日粮酪氨酸水平对9～12周龄泰和乌骨鸡生产性能及组织黑色素含量的影响

试验旨在研究日粮酪氨酸水平对9～12周龄泰和乌骨鸡生产性能、游离酪氨酸含量和组织黑色素含量的影响。选用56日龄泰和乌骨鸡270只,随机分成6组,每组设3个重复,每个重复15只鸡,饲养至12周龄。6个处理组日粮酪氨酸水平分别为0.45%、0.65%、0.85%、1.05%、1.25%和1.45%。结果表明:泰和乌骨鸡平均日增重、料重比随着日粮酪氨酸水平的提高先增加后降低,在1.05%水平时的平均日增重最大,料重比最低且与0.45%水平组差异极显著(P0.01)。此外,酪氨酸水平极显著(P0.01)影响平均日采食量。泰和乌骨鸡血清及组织中游离酪氨酸含量随日粮酪氨酸水平的提高先增加后降低。心脏、肌肉、皮肤组织中游离酪氨酸的含量在1.25%水平时达到最高,且与0.45%水平组差异极显著(P0.01);而血清和肝脏组织中游离酪氨酸的含量在0.85%水平时达到最高。组织中黑色素含量随着日粮酪氨酸水平的提高先增加后降低。肝脏、肌肉、皮肤中黑色素的含量在1.05%水平时达到最高且与0.45%水平组差异极显著(P0.01);而心脏组织中黑色素的含量在1.25%水平达到最高。在一定的酪氨酸水平范围内,提高日粮酪氨酸水平可提高泰和乌骨鸡血清及组织中游离酪氨酸含量、组织中黑色素的含量和生产性能。     

日粮酪氨酸水平对泰和乌骨鸡生产性能及组织黑色素含量的影响

选用28日龄泰和乌骨鸡135只,随机分成3组,每组设5个重复,每个重复10只鸡(公母各半),饲养至12周龄.在5～8周龄3个处理组日粮酪氨酸水平分别为0.424%、0.566%和0.708%,在9～12周龄3个处理组日粮色氨酸水平分别为0.402%、0.521%和0.640%.结果表明:(1)在5～8周龄,泰和乌骨鸡平均日增重随日粮酪氨酸水平的提高显著降低(P<0.05),但酪氨酸水平对料重比和平均日采食量无显著影响(P>0.05);泰和乌骨鸡胸肌黑色素含量随日粮酪氨酸水平的提高极显著增大(P<0.01),但腿肌和皮肤黑色素含量未受酪氨酸水平影响(P>0.05).(2)在9～12周龄,日粮酪氨酸水平对泰和乌骨鸡平均日增重、料重比和平均日采食量均无显著影响(P>0.05),但显著影响胸肌和腿肌黑色素含量(P<0.05),而对皮肤黑色素含量无显著影响(P>0.05).在3个处理组中,高酪氨酸水平组的胸肌和腿肌黑色素最高.在本试验的酪氨酸水平范围内,提高日粮酪氨酸水平可促进泰和乌骨鸡组织黑色素沉积而不影响生产性能.     

日粮酪氨酸、苯丙氨酸、色氨酸水平和比例对泰和乌骨鸡生产性能及组织黑色素含量的影响

本试验旨在研究日粮酪氨酸、苯丙氨酸和色氨酸供给水平和比例对泰和乌骨鸡生产性能和组织黑色素含量的影响.选用612只1日龄泰和乌骨鸡,随机分成17个处理,每个处理设3个重复,每个重复12只鸡(公母各占1/2),饲养至4周龄.采用三因素二次回归正交组合设计试验方法,建立日粮三种氨基酸水平与泰和乌骨鸡日增重和组织黑色素含量的二次回归数学模型,得出0～4周龄泰和乌骨鸡分别取得最大日增重和组织黑色素含量时日粮三种氨基酸适宜供给量和比例模式.结果表明,日粮酪氨酸,苯丙氨酸和色氨酸供给水平和比例显著影响泰和乌骨鸡日增重和胸肌、腿肌黑色素含量(P<0.01),且泰和乌骨鸡取得最大日增重和组织黑色素含量时日粮三种氨基酸最适水平和比例模式各不相同.当日粮氨基酸含量分别为酪氨酸0.79%、苯丙氨酸1.06%和色氨酸0.13%,三者比例模式为Tyr:Phe:Trp=85:113:14(相对于日粮Lys含量的比值,Lys定为100)时,可取得最大日增重5.81 g/d;而当日粮三种氨基酸含量分别为酪氨酸0.81%、苯丙氨酸1.14%和色氨酸0.13%时,胸肌黑色素含量可取得最大值3.73%,三者最佳比例模式为Tyr:Phe:Trp=87:121:14.因此,通过调节日粮酪氨酸、苯丙氨酸和色氨酸供给水平和比例可改善泰和乌骨鸡生产性能以及体内黑色素的沉积.     

