Seasonal variations in hematological profile of Holstein dairy cows as an indicator for physiological status assessment

This study aims to investigate, for the first time in Algeria, the effect of seasonal climatic changes on the hematological profile of Holstein dairy cows as an indicator for their physiological status assessment. The study was conducted between November 2018 and October 2019 and was performed on a lot of 14 dairy cows. Blood samples were collected quarterly during this study period. The data regarding seasonal changes in hematological parameters were not significant concerning red blood cell count (RBC), hemoglobin concentration (Hb) and mean corpuscular volume (MCV). However, variations were significant for hematocrit (HCT), mean corpuscular hemoglobin content (MCH), mean corpuscular hemoglobin concentration (MCHC) and blood platelets (PLT). The percentage of HCT was higher in autumn (27.99%) and spring (28.58%) compared to winter (26.52%) and summer (26.75%), (p