A comparative histological study of the number and size of the myenteric ganglia and neurones in the fore-stomach and abomasum of grey, white and black Karakul lambs.

Homozygous grey Karakul lambs are born with a lethal genetic factor responsible for death at weaning age. When put on a high roughage diet under field conditions they develop distended, thin-walled rumens and sand impacted abomasa. Homozygous white Karakul lambs have a similar factor but survive for a longer period. Black Karakul lambs are not affected. The present study was undertaken to compare by image analysis the number and size of the myenteric ganglia, and the number of myenteric neurones in the walls of the fore-stomach and abomasum of 24-h-old grey, white and black Karakul lambs. One square centimetre samples were taken from analogous areas of the rumen, reticulum, omasum and abomasum of 38 embalmed Karakul lambs. Haematoxylin and eosin stained histological sections of each sample were studied with a Vids 2 Image Analyzer. One way analysis of variance indicated a significant difference between the groups regarding the number and size of the myenteric ganglia and in the number of myenteric neurones in the reticulum, rumen and abomasum. The number and size of the ganglia and the number of neurones was greatest in the black lambs and decreased progressively in the white and grey lambs. The omasum was not affected. It is suggested that the paucity of myenteric ganglia and neurones in the regions examined is instrumental in causing the lethal condition described above.     

Scanning electron microscopy of the mucosal surface of the forestomachs and abomasa of grey, white and black Karakul lambs.

Homozygous grey and white Karakul lambs suffer from a lethal genetic factor causing death after weaning. Previous studies revealed large milk-filled rumens in the grey and white lambs which was attributed to a significant decrease in the number of myenteric ganglia and neurons in the rumen wall. This study was undertaken to determine the effect of milk on the epithelial lining of the forestomachs of affected grey and white lambs. In the forestomachs of the black lambs the polygonal epithelial cells were tightly packed, seemed to overlie one another and cytoplasmic projections occurred on the cell surfaces. In the grey and white lambs the epithelium had an eroded appearance due to sloughing of the surface cells and the cytoplasmic projections were lower and had a weathered appearance compared to the black lambs. No obvious differences could be detected in the abomasa of grey, white and black lambs. It is concluded that the milk in the forestomachs of the grey and white lambs is responsible for the epithelial changes.     

Histomorphometric study of the goat stomach during prenatal development

The aim of this study was to perform a morphometric analysis of the different structural tissue layers of the goat stomach to study their prenatal growth from mathematical models fitted to these morphometric data. A total of 90 embryos and fetuses were used, from the early stages of prenatal life until birth. The growth rate of the gastric wall was slower than that of body length; rumen was the stomach compartment displaying slowest growth. In the three non‐glandular compartments, the epithelial layer grew faster than the gastric wall itself, while the growth rate of the abomasal epithelium declined in the early stages of development. A decline in growth rate was also observed for the lamina propria and submucosa in rumen and reticulum from the early embryonic stages, whereas in omasum and abomasum these layers continued to grow as gestation progressed. The tunica muscularis displayed consistent growth in all compartments, growing faster than the gastric wall. Serosa thickness increased as gestation progressed, displaying a decline in growth‐rate only in the omasum. In conclusion, the dynamics of gastric wall growth were governed by the growth rate of each of the component tissue layers.     

