Carnagey K M, Huff-Lonergan E J, Trenkle A, Wertz-Lutz A E, Horst R L, Beitz D C
Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
J Anim Sci. 2008 Jul;86(7):1649-57. doi: 10.2527/jas.2007-0502. Epub 2008 Mar 14.
The objective of this trial was to determine whether a single bolus of 25-hydroxyvitamin D(3) (25-OH D(3)), vitamin E, or a combination of the 2 would improve the tenderness of steaks from the LM of beef heifers. Forty-eight Angus crossbred heifers were allotted randomly to 8 pens. Six heifers were in each pen, and there were 2 pens per treatment. The 4 treatments included control (no 25-OH D(3) or vitamin E); 25-OH D(3) (500 mg of 25-OH D(3) administered as a one-time oral bolus 7 d before slaughter); vitamin E (1,000 IU of vitamin E administered daily as a top-dress for 104 d before slaughter); or combination (500 mg of 25-OH D(3) administered as a one-time oral bolus 7 d before slaughter and 1,000 IU of vitamin E administered daily as a top-dress for 104 d before slaughter). Blood samples were obtained on the day that heifers were allotted to treatments, on the day 25-OH D(3) was administered, and on the day before slaughter. Plasma calcium concentration was increased when 25-OH D(3) was administered with or without vitamin E (P < 0.007). In LM, calcium concentration tended to increase (P = 0.10) when 25-OH D(3) was administered alone but not when 25-OH D(3) was administered with vitamin E. Concentrations of 25-OH D(3) and 1,25-dihydroxyvitamin D(3) in plasma were increased when 25-OH D(3) was administered with or without vitamin E (P < 0.001). Steaks from heifers treated with 25-OH D(3) or vitamin E, but not both, tended to have lower Warner-Bratzler shear force than steaks in the control group at 14 d postmortem (P = 0.08). Postmortem protein degradation as measured by Western blot of the 30-kDa degradation product of troponin-T was increased with all treatments after 3 d postmortem (P </= 0.07), but not at 7 or 14 d postmortem. Unexpectedly, the use of 500 mg of 25-OH D(3) fed as an oral bolus 7 d before slaughter or 1,000 IU of vitamin E administered daily for 104 d before slaughter alone, but not in combination, effectively decreased Warner-Bratzler shear force.
本试验的目的是确定单次大剂量注射25-羟基维生素D(3)（25-OH D(3)）、维生素E或二者组合是否会改善肉用小母牛腰大肌牛排的嫩度。48头安格斯杂交小母牛被随机分配到8个围栏中。每个围栏中有6头小母牛，每种处理有2个围栏。4种处理包括对照组（不注射25-OH D(3)或维生素E）；25-OH D(3)组（在屠宰前7天一次性口服大剂量注射500 mg 25-OH D(3)）；维生素E组（在屠宰前104天每天在饲料表面添加1000 IU维生素E）；或组合组（在屠宰前7天一次性口服大剂量注射500 mg 25-OH D(3)，并在屠宰前104天每天在饲料表面添加1000 IU维生素E）。在小母牛被分配到各处理组当天、注射25-OH D(3)当天以及屠宰前一天采集血样。单独或联合使用25-OH D(3)时，血浆钙浓度均升高（P < 0.007）。在腰大肌中，单独注射25-OH D(3)时钙浓度有升高趋势（P = 0.10），但联合使用25-OH D(3)和维生素E时则无此现象。单独或联合使用25-OH D(3)时，血浆中25-OH D(3)和1,25-二羟基维生素D(3)的浓度均升高（P < 0.001）。在宰后14天，用25-OH D(3)或维生素E（但不是二者联合）处理的小母牛的牛排，其Warner-Bratzler剪切力往往低于对照组牛排（P = 0.08）。宰后3天，通过肌钙蛋白-T 30-kDa降解产物的蛋白质免疫印迹法测定的宰后蛋白质降解在所有处理组中均增加（P≤0.07），但在宰后7天和14天则未增加。出乎意料的是，在屠宰前7天口服大剂量注射500 mg 25-OH D(3)或在屠宰前104天每天单独使用1000 IU维生素E（而非联合使用）可有效降低Warner-Bratzler剪切力。