日粮酪氨酸水平对1～12周龄泰和乌骨鸡血清酪氨酸酶活性的影响

试验旨在研究日粮酪氨酸水平对1～12周龄泰和乌骨鸡体内酪氨酸酶活性的影响。选用1日龄泰和乌骨鸡270只,随机分成6组,每组设3个重复,每个重复15只鸡,饲养至12周龄。在1～4周龄6个处理组日粮酪氨酸水平分别为0.38%、0.58%、0.78%、0.98%、1.18%、1.38%,在5～8周龄6个处理组日粮酪氨酸水平分别为0.48%、0.68%、0.88%、1.08%、1.28%、1.48%,在9～12周龄6个处理组日粮酪氨酸水平分别为0.45%、0.65%、0.85%、1.05%、1.25%和1.45%。试验结果表明:在整个试验期血清中酪氨酸酶的活性均随着日粮酪氨酸水平的提高先提高后降低,且与不添加组(酪氨酸水平为1～4周0.38%、5～8周0.48%、9～12周0.45%)差异显著(P0.05或P0.01),在1～4周龄、5～8周龄和9～12周龄日粮酪氨酸适宜供给量分别为1.18%、0.88%和1.25%。在一定的酪氨酸水平范围内,提高日粮酪氨酸水平可提高泰和乌骨鸡体内酪氨酸酶活性。     

Dietary Copper Supplemental Level Affects Performance and Melanin Content in Tissues of Taihe Silky Fowls

本试验旨在研究饲粮铜添加水平对1 ～28日龄泰和乌骨鸡生产性能和组织黑色素含量的影响.选用1日龄泰和乌骨鸡270只,随机分成6组,每组设3个重复,每个重复15只鸡.试验鸡分别饲喂在基础饲粮(铜含量为4.75 mg/kg)中添加0、5、15、30、60、125 mg/kg铜的饲粮,饲养至28日龄.结果表明:饲粮铜不同添加水平对1 ～ 28日龄泰和乌骨鸡平均日增重、平均日采食量和料重比均无显著影响(P＞0.05),但适量添加可显著或极显著影响其血清、肝脏、肾脏、皮肤及肌肉的黑色素含量、酪氨酸酶活性(P＜0.05或P＜0.01),并呈现出随饲粮铜添加水平的提高先升后降的趋势.当饲粮铜添加水平为30 mg/kg时,泰和乌骨鸡血清和组织酪氨酸酶活性及黑色素含量达到峰值.由此可知,玉米-豆粕型基础饲粮中添加铜可提高泰和乌骨鸡组织黑色素含量,其适宜添加水平为30 mg/kg.     

饲粮铜添加水平对5～8周龄泰和乌骨鸡生产性能及组织黑色素含量的影响

本试验旨在研究饲粮铜添加水平对5～8周龄泰和乌骨鸡生产性能及组织黑色素含量的影响。选用29日龄泰和乌骨鸡270只,随机分成6组,每组3个重复,每个重复15只鸡。试验鸡饲喂在基础饲粮(铜含量为4.77 mg/kg)中分别添加0、5、15、30、60、125 mg/kg铜的饲粮,饲养至56日龄。结果表明:饲粮添加适量铜可显著影响5～8周龄泰和乌骨鸡平均日增重、平均日采食量和料重比(P<0.05),且在30 mg/kg时生产性能达到最佳。饲粮添加适量铜可显著或极显著影响血清、肝脏、肾脏、皮肤及肌肉的黑色素含量及酪氨酸酶活性(P<0.05或P<0.01),并呈现出随饲粮铜添加水平的提高先升后降的趋势。当饲粮铜添加水平为30 mg/kg时,血清和组织酪氨酸酶活性及组织黑色素含量达到峰值。由此可知,玉米-豆粕型基础饲粮中添加铜可提高生产性能和组织黑色素含量,其适宜添加水平为30 mg/kg。     

饲粮铜添加水平对泰和乌骨鸡生产性能和组织黑色素含量的影响

本试验旨在研究饲粮铜添加水平对 １～２８日龄泰和乌骨鸡生产性能和组织黑色素含量的影响。选用 １日龄泰和乌骨鸡 ２７０只,随机分成 ６组,每组设 ３个重复,每个重复 １５只鸡。试验鸡分别饲喂在基础饲粮（铜含量为 ４．７５ｍｇ／ｋｇ）中添加 ０、５、１５、３０、６０、１２５ｍｇ／ｋｇ铜的饲粮,饲养至 ２８日龄。结果表明：饲粮铜不同添加水平对 １～２８日龄泰和乌骨鸡平均日增重、平均日采食量和料重比均无显著影响（Ｐ＞０．０５）,但适量添加可显著或极显著影响其血清、肝脏、肾脏、皮肤及肌肉的黑色素含量、酪氨酸酶活性（Ｐ＜０．０５或 Ｐ＜０．０１）,并呈现出随饲粮铜添加水平的提高先升后降的趋势。当饲粮铜添加水平为 ３０ｍｇ／ｋｇ时,泰和乌骨鸡血清和组织酪氨酸酶活性及黑色素含量达到峰值。由此可知,玉米 －豆粕型基础饲粮中添加铜可提高泰和乌骨鸡组织黑色素含量,其适宜添加水平为 ３０ｍｇ／ｋｇ。     

