Osmolality is, therefore, an important indicator of the hydration status of the animal (31, 99)

Osmolality is, therefore, an important indicator of the hydration status of the animal (31, 99). The dehydration status of a calf might be related with an increased likelihood to develop diseases at the veal farm (27). different risk groups after arrival. By adopting treatment decisions and protocols on a risk-group or individual basis, it would be possible to improve animal health and reduce both disease incidence and antibiotic use. Moreover, the use of biomarkers might be an economically feasible approach as some of them do not need invasive techniques as well as others can be measured in blood already taken during routine checks. Previous literature mainly assessed the physiological responses of calves to transportation. However, information on the link between on-farm introduction data and future health and overall performance of veal calves is limited. This review, therefore, examined a wide range of papers and aimed to identify potential biomarkers of future health and overall performance. sp., and rotavirus are the most common microorganisms, causing enteric diseases and diarrhea in young calves (19). In an attempt to counteract the negative effects of diseases, the use of therapeutic treatments has become widespread (20). The use of antimicrobial growth promoters has been banned in Europe since 2006 (21), but since then the use of therapeutic antimicrobials increased (22). A recent study exhibited that antimicrobial use in veal N-Acetyl-D-mannosamine calves is the highest of N-Acetyl-D-mannosamine all food producing animals (10). Pardon et al. (23) reported that in Belgium the antimicrobial consumption in white veal calves is usually approximately 25.2 tons per year. In the Netherlands, one of the main veal generating countries in Europe, that has comparable veal production systems as Belgium, a reduction in antimicrobial use in veal production has already been achieved during recent years. However, the usage of antimicrobials is considered still high (10, 24). There is growing public concern about the consequences of feeding antibiotics (especially oral treatments) to farm animals, including veal calves, COL1A1 for both human and animal health (e.g., a massive use of antibiotics may cause antibiotic resistance) (20, 25). Therefore, there is a strong need for management strategies in the veal sector that may help to reduce the incidence of diseases and, consequently, antibiotic use. Clinical power of potential biomarkers in veal calves: future implications This review builds on the idea that response variables obtained in calves on introduction at the veal farm may be used as predictors or biomarkers of later health and overall performance. A biomarker, per definition, is usually a marker of a biological process or state and it can provide information on a current status or future risk of disease of an individual (26). The availability of such biomarkers would be helpful, for example, to identify individual calves at an early stage with an enhanced probability to develop disease, and to take preventive steps before clinical problems occur. At herd level, biomarkers might be utilized for profiling calves according to the magnitude of stress they have experienced and their predisposition to develop future diseases (27). Grouping of calves in different risk groups should help the farmer in managing calves at introduction. By adopting handling procedures, treatment decisions and protocols on a risk-group or individual basis, farmers might be able to better meet individual animal needs and improve the health and welfare of calves throughout the veal production chain [observe also Renaud et al. 28). Collectively, this may reduce the incidence of disease as well as the use of antibiotics. Previous studies (29C32) examined effects of different transport conditions and duration on calf blood constituents and overall performance of calves at their introduction at the N-Acetyl-D-mannosamine veal farm. Only a limited number of studies (30, 33, 34) assessed associations between on-arrival blood constituents and future overall performance of calves at the veal farm. By examining a much wider range of papers, this review aimed to identify potential on-farm biomarkers of health and overall performance of calves at the veal farm. Effects of environmental difficulties on physiological pathways and on biomarkers Environmental difficulties, including road transportation, are known to impact metabolic (35), physiological (36), immunological (37C39) and behavioral responses (36, 40) of calves. As illustrated in Physique ?Determine1,1, exposure of the animal to environmental challenges can be short-term or prolonged. In both cases, an increase in plasma concentrations of glucocorticoids and cortisol is usually observed. In case of short exposure, a peak production in glucocorticoids determines an acute stress response. As a result, a calf might experience changes in its biological functions, with shifts in energy sources that allow the animal to better cope with the stressor. Moreover, an activation of the immune system, including enhanced cell function, cell-mediated, humoral and innate immunity, might protect calf health (41). All these changes might restore homeostasis in the short-term and not impact animal health and welfare on the long run. In case of prolonged exposure, prolonged higher concentrations of glucocorticoids may lead to prolonged/chronic stress response (Physique ?(Figure1).1). Under these circumstances, the activation of the hypothalamic-pituitary-adrenal (HPA) axis is responsible for N-Acetyl-D-mannosamine long-lasting effects on the animal.