断奶时间对不同日龄湖羊羔羊瘤胃形态及表皮生长相关基因表达的影响

本试验旨在探讨断奶时间对不同日龄湖羊羔羊瘤胃形态及表皮生长相关基因表达的影响。采用两因子试验设计,设断奶时间和羔羊日龄2个因子。选择初生重[(3.51±0.57)kg]接近的54只湖羊羔羊,28日龄时随机屠宰6只后按照同质性原则将剩余48只湖羊分为28日龄断奶组[(8.21±0.97)kg]和56日龄断奶组[(8.06±0.53)kg],分别在42、56、70和84日龄从2组中各随机挑选6只羔羊进行屠宰。采集瘤胃腹囊组织样品测定瘤胃乳头长度、宽度和肌层厚度,提取瘤胃组织总RNA测定表皮生长相关基因表达量。结果表明:28日龄断奶组羔羊瘤胃乳头长度和宽度显著高于56日龄断奶组羔羊(P0.05),瘤胃肌层厚度显著低于56日龄断奶组羔羊(P0.05)。断奶时间和羔羊日龄之间的交互作用对瘤胃乳头长度和肌层厚度有显著影响(P0.05)。28日龄断奶组羔羊瘤胃上皮胰岛素样生长因子结合蛋白(IGFBP)3、IGFBP5和IG FBP6表达量显著高于56日龄断奶组(P0.05)。羔羊瘤胃乳头长度与转化生长因子β(TGFβ)1和IGFBP6表达量呈显著负相关(r=-0.318,P=0.001;r=-0.520,P0.001);瘤胃乳头宽度与TGFβ1表达量呈显著负相关(r=-0.275,P=0.004),与IGFBP3和IGFBP5表达量呈显著正相关(r=0.344,P0.001;r=0.256,P=0.001)。综上所述,28日龄断奶促进湖羊羔羊瘤胃乳头发育和瘤胃表皮生长相关基因表达,可能参与羔羊瘤胃早期发育的调控。     

不同断奶日龄羔羊瘤胃组织显微及超微结构比较

试验通过比较不同断奶日龄的湖羊羔羊瘤胃组织结构的差异，特别是瘤胃乳头超微结构变化，旨在为羔羊适宜断奶日龄的确定提供瘤胃生长发育的依据。选择新生湖羊羔羊24只（初生重：2.80 kg±0.08 kg），随机分为3组，每组8只，分别为30日龄早期断奶组（EEW-30）、45日龄早期断奶组（EW-45）和60日龄常规断奶组（NW-60）。在各断奶日龄及75日龄时每组分别屠宰4只羔羊，测定体重及瘤胃空重，计算瘤胃相对重量；采集瘤胃组织进行显微及超微形态学测定。结果显示：①EEW-30组羔羊断奶体重极显著低于NW-60组（P<0.01），而EW-45组与NW-60组断奶体重无显著差异（P>0.05）；75日龄时3组羔羊的体重无显著差异（P>0.05）。各组羔羊瘤胃相对重量与其体重变化规律相同。②光镜下可见：断奶时，EEW-30组瘤胃壁厚度极显著低于NW-60组（P<0.01），EW-45组与NW-60组无显著差异（P>0.05）；75日龄时，EW-45组羔羊瘤胃壁厚度显著高于NW-60组（P<0.05）。断奶时EEW-30组瘤胃乳头较短小，极显著短于NW-60组（P<0.01），EW-45组也显著短于NW-60组（P<0.05）。断奶时瘤胃乳头宽度和面积在3组间差异均不显著，在75日龄时也无显著组间差异（P>0.05）。③扫描电镜观测结果显示：EEW-30组断奶时单位面积瘤胃微乳头（ruminal micro-papillae）数量极显著低于NW-60组（P<0.01），而EW-45与NW-60组间无显著差异（P>0.05）；75日龄时，3组羔羊单位面积瘤胃微乳头数量无显著差异（P>0.05）。上述试验结果显示，断奶时羔羊瘤胃形态结构在EEW-30与NW-60组间差异明显，而EW-45与NW-60组较为接近，瘤胃微乳头状结构也呈相同变化趋势。提示45日龄时断奶较为适宜。     

