Opossum domestica

Several studies have identified responses that do not involve VN participation, from marsupials to Mouse-lemurs. Where the chosen endpoint is totally unaffected by absence of the organ and in addition is dependent upon MOS activity, then it needs to be classified as VN-independent. Where VN-x results are ambiguous, as already considered for opossums (Monodelphis domestica), further analysis is desirable. For instance, Goats do not use AOS input for mating, only urinalysis, although experiential variables have not been fully explored (Ladewig et al., 1980). Examples of VN independence then exist in both altricial and precocial species. 

Brunjes P.C., Jazaeri A. and Sutherland M.J. (1992). Olfactory bulb organization and development in Monodelphis domestica, the Grey Short-tailed Opossum. J Comp Neurol 320, 544-554. 

Cummings D., Knsab B. and Brunjes P. (1997). Effects of unilateral olfactory deprivation in the developing opossum Monodelphis domestica. J Neurobiol 33, 429-438. 

Jackson L.M. and Harder J.D. (1996). Vomeronasal organ removal blocks pheromonal induction of estrus in Gray Short-tailed Opossums (Monodelphis domestica). Biol Reprod 54, 506-512. 

Jia C. and Halpem M. (1998). Neurogensis and migration of receptor neurons in the vomeronasal sensory epithelium of the Opossum Monodelphis domestica. J Comp Neurol 400, 287-297. 

Martinez-Marcos A. and Halpem M. (1999b). Differential projections from the anterior and posterior divisions of the accessory olfactory bulb to the medial amygdala in the opossum, Monodelphis domestica. Europ J Neurosci 11, 3789-3799. 

Poran N. (1998). Vomeronasal organ and its associated structures in the opossum Monodelphis domestica. Micros Res Techn 43, 500-510. 

Roland R., Halpem M., et al. (1995). Effects of vomeronasal-axotomy on the anatomy of the accessory olfactory bulb and on nuzzling behavior in the Brazilian Shorttailed Opossum Monodelphis domestica. Chem Senses 19, 544-545. 

Schwanzel-Fukuda M., Fadem B., Garcia M. and Pfaff D. (1988). Immunocytochemical localization of LHRH in the brain and Nervus terminalis of the adult and early neonatal Gray Short-Tailed opossum (Monodelphis domestica). J Comp Neurol 276, 44-60. 

Shapiro L., Roland R.M., Li C.S. and Halpem M. (1996) Vomeronasal system involvement in response to conspecific odors in adult male opossums, Monodelphis domestica. Behav Brain Res 77, 101-113. 

Stonerook M.J. and Harder J.D. (1992). Sexual maturation in female grey short-tailed opossums M. domestica, is dependent upon male stimuli. Biol Reprod 46, 290-294. 

Puberty acceleration has also been found in a marsupial. The odor left behind in a cage by a male can accelerate the time of first estrus in a female gray, shorttailed opossum, Monodelphis domestica, from 161 to 126 days of age (Stonerook and Harder, 1989). 

Stonerook, M. J. and Harder, J. D. (1989). Male pheromones advance the age of first estrus in the gray, short-tailed opossum, Monodelphis domestica. Biology ofRepmduction 40(Suppl.l), 157. 

SEXUAL DIMORPfflSM IN THE ACCESSORY OLFACTORY BULB AND VOMERONASAL ORGAN OF THE GRAY SHORT-TAILED OPOSSUM, MONODELPHIS DOMESTICA... 

Since the vomeronasal system is involved in pheromone recognition, a sexually dimorphic activity, and because prior studies have reported sex differences in the VNO and AOB of rats, we pursued this question in the opossum Monodelphis domestica. An additional interest was to determine if the two parts of the vomeronasal system are... 

Six adult male-female pairs of litter mates from six different mothers of the opossum species Monodelphis domestica were used for this study. At five months of age, the body weight and length of each animal was recorded immediately before it was deeply anesthetized and transcardially perfused with saline followed by Bouin s fixative. 

Shapiro, L. S., and Halpem, M., 1998, Devdopment of NADPH-diaphorase expression in chemosensory systems of the opossum, Monodelphis domestica. Dev. Brain Res. 111 51 -63. 

Shapiro, L S., Li, C-S., Jia, C-P., and Halpem, M., 1993, Histochemical, immunocytochemical and tract tracing studies investigating the heterogeneity of the primary vomeronasal pathway in the Brazilian gray short-tailed opossum, Monodelphis domestica, Chem. Senses lO-m-llt. 

CHEMICAL COMMUNICATION IN GRAY SHORT-TAILED OPOSSUMS (MONODELPHIS DOMESTICA) WITH COMPARISONS TO OTHER MARSUPIALS AND WITH REFERENCE TO MONOTREMES... 

Various aspects of chemical communication have recently been studied and reported for one South American didelphid, the gray shorttailed opossum (Monodelphis domestica), hereafter referred to as the gray opossum. Scent-marking behavior was described and conspecific responses to olfactory cues quantified in a recent study (Fadem and Cole, 1985). 

Fadem, B. H., 1985, Evidence for the activation of female reproduction by males in a marsupial, the gray short-tailed opossum (Monodelphis domestica), Biol. Reprod., in press. 

Fadem, B. H., and Rayve, R, S., 1985, Characteristics of the oestrous cycle and influence of social factors in grey short-tailed opossums (Monodelphis domestica), Reprod. Fert., 73 337. 

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