The ferret has been widely used to study both the pathogenicity and the transmissibility of respiratory viral infections, but little is known about how host-associated microbial communities alter disease susceptibility owing to the lack of a validated model. Here, we compared the safety of injectable versus oral broad-spectrum antibiotics and their efficacy in reducing culturable bacteria from the upper respiratory tract of ferrets before an influenza A virus challenge. Both injectable and oral antibiotic treatment led to drastic reductions in cultivable bacteria from nasal wash specimens when assessed after 7 days of ongoing treatment. Even when extended to 14 days, there were few adverse events noted and no clinically significant bloodwork changes. During challenge with either a high-dose or low-dose A(H1N1)pdm09 influenza A virus inoculum, all animals became productively infected and had generally similar viral titers and clinical measurements, regardless of antibiotic pretreatment. Collectively, these results support that both antibiotic regimens evaluated in laboratory ferrets can be utilized to further characterize host-microbial interactions in the context of respiratory viral infections and other pathogens, including a needle-free approach that may be suitable for studies of high-consequence pathogens in containment laboratory facilities.

Type of feed is an important consideration in herbivore colony management, yet limited studies report on the effects of diet on common conditions such as urolithiasis in guinea pigs. Urolithiasis is a well-documented cause of lower urinary tract disease in guinea pigs, with calcium carbonate uroliths reported as the predominant calculi formed in the guinea pig urinary tract. A calcium-rich diet has been suggested as a risk factor for of urolithiasis, with numerous commercially available guinea pig diets formulated for adults avoiding ingredients that are higher in calcium. Due to the high incidence of urolithiasis in our strain 13/N guinea pig colony, we conducted a prospective control study following the implementation of dietary changes aimed at improving overall urinary tract health and reducing risk factors for urolithiasis, thus improving colony welfare. A control group was kept on the original ad libitum alfalfa hay-based pellet diet with restricted loose timothy hay (control diet, 14 juveniles and 24 adults). An experimental group was placed on a portioned, 1 oz daily, timothy hay-based pellet diet with ad libitum loose timothy hay (experimental diet, 21 juveniles and 23 adults). Juveniles and adults were followed for a total of 14 and 26 wk, respectively. Longitudinal blood and urine samples were collected to evaluate blood chemistry and urinary parameters, along with weight and body condition scores to assess general health. Overall, dietary changes did not improve parameters associated with improved urinary tract health or reduced risk of urolithiasis; feeding strategy was not found to meaningfully affect calcium crystalluria, urine protein, urine specific gravity, or renal values. These data support alfalfa hay-based pellet or timothy hay-based pellet, when fed with loose timothy hay, as viable options and suggest that practices aimed at reducing dietary calcium by reducing pelleted diet portions are insufficient to mitigate risk factors for urolithiasis in guinea pigs.