Reproductive response of synchronized and extensively grazed Blackbelly ewes during the summer in the tropics

José Luis Ponce-Covarrubias; Ethel Caterina García y González; Jacinto Efrén Ramírez-Bribiesca; Blanca Celia Pineda-Burgos

doi:10.31893/jabb.23001

Keywords:

estrous cycle

reproductive behavior

temperature and humidity index

weight and body condition

Abstract

The present experiment aimed to evaluate the reproductive response of Blackbelly ewes synchronized with low doses of eCG during the summer in a tropical climate. Sixty multiparous hair ewes were divided into three groups (20 ewes/group): control group (CG; 0 IU of eCG), treated group 1 (TG-1; 140 IU of eCG) and treated group 2 (TG-2; 300 IU of eCG). The study found that the three groups of ewes showed differences in their reproductive behavior (P < 0.01). Indeed, all the ewes in the TG-1 and TG-2 groups presented a higher response to estrus than the CG (P < 0.01). In the same way, TG-1 and TG-2 had an onset to estrus in less time (P < 0.01). On the other hand, prolificacy was also higher in TG-1 and TG-2 (P < 0.05). Likewise, ewes from TG-1 and TG-2 had more lambs than those from CG (P < 0.05). On the other hand, the variables of fertility and gestation length were similar regardless of the group of ewes (P > 0.05). It´s concluded that the ewes treated with eCG presented good reproductive behavior, and the majority did so in the first 24 to 36 h after removing the intravaginal device.
References
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2. Ali A (2007) Effect of time of eCG administration on follicular response and reproductive performance of FGA-treated Ossimi ewes. Small Ruminant Research 72:33–37.
3. Ball GF, Balthazart J (2008) How useful is the appetitive and consummatory distinction for our understanding of the neuroendocrine control of sexual behavior? Hormones and Behavior 53:307–318.
4. Barragán-Sierra A, Avendaño-Reyes L, Hernández-Rivera JA, Vicente-Pérez R, Correa-Calderón A, Mellado M, Meza-Herrera CA, Macías-Cruz U (2021) Termorregulación y respuestas reproductivas de carneros bajo estrés por calor. Revisión Revista Mexicana de Ciencias Pecuarias 12(3):910–931.
5. Ben Säid S, Lomet D, Chesneau D, Lardic L, Canepa S, Guillaume D, Briant C, Frabre-Nys C, Caraty A (2007) Differential estradiol requirement for the induction of estrus behavior and the luteinizing hormone surge in two breeds of sheep. Biology of Reproduction 76:673–680.
6. Blissitt MJ, Bland KP, Cottrell DF (1990) Discrimination between odors of fresh estrous and non-estrous ewe urine by rams. Applied Animal Behaviour Science 25:51-59.
7. Calderón-Leyva G, Meza-Herrera CA, Rodríguez-Martínez R, Angel-García O, Rivas-Muñoz R, Delgado-Bermejo JV, Véliz-Deras FG (2018) Influence of sexual behavior of Dorper rams treated with glutamate and/or testosterone on reproductive performance of anovulatory ewes. Theriogenology 106(15):79–86.
8. CNOG, Confederación Nacional de Organizaciones Ganaderas. 2012. Estudios Económicos. Indicadores Económicos. Boletín Económico 21. [Online]. Available in: http://www.cnog.org.mx/_documentos/7534_BoletinEconomico021.pdf (retrieved March 24, 2022).
9. FAO, Food Alimentation Organization of the United Nations. 2014. Consumo de carne. Departamento de Agricultura y Protección del Consumidor. Producción y Sanidad Animal. Noviembre Consumo per cápita de carne de ovino en México (Adapted of SIAP, 2014). 25, 2014. [Online]. Available in: http://www.fao.org/ag/againfo/themes/es/meat/background.html (retrieved March 24, 2022).
10. FAOSTAT, Statistics for Food Alimentation Organization of the United Nations. 2015. Estadísticas de la Ganadería Mundial. [Online]. Available in: http://faostat3.fao.org/download/Q/*/E (retrieved March 24, 2022).
