Journal of the American Association for Laboratory Animal Science : JAALAS最新文献

Disinfectant application to gloved hands before handling SPF mice is standard practice to minimize transmission of pathogens and microbial contamination between cages. The risk of contamination with murine pathogens on gloves as well as the efficacy of disinfectant application for this step is largely unknown. This study aimed to determine if murine norovirus (MNV), Helicobacter spp., and Rodentibacter spp. are detectable on gloved hands and, if they are, to evaluate how effective the application of a hydrogen peroxide-based disinfectant (Rescue) or 70% ethanol is in reducing the transfer of these pathogens while handling multiple cages of mice. Mice with natural infections of these pathogens were handled without the application of any disinfectant and the gloves were swabbed for PCR testing. All pathogens were detected via PCR with Helicobacter spp. the most frequently transferred in 83% of the cages handled. The mice were then divided into 4 treatment groups based on the product applied to gloves before handling: Rescue, 70% ethanol, sterile water, and no product. Mice in each cage were briefly handled, and the gloves were swabbed with ATP swabs after each cage and swabs for PCR testing after handling 4 and 9 cages, consecutively. All pathogens were detected via PCR in all treatment groups, and neither Rescue nor 70% ethanol was superior to water or no product in reducing contamination. Rescue and 70% ethanol were effective in maintaining lower levels of organic microbial contamination than water and no product for consecutive handling of up to 3 and 4 cages of mice, respectively. This study indicates that exposure to MNV, Helicobacter spp., and Rodentibacter spp. from handling mice is a risk and the application of Rescue or 70% ethanol is not completely effective in eliminating transfer of these pathogens.

Cardiac troponin I (cTnI) is a cardiac-specific biomarker, used for the detection of myocardial injury. While rabbits develop naturally occurring cardiovascular disease, they are also an animal model for human disease; thus, rapid detection of cTnI has implications for both veterinary and human medicine. The objective of this study was to validate and establish a reference interval for a point-of-care (POC) cTnI assay in New Zealand White rabbits. In the first portion of the study, rabbit cardiac and skeletal muscle tissues were used to create homogenates, serially diluted with saline or rabbit whole blood, and run by repeated analysis on the POC assay. In the second portion of the study, a reference interval of peripheral whole blood cTnI was determined by robust methods from 49 New Zealand White rabbits. The least diluted cardiac muscle homogenates produced detectable cTnI (mean 23.12 ± 3.557 ng/mL), while skeletal muscle homogenates produced low to undetectable cTnI. The CV ranged from 0.00% to 32.51% for cTnI of diluted cardiac muscle homogenates. Rabbit cardiac homogenate diluted in blood had a linear relationship to cTnI concentration (Y = 0.2254 × X + 0.5396, R2 = 0.975). The reference interval for cTnI in this population was less than 0.04 ng/mL. This POC assay may be useful when rapid detection of cTnI is needed and differentiation between normal and elevated values is required. Given the high CV, this assay may not be appropriate for cases that require high sensitivity or detection of low concentrations of cTnI.

Soft-pelleted, high-fat diets (HFD) are greasy and crumble easily leading to food wastage and hair coat grease accumulation when mice are fed using commercially available feeders. The ideal HFD feeder design should reduce food wastage, facilitate mouse weight gain, and minimize variables such as hair coat grease accumulation that have the potential to alter scratching behaviors. Our study compared the feeding efficiency of 2 commercially available feeders (feeders A and E) to 4 novel feeder designs (feeders B, C, D, and F). Novel feeders had alterations in feeding aperture size, feeding surface area, feeder configuration, and level of food presentation. Male C57BL/6NCrl mice (n = 120; 4/cage) were randomly assigned to cages containing one of the 6 feeder types and were fed HFD for 12 wk. Feeders and cage bottoms were weighed before use and then weekly at the time of cage change. Mice were weighed before starting the HFD and then biweekly. Scratching behavior was video recorded at 0, 4, 8, and 12 wk. Hair coat grease accumulation was visually scored biweekly. Feeder A use was associated with the highest feed cost due to HFD wastage ($36.98 ± 1.54/cage/wk). Mice fed using Feeder A had the highest average weight gain (23.75 ± 0.8 g, P < 0.005). However, mice also had significantly higher hair coat grease accumulation scores (P < 0.05) and significantly increased scratching frequency at 4 wk (P < 0.05) when compared with mice fed using other feeder types. Novel feeder designs utilized 10 to 21 times less HFD dispensed when compared to feeder A. Mice fed using novel feeders also displayed improved welfare, as evidenced by low hair coat grease accumulation scores, and no significant differences in scratching frequency when compared with baseline behavior.

A variety of fish species have proven instrumental in the investigation of evolution, behavior, ecology, and physiology, among many other fields. Many model systems (e.g., zebrafish, guppies, and three-spined sticklebacks) have been maintained by institutions and have had protocols written with respect to their husbandry. Here we present the protocols we have developed to maintain and breed a variety of Corydoras catfish species, which are native to the tropical Americas. Corydoras species are excellent systems for investigating behavior, ecology, and other topics, and our husbandry protocols would be suitable for nearly every species in the genus. In addition, these protocols are appropriate for a variety of softwater Amazonian species, and we present options for a variety of housing and husbandry conditions. On the whole, we suggest that, in a scientific laboratory setting, the use of remineralized reverse osmosis water is most appropriate and that in context, a single measure, total dissolved solids, can be used to monitor the water chemistry for water introduced to fish enclosures.