Hematological profile in holstein dairy cows according to the different physiological stage

Abstract

This study aims to investigate the variations of hematological and ionic parameters of Holstein dairy cows according to the physiological stage, as an indicator of their health status. The survey was conducted between January and March, 2020 and carried out on 4 lots of 15 dairy cows each. The analysis of blood parameters included: red blood cells (RBC), hematocrit (HCT), hemoglobin (HGB), mean corpuscular volume (MCV), mean corpuscular hemoglobin content (MCH), mean corpuscular hemoglobin concentration (MCHC), platelets (PLT), white blood cells (WBC), lymphocytes (LYM), monocytes (MONO), neutrophils (NEU), eosinophils (EOS), basophils (BASO) and ionic parameters such as potassium (K), chlorine (Cl), calcium (Ca), phosphorus (P) and sodium (Na). The RBC level was lowest in the 2nd third of gestation (6.0 ± 0.8 x 106/μL) and in postpartum period (5.6 ± 0.8 x 106/μL), in comparison to the 1st third (6.6 ± 0.6 x 106 / μL) and 3rd third (dry period) of gestation (6.7 ± 0.5 x 106 / μL) (p<0.0001). The same observation was noted for HCT (p<0.0001). MCV was highest in dry cows (p<0.01). MCH and MCHC were highest in cows that were in the postpartum period (p<0.001). For WBC, the count was higher in the 1stthird of gestation compared to the other stages, (11.3 ± 2.2 x 103 / μL) versus (6.4 ± 4.1 x 103 / μL), (5.2 ± 1.3 x 103 / μL), and (8.0 ± 4.9 x 103 / μL) for the 2nd third, 3rd third of gestation, and postpartum, respectively (p<0.001).
In postpartum cows, the ionic parameters had the lowest values of potassium (K), calcium (Ca) and phosphorus (P) compared to
the other stages (p<0.001). This investigation can be used as a basis for information on the hematological and ionic profile of dairy cattle in order to determine the health status before the onset of clinical signs.