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12. García y González EC, Macías-Cruz U, Avendaño-Reyes L, Velázquez-Morales JV, Vicente-Pérez R, Zúñiga-García A, Ponce JL (2018) Parity of the Dorper sheep does not influence the reproductive and productive response when they are synchronized with an “ultra-short” protocol. Open Access Journal of Science 2(3):193–196.
13. García E (1987) Modificaciones al sistema de clasificación climática de Koeppen. Editorial Universidad Nacional Autónoma de México, México, 12-13 p. (retrieved April 12, 2022). https://www.igg.unam.mx/geoigg/biblioteca/archivos/memoria/20190917100949.pdf
14. Gastélum-Delgado MA, Avendaño-Reyes L, Álvarez-Valenzuela FD, Correa-Calderón A, Meza-Herrera CA, Mellado-Bosque M, Macías-Cruz U (2015) Comportamiento de estro circanual en ovejas Pelibuey bajo condiciones áridas del Noroeste de México. Revista Mexicana de Ciencias Pecuarias 6(1), 109-118.
15. Giriboni J, Lacuesta L, Ungerfeld R (2017) Continuous contact with females in estrus throughout the year enhances testicular activity and improves seminal traits of male goats. Theriogenology 87:284-289.
16. González-Tavizón A, Meza-Herrera CA, Arellano-Rodríguez G, Mellado M, Contreras-Villarreal V, Angel-García O, Arévalo JR, Véliz-Deras FG (2022) Effect of Dorper rams´social-sexual hierarchy on their sexual behavior and capacity to induce estrus in ewes. Agriculture 12:391.
17. Grimaldo-Viesca E, Duarte-Moreno G, Hernández-Hernández H, Flores-Cabrera JA, Delgadillo-Sánchez JA, Vielma-Sifuentes J (2020) La presencia de cabras en estro mejora la actividad sexual en los machos en reposo sexual estacional. Agrociencia 54:31–42.
18. Habeeb AA, Gad AE, Atta MA (2018) Temperature-humidity indices as indicators to heat stress of climatic conditions with relation to production and reproduction of farm animals. International Journal of Biotechnology and Recent Advances 1(1): 35-50.
19. Hamilton TR, Mendes, CM, de Castro LS, de Assis PM, Siqueira AF, de Carvalho J, Demarchi-Goissis M, Muiño-Blanco T, Cebrián-Pérez JA, Nichi M, Visitin JA, Ortiz Da´Avila-A (2016) Evaluation of lasting effects of heat stress on sperm profile and oxidative status of ram semen and epididymal sperm. Oxid Med Cell Longev 1–12.
20. Hernández-Ruiz PE, García y González EC, Pineda-Burgos BC, Flores-López E, Valencia-Franco E, Carmona-Victoria M, Velázquez-Morales JV, Ponce-Covarrubias JL (2021) Reproductive evaluation of bucks (Capra hircus L.) with usual management in herds from Benito Juarez, Guerrero, Mexico. Agro Productividad 14(3):81–86.
21. Kelly CF, Bond TE (1971) Bioclimatic factors and their measurements. Page 7 in A Guide to Environmental Research in Animals. Natl. Acad. Sci., Washington, DC.
22. Kermani MH, Kohram H, Zareh SA, Saberifar T (2012) Ovarian response and pregnancy rate following different doses of eCG treatment in Chall ewes. Small Ruminant Research 102:63–67.
23. Laporte-Broux B, Roussel S, Ponter AA, Perault J, Chavatte-Palmer P, Duvaux-Ponter C (2011) Short-term effects of maternal feed restriction during pregnancy on goat kid morphology, metabolism, and behavior. Journal of Animal Science 89(7):2154 –2163.
24. López-García S, Sánchez-Torres MT, Cordero-Mora JL, Figueroa-Velasco JL, Martínez-Aispuro JA, García-Cué JL, Martínez-Cruz I, Cárdenas-León M (2021) Estrous synchronization in sheep with reused progesterone divices and eCG. Revista Brasileira de Zootecnia 50:e20200176.
25. Luther JS, Grazul-Bilska AT, Kirsch JD, Weigl RM, Kraft C, Navanukraw C, Pant D, Reynolds LP, Redmer DA (2007) The effect of GnRH, eCG and progestin type on estrous synchronization following laparoscopic AI in ewes. Small Ruminant Research 72:227–231.
26. Macías-Cruz U, Álvarez-Valenzuela FD, Correa-Calderón A, Díaz-Molina R, Mellado M, Meza-Herrera C, Avendaño-Reyes L (2013) Thermoregulation of nutrient-restricted hair ewes subjected to heat stress during late pregnancy. Journal Thermal Biology 38:1–9.
