Effects of age and season on haematological parameters of donkeys during the rainy and cold–dry seasons

Abstract

The aim of the study was to investigate the effects of age and season on haematological parameters of donkeys at rest during the rainy and cold-dry seasons. Thirty healthy donkeys divided into three groups based on their age served as the subjects. During each season, blood sample was collected from each donkey thrice, 2 weeks apart, for haematological analysis, and the dry-bulb temperature (DBT), relative humidity (RH) and temperature-humidity index (THI) were obtained thrice each day during the experimental period using standard procedures. During the rainy season, the mean DBT (33.05 ± 0.49 °C), RH (73.63 ± 1.09 %) and THI (84.39 ± 0.71) were higher (P < 0.0001) than the corresponding values of 24.00 ± 0.44 °C, 36.80 ± 0.92 % and 64.80 ± 0.62, during the cold-dry season. Packed cell volume (PCV), erythrocyte count [red blood cell (RBC)], haemoglobin concentration (Hb), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), platelet count (PLT), leucocyte count [white blood cell (WBC)], lymphocyte count (LYM) and neutrophil/lymphocyte ratio (N/L) were higher (P < 0.05) in adults than foals during the rainy season. The MCV, MCH, WBC, NEU, LYM and PLT of adult and yearling donkeys were higher (P < 0.05) during the rainy than the cold-dry season. The PCV, RBC, Hb, MCV, MCH, and NEU of foals were higher in the rainy than the cold-dry season. The N/L of adult and foal donkeys were higher (P < 0.05) in the rainy than in the cold-dry season. In conclusion, PCV, RBC, Hb and LYM were considerably higher in foals than yearlings or adults during the rainy season, while erythrocytic indices and platelet counts were higher in adults or yearlings than in foals in both seasons. Erythrocytic indices, PLT and N/L were higher in the rainy than the cold-dry season in adults, yearlings and foals.

Influence of seasonal changes on physiological variables, haematology and serum thyroid hormones profile in male Red Sokoto and Sahel goats

“…This suggests that decrease in MCV may have the potential of being used as an animal-based indicator of heat stress in tropical goats naturally exposed to heat stress. On the other hand, the increase in MCV during the RAS agrees with a study in donkeys, conducted in the same region (Zakari et al 2015). This may be due to seasonal changes in the quantity and nutritional quality of availability pasture.…”

Effect of season, age, and sex on haematology and serum biochemistry of sport horses

“…However, Hb, RBC and TWBC levels were high during the dry season than in the rainy season. This is in agreement with earlier reports on donkey (Zakari et al, 2015) and red sokoto goats (Habibu et al, 2016). These increases may be attributed to dehydration during the dry season resulting to haemoconcentration.…”

“…There were no seasonal variations in the PCV, MCV, MCHC and MCH values in this study. This is in agreement with previous studies by Ihedioha et al (2013) for horses in Enugu, Zakari et al (2015) for donkeys, Habibu et al, (2016) and Olayemi et al (2015) for Red Sokoto goats. However, Hb, RBC and TWBC levels were high during the dry season than in the rainy season.…”

Effects of winter and spring housing on growth performance and blood metabolites of Pengbo semi-wool sheep in Tibet

“…The normal values of physiological and biochemical indexes are used for evaluating stress and the well-being of an animal. In the present study, winter grazing of ewes resulted in a decreased WBC count, in line with the report by Zakari et al [14], who found that the WBCs of donkeys decreased during the cold dry season. The physiological responses of animals to environmental stress and their energy balance have profound effects on serum biochemical parameters.…”