Influence of Particle Size on the Effectiveness of the Fiber in Barley Silage

Abstract

We used eight multiparous Holstein cows in a 4 x 4 Latin square design to evaluate the effects and possible interactions between silage particle size and concentrate level on chewing activities and productivity of cows fed barley-based total mixed rations (TMR). Diets were designed with two forage-to-concentrate ratios (low forage, 45:55, high forage 55:45), combined with two theoretical chop lengths of barley silage (short = 4.68 mm and long = 18.75 mm). Diets were formulated to provide similar and above-minimum neutral detergent fiber recommended for cows in early lactation. Increasing silage particle size of the forage did not affect dry matter intake. The 3.5% fat-correct milk and fat yields trended higher for increased particle size. Percent milk protein was higher for short particle size. Increasing the concentrate levels in the diets increased proportions of milk protein and lactose, but not milk fat. Cows fed short silage spent 90 min less per day chewing and ruminating than did those on long silage. Total chewing activity per kilogram of forage intake was higher for cows on long silage compared with those on short silage diets. Although a reduction in silage particle size did not depress milk fat, rumination and chewing activity were significantly reduced. These results suggest that particle size of the silage may have dominant control over chewing activity despite adequate neutral detergent fiber intakes.

Effects of barley silage particle size and concentrate level on rumen kinetic parameters and fermentation patterns in steers

“…The most common reasons for the drop in rumen NH 3 concentration are explained by a reduction in the degradability of feed proteins. In our earlier experiment using barley silage with similar particle size, chewing activity was reduced when diets containing short barley silage were fed (Soita et al 2000). This may have decreased saliva production and therefore recycling of blood urea via the saliva; however, our results clearly show ammonia concentrations were above minimum requirements.…”

Effect of corn silage particle size and level of soybean oil on ruminal mat composition, distribution and consistency in Zel sheep

“…Therefore, increased chewing activity in the fine corn silage diets (per kg peNDF) was due to more rumination on fine corn silage diets. But Soita et al (2000) reported that reducing corn silage particle size of 19 to 13 mm has little effect on chewing activity, but decreasing from 13 to 6 mm caused 30% of the chewing activity to decrease. It could be that part of the differences between hay in stimulating chewing activity was due to the differences in forage particle size, density and the physical interaction with other feeds in the rumen.…”

“…Yansari et al (2004) found that reducing alfalfa hay particle size in cow diets of 19 to 10 and 2 mm, the time consumption declined per kg DM and NDF. Soita et al (2000) reported that comparison between four diets with two levels of particles size and two levels of concentrate particle size had a high significant effect on time consumption and time consumption per kg of forage and NDF intake. In the experiment of Schwab et al (2002), time consuming (minutes per day) and consumption (min) per kg DM and NDF intake did not decrease significantly in corn silage with size 18 mm vs. 32 mm; but differences were significant between diets containing corn silage with a theoretical cut length of 13 mm vs. 19-mm per kg DM.…”

Comparação da fibra em detergente neutro de forragens: Comportamento ingestivo e cinética ruminal

“…Variações na FDNfe de forragens vêm sendo avaliadas sobre as atividades de alimentação, ruminação, ócio e mastigação (De Boever et al, 1993a;De Boever et al, 1993b;Mooney & Allen, 1997;Clark & Armentano, 1999;Soita et al, 2000;Schwab et al, 2002), sendo que em três desses estudos ocorreu efeito da FDNfe da forragem sobre a atividade de mastigação (De Boever et al, 1993b;Mooney & Allen, 1997;Soita et al, 2000) porém nos demais a atividade de mastigação não foi alterada (De Boever et al, 1993a;Clark & Armentano, 1999;Schawb et al, 2002). Em outro estudo houve correlação significativa entre o teor de FDNfe da ração com as atividades de ruminação e mastigação (soma dos tempos entre alimentação e ruminação) mas não com a atividade de alimentação (Beauchemin et al, 2003).…”