Influence of the short-term road transport stress on blood parameters in cows

摘要

Blood parameter changes have been investigated after short-term road transport stress in 18 crossbred dairy cows in northwest of Iran. Cows were transported in 4 groups of four cows and one group of two cows in five different days. Each group was transported by truck up to a 40 km round trip for an hour. Blood was taken in 5 ml amounts from the jugular vein from each cow before transport and then repeated bleeding at 1.5 hours intervals up to 7.5 hours after transportation. Blood samples were assessed for cortisol, (ELISA), glucose, calcium (Ca), phosphorus (IP), magnesium (Mg) (spectrophotometer method), sodium (Na), potassium (K) (flame Photometer), total protein (TPP), fibrinogen (Refractometer method), leucocytes and differential count. Blood cortisol, glucose and leucocytes count increased up to 340%, 48.6% and 23% within 1.5, 7.5 and 6 hours after transport, respectively. Haematocrit decreased up to 17% after 7.5 hours transport. The mean differences (Wilk's Lambda) for these parameters before and after transport were significant (P < 0.05). The mean differences for Ca, IP, Mg and eosinophil count were also significant (P < 0.05). The highest changes were observed for glucose, hematocrit after 7.5 hours, Ca and the leucocytes count after 6 hours, cortisol after 1.5 hours and the lymphocyte count after 3 hours of transportation. There were significant (P < 0.05) relationships between cortisol&Mg (r = -0.54), cortisol&TPP (r = -0.55), cortisol&fibrinogen (r = -0.52), cortisol&neutrophil (r =-0.52) cortisol & lymphocyte count (r = 0.79) 3 hours after transport. It is concluded that short-term road transport stress increased blood cortisol, that changes in the blood parameters are mainly due to glucose, hematocrit, and leucocyte count and blood electrolytes. Although these changes were within the reference range for cattle, since these parameters are known as health parameters in a ruminant's life they should be considered during the transportation.