Background: The dried blood spot (DBS) technique using filter papers has revolutionized the conventional blood sampling techniques through ease of blood collection, storage and transport. Various analytes (such as hormones, antigens, antibodies and hematochemical attributes) are being estimated through DBS globally. However, this technique has not yet been implied in Pakistan. This research work is the first of its kind regarding hemoglobin (Hb) estimation in Cholistani cattle (n=63) blood through DBS technique using filter paper.Methods: Three methods of Hb estimation were implied in the present study viz. through veterinary hematology analyzer (HbA), and two indirect cyanmethemoglobin methods (HbIC and HbICX) using measured (20µL) and unmeasured blood drops on the filter paper, respectively.Results: Results revealed that HbA and HbIC were non-significantly (P≥0.05) different from each other, being different from HbICX (P≤0.05). The HbICX gave overestimated values of Hb as compared to HbA and HbIC. The sensitivity, specificity, positive predictive value, and negative predictive value for HbIC were higher being 86.1%, 88.3%, 88.0%, and 86.0%, respectively as compared to the lower values of 45.0%, 12.0%, 12.0% and 45.0%, for HbICX. Bland and Altman test revealed a better level of agreement between HbA and HbIC. Around the mean difference line, there was no proportional bias in data distribution (Mean= -0.16, 95% CI= 0.34 to -0.67). Similarly, measures attained through Cronbach alpha and intraclass correlation coefficient between HbA and HbIC were higher being 0.703 and 0.825 values for single and average, respectively, as compared to the values of 0.200 and 0.333 between HbA and HbICX.Conclusion: It is concluded that the indirect cyanmethemoglobin method for Hb estimation is reliable and accurate for cattle blood, if a measured quantity of blood drop is taken on a filter paper. We recommend this DBS technique for Hb estimation in cattle blood for resource-poor settings and for livestock herds being reared distantly from the laboratories. For future, it is recommended that DBS technique with various other modifications and for other hematochemical biomarkers may be validated for livestock blood.Keywords: Dried blood spot; Hemoglobin; Cholistani cattle
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