Importance of the signals provided by the buck for the success of the male effect in goats.
Under temperate and subtropical latitudes, ewes and goats display a reproductive seasonal pattern and their sexual activity during the anestrous period can be stimulated and synchronized by the introduction of males in the group, which is called the "male effect". The response of females to the male effect in the middle of the anestrous season is weak or absent. This failure may be due to the inability of the female to respond to males, as a result of a refractoriness of the female to the male stimulus. But, it may also be due to a low quality stimulus provided by the male which is, as the females, in seasonal rest. We tested this latter hypothesis in seasonally inactive goats kept under subtropical conditions by comparing the use of males with their sexual behavior stimulated or not by photoperiodic treatments. Treated males were able to induce estrous activity of females during the whole anestrus season. We have also determined that previous separation of the males and continuous contact during teasing are not absolute requisites when active bucks are used. While odor from the male and its sexual behavior play a primary role in inducing ovulation, vocalizations appear to facilitate the display of the does' estrous. It remains to be determined to which extent these conclusions apply under temperate latitudes and with more seasonal breeds.
Delgadillo
J Alberto
JA
Centro de Investigación en Reproducción Caprina, Universidad Autónoma Agraria Antonio Narro, Periférico Raúl López Sánchez y Carretera a Santa Fe, CP 27054, Torreón, Coahuila, México. joaldesa@yahoo.com
Flores
J Alfredo
JA
Véliz
Francisco G
FG
Duarte
Gerardo
G
Vielma
Jesús
J
Hernandez
Horacio
H
Fernandez
Ilda G
IG
D000818:Animals; D002980:Climate; D004971:Estrus / Q000502:physiology*; D005260:Female; D006041:Goats / Q000502:physiology*; D008297:Male; D009812:Odorants / Q000032:analysis; D017440:Photoperiod; D012098:Reproduction / Q000502:physiology; D012621:Seasons; D012724:Sex Attractants / Q000502:physiology*; D012726:Sexual Behavior, Animal / Q000502:physiology*; D014828:Vocalization, Animal / Q000502:physiology*
D012724:Sex Attractants