Abstrakt: |
Extreme environmental conditions along with calving-associated stress negatively impact the immunity and metabolic functions of the animal. The present study was carried out to investigate the effect of both seasons and transition period on the inflammatory response and metabolic status of 12 periparturient Sahiwal cows, 6 each in the winter (THI= 59.7, comfortable zone) and summer (THI= 81.5, severe heat stress). Blood samples were collected at seven-time points viz., -21, -14, -7, 0, +7, +14, +21 with respect to the days of calving, and harvested plasma samples were used to study the pro-inflammatory cytokines, acute phase protein and energy-related parameters using ELISA. The plasma levels of IL-6, TNF-α and serum amyloid A were higher (p < 0.05) in the summer compared to the winter season. The plasma concentrations of thyroid hormones (T3 and T4) were higher (p < 0.01) in the winter and non-esterified fatty acids (NEFA) were higher (p < 0.01) in the summer irrespective of the days of the transition period. Higher levels of inflammatory biomarkers and NEFA along with lower levels of thyroid hormones in cows calving during the summer season indicate the intensity of physiological and environmental stress experienced by them. [ABSTRACT FROM AUTHOR] |