我们的目标是评估补充痕量矿物质(TM)形式无机盐(STM;Co,Cu,Mn,硫酸锌,和亚硒酸钠)或有机(OTM;Co,Cu,Mn,蛋白质锌,和硒化酵母)-在产前饮食中对初乳的数量和质量,被动免疫,抗氧化剂生物标志物,细胞因子对脂多糖(LPS)的反应,健康,和新生小牛的生长。在产牛前45天,招募了怀孕的小母牛(n=100)和母牛(n=173),被胎次和身体状况分数所阻挡,并随机分配给STM(50头母牛;86头母牛)或OTM(50头母牛;87头母牛)补充。两种治疗方法的奶牛都饲喂相同的饮食,除了补充TM的来源。产牛2小时内,水坝和小牛被分开了,收获了初乳,测量了产量,并保存样本用于初乳质量的后验分析。一组小牛(n=68)在饲喂初乳之前收集了血液样本。初乳喂养后,所有样本和数据收集仅限于163头小牛(STM=82;OTM=81),在收获后几分钟通过奶瓶饲喂3L优质(白利糖度%>22)的母体初乳。初乳饲喂24小时后,使用放射免疫扩散测定初乳和血清中IgG的浓度。通过电感耦合等离子体质谱法测定初乳和血清中TM的浓度。谷胱甘肽过氧化物酶的活性,等离子体的铁还原能力,通过比色法评估血浆中超氧化物歧化酶的浓度。在生命的第7天进行用LPS的离体全血刺激,以评估66只小牛的亚组中的细胞因子应答。记录从出生到断奶的健康事件,出生时(所有小牛)和第30天和第60天(仅限小母牛)记录体重。用方差分析分析连续变量,用逻辑回归分析二元反应。产前饮食中OTM完全替代STM导致硒浓度更高(461vs.543±7μg/g;±SEM),但没有改变初乳中其他TM和IgG的浓度或总质量。OTM组的雌性小牛在出生时血清中的硒浓度更高(0.23vs.0.37±0.05μg/mL),出生时体重较轻(40.9vs.38.8±0.6公斤)和断奶(93.2与比STM组的89.7±1.6kg)。母亲治疗不影响被动免疫或抗氧化生物标志物。在第7天,IFNγ的基础浓度(以pg/mL为单位的浓度的log10)(0.70vs.0.95±0.083)和LPS刺激的CC趋化因子配体2浓度(CCL2;2.45vs.2.54±0.026),CC趋化因子配体3(CCL3;2.63vs.2.76±0.038),IL-1α(2.32vs.2.49±0.054),和IL-1β(3.62vs.OTM中的3.86±0.067)高于STM。在怀孕的母牛中补充OTM,但不是在怀孕的母牛身上,降低了小牛断奶前健康问题的发生率(36.4vs.11.5%)。在产前饮食中用OTM完全替代STM并没有引起初乳质量的重大变化,被动免疫,和抗氧化能力,但是在生命的第7天增加了对LPS的细胞因子和趋化因子反应,并有益于初产母牛出生的小牛的断奶前健康。
Our objectives were to evaluate the impact of supplementary trace mineral (TM) form-inorganic salts (STM; Co, Cu, Mn, Zn sulfates, and Na selenite) or organic (OTM; Co, Cu, Mn, Zn proteinates, and selenized yeast)-in the prepartum diet on quantity and quality of colostrum, passive immunity, antioxidant biomarkers, cytokine responses to lipopolysaccharide (LPS), health, and growth of newborn calves. Pregnant heifers (n = 100) and cows (n = 173) were enrolled at 45 d before calving, blocked by parity and body condition score, and allocated randomly to STM (50 heifers; 86 cows) or OTM (50 heifers; 87 cows) supplementation. Cows in both treatments were fed the same diet, except for the source of supplementary TM. Within 2 h of calving, dams and calves were separated, colostrum was harvested, the yield was measured, and a sample was saved for posterior analyses of colostrum quality. A subgroup of calves (n = 68) had a blood sample collected before colostrum feeding. After colostrum feeding, all samples and data collection were limited to 163 calves (STM = 82; OTM = 81) fed 3 L of good quality (Brix% >22) maternal colostrum via nipple bottle minutes after harvesting. Concentration of IgG in colostrum and serum was determined 24 h after colostrum feeding using radial immunodiffusion. Concentration of TM in colostrum and serum were performed by inductively coupled plasma mass spectrometry. Activity of glutathione peroxidase, ferric reducing ability of plasma, and concentration of superoxide dismutase were evaluated in plasma by colorimetric assays. Ex vivo whole blood stimulation with LPS was performed on d 7 of life to evaluate cytokine responses in a subgroup of 66 calves. Health events were recorded from birth to weaning, and body weight was recorded at birth (all calves) and on d 30 and 60 (heifers only). Continuous variables were analyzed by ANOVA and binary responses were analyzed by logistic regression. Complete replacement of STM by OTM in prepartum diet resulted in greater concentration of Se (461 vs. 543 ± 7 μg/g; ± SEM) but did not alter the concentration or total mass of other TM and IgG in colostrum. Female calves of the OTM group had greater concentration of Se in serum at birth (0.23 vs. 0.37 ± 0.05 μg/mL), were lighter in weight at birth (40.9 vs. 38.8 ± 0.6 kg) and weaning (93.2 vs. 89.7 ± 1.6 kg) than those of the STM group. Maternal treatments did not affect passive immunity or antioxidant biomarkers. On d 7, basal concentrations (log10 of concentration in pg/mL) of IFNγ (0.70 vs. 0.95 ± 0.083) and LPS-stimulated concentrations of CC chemokine ligand 2 (CCL2; 2.45 vs. 2.54 ± 0.026), CC chemokine ligand 3 (CCL3; 2.63 vs. 2.76 ± 0.038), IL-1α (2.32 vs. 2.49 ± 0.054), and IL-1β (3.62 vs. 3.86 ± 0.067) were greater in OTM than in STM. Supplementation with OTM in pregnant heifers, but not in pregnant cows, reduced the incidence of preweaning health problems in their calves (36.4 vs. 11.5%). Complete replacement of STM by OTM in the prepartum diet did not cause major changes in colostrum quality, passive immunity, and antioxidant capacity, but increased cytokine and chemokine responses to LPS on d 7 of life and benefited preweaning health of calves born to primiparous cows.