Devising and validating a pen-side hematological formula for hemoglobin estimation in Cholistani cattle

The present study has been designed to devise a pen-side hematological formula for estimation of hemoglobin (Hb) from packed cell volume (PCV) in Cholistani breed of cattle being reared under pastoralism in Cholistan desert, Pakistan. It also aims to validate the soundness of rule of calculating Hb concentration as one-third of PCV and vice versa as being used in human medicine. Cholistani cattle (n = 364) were bled for PCV determination (microhematocrit) method and Hb estimation (hematology analyzer) (HbD) as well as through calculation being one-third of PCV (HbC). The independent-sample t-test was implied for deducing difference between HbD and HbC, and between HbD and corrected Hb (CHb) for all study groups. The CHb was deduced through regression prediction equation attained from linear regression model. Scatter-plots were drawn and linear regression was carried out between various studied hematological attributes. Significantly (P ≤ 0.01) positive correlation coefficient was noticed for all study groups being highest for female adult stock (r = 0.893; adjusted R-square = 0.79) between HbD and PCV and between HbD and HbC. The regression equation for overall results attained, i.e., Hb = 0.13 (PCV) + 6.3 was used to deduce CHb. A non-significant (P ≥ 0.05) difference was noticed between HbD and CHb. In conclusion, a convention of human clinical medicine that Hb concentration is third of PCV and vice versa cannot be implied for Cholistani cattle. A different equation, i.e., Hb (g/dL) = 0.13 (PCV) + 6.3 may provide reliable results for Hb estimation from the PCV in cattle.