Haematological values of cows during third trimester of pregnancy and early lactation in settled cattle herds in Zaria, Northern Nigeria 1*

The haematological values of 176 cows during third trimester of pregnancy and early lactation in nine settled cattle herds in Zaria, Northern Nigeria, were studied. The total mean values of total protein (TP), packed cell volume (PCV), haemoglobin (Hb), red blood cell (RBC) and white blood cell (WBC) during pregnancy and early lactation did not differ significantly (P≥0.05) while neutrophil, lymphocyte, monocyte and eosinophil values differed significantly (P <0.05). Neutrophil and lymphocyte values during early lactation were higher than those during third trimester of pregnancy, while monocyte and eosinophil values during third trimester of pregnancy were higher than those of early lactation. The herds mean haematological values closely resembled those of the total mean values. The herds mean values of TP, PCV, Hb, RBC and WBC during third trimester of pregnancy and early lactation did not differ significantly (P <0.05) except in one herd (VIII) where the early lactation value was significantly (p <0.05) higher. In some herds, the mean values of neutrophil, lymphocyte and monocyte during third trimester of pregnancy were significantly (p <0.05) higher than those of early lactation while in others, they were significantly (p <0.05) lower. The mean values of eosinophil during lactation were significantly higher than those of third trimester pregnancy in all the herds. This study has provided reference haematological values of cows that may be safely assumed to be adequate and consistent with normal health and metabolic state during third trimester of pregnancy and early lactation. The study has also confirmed the significant effect of herd factor on haematological parameters of cows.