Table_3_Fitness of calves born from in vitro-produced fresh and cryopreserved embryos.docx

In cattle, vitrified/warmed (V/W) and frozen/thawed (F/T), in vitro-produced (IVP) embryos, differ in their physiology and survival from fresh embryos. In this study, we analyzed the effects of embryo cryopreservation techniques on the offspring. IVP embryos cultured with albumin and with or without 0.1% serum until Day 6, and thereafter in single culture without protein, were transferred to recipients on Day 7 as F/T, V/W, or fresh, resulting in N = 24, 14, and 13 calves, respectively. Calves were clinically examined at birth, and blood was analyzed before and after colostrum intake (Day 0), and subsequently on Day 15 and Day 30. On Day 0, calves from V/W and F/T embryos showed increased creatinine and capillary refill time (CRT) and reduced heartbeats. Calves from F/T embryos showed lower PCO2, hemoglobin, and packed cell volume than calves from V/W embryos while V/W embryos led to calves with increased Na+ levels. Colostrum effects did not differ between calves from fresh and cryopreserved embryos, indicating similar adaptive ability among calves. However, PCO2 did not decrease in calves from V/W embryos after colostrum intake. Serum in culture led to calves with affected (P < 0.05) temperature, CRT, HCO3-, base excess (BE), TCO2, creatinine, urea, and anion gap. On Day 15, the effects of embryo cryopreservation disappeared among calves. In contrast, Day 30 values were influenced by diarrhea appearance, mainly in calves from V/W embryos (i.e., lower values of TCO2, HCO3-, and BE; and increased glucose, anion gap, and lactate), although with no more clinical compromise than calves from fresh and F/T embryos. Diarrhea affected PCO2 and Na+ in all groups. Embryo cryopreservation, and/or culture, yield metabolically different calves, including effects on protein and acid–base metabolism.

在牛的胚胎中，经过玻璃化/温和加热（V/W）以及冷冻/解冻（F/T）的体外生产（IVP）胚胎与新鲜胚胎在生理特性和存活率方面存在差异。本研究旨在分析胚胎冷冻保存技术对后代的影响。将培养至第6天使用白蛋白以及含或不含0.1%血清的IVP胚胎，之后在无蛋白单培养条件下继续培养，于第7天转移至受体母牛体内，作为F/T、V/W或新鲜胚胎，分别产生N = 24、14和13头小牛。小牛在出生时进行临床检查，并在摄入初乳前（第0天）、之后（第15天和第30天）进行血液分析。在第0天，来自V/W和F/T胚胎的小牛显示出增高的肌酐和毛细血管再充盈时间（CRT），以及降低的心率。与V/W胚胎的小牛相比，F/T胚胎的小牛显示出较低的PCO2、血红蛋白和红细胞压积，而V/W胚胎则导致小牛的Na+水平升高。初乳对来自新鲜和冷冻保存胚胎的小牛的影响无显著差异，表明小牛的适应性能力相似。然而，V/W胚胎的小牛在摄入初乳后PCO2并未降低。培养液中的血清导致小牛体温、CRT、HCO3-、碱过剩（BE）、TCO2、肌酐、尿素和阴离子间隙受到影响（P < 0.05）。在第15天，胚胎冷冻保存对小牛的影响消失。相反，第30天的值受到腹泻出现的影响，主要表现在V/W胚胎的小牛身上（即TCO2、HCO3-和BE的值较低；葡萄糖、阴离子间隙和乳酸的值升高），尽管与来自新鲜和F/T胚胎的小牛相比，临床并发症并未加剧。腹泻影响了所有组别的PCO2和Na+。胚胎冷冻保存以及或培养，导致小牛在代谢上出现差异，包括对蛋白质和酸碱代谢的影响。