Do we still need a canary in the coal mine for laboratory animal facilities? A systematic review of environmental health monitoring versus soiled bedding sentinels.

Introduction: Despite increasing evidence that Environmental Health Monitoring (EHM) is an effective method to perform rodent colony health surveillance, promotes the 3Rs as a Replacement, is comparable or reduces cost, and demonstrates labor benefits, many research institutions continue to use live Soiled Bedding Sentinels (SBS). Some veterinarians and others responsible for rodent colony health monitoring remain cautious of the evidence supporting this new technology. Therefore, our objective was to perform a formal systematic review to identify, summarize, and evaluate the research on the efficacy of EHM as compared to SBS.

A Cross-sectional Survey on Rodent Environmental Health Monitoring Practices: Benchmarking, Associations, and Barriers.

Tens of thousands of rodents are used each year in Rodent Health Monitoring programs. However, Environment Health Monitoring (EHM) could replace sentinel rodent use while maintaining or even improving diagnostic quality. Despite its advantages, widespread implementation of EHM appears to be relatively low.

Effects of chronic Helicobacter pylori strain PMSS1 infection on whole brain and gastric iron homeostasis in male INS-GAS mice.

Iron deficiency, the most common micronutrient deficiency in humans, is associated with long-term deficits in cognition and memory if left untreated. Infection with the gastric pathogen Helicobacter pylori has been linked to iron deficiency anemia (IDA). The H.

Carbon Dioxide, Oxygen, and Ammonia Levels in Mouse and Rat Disposable IVC Removed from Mechanical Ventilation.

Maintenance of an appropriate microenvironment for rodents used in research is of paramount importance because changes in environmental parameters such as O₂ and humidity can influence animal health and welfare and potentially alter research results. Here we evaluated the microenvironment of mouse and rat disposable cages after removal from mechanical ventilation in order to guide recommendations for their use. Cages with sealed IVC lids, unsealed lids (partially ajar), and lids without the exhaust filter (for rats) or static lids (for mice) were removed from the ventilated rack and were thereafter monitored CO₂, O₂, and NH₃ levels.

Validation of Sanitization Practices in Single-use Individually Ventilated Mouse Cages at Standard and Thermoneutral Temperatures.

Vivarium husbandry practices are based on performance data and adhere to applicable regulatory guidelines. Refinements in husbandry and optimization of sanitization protocols improve animal wellbeing and help standardize the microenvironment, contributing to research reproducibility. The objective of this study was to evaluate the microenvironment to establish performance standards for mouse husbandry and sanitization, including housing at standard and thermoneutral temperatures.

Using Filter Media and Soiled Bedding in Disposable Individually Ventilated Cages as a Refinement to Specific Pathogen-free Mouse Health Monitoring Programs.

Molecular-based methods have shown potential for improving pathogen detection and reducing animal use. While increasing evidence supports rodent-free environmental health PCR pathogen detection, limited information is available regarding efficacy for disposable individually ventilated caging systems. In such systems, testing of plenum exhaust air dust is ineffective, and the use of collection media is optimal.

Automated monitoring of respiratory rate as a novel humane endpoint: A refinement in mouse metastatic lung cancer models.

In oncology research, while xenograft tumor models are easily visualized and humane endpoints can be clearly defined, metastatic tumor models are often based on more subjective clinical observations as endpoints. This study aimed at identifying objective non-invasive criteria for predicting imminent distress and mortality in metastatic lung tumor-bearing mice. BALB/c and C57BL/6 mice were inoculated with CT26 or B16F10 cells, respectively.

Daily Water Intake by Common Marmosets () and Recommendations Regarding Fluid Regulation.

The typical daily water intake of common marmosets () in a research setting has not been well characterized. Because these New World primates are in demand as animal models for neurobehavioral experiments, which can include the potential use of fluid regulation for training, veterinary and research staff need to understand how marmosets keep hydrated under normal circumstances. In the current study, we measured the water consumption of older (age, 5 to 12 y; = 11) and younger (age, 1 to 2 y; = 11) marmosets every 3 h during the 12-h light phase in 2 different months (January and July).

Lung Lobe Torsion in an Adult Male Common Marmoset ().

A 6-y-old, intact, pair-housed male common marmoset (Callithrix jacchus) presented with acute onset dyspnea and tachypnea immediately after sedation with alfaxalone; a history of gradual weight loss initiated the examination under sedation. Thoracic radiographs revealed significant right-lung consolidation, with a vesicular gas pattern in the right caudodorsal lung field, pleural effusion, and dorsal displacement of the heart. The marmoset was euthanized due to his unstable condition and poor prognosis.

Endothelial siRNA delivery in nonhuman primates using ionizable low-molecular weight polymeric nanoparticles.

Dysfunctional endothelial cells contribute to the pathophysiology of many diseases, including vascular disease, stroke, hypertension, atherosclerosis, organ failure, diabetes, retinopathy, and cancer. Toward the goal of creating a new RNA-based therapy to correct aberrant endothelial cell gene expression in humans, efficient gene silencing in the endothelium of nonhuman primates was achieved by delivering small interfering RNA (siRNA) with 7C1, a low-molecular weight, ionizable polymer that forms nanoparticles. After a single intravenous administration of 1 mg of siRNA per kilogram of animal, 7C1 nanoparticles delivering Tie2 siRNA caused Tie2 mRNA levels to decrease by approximately 80% in the endothelium of the lung.