我们的目标是评估完全替代微量矿物质的补充无机盐的影响(ITM;Co,Cu,Mn,硫酸锌和亚硒酸钠)由有机痕量矿物(OTM;Co,Cu,Mn,锌蛋白和硒化酵母)在产前和产后饮食中对体液和肝脏中TM浓度的影响,血液中的抗氧化剂和炎症生物标志物,和奶牛的产后健康。怀孕的母牛被胎次和BCS封闭,并在预期产卵前45天随机分配到ITM(n=136)或OTM(n=137)。除补充TM的来源外,两组均接受相同的产前和产后饮食。产卵日被认为是研究d〇,并且在d-45、-21、-14、-10、-7、-3、0、3、7、10、14、23、65和105收集血液用于TM和生物标志物的分析。还研究了肝脏中TM的浓度(第105天),牛奶(D7,23,65,105),尿液(d-21,21,65,105),瘤胃液和粪便(d-21,21,65)。评估了临床和亚临床健康状况的发生率。OTM完全替代ITM导致血清中硒浓度更高(0.084vs.0.086µg/mL;P<0.01),牛奶(0.24vs.0.31µg/g;P<0.01),和瘤胃液(0.54vs.0.58微克/克;P=0.06),并降低尿液中硒的浓度(1.54vs.1.23µg/g;P<0.01)。对于血清中Co的浓度,治疗与时间间存在交互作用(P<0.01)。补充OTM的奶牛在d-7和0时的Co浓度更高(0.30vs.0.33ng/mL;P<0.01),但在第23、65和105天的Co浓度较低(0.34vs.0.31ng/mL;P<0.05),除了降低粪便中Co的浓度(1.08vs.0.99微克/克;P=0.04)和,仅适用于多胎,在尿液中(0.019vs.0.014微克/克;P<0.01)。补充OTM的奶牛产后谷氨酸脱氢酶浓度较低(20.8vs.17.8U/L;P<0.05),d-10时白蛋白较高(36.0vs.36.7g/L;P=0.04)和23(36.9与37.6g/L;P=0.03)相对于产卵。饲喂OTM的初产母牛血浆中铜蓝蛋白的浓度较低(55vs.51mg/L;P≤0.05)。补充OTM的奶牛跛行发生率较低(14vs.7%;P=0.05),升高的NEFA(61vs.44%;P<0.01),和多种代谢问题(35vs.20%;P<0.01)。尽管铜缺乏差异,Mn,锌浓度和抗氧化能力,用OTM完全替代ITM,改变了Se和Co的浓度,支持肝脏和蹄的健康,并降低产后NEFA升高的风险。
Our objectives were to evaluate the effects of complete replacement of supplementary inorganic salts of trace minerals (ITM; cobalt (Co), copper (Cu), manganese (Mn), zinc (Zn) sulfates and sodium (Na) selenite) by organic trace minerals (OTM; Co, Cu, Mn, Zn proteinates, and selenized yeast) in both pre- and postpartum diets on trace minerals (TM) concentrations in body fluids and liver, antioxidant and inflammation biomarkers in blood, and postpartum health of dairy cows. Pregnant cows were blocked by parity and body condition score and randomly assigned to ITM (n = 136) or OTM (n = 137) 45 d before expected calving. Both groups received the same pre- and postpartum diets except for the source of supplementary TM. The day of calving was considered study d 0 and blood was collected on d -45, -21, -14, -10, -7, -3, 0, 3, 7, 10, 14, 23, 65, and 105 for analyses of TM and biomarkers. Concentrations of TM were also investigated in the liver (d 105), milk (d 7, 23, 65, 105), urine (d -21, 21, 65, 105), ruminal fluid and feces (d -21, 21, 65). Incidence of clinical and subclinical health conditions were evaluated. Complete replacement of ITM by OTM resulted in greater concentration of selenium (Se) in serum (0.084 vs. 0.086 µg/mL; P < 0.01), milk (0.24 vs. 0.31 µg/g; P < 0.01), and ruminal fluid (0.54 vs. 0.58 µg/g; P = 0.06), and reduced concentration of Se in urine (1.54 vs. 1.23 µg/g; P<0.01). For concentration of Co in serum, an interaction between treatment and time was detected (P < 0.01). Cows supplemented with OTM had greater concentrations of Co on d -7 and 0 (0.30 vs. 0.33 ng/mL; P < 0.01) but lower concentrations of Co on d 23, 65, and 105 (0.34 vs. 0.31 ng/mL; P < 0.05), in addition to reduced concentration of Co in feces (1.08 vs. 0.99 µg/g; P = 0.04) and, for multiparous only, in urine (0.019 vs. 0.014 µg/g; P < 0.01). Cows supplemented with OTM had lower postpartum concentrations of glutamate dehydrogenase (20.8 vs. 17.8 U/L; P < 0.05) and higher albumin on d -10 (36.0 vs. 36.7 g/L; P = 0.04) and 23 (36.9 vs. 37.6 g/L; P = 0.03) relative to calving. Primiparous cows fed OTM had lower concentration of ceruloplasmin in plasma (55 vs. 51 mg/L; P ≤ 0.05). Cows supplemented with OTM had less incidence of lameness (14% vs. 7%; P = 0.05), elevated nonesterified fatty acids (NEFA) (61% vs. 44%; P < 0.01), and multiple metabolic problems (35% vs. 20%; P < 0.01). Despite the lack of differences in Cu, Mn, and Zn concentrations and antioxidant capacity, complete replacement of ITM by OTM altered concentrations of Se and Co, supported liver and hoof health, and reduced the risk of postpartum elevated NEFA.
Trace minerals (TM) are important for oxidative balance and immunity of cows. Different forms of TM are available for dietary supplementation of dairy cows. We tested whether replacing inorganic salts of TM by organic sources of TM in both pre- and postpartum diets improve TM concentration in body fluids and liver, antioxidant capacity in blood, and postpartum health of dairy cows. Despite the lack of difference in antioxidant capacity and in concentrations of Cu, Mn, and Zn, the complete replacement of inorganic salts by organic sources altered concentrations of Se and Co in circulation, and reduced the concentration of biomarkers associated with inflammation and liver damage, and the risk of lameness and postpartum metabolic problems.