Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
J Anim Sci. 2023 Jan 3;101. doi: 10.1093/jas/skad103.
Finishing pigs (N = 224; 28.66 ± 1.90 kg bodyweight) were randomly assigned across 56 pens of either four barrows or gilts, and assigned to one of four diets: control (7,656 IU vitamin A/kg), control supplemented with vitamin A (4.36 ppm, Rovimix A 1000, DSM, Parsippany, NJ, USA), control supplemented with beta-carotene (163.28 ppm, Rovimix β-Carotene 10%, DSM, Parsippany), or control supplemented with oxidized beta-carotene (40 ppm; 10% active ingredient, Avivagen, Ottawa, ON, Canada). Pigs and feeder weights were obtained at the start of the study (d 0), and end of each phase (d 21, 42, and 63). A subset of gilts had a blood sample taken via jugular venipuncture on d 0, a blood sample and vaccinations of Lawsonia intracellularis and porcine circovirus type 2 (PCV2) on d 18, a blood sample and booster vaccination of PCV2 on d 39, a blood sample on day 60, and a final blood sample on day 63. Gilts were euthanized at the end of the study to obtain a liver (entire right lobe) and a jejunum sample (15.24 cm at 10% of length). Additionally, the second and fourth right anterior mammary were collected to assess anterior mammary tissues. Data were analyzed in SAS 9.4 (Statistical Analysis System, Cary, NC) via GLIMMIX procedure. Oxidized beta-carotene supplementation increased (P = 0.02) ADG across phases over vitamin A supplementation, although there were no differences (P = 0.18) in the body weight of pigs. There was no effect (P > 0.05) of diet on plasma or hepatic retinol, IgG or IgM levels, or immune cell presence in developing mammary tissue. Supplemented vitamin A tended (P = 0.05) to increase the mRNA abundance of retinol binding protein in the jejunum, but other mRNA abundance for genes (alcohol dehydrogenase class 1, lecithin retinol acyltransferase phosphatidylcholine-retinol O-acyltransferase, and beta-carotene oxygenase 1) were not affected (P > 0.05) by dietary treatments. A diet by time interaction (P = 0.04) was noted for the circovirus S/P ratio, where vitamin A supplementation had the best ratio compared to other diets. Analyzed titer levels for the circovirus vaccine had an interaction (P < 0.01) for diet by time, where vitamin A supplementation had the highest titer at the end of the study. Thus, pigs supplemented with oxidized beta-carotene had an improved ADG over vitamin A supplemented pigs, but pigs supplemented with vitamin A seemed to have an improved immune status.
育肥猪（N=224；体重 28.66±1.90 千克）被随机分配到 56 个栏中，每个栏中有 4 头公猪或母猪，并分配到四种日粮中的一种：对照组（7656IU 维生素 A/千克）、对照组添加维生素 A（4.36ppm，DSM 公司的 Rovimix A1000，新泽西州帕西帕尼）、对照组添加β-胡萝卜素（163.28ppm，DSM 公司的 Rovimix β-胡萝卜素 10%，帕西帕尼）或对照组添加氧化β-胡萝卜素（40ppm；10%活性成分，奥塔瓦的 Avivagen）。在研究开始时（d0）和每个阶段结束时（d21、42 和 63）测量猪和饲料的重量。一部分母猪在 d0 时通过颈静脉采血，在 d18 时采血并接种细胞内劳森氏菌和猪圆环病毒 2（PCV2），在 d39 时采血并加强接种 PCV2，在 d60 时采血，在 d63 时进行最后一次采血。研究结束时，母猪被安乐死以获得肝脏（整个右叶）和空肠样本（长度的 10%为 15.24 厘米）。此外，还收集了第二和第四前乳头，以评估前乳头组织。数据使用 SAS 9.4（统计分析系统，卡里，北卡罗来纳州）中的 GLIMMIX 程序进行分析。与维生素 A 补充相比，氧化β-胡萝卜素补充增加了（P=0.02）各阶段的 ADG，尽管猪的体重没有差异（P=0.18）。日粮对血浆或肝脏视黄醇、IgG 或 IgM 水平或发育中乳腺组织中免疫细胞的存在没有影响（P>0.05）。补充维生素 A 倾向于（P=0.05）增加空肠中视黄醇结合蛋白的 mRNA 丰度，但其他基因（醇脱氢酶 1 类、卵磷脂视黄醇酰基转移酶、β-胡萝卜素加氧酶 1）的 mRNA 丰度不受日粮处理的影响（P>0.05）。circovirus S/P 比值注意到日粮与时间的相互作用（P=0.04），其中维生素 A 补充与其他日粮相比具有最佳比值。分析的 circovirus 疫苗效价存在日粮与时间的相互作用（P<0.01），其中维生素 A 补充在研究结束时具有最高效价。因此，与维生素 A 补充的猪相比，补充氧化β-胡萝卜素的猪 ADG 提高，但补充维生素 A 的猪似乎具有更好的免疫状态。
