Sales J N S, Dias L M K, Viveiros A T M, Pereira M N, Souza J C
Department of Animal Science, Universidade Federal de Lavras, Lavras-MG, Brazil.
Anim Reprod Sci. 2008 Jun;106(1-2):77-89. doi: 10.1016/j.anireprosci.2007.04.001. Epub 2007 Apr 7.
The hypothesis was that the intramuscular injection (i.m.) of beta-carotene associated to tocopherol improves cow (n=86) and heifer (n=91) embryo production and quality. Time of estrus was synchronized in animals with an ear implant with 3 mg of norgestomet associated with an i.m. injection of 6 mg of norgestomet and 10mg of estradiol valerate (CRESTAR, Intervert International B.V., Boxmeer, Holland) and superovulated by 8 i.m. FSH/LHp injections (400 IU-heifers and 500 IU-cows) in decreasing concentrations at 12h intervals. Animals were inseminated 12 and 24h after observed onset of estrus and embryos recovered 7 days later. Animals were randomly allocated to one of three treatments: (1) vegetable oil vehicle (control), (2) 800 mg of beta-carotene and 500 mg of tocopherol (T800) and (3) 1200 mg of beta-carotene and 750 mg of tocopherol (T1200). Supplemental injections were given at the day norgestomet implants were inserted and at first superovulatory injection. An index (Embryo Quality Index or EQI) was proposed to more precisely evaluate embryo quality (excellent1 + good2 + regular3 + poor4 + degenerate5 + unfertilized ova5)/total. There was an interaction between physiological stage (heifer or cow) and treatment on EQI (P=0.01) and on the proportion of viable embryos (P=0.03), where both variables were improved in T1200 cows, but not in heifers. The average EQI for heifers and cows in control, T800 and T1200 were 2.6+/-0.3 and 3.6+/-0.3; 2.5+/-0.3 and 3.6+/-0.3; 2.9+/-0.3 and 2.7+/-0.3, respectively. The average total number of viable embryos was greater (P=0.01) in supplemented cows (3.5+/-1.1; 5.4+/-1.4 and 7.5+/-1.2 in control, T800 and T1200, respectively), but less (P=0.01) in heifers (7.5+/-1.2; 5.6+/-1.2 and 4.0+/-1.1 in control, T800 and T1200, respectively). Supplementation injections of beta-carotene associated to tocopherol improved embryo quality in superovulated Holstein cows, in the present experimental conditions and may be advantageous in similar embryo production systems. However, at dosages applied in the present experiment, this treatment should not be recommended for nulliparous heifers.
研究假设为，肌肉注射（i.m.）与生育酚相关的β-胡萝卜素可提高奶牛（n = 86）和小母牛（n = 91）的胚胎产量及质量。使用含3毫克诺孕美特的耳部植入物并配合肌肉注射6毫克诺孕美特和10毫克戊酸雌二醇（CRESTAR，Intervert International B.V.，荷兰博克斯梅尔）使动物发情时间同步，并通过每隔12小时进行8次肌肉注射促卵泡素/促黄体素（小母牛400国际单位，奶牛500国际单位）进行超数排卵。在观察到发情开始后12小时和24小时对动物进行授精，并在7天后回收胚胎。动物被随机分配到三种处理之一：（1）植物油载体（对照），（2）800毫克β-胡萝卜素和500毫克生育酚（T800），（3）1200毫克β-胡萝卜素和750毫克生育酚（T1200）。在插入诺孕美特植入物当天和首次超数排卵注射时进行补充注射。提出了一个指数（胚胎质量指数或EQI）以更精确地评估胚胎质量（优秀1 + 良好2 + 一般3 + 差4 + 退化5 + 未受精卵5）/总数。生理阶段（小母牛或奶牛）与处理在EQI（P = 0.01）和存活胚胎比例（P = 0.03）上存在交互作用，其中T1200组的奶牛这两个变量均得到改善，但小母牛未改善。对照组、T800组和T1200组小母牛和奶牛的平均EQI分别为2.6±0.3和3.6±0.3；2.5±0.3和3.6±0.3；2.9±0.3和2.7±0.3。补充组奶牛的平均存活胚胎总数更多（P = 0.01）（对照组、T800组和T1200组分别为3.5±1.1、5.4±1.4和7.5±1.2），但小母牛更少（P = 0.01）（对照组、T800组和T1200组分别为7.5±1.2、5.6±1.2和4.0±1.1）。在本实验条件下，与生育酚相关的β-胡萝卜素补充注射可提高超数排卵的荷斯坦奶牛的胚胎质量，在类似的胚胎生产系统中可能具有优势。然而，在本实验所应用的剂量下，这种处理方法不推荐用于未产小母牛。
