Effect Of Transportation Stress On The Hemogram In Calves
The effect of transportation stress on the hematological parameters of 20 male calves (16 Holstein-Friesian and 4 crossbred), 4 – 10 months old and average in weight of 160 kg was studied. The calves were healthy with no history of any serious diseases.
During an experimental period of 42 days, the calves were kept indoors and fed alfalfa hay and corn silage ad libitum.
After a period of adaptation, on day 21, the first blood samples were taken from all calves in order to have baseline data. Then the calves were divided into three groups: 1- Control group 1 (5 calves) which was kept at stable and had free access to food and water during a 12-hour period of transportation of the experimental group; 2- Control group 2 (5 calves) which stayed at stable but was kept deprived of food and water at the same time; 3- Experimental group (10 calves) which was transported and deprived of food and water too.
On day 26 when transportation began, blood samples were obtained simultaneously from all groups at 0, 1, 3, 6, and 12 hours of transportation. On day 27, blood samples were taken from the experimental group and both control groups. Then on days 31 and 42, blood samples were taken from both experimental and control group 2.
Hematological examination of blood samples revealed that number of R.B.C., W.B.C., neutrophils, and levels of cortisol and P.C.V significantly increased, but lymphocytes and monocytes significantly decreased in the experimental group compared with the control groups (1 & 2) on the day of transportation (P<0.05).
1Expert on Animal Disease Surveillance, Khorasan Veterinary Head Office, Meshed, Khorasan, 91735-744, Iran (Islamic Republic of); 2Shiraz University, School of Veterinary Medicine, FARS, 91735-744, Iran (Islamic Republic of)