日粮添加硒对5～8周龄泰和乌骨鸡生产性能及黑色素含量的影响

试验旨在研究日粮硒添加水平对5～8周龄泰和乌骨鸡生产性能及组织黑色素含量的影响。选用5周龄初始体重无显著差异(P>0.05)的乌骨鸡216只(公母各半),采用完全随机分组设计,随机分成6组,分别饲喂在基础日粮中添加0、0.10、.3、0.5、0.70、.9 mg/kg硒的试验日粮,每组设3个重复,每个重复12只鸡。试验期为4周。结果表明:日粮添加0.5 mg/kg硒显著降低泰和乌骨鸡料重比(P<0.05),显著提高日增重(P<0.05)。肝脏、肾脏、胸肌和皮肤黑色素含量随硒添加水平的提高呈先上升后下降的趋势。其中,当日粮硒添加水平为0.5 mg/kg时,肝脏和胸肌黑色素含量达到峰值,当日粮硒添加水平为0.3 mg/kg时,肾脏和皮肤黑色素含量达到峰值。玉米-豆粕型基础日粮中添加硒可改善5～8周龄泰和乌骨鸡生产性能和提高组织黑色素含量,且日粮硒适宜添加水平为0.3～0.5 mg/kg。     

日粮苯丙氨酸水平对0～4周龄泰和乌鸡生产性能及组织黑色素含量的影响

为研究日粮苯丙氨酸水平对泰和乌鸡生产性能和组织黑色素含量的影响。选用1日龄泰和乌鸡108只,随机分成3组,每组设3个重复,每个重复12只鸡(公母各半),饲养至4周龄。试验鸡组分别饲喂3种苯丙氨酸水平的日粮,日粮苯丙氨酸水平分别为0.73%、1.00%和1.27%。结果表明:日粮苯丙氨酸水平显著影响0~4周龄泰和乌鸡平均日增重(P<0.01),其中1.27%组日增重极显著高于0.73%组(P<0.01),显著高于1.00%组(P<0.05);1.00%组显著高于0.73%组(P<0.05)。但日粮苯丙氨酸水平对泰和乌鸡的饲料转化效率(料重比)和平均日采食量无显著影响(P>0.05)。胸肌黑色素含量随着日粮苯丙氨酸水平的提高而降低,1.27%组胸肌黑色素含量极显著低于0.73%和1.00%组(P<0.01),但0.73%和1.00%两组之间无显著差异(P>0.05)。尽管腿肌和皮肤黑色素含量在各组之间不存在显著差异(P>0.05),但黑色素含量有随日粮苯丙氨酸水平提高而增大的趋势。     

中草药添加剂对泰和乌骨鸡体内黑色素含量的影响研究

本试验根据乌骨鸡的生理特点,选用以何首乌、黑芝麻、血余炭等为主要成分的中草药,由人药乌发丸的配方加以改进,制成本试验用的3种复方中草药添加剂,探讨中草药添加荆对乌骨鸡体内黑色素含量的影响.选用1日龄的泰和乌骨鸡,分为对照组(基础日粮)、试验Ⅰ组(基础日粮+1%Ⅰ号中草药)、试验Ⅱ组(基础日粮+1%Ⅱ号中草药)和试验Ⅲ组(基础日粮+1%Ⅲ号中草药),共4组,每组设3个重复.每个重复15只鸡,共180只.分0-4周龄、5-8周龄、9-12周龄3个阶段,通过饲养试验、屠宰实验,研究各不同中草药添加剂对泰和鸟骨鸡体内黑色素含量的影响.结果显示:(1)4周龄时试验组各组织(胸肌、腿肌和皮肤)中黑色素舍量均比对照组高,但差异不显著(P>0.05);4周龄和12周龄时不同组织间黑色素舍量差异显著(P<0.05),但8周龄时不同组织间黑色素含量差异不显著(P>0.05).除8周龄试验Ⅱ组的皮肤及12周龄时试验Ⅱ组的腿肌黑色素含量略低于对照组外,其他试验组各组织中黑色素含量均高于对照组,但差异不显著(P>0.05).在各周龄不同中草药添加剂组间组织黑色素含量差异不显著(P>0.05),不同添加荆与不同组织问的互作效应也不显著(P>0.05).(2)胸肌黑色素含量在不同周龄间差异不显著(P>0.05),中草药添加剂组胸肌黑色素含量显著高于对照组(P<0.05),但不同添加剂组之间差异不显著(P>0.05).不同周龄间腿肌黑色素含量差异显著(P<0.05),其中12周龄黑色素含量显著低于4周和8周龄,各处理组间差异不显著(P>0.05).不同周龄间皮肤黑色素含量差异显著(P<0.05),其中12周龄黑色素含量显著低于4周龄,各处理组问差异不显著(P>0.05).所有组织黑色素含量随日龄的增大而运渐减少,且不同添加剂与不同周龄闻的互作效应不显著(P>0.05).     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

Mechanism of Action of Probiotic Function of Lactobacilli

乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.     

Evaluation of serum concentrations of biomarkers of skeletal metabolism and results of radiography as indicators of severity of osteochondrosis in foals

OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis.