Effect Of Roughage Particle On Behavior,Rumen Fermentation And Production Performance Of Sheep

Studing the effect of roughage particle on behavior,rumen fermentation and production performance of sheep,has important practical significance for guiding the rational processing of roughage and making full use of roughage to improve animal performance.This study uses a combination of field observations,analytical determination in the laboratory,digestion and metabolism tests,and feeding tests.Test 1: Effect of roughage particle on behavior of sheepUsing a single-factor randomized trial design,divided thirty-six healthy sheep with similar body weights into 3 groups with 3 replicates and 4 sheep per replicate.Each group was fed diets consisting of 1 cm,2 cm,and 3 cm wheat straw on the basis of quantitative feeding of concentrate supplements,feeding for 40 days.The results show:(1)With the increase of the length of roughage,the feed intake and NDFI showed a linear downward trend(R2 = 0.9969,P=0.07).(2)Increase the length of roughage,animal feeding time increased(P <0.05),ruminant time and chewing time was increased first and then decreased,feed rate is significantly reduced,the rate of rumination rate is decreasing and then rising,chewing rate is reduced(P <0.05).(3)Reducing the length of roughage can significantly increase the rest time(P<0.05)and decrease the standing time(P<0.05).Test 2: Effect of roughage particle on rumen fermentation of sheepSelect three small-tailed sheep with good body condition,similar body weight,and permanent rumen fistula as experimental animals.Each group was fed diets consisting of 1 cm,2 cm,and 3 cm wheat straw on the basis of quantitative feeding of concentrate supplements,adopt 3 × 3 Latin square design for a 3-phase feeding trial.Collect the ruminal fluid at 2h,4h,6h,8h,10 h,and 12 h after the formal diet,and measure the pH,volatile fatty acid content,and NH3-N concentration.The results show:(1)In 1cm group,2cm group and 3cm group,the change of pH within 12 h is first rising and then falling.With the gradual increase of wheat stalk comminuted length,the pH of the rumen gradually became stable after ingestion;the pH at each time and the average pH point showed the regularity of "1cm group <2cm group <3cm group".(2)In the three experimental groups,the changes of acetic acid,propionic acid,butyric acid and total volatile fatty acids(TVFA)in the rumen all showed a “first increase and then decrease” in 12 hours.;the acetic acid/propionic acid and its average value showed the regularity of "1cm group<2cm group<3cm group" at each time point(P<0.05).(3)In the three experimental groups,the concentration of NH3-N in the rumen showed a trend of “decrease first and then increase” within 12 hours.As the grain size of wheat straw increased,the average concentration of NH3-N in the three experimental groups increased in turn(P<0.05).Test 3: Effect of roughage particle on production performance of sheepDivided thirty-six healthy sheep with similar body weights(37.13±3.12kg)into 3 groups,each group was fed diets consisting of 1 cm,2 cm,and 3 cm wheat straw on the basis of quantitative feeding of concentrate supplements,feeding for 40 days(prefeed period 10 days).The results show:(1)With the gradual increase of the crushed grain size of wheat straw,the feed intake of wheat straw and diet showed a linear decreasing trend(P=0.09).(2)As the length of roughage gradually increased,the digestibility of dietary DM,NDF and ADF decreased linearly(P<0.01),while the protein digestibility showed an upward trend(P=0.07).(3)With the decrease of the length of roughage,the production performance and feed conversion efficiency were significantly increased(P<0.05),and the economic benefits were significantly improved(P<0.01).(4)The optimum feed length for roughage is 1cm...