03261naa a2200349 a 450000100080000000500110000800800410001902400540006010000200011424501240013426000090025852022680026765000180253565000090255365000090256265000170257165000200258865000100260865000130261865000170263165000250264865000110267365000100268465000170269465000270271165300300273865300190276865300100278765300240279765300190282177300710284015219072023-12-07       1987    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1016/0168-1591(87)90014-12DOI1 aTILBROOK, A. J.  aThe influence of factors associated with oestrus on the sexual 'attractiveness' of ewes to rams.h[electronic resource]  c1987  aAbstract: The influence on sexual ?attractiveness? of ewes of the stage of oestrus of the ewes, the dose of oestradiol benzoate (ODB) used to induce oestrus, the oestrous state of the ewes and the order that the ewes had been detected in oestrus were considered in 4 experiments. In the first experiment, 12 rams were individually presented with 4 oestrous ewes that were in proportionately different stages of oestrus, and the amount of mating and courtship directed from the rams to the ewes in 3 h was recorded. For Experiment 2, two groups of ovariectomised ewes of known sexual ?attractiveness? were placed in each group. After a period of progesterone priming, oestrus was induced in 3 of the ewes in each group with an injection of 50 ?g ODB, while the other 3 ewes in each group received an injection of 150 ?g ODB. Ten rams then ranked the ewes in each group for ?attractiveness?. In Experiment 3, an attempt was made to get the 10 rams to rank the ewes from Experiment 2 for sexual ?attractiveness? when the ewes were not in oestrus. In Part 1 of Experiment 4, a ram was placed with 6 ovariectomised ewes that had been prepared to come into oestrus and the animals were observed continuously. When a ewe permitted mounting, she was considered to be in oestrus and was removed from the pen. In this way the order that the ewes were detected in oestrus was established and the ram was then permitted to rank this group of oestrous ewes for ?attractiveness?. Ten rams were used, each with a different group of ewes. Vasectomized rams were used in Part 2 of this experiment to detect the order that a group of 6 ewes came into oestrus, and then the 10 rams ranked these ewes for ?attractiveness?. Stage of oestrus had no significant influence on the amount of sexual behaviour directed from the rams to the ewes, and sexual ?attractiveness? was not significantly related to the dose of ODB used to induce oestrus or the order that the ewes had been detected in oestrus. It was necessary for ewes to be in oestrus to get maximum discrimination and sexual response from the rams. Most of the components of the sexual ?attractiveness? of ewes appear to be associated with oestrus, and it seems that these factors are stable between and within oestrous periods.  aEstrous cycle  aEwes  aRams  aReproduction  aSexual behavior  aSheep  aCarneiro  aCiclo Estral  aComportamento Sexual  aOvelha  aOvino  aReprodução  aSincronização do Cio  aComportamento reprodutivo  aDosage effects  aEstro  aOestradiol benzoate  aOestrous cycle  tApplied Animal Behaviour Sciencegv. 17, n. 1/2, p. 117-128, 1987.