共查询到18条相似文献，搜索用时 875 毫秒
1.
在以羊草和大针茅建群的山区草地上用食道瘘管样品，群落采摘样品，粪样和双样方样品对绵羊采食量和消化率测定和计算的结果表明，生长季内每只绵羊的日采食量为１５４５．１９～１６２５．１９克干物质，单位体重的日干物质采食量从第一期到最后一期表现为降低，放牧绵羊采食牧草的干物质，有机物质，粗蛋白质，粗纤维和无氮浸出物的消化率随生长的延长而下降，但牧草枯黄之前下降幅度不大。食道瘘管样的消化率比群落采摘样的消化率 相似文献
2.
放牧家畜的采食量是人们了解放牧系统动力学的关键之一。研究已查明，了解了放牧家畜的采食量和采食成分就能明晰家畜的营养状况，预测其生产性能，从而为草地管理决策提供目标，为优化资源利用提供基础数据。然而，估测放牧家畜的采食量及其组分是困难的，也是昂贵的。虽然那些改进的技术和方法有效地增强了人们获取家畜牧食行为数据的能力，但是测定放牧动物的采食量、采食成分和养分消化率一直以来都是营养学研究的挑战，方法众多，却各有利弊。因此，本研究针对目前估测放牧家畜采食量和采食成分的常用方法，如模拟采食法、牧前牧后差额法、酸不溶灰分法、三结合法、植物蜡层指示剂法和近红外光谱技术法，对它们的利弊和准确性进行讨论，并探析未来发展趋向，为今后的研究提供资料。 相似文献
3.
《动物营养学报》2020,(7)
采食是动物-植物相互作用的重要途径,是维持生态系统物质和能量循环的主要过程。动物的生产水平和草地的可持续性取决于动物的采食量,明确放牧家畜采食量是草地管理的关键之一。目前,直接观测法、指示剂法、粪氮指数法和近红外光谱法等现有技术被广泛运用到采食量的测定中。直接观测法利用较低成本对采食量进行计算,但主观性较强;食道瘘管法能够把握采食量却忽略了动物福利;近红外光谱法和饱和链烷烃法在测定采食量的同时能够认识家畜的择食特征。为此,本文对现有常规测定方法进行综述,分析影响测定放牧家畜采食量的主要因素,并提出放牧行为与无人机技术相结合等新思路,为今后草原精准化管理提供技术支撑。 相似文献
4.
以反刍时间为指标测定放牧家畜采食量方法的探讨 总被引：2，自引：0，他引：2
<正> 绪言作为测定放牧家畜采食量的一般方法可以列举出收割法,体重差法、不消化指示物质法等,此外,虽然还提出食道瘘管(Fistula)法和第一胃(rumen)瘘管法等可是测定值的精确程度和测定操作复杂程度等存在问题仍然是很多的。关于家畜的放牧活动,已经进行了许多研究,特别是了解到放牧时的采食行为,以及反刍行为,与采食量是有某些关系。然而,采食和反刍行为受着草地的植被,草的质量以及其他多种条件的影响,反刍行为与采食草之间存在的相互关系尚未进行过充分的探讨。 相似文献
5.
放牧生态系统家畜牧食行为研究进展 总被引：4，自引：0，他引：4
家畜牧食行为包括采食、反刍,游走,饮水,卧息和排泄粪尿,其中采食和反刍是两大主要行为。本文介绍了放牧家畜与牧草间的相互关系,放牧通过采食牧草,降低牧草光合叶面积指数而影响牧草生长发育。放牧作为一种人为干预,影响植被组成和群落结构,高放牧压力下,导致草地退化。在放牧情况下,牧草具有避牧和耐牧两种生存策略。由于放牧草地物种多样,家畜选择采食适口性高的植物或植物组成部分。介绍了国内外计算采食量的各种方法,包括计算放牧前后草地牧草生物量,通过内外源标记物计算排粪量或通过采食时间,单口采食率、单口采食量来计算采食量。家畜采食成分的测定一直以来都是难点,有直接观测法、瘤胃内容物或粪便镜检法、瘤胃瘘管法和炼烷烃技术等。 相似文献
6.
