过瘤胃保护性亮氨酸稳定性研究

本研究以绵羊为供体动物,采用对pH值敏感的包被材料羧甲基纤维素钠对亮氨酸进行包埋处理,进行人工唾液消化试验、尼龙袋法与十二指肠液消化试验,检验该包被亮氨酸在瘤胃中的稳定性以及在十二指肠中的消化率.经人工唾液、瘤胃尼龙袋与十二指肠液消化试验.结果表明,包被亮氨酸样品在人工唾液和瘤胃液中较为稳定.亮氨酸在12 h的释放率分别为11.01%和34.10%;在十二指肠液中也具有较好的可消化性,亮氨酸在12 h的释放率为85.05%.     

过瘤胃保护性精氨酸稳定性检验研究

该研究以羧甲基纤维素钠和脂肪酸为壁材对精氨酸进行包埋处理,通过人工唾液消化试验、尼龙袋法与十二指肠液消化试验,对过瘤胃保护性精氨酸(RP-Arg)在绵羊消化道中的稳定性以及可消化性进行检验。试验结果表明,随培养时间的延长包被精氨酸的释放率呈升高趋势;经过16h的培养后,RP-Arg的释放率在人工唾液、瘤胃液和十二指肠液中分别为22.16%、31.47%和88.85%。结果显示,在人工唾液和瘤胃液中RP-Arg有较好的稳定性,在十二指肠液中RP-Arg具有较好的可消化性。     

瘤胃保护性蛋氨酸稳定性检验研究

根据氨基酸过瘤胃保护原理 ,将硬脂酸 (C1 8)、膨润土和蛋氨酸按一定比例制成包被蛋氨酸 ,通过体外法和半体内法检验该包被蛋氨酸在瘤胃中的稳定性以及在小肠中的消化率。试验结果表明 ,包被蛋氨酸在人工唾液、瘤胃液及真胃液中的溶解度分别为10 .2 1%、12 .2 1%和 18.68%。经人工唾液、瘤胃尼龙袋、真胃液和两级离体消化试验 ,结果表明 ,包被蛋氨酸样品在人工唾液和瘤胃液中较为稳定 ,蛋氨酸的释放率分别为 14 .73%和 2 2 .0 5 % ;在真胃液中也具有较好的可消化性 ,蛋氨酸的释放率为 90 .10 % ,两级离体消化试验中蛋氨酸释放率为 91.5 2 %。瘤胃尼龙袋法和真胃液体外法计算结果显示 ,样品中的蛋氨酸在试羊整个消化道内释放率为 89.0 3%。     

两种包被氨基酸过瘤胃保护效果和稳定性检验北大核心

试验旨在研究半胱氨酸和蛋氨酸包被产品的唾液、瘤胃和小肠降解率,检验过瘤胃半胱氨酸(RPCys)和蛋氨酸(RPMet)包被稳定性。采用人工唾液法、半体内尼龙袋法、体外模拟小肠消化法测定RPCys和RPMet降解率,综合评定RPCys与RPMet的过瘤胃保护效果。结果表明,RPCys与RPMet在人工唾液中2 h降解率分别为3.24%和9.32%,4 h降解率分别为4.10%和11.84%;在瘤胃中的有效降解率分别为8.97%和32.00%;在体外模拟小肠环境中2 h后降解率分别高于87.38%和81.12%。研究表明,RPCys和RPMet包被效果良好,在人工唾液和瘤胃中较稳定且有较高的小肠释放率;与RPMet相比,RPCys的过瘤胃保护效果较好。     

过瘤胃养分包被壁材人工唾液、瘤胃稳定性及小肠释放性能的研究

为探讨不同包被壁材在瘤胃中的稳定性及小肠释放性能,试验选用4只装有永久性瘤胃瘘管及十二指肠前端瘘管的健康崂山奶山羊去势公羊,分别测定中性羧甲基纤维素钠、单硬脂酸甘油酯、乙基纤维素、海藻酸钠、酸性羧甲基纤维素钠、乙酸纤维素、脂肪粉、聚乙二醇和血粉等9种包被壁材的人工唾液12 h消失率、瘤胃48 h降解率及小肠消失率。结果表明:脂肪粉不仅人工唾液及瘤胃降解率低,而且小肠消失率高,是最为理想的过瘤胃养分包被壁材;单硬脂酸甘油脂和血粉在人工唾液及瘤胃稳定性略差,用作包被壁材时应适当加大包被比例或增加包衣厚度;乙基纤维素和乙酸纤维素瘤胃降解率和小肠消失率均较低,包被时应注意包衣厚度,防止由于包被过度而影响养分释放与吸收。     

