FISIOLOGIA DA REPRODUÇÃO
(Reproductive physiology)
ARTIGOS
Kreeger TJ, 1992 Influence of hypothalamic-pituitary-adrenocortical hormones on reproductive hormones in gray wolves (Canis lupus). J Exp Zool 264(1), 32-41 (1992)
Asa CS, 1987 Pinealectomy or superior cervical ganglionectomy do not alter reproduction in the wolf (Canis lupus). Biol Reprod 37(1), 14-21 (1987)
Asa CS, 1986 Effect of anosmia on reproduction in male and female wolves (Canis lupus). Behav Neural Biol 46(3), 272-284 (1986)
Asa CS, 1990 The influence of social and endocrine factors on urine-marking by captive wolves (Canis lupus). Horm Behav 24(4), 497-509 (1990)
Raymer J, 1984 Volatile constituents of wolf (Canis lupus) urine as related to gender and season. Experientia 40(7), 707-709 (1984)
TESES
Raymer, James Howard. INVESTIGATIONS INTO THE CHEMICAL NATURE OF CHEMO-OLFACTORY COMMUNICATION IN THE WOLF (CANIS LUPUS) (PHEROMONES). Dissertation Abstracts International. Volume: 45-09, Section: B, page: 2899. Abstract Chemo-olfactory communication is undoubtedly the least understood form of canid communication. The high resolving power of capillary gas chromatography, when combined with mass spectrometry and Fourier transform infrared spectroscopy, is capable of providing information about the chemical structures of the individual scent components. Additional information is often required for unambiguous structure elucidation. A selective isolation and derivatization procedure for carbonyl compounds is described. In addition, a study correlating GC retention of model ketones with molecular connectivity is described which is shown to be useful for structural characterization. The volatile components found in urine samples derived from males, females, and castrate males were compared. Methyl propyl, methyl butyl, and methyl isopentyl sulfides were found in male urine at higher levels than those in female or castrate male urines. Also, a series of methyl-substituted 2-alkanones followed the same trend. Female and castrate male urine samples contained some compounds (e.g., 3-ethylcyclopentanone and acetophenone) found to be more abundant than in male urine. Similar studies with anal gland secretions indicated statistically significant differences between genders. Thus, the endocrinological state of the animal can be communicated via scent-marking with these fluids. By manipulation of the endocrinological state and correlating changes in the composition of the volatiles of the urine with this state, putative pheromones can be searched for in complex mixtures. The hormonal dependence of several compounds (methyl-substituted 2-alkanones, methyl propyl sulfide, and methyl isopentyl sulfide in the male) was demonstrated, suggesting an important communicational role of these compounds. Behavioral tests with the wolves were conducted by incorporating such compounds into test mixtures then presenting these to the animals. The results indicated a clear preference for the sulfides and methyl-substituted 2-alkanones, thereby, implicating their importance in chemo-olfactory communication. Finally, the urinary volatiles from seven canids species were compared. Preliminary evidence indicates that the scent alone is sufficient to allow differentiation among species. The possibility was also examined that the similarity in the urinary volatiles was a function of the phylogenetic relatedness of the species studied.
Peterson, ERIC Karl. PROLACTIN AND SEASONAL REPRODUCTION IN WOLVES (LH, CORTISOL). Dissertation Abstracts International. Volume: 45-08, Section: B, page: 2468. Abstract Information on the annual variation of prolactin (PRL) in strong seasonal breeders has been obtained mainly from studies with short day breeders. The purpose of this study was to evaluate whether non-domesticated long day breeders have an annual variation of PRL levels and, if present, to relate the variation to seasonal breeding. The carnivore Canis lupus (wolf), an animal that breeds as daylight increases, was selected as a representative long day breeder. Heterologous application of the NIADDK cPRL RIA was evaluated and results suggested that this RIA was valid for measuring PRL in this species. In most cases samples were obtained from drug immobilized animals. Unless otherwise stated male and female data were not different. Prolactin levels varied annually (summer 40-100ng/ml, winter 1-5ng/ml) due to secretion (TRH stimulation--summer = 76ng/ml, winter = 39ng/ml) rather than clearance (t 1/2- summer = 38.5min, winter = 42.6min) of PRL. An extended light cycle during the winter months induced a significant increase in serum PRL (experimental = 60-100ng/ml; control = 1-10ng/ml). Mean 24-hour secretion profiles of PRL in unanesthetized wolves indicated that there was a significant difference between summer (19 (+OR-) 3ng/ml) and winter (6 (+OR-) 2ng/ml). Serum LH levels and secretory peak frequency during these times were inversely related to PRL levels (summer--2.2 (+OR-) 0.2ng/ml, 5.2 (+OR-) 0.9 pks/24hr; winter--5.1 (+OR-) 0.3ng/ml, 12 (+OR-) 1.2 pks/24hr). Mean 24-hour serum testosterone (males) levels varied proportionately to serum LH levels in both summer (42.5 (+OR-) 4.5 ng/dl) and winter (94 (+OR-) 20 ng/dl). Summer bromocriptine treatment decreased serum PRL levels. There was no difference in biological indicators of steroid production or baseline LH levels following bromocriptine treatment. However, there was a significant increase in serum testosterone in males when PRL levels were decreased. In conclusion, PRL levels in wolves vary seasonally in response to photoperiod. Additionally, biological indicators of reproduction, serum LH, and testosterone levels have an inverse relationship to serum PRL levels in these animals. It is unclear if PRL in wolves has an inhibitory effect on LH secretion but this may occur in males.
Packard, Jane Martia. DEFERRED REPRODUCTION IN WOLVES (CANIS LUPUS). Dissertation Abstracts International. Volume: 41-07, Section: B, page: 2465.
Última atualização: 22/02/1998