Effects of castration, tooth resection, or tail docking on plasma metabolites and stress hormones in young pigs1

Abstract

Changes in the activity of the sympathetic nervous system or in the hypothalamo-pituitary-adrenal axis have been extensively used to evaluate pain induced by castration or tail docking in numerous species. Such data are missing in pigs. Therefore, three experiments were conducted to determine the effects of castration, tail docking, or tooth resection on stress hormones. Glucose and lactate also were measured because catecholamines stimulate mobilization of glycogen, which results in glucose and lactate release. In Exp.1, 18 male pigs from seven litters (two or three pigs per litter) were catheterized surgically into one jugular vein, under general anesthesia, at 5 or 6 d of age. Two days later, they were submitted either to bilateral castration, control handling, or no handling (n = 6 per group). Blood samples were collected before (- 15 and -2 min) and after (5, 15, 30, 60, 90, 180 min) the experimental treatment. In Exp. 2, 27 female pigs from 12 litters (one to four pigs per litter) were submitted either to tooth clipping with pliers, tooth resection with a grinder apparatus, control handling, or no handling (n = 6 or 7 per group) at 1 d of age. In Exp. 3, 17 female pigs from nine litters (one to three pigs per litter) were submitted to one of the following treatments: 1) tail docking with an electric-heated scissor docking iron, 2) control handling, and 3) no handling (n = 5 or 6 per group) at 1 d of age. Castration induced significant (P < 0.05) increases in adrenocorticotropin hormone (ACTH; from 5 to 60 min), cortisol (from 15 to 90 min), and lactate (from 5 to 30 min). These variations are indicative of stress and tissue damage following castration. In contrast, neither tail docking nor tooth resection had marked effects on plasma cortisol, ACTH, glucose, and lactate. Measurements of plasma cortisol, lactate, and ACTH could be useful for validating treatments designed to relieve the distress reaction induced by castration in pigs.

Influence of production system in local and conventional pig breeds on stress indicators at slaughter, muscle and meat traits and pork eating quality

“…This indicates that responses of pigs to pre-slaughter handling did not differ between B and LW breeds in our C and A experimental conditions. The higher plasma lactate concentrations of the LW pigs indicate higher mobilization of muscle or liver glycogen stores during the pre-slaughtering period, in response to stress (Prunier et al, 2005) or due to higher physical exercise (Fernandez et al, 1995), although other indicators of stress (e.g. cortisol) or muscular activity (CK and LDH) did not differ between breeds.…”

“…Pre-slaughter stress was assessed through levels of plasma ACTH and cortisol, which is synthesized under the control of ACTH and released into the circulatory system 20 to 30 min after an acute stimulation (Prunier et al, 2005). Global energy metabolism was evaluated by determining plasma glucose and lactate levels, which indicate the balance between mobilization and use of energy primarily for muscle activity and the intensity of anaerobic metabolism, respectively (Lebret et al, 2006).…”

Influence of housing and season on pubertal development, boar taint compounds and skin lesions of male pigs

“…Fat deposition is favoured at the expense of protein deposition, which decreases carcass leanness and hence its value. Furthermore, surgical castration is ethically questionable because it generates severe physiological and behavioural signs of pain (Hay et al, 2003;Prunier et al, 2005). Therefore, surgical castration is highly debated in the European countries, and numerous stakeholders in the pig industry have committed themselves to abandon this practice by 2018, provided that solutions regarding the boar taint problem are found.…”

Physiology and behavior of pigs before and after castration: effects of two topical anesthetics

“…However, the procedure of surgical castration causes acute pain-induced distress, which is an animal welfare concern (McGlone et al, 1993;Prunier et al, 2005;Carroll et al, 2006). Negative public perception concerning castration without the use of analgesics or anesthetics is increasing (Giersing et al, 2006;Svendsen, 2006 include slaughtering pigs before they reach sexual maturity (Dunshea et al, 2001), using immunocastration techniques, sperm sexing for selection of female offspring and genetic selection for pigs with low levels of boar taint.…”