Pre-and early postpartum maternal behavior in the New Zealand white rabbit consists of an elaborate pattern of nestbuilding behavior that results in a straw nest built in a burrow, lined with loosened fur plucked from the female's ventrum. By contrast, postpartum maternal behavior is abbreviated, consisting of a single brief daily visit to the nest (< 4 min) during which the female nurses the pups at the same time daily for about a month. Serum levels of estradiol, testosterone, progesterone, and prolactin obtained from females during pregnancy and lactation have been correlated with nestbuilding behavior, food intake, and nursing. Studies are proposed on ovariectomized females to stimulate burrowing behavior, straw carrying, hair loosening, plucking and carrying to the nest, and to determine the hormonal regulation of food intake and nursing behavior using systemic injections of these hormones and blocking prolactin release with bromocryptine. Brain implants of appropriate hormones will be used to delineate brain regions responsive to hormonal stimulation of nestbuilding and nursing. Behavioral interactions during nestbuilding will be studied by shaving females to prevent use of hair providing hair obtained by shaving the female, or preventing hair loosening by blocking enzymatic reduction of testosterone. Female dependence on pup stimulation to maintain maternal responsiveness postpartum will be studied by early separation from the pups and by stimulus restriction during the prolonged contact which occurs on the first day, and, in addition, by depriving females of pup stimulation during the first week by anesthetizing them during the daily nursing.

National Institute of Health (NIH)
National Institute of Mental Health (NIMH)
Method to Extend Research in Time (MERIT) Award (R37)
Project #
Application #
Study Section
Psychobiology and Behavior Review Committee (PYB)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Rutgers University
Veterinary Sciences
Other Domestic Higher Education
United States
Zip Code
Gonzalez-Mariscal, Gabriela; Chirino, Rosario; Rosenblatt, Jay S et al. (2005) Forebrain implants of estradiol stimulate maternal nest-building in ovariectomized rabbits. Horm Behav 47:272-9
Gonzalez-Mariscal, G; Chirino, R; Flores-Alonso, J C et al. (2004) Intracerebroventricular injections of prolactin counteract the antagonistic effect of bromocriptine on rabbit maternal behaviour. J Neuroendocrinol 16:949-55
Caba, M; Rovirosa, M J; Beyer, C et al. (2003) Immunocytochemical detection of progesterone receptor in the female rabbit forebrain: distribution and regulation by oestradiol and progesterone. J Neuroendocrinol 15:855-64
Caba, Mario; Beyer, Carlos; Gonzalez-Mariscal, Gabriela et al. (2003) Immunocytochemical detection of estrogen receptor-alpha in the female rabbit forebrain: topography and regulation by estradiol. Neuroendocrinology 77:208-22
Melo, Angel I; Gonzalez-Mariscal, Gabriela (2003) Placentophagia in rabbits: incidence across the reproductive cycle. Dev Psychobiol 43:37-43
Gonzalez-Mariscal, G; Cuamatzi, E; Rosenblatt, J S (1998) Hormones and external factors: are they ""on/off"" signals for maternal nest-building in rabbits? Horm Behav 33:1-8
Gonzalez-Mariscal, G; Melo, A I; Chirino, R et al. (1998) Importance of mother/young contact at parturition and across lactation for the expression of maternal behavior in rabbits. Dev Psychobiol 32:101-11
Rosenblatt, J S; Ceus, K (1998) Estrogen implants in the medial preoptic area stimulate maternal behavior in male rats. Horm Behav 33:23-30
Mayer, A D; Rosenblatt, J S (1998) A method for regulating the duration of pregnancy and the time of parturition in Sprague-Dawley rats (Charles River CD strain). Dev Psychobiol 32:131-6
Gonzalez-Mariscal, G; Melo, A I; Jimenez, P et al. (1996) Estradiol, progesterone, and prolactin regulate maternal nest-building in rabbits. J Neuroendocrinol 8:901-7

Showing the most recent 10 out of 11 publications