Seasonal peculiarities of female hormonal response of females to conspecific chemical signals of the male in two species of the genus Phodopus

Abstract

An important adaptation to a solitary mode of life is preferential orientation to information perception through olfactory signals. In solitary species, to which striped hairy footed hamsters belong (for instance, the desert hamster Phodopus roborovskii and the Djungar ian hamster P. sungorus), odors of excreta left on the substrate by females and males play an important role in the organization of sexual and social relationships. To determine whether and how perception of the same signals changes depending on the season is very important in the context of understanding specific fea tures of chemical communications between individu als of these species in different seasons.In some papers the considerable role of the season in the regulation of the efficiency of the effect of odor signals in mice of the lineage Swiss Webster (Vanden bergh et al., 1975) and ICR/Alb (Drickamer, 1984) has been shown: maximum efficiency is in the springsummer period. However, it is not clear from these data what determines such variation: an increased sen sitivity to odor signals, seasonal change in its activity, or a combination of the effect of these factors. How ever, it is known that the attractiveness of the odor of male urine of the laboratory mouse of the lineage BALB/c during testing on females does not change throughout the year (Kaneko et al., 1980). At the same time, there are data that in the spring-summer period males and females of the Pennsylvanian vole Microtus pennsylvanicus produce odors attracting individuals of the opposite sex, and in the autumn-winter period, to the contrary, males do not demonstrate a preference for odors of conspecifics, while females are attracted by odor signals of other females (Leonard and Ferkin, 1999).The study of behavioral and hormonal responses of males of three species of feather legged hamsters to odors of urine, secretion of the midventral gland (MVG), and excreta of females demonstrated signifi cant seasonal differences in these responses (Feoktis tova and Naidenko, 2006, 2007;Feoktistova et al., 2010).The purpose of our study was to determine the pat tern of seasonal sensitivity of two species of hamsters of the genus Phodopus to natural excreta (urine and MVG) of conspecific males on the basis of measuring the level of sex steroids (progesterone, estradiol) and glucocorticoid (cortisol) after exposure to urine and secretion of MVG and comparison of the obtained results between the species.The problem of the hormonal response of females to chemical signals of conspecific males is rather poorly studied, but is very urgent. With reference to several species of mammals, it was shown that the administration of estradiol and progesterone causes in females an active search for partners (Lindsay and Fletcher, 1972). The sexual activity of pigs is con trolled by estradiol (Signoret, 1970). In studies of prai rie voles Microtus ochrogaster (Dluzen et al., 1981), it was shown that one time placing of the urine of mature males on the lip of females can cause both an Abstract-Changes in di...

The physiological reaction of Siberian hamsters (Phodopus sungorus, Cricetidae) to chemical signals of perspective mating partners before and during courtship

“…In those studies, females in 30-min tests showed a significant increase in progesterone levels in response to the scent of urine and abdominal gland secretion for conspecific males in the winter and summer. No significant changes in estradiol and cortisol levels were observed in this species in response to exposure to male chemosignals ( Kropotkina et al, 2012 ). It has been shown previously that fecal samples are an additional source of chemosignals for Siberian hamsters in the summer ( Novikov, 1988 ).…”