Diniz Jefferson Viana Alves, Satrapa Rafael Augusto, Segabinazzi Lorenzo Garrido T M, Carneiro João Alexandre Matos, Oba Eunice, Papa Federico Ozanam, Dell'Aqua Camila de Paula Freitas, Loureiro Bárbara, Junior José Antonio Dell'Aqua
Programa de Pós-Graduação em Sanidade e Produção Animal Sustentável na Amazônia Ocidental, Universidade Federal do Acre, Rodovia BR 364, km 4, Bloco Laércio Wanderley da Nóbrega, 1º Piso, 69920-900, Rio Branco, Acre - AC, Brazil.
Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista Júlio de Mesquita Filho, Departamento de Reprodução animal e Radiologia Veterinária, Rua Professor Doutor Walter Maurício Correa, S/N, 18618-681, Botucatu, São Paulo - SP, Brazil.
Theriogenology. 2020 Sep 15;154:59-65. doi: 10.1016/j.theriogenology.2020.05.028. Epub 2020 May 22.
This study aimed to evaluate the effect of sodium caseinate added into freezing extender on the sperm parameters of cryopreserved bull semen and in vitro and in vivo fertility. One ejaculate of 30 bulls was used and processed using Botu-Bov (Botupharma, Botucatu, Brazil) with the addition of 20% egg yolk (EY) or 15% egg yolk with 2% sodium caseinate (EY + SC), subsequently submitted to freezing. Semen from both groups were evaluated immediately after thawing (T0) and after thermic stress at 37 °C for 90 min (T90), for sperm kinetics, by CASA method, and plasma membrane integrity (PMI), superoxide (O) concentration and high mitochondrial potential (HMP) by flow cytometry. In vitro fertilization (IVF) was performed to assess embryo cleavage rate on day 3, and blastocyst rate on day 8. The in vivo fertility test was performed using fixed-time artificial insemination (FTAI). In sperm evaluation, trajectory velocity, linear velocity, curvilinear velocity, and lateral head movement were higher (P < 0.05) in EY + SC at T0. At T90, while rectilinearity and linearity did not differ between EY and EY + SC (P > 0.05), the other parameters evaluated were higher in EY + SC. Similarly, the integrity of the plasma and acrosomal membranes (iPAM) was higher (P < 0.05) at T90 in EY + SC, but did not differ (P > 0.05) between the groups at T0. For O and HMP, the values were lower (P < 0.05) in EY + SC group in both moments; furthermore, EY + SC showed higher cleavage and blastocyst rates in IVF. Likewise, pregnancy rates by FTAI were higher (P < 0.05) in the EY + SC group. In conclusion, the addition of sodium caseinate into freezing extender improves sperm parameters of frozen-thawed bull semen and fertility rates on during in vitro and in vivo tests.
本研究旨在评估在冷冻稀释液中添加酪蛋白酸钠对冷冻保存的公牛精液的精子参数以及体外和体内受精能力的影响。使用30头公牛的一次射精，采用Botu - Bov（Botupharma，Botucatu，巴西）进行处理，添加20%蛋黄（EY）或15%蛋黄与2%酪蛋白酸钠（EY + SC），随后进行冷冻。两组精液在解冻后立即（T0）以及在37°C热应激90分钟后（T90）进行评估，通过CASA方法评估精子活力，通过流式细胞术评估质膜完整性（PMI）、超氧化物（O）浓度和高线粒体电位（HMP）。进行体外受精（IVF）以评估第3天的胚胎分裂率和第8天的囊胚率。体内受精能力测试采用定时人工授精（FTAI）。在精子评估中，T0时EY + SC组的轨迹速度、直线速度、曲线速度和头部侧向运动更高（P < 0.05）。在T90时，虽然EY和EY + SC组之间的直线性和线性没有差异（P > 0.05），但EY + SC组评估的其他参数更高。同样，T90时EY + SC组的质膜和顶体膜完整性（iPAM）更高（P < 0.05），但T0时两组之间没有差异（P > 0.05）。对于O和HMP，两个时间点EY + SC组的值均较低（P < 0.05）；此外，EY + SC组在IVF中显示出更高的分裂率和囊胚率。同样，EY + SC组通过FTAI的妊娠率更高（P < 0.05）。总之，在冷冻稀释液中添加酪蛋白酸钠可改善冻融公牛精液的精子参数以及体外和体内测试的受精率。