同一蛋白质水平不同赖氨酸与蛋氨酸比例对早期断奶藏羔羊复胃发育的影响

试验旨在研究18%蛋白质水平下,不同赖氨酸与蛋氨酸比例(Lys/Met)对早期断奶藏羔羊复胃发育的影响。选取(55±2)日龄断奶、体重(10.85±0.65)kg藏羔羊42只,随机分为3组,每组14只,公、母各半,分别饲喂18%蛋白质水平下不同Lys/Met比例的羔羊早期断奶料,试验期20 d。对早期断奶藏羔羊各胃室重量和组织形态指标进行了测定。结果表明,Lys/Met比例为3.1∶1时,藏羔羊复胃和瘤胃增重最好,瘤网胃乳头增长,瓣胃角化层、黏膜上皮和中央肌层增厚,皱胃胃底腺黏膜增厚效果最好。提示,早期断奶料营养水平影响藏羔羊复胃的生长发育,适宜的Lys/Met比例能够促进其良好的生长发育,在18%蛋白质水平下,藏羔羊早期断奶料Lys/Met比例为3.1∶1时效果最佳。     

开食料中性洗涤纤维水平对羔羊消化道组织形态和消化酶活性的影响

本试验旨在研究开食料中性洗涤纤维(NDF)水平对羔羊消化道组织形态和消化酶活性的影响。选择健康的初生湖羊公羔[(初生重(3.01±0.12)kg]18只,随机分为3组,每组6只羊。对照组随母羊哺乳,试验组随母羊哺乳同时于7日龄开始补饲NDF水平分别为15.13%(高NDF水平组)和10.00%(低NDF水平组)的开食料。35日龄时屠宰。结果表明:1)高NDF水平组的瘤胃乳头长度、肌层厚度,网胃乳头长度、乳头宽度、肌层厚度,瓣胃瓣叶宽度、肌层厚度以及皱胃肌层厚度均极显著高于对照组(P<0.01),瓣胃瓣叶长度、皱胃黏膜层厚度均显著高于对照组(P<0.05)。高NDF水平组的瘤胃乳头长度、网胃肌层厚度均极显著高于低NDF水平组(P<0.01),瓣胃瓣叶宽度、肌层厚度以及皱胃黏膜层厚度均显著高于低NDF水平组(P<0.05)。2)高、低NDF水平组的十二指肠隐窝深度极显著低于对照组(P<0.01),高、低NDF水平组的十二指肠肌层厚度极显著高于对照组(P<0.01)。高NDF水平组的空肠绒毛长度极显著高于对照组和低NDF水平组(P<0.01),高、低NDF水平组的空肠隐窝深极显著低于对照组(P<0.01),高NDF水平组的空肠肌层厚度显著高于对照组(P<0.05)。高、低NDF水平组的回肠绒毛长度极显著高于对照组(P<0.01),高、低NDF水平组的回肠肌层厚度极显著高于对照组(P<0.01)。3)对照组的瘤胃蛋白酶活性极显著高于高、低NDF水平组(P<0.01),高NDF水平组极显著高于低NDF水平组(P<0.01);低NDF水平组的瘤胃α-淀粉酶活性显著高于对照组(P<0.05)。低NDF水平组的空肠α-淀粉酶活性显著高于对照组和高NDF水平组(P<0.05),低NDF水平组的十二指肠、空肠和回肠胰蛋白酶活性显著高于对照组(P<0.05)。由此可见,15.13%NDF水平的开食料有利于断奶前羔羊消化道的发育。     

丁酸钠对断奶羔羊胃肠道发育的影响

本试验旨在研究丁酸钠对断奶羔羊胃肠道发育的影响。选取24只42日龄的断奶羔羊,随机分成4组,每组6个重复。空白对照组饲喂基础饲粮,抗生素组饲喂在基础饲粮中添加250 mg/kg黄霉素的饲粮,丁酸钠A组和丁酸钠B组分别饲喂在基础饲粮中添加2和3 g/kg包膜丁酸钠的饲粮。各组分别在试验第14天、第28天选取3只羔羊屠宰取样。结果表明:试验第14天时,各组断奶羔羊的瘤胃相对质量和相对容积以及各胃肠道形态指标均无显著差异(P>0.05);试验第28天时,与空白对照组相比,丁酸钠B组瘤胃背囊的肌层厚度,瘤胃腹囊的肌层厚度、乳头高度,十二指肠、空肠和回肠绒毛高度,空肠绒毛表面积以及空肠和回肠绒毛高度/隐窝深度显著增加(P<0.05)。由此可见,在饲粮中添加3 g/kg包膜丁酸钠并持续饲喂28 d可以促进断奶羔羊瘤胃乳头和肌层以及肠道绒毛的生长,增加肠道绒毛高度与隐窝深度的比值,有利于胃肠道的发育。     

