Seasonal changes in diet selectivity and grazing behaviour of goats on semi-arid rangeland

Dietary preference and grazing behaviour of male Kutchi goats grazed on sem i-arid rangeland were continuously monitored from 08: 00 to 17: 00 hr, duri ng monsoon, winter and summer. Crude protein (CP), neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents of pasture were 9.94, 72.45 a nd 52.86 % in monsoon, 7.19, 67.76 and 54.42 % in winter and 6.61, 73.75 an d 64.55 % in summer, respectively. CP content of diet in monsoon was 13.40 %, which slightly declined to 12.78 % in winter, and again increased to 14. 84 % in summer. Preference index (PI) for CP progressively increased from 1 .35 in monsoon to 1.78 in winter and 2.25 in summer. Grazing period was 7.4 1 hr in monsoon, 8.46 hr in winter and 8.07 hr in summer, and it was negati vely correlated with ambient temperature (r = -0.76) and relative humidity (r = -0.34). Masticating rate (chew/min) was almost similar in 3 seasons an d average value was 76. Ruminating rate was 1.44, 1.11 and 1.08 in monsoon, winter and summer, respectively. The bipedal stance was lowest in monsoon (0.52), highest in winter (2.86) and intermediate in summer (1.25). It is c oncluded that goats grazing on semiarid rangeland select quality nutrients with deterioration of pasture condition and alter behavioural pattern to mi nimize the environmental stress.