PAPERS & ARTICLES- Effects of vehicle movements during transport on the stress responses and meat quality of sheep J. L. RUIZ-DE-LA-TORRE, A. VELARDE, A. DIESTRE, M. GISPERT, S. J. G. HALL, D. M. BROOM, X. MANTECA Two groups of 26 lambs were transported for 15 hours either on smooth highways or on rougher secondary roads. Nine of the animals in each group were monitored for heart rate and the plasma levels of cortisol, creatine kinase and lactate dehydrogenase, before the journey began, after four, eight and 12 hours and at slaughter. The pH of the meat was measured 45 minutes and 24 hours postmortem and its colour was assessed 24 hours postmortem. The lambs transported on smooth roads had a lower heart rate and lower plasma cortisol concentrations after eight and 12 hours than the lambs transported on rougher roads. Twenty-four hours after slaughter the pH of the meat of the lambs transported on smooth roads was lower than that of the lambs transported on rougher roads. Veterinary Record (2001) 148, 227-229 J. L. Ruiz-de-la-Torre, BVSc, PhD, A. Velarde, BVSc, X. Manteca, BVSc, PhD, Departament de Biologia Cellular, Fisiologia i Immunologia, Facultat de Veterinaria, Universitat Aut6noma de Barcelona, 08193 Cerdanyola del Valles, Spain A. Diestre, BVSc, PhD, M. Gispert, BVSc, Centre de Tecnologia de la Carn, Institut de Recerca i Tecnologia Agroalimentaries, Granja Camps i Armet, 17121 Monells (Girona), Spain S. J. G. Hall, BVSc, PhD, D. M. Broom, DVSc, Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES THE transport of live animals has important implications on both economic and welfare grounds (Grandin 1993). Economic losses during transport are due to mortality, par- ticularly of pigs and poultry, carcase bruising and shrinkage (loss of weight) and reductions in meat quality (Warriss 1996). Dark, firm, dry (DFD) meat occurs regularly in pigs and cattle (Tarrant 1981), and is mostly related to fighting, although ani- mals that are not directly involved in fights but which are threatened may also develop DFD (Tarrant and Grandin 1993). Sheep have been reported to develop DFD meat (Apple and others 1995), but little is known about the factors involved in its development while they are being transported. The to and fro movements induced in the animals by the movement of the vehicle can cause motion sickness (Nicol and Saville-Weeks 1993). The incidence of DFD meat is related to a lack of glycogen for energy provision before slaughter. The effort needed by the animals to keep their balance while the vehicle moves may be demanding in terms of energy requirements and increase the incidence of DFD meat (Tarrant and Grandin 1993). Furthermore, the vibration and move- ment of the vehicle are unfamiliar to the animals, and are therefore likely to elicit a stress response (Dantzer and Mormede 1983). The aim of this experiment was to study the effects of the movement and vibrations of the transport vehi- cle on the stress responses and meat quality of the sheep being transported. MATERIALS AND METHODS Fifty-two 10- to 12-week-old lambs (26 males and 26 females) of the Ripollesa breed (a mutton-type sheep) and weighing approximately 20 kg were used. Before being transported the sheep were housed singly in pens 4 m2 in area. The vehicle used in the experiment is shown in Fig 1. A tri-axial accelerometer linked to a multichannel data-logger (EDR-1; Squirrel Grant) was used to record any movement of the vehicle with an acceleration greater than 7 m/s2 (Broom and others 1996). Two journeys were made, one involving driving on smooth highways and one involving driving on rougher secondary roads. Each journey lasted for 15 hours, including three stops of about 30 minutes each. Twenty-six lambs (13 males and 13 females) were used on each journey and the stocking density on the vehicle was about 0-26 m2/animal. This stocking den- sity is within the range permitted by the European Union directive for the transport of live animals (95/29/EC). The percentage of the animals standing was recorded every 10 minutes using a videocamera (CCD-VXI-E; Sony) with an intervalometer (to record changes in acceleration). Nine of the animals on each journey were randomly selected for mea- surements of heart rate, and the plasma concentrations of cortisol, creatine kinase (CK) and lactate dehydrogenase (LDH). Heart rate monitors were strapped on to the bodies of the sheep and their heart rates were later transferred to an electronic reading device (Polar Sport Advantage monitors; Polar). Blood samples were taken from each of the nine animals immediately before the journey, when the vehicle stopped after four, eight and 12 hours, and also when they were slaughtered. The levels of CK and LDH were analysed spec- trophotometrically by standard methods recommended by the International Federation of Clinical Chemistry (Anon 1972, Gruber 1978). Plasma cortisol levels were analysed with a commercial radioimmunoassay (Fenzia kit; Orion Diagnostica). After the journey the animals were electrically stunned (head-only at 350 V for three seconds) and bled out. After slaughter, the pH of the longissimus dorsi muscle was mea- sured after 45 minutes and 24 hours with a pH meter (Scharlau with xerolyt electrode). The colour of the meat was recorded at the internal face of the rectus abdominis muscle on the carcase, with a colorimeter (CR-200; Minolta) and deter- mined in terms of three parameters: a (redness), b (yellow- ness) and L (paleness). Statistical analysis The percentages of the animals standing, the heart rates and the plasma levels of cortisol, LDH and CK were compared by using the Mann-Whitney U test. The parameters of meat quality were compared by using Student's t test. All the analy- ses used the sPss - Statistical Package for Social Sciences - program v 8.0. RESULTS Differences in driving conditions There were fewer changes in acceleration of more than 7 m/s2 every 30 minutes during the journey on smooth highways than during the journey on secondary roads; the mean (sd) numbers were 0 75 (0-13) and 15 1 (3.2) (P<0.005). Effects on numbers of animals standing and heart rate On average, a smaller proportion of the animals remained standing during the smooth journey than during the rough The Veterinary Record, February 24, 2001 227