Absorption of magnesium and other macrominerals in sheep infused with potassium in different parts of the digestive tract

Two metabolism trials were conducted with 12 crossbred wether lambs, each surgically equipped with a ruminal catheter and abomasal and ileal cannulae, to study the effect of K infusion in different sites of the digestive tract on site of absorption and flow of minerals. The treatments consisted of the infusion of 33.6, 12.0 or 12.0 g K/d as bicarbonate into either the rumen, abomasum or ileum, respectively. Each trial consisted of a minimum 5-d preliminary period, five 3-d collection periods to determine mineral balance and a 6-d sampling period to determine mineral flow and site of absorption. Chromic oxide was incorporated into the diet for use as a marker. Magnesium was absorbed primarily from the preintestinal region. Ruminal infusion of K tended to decrease preintestinal Mg absorption. Absorption of Mg in the entire tract was decreased (P less than .05) 43% when K was infused into the rumen. There was a slight absorption of Mg in the small intestine, followed by a net secretion into the large intestine. Serum Mg levels tended to be depressed in lambs infused with K intraruminally. Calcium flow from the preintestinal region was decreased (P less than .05) by infusion of K into the rumen. Only lambs infused with K in the rumen had a net secretion of Na into the small intestine. The large intestine was the primary site of net Na absorption for ruminal-infused lambs. Phosphorus flow from the preintestinal region was decreased (P less than .05) by infusion of K into the rumen. Potassium flow from both the preintestine and small intestine was increased (P less than .05) by ruminal K infusion. The infusion of K into the rumen, abomasum or ileum increased (P less than .05) the total absorption of K, with the small intestine being the major absorptive site. The infusion of potassium bicarbonate into the rumen of sheep raised (P less than .05) the pH of the ruminal contents 15%. Ruminal infusion of K depresses Mg absorption, while the infusion of K into the abomasum or ileum does not affect Mg absorption. Therefore, the role of K in grass tetany may be via this depression of Mg absorption.     

牦牛皱胃组织结构及黏膜免疫相关细胞研究

为揭示牦牛皱胃组织结构和黏膜免疫相关细胞的分布与数量变化的规律,采用组织化学法、图像分析法及透射电镜技术,对牦牛皱胃组织结构及上皮内淋巴细胞、浆细胞和肥大细胞变化进行了研究.结果表明:牦牛皱胃胃壁由黏膜层、黏膜下层、肌层和浆膜构成.皱胃幽门腺区胃小凹深度最深、腺体最长、肌层最厚;3个腺区肌层厚度、腺体长度之间差异极显著(P＜0.01);幽门腺区与胃底腺区、贲门腺区之间胃小凹差异极显著(P＜0.01),胃底腺区与贲门腺区之间差异不显著(P＞0.05).牦牛皱胃黏膜上皮内淋巴细胞数量和浆细胞数量,3个腺区之间差异不显著(P＞0.05);肥大细胞数量以胃底腺区最多,幽门腺区最少,两者之间差异极显著(P＜0.01),贲门腺区与胃底腺区和幽门腺区之间差异不显著(P＞0.05).皱胃各腺区固有层中均有大量的弥散淋巴细胞和孤立淋巴小结.电镜观察表明,胃小凹柱状上皮细胞排列紧密.幽门腺区固有层中有大量的黏液细胞,黏液细胞呈高柱状或锥体状,核位于基底部,在细胞顶端常聚集有较多的电子密度较高的颗粒.胃底腺区和贲门腺区有大量的壁细胞和主细胞.牦牛皱胃的组织结构和其他反刍动物基本相似,但各层有其明显特点.牦牛皱胃各腺区固有层中均有大量弥散淋巴细胞和孤立淋巴小结,使牦牛皱胃具有比其他反刍动物更强的黏膜免疫功能.     

舍饲和田羊与卡拉库尔羊生长发育指标的测定

本研究旨在对新疆南部地方品种绵羊平原型和田羊、山区型和田羊及卡拉库尔羊的17种生长发育指标进行检测分析,了解农区舍饲条件下新疆南部地方品种绵羊的基本生长发育情况。主要进行了2个品种、品系绵羊断奶后7个多月期间的17项生长指标的检测,通过SPSS 17.0统计软件分析其各项指标的差异显著性。结果表明：6月龄时,平原型和田羊与山区型和田羊间体高、尻长存在差异显著性(P<0.05),而后胸宽、尾长、尾宽、尾厚的差异极显著(P<0.01);山区型和田羊与卡拉库尔羊间前胸宽、后胸宽存在差异显著性(P<0.05);平原型和田羊与卡拉库尔羊间体重、胸围存在差异显著性(P<0.05),且前胸宽、后胸宽、尾长、尾宽、尾厚的差异极显著(P<0.01)。所检测各项指标的平均月增长量,平原型和田羊与山区型和田羊间体高存在差异显著性(P<0.05),而山区型和田羊与卡拉库尔羊间体高差异极显著(P<0.01);山区型和田羊与卡拉库尔羊管围存在差异显著性（P<0.05）;平原型和田羊与卡拉库尔羊间尾厚存在差异显著性(P<0.05)。对于绵羊体重、体长、体高、胸围等生长发育规律的研究结果表明,平原型和田羊的生长发育与山区型和田羊以及卡拉库尔羊相比较在这些方面具有优势。     

Study of the effect of presence or absence of protozoa on rumen fermentation and microbial protein contribution to the chyme

The aim of this study was to investigate the effect of presence or absence of protozoa on rumen fermentation and efficiency of microbial protein synthesis under different diets. Of 20 twin paired lambs, 1 lamb of each pair was isolated from the ewe within 24 h after birth and reared in a protozoa-free environment (n = 10), whereas their respective twin-siblings remained with the ewe (faunated, n = 10). When lambs reached 6 mo of age, 5 animals of each group were randomly allocated to 1 of 2 experimental diets consisting of either alfalfa hay as the sole diet, or 50:50 mixed with ground barley grain according to a 2 × 2 factorial arrangement of treatments. After 15 d of adaptation to the diet, the animals were euthanized and total rumen and abomasal contents were sampled to estimate rumen microbial synthesis using C(31) alkane as flow marker. Different ((15)N and purine bases) and a novel (recombinant DNA sequences) microbial markers, combined with several microbial reference extracts (rumen protozoa, liquid and solid associated bacteria) were evaluated. Absence of rumen protozoa modified the rumen fermentation pattern and decreased total tract OM and NDF digestibility in 2.0 and 5.1 percentage points, respectively. The effect of defaunation on microbial N flow was weak, however, and was dependent on the microbial marker and microbial reference extract considered. Faunated lambs fed with mixed diet showed the greatest rumen protozoal concentration and the least efficient microbial protein synthesis (29% less than the other treatments), whereas protozoa-free lambs fed with mixed diet presented the smallest ammonia concentration and 34% greater efficiency of N utilization than the other treatments. Although (15)N gave the most precise estimates of microbial synthesis, the use of recombinant DNA sequences represents an alternative that allows separate quantification of the bacteria and protozoa contributions. This marker showed that presence of protozoa decrease the bacterial-N flow through the abomasum by 33%, whereas the protozoa-N contribution to the microbial N flow increased from 1.9 to 14.1% when barley grain was added to the alfalfa hay. Absolute data related to intestinal flow must be treated with caution because the limitations of the sampling and maker system employed.     