27. Macías-Cruz U, Álvarez-Valenzuela FD, Correa-Calderón A, Molina-Ramírez L, González-Reyna A, Soto-Navarro S, Avendaño-Reyes L (2009) Pelibuey ewe productivity and subsequent pre-weaning lamb performance using hair-sheep breed under a confinement system. Journal Appled Animal Research 36:255–260.
28. Macías-Cruz U, Álvarez-Valenzuela FD, Olguín-Arredondo HA, Molina-Ramírez L, Avendaño-Reyes L (2012) Ovejas Pelibuey sincronizadas con progestágenos y apareadas con machos de razas Dorper y Katahdin bajo condiciones estabuladas: producción de la oveja y crecimiento de los corderos durante el período predestete. Archivos de Medicina Veterinaria 44:29–37.
29. Macías-Cruz U, Sánchez-Estrada TJ, Gastelum-Delgado MA, Avendaño-Reyes L, Correa-Calderón A, Álvarez-Valenzuela FD, Díaz-Molina R, Meza-Herrera CA, Mellado M (2015) Actividad reproductiva estacional de ovejas Pelibuey bajo condiciones áridas de México. Archivos de Medicina Veterinaria 47:381–386.
30. Marai IFM, El-Darawany AA, Fadiel A, Abdel-Hafez MAM (2007) Physiological traits as affected by heat stress in sheep - A review. Small Ruminant Research, 71(1-3):1–12.
31. Martin GB, Kadokawa H (2006) «Clean, green and ethical» animal production. Case study: reproductive efficiency in small ruminants. Journal Reproduction Development 52:145–152.
32. NAM-National Academy of Medicine. Guide for the Care and Use of Laboratory Animals. Co-Produced by the National Academy of Medicine–Mexico and the Association for Assessment and Accreditation of Laboratory Animal Care International, 1st ed.; Harlan: Mexico City, Mexico, 2002. https://www.nap.edu/read/5140/chapter/1
33. Ponce JL, Velázquez H, Duarte G, Bedos M, Hernández H, Keller M, Chemineau P, Delgadillo JA (2014) Reducing exposure to long days from 75 to 30 days of extra-ligth treatment does not decrease the capacity of male gots to stimulate ovulatory activity in seasonally anovulatory females. Domestic Animal Endocrinology 48:119–125.
34. Quintero-Elisea JA, Macías-Cruz U, Álvarez-Valenzuela FD, Correa-Calderón A, González-Reyna A, Lucero-Magaña FA, Soto-Navarro S, Avendaño-Reyes L (2011) The effects of time and dose of pregnant mare serum gonadotropin (PMSG) on reproductive efficiency in hair sheep ewes. Tropical Animal Health Production 43(8):1567–1673.
35. Romano JE, Rodas E, Ferreira A, Lago I, Benech A (1996) Effects of progestagen PMSG and artificial insemination time on fertility and prolificacy in Corriedale ewes. Small Ruminant Research 23:157–162.
36. Ruiz-Ortega M, García y González EC, Hernández-Ruiz PE, Pineda-Burgos BC, Sandoval-Torres MA, Velázquez-Morales JV, Rodríguez-Castillo JdC, Rodríguez-Castañeda EL, Robles-Robles JM, Ponce-Covarrubias JL (2022) Thermorregulatory response of Blackbelly adult ewes and female lambs during the summer under Tropical conditions in southern Mexico. Animals 12:1960.
37. Rosado J, Silva E, Galina MA (1998) Reproductive management of hair sheep with progesterone and gonadotropins in the tropics. Small Ruminant Research 27: 237–242.
38. SAS/STAT 2004. User’s Guide Statistics Released 9.1, 2nd Ed. SAS Institute, Inc. Cary, NC, USA. https://support.sas.com/documentation/onlinedoc/91pdf/sasdoc_91/stat_ug_7313.pdfSIAP -
39. SIAP. Servicio de información agroalimentaria y pesquera (2016) [Online]. Available in: http://infosiap.siap.gob.mx/anpecuario_siap_gb_1/indexnal_gb.html (retrieved April 19, 2022).
40. SIAP; Servicio de información agroalimentaria y pesquera (2018) Población caprina ganadera 2009 - 2018. [Online]. Available in: https://www.gob.mx/cms/uploads/attachment/file/516350/Inventario_2018_Caprino_pdf (retrieved April 19, 2022).
41. Vicente-Pérez R, Macías-Cruz U, Avendaño-Reyes L, Correa-Calderón A, López-Baca MA, Lara-Rivera AL (2020) Impacto del estrés por calor en la producción de ovinos de pelo. Revista Mexicana de Ciencias Pecuarias 11:205–222.

