THE EFFECT OF BODY CONDITION ON THE FEEDING-BEHAVIOR OF SHEEP WITH DIFFERENT TIMES OF ACCESS TO FOOD

Intakes and feeding patterns were studied in two groups of 24 Scottish Blackface ewes, with initial mean body condition scores of 2.15 (thin ) and 3.15 (fat). Three treatments, allowing access to a dried-grass p ellet diet ad libitum for 6, 12 or 24 h/day, were applied in a Latin-s quare design, with each sheep receiving each treatment for one 12-day period. Food intakes were measured daily and feeding activity was reco rded automatically every minute for one 24-h period during the last 5 days of each 12-day treatment period. Mean intakes were higher for thi n than for fat ewes (1720 v. 1467 g dry matter (DM) per day; P < 0.001 ). There were no interactions between the effects of body condition an d food access time and mean intakes over the last 7 days for the 6-, 1 2- and 24-h food access treatments were 1429, 1686 and 1805 g DM per d ay respectively (P < 0.001). Time spent feeding was higher for thin th an for fat ewes, over the whole day (231 v. 197 min/day; P < 0.05) and in the first 6 h after the introduction of fresh food (140 v. 120 min ; P < 0.05), but there were no differences between thin and fat ewes i n the frequency of meals or in the rate of intake during meals. Intake s for the first 6 h were higher with restricted food access (1402, 110 9 and 819 g DM per clay for 6-, 12- and 24-h access; P < 0.001) but th ere were no differences in time spent feeding. The number of meals dur ing the fir st 6 h was higher (10.4 v. 8.3; P < 0.51 and the rate of i ntake was higher (11.4 v. 7.8 g/min; P < 0.05) for 6-h compared with 2 4-h food access. It was concluded that long-term differences in intake due to body condition and short-term changes due to restricting food access time, involve different behavioural responses and this may refl ect differences in the mechanisms involved in the regulation of volunt ary intake.