Season of birth modifies puberty in female and male goats raised under subtropical conditions

Abstract

In seasonal goats and sheep breeds, onset of puberty is modified by the season of birth. As adult does and bucks from subtropical Mexico display seasonal variation in their reproductive behaviour, this study was carried out to determine the effect of season of birth on puberty. Three groups of each sex born in January, May and October were used. During the seasons, does and bucks were weaned at an age of 30 days and offered ad libitum alfalfa hay and 100 g of commercial concentrate. In the female kids, the onset of ovulatory activity was determined by progesterone plasma concentrations once in a week from 3 months of age until the onset of puberty. In the male kids, the onset of puberty was individually recorded by observing the ability to mount and intromit an induced oestrous female goat aged 3 months and the presence of spermatozoa in the ejaculate obtained in an artificial vagina 1 week after the first mount. In female kids, there was an effect of the season on the date of first ovulation (P < 0.001). In the May group, ovulatory activity commenced at an earlier age (201 ± 3 days) compared with January (264 ± 5 days) and October (344 ± 5 days) groups (P < 0.001). In the January group also, the ovulatory activity commenced earlier than the October group (P < 0.001). In males, an effect of the season of birth on the first mounting was observed (P < 0.001). The male kids that were born in May (111 ± 3) and October (112 ± 5 days) attained puberty earlier than those born in January (131 ± 4 days; P < 0.001). The time of onset of puberty did not differ between groups of May and October. All males showed the presence of spermatozoa in the first ejaculate obtained 1 week after the first mount. The spermatozoa in all ejaculates were immobile. It was concluded that the season of birth modified the onset of puberty in both genders, but these modifications were more pronounced in the female than in the male kid goats.

La Cabra Y Los Sistemas De Producción Caprina De Los Pequeños Productores De La Comarca Lagunera, en El Norte De México

“…However the typical kidding peak occurs from November to February, considering that most producers (90 %) mate their animals from June to September. The majority of producers (90 %) ignore the age that males reach puberty, whereas 10 % indicated that this occurs in the range of 5 to 10 months in line with former reports (Mellado, 2008;Delgadillo et al, 2007), an aspect to be accounted when considering breeding plans.…”

“…Sin embargo, el momento en el que ocurren más partos es de noviembre a febrero, considerando que la mayoría de los productores (90 %) aparean a sus animales de junio a septiembre. Así mismo, la mayoría de los productores (90 %) desconocen la edad en la que los machos llegan a la pubertad; 10 % señaló que esto ocurre en el rango de los 5 a los 10 meses de acuerdo con informes anteriores (Mellado, 2008;Delgadillo et al, 2007), un aspecto que debe ser considerado cuando se habla de planes de mejoramiento.…”

Nutrition level and season of birth do not modify puberty of Payoya goat kids

“…Boer goat kids weaned during the normal breeding season (April/May) exhibit oestrus significantly earlier than those weaned in December (outside the natural season) (Greyling and Van Niekerk, 1990). Creole goat kids born in May began their ovulatory activity at an earlier age compared with kids born in January or October (Delgadillo et al, 2007). In all cases, kids attained puberty during the first breeding season after birth.…”

“…Depending on the time of the year kids are born, they experience different photoperiodic stimuli, so that age at puberty differs according to the season of birth. In northern Mexico, Creole -E-mail: zarazaga@uhu.es she-kids born in May commenced ovulatory activity at an earlier age than those born in January and October (Delgadillo et al, 2007). Papachristoforou et al (2000) observed that Damascus females born in October-November or in February attain puberty at the same time -the following autumn.…”

Improvement of rearing goats in Bali Province, Indonesia

“…This review of literature is limited to the measurements of age of puberty (Freitas et al 2004a;Delgadillo et al 2007), age at first kidding (Abebe 2009;Lopes et al 2012), postpartum interval (Al-Hozab et al 1999;Freitas et al 2004a;Freitas et al 2004b;Abebe 2009), kidding interval (Mani et al 1996;Martin et al 2004), fertility (Abebe 2009), litter size (Alexandre et al 1999;Mellado et al 2006) and annual reproductive rate Sodiq et al 2004;Sodiq & Haryanto 2007;Elieser et al 2012;Adhianto et al 2013). A combination of two or more traits could be used as a measure of reproductive performance.…”