早期断奶仔猪营养生理及其调控

在传统的养猪生产中，仔猪常在45-60日龄断奶。现在规模化养猪场多采用早期断奶技术，将断奶日龄缩短到21-28日龄。实行仔猪早期断奶可提高母猪的繁殖率和栏舍利用率，减少疾病由母体向仔猪的传播，并能提高生长期的生产性能和胴体品质。但早期断奶仔猪受心理、环境和营养应激的影响，常常发生所谓的“仔猪早期断奶综合征”，表现为食欲差、消化功能紊乱、腹泻、生长迟滞、饲料利用率低等。其中，营养应激是限制早期断奶仔猪生长性能的主要因素。一方面是因仔猪自身消化系统和免疫系统的不完善，另一方面则由于早期断奶对消化道组织和免疫系统的损害。因此应结合断奶仔猪营养生理特点，通过合理的营养调控手段，搞好日粮配制，以减轻生长抑制，减少腹泻，发挥仔猪早期断奶优势。     

谈高剂量氧化锌降低断奶后仔猪腹泻的作用机制

在现代养猪生产中，为发挥母猪最佳生产性能、减少仔猪疾病感染几率并提高仔猪生产性能，常采用早期隔离断奶（segregated early weaning，SEW）技术。早期断奶仔猪的消化系统尚未发育完善，难以承受由液体母乳向谷物性固体饲料变换带来的营养应激；仔猪与母畜骤然分离引起的心理应激；以及重新建群和等级地位确定过程中仔猪个体之间的争斗引起的环境应激（Spencer等，1989）。营养、     

仔猪断奶早期的营养调控

在现代化养猪生产中,各地已广泛采用早期断奶技术（21～30日龄）,但此时仔猪消化功能未发育完善,免疫机制不成熟,早期断奶是强烈的应激因素,极易造成仔猪早期断奶综合征。临床表现食欲差、消化不良、生长缓慢、抗病力下降、腹泻等,部分仔猪因此变成僵猪,甚至死亡。因此,对早期断奶仔猪进行营养调控,配制适宜饲粮是预防仔猪早期断奶综合症的重要措施。     

早期断奶仔猪腹泻与营养调控

仔猪早期断奶技术是国内外集约化养猪生产中普遍关注的先进技术,可提高母猪的繁殖率,减少由母体向仔猪的疾病传播,并能提高生长期的生长性能和胴体品质。在养猪发达的国家和地区,已开始推广应用14日龄超早期断奶技术。但早期断奶仔猪受心理、环境和营养应激的影响,常常发生“仔猪早期断奶综合征”,表现为食欲差、消化功能紊乱、腹泻、生长迟滞、饲料利用率低等,其引发因素主要是营养应激,因此通过营养调控手段,根据仔猪生长发育的生理特点,配制适合仔猪的饲料来减少仔猪腹泻,是一条行之有效的途径。1早期断奶仔猪的消化生理早期断奶仔猪消化…     

早期断奶仔猪配合饲料配制技术的探讨

现代养猪生产中 ,已基本普及仔猪早期断奶技术 ,而早期断奶仔猪由于受心理、环境、营养应激等因素影响 ,易导致仔猪断奶后的腹泻。Ｆｕｎｄｅｒｂｕｒｋｅ等[1] 曾研究了这三种应激对 2 8日龄断奶仔猪生理和生长的影响 ,结果发现断奶应激以营养应激影响最大 ,而心理和环境应激的影响则较小。故早期断奶仔猪料的配制 ,直接关系到断奶仔猪生长及今后生产性能的发挥。1　早期断奶仔猪腹泻原因分析1 1　仔猪饲料消化吸收不良　仔猪消化吸收不良与仔猪营养消化生理特点有很大的关系。仔猪乳糖酶的活性在出生后 2～ 3周时达到顶峰 ,然后很快下降…     

仔猪的消化生理与早期断奶

仔猪早期断奶是国内外集约化养猪生产中普遍关注的先进技术。它能提高母猪的繁殖率,减少疾病由母体向仔猪的传播,并能提高生长期的生产性能和胭体品质。目前国外养猪业发达国家已开始推广应用14日龄超早期断奶技术。但仔猪早期断奶时受心理、环境及营养应激影响,常表现为食欲差、消化功能紊乱、腹泻、生长迟滞、饲料利用率低等所谓“仔猪早期断奶综合症”。其引发因素主要是营养应激,即仔猪由原来吮食气味、味道、营养俱全的液态母乳转向采食香味差、坚硬、营养成分不同的干饲料。而此时仔猪消化系统尚未发育成熟,不能适应这种营养物质…     

早期断奶仔猪腹泻发生的原因及预防措施

仔猪早期断奶是将传统的仔猪8周龄以后断奶提早到3～5周龄的生产技术，此技术不仅可以提高母猪的生产力和圈舍的利用率，而且还可以降低母体向仔猪传播病原的机率，提高仔猪的生产性能和后期的酮体品质，但由于早期隔离断奶过程中的应激、饲料和营养的突然改变以及母猪自身免疫力低下等因素，可导致早期断奶仔猪消化机能紊乱，从而发生消化不良和腹泻，生长发育缓慢，严重的可造成死亡，给养殖业带来极大危害。     

仔猪早期补料的意义与常见问题

随着养猪业的迅速发展,仔猪早期断奶技术成为国内外集约化养猪中普遍关注的生产技术.仔猪早期断奶可以提高母猪的繁殖率,减少疾病由母体向仔猪的传播,并提高生长期的生长性能和胴体品质.但早期断奶仔猪受心理、环境和营养应激的影响,常常会出现腹泻等问题.因此通过营养调控手段,根据仔猪生长发育的生理特点,配合适合仔猪的饲料来给哺乳仔猪进行早期补料是一条行之有效的途径.     

早期断奶仔猪的营养调控

早期断奶仔猪的营养问题是猪的营养中的焦点问题。早期断奶仔猪的成活率和生产性能不仅与猪的品种、疾病防治、饲养管理相关，更重要的是猪的营养调控问题。解决了这个问题就可以解决早期断奶仔猪的断奶综合症，从而最终为养猪业谋求更高经济效益打下坚实的基础。1早期断?..     

早期断奶仔猪蛋白质营养需要研究

仔猪早期断奶已成为集约化、规模化养殖生产中所采取的一项重要手段，虽然早期断奶技术可以提高母猪生产性能，也有利于提高仔猪的成活率，但是伴之而来的腹泻、生长迟缓、消化不良、免疫力低下等仔猪“早期断奶综合症”严重影响了养猪业的经济效益，这一问题迄今还没有彻底解决。仔猪断奶综合症发生的原因包括很多方面，比如动物心理、环境以及营养等改变所产生的应激作用，经过多年的研究表明，营养性因素特别是饲粮蛋白质（CP）水平是引起仔猪早期断奶综合症的主要因素。本文从饲粮CP组成及水平对断奶仔猪腹泻及机体免疫的影响以及早期断奶仔猪CP需要量方面作一阐述，为养猪生产者提供一定的理论依据。     

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.