Advances in research on the biology of the desert rodent Gerbillus tarabuli: a review.

Selection of the appropriate species and strain of laboratory animals are among the scientist's major concerns. Tarabul's gerbil (Gerbillus tarabuli) is a small, seasonally breeding, desert rodent native to Africa. Despite its unique biological features, which make it an ideal model candidate for biomedical research, only a few reports have used it in research. Hence, the present review aims to provide more data about this species, covering all aspects of its biology, such as taxonomy, morphology, anatomy, ecology, wildlife biology, molecular biology, physiology, neurobiology, genetics, reproduction, development, evolutionary biology, and conservation biology, and covers current progress in exploration of G. tarabuli, discussing its valuable characteristics, which are widely useful for research in various fields. This review paper is destined for biologists, scientists, mammologists, zoologists, academics, and students.

Effects of prolonged night-time light exposure and traffic noise on the behavior and body temperature rhythmicity of the wild desert rodent, Gerbillus tarabuli.

The aim of this study was to demonstrate for the first time in Tarabul's gerbils (Gerbillus tarabuli), the effects of simultaneous exposure to two major environmental stressors - light and noise pollutions - on the body temperature rhythm and anxious behavior. Seven groups, each consisting of 6 adult male gerbils, were subjected to a standard LD cycle (12 L:12D) with lights on at 08:00 h and off at 20:00 h, constant conditions (total darkness, DD), prolonged nighttime exposure to light (PEL: 18 L:6D) with lights on at 08:00 h and off at 02:00 h, mimicking prolonged exposure to light pollution in peri-urban areas, exposure to auditory stress (TNS) of 80 dB, and conditions combining PEL&TNS. The body temperature circadian rhythm was recorded, and behavioral tests were performed at the end of experimental phases. The results revealed the existence, for the first time in Gerbilus tarabuli, of an endogenous circadian rhythm of body temperature with a period of 23.8 ± 0.04 h. Prolonged exposure to light at night (PEL) induced a significant phase delay (02 h 09 min ± 0.16 h) of the rhythm, with an acrophase (peak time) occurring at 04:42 ± 0.13 h instead of 02:33 ± 0.21 h. Exposure to TNS for 4 hours per night induced a significant increase of the amplitude of the rhythm and a decrease of the rhythm regularity (robustness of 73.26% in TNS vs. 82.32 in control condition). While combining TNS and PEL significantly delayed the phase of the Tb rhythm by 3 h 10 min (acrophase at 06:39 ± 0.37 h instead of 02:33 ± 0.21 h), increased the amplitude, and significantly reduced the stability of the rhythm (robustness of 67.25% in PEL&TNS vs. 82.32 in control condition). PEL&TNS and TNS environments induce an important stress in gerbils highlighted by a significant decrease of the number of line crossings and time spent in the center area of the open field test. Furthermore, elevated plus maze test revealed gerbils of the PEL&TNS and TNS conditions significantly visited the lowest number of open arms and spent a shorter amount of time in it. In addition, these conditions were responsible for less activity (total number of entries in arms) than in the control and PEL conditions. These results indicate clearly that in the desert area, peri-urban light and noise pollutions disturb the circadian rhythm components and alter the behavior of Tarabul's gerbils inducing an anxious state.