Stress hormones, carcass composition and meat quality in Large White · Duroc pigs A. Foury a , N. Devillers a , M.-P. Sanchez b , H. Griffon c , P. Le Roy b , P. Morme `de a, * a Laboratoire de Neuroge ´ne ´tique et Stress, Institut National de la Recherche Agronomique, Universite ´ Victor Segalen Bordeaux 2, Rue Camille St-Saens, 33077 Bordeaux Cedex, France b Station de Ge ´ne ´tique Quantitative et Applique ´e, Institut National de la Recherche Agronomique, 78352 Jouy-en-Josas, France c Domaine Expe ´rimental du Magneraud, Institut National de la Recherche Agronomique, 17700 Surge `res, France Received 5 August 2004; received in revised form 1 October 2004; accepted 1 November 2004 Abstract The levels of stress hormones, cortisol and catecholamines (adrenaline and noradrenaline), were measured in urine collected after slaughter from the bladder, in 309 pigs (females and castrated males) from an F2 intercross between the Large White and Duroc breeds to analyze the relationships between stress-responsive neuroendocrine systems, carcass composition and meat quality. Intra- muscular fat content was measured from a biopsy sample taken at a live weight of 70 kg from the longissimus lumborum muscle, and carcass and meat quality traits were also collected. Carcass fat content was higher and estimated carcass lean meat content was lower with increasing urinary levels of cortisol and adrenaline (that are highly correlated with each other), but was not related to the levels of noradrenaline, showing that adrenal hormones favor the accretion of fat at the expense of muscle proteins, a typical physiological effect of cortisol. On the contrary, intramuscular fat levels were unrelated to either hormone level. Finally, muscle pH measured 24 h after death was positively correlated with catecholamine levels, an effect related to the catabolism of muscle glycogen by catechol- amines released by preslaughter stress, which impairs post-mortem acidification of meat. These results show the importance of a control over stress neuroendocrine systems to increase pork production and product quality, and the value of the genetic approach to reach this goal. Ó 2004 Elsevier Ltd. All rights reserved. Keywords: Cortisol; Catecholamines; Urine; Adiposity; Intramuscular fat; Meat pH 1. Introduction The two main stress-responsive neuroendocrine sys- tems play a critical role in the regulation of energy fluxes. The hypothalamic–pituitary–adrenocortical (HPA) axis influences feeding behavior, pancreatic hor- mone secretion, energy expenditure and the protein/lipid balance (Dallman et al., 1993). Altogether, cortisol, the main active hormone of the axis, released by the adrenal cortex, favors the accretion of fat at the expense of pro- teins (Devenport, Knehans, Sundstrom, & Thomas, 1989). Indeed, pig breeds with a higher carcass content of fat like Meishan (Bidanel, Caritez, Gruand, & Lega- ult, 1993) or Duroc (Smith & Pearson, 1986) also pro- duce more cortisol (Bergeron, Gonyou, & Eurell, 1996; De ´saute ´s, Bidanel, & Morme `de, 1997; De ´saute ´s, Sar- rieau, Caritez, & Morme `de, 1999; Hay & Morme `de, 1998; Morme `de et al., 2004; Weiler, Claus, Schnoebe- len-Combes, & Louveau, 1998). On the other hand, cat- echolamines (adrenaline and noradrenaline) released by the sympathetic nervous system (SNS) increase the use of energy stores (glycogen and lipids; Scheurink & 0309-1740/$ - see front matter Ó 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.meatsci.2004.11.002 * Corresponding author. Tel.: +33 5 57 57 37 53; fax: +33 5 57 57 37 52. E-mail address: mormede@bordeaux.inserm.fr (P. Morme `de). www.elsevier.com/locate/meatsci Meat Science 69 (2005) 703–707 MEAT SCIENCE