过瘤胃保护生物素的过瘤胃保护效果和稳定性评定

试验旨在应用体外模拟法研究过瘤胃保护生物素（RPB）的唾液、瘤胃和小肠降解率，为过瘤胃生物素产品的过瘤胃保护效果和稳定性提供理论参考。试验采用人工唾液法测定RPB的唾液稳定性，半体内尼龙袋法测定RPB在安装有永久性瘤胃瘘管的健康辽宁绒山羊瘤胃中的降解率，体外模拟小肠消化法测定小肠降解率，评定RPB的过瘤胃保护效果。结果表明：RPB在人工唾液中培养4 h内降解率低于18%，瘤胃中4、24 h内降解率分别为36.28%和59.34%，小肠中的平均降解率为84.85%。由此可见，RPB产品包被效果良好，在人工唾液和瘤胃中稳定性较好，且具有较高的小肠可消化性。     

熔融法制备包被纳米氧化锌工艺方法的研究

以纳米氧化锌与二氧化硅作为芯材,硬脂酸作为包被壁材,采用熔融分散-冷却法制备包被纳米氧化锌,以包被纳米氧化锌在人工胃液中的溶出率作为评价指标,得到最佳工艺条件:氧化锌、二氧化硅、硬脂酸的物料配比为50.3.3。在此工艺条件下,纳米氧化锌在人工胃液中3 h后的溶出率为1.87%,在人工肠液中6 h后的释放率为92.35%。该产品能够在仔猪的胃环境中保护纳米氧化锌,并且在仔猪的肠道环境中将纳米氧化锌释放出去,达到使纳米氧化锌发挥最大作用的目的。     

包衣壁材对赖氨酸保护效果的影响

为了评价包衣壁材对赖氨酸保护效果的影响,试验分别以壁材与赖氨酸之比为25∶75的包被比例,用前期筛选的乙基纤维素、乙酸纤维素、单硬脂酸甘油酯、血粉、脂肪粉等5种材料对L-赖氨酸硫酸盐进行物理包被,制得保护性赖氨酸制品,测定了保护性赖氨酸制品的人工唾液消失率、山羊瘤胃48小时降解率及小肠消失率。结果表明:脂肪粉是赖氨酸最好的包衣壁材,不仅人工唾液及瘤胃稳定性好,而且在真胃及小肠中易于释放和吸收;乙基纤维素也可对赖氨酸进行有效保护,但小肠消失率较低,包被时应注意包衣厚度,防止由于包被过度而影响小肠释放与吸收。     

肠溶性微生物微胶囊对断奶仔猪生产性能的影响

试验研究有益微生物微胶囊的肠溶性对断奶仔猪生产性能的影响。将有益微生物包被成微胶囊后分别置于人工胃液和人工肠液中进行肠溶性测定，结果表明，该胶囊在人工胃液中1h基本不崩解，在人工肠液中15min能释放活菌数超过90％。将该微胶囊、未包被的微生物和土霉素分别添加于饲料中，进行108头35日龄断奶仔猪40d的饲养试验，结果表明，与未包被的微生物组和土霉素组相比，微胶囊组日增质量显著提高，料肉比显著降低，且添加微胶囊组仔猪腹泻率为0。结论为该微胶囊可耐受胃液破坏，肠溶性好并可提高仔猪的生产性能，减少腹泻的发生。     

硫酸小檗碱微球体外释药性研究

为预测硫酸小檗碱微球的体内释放效应,以及制备更加符合机体生理特点的微球制剂,以硫酸小檗碱为模型药物,制备了壳聚糖-海藻酸钠载药微球。以生理盐水、人工肠液和人工胃液为释放介质,采用转篮法测定了载药微球在1 h～48 h的药物累计释放度。结果表明,在释放试验的1 h～12 h,人工肠液中的药物释放速度较快,在12 h药物累计释放率达到57.18%,而在生理盐水和人工胃液中的药物释放速度较慢,累计释放率分别为23.07%和11.04%,至48 h,在人工胃液、生理盐水和人工肠液中的药物累计释放率分别达到24.99%、51.29%和91.01%。在人工胃液中符合Higuchi方程,在人工肠液和生理盐水中的释放行为符合一级拟合方程,表明硫酸小檗碱壳聚糖-海藻酸钠微球具有良好的缓释性能。     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

Changes in proportion of canine urinary calculi composed of calcium oxalate or struvite in specimens analyzed from 1981 through 2001

The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.     

Smart Phone Assisted City-scale Wireless Sensor Network Deployment for Transportation System Monitoring

<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.