Seasonal variations of some blood parameters in cow

Thermal environment is a major factor that can negatively affect cow performance, especially in animals of high genetic value. Environmental conditions and in particular seasonal variations in air temperature and relative humidity are considered physiological stressors which affect the animal’s biological system. The effect of seasonal variation (winter, spring, summer and autumn) on some haematochemical parameters was evaluated on 43 multiparous Piemontese cows (5-12 years, mean body weight 530±78 kg), obtained from a farm located in Sicily, Italy (latitude 36° 53’ 27”N, longitude 15° 4’ 37”E, 152 m above sea level). For each season, ambient temperature and relative humidity were recorded by means of a data logger. The temperaturehumidity index (THI) was also calculated as indicator of thermal comfort for animals. Blood samples were collected from each subject in January (T1 - winter season), April (T2 - spring season), July (T3 - summer season) and October (T4 - autumn season). Sera obtained were assessed by means of an automated analyzer UV Spectrophotometer (SEAC, Slim, Florence, Italy) on the following hematochemical parameters: total protein (TP), albumin, globulin, creatinine, urea, total bilirubin (TB), g-glutamyltransferase (GGT), aspartate aminotransferase (AST), alanine aminotransferase (ALT). One-way repeated measures analysis of variance (ANOVA) was applied to determine significant effects of time on haematochemical parameters studied. P value <0.05 was considered statistically significant. The results obtained showed a statistical significant effect of time on: total protein (P<0.0001), albumin (P=0.01), globulin (P<0.0001), creatinine (P<0.0001), urea (P<0.0001), total bilirubin (P<0.0001), g-glutamyitransferase (P<0.0001), aspartate aminotransferase (P<0.0001) and alanine aminotransferase (P<0.0001). Our results showed variations in haematochemical parameters related to changes in ambient temperature, relative humidity and temperature-humidity index, although within the physiological range for cattle. Therefore, we can claim that the seasonal variations can influence the metabolic profile of Piemontese cow. These results provide insights into physiological responses of Piemontese cow to different seasons, allowing to better evaluate its ability to adapt and cope with environmental stress.