Estrus

Estrogenic activity. Ability to mimic the female hormone by promoting the development of female secondary sex characteristics and modulating the estrus cycle. 

Brunft, /. oestrus, estrus, heat, -honnon, n. (o)estrual hormone. 

Bnmst, /. ardor, fervor oestrus, estrus. brllnstig, a. ardent fervent in heat. 

The influence of polymer composition and molecular weight on the estrus-suppressing activity of the microspheres in female rats was determined. A triphasic release pattern was observed. An initial rapid release over the first few days was attributed to diffusion from superficial areas of the microspheres. A second phase of lower release levels then occurs and continues until the onset of the third, major phase of release. This phase is facilitated by the onset of erosion of the polymer matrix. 

Bronson F. and Marsden H.M. (1964). Male-induced synchrony of estrus in Deermice. Gen Comp Endocr 4, 634-637. 

Fabre-Nys C., Ohkura S. and Kendrick K.M. (1997). Male faeces and odors evoke differential patterns of neurochemical release in the MBH of ewes during estrus an insight into sexual motivation Europ J Neuroscience 9, 1666-1677. 

Fadem B.H. (1989). The effects of pheromonal stimuli on estrus and peripheral plasma estradiol in female gray short-tailed opossums. Biol Reprod 41, 213-217. 

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. 

Ma W. and Klemm W.R. (1997). Variations in equine urinary volatile compounds during the estrus cycle. Vet Res Comm 21, 437-446. 

Ma W., Miao Z. and Novotny M. (1998). Role of the adrenal gland and adrenal-mediated chemosignals in suppression of estrus in the house mouse the Lee-Boot effect revisited. Biol Reprod 59, 1317-1320. 

Ma W., Miao Z. and Novotny M.V. (1999). Induction of estrus in grouped female mice (Mus domesticus) by synthetic analogues of preputial gland constituents. Chem Senses 23, 289-293. 

Marchlewska-Koj A., Pochron E. and Slilwowska, A. (1990). Salivary glands and preputial glands of mice as a source of estrus-stimulating pheromone in female mice. J Chem Ecol 16, 2817-2822. 

Meek L., Lee T Rogers E. and Hernandez R. (1994). Effect of vomeronasal organ removal on behavioral estrus and mating latency in female meadow voles (Microtus pennsylvanicus). Biol Reprod 51, 400-404. 

Novotny M., Ma W., Zidek L. and Daev E. (1999). Recent biochemical insights into puberty acceleration, estrus induction, and puberty delay in the house mouse. In Advances in Chemical Signals in Vertebrates (Johnston R.L., Miiller-Schwarze D. and Sorenson P., eds.), pp. 99-116. 

Perret M. and Barek S. (1991). Male influence on estrus cycles in female Woolly Opossum (Caluromys philander). J Reprod Fertil 91, 557-566. 

Rasmussen L.E.L., Schmidt M.J. and Daves G. (1982). Asian bull elephants Flehmen-like responses to extractable components of female elephant estrus urine. Science 217, 159-162. 

Rivard G. and Klemm W.R. (1989b). Two body fluids containing bovine estrus pheromone(s). Chem Senses 14, 273-280. 

Data suggestive of adverse reproductive effects after an assumed acute oral exposure to organophosphate ester hydraulic fluids are restricted to an observation of reduced lactation and delayed estrus with no coincident gross lesions in cows that ingested grass contaminated with Fyrquel 150 (Beck et al. 1977). 

Carpenter et al. 1959), and decreased lactation and delayed estrus in cows after oral ingestion of Fyrquel-150-contaminated plant tissue at unspecified dose levels (Beck et al. 1977). 

Animal husbandry requires the careful selection and management of breeding stock and a prize stud is an economically valuable asset. The expensive service fee makes it very important that the female be in estrus at the time of mating. In order to... 

F (irregular estrus cycles) 0.28 F (ovarian cysts persistent vaginal estrus) ... 

Rat (Sprague-Dawley) 14-50 ad lib (W) 502 (decreased testicular weights delayed vaginal opening and disruption of estrus cycling) Ronis etal. 1996 PbAc... 

Kriegsfeld, L. J., Hotchkiss, A. K., Demas, G. E., Silverman, A. J., Silver, R. and Nelson, R. J. Brain mast cells are influenced by chemosensory cues associated with estrus induction in female prairie voles (Microtus ochrogaster). Horm. Behav. 44 377-384, 2003. 

Reduced food intake and efficiency of food use, altered iron metabolism, clinical signs of copper deficiency. Onset of puberty delayed 10 weeks, decreased conception rate (fertility 12-33% vs. 57-80% in controls), disrupted estrus cycle (67% were anestrus vs. 7% in controls), and other signs consistent with decreased releases of luteinizing hormones associated with altered ovarian secretion (3, 4) Growth and fertilization normal liver copper 10 mg/kg DW only 16% of embryos developed normally (2)... 

Some information (e.g. reproductive state) appears to be contained solely within the chemical matrix of certain marks, particularly within the stable genital secretions. Thus, longer-lasting signals may be broadcast to any animal that comes in contact with labial or scrotal marks. Such a scenario seems particularly applicable to females that scent mark most frequently prior to the onset of estrus cycles, but nonetheless when their sex steroids are on the rise (Drea 2007). Such advertisement may encourage male immigration at a time that would maximize the opportunity of female mate choice, even if the mechanism of, or criteria for, selection remain obscure. 

Hudson, R., Melo, A.I. and Gonzalez-Mariscal G. (1994) Effect of photoperiod and exogenous melatonin on correlates of estrus on the domestic rabbit. J. Comp. Physiol. A 175, 573-593. 

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