Oldham C L, Robinson T F, Hunter Z R, Taylor L, White J, Johnston N P
Department of Plant and Wildlife Sciences, Brigham, Young University, Provo, UT, USA.
J Anim Physiol Anim Nutr (Berl). 2014 Oct;98(5):908-13. doi: 10.1111/jpn.12157. Epub 2013 Dec 30.
The purpose of this study was to determine the diurnal composition and concentration of volatile fatty acids (VFA) and to determine VFA composition and concentration differences between stomach compartment 1 (C1) and caecum of alpacas fed grass and alfalfa hay. The study was divided into two experiments. In Experiment 1 (EXP 1), 10 male alpacas (3+ years old, 65 kg BW) were divided into two groups, housed in drylot pens, provided ad libitum water and fed alfalfa (AH) or grass hay (GH) for 30 days. The alpacas were slaughtered and the digestive tract collected, divided into sub-tract sections, weighed and digesta sampled for pH, dry matter (DM) and NDF. Volatile fatty acid composition and concentration were determined on C1 and caecal material. Four adult male (3+ years old, 60 kg BW), C1 fistulated alpacas were housed in metabolism crates and divided into two forage groups for Experiment 2 (EXP 2). Alpacas were fed the forages as in EXP 1. Diurnal C1 VFA samples were drawn at 1, 3, 6, 9, 12, 18 and 24 h post-feeding. There were no differences between forages for tract weight, C1 and caecum digesta DM or NDF. Differences were noted (p < 0.05) for pH between forages and sub-tract site. Volatile fatty acids concentrations were different (p < 0.05) for forage and site, and total VFA was higher for AH than GH (110.6 and 79.1 mm) and C1 than caecum (40.7 and 27.6 mm). Proportion of VFA was significant (p < 0.05) for forage and site, C1 acetate highest for GH (84.8 vs. 74.0 mm) and caecum acetate 83.7 and 76.2 mm for GH and AH respectively. These data demonstrate the level of VFA produced in C1 and the caecum of alpacas and the diurnal VFA patterns. Composition of VFA is similar to other ruminant species.
本研究的目的是确定挥发性脂肪酸（VFA）的日组成和浓度，并确定采食青草和苜蓿干草的羊驼胃第1室（C1）和盲肠之间VFA的组成和浓度差异。该研究分为两个实验。在实验1（EXP 1）中，将10只雄性羊驼（3岁以上，体重65千克）分为两组，饲养在干栏式畜舍中，自由饮水，并饲喂苜蓿（AH）或青草干草（GH）30天。宰杀羊驼并收集消化道，分成不同的节段，称重，并采集消化物样本测定pH值、干物质（DM）和中性洗涤纤维（NDF）。测定C1和盲肠内容物的挥发性脂肪酸组成和浓度。4只成年雄性（3岁以上，体重60千克）、安装了C1瘘管的羊驼被饲养在代谢笼中，并分为两个饲草组用于实验2（EXP 2）。羊驼如在实验1中那样饲喂饲草。在采食后1、3、6、9、12、18和24小时采集C1挥发性脂肪酸的日样本。不同饲草在消化道重量、C1和盲肠消化物干物质或中性洗涤纤维方面没有差异。在饲草和消化道节段部位之间观察到pH值存在差异（p < 0.05）。挥发性脂肪酸浓度在饲草和部位之间存在差异（p < 0.05），总挥发性脂肪酸含量苜蓿组高于青草组（分别为110.6和79.1毫摩尔），C1高于盲肠（分别为40.7和27.6毫摩尔）。挥发性脂肪酸的比例在饲草和部位之间具有显著差异（p < 0.05），青草组C1乙酸含量最高（84.8对74.0毫摩尔），盲肠乙酸含量在青草组和苜蓿组中分别为83.7和76.2毫摩尔。这些数据表明了羊驼C1和盲肠中产生的挥发性脂肪酸水平以及挥发性脂肪酸的日变化模式。挥发性脂肪酸的组成与其他反刍动物物种相似。
