The transition period, from pregnancy to lactation, implies comprehensive metabolic and endocrine changes including a systemic inflammatory reaction and oxidative stress around calving in dairy cows. The aim of the present study was a longitudinal characterization of the serum concentration of acute phase proteins (APP), i.e., haptoglobin (Hp), serum amyloid A (SAA) and acidic glycoprotein (AGP), as well as of markers for oxidative stress in another large dairy animal, i.e. water buffalo, during the transition from late pregnancy to early lactation. As indicators of oxidative status, derivatives of reactive oxygen metabolites (dROM), ferric reducing ability (FRAP), thiobarbituric acid reactive substances (TBARS), and advanced oxidation protein products (AOPP) were determined in serum. Indicators for metabolic stress included nonesterified fatty acids (NEFA), ß-hydroxybutyrate (BHB) and adiponectin. Bovine specific ELISA methods for Hp and adiponectin were adapted and validated for their application to water buffalo samples. Blood samples were collected weekly from 11 pluriparous water buffalo cows (lactation number 4.6 ± 1.6; daily milk yield 9.0 ± 1.9 kg; means ± SD) from 6 weeks (wk) ante partum (ap) until 8 wk post partum (pp). The maximum concentrations of Hp were observed in wk 1 pp, followed by a decrease towards values lower than before calving starting from wk 3 pp. The concentrations of SAA also peaked in wk 1 pp and then returned to basal values. The AGP serum concentrations increased suddenly from the first to the second wk pp and remained elevated for all the observation period.

Indicators of oxidative status which changed in concentration during the transition period were dROM, AOPP and the oxidative stress index (OSi) (dROM/FRAP ratio). Briefly, dROM and AOPP values were lower pp as compared to ap, and OSi was largely following the pattern of dROM due to the constant FRAP values. The TBARS values did not change during the observation period.

From the metabolic indicators, adiponectin was not changing with time, whereas greater NEFA and BHB values were observed ap than pp. The time course of NEFA and of some indicators for oxidative status (dROM, OSi and AOPP) point to greater metabolic load in late pregnancy as compared with the first wk of lactation - contrary to the common situation in dairy cows. Both BHB and NEFA values remained below the thresholds applied for dairy cows to define subclinical or clinical ketosis, thus indicating that the buffaloes included in this study were not under metabolic stress. The increase in concentration of the APP around calving supports the concept that an inflammatory reaction is a physiological epiphenomenon of the onset of lactation in water buffalos that is independent of metabolic stress.

