Stress Response in Dairy Cows Related to Different Blood Glucose

Abstract

MudroÀ P., J. Rehage, H. P. Sallmann, M. Höltershinken, H. Scholz: Stress Response in Dairy Cows Related to Blood Glucose. Acta Vet. Brno 2005, 74: 37-42.The aim of this study was to investigate whether different pre-surgical blood glucose concentrations have any effect on the course of cortisol and metabolic responses to surgical stress in dairy cows. Eighteen Holstein-Friesian dairy cows, admitted for treatment of left abomasal displacement (omentopexy), were used in the study. Abdominal surgery (the stressor) was performed in the standing position 16 -24 h after admission and lasted approximately 60 min. Blood samples were drawn from the jugular vein prior to surgery, immediately after and then 2, 5, 24, and 72 h after surgery. In order to test the effect of the different blood glucose levels on stress responses the experimental animals were allocated to two groups: 1) six hypoglycaemic cows (glucose < 2.4 mmol/l); 2) twelve normoglycaemic cows. Surgery increased blood glucose in both groups (p < 0.001), however, the glucose rise was less distinct in the hypoglycaemic cows. The surgical stress resulted in a significant increase in plasma cortisol concentrations in both groups (p < 0.001), however there was no difference in cortisol responses between the groups. Similarly, surgery enhanced the blood concentrations of free fatty acids (FFA) and L (+)-lactate in both groups (p < 0.001). In contrast, β-hydroxybutyrate concentrations slightly declined after surgery. On the basis of this study there appears not to be any effect of different plasma glucose on the cortisol and metabolite responses in stressed dairy cows. Therefore, it can be concluded that mechanisms regulating peripheral cortisol concentrations, and thus the animal stress response, are more dependent on the intensity of the stressful stimulus than on the energetic status of animal.

Biosynthesis of milk fat, protein, and lactose: roles of transcriptional and posttranscriptional regulation

“…Level of glucose in blood of dairy cows is normally between 3.5 and 4.5 mmol/l (or 63 and 81 mg/dl) in the fasting state during transition from pregnancy to lactation (34) and midlactation (160), respectively, and can reach a level of 5 mmol/l only during disease and/or stress conditions (151) with a maximum of 4.6 mmol/l 6 -10 h after meal (160). The 2.5 mmol/l tested and reported in the above study can be reached only when animals are in a serious hypoglycemic condition (151). In contrast, it is also difficult to increase the availability of glucose in vivo in the mammary epithelial cells to the extent reported in the above study because plasma glucose levels are tightly regulated by homeostatic mechanisms.…”

Cortisol Hormone Concentration and Meat Quality of Beef Cattle Stunned by Captive Bolt Stun Gun before Slaughtering

“…Stress is physiological mechanisms of animal to respond to stress stimuli with minimum alteration in homeostasis (Mudron et al, 2005). According to Okeudo & Moss (2005), stress can be differentiated into physical and psychological stress.…”

Indices of heart rate variability as potential early markers of metabolic stress and compromised regulatory capacity in dried-off high-yielding dairy cows

“…On the other hand, dairy cows experience distinct metabolic stress during periods of high metabolic load and inadequate energy/fuel availability leading to a negative energy balance (NEB), for example, as a result of infectious or metabolic/digestive disorders, during heat stress, and in particular during the transition period around parturition (Gross et al, 2011). Subclinical disorders of the energy metabolism facilitate failure of homeorhetic and homoeostatic adaptations resulting in health problems and reduced performance (Mudron et al, 2005). Therefore, parameters are needed to assess the metabolic status, stress level and regulatory capacity of individual cows and herds.…”

“…Because of the well-known interactions between metabolic stress, nutrition and reproduction, various metabolites (i.e. non-esterified fatty acids (NEFA), β-hydroxybutyrate (BHBA), glucose, lactate) and reproductive hormones are commonly used (Chilliard et al, 1998;Mudron et al, 2005). In addition, the plasma level of cortisol and the heart rate (HR) are applied to assess a stress response and/or the welfare status, and both are known to be influenced by feeding and by the nutritional status (Beerda et al, 2004;Davidson and Beede, 2009;Turbill et al, 2011).…”

“…Also, the SNS and epinephrine are mainly involved in control of protein kinase A-mediated lipolysis during periods of NEB (Chilliard et al, 1998). Together with the adrenocortical axis and behavioural adaptations, the SNS belongs to the main mediators of the stress response (Mudron et al, 2005). Different reactivity/activity of the ANS might thus explain part of the considerable variation in the ability of high-yielding dairy cows to adapt successfully to the metabolic load during pregnancy and onset of lactation.…”