Effect of season and dietary fibre on feeding behaviour of lactating sows in a tropical climate

Abstract

AbstractTwenty-seven multiparous Large White sows were used to determine the effect of season in a tropical climate and dietary fibre on their feeding behaviour during lactation. The experiment was conducted in Guadeloupe (French West Indies, latitude 16°N, longitude 61°W) between October 1999 and January 2001; climatic conditions in the farrowing room were equivalent to outdoor conditions. Two seasons were determined a posteriori from climatic criteria recorded continuously in the farrowing room. During the warm season, ambient temperature and relative humidity averaged 25°C and 0·868, respectively. The corresponding values for the hot season were 27·5°C and 0·835. Experimental diets offered during lactation were a control diet (C; 140 g neutral-detergent fibre (NDF) per kg) and a high fibre diet (HF; 200 g NDF per kg). Sows were offered food ad libitum between the 6th and the 27th day of lactation. Daily food intake between day 6 and day 27 decreased during the hot season (P < 0·001; 3226 v. 5571 g/d during the warm season). This was achieved by a reduction of both meal size (P < 0·05; 460 v. 718 g per meal) and ingestion and consumption time (P < 0·01; -11·1 and -15·3 min/day, respectively) whereas the number of meals remained constant (8·4 meals per day on average). During warm season, hourly food intake peaked twice daily near sunrise and sunset. During the hot season, peaks were attenuated and food intake was reduced during the hotter periods of the day and increased during the fresher period of the day, especially in early morning. As a result the diurnal partition of food intake was significantly affected by season; proportionately 0·62 and 0·47 of total food intake occurred during the day in warm and in hot seasons, respectively. Standing duration averaged 138 min/ day with no significant difference between seasons. Feeding behaviour criteria were not influenced by diet composition. In conclusion, the season in a humid tropical climate significantly affects the feeding behaviour of lactating sows.