reported in multiple species including humans but have not been reported previously in mice. There are multiple models for spontaneous and induced craniofacial malformation in mice, but none described for ethmoidal encephaloceles.
Topics: Animals; Diagnosis, Differential; Encephalocele; Ethmoid Bone; Fatal Outcome; Female; Magnetic Resonance Imaging; Meningocele; Mice; Mice, Inbred C57BL
PubMed: 32787540
DOI: 10.1177/0023677220944449 -
Veterinary World Dec 2019A total of 112 freshly dead ducks aged from 2 to 20 weeks old with a history of respiratory manifestations were investigated for the implication of family members.
AIM
A total of 112 freshly dead ducks aged from 2 to 20 weeks old with a history of respiratory manifestations were investigated for the implication of family members.
MATERIALS AND METHODS
Isolation and identification to the family level were conducted by conventional bacteriological methods, including microscopic examination and biochemical characterization. Identification to the species level was conducted by polymerase chain reaction (PCR) and analytical profile index (API) 20E kits.
RESULTS
Conventional bacteriological isolation and biochemical characterization revealed the infection of 16/112 examined birds with a prevalence rate of 14.3%. PCR confirmed the detection of family conserved genes B and z in 16/16 (100%) isolates. PCR was also used for genus and species identification of the isolated members; the results revealed that 5/16 (31.3%) of isolates were and 2/16 of isolates (12.5%) were . , , and were not detected by PCR. Biotyping by API 20E successfully identified 5/16 (31.3%) isolates that could not be typed by PCR and confirmed their belonging to . Neither the available PCR primer sets nor API 20E succeeded for species identification of 4/16 (25%) isolates. Antibiotic susceptibility profiling of isolates revealed that 16/16 (100%) of isolates demonstrated multidrug resistance (MDR) phenotypes. Moreover, 16/16 (100%) of isolates demonstrated a phenotypic resistance pattern to neomycin.
CONCLUSION
Combined genotypic, phenotypic, biotyping, and virulence characterizations are required for laboratory identification of pathogenic . Moreover, was not the prevailed member implicated in respiratory problems in ducks as , , and unidentified strains were involved with higher prevalence. Chloramphenicol and ampicillin demonstrated the highest effects on the studied . Furthermore, the prevalence of multidrug-resistant isolates signified the demand to implement targeted surveillance in the ducks' production sector, and MDR survey in poultry sectors in Egypt to apply effective control measures.
PubMed: 32095060
DOI: 10.14202/vetworld.2019.2061-2069 -
Journal of the American Association For... Jan 2020To monitor rodent colony health in research facilities, soiled-bedding sentinel (SBS) animals have traditionally been used. SBS can be tested by various methods, which...
To monitor rodent colony health in research facilities, soiled-bedding sentinel (SBS) animals have traditionally been used. SBS can be tested by various methods, which may include serology, PCR analysis, and necropsy. Several pathogens are unreliably detected by using SBS or transmitted poorly through soiled bedding, and collection and evaluation of SBS samples can be time-intensive. Recently, exhaust air dust (EAD) testing through PCR analysis has emerged as an adjunct or replacement method for rodent colony health monitoring. EAD monitoring may provide a more efficient, sensitive, and humane method for monitoring health status. Using both EAD and SBS health monitoring, we evaluated colony health over the course of 1 y in 3 research barrier rooms in which mice were housed exclusively on IVC racks. Three pathogens- spp., spp. (previously ), and murine norovirus (MNV)-were not excluded in 2 of the rooms, and we expected that these mice would test positive with some regularity. EAD monitoring was significantly more sensitive than SBS for detection of the bacterial agents. SBS failed to detect spp. at time points when EAD had 100% detection in the rooms that did not exclude the bacteria. The detection of MNV did not differ between health monitoring systems at any time point. The findings suggest that EAD is especially valuable in detecting bacteria poorly transmitted through soiled bedding. In addition, the corresponding results with MNV detection suggest that EAD surveillance can reliably be implemented as an alternative to SBS monitoring in a facility in which mice are housed exclusively on IVC racks.
Topics: Animals; Bacterial Infections; Bedding and Linens; Caliciviridae Infections; Dust; Helicobacter; Housing, Animal; Laboratory Animal Science; Mice; Norovirus; Pasteurellaceae; Rodent Diseases; Sentinel Surveillance
PubMed: 31862019
DOI: 10.30802/AALAS-JAALAS-19-000061 -
Journal of the American Association For... Jul 2019The uncertain taxonomy of [] and other rodent has hindered the acquisition of knowledge on the biology and disease for this group of bacteria. Recently, these...
The uncertain taxonomy of [] and other rodent has hindered the acquisition of knowledge on the biology and disease for this group of bacteria. Recently, these organisms have been reclassified within the new genus In this study, we documented which of the new described spp. are present in the mouse and rat microbiologic units of an experimental facility. Screening all of the microbiologic units populated with mice and rats yielded 51 isolates. Molecular and phenotypic diagnosis indicated the colonization of mice by and , whereas and were found in rats. Overall, we document the association of laboratory rodents with 3 of the newly described . Diagnostics of the spp. at the species level can decisively contribute to the progress of knowledge on these bacteria.
Topics: Animals; Laboratory Animal Science; Mice; Pasteurellaceae; Pasteurellaceae Infections; Rats; Rodent Diseases
PubMed: 31239009
DOI: 10.30802/AALAS-JAALAS-19-000001