中文摘要：

为了解肉牛发生亚急性瘤胃酸中毒时血液学和相应生化指标的变化，对瘤胃液pH在5．2～5．5、5．6～5．8和5．9～6．8之间的24头肉牛进行了血液学及相应生化指标的分析。结果表明：随着pH值的降低，血液中红细胞（RBC）数量、血红蛋白（Hb）浓度、红细胞压积（PCV）均显著增加；白细胞（WBC）总数上升，白细胞分类（WBC—DC）也有相应的变化，嗜酸性粒细胞和淋巴细胞呈下降趋势，中性杆状核粒细胞和中性分叶核粒细胞呈上升趋势，单核细胞略微升高；血气指标pO2显著增加，pCOz、HCO3-浓度显著减少；生化指标Ca2＋、Cl-显著减沙，Na＋和尿素氮显著增加，K＋差异不显著。肉牛发生轻度和中度亚急性瘤胃酸中毒时，pCO2以及HC07含量显著降低，表明机体碱储备不足，缓冲能力下降，存在代偿性酸中毒；同时根据水合状态和血象指标，表明亚急性瘤胃酸中毒病牛存在轻度脱水和炎性反应。

英文摘要：

The aim of this study was to investigate the changes of hematology and biochemical pa- rameters in beef cattle with subacute ruminal acidosis. We analyzed the hematology and biochemical parameters of 24 beef cattle with ruminal pH value in 5.2-5.5,5.6-5.8 and 5.9-6.8. The results showed that red blood cell （RBC）, haemoglobin （Hb）, packed cell volume（PCV）significantly increased with the reducing pH value, the number of white blood cell（WBC）was increased. The leukocyte differential count was changed in the different degree, the proportion of eosinophilic leukocyte and lymphocyte was decreased,neutrophilic stab and segmented granulocyte was increased, mononuclear leucocyte was increased slightly. The pO2 was significantly increased. The pCO2 and HCO; were significantly decreased. The levels of Ca2＋ and Cl- were significantly decreased, the levels of Na＋ and urea nitrogen were significantly increased,and there was no Significant difference in the levels of K＋. The decreased pCO2 and HCO3- in the slight and moderate sick cattle indicate that the alkaline reserve was insufficient and the buffering capacity was reduced in the organism, thereby resulting in compensated acidosis. Mild dehydration and inflammatory reaction occurred in cattle with SARA.