Drug developers worldwide assess compound safety and efficacy using measures that include mouse core temperature and locomotor activity. Subtle differences in animal housing conditions between institutions can alter these values, impacting scientific rigor and reproducibility. In these studies, adult male NIH Swiss mice were surgically implanted with radiotelemetry probes that simultaneously monitored core temperature and locomotor activity across various housing conditions. In the first study, ambient temperature was varied between 20 °C and 28°C in groups of singly housed mice. Additional studies held the mice at a constant ambient temperature and examined the effects of cage density (housing animals singly or in groups of 3 or 6), bedding change and provision of nesting material, and the availability of a running wheel on core temperature and locomotor activity. Mice overwhelmingly maintained species-typical core temperatures across all ambient temperatures, across all housing conditions, when bedding was fresh or old, and with or without the provision of cotton squares as nesting material. However, engaging in wheel running and the combination of fresh bedding and cotton squares transiently increased core temperatures beyond the species-typical range. Similarly, the circadian distribution of locomotor activity was significantly disrupted by placing animals in cages with fresh bedding or nesting material, or by performing both of these manipulations concurrently during the light period. These findings suggest that standard husbandry practices and common housing conditions may transiently affect core temperature in adult mice. Furthermore, these practices may have profound and relatively long-lasting effects on motor activity and the regulation of circadian rhythms.

We determined the sensitivity of perianal tape impressions to detect Syphacia spp. in rats and mice. We evaluated 300 rat and 200 mouse perianal impressions over 9 wk. Pinworm-positive perianal tape impressions from animals with worm burdens at necropsy were considered as true positives. Conversely, pinworm-negative perianal tape impressions from animals with worm burdens were considered false negatives. The sensitivity of perianal tape impressions for detecting Syphacia muris infections in rats was 100%, and for detecting Syphacia obvelata in mice was 85.5%. Intermittent shedding of Syphacia obvelata ova is the most probable explanation for the decreased sensitivity rate we observed in mice. We urge caution in use of perianal tape impressions alone for Syphacia spp. screening in sentinel mice and rats.

Here we discuss the importance of monitoring noise in contemporary animal facilities. Noise surveys and monitoring should be an integral part of an institution's Occupational Health and Safety Program. If noise levels equal or exceed 85 dB, then a Hearing Conservation Program must be initiated in accordance with Occupational Safety and Health Administration standards. The tenets of a comprehensive Hearing Conservation Program are outlined.

The tropical rat mite, Ornithonyssus bacoti, was identified in a colony of mutagenized and transgenic mice at a large academic institution. O. bacoti is an obligate, blood-feeding ectoparasite with an extensive host range. Although the source of the infestation was likely feral rodents, none were found in the room housing infested mice. We hypothesize that construction on the floor above the vivarium and compromised ceiling integrity within the animal room provided for vermin entry and subsequent O. bacoti infestation. O. bacoti infestation was eliminated by environmental decontamination with synthetic pyrethroids and weekly application of 7.4% permethrin-impregnated cotton balls to mouse caging for five consecutive weeks. Visual examination of the macroenvironment, microenvironment, and colony for 38 days confirmed the efficacy of treatment. We noted no treatment-related toxicities or effects on colony production.

Cocaine abuse during pregnancy is associated with adverse perinatal outcome, believed to be a result of potent vasoconstrictive effects that cocaine has on the maternal cardiovascular system. The direct effect of cocaine on the pregnant, nonhuman primates' uterine vasculature in vivo has not been examined. We investigated the effects of intravenous cocaine on maternal arterial blood pressure, uterine blood flow, and uterine vascular resistance in four unanesthetized, chronically instrumented pregnant baboons. Baboons were instrumented during the latter half of pregnancy, placing an ultrasonic flow probe around one uterine artery and catheters in the maternal inferior vena cava and aorta. Bolus intravenous cocaine hydrochloride doses of 0.05 mg/kg, 0.1 mg/kg, and 0.3 mg/kg by maternal weight were infused 30 minutes apart at least 5 days after surgical instrumentation. The maternal blood pressure rose 7.3% and 12.0% after the 0.1 mg/kg and 0.3 mg/kg cocaine infusions, respectively, and the uterine blood flow fell in a dose-dependent fashion 13.1% and 22.7%. Plasma norepinephrine levels rose in response to the 0.3 mg/kg cocaine infusion. These studies show that low doses of cocaine significantly reduce uterine blood flow in the pregnant baboon in a dose-dependent manner by increasing uterine vascular resistance.