Some physiological and biochemical methods for acute and chronic stress evaluationin dairy cows

Abstract

Stress factors are so numerous and so diverse in their strength and duration that the consequences on animal welfare can be quite varied. The first important distinction concerns the characterization of acute and chronic stress conditions. Acute stress is a short-lived negative situation that allows a quick and quite complete recovery of the physiological balance (adaptation), while chronic stress is a long lasting condition from which the subject cannot fully recover (maladaptation). In the latter case, the direct effects of the stress factors (heat, low energy, anxiety, suffering etc.), as well as the indirect ones (changes occurring at endocrinological, immune system or function level) can be responsible for pre-pathological or pathological consequences which reduce animal welfare. To evaluate the possible chronic stress conditions in single animals or on a farm (in particular a farm of dairy cows), some parameters of the direct or indirect effects can be utilised. They are physiological (mainly hormone changes: cortisol, β-endorphin), behavioural (depression), biochemical (metabolites, acute phase proteins, glycated proteins etc.), as well as performance parameters (growing rate, milk yield, fertility, etc.). Special attention has been paid to the interpretation of cortisol levels and to its changes after an ACTH challenge. Despite fervent efforts, well established and accepted indices of chronic stress (distress) are currently lacking; but without this objective evaluation, the assessment of animal welfare and, therefore, the optimization of the livestock production, could prove more difficult.

Behavioral and physiological changes in early-weaned multiparous and primiparous beef cows

“…The behavioral stress response was short-lived, as 3 days after weaning most behaviors had returned or were returning to basal frequencies. Although hematological changes lasted longer, this may be related to the normal delay in the response recorded in these parameters (Trevisi and Bertoni, 2009). This suggests that the stress response to weaning is not relevant for cows' welfare in a medium or longtime perspective, irrespective of previous maternal experience.…”

Acute Phase Protein Response during Road Transportation and Lairage at a Slaughterhouse in Feedlot Beef Cattle

“…The direct effects of the stress factors (heat, anxiety, suffering, etc. ), as well as the indirect effects, can be responsible for prepathological consequences that reduce animal welfare [22].…”

Influences of the stress endocrine system on the reproductive endocrine axis in sheep (Ovis aries)

“…A stressor is a stimulus that disrupts homeostasis (Smith & Dobson 2002) and activates a variety of chemical and specific physiological processes and behavioural coping mechanisms to restore homeostasis and promote survival (Cizauskas et al 2015). Acute stress is caused by a short-term negative situation, whereby the individual is able to quickly and completely recover (Trevisi & Bertoni 2009;Papargiris et al 2011). In contrast, chronic stress is defined as a long lasting condition in response to a long-term stressor, whereby the individual may never recover (Trevisi & Bertoni 2009).…”

“…Acute stress is caused by a short-term negative situation, whereby the individual is able to quickly and completely recover (Trevisi & Bertoni 2009;Papargiris et al 2011). In contrast, chronic stress is defined as a long lasting condition in response to a long-term stressor, whereby the individual may never recover (Trevisi & Bertoni 2009). Stress-induced reproductive dysfunction is more likely attributed to chronic stress rather than acute stress and involves neuroendocrine action at the level of the hypothalamus, pituitary glands and gonads.…”