Hematological and biochemical profiles of Mangalarga Marchador mares in the transition period bred on pasture

ABSTRACT The present study aimed to evaluate the effects of the transition period on hematological and biochemical constituents in Mangalarga Marchador mares. Forty-eight mares were used to form a maintenance group (MG) and transition group (TG), formed by pregnant mares and, after delivery, infants. Blood samples were collected at the following times: T-60 (60 d pre-delivery), T-30 (30 d pre-delivery), T-15 (15 d pre-delivery), T0 (first 6h post-delivery), T15 (15 d post-delivery), T30 (30 d post-delivery), and T60 (60 d post-delivery). The TG had lower values (P< 0.05) of red blood cells, hematocrit and hemoglobin at T0, T15, T30 and T60 times than MG. The mean corpuscular volume was lower in MG (P< 0.05) than in TG (T0, T15, T30 and T60) and mean corpuscular hemoglobin concentration was higher (P< 0.05) in MG than in TG (T15, T30 and T60). On the other hand, the diameter distribution of red blood cells presented a lower value (P< 0.05) in MG than in TG (T15 and T30). Mares in transition period presented regenerative anemia. The results demonstrate physiological metabolic variations of different intensities during pregnancy, delivery and early lactation.

摘要 本研究旨在评估过渡期对曼加尔加马查多母马（Mangalarga Marchador）血液学与生化指标的影响。选取48匹母马，分为维持组（maintenance group, MG）与过渡期组（transition group, TG）；其中过渡期组包含妊娠母马及其分娩后的幼驹。分别于以下时间点采集血液样本：分娩前60天（T-60）、分娩前30天（T-30）、分娩前15天（T-15）、分娩后最初6小时（T0）、分娩后15天（T15）、分娩后30天（T30）及分娩后60天（T60）。相较于维持组，过渡期组在T0、T15、T30及T60时间点的红细胞计数、红细胞压积与血红蛋白含量均显著降低（P<0.05）。平均红细胞体积在维持组中显著低于过渡期组（T0、T15、T30及T60，P<0.05）；而平均红细胞血红蛋白浓度在维持组中显著高于过渡期组（T15、T30及T60，P<0.05）。另一方面，红细胞分布宽度在维持组中显著低于过渡期组（T15与T30，P<0.05）。处于过渡期的母马表现出再生性贫血特征。本研究结果揭示了妊娠、分娩及早期泌乳阶段不同强度的生理代谢变化。