Evaluation and reduction of influence of stress in fresh dairy cows

Abstract

Introduction Cortisol is known to cause immunosuppression and therefore, increase the risk of infection. High circulating cortisol concentrations were reported to be linked with reduced milk yields (Negrao and Marnet 2003). Stress stimulates the release of adrenocorticotropic hormone from the pituitary gland which promotes the production of the steroid hormone cortisol from the cortex of the adrenal glands. This steroid hormone is more important in altering the body’s metabolism (ie. raising plasma glucose) under conditions of longer term, ongoing (chronic), rather than acute stress (Berci 2002). The aim of this study was to evaluate the impact of stress on the health of fresh-lactation cows. Also to evaluate the effect of NSAIDs on the stress indicator cortisol and somatic cell count (SCC). And to evaluate the effect of stress on the health of fresh-lactation cows from 1 day to 30 days after calving, using the computer herd management program. Materials and Methods There was 600 lactating Lithuanian Black and White cows. Each month there were 40 – 50 calving cows. According to the analogue principle (according to the age of breeding, etc.), 30 cows up to 1 hour after calving were sampled for research. Selected cows were divided into two groups of 15. The testing group of cows (TG), (n=15), were given a subcutaneous injection of Rimadyl Cattle® (50 mg/ml of carprofen) dose were 1.4 mg per 1 kg BW, up to 1 hour after calving. The control group of cows (CG), (n=15) at the same time were given an injection of 0.9 % NaCl. Before the injection of medication, 24 and 48 hours after administration of the drug blood samples were taken to determine plasma cortisol concentration. 1 hour and 30days after calving milk samples were also taken, to determine somatic cell count and milk composition. To assess the effect of stress on the health of fresh-dairy cows, from day 1 to 30 after calving, illness, that usually occu[...].