Changes in collagen, texture and sensory properties of meat when selecting rabbits for growth rate M. Pascual * , M. Pla Institute for Animal Science and Technology, Polytechnic University of Valencia. P.O. Box 22012, 46071 Valencia, Spain Received 7 November 2006; received in revised form 8 June 2007; accepted 2 July 2007 Abstract The consequences of selection for growth rate and the associated decrease of maturity at slaughter in rabbits on collagen content, collagen solubility, meat texture (Warner–Bratzler shear device) and the sensory properties of the m. Longissimus were studied. Sixty rabbits from the 7th generation of a line selected for growth rate (group C) were compared to 60 rabbits from the 23rd generation of the same line (group S). Both groups were contemporarily reared and slaughtered at 2000 g. No changes on collagen content were found, but group S had a higher (5%) collagen solubility. Shear force, shear firmness and area or total work needed to cut the sample were not different between groups, and hardness evaluated in the panel test was not relevantly changed. Most of the sensory properties studied did not differ relevantly between groups. Group S had 8% less aniseed odour and 10% more juiciness. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Selection; Collagen; Texture; Sensory analysis; Rabbit; Bayesian analysis 1. Introduction Rabbit meat is usually produced by a three-way cross, where females from a cross of two lines selected for repro- ductive traits are mated with males from a line selected for growth rate. There are few studies on how this selection affects meat tenderness, which is usually determined by mechanical procedures or sensory analysis, and results are not clear. Ramı ´rez et al. (2004) and Gil et al. (2006), comparing rabbits selected for growth rate with a control population, observed an increase in the shear firmness in the selected rabbits, which indicates more resistance of the meat to cutting. Gumminess, chewiness and hardness also increased. Gondret, Combes, Larzul, and Rocham- beau (2002), in an experiment involving divergent selection for weight at slaughter age, observed higher values of the maximum shear force and total energy needed to cut the meat in the rabbits selected for high body weight compared to those selected for low body weight. Conversely, Larzul, Gondret, Combes, and Rochambeau (2005) found a lower value of the maximum shear force in animals selected for high body weight at slaughter compared to those from a control group from the same line. Only Herna ´ndez et al. (2005) studied the effects of selection for growth rate on the sensory properties of the rabbit meat. No differences were found in texture, juiciness and fibrousness. Liver fla- vour was relevantly higher in rabbits selected, to the detri- ment of the aniseed odour and flavour. Taylor (1985) suggested comparing animals from differ- ent species or breeds at the same stage of maturity, in order to avoid differences due to the different physiological age. For this reason, the articles cited above on the effects of selection for growth rate compared selected and control groups at a similar age, which corresponds to a similar degree of maturity (Blasco, Piles, & Varona, 2003; Pla, Piles, & Valdevira, 1997). However, the selection for growth rate in rabbits increases the adult weight (Blasco et al., 2003). Thus, at the weight fixed by the market, the animals selected for growth rate have a lower degree of 0309-1740/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.meatsci.2007.07.009 * Corresponding author. Tel.: +34 9638 79438; fax: +34 9638 77439. E-mail address: ampasam@dca.upv.es (M. Pascual). www.elsevier.com/locate/meatsci Available online at www.sciencedirect.com Meat Science 78 (2008) 375–380 MEAT SCIENCE