绵羊食道瘘管法和人工模拟法采集的草地牧草营养成分动态的比较研究 总被引：2，自引：0，他引：2
高山草原 7、8、10月和 1月放牧绵羊食道瘘管牧草样品和人工模拟采集牧草样品无论在粗蛋白质、粗纤维、粗灰分含量 ,还是干物质消化率方面 ,2种方法所采集牧草营养成分存在较大差异。具体表现为食道瘘管样品粗蛋白质和粗灰分含量高于人工模拟样品 ,二者最大差值分别为 6 .2 2 %和11.18% ,而粗纤维含量则低于人工模拟样品 ,最大差值为 4 .80 % ,2种方法采集牧草干物质消化率食道瘘管样也高于人工模拟样 ,二者最大差值为 7.74 %。试验表明 ,人工模拟法采集牧草样本尤其在本区黄草期 (10月 )不能真正代表放牧绵羊实际食入的牧草营养成分 ,但是在草地枯草期的 1月、二者的差值有减少的趋势。在本区放牧生态研究中牧草采样应以食道瘘管法为首选。 相似文献
7.
为了进一步探讨饱和链烷技术在典型草原自由放牧家畜中的应用,定量研究自由放牧绵羊食性及食量,于2004年6-9月在中国科学院内蒙古草原生态系统定位研究站放牧样地进行试验,选择体重及体况相近、健康无病的二岁羯羊(内蒙古细毛羊×蒙古羊)60只,按体重(36.9±2.6) kg聚类分组,设置6种放牧率(0,1.33,2.67,4.00,5.33和6.67羊/hm2)的轮牧实验,绵羊采食量的测定选择放牧率为1.33,4.00和6.67羊/hm2的处理,试验开始,每只羊投喂1粒QSM饱和链烷缓释胶囊。食性测定选用全部的放牧率进行,同时辅助全粪法、扣笼法一同评价。试验期内定期收集试验地牧草样品及绵羊粪便样品,使用气相色谱分析牧草和粪样中的链烷含量,应用链烷技术估测放牧绵羊的排粪量、牧草采食比例和干物质采食量。结果表明,植物链烷模式存在种间差异,运用链烷技术估测的排粪量和实际测得排粪量差异不显著(P>0.05),放牧绵羊主要采食7~9种牧草,且不同放牧季节不同放牧率绵羊采食的牧草种类和比例不同,但采食量差异不显著(P>0.05)。本研究表明,运用链烷技术结合扣笼方法可以估测天然草地自由放牧家畜牧草的采食比例、干物质采食量和排粪量。 相似文献
8.
9.
反刍动物采食量的概念与研究方法 总被引：26，自引：9，他引：17
本研究对反刍家畜采食量的研究发展与现状进行了回顾与总结,采食量及其相关术语的定义主要基于饲草料或家畜,其测定方法和精确含义有差异;反刍家畜采食是由生物和非生物因素相互作用共同影响的复杂动态过程,采食量影响因子主要分为家畜的(胃肠蠕动力、选择性采食等)、饲草料的(粗纤维含量、抗营养成分等)和饲养条件的(草层结构、草地饮水点分布等)因素3个方面;采食量的测定方法有基于牧草测定的直接法和基于家畜测定的间接法,后者较多地应用于放牧家畜;预测方法有基于数学函数和生物学原理的模型法,基于消化试验的经验法和结合家畜属性的改进经验法。舍饲条件下可准确地测定和预测家畜的采食量,但对放牧家畜还没有精确的方法。通过测定与饲草水平密切相关的家畜尿液、血液或粪便中的代谢物水平将成为预测放牧家畜采食量的准确方法。 相似文献
10.
高山草原绵羊放牧生态及消化代谢研究 Ⅳ采食量和消化代谢季节动态 总被引：8，自引：6，他引：2
利用放牧绵羊食道瘘管采集牧草样品,全收粪和羊粪液代替瘤胃液的二级离体消化法测得甘肃高山细毛羊成年羯羊在7、8、10和1月采食牧草干物质量依次为1115.91士158.52、1397.04士97.06、1314.69士145.40和715.55±116.32g/d.同时测定了绵羊有机物、粗蛋白质、消化能、代谢能、钙和磷采食量,并与NRC有关标准进行了比较,指出不同时期本区放牧绵羊CP和ME采食量的盈亏.随着放牧绵羊日采食量的减少,CP存留率和可消化CP利用系数则有大幅度提高. 相似文献
11.
