Effects of Concentrate to Roughage Ratios on Duration and Frequencies of Rumination and Chewing in Hanwoo Steers

摘要

The effects of concentrate to roughage ratios on duration and frequencies of rumination and chewing in Hanwoo steers were determined. Five Hanwoo steers fitted with rumen fistula were used to evaluate the effects of concentrate to rice straw ratio oneating and ruminating behavior. Experimental diets were formulated with different concentrate to rice straw ratios(50 : 50, 60 : 40, 70 : 30, 80 : 20, 90 : 10). When level of roughage feed was increased by 10, 20, 30, 40 to 50% of total dry matter of the diet total chewing time was increased linearly from 286.99, 321.09, 390.29, 406.63 to 423.30 min/d, which was mainly due to increased ruminating time from 204.91 to 342.80 min/day. However, the level of roughage did not affect eating time. The number of chews per day for rumination and number of chews per rumination were significantly decreased(p < 0.05) as roughage level was increased. In summary, the duration and frequencies of rumination in Hanwoo increased with increased rice straw level.