Effects of transport and handling on animal welfare, meat quality and environment with special emphasis on tied cows
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Transport of slaughter animals has been intensified in the recent years in Sweden. In connection to rationalization and re-structuring, many abattoirs closed down in the last decades. This implies that the animals should be transported greater distances. During transport from farms to abattoirs, animals may be subjected to un-favourable conditions leading to a compromise of animal welfare and reduced meat quality. An increase of transport work also contributes to the environmental degradation in terms of air emission emanated from the vehicle. Hitherto little or no attention has been made to optimize the transport work. Important research works have been made to determine the effect of transport and handling on meat quality. However, limited attention has been paid to a comprehensive work to determine the main factors causing stress on animals by making continues measurement. The current paper reports the results of study made on transport of tied cows between farms and Scan Farmek’ s abattoir in Uppsala region. The main purpose of the study was to gather pertinent information which may enable to assess the transport system in detail and to develop an effective transport and logistic system using information technology to promote economy, animal welfare and environment. The specific objectives were to identify main factors which may cause stress on animals during handling and transport, to simulate and optimize transport routes and to determine air emissions from the vehicle to estimate the environmental impact. The measured parameters were heart rate; pH, lactate concentration, muscle glycogen, vibrations (in tri-axial directions), temperature in the pens, vehicle’s speed, transport route and locations of farms in relation to abattoirs using the satellite steered Global Position System (GPS). The alteration of animal behaviour was also recorded using a video camera mounted in the pen. The results indicated that loading of animals at the farms, transport on rough and curved roads, variation of vehicle’s speed, mixing of animals with un-familiar animals from other farms and un-loading at the abattoir are the main events which caused significant increases of heart rate. Urination, defecation, exploration and mooing were the usual behaviour observed during loading and un-loading. The animals lost their balance and rocked during the initial motion of the vehicle and while driving on rough and curved roads. Samples for pH were taken at 45 minutes, 12 hours and 24 hours after slaughter. The result showed that pH decreased rapidly up to 12 hours and decreased slowly thereafter and maintained steady state before 24 hours. The measured pH values could be described using an exponentially decaying type of equation. About 20% of the animals had the final pH value (measured 24 hours after slaughter) above 5.8. Concentration of lactate was measured both in plasma and muscle. Blood samples were taken before and after transport and the concentration increased by the factor of 1.03 to 4.22 after transport. The measured vibration data was subjected to spectral data analysis to determine the main resonance frequencies. The identified resonance frequencies are at about 1.3, 3, 6, l2, 25 and 40 Hz. The first two frequencies are typical for animal transporting trucks. The variation of resonance frequencies depended on vehicle’s speed and road type and further investigations should be made to scrutinize the effect of the identified frequencies on animals. Investigation on the effect of vibration magnitude on heart rate and pH-value showed that an increase of r.m.s acceleration by about 5 times caused an increase of heart rate by 80% and the meat pH-value of those animals transported on rough and curved roads was above 5.8. However, further comprehensive investigation is required to determine the effect of vibration on the final pH of meat. The route planning and optimization for each journey was made using a network software, DPS. Route optimization decreased the actual transport distance by 8% to 14%. Air emissions such as CO2, CO, HC and oxides of nitrogen from the vehicle were computed using MODTRANS, the model developed for food distribution and environmental research. Route planning could reduced air emissions by 10% to 18%. The current work recommends to carry out detailed investigations on the effect of transport length and vibration on heart rate and meat quality of various categories of animals. Application of route planning is also recommended to reduce the transport distance.