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

How to cite

Ponce-Covarrubias, J. L., García y González, E. C., Ramírez-Bribiesca, J. E., & Pineda-Burgos, B. C. (2022). Reproductive response of synchronized and extensively grazed Blackbelly ewes during the summer in the tropics. Journal of Animal Behaviour and Biometeorology, 11(1), e2023001. https://doi.org/10.31893/jabb.23001

[1] Alexandratos N, Bruinsma J (2012) World agriculture towards 2030/2050: the 2012 revision. ESA Working paper No. 12-03. Rome, FAO. [Online]. https://www.fao.org/3/ap106e/ap106e.pdf

[2] Ali A (2007) Effect of time of eCG administration on follicular response and reproductive performance of FGA-treated Ossimi ewes. Small Ruminant Research 72:33–37.

[3] Ball GF, Balthazart J (2008) How useful is the appetitive and consummatory distinction for our understanding of the neuroendocrine control of sexual behavior? Hormones and Behavior 53:307–318.

[4] Barragán-Sierra A, Avendaño-Reyes L, Hernández-Rivera JA, Vicente-Pérez R, Correa-Calderón A, Mellado M, Meza-Herrera CA, Macías-Cruz U (2021) Termorregulación y respuestas reproductivas de carneros bajo estrés por calor. Revisión Revista Mexicana de Ciencias Pecuarias 12(3):910–931.

[5] Ben Säid S, Lomet D, Chesneau D, Lardic L, Canepa S, Guillaume D, Briant C, Frabre-Nys C, Caraty A (2007) Differential estradiol requirement for the induction of estrus behavior and the luteinizing hormone surge in two breeds of sheep. Biology of Reproduction 76:673–680.

[6] Blissitt MJ, Bland KP, Cottrell DF (1990) Discrimination between odors of fresh estrous and non-estrous ewe urine by rams. Applied Animal Behaviour Science 25:51-59.

[7] Calderón-Leyva G, Meza-Herrera CA, Rodríguez-Martínez R, Angel-García O, Rivas-Muñoz R, Delgado-Bermejo JV, Véliz-Deras FG (2018) Influence of sexual behavior of Dorper rams treated with glutamate and/or testosterone on reproductive performance of anovulatory ewes. Theriogenology 106(15):79–86.

[8] CNOG, Confederación Nacional de Organizaciones Ganaderas. 2012. Estudios Económicos. Indicadores Económicos. Boletín Económico 21. [Online]. Available in: http://www.cnog.org.mx/_documentos/7534_BoletinEconomico021.pdf (retrieved March 24, 2022).

[9] FAO, Food Alimentation Organization of the United Nations. 2014. Consumo de carne. Departamento de Agricultura y Protección del Consumidor. Producción y Sanidad Animal. Noviembre Consumo per cápita de carne de ovino en México (Adapted of SIAP, 2014). 25, 2014. [Online]. Available in: http://www.fao.org/ag/againfo/themes/es/meat/background.html (retrieved March 24, 2022).

[10] FAOSTAT, Statistics for Food Alimentation Organization of the United Nations. 2015. Estadísticas de la Ganadería Mundial. [Online]. Available in: http://faostat3.fao.org/download/Q/*/E (retrieved March 24, 2022).

[11] FASS. Guide for the Care and Use of Agricultural Animals in Agricultural Research and Teaching, 3rd ed.; Federation Animal Science Society: Champaing, IL, USA, 2010; p. 177. [Online]. https://www.fass.org/images/science-policy/Ag_Guide_3rd_ed.pdf

[12] García y González EC, Macías-Cruz U, Avendaño-Reyes L, Velázquez-Morales JV, Vicente-Pérez R, Zúñiga-García A, Ponce JL (2018) Parity of the Dorper sheep does not influence the reproductive and productive response when they are synchronized with an “ultra-short” protocol. Open Access Journal of Science 2(3):193–196.

