Jose Alberto Delgadillo, D. Lopez-Magaña, H. Hernandez, J. Vielma, J.A. Abecia


Background. In anestrous goats exposed to sexually active male goats ("male effect"), more than 90% display estrus and ovulate, but only 70% give birth. Objective. To determine the causes that reduce fertility at birth of goats exposed to the male effect. Methodology. Twenty-nine goats in seasonal anestrus that had a body condition of 1.3 ± 0.05 were used. Three adult male goats were exposed from November 1 to January 15 to artificial long days (16 h of light per day) followed by natural photoperiod. The three males were introduced into the group of goats on March 29, remaining with them for 15 days. Subsequently, from day 16 (April 13), only one male provided with a ventral harness to prevent copulation remained with the females until the end of the observations. Estrus, ovulations, pregnancies and their evolution over time were determined. Results. All goats were detected in estrus, and 28 of 29 ovulated. Most of the goats (23/29) were diagnosed pregnant 38 days after the introduction of males, and this proportion did not differ from that registered at 72 days (18/29; P = 0.09). Of the 23 females diagnosed pregnant at 38 days, 16 gave birth. Of the 13 goats that did not give birth, six returned to the anestrus after having presented estrus behavior associated or not with ovulations; four lost the embryo between days 45 and 58; one was diagnosed as pseudopregnant at 58 days and two aborted at 95 and 129 days of pregnancy. Implications. These results show that fertility at kidding is reduced in goats exposed to sexually active male goats, most likely due to the low body condition of the females. A nutritional supplementation could improve the fertility of females exposed to the male effect. Conclusion. The results obtained in this study allow us to conclude that returning to anestrus, embryo losses and abortions reduce the fertility of goats subjected to the male effect during the seasonal anestrus.


goats; male effect; estrous behavior; ovulation; post-implantation losses.

Full Text:



Abecia JA, Sosa C, Forcada F. and Meikle, A., 2006. The effect of undernutrition on the establishment of pregnancy in the ewe. Reproduction, Nutrition and Development, 46, pp. 367-378.

Araya, J., Bedos, M., Duarte, G., Herna?ndez, H., Keller, M., Chemineau, P. and Delgadillo, J.A., 2016. Maintaining bucks over 35 days after a male effect improves pregnancy rate in goats. Animal Production Science, 57, pp. 2066-2071.

Aron?a, R.M., Mun?oz, A.L., Herna?ndez, H., Ungerfeld, R., Keller, M., Chemineau, P. and Delgadillo, J.A., 2023. Seasonally anestrus goats mated by sexually active bucks can become refractory to the presence of bucks. Tropical and Subtropical Agroecosystems, 26, #01.

Ashworth, C.J., Toma, L.M. and Hunter, M.G., 2009. Nutritional effects on oocyte and embryo development in mammals: implications for reproductive efficiency and environmental sustainability. Philosophical Transactions of the Royal Society B, 364, pp. 3351-3361.

Brooks, K., Burns G. and Spencer T.E., 2014. Conceptus elongation in ruminants: roles of progesterone, prostaglandin, interferon tau and cortisol. Journal of Animal Science and Biotechnology, 5, p. 53.

Chasles, M., Chesneau, D., Moussu, C., Delgadillo, J.A., Chemineau, P. and Keller, M., 2016. Sexually active bucks are efficient to stimulate female ovulatory activity during the anestrous season also under temperate latitudes. Animal Reproduction Science, 168, pp. 86-91.

Chemineau, P., 1983. Effect on oestrus and ovulation of exposing Creole goats to the male at three times of the year. Journal of Reproduction and Fertility, 67, pp. 65-72.

Chemineau, P., Daveau, A., Maurice, F. and Delgadillo, J.A., 1992. Seasonality of estrus and ovulation is not modified by subjecting female Alpine goats to a tropical photoperiod. Small Ruminant Research, 8, pp. 299-312.

De Brun, V., Meikle, A., Ferna?ndez-Foren, A., Forcada, F., Palaci?n, I., Menchaca, A., Sosa, C. and Abecia, J.A., 2016. Failure to establish and maintain a pregnancy in undernourished recipient ewes is associated with a poor endocrine milieu in the early luteal phase. Animal Reproduction Science, 173, pp. 80–86.

Delgadillo, J.A., Canedo, G.A., Chemineau, P., Guillaume, D. and Malpaux, B., 1999. Evidence for an annual reproductive rhythm independent of food availability in male creole goats in subtropical northern Mexico. Theriogenology, 52, pp. 727– 737.

Delgadillo, J.A., Flores, J.A., Véliz, F.G., Hernández, H., Duarte, G., Vielma, J., Poindron, P., Chemineau, P. and Malpaux, B., 2002. Induction of sexual activity in lactating anovulatory female goats using male goats treated only with artificially long days. Journal of Animal Science, 80, pp. 2780–2786.

