Animal Welfare Indicators in Growing and Fattening Pigs with Different Environmental Conditions

Abstract

The application of different technological innovations in the intensive systems of pig production has generated some problems related to health and animal welfare in modern facilities. To measure animal welfare is necessary to use a set of indicators (behavioural, physiological, productive and sanitary) capable of expressing the animals’ adaptability to the environment. Temperature is one of the main components of the environment, since it influences the physiology, behaviour and productivity of the pigs. The aim of this study is to verify the adaptive evolution to different environmental conditions (winter, thermoneutrality and summer) in growing and fattening pigs through physiological, behavioural and productive indicators. Seven females with initial weight of 45kg were analysed throughout this test. The animals were housed in a room equipped with an environmental control system. The area per animal was 1.5 m2. The environmental data collected were temperature, relative humidity and wind speed. The physiological parameters measured were body surface temperature, rectal temperature and salivary α-amylase. The feed intake was monitored through an individual feed machine equipped with animal weight scale. In order to monitor the behaviour of animals, video cameras and microphones were installed. The final weight of the animals was about 95 kg. The daily food intake and mean daily gain of live weight were 2.70 kg day-1 and 0.611 kg kg-1; 2.51 kg day-1 and 0.947 kg kg-1 and 2.17 kg day-1 and 0.526 kg kg-1, respectively in winter, thermoneutrality and summer. The corresponding values of body surface temperature were 25.4 ºC; 29.1 ºC and 34.0 ºC and the concentration of salivary α-amylase were, on average, 0.33 U/ml; 0.13 U/ml and 0.25 U/ml, respectively in winter, thermoneutrality and summer.