[13] García E (1987) Modificaciones al sistema de clasificación climática de Koeppen. Editorial Universidad Nacional Autónoma de México, México, 12-13 p. (retrieved April 12, 2022). https://www.igg.unam.mx/geoigg/biblioteca/archivos/memoria/20190917100949.pdf

[14] Gastélum-Delgado MA, Avendaño-Reyes L, Álvarez-Valenzuela FD, Correa-Calderón A, Meza-Herrera CA, Mellado-Bosque M, Macías-Cruz U (2015) Comportamiento de estro circanual en ovejas Pelibuey bajo condiciones áridas del Noroeste de México. Revista Mexicana de Ciencias Pecuarias 6(1), 109-118.

[15] Giriboni J, Lacuesta L, Ungerfeld R (2017) Continuous contact with females in estrus throughout the year enhances testicular activity and improves seminal traits of male goats. Theriogenology 87:284-289.

[16] González-Tavizón A, Meza-Herrera CA, Arellano-Rodríguez G, Mellado M, Contreras-Villarreal V, Angel-García O, Arévalo JR, Véliz-Deras FG (2022) Effect of Dorper rams´social-sexual hierarchy on their sexual behavior and capacity to induce estrus in ewes. Agriculture 12:391.

[17] Grimaldo-Viesca E, Duarte-Moreno G, Hernández-Hernández H, Flores-Cabrera JA, Delgadillo-Sánchez JA, Vielma-Sifuentes J (2020) La presencia de cabras en estro mejora la actividad sexual en los machos en reposo sexual estacional. Agrociencia 54:31–42.

[18] Habeeb AA, Gad AE, Atta MA (2018) Temperature-humidity indices as indicators to heat stress of climatic conditions with relation to production and reproduction of farm animals. International Journal of Biotechnology and Recent Advances 1(1): 35-50.

[19] Hamilton TR, Mendes, CM, de Castro LS, de Assis PM, Siqueira AF, de Carvalho J, Demarchi-Goissis M, Muiño-Blanco T, Cebrián-Pérez JA, Nichi M, Visitin JA, Ortiz Da´Avila-A (2016) Evaluation of lasting effects of heat stress on sperm profile and oxidative status of ram semen and epididymal sperm. Oxid Med Cell Longev 1–12.

[20] Hernández-Ruiz PE, García y González EC, Pineda-Burgos BC, Flores-López E, Valencia-Franco E, Carmona-Victoria M, Velázquez-Morales JV, Ponce-Covarrubias JL (2021) Reproductive evaluation of bucks (Capra hircus L.) with usual management in herds from Benito Juarez, Guerrero, Mexico. Agro Productividad 14(3):81–86.

[21] Kelly CF, Bond TE (1971) Bioclimatic factors and their measurements. Page 7 in A Guide to Environmental Research in Animals. Natl. Acad. Sci., Washington, DC.

[22] Kermani MH, Kohram H, Zareh SA, Saberifar T (2012) Ovarian response and pregnancy rate following different doses of eCG treatment in Chall ewes. Small Ruminant Research 102:63–67.

[23] Laporte-Broux B, Roussel S, Ponter AA, Perault J, Chavatte-Palmer P, Duvaux-Ponter C (2011) Short-term effects of maternal feed restriction during pregnancy on goat kid morphology, metabolism, and behavior. Journal of Animal Science 89(7):2154 –2163.

[24] López-García S, Sánchez-Torres MT, Cordero-Mora JL, Figueroa-Velasco JL, Martínez-Aispuro JA, García-Cué JL, Martínez-Cruz I, Cárdenas-León M (2021) Estrous synchronization in sheep with reused progesterone divices and eCG. Revista Brasileira de Zootecnia 50:e20200176.

[25] Luther JS, Grazul-Bilska AT, Kirsch JD, Weigl RM, Kraft C, Navanukraw C, Pant D, Reynolds LP, Redmer DA (2007) The effect of GnRH, eCG and progestin type on estrous synchronization following laparoscopic AI in ewes. Small Ruminant Research 72:227–231.

[26] Macías-Cruz U, Álvarez-Valenzuela FD, Correa-Calderón A, Díaz-Molina R, Mellado M, Meza-Herrera C, Avendaño-Reyes L (2013) Thermoregulation of nutrient-restricted hair ewes subjected to heat stress during late pregnancy. Journal Thermal Biology 38:1–9.

[27] Macías-Cruz U, Álvarez-Valenzuela FD, Correa-Calderón A, Molina-Ramírez L, González-Reyna A, Soto-Navarro S, Avendaño-Reyes L (2009) Pelibuey ewe productivity and subsequent pre-weaning lamb performance using hair-sheep breed under a confinement system. Journal Appled Animal Research 36:255–260.

