Effect of altitude on some hematological parameters in two Bulgarian local sheep breeds depending also on their body condition score

Ivan Yanchev, Nikola Metodiev, Penka Moneva, Maya Ignatova

Abstract: The aim of the present study was to estimate the values of some blood parameters – red blood cells (RBC) count, hematocrit (HCT), hemoglobin (HGB), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular hemoglobin (MCH) and mean erythrocyte volume (MCV) of two herds of Bulgarian local sheep breeds (closely related genetically), reared at different altitudes in one region, depending on their body condition score (BSC), too. The research was carried out in a farm in Mirkovo village (715 m above sea level) with Sofia (Elin Pelin) local sheep breed and in a farm in Gubesh village (1040 m above sea level) with Central Stara Planina (Balkan) sheep breed. From these two herds of local sheep (1.5-7.5 years old) were selected age-matched groups consisted by 50 animals each, from which blood samples were taken. The body condition score was performed during sampling by one individual using an adapted system. For the purposes of the research, like in our previous researches and because of narrow individual variation, formed subgroups of 10 animals each with the highest and lowest HCT in the analysis of the samples, were also compared. The BCS of sheep from the herd of Central Balkan sheep breed (Gubesh village) was better than that those from Elin Pelin breed (Mirkovo village), as the difference was significant between the herds in the three groups – overall for the herds (P <
0.001) and in the groups with high (P < 0.001) and low (P < 0.01) HCT. The higher altitude in the village of Gubesh together with the better BCS in this herd significantly influenced the levels of HCT in the three groups again (P < 0.001, P < 0.001, and P < 0.01) and MCV – P < 0.05, P < 0.001, and P < 0.05, respectively. The levels of HGB were significantly higher overall for the herds (P < 0.05) and in the group with high HCT (P < 0.05), but the differences in RBC and MCH between all groups were not significant. About the MCHC – there was a high significant difference (P < 0.001) between the breeds in all three groups – overall for the herds and in the groups with high and low HCT which indicates about a specific adaptive response of the sheep’s organism from Elin Pelin sheep breed to maintain a higher concentration of HGB with a smaller volume of erythrocytes for almost the same number of cells.

Keywords: altitude; BCS, hematocrit; hematological parameters; Local sheep

Date published: 2023-08-21