Delgadillo, J.A., Cortez, M.E., Duarte, G., Chemineau, P. and Malpaux, B., 2004. Evidence that the photoperiod controls the annual changes in testosterone secretion, testicular and body weight in subtropical male goats. Reproduction, Nutrition and Development, 44, 183-193.

Delgadillo, J.A., Flores, J.A., Herna?ndez, H., Poindron, P., Keller, M., Fitz-Rodri?guez, G., Duarte, G., Vielma, J., Ferna?ndez, I.G. and Chemineau, P., 2015. Sexually active males prevent the display of seasonal anestrus in female goats. Hormones and Behavior, 69, pp. 8–15.

Duarte, G., Flores, J.A., Malpaux, B. and Delgadillo, J.A., 2008. Reproductive seasonality in female goats adapted to a subtropical environment persists independently of food availability. Domestic Animal Endocrinology, 35, pp. 362–370.

Duarte, G., Nava, M.P., Malpaux, B. and Delgadillo, J.A., 2010. Ovulatory activity of female goats adapted to the subtropics is responsive to photoperiod. Animal Reproduction Science, 120, pp. 65–70.

Lozano, J.M., Lonergan, P., Boland, M.P. and O’Callaghan, D., 2003. Influence of nutrition on the effectiveness of superovulation programmes in ewes: effect on oocyte quality and post-fertilization development. Reproduction, 125, pp. 543–553.

Maia, A.L.R.S., Brandao, F.Z., Souza-Fabjan, J.M.G., Veiga, M.O., Balaro, M.F.A., Siqueira, L.G.B., Facó O. and Fonseca J.F., 2018. Hydrometra in dairy goats: Ultrasonic variables and therapeutic protocols evaluated during the reproductive season. Animal Reproduction Science, 197, pp. 203-211.

Ortega-Pacheco, A., Torres-Acosta, J.F.J., Aguilar-Caballero A.J. and Ramón-Ugalde, J.P., 2002. Fertilidad y fallas reproductivas en un rebaño de cabras criollas en el trópico subhúmedo, sincronizadas con esponjas vaginales. Revista Biomédica, 13, pp. 179-184.

Ott, R.S., Nelson, D.R. and Hixon, J.E., 1980. Effect of presence of the male on initiation of estrous cycle activity of goats. Theriogenology, 13, pp. 183-190.

Pellicer-Rubio, M.T., Leboeuf, B., Bernelas, D., Forgerit, Y., Pougnard, J.L., Bonne?, J.L., Senty, E. and Chemineau, P., 2007. Highly synchronous and fertile reproductive activity induced by the male effect during deep anoestrus in lactating goats subjected to treatment with artificially long days followed by a natural photoperiod. Animal Reproduction Science, 98, pp. 241-58.

Shelton, M., 1960. In?uence of the presence of a male goat on the initiation of oestrous cycling and ovulation of Angora does. Journal of Animal Science, 19, pp. 368-375.

Sosa, C., Abecia, J.A., Forcada, F., Vinoles, C., Tasende, C., Valares, J.A., Palacin, I., Martin, G.B. and Meikle, A., 2006. Effect of undernutrition on uterine progesterone and oestrogen receptors and on endocrine profiles during the ovine oestrous cycle. Reprodution, Fertility and Development, 18, 447–458.

System Statistics 2009. Cranes Software International Ltd., San Jose, CA, USA.

Walkden-Brown, S.W., Restall, B.J., Scaramuzzi, R.J., Martin, G.B. and Blackberry, M.A., 1997. Seasonality in male Australian cashmere goats: long term effects of castration and testosterone or oestradiol treatment on changes in LH, FSH, and prolactin concentrations, and body growth. Small Ruminant Research, 26, pp. 239-252.

Walkden-Brown, S.W., Martin, G.B., Restall, B.J., 1999. Role of male–female interaction in regulating reproduction in sheep and goats. Journal of Reproduction and Fertility Supplement, 52, pp. 243–257.

Wittek, T., Richter, A., Erices J. and Elze, K., 1997. Incidence, diagnosis, therapy and subsequent fertility in goats with hydrometra. Tierarztl Prax Ausg G Grosstiere Nutztiere, 25, pp. 576-582.

Zarazaga, L.A., Gatica, M.C., Hernández, H., Chemineau, P., Delgadillo, J.A. and Guzmán, J.L., 2019. Photoperiod-treated bucks are equal to melatonin-treated bucks for inducing reproductive behaviour and physiological functions via the “male effect” in Mediterranean goats. Animal Reproduction Science, 202, pp. 58-64.



Copyright (c) 2023 Jose Alberto Delgadillo

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.