The aim of the study was to evaluate blood cellular responses and erythrocyte osmotic fragility (EOF), as an index of oxidative stress, in pregnant Yankasa ewes and their lambs. Blood samples were collected from each ewe at pre-gestation, gestation (weeks 3, 10 and 17, corresponding to early-, mid-, and late-gestation, respectively), prepartum (weeks 18 and 19), postpartum (immediately after lambing, weeks 1 and 3); and from their lambs postpartum. The blood samples were used to determine blood cellular parameters and EOF. Results revealed higher (P < 0.05) packed cell volume (PCV) and red blood cell (RBC) counts at mid-gestation than prepartum and postpartum values. Neutrophil-lymphocyte ratio was higher (P < 0.05) on parturition day compared to other stages. There was no significant (P> 0.05) difference in EOF during the different stages in the dams. On the day of lambing, PCV, haemoglobin and lymphocyte counts were higher (P < 0.05) in lambs than dams, but lower neutrophil count was recorded in the lambs compared to dams. The EOF was lower in lambs than their dams (P < 0.05) on the day of lambing. In conclusion, the mid-gestation PCV and RBC values were higher than pre- and post-partum values, whereas parturition influenced neutrophil-lymphocyte ratio compared to other stages. The results showed that most blood cellular changes occurred during the periparturient period, when most life-threatening disorders affect ewes. Erythrocyte membranes of lambs were more resistant to hypotonicity, indicating that the erythrocyte membranes of the lambs were less vulnerable to oxidative stress damage than those of their dams. Hence, Yankasa lambs may be more resistant to immediate postpartum oxidative stress than their dams.

该研究的目的是评估Yankasa母羊及其羔羊的血细胞反应和红细胞渗透性脆弱性（EOF），作为氧化应激的指标。在妊娠前，妊娠（分别为第3、10和17周，分别对应于妊娠早期，中期和晚期），产前（第18和19周），产后（产羔后立即）从每只母羊采集血样，第1周和第3周）；和产后的羔羊。血样用于确定血细胞参数和EOF。结果显示，妊娠中期的堆积细胞体积（PCV）和红细胞（RBC）计数高于（P <0.05）产前和产后的数值。中性粒细胞-淋巴细胞比率较高（P<0.05）与其他阶段相比。大坝不同阶段的EOF没有显着差异（P > 0.05）。产羔当天，羔羊的PCV，血红蛋白和淋巴细胞计数高于大坝（P <0.05），但羔羊的中性粒细胞计数却比大坝低。羔羊的EOF低于其母坝（P<0.05）。总之，妊娠中期的PCV和RBC值高于产前和产后的值，而分娩与其他阶段相比会影响中性粒细胞-淋巴细胞的比率。结果表明，大多数血细胞变化发生在围产期，而大多数威胁生命的疾病影响母羊。羔羊的红细胞膜对低渗性的抵抗力更强，表明羔羊的红细胞膜比其大坝的红细胞膜更不易受到氧化应激的损害。因此，扬卡萨（Yankasa）羔羊可能比母羊更能抵抗立即的产后氧化应激。