[28] Macías-Cruz U, Álvarez-Valenzuela FD, Olguín-Arredondo HA, Molina-Ramírez L, Avendaño-Reyes L (2012) Ovejas Pelibuey sincronizadas con progestágenos y apareadas con machos de razas Dorper y Katahdin bajo condiciones estabuladas: producción de la oveja y crecimiento de los corderos durante el período predestete. Archivos de Medicina Veterinaria 44:29–37.

[29] Macías-Cruz U, Sánchez-Estrada TJ, Gastelum-Delgado MA, Avendaño-Reyes L, Correa-Calderón A, Álvarez-Valenzuela FD, Díaz-Molina R, Meza-Herrera CA, Mellado M (2015) Actividad reproductiva estacional de ovejas Pelibuey bajo condiciones áridas de México. Archivos de Medicina Veterinaria 47:381–386.

[30] Marai IFM, El-Darawany AA, Fadiel A, Abdel-Hafez MAM (2007) Physiological traits as affected by heat stress in sheep - A review. Small Ruminant Research, 71(1-3):1–12.

[31] Martin GB, Kadokawa H (2006) «Clean, green and ethical» animal production. Case study: reproductive efficiency in small ruminants. Journal Reproduction Development 52:145–152.

[32] NAM-National Academy of Medicine. Guide for the Care and Use of Laboratory Animals. Co-Produced by the National Academy of Medicine–Mexico and the Association for Assessment and Accreditation of Laboratory Animal Care International, 1st ed.; Harlan: Mexico City, Mexico, 2002. https://www.nap.edu/read/5140/chapter/1

[33] Ponce JL, Velázquez H, Duarte G, Bedos M, Hernández H, Keller M, Chemineau P, Delgadillo JA (2014) Reducing exposure to long days from 75 to 30 days of extra-ligth treatment does not decrease the capacity of male gots to stimulate ovulatory activity in seasonally anovulatory females. Domestic Animal Endocrinology 48:119–125.

[34] Quintero-Elisea JA, Macías-Cruz U, Álvarez-Valenzuela FD, Correa-Calderón A, González-Reyna A, Lucero-Magaña FA, Soto-Navarro S, Avendaño-Reyes L (2011) The effects of time and dose of pregnant mare serum gonadotropin (PMSG) on reproductive efficiency in hair sheep ewes. Tropical Animal Health Production 43(8):1567–1673.

[35] Romano JE, Rodas E, Ferreira A, Lago I, Benech A (1996) Effects of progestagen PMSG and artificial insemination time on fertility and prolificacy in Corriedale ewes. Small Ruminant Research 23:157–162.

[36] Ruiz-Ortega M, García y González EC, Hernández-Ruiz PE, Pineda-Burgos BC, Sandoval-Torres MA, Velázquez-Morales JV, Rodríguez-Castillo JdC, Rodríguez-Castañeda EL, Robles-Robles JM, Ponce-Covarrubias JL (2022) Thermorregulatory response of Blackbelly adult ewes and female lambs during the summer under Tropical conditions in southern Mexico. Animals 12:1960.

[37] Rosado J, Silva E, Galina MA (1998) Reproductive management of hair sheep with progesterone and gonadotropins in the tropics. Small Ruminant Research 27: 237–242.

[38] SAS/STAT 2004. User’s Guide Statistics Released 9.1, 2nd Ed. SAS Institute, Inc. Cary, NC, USA. https://support.sas.com/documentation/onlinedoc/91pdf/sasdoc_91/stat_ug_7313.pdfSIAP -

[39] SIAP. Servicio de información agroalimentaria y pesquera (2016) [Online]. Available in: http://infosiap.siap.gob.mx/anpecuario_siap_gb_1/indexnal_gb.html (retrieved April 19, 2022).

[40] SIAP; Servicio de información agroalimentaria y pesquera (2018) Población caprina ganadera 2009 - 2018. [Online]. Available in: https://www.gob.mx/cms/uploads/attachment/file/516350/Inventario_2018_Caprino_pdf (retrieved April 19, 2022).

[41] Vicente-Pérez R, Macías-Cruz U, Avendaño-Reyes L, Correa-Calderón A, López-Baca MA, Lara-Rivera AL (2020) Impacto del estrés por calor en la producción de ovinos de pelo. Revista Mexicana de Ciencias Pecuarias 11:205–222.

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References

How to cite