小花棘豆对卡拉库尔羊瘤胃内环境的影响

试验将9只健康的卡拉库尔公羊分为3组,每组3只,分别为对照组、试验Ⅰ组和试验Ⅱ组,研究不同的小花棘豆添加量对卡拉库尔羊瘤胃内环境及微生物发酵参数的影响。结果表明,日粮中添加小花棘豆可降低卡拉库尔羊瘤胃液pH;随着小花棘豆添加量的增加,卡拉库尔羊瘤胃液氨氮含量升高,菌体蛋白含量下降;日粮中添加小花棘豆有促进瘤胃液总挥发性脂肪酸含量升高和乙酸/丙酸比降低的趋势。     

The effects of vagotomy on the abomasum in calves: radiography and protein gene product 9.5 immunohistochemistry.

Abomasal disorders of calves with total vagotomy, operated on at 1 week old, were investigated with radiography and protein gene product (PGP) 9.5 immunohistochemistry. Radiographic findings indicated abomasal atony with dilatation in all calves 2 weeks after vagotomy, while 4 weeks after vagotomy abomasal dilatation was detected in 2 calves and another 2 calves showed dilatation and impaction. The densities of PGP 9.5-immunoreactive nerves in the tunica muscularis decreased significantly in the corpus region of the greater curvature 2 weeks after vagotomy and in the pyloric region of the lesser curvature 4 weeks after vagotomy, and it was at its lowest 4 weeks after vagotomy in all regions examined. In conclusion, abomasal dilatation and/or impaction in vagotomized calves confirmed by radiography were related with a decreased frequency of nerves in the tunica muscularis of the abomasum.     

饲粮纤维水平对育肥羔羊瘤胃微生物组成及多样性的影响

试验旨在研究提高饲粮纤维水平对育肥羔羊瘤胃微生物组成及多样性的影响。试验选择健康无病、体重相近的2月龄杜湖杂交公羔,按照体重随机分为2组,每组38只,分别饲喂不同的饲粮,对照组（LW_CK）饲粮为精料+苜蓿,处理组（LW_EG）为精料+苜蓿+全株玉米青贮+花生秧;试验期150 d,其中预试期20 d,正试期130 d,试验结束后,每组随机选择5只羔羊屠宰取瘤胃内容物,通过16S rDNA高通量测序技术分析其微生物多样性及结构变化。结果表明,处理组羔羊瘤胃中细菌多样性显著高于对照组（P<0.05）。在门水平上,处理组羔羊瘤胃中优势菌门为拟杆菌门（Bacteroidetes）和厚壁菌门（Firmicutes）,对照组优势菌门为拟杆菌门和变形菌门（Proteobacteria）。提高纤维水平后显著增加了育肥羔羊瘤胃中厚壁菌门的相对丰度（P<0.05）;显著降低了变形菌门的相对丰度（P<0.05）。在属水平上,对照组与处理组羔羊瘤胃菌群共鉴定出195个属,处理组优势菌属为普雷沃氏菌属（Prevotella_1）和解琥珀酸菌属（Succiniclasticum）,对照组优势菌属为琥珀酸弧菌属（Succinivibrionaceae）和普雷沃氏菌属（Prevotella_7）。提高饲粮纤维水平,增加了育肥羔羊瘤胃中解琥珀酸弧菌属、密螺旋体属（Treponema_2）、疣微菌属（Ruminococcaceae）、月形单胞菌属（Selenomonas_1）的相对丰度,显著降低了琥珀酸弧菌属相对丰度（P<0.05）。综上所述,适量提高饲粮中纤维水平对育肥羔羊瘤胃微生物菌群结构有一定影响,能够促进部分纤维降解菌的增殖,有利于育肥羔羊的瘤胃发酵和养分消化利用。     

