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1.
目前泌乳反刍动物尤其是奶牛乳腺营养研究已成为动物营养研究中的热点,乳腺血流量是影响乳腺营养物质吸收、摄取和利用的关键因素之一,因此乳腺血流量的准确测定也具有切实的理论和实践意义.本文以奶山羊乳腺为研究对象,利用transit-time超声血流量计对不同条件下乳腺血流量的检测及其准确性进行了评估.结果发现,结扎阴部外静脉...  相似文献   

2.
目的:研究荷斯坦奶牛乳腺发育中乳糖的变化规律.方法:高效液相色谱法测定荷斯坦奶牛乳腺发育中乳糖的含量.结果:围产期,乳腺中才出现可检测到的乳糖;泌乳期乳糖含量增高,泌乳140d达到峰值;退化期乳腺乳糖含量迅速降低,退化30d含量很少.结论:不同生理时期,荷斯坦奶牛乳腺中的乳糖含量不同.  相似文献   

3.
选取21头经产并确诊为乳房炎奶牛为乳房炎组,另选健康奶牛21头为对照组,分别于泌乳l,6,14,21,28,35和45d取材,每组每个时间点设3个重复,采集血液和乳腺组织。分光光度法测定各组活性氧(ROS)、一氧化氮(NO)、丙二醛(MDA)含量,研究氧自由基在奶牛乳房炎发病过程中的动态变化。结果表明:乳房炎奶牛血清及乳腺组织中ROS、NO和MDA显著高于对照组奶牛,提示乳房炎奶牛机体组织细胞和乳腺上皮细胞受到氧化损伤,过氧化物和自由基参与了乳房炎的发生过程。  相似文献   

4.
具有泌乳功能的乳腺上皮细胞系可作为乳腺发育学、乳腺病理学、泌乳生物工程学研究的细胞模型,本研究测定了激素对奶牛乳腺上皮细胞系泌乳功能的影响,为阐述泌乳机制提供工作基础。应用HPLC方法对体外培养奶牛乳腺上皮细胞的酪蛋白和乳糖的分泌情况和细胞培养液中的酪蛋白、乳糖含量进行测定,以确定胰岛素、催乳素和孕酮处理后的奶牛乳腺上皮细胞的泌乳功能。试验结果表明:奶牛乳腺上皮细胞具有酪蛋白和乳糖的分泌能力,在72h内,随着细胞培养时间延长,胰岛素处理组细胞中的酪蛋白和乳糖的升高趋势不明显,孕酮处理组升高趋势较明显,催乳素处理组升高趋势很明显;胰岛素处理组、催乳素处理组和孕酮处理组细胞培养液中酪蛋白升高趋势均很明显,乳糖含量均很高,三组激素比较而言,胰岛素处理组乳糖含量最高。此外,三组激素对乳腺上皮细胞活力影响均很大,在72h之内,总体变化为:催乳素处理组和孕酮处理组细胞活力均升高,胰岛素处理组细胞活力下降。  相似文献   

5.
不同中药对奶牛乳腺上皮细胞抗氧化能力的影响   总被引:1,自引:0,他引:1  
为研究中药对奶牛乳腺抗氧化能力的影响,选取7种中草药(王不留行、黄芪、漏芦、木通、通草、蒲公英、甲珠)测定其对体外培养的奶牛乳腺上皮细胞抗氧化能力的影响.测定了奶牛乳腺上皮细胞中的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性、丙二醛(MDA)质量分数、一氧化氮(NO)含量和一氧化氮合酶(NOS)活性.结果表明中药组奶牛乳腺上皮细胞SOD、GSH-Px和CAT活性高于或显著高于正常对照组(P>0.05,P<0.05,P<0.01),MDA、NO、NOS质量分数低于或显著低于正常对照组(P>0.05,P<0.05,P<0.01).中药能减少脂质过氧化产物MDA的生成,同时提高奶牛抗氧化酶活性,增强了奶牛的抗氧化能力.  相似文献   

6.
为了研究奶牛乳腺肥大细胞的数量与奶牛乳腺胶原纤维面积的相关性,试验对奶牛泌乳期和静止期乳腺进行采样,应用甲苯胺蓝组织化学染色法观察奶牛泌乳期和静止期乳腺肥大细胞数量的变化特点,应用苦味酸天狼猩红染色法观察奶牛泌乳期和静止期乳腺胶原纤维面积的变化特点。结果表明:静止期奶牛乳腺肥大细胞的数量明显比泌乳期多(P0.01),静止期奶牛乳腺胶原纤维的面积明显比泌乳期大(P0.01)。静止期奶牛乳腺肥大细胞的数量多,胶原纤维的面积也大;泌乳期的奶牛乳腺肥大细胞的数量少,胶原纤维的面积也小。说明奶牛乳腺肥大细胞的数量与胶原纤维的面积存在明显正相关性(r=0.677,P0.05)。  相似文献   

7.
奶牛乳腺上皮细胞体外培养研究进展   总被引:1,自引:0,他引:1  
体外培养的奶牛乳腺上皮细胞(BMECs)常被用于研究乳成分的合成调控以及乳腺的生理代谢。近年来,随着越来越多永生化奶牛乳腺上皮细胞系的建立,其应用也更为广