Dominance urine marks

In other rodents, subordinate males also smell scent marks quite often and so keep informed on the presence, status and activities of higher-ranking group members. For instance, dominant males of the hispid cotton rat, Sigmodon hispidus, urine mark more than subordinates. The social status of the male urine donor affects the response of other males to the odor. The response of a reproductive female to feces of either sex depends on her dominance status (Gregory and Cameron, 1989). 

Dominant adult males mark very frequently. This advertises their aggressive dominance over the other resident and intruder males. Dominant males overmark other males urine marks, while marks by dominant males are merely investigated by others. Dominant male marks guide dominant and subordinate males to stay within their territory and to avoid areas marked by other dominant males (Hurst 1990a). Juveniles use urine marks to stay within their parental territory. 

Urine marking is also important in female-female communication. Resident breeding females countermark breeding female urine, especially of neighbors. Females appear to advertise their dominant breeding status to other females by means of urine marks (Hurst 1990b). 

Urine marks also serve communication between the sexes. Dominant males countermark female urine marks at a high rate. Females are attracted to marks by their resident dominant male, but avoid those from neighbor and unfamiliar dominant males (Hurst 1990c). These are just some examples of odors that mice encounter in their daily life and use to extract vital information that guides their behavior. 

In the T-maze we can test the responses of a male or female to a urine mark of the opposite sex, or from dominant or subordinate individuals of the same sex, or some other difference of interest. Among the many studies using two-way choice apparatuses for mice, a good example is a paper by Krasnov and Khokhlova (1996) that deals with mice responding to odors of another rodent species. We will test responses of males and females to urine of the same and different sex in a two-way choice apparatus (T-Maze). 

Dominant males mark differently from subordinate males they cover an entire area, while subordinates urine-mark along the walls of their enclosure or cage, and in fewer and larger patches. These patterns can be visualized under ultraviolet light (Desjardins et al. 1973). 

Drickamer, L. C., 2001, Urine marking and social dominance in male house mice, AeAav. Process. 53 113-120. 

House mice reside together in territorial family groups, consisting of a dominant male with one or more breeding females and subordinate males (Hurst, 1987). Dominant males scent mark their territories extensively with small spots and streaks of urine and will further increase their scent marking rate around competing urine marks found within their territory (Desjardins et al., 1973 Hurst et al., 2001). Dominant males will also... 

We have described how the quality of male scent marks differs between dominants and subordinates accordingly the response of the male receiver differs depending on the type of male mark encountered. If a male competitor attempts to put down urine marks in a pattern that resembles that of a dominant male, or the urinary scent mark is of a similar quality to that of a dominant rather than a subordinate male, then the resident dominant male is more likely to increase his level of aggression by contrast, a subordinate male is likely to flee on encountering the scent mark owner (Jones and Nowell, 1973a Hurst,... 

Patterns of scent marking with urine by bank voles are distinctly different between dominant and subordinate males (Desjardins et al. 1973 Rozenfeld et al. 1987). Dominant males leave fine-tract urine marks especially in locations where conspecifics are likely to encounter them. Subordinate animals, on the other hand urinate in large puddles, usually in locations away from dominate individuals (Rozenfeld Rasmont 1991). Home and Ylonen (1996) used this criteria to assess dominance between male pairs in an arena (60 x 40 x 34 cm) longitudinally divided by a wire mesh partition. Brown craft paper, placed on the arena floor, changed color on contact with urine, which made urination marks and puddles easy to detect. 

In mice, urine is the main source of social odors. Wild house mice (M. domcsticus) families over time build bizarre small posts of solidified urine by repeated marking (Hurst, 1987 Fig. 6.13). A mouse family is habituated to its own background odor, which permeates its living area. The ubiquitous family odor is dominated by the odor of the dominant male and identifies the home area to residents as well as non-residents. (When the author trapped 26 deer mice over... 

Laboratory mice have been used as the model rodent to demonstrate the potential of aversive social odors to manage populations. Chemical constituents in the urine of dominant male mice have been shown to inhibit the exploratory behaviour of subordinate mice in laboratory-based arena studies. Two constituents, a and P-famesene, have been patented as mouse repellents (Novotny, Harvey Jemiolo, 1993). However, we do not know what effect these chemicals have on free-living rodent populations, where dominance hierarchies may not always exist. The scent marks left by dominant male rats within family groups appear to act not so much as warning signals for strange rats, but as aids to orientation (Lund, 1975). In the context of controlling rat populations, social odors are unlikely to produce the immediate reduction in numbers required to control a troublesome rat... 

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