Table_2_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.

在牛群中，经玻璃化/复温（V/W）与冷冻/解冻（F/T）处理以及在体外生产（IVP）的胚胎，其生理状态及存活率与新鲜胚胎存在差异。本研究旨在分析胚胎冷冻保存技术对后代的影响。在培养至第6天时，使用白蛋白以及含或不含0.1%血清的IVP胚胎，随后在无蛋白的单培养条件下继续培养，并于第7天将这些胚胎转移至受体母牛体内，以F/T、V/W或新鲜状态进行移植，分别得到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）、摄入后（第15天）以及第30天进行血液分析。在第0天，来自V/W和F/T胚胎的小牛表现出肌酐和毛细血管充盈时间（CRT）增加，心跳减少。与V/W胚胎的小牛相比，来自F/T胚胎的小牛的动脉血二氧化碳分压（PCO2）、血红蛋白和红细胞压积较低，而V/W胚胎则导致小牛的钠离子（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，表明小牛之间的适应性能力相似。然而，在摄入初乳后，V/W胚胎的小牛的PCO2并未降低。培养液中的血清导致小牛体温、CRT、碳酸氢盐（HCO3-）、碱剩余（BE）、总二氧化碳（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天时，腹泻的出现影响了数值，主要见于V/W胚胎的小牛（即TCO2、HCO3-和BE的值降低；葡萄糖、阴离子间隙和乳酸值增加），尽管其临床并发症与来自新鲜和F/T胚胎的小牛相比并未加剧。腹泻影响了所有组别的小牛的PCO2和Na+。胚胎冷冻保存及/或培养，导致小牛产生代谢差异，包括对蛋白质和酸碱代谢的影响。