摘要
Chitosan was evaluated as a feed additive to mitigate in vivo CH4 emissions in beef cattle. Twenty-four crossbred heifers (BW = 318 ± 35 kg) were used in a randomized block design replicated in 2 periods. The design included a 2 × 3 factorial arrangement of treatments, which included diet (high concentrate [HC] or low concentrate [LC]) and 0.0, 0.5, or 1.0% of chitosan inclusion (DM basis). Diets were offered ad libitum and individual intake was recorded. An in vitro experiment to analyze chitosan's effect on fermentation parameters and gas production kinetics was performed. A diet effect (P < 0.01) was observed for CH4 emissions expressed as grams/day, grams/kilogram of BW0.75, and grams/kilogram of DMI. Heifers consuming the LC diet produced 130 g of CH4/d vs. 45 g of CH4/d in those consuming the HC diet. Incubation fluid pH increased linearly (P < 0.05) when chitosan was included in HC substrates. In vitro CH4 production was not affected (P > 0.10) by chitosan in HC substrate; however, when incubated with the LC substrate, CH4 production increased quadratically (P < 0.01) as chitosan inclusion increased. A digestibility marker × diet interaction occurred (P < 0.05) for DM, OM, CP, NDF, and ADF digestibility. Diet × chitosan interactions (P < 0.05) occurred for DM, OM, NDF, and ADF digestibility when Cr2O3 was used. When TiO2 was used, diet × chitosan interactions (P < 0.05) were observed for NDF and ADF. However, using indigestible NDF as an internal marker, DM and OM digestibility were improved (P < 0.05) by 21 and 19%, respectively, when chitosan was included in LC diets. In conclusion, feeding up to 1% of chitosan (DM basis) to heifers consuming a LC diet increased apparent total tract digestibility of nutrients. Enteric CH4 emissions were not affected by chitosan feeding, regardless of type of diet, and heifers consuming a 36% concentrate diet produced 2.6 times more methane per day than those consuming an 85% concentrate diet.
摘要译文
壳聚糖被评估为饲料添加剂以减轻肉牛的体内CH 4排放。24头杂交小母牛（体重\x3d 318±35公斤）被用于在2个时期重复的随机区组设计。该设计包括2×3因子排列治疗，其中包括饮食（高浓度[HC]或低浓度[LC]）和壳聚糖包合物（DM基准）0.0,0.5或1.0％。随意提供饮食并记录个体摄入量。进行体外实验以分析壳聚糖对发酵参数和气体产生动力学的影响。饮食效果（P 0。01）观察到的CH 4排放量表示为克/天，克/千克BW 0.75和克/千克DMI。食用LC食物的小母牛产生130克CH 4 / d对比消耗HC饮食者的45克CH 4 / d。当壳聚糖包含在HC底物中时，培养液pH线性增加（P 0.05）。体外CH 4产生不受影响（P 0。10）通过壳聚糖在HC底物中;然而，当与LC底物孵育时，随着壳聚糖包合物的增加，CH 4产量呈二次曲线增加（P 0.01）。消化率标记×饮食相互作用发生（P 0.05）DM，OM，CP，NDF和ADF消化率。 DM，OM，NDF处理×壳聚糖相互作用（P 0.05）和使用Cr 2 O 3时的ADF消化率。当使用TiO 2时，观察到饮食×壳聚糖相互作用（P 0.05）的NDF和ADF。但是，使用难消化的NDF作为内部标记，当壳聚糖包含在LC日粮中时，DM和OM的消化率分别提高了21％和19％（P 0.05）。结论是，向食用LC饮食的小母牛喂食高达1％的壳聚糖（DM基础）增加了营养素的表观总消化道消化率。肠内CH 4排放不受壳聚糖喂养的影响，不管饮食的类型如何，以及消耗36％浓缩饮食的小母牛每天产生2.6倍的甲烷比饮用85％浓缩饮食的小牛更多。
D. D. Henry;M. Ruiz-Moreno;F. M. Ciriaco;M. Kohmann;V. R. G. Mercadante;G. C. Lamb;N. DiLorenzo. Effects of chitosan on nutrient digestibility, methane emissions, and in vitro fermentation in beef cattle,[J]. Journal of Animal Science, 2015,93(7): 3539–3550