Assessment of transport stress on cattle travelling a long distance (˜648 km), from Jessore (Indian border) to Chittagong, Bangladesh

Alam, Mahabub; Hasanuzzaman, Md; Hassan, Mohammad Mahmudul; Rakib, Tofazzal Md; Hossain, Md Emran; Rashid, Md Harun; Sayeed, Md Abu; Philips, Lindsay B; Hoque, Md Ahasanul

hormone) insignificantly increased after transportation (4 µg/dl before to 4.8 µg/dl after) in the present study. The similar results are reported by a number of previous studies. 4 51 This particular trend could be explained by the variable duration of transportation time. The level of cortisol increases to peak at 1.5-4 hours of transportation and then gradually decreases with the increase of transportation time due to the negative feedback to the hypothalamus by the initial peak concentration of cortisol in serum. 60 61 However, many earlier studies found cortisol elevation at a significant level after transportation, such as 10 ng/ml (before) to 22 ng/ml (after), 55 and 4.8 ng/ml (before) to 15 ng/ml (after). 62 The mechanism behind the increase of blood cortisol level can be explained as signals, originating from stress such as long-distance transportation, are transmitted to the hypothalamus, activating HPA and sympathoadrenal axes. The HPA axis affects perception in the brain, Alam resulting in the release of the hypothalamic factor, corticotrophin-releasing factor and vasopressin, which in turn stimulates the anterior pituitary gland to secrete adrenocorticotropic hormone (ACTH). The ACTH circulating in the blood stimulates the adrenal cortex to surge of cortisol secretion. 5 63 64 limitations of the current study Selection bias might be introduced as the sample size for the study was not calculated based on statistical assumptions and random sampling was not always followed.