从怀孕到哺乳期的过渡期意味着全面的代谢和内分泌变化，包括乳牛产犊前后的全身性炎症反应和氧化应激。本研究的目的是纵向表征急性期蛋白（APP），即触珠蛋白（Hp），血清淀粉样蛋白A（SAA）和酸性糖蛋白（AGP）的浓度，以及氧化应激的标志物从怀孕后期到早期哺乳的过渡时期，另一种大型奶牛动物，即水牛。作为氧化状态的指标，在​​血清中测定了活性氧代谢产物（dROM），铁还原能力（FRAP），硫代巴比妥酸反应性物质（TBARS）和高级氧化蛋白产物（AOPP）。代谢应激的指标包括非酯化脂肪酸（NEFA），β-羟基丁酸酯（BHB）和脂联素。对Hp和脂联素的牛特异性ELISA方法进行了修改，并验证了它们在水牛样品中的应用。每周从产前6周（wk）到产后8 wk（pp），每周从11头多头水牛（泌乳数4.6±1.6；每日产奶量9.0±1.9 kg；平均值±SD）采集血液样本。Hp的最大浓度以wk 1 pp为单位观察，然后下降至比产犊前更低的值，从wk 3 pp开始。SAA的浓度也以wk 1 pp达到峰值，然后恢复到基础值。从第一周到第二周，AGP血清浓度突然升高，并且在整个观察期内均保持升高。ß-羟基丁酸酯（BHB）和脂联素。对Hp和脂联素的牛特异性ELISA方法进行了修改，并验证了它们在水牛样品中的应用。每周从产前6周（wk）到产后8 wk（pp），每周从11头多头水牛（泌乳数4.6±1.6；每日产奶量9.0±1.9 kg；平均值±SD）采集血液样本。Hp的最大浓度以wk 1 pp为单位观察，然后下降至比产犊前更低的值，从wk 3 pp开始。SAA的浓度也以wk 1 pp达到峰值，然后恢复到基础值。从第一周到第二周，AGP血清浓度突然升高，并且在整个观察期内均保持升高。ß-羟基丁酸酯（BHB）和脂联素。对Hp和脂联素的牛特异性ELISA方法进行了修改，并验证了它们在水牛样品中的应用。每周从产前6周（wk）到产后8 wk（pp），每周从11头多头水牛（泌乳数4.6±1.6；每日产奶量9.0±1.9 kg；平均值±SD）采集血液样本。Hp的最大浓度以wk 1 pp为单位观察，然后下降至比产犊前更低的值，从wk 3 pp开始。SAA的浓度也以wk 1 pp达到峰值，然后恢复到基础值。从第一周到第二周，AGP血清浓度突然升高，并且在整个观察期内均保持升高。对Hp和脂联素的牛特异性ELISA方法进行了修改，并验证了它们在水牛样品中的应用。每周从产前6周（wk）到产后8 wk（pp），每周从11头多头水牛（泌乳数4.6±1.6；每日产奶量9.0±1.9 kg；平均值±SD）采集血液样本。Hp的最大浓度以wk 1 pp为单位观察，然后下降至比产犊前更低的值，从wk 3 pp开始。SAA的浓度也以wk 1 pp达到峰值，然后恢复到基础值。从第一周到第二周，AGP血清浓度突然升高，并且在整个观察期内均保持升高。对Hp和脂联素的牛特异性ELISA方法进行了修改，并验证了它们在水牛样品中的应用。每周从产前6周（wk）到产后8 wk（pp），每周从11头多头水牛（泌乳数4.6±1.6；每日产奶量9.0±1.9 kg；平均值±SD）采集血液样本。Hp的最大浓度以wk 1 pp为单位观察，然后下降至比产犊前更低的值，从wk 3 pp开始。SAA的浓度也以wk 1 pp达到峰值，然后恢复到基础值。从第一周到第二周，AGP血清浓度突然升高，并且在整个观察期内均保持升高。0±1.9公斤; 是指产前6周（wk）产前（ap）到产后8 wk（pp）的±SD）。Hp的最大浓度以wk 1 pp为单位观察，然后下降至比产犊前更低的值，从wk 3 pp开始。SAA的浓度也以wk 1 pp达到峰值，然后恢复到基础值。从第一周到第二周，AGP血清浓度突然升高，并且在整个观察期内均保持升高。0±1.9公斤; 是指产前6周（wk）产前（ap）到产后8 wk（pp）的±SD）。Hp的最大浓度以wk 1 pp为单位观察，然后下降至比产犊前更低的值，从wk 3 pp开始。SAA的浓度也以wk 1 pp达到峰值，然后恢复到基础值。从第一周到第二周，AGP血清浓度突然升高，并且在整个观察期内均保持升高。

在过渡期间浓度发生变化的氧化状态指标为dROM，AOPP和氧化应激指数（OSi）（dROM / FRAP比）。简而言之，与ap相比，dROM和AOPP值pp更低，并且由于FRAP值恒定，因此OSi在很大程度上遵循dROM的模式。在观察期间，TBARS值没有变化。

从代谢指标来看，脂联素没有随时间变化，而观察到的ap高于pp。NEFA和某些氧化状态指标（dROM，OSi和AOPP）的时程表明后期后期的代谢负荷更大。与泌乳初期的第一周相比怀孕-与奶牛的常见情况相反。BHB和NEFA值均保持在奶牛定义亚临床或临床酮症所适用的阈值以下，因此表明该研究中包含的水牛没有处于代谢应激状态。产犊前后APP浓度的增加支持了以下观点：炎症反应是水牛泌乳开始的生理现象，与代谢应激无关。