花椒精油对小尾寒羊生产性能和胃肠道组织结构的影响

【目的】本研究测定分析了不同剂量的花椒精油(EOZB)对小尾寒羊生产性能和胃肠道组织结构的影响,旨在为花椒精油在反刍动物方面的应用提供一定的理论参考。【方法】选取20只3月龄、活重接近的小尾寒羊随机分为4组,分别为对照组(CON)和试验Ⅰ、Ⅱ和Ⅲ组,对照组饲喂基础饲粮,试验Ⅰ、Ⅱ和Ⅲ组分别在基础饲粮中添加5(EOZB5)、10(EOZB10)和15 mL/kg(EOZB15)花椒精油;试验期52 d,试验结束后屠宰所有试验羊并采集10个部位(瘤胃、网胃、瓣胃、皱胃、十二指肠、空肠、回肠、盲肠、结肠和直肠)的胃肠道组织样,通过测定生产性能和胃肠道乳头长度、乳头宽度、黏膜下层厚度、肌层厚度、固有膜厚度、角质层厚度、绒毛长度、绒毛宽度和隐窝深度等指标系统性评价花椒精油对小尾寒羊胃肠道组织结构的影响。【结果】(1)花椒精油可以提高小尾寒羊生产性能。与对照组相比,EOZB10组平均日增重、干物质采食量和料重比显著增加,且显著高于其他两个试验组(P<0.05)。(2)花椒精油可以促进小尾寒羊复胃发育。与对照组相比,EOZB10组瘤胃黏膜下层厚度和肌层厚度显著增加(P<0.05),角质层...     

Rumen fermentation and histology in light lambs as affected by forage supply and lactation length

This study determined whether the rumen fermentation and histology traits may reflect the feeding strategy in light lambs (22-24 kg). Thirty-two single Rasa Aragonesa lambs were assigned to one of four treatments in a 2×2 factorial design. The factors were the inclusion of forage in the diet (alfalfa grazing vs. concentrate-fed indoors) and lactation length (weaning at 13 kg vs. suckling until slaughter). A multivariate canonical analysis discriminated individuals among feeding strategies. The main function differentiated weaned concentrate-fed lambs from the rest according to dorsal sac papillae height, ventral sac muscular layer thickness and the proportion of rumen valerate. The second function differentiated suckling concentrate-fed lambs from the rest according to plasma urea levels. Lactation length played an important role on rumen histology and protein utilization, especially in concentrate-fed lambs. Alfalfa grazing light lambs had similar rumen morphometric measures and fermentation characteristics, regardless of milk access.     

小麦饲料中添加木聚糖酶对高原型藏羊胃肠道发育的影响

旨在分析小麦粉中添加木聚糖酶(xylanase, Xyl)对藏羊羔羊胃肠道发育的影响。选择同质性良好的2～3月龄高原型藏羊公羔60只,随机分为两组,每组30只,各组内设置5个重复。对照组(Control group)饲喂不含木聚糖酶的日粮,试验组(Test group)饲喂含0.2%木聚糖酶的日粮,试验分为预饲期10 d和正试期90 d。饲养试验结束时,两组各随机选取5只羔羊进行屠宰,采集消化道组织置于多聚甲醛固定,并收集血液、瘤胃和空肠内容物。结果显示：1)与对照组相比,试验组瘤胃的角质层厚度、颗粒层厚度,瓣胃的乳头长度、乳头宽度、角质层厚度、颗粒层厚度,皱胃的黏膜厚度以及十二指肠的肌层厚度,空肠的绒毛高度、黏膜厚度,回肠的肌层厚度显著提高(P<0.05);2)对照组瘤胃和血清的LPS含量显著高于试验组(P<0.05);3)相较于对照组,试验组瘤胃的糜蛋白酶、胰蛋白酶、脂肪酶活性以及空肠的糜蛋白酶、α-淀粉酶活性显著提高(P<0.05);4)试验组瘤胃的总抗氧化能力水平、谷胱甘肽过氧化物酶及过氧化氢酶活性以及空肠的总抗氧化能力水平、谷胱甘肽过氧化物酶、超氧化物歧化酶...