The Revista Brasileira de Zootecnia (RBZ) is a publication dedicated to the broad field of Animal Science. We publish high-quality, original scientific research that spans across diverse areas within the discipline. The scope of RBZ encompasses a wide range of topics, including aquaculture, biometeorology and animal welfare, forage crops and grasslands, animal and forage plants breeding and genetics, animal reproduction, ruminant and non-ruminant nutrition, meat science and muscle biology, precision livestock, and animal production systems and agribusiness.
The Revista Brasileira de Zootecnia (RBZ) is a publication dedicated to the broad field of Animal Science. We publish high-quality, original scientific research that spans across diverse areas within the discipline. The scope of RBZ encompasses a wide range of topics, including aquaculture, biometeorology and animal welfare, forage crops and grasslands, animal and forage plants breeding and genetics, animal reproduction, ruminant and non-ruminant nutrition, meat science and muscle biology, precision livestock, and animal production systems and agribusiness.
The Revista Brasileira de Zootecnia (RBZ) is a publication dedicated to the broad field of Animal Science. We publish high-quality, original scientific research that spans across diverse areas within the discipline. The scope of RBZ encompasses a wide range of topics, including aquaculture, biometeorology and animal welfare, forage crops and grasslands, animal and forage plants breeding and genetics, animal reproduction, ruminant and non-ruminant nutrition, meat science and muscle biology, precision livestock, and animal production systems and agribusiness.
The objective was to investigate the effects of sex-sorting on early fertilization events in ovum pick up (OPU) derived oocytes fertilized in vitro with frozen-thawed sperm at different co-incubation lengths. Eighty-four OPU sessions were carried out in 18 cyclic, dry and non-stimulated Holstein Friesian and German black pied cows. Ovum pick up oocytes were matured in vitro for 24 hours and fertilized with frozen-thawed sex sorted or unsorted sperm from the same ejaculate. Fertilization was achieved by two experimental protocols: 1) short gamete co-incubation length: 4, 8 and 12 hours; and 2) long gamete co-incubation length: 18 and 24 hours. After in vitro fertilization, ova were fixed and stained to identify early fertilization events. Sperm penetration, monospermy, pronuclear formation and syngamy did not differ, whether sexed or unsexed sperm was used. Overall, the findings demonstrate similar fertilizing potential between sex-sorted and unsorted sperm.
Use of sex-sorted and unsorted frozen/thawed sperm and in vitro fertilization events in bovine oocytes derived from ultrasound-guided aspiration
López,Salvador Ruiz and Souza,José Camisão de and González,Javier Zaraza and Sánchez,Aitor De Ondiz and Romero-Aguirregomezcorta,Jon and Carvalho,Rafaela Rodrigues de and Rath,Detlef. Use of sex-sorted and unsorted frozen/thawed sperm and in vitro fertilization events in bovine oocytes derived from ultrasound-guided aspiration. R. Bras. Zootec. [online]. 2013, vol.42, 10, [cited 2026-03-10], pp.721-727. Available from: <https://rbz.org.br/article/use-of-sex-sorted-and-unsorted-frozen-thawed-sperm-and-in-vitro-fertilization-events-in-bovine-oocytes-derived-from-ultrasound-guided-aspiration/>. ISSN 1516-3598. http://doi.org/10.1590/S1516-35982013001000005.
López,Salvador Ruiz; Souza,José Camisão de; González,Javier Zaraza; Sánchez,Aitor De Ondiz; Romero-Aguirregomezcorta,Jon; Carvalho,Rafaela Rodrigues de; Rath,Detlef. Use of sex-sorted and unsorted frozen/thawed sperm and in vitro fertilization events in bovine oocytes derived from ultrasound-guided aspiration. R. Bras. Zootec., v.42, 10, p. 721-727. Oct. 2013. Available from: <https://rbz.org.br/article/use-of-sex-sorted-and-unsorted-frozen-thawed-sperm-and-in-vitro-fertilization-events-in-bovine-oocytes-derived-from-ultrasound-guided-aspiration/>. acess on 10 Mar. 2026. http://doi.org/10.1590/S1516-35982013001000005.
López,Salvador Ruiz, & Souza,José Camisão de, & González,Javier Zaraza, & Sánchez,Aitor De Ondiz, & Romero-Aguirregomezcorta,Jon, & Carvalho,Rafaela Rodrigues de, & Rath,Detlef. (2013). Use of sex-sorted and unsorted frozen/thawed sperm and in vitro fertilization events in bovine oocytes derived from ultrasound-guided aspiration. R. Bras. Zootec., 42(10) , 721-727. http://doi.org/10.1590/S1516-35982013001000005.
LópezSalvador Ruiz, SouzaJosé Camisão de, GonzálezJavier Zaraza, SánchezAitor De Ondiz, Romero-AguirregomezcortaJon, CarvalhoRafaela Rodrigues de, RathDetlef. Use of sex-sorted and unsorted frozen/thawed sperm and in vitro fertilization events in bovine oocytes derived from ultrasound-guided aspiration. R. Bras. Zootec. [Internet]. 2013 Oct [cited 2026 Mar 10]; 42(10): 721-727. Available from: https://rbz.org.br/article/use-of-sex-sorted-and-unsorted-frozen-thawed-sperm-and-in-vitro-fertilization-events-in-bovine-oocytes-derived-from-ultrasound-guided-aspiration/. http://doi.org/10.1590/S1516-35982013001000005.
Figure 3
Ruminal disappearance of ash-free neutral detergent fiber (aNDFom) at 30 h of in situ incubation in corn husks (fresh and ensiled) treated with calcium oxide (CaO) and a mixture of corn heavy steep water and sugarcane molasses (HM).
