Physiologic reference ranges for captive black-tailed prairie dogs (Cynomys ludovicianus)

Abstract

The black-tailed prairie dog (Cynomys ludovicianus) is a member of the order Rodentia and the family Sciuridae. Ecologically, prairie dogs are a keystone species in prairie ecology. This species is used as an animal model for human gallbladder disease and diseases caused by infection with Clostridium difficile, Yersinia pestis, Francisella tularensis, and most recently, Orthopoxvirus. Despite increasing numbers of prairie dogs used in research and kept as pets, few data are available on their baseline physiology in animal facility housing conditions. To establish baseline physiologic reference ranges, we designed a study using 18 wild-caught black-tailed prairie dogs. Telemetry data were analyzed to establish circadian rhythms for activity and temperature. In addition, hematologic and serum chemistry analyses were performed. Baseline measurements were used to establish the mean for each animal, which then were compiled and analyzed to determine the reference ranges. Here we present physiologic data on serum chemistry and hematology profiles, as well as weight, core body temperature, and daily activity patterns for black-tailed prairie dogs. These results reflect the use of multiple measurements from species- and age-matched prairie dogs and likely will be useful to ecologists, scientists interested in using this animal model in research, and veterinarians caring for pet prairie dogs.

Figure 1.

A literature review was performed to identify pathogens that can infect prairie dogs. These pathogens, and the human diseases that can be modeled in the prairie dog, are listed with appropriate references.

Figure 2.

Weight (g) ranges for 5- to 7-mo-old prairie dogs are shown. Each age group represents 4 measurements of each of 18 animals. The graph shows the median (line), 25th and 75th percentiles for each data set (box), and the 5th and 95th percentiles for each data set (whiskers). The dotted line represents the 5th and 95th percentile for all values.

Figure 3.

Core body temperature (°C) was measured every 5 min for each prairie dog over a 30-d period (7640 readings per animal; 137,520 total readings). The mean values of all readings and the 5th and 95th percentiles were graphed on an hourly basis over a 24-h period. The fixed light:dark cycle under which the animals were housed is annotated. The graph shows the median (line), 25th and 75th percentiles for each data set (box), and 5th and 95th percentiles for each data set (whiskers).

Figure 4.

Daily activity (gross motor activity; counts) was measured every 5 min for each animal over a 30-d period (7640 readings per animal, 137,520 total readings). The mean values of all readings and the 5th and 95th percentiles were graphed on an hourly basis over a 24-h period. The fixed light:dark cycle under which the animals were housed is annotated. The graph shows the median (line), 25th and 75th percentiles for each data set (box), and the 5th and 95th percentiles for each data set (whiskers).