title: Lesion of the main olfactory epithelium facilitates maternal behavior in virgin rabbits.
abstract: Maternal behavior is induced in virgin female rabbits (normally unresponsive to foster pups) by removing the accessory olfactory bulbs. To determine if the main olfactory system (MOS) plays a similar inhibitory role in the present work we investigated the effect of lesioning the olfactory epithelium with a ZnSO(4) spray on the facilitation of maternal behavior in New Zealand white virgin rabbits. Four days after the chemical lesion 40% of females showed behaviors indistinguishable from those of normal mothers, i.e.: rapid entrance into the nest box containing the pups, adoption of a crouching posture over them, acceptance of suckling, and exit from the nest box after ca. 3min. The proportion of females showing these behaviors rose to 70% by day 14 post-lesion. Ovariectomized rabbits sprayed with ZnSO(4) or animals sprayed with NaCl did not behave maternally. ZnSO(4) also provoked a transient reduction in olfactory perception: before the lesion animals from all groups directed significantly more sniffs to a flask containing male urine than to one containing water. This difference was abolished in ZnSO(4)-sprayed females (intact and ovariectomized) for 3-6 days post-lesion and was re-established by 7-9 days. NaCl did not provoke such transitory hyposmia. ZnSO(4) lesions did not provoke malaise in the animals, as determined by food intake and the frequency of scent-marking and ambulation. Results suggest that olfactory cues from the pups are aversive to virgin rabbits and that a transitory reduction in their perception (accompanied by the action of ovarian secretions) is enough to facilitate maternal responsiveness.
authors.affiliation: Centro de Investigación en Reproducción Animal, CINVESTAV-Universidad Autónoma de Tlaxcala, Mexico.
authors.forename: Rosario
authors.initials: R
authors.lastname: Chirino
authors.forename: Carlos
authors.initials: C
authors.lastname: Beyer
authors.forename: Gabriela
authors.initials: G
authors.lastname: González-Mariscal
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001522:Behavior, Animal; D004435:Eating / Q000187:drug effects / Q000502:physiology; D005260:Female; D008425:Maternal Behavior / Q000187:drug effects / Q000502:physiology*; D009831:Olfactory Mucosa / Q000187:drug effects / Q000293:injuries* / Q000502:physiology*; D010052:Ovariectomy / Q000379:methods; D011817:Rabbits; D012903:Smell / Q000187:drug effects / Q000502:physiology; D013997:Time Factors; D019287:Zinc Sulfate / Q000633:toxicity
chemical_list: D019287:Zinc Sulfate