L L Bennett A C Hammond M J Williams C C Chase W E Kunkle 《Journal of animal science》1999,77(8):2252-2258
Two methods of determining diet botanical composition, microhistological (MH), and stable carbon isotope ratio (CR) analyses were used to determine botanical composition of ingesta and fecal grab samples in steers grazing rhizoma peanut-mixed tropical grass pastures. Three pastures were used over two grazing seasons, 1992 and 1993, in Brooksville, FL. A weighted-disc double-sampling technique was used to determine forage mass and botanical composition, percentage of rhizoma peanut (Arachis glabrata), grass (Paspalum notatum and Cynodon dactlyon), and forb (primarily Chenopodium ambrosioides) on offer every 28 d throughout the grazing seasons. There was an effect of sampling date (P<.001), sampling date x pasture (P<.001), and sampling date x year (P<.001) on forage mass on offer. There was a pasture x year x sampling date interaction (P<.001) for all botanical components. In 1992 and 1993, using cannulated steers sampled every 56 d, there were interactions with year for rhizoma peanut and forb (P<.05), but not for grass with MH analysis (components: rhizoma peanut, grass, and forb). Ingesta and fecal rhizoma peanut (r = .73 and .92 for 1992 and 1993, respectively) and ingesta and fecal forb (r = .86 and .98 for 1992 and 1993, respectively) were positively correlated (P<.001). Ingesta and fecal grass were positively correlated (r = .52, P<.001), but the correlation was not as high. With the CR analysis (components: Calvin cycle [C3] plants and C4-dicarboxylic acid pathway [C4] plants), ingesta and corrected fecal (corrected for in vitro organic matter digestibility [IVOMD]) C3 plants were positively correlated (r = .62; P<.001). Diet composition of fecal grab samples from noncannulated steers, collected on the same sampling schedule as for hand-clipped pasture samples, differed at times due to the complexity of the sward (both rhizoma peanut and forb constituted a single component, C3, in the CR analysis). Based on these results, if there is a substantial contribution of forb to the diet, fecal microhistological analysis may be more informative than fecal carbon ratio analysis for estimating diet selection by cattle grazing tropical pastures. 相似文献
12.
《Strength and Conditioning Journal》2007,60(2):172-178
Grazing cattle and timber harvest are common practices associated with forested rangelands. Therefore, the objective was to document the effects of timber harvest and herbivory on nutritional quality and botanical composition of steer diets in grand fir (Abies grandis [Dougl. ex D. Don] Lindl.) and ponderosa pine (Pinus ponderosa P. & C. Lawson) forests. Three replicated grand fir sites were arranged as a split-plot design; timber harvest treatments—1) no harvest (CON), 2) thinning (TH), 3) clearcut (CL)—were whole plots, and herbivory treatments—1) large ungulate grazing (Graze), 2) wild ungulate grazing (CExc), and 3) exclusion of large ungulate grazing (TExc)—were the subplots. Three replicated ponderosa pine sites were arranged as a split-plot design; timber harvest treatments—1) CON and 2) TH—were whole plots, and herbivory treatments—1) GR, 2) BG, and 3) EX—were subplots. Diet samples were collected in June and August of 2001 and 2002. Crude protein, in vitro organic matter digestibility, acid detergent fiber, and neutral detergent fiber of the diets were only affected by season of use and were higher (P < 0.05) quality during the June grazing period. Botanical composition of diets was determined with the use of microhistological analysis of ruminal masticate. Within grand fir sites, graminoids were the major constituent in the diet (65%–91%), forbs intermediate (8%–31%), and shrubs least (0.2%–3.5%). Within ponderosa pine sites graminoids were the major constituent in the diet (83%–88%), forbs intermediate (10%–14%), and shrubs least (2%–3%). Season of use did not affect (P > 0.10) botanical composition in either grand fir or ponderosa pine sites. Timing of grazing had a greater influence on diet quality; however, previous herbivory and(or) timber harvest had a greater influence on composition of diets than did timing of grazing. 相似文献
13.
高山草原绵羊放牧生态及消化代谢系列研究Ⅲ。放牧绵羊食入牧草消化率动态及其限制性因素分析 总被引：3，自引：0，他引：3
采用羊粪液代替瘤胃液的牧草干物质二级离体消化率和绵羊食道瘗管方法研究高山草原放牧绵羊采食牧草干物质消化率季节动态,结果表明,在草地牧草生长的7月、8月、10月和1月,绵羊食入牧草(DM)消化率分别为61.00±1.96%,58.84±1.93%,51,40±0.84%和40.58±1.13%;同时应用灰色关联度分析方法对放牧绵羊食入牧草消化率限制因素综合分析认为:湿度、CP、NFE是影响消化率的主要因素。 相似文献
14.
Zewei Sun Daowei Zhou Luis M.M. Ferreira Qingzhen Zhong Yujie Lou 《Livestock Science》2008,116(1-3):146-155
The botanical composition, intake and digestibility of the diet selected by Inner Mongolian Cashmere goats grazing on a native Leymus chinensis plant community were measured in two grazing periods (June and August) using the n-alkane markers. In each grazing period, 48 Inner Mongolian Cashmere goats (24 wethers and 24 does with an average live weight of 22.1 ± 1.2 kg and 19.6 ± 0.8 kg, respectively) were divided in two groups (G1: grazing group; G2: cage-fed group) of 24 animals each. Based on the observation of G1 grazing behaviour, G2 goats were fed on herbage obtained by a simulative method and were housed in metabolism cages to determine the alkane faecal recoveries. Diet composition was estimated by comparing the odd-chain n-alkane pattern (C25–C35) of the selected plant species with the n-alkane faecal concentrations, corrected for their incomplete faecal recovery. The alkane pair C32:C33 and C36 alkane were used to estimate intake and diet digestibility, respectively. The results showed that the increase of herbage availability from June to August, resulted in higher (P < 0.05) DM, CP, ME, ADF and NDF intake of both wethers and does, with no evident changes in ADF and NDF intake in does., The intake of nutrients differed significantly between wethers and does in both experimental periods, except for NDF in EP1 and ME in EP2. Differences between grazing seasons and goats' sex in nutrients digestibility were not observed. Diet composition indicated seasonal differences, being Sonchus brachyotus, Artemisia frigida and Phragmites communis the main components of the diet in June. However, Suaeda corniculata, Chloris virgata, Xanthium sibiricum and Echinochloa crusgalli became the main diet components in August. Moreover, the sex affected significantly the diet choices in both grazing periods. 相似文献
15.
Abstract The long‐term effects of nitrogen, phosphate and lime on change in botanical composition and utilization under grazing of Southern Tall Grassveld of Natal are presented. Nitrogen, phosphate, lime and type of nitrogen affected botanical composition significantly. Generally, fertilization had the same effect on species composition score as heavy grazing. No change was observed in utilization by the grazing animal as nitrogen was increased, although a nitrogen X phosphate interaction was evident. Utilization by the grazing animal was not related to species composition score (SCS). Consequently, SCS alone cannot be used to predict grazing capacity. 相似文献
16.
J H Fourie E A N Engels Heila L H C DeBruyn 《African Journal of Range and Forage Science》2013,30(2):62-69
Abstract Four stocking rates (10, 7, 6 and 4 ha/large stock unit), in both rotational and continuous grazing, have been applied with cattle on Tarchonanthus veld. The crude protein content and digestibility of organic matter of handcut samples and herbage samples collected by means of oesophageal fistulated steers in the different treatments, were determined. The results indicated that the crude protein content (3,9 to 6,7%) and digestibility (48,7 to 59,4%) of handcut samples was not representative of the diet of grazing cattle. The crude protein content of the samples collected by means of oesophageal fistulated steers varied from an average of 13,6%. (October to December) to an average of 5,3% (July and August). On average, the digestibility of the fistula collected samples varied between 60,4% (February to April) and 50,2% (July to October). The crude protein content of the fistula collected samples tended to increase with increasing stocking rate while digestibility declined. Both crude protein content and digestibility of the fistula collected samples did not differ significantly between rotational and continuous grazing. 相似文献
17.
Four experiments were conducted to study factors affecting digestibility of forages in cattle, sheep, goats and white-tailed deer. In a series of digestion trials (Exp. 1), the dry matter digestibility of a moderately high fiber diet was greater in cattle than in deer. Digestibilities of the diet in sheep and goats were intermediate and not different from either extreme. In a second series of trials (Exp. 2), relative organic matter digestibilities were for goats more than sheep more than deer. However, in Exp. 2, intake in goats was very low and digestibility appeared to be positively related to retention time and inversely related to turnover rate. Results of three trials (Exp. 3) suggested that rate of digestion was related more to diet than to the animal species consuming the diet. In grazing animals (Exp. 4), goats digested a smaller percentage of consumed material than either cows or sheep during three of four seasons even though diets were of similar in vitro digestibility. This difference was related to a faster turnover and shorter retention time in goats. These data support the concept that there are species differences in gastrointestinal dynamics which may be which may be important determinants of adaptability to grazing conditions. 相似文献
18.
高山草原绵羊放牧生态及消化代谢的研究：Ⅰ放牧绵羊嗜食性研究 总被引：1，自引：1，他引：0
利用植物显微技术镜检法和食道瘘管法对放牧绵羊采食的高山草原植物成分与嗜食性指数进行分析。结果表明，绵羊在黄草期采食植物成分比青草期多，其嗜食性指数在不同时期变幅较大，随着冬季来临，绵羊对草地植物的嗜食性不如青草期强烈，至某些植物嗜食性是相对稳定的。 相似文献