The effects of particle size of two forages on rumen parameters, chewing activity and feed intake of lactating sangsari ewes

An experiment was carried out to evaluate the effects of particle size of two forages on rumen parameters of ten Sangsari fistulated lactating ewes using a complete randomized design with five treatments in six replications during 30 days.Experimental rations includes 1) coarse alfalfa犆ꮱ corn silage 2) medium alfalfaઆꮱ corn silage 3) medium alfalfa 縩 corn silage 4) Fine alfalfa犆ꮱ corn silage 5) Fine alfalfaᘩ corn silage. The ruminal content of ewes manually evacuated at 3, 7.5, and 12 h post feeding and seprated to particulate and liquied phase. The chemical composition of feed ingredients and experimental rations were similar but particle size of forages was different among treatments. Along with decrease of particle size, pef>8 decreased significantly. Also, reduction of particle size decreased the value of pef>1.18 in alfalfa and corn silage. Geometric mean of particles was decreased significantly with decrease of particle size, but standard deviation of geometric mean was tended to significance. Consumption of neutral detergent fiber was not affected by forage particle size. Geometric mean of solid particle size in rumen at different hours after feeding did not show significant difference. Along with increase of time after feeding, portion of passable phase particles from rumen was increased. Feeding activity and total chewing time were not affected by experimental treatment, but as was expectable along with decrease of particle size, rumination time was decreased significantly.