Saint croix sheep stocked on Taiwan grass (pennisetum purpureum) displayed high grazing behavior at noon throughout the year under subtropical conditions in Mexico at 18° N

Abstract

In the tropics, environmental conditions might induce different grazing patterns from those reported in temperate sheep breeds. However, scarce information has been generated on this topic, thus the present study was conducted to analyze the grazing behavior of Saint Croix sheep at 18ºN in Mexico. The present study was carried out using ten adult ewes, 32.8±5.1 kg, stocked on a Taiwan grass (Pennisetum purpurem) pasture maintained at a sward surface height of 30 cm. Observations were conducted during daylight hours (06:00-18:00) from May to April of the next year for three consecutive days every month of the following year. The highest (P<0.05) grazing activity was observed during September (38.9±11.4 min/h), while in May (27.1±14.3 min/h) was the month with least activity (P<0.05). Within days, the highest (P<0.05) grazing activity was observed at 06:00, 12:00 and 18:00 h (34.9±12.0, 31.8±12.9 and 34.5±10.6 min/h, respectively), while 09:00 and 15:00 h (28.6±13.4 and 28.0±15.7 min/h) were the periods with least activity (P<0.05). A correlation of -0.74 (P<0.05) was obtained between environment temperature and grazing activity. It was concluded that Saint Croix sheep, showed monthly pattern throughout the year and displayed high grazing activity at noon along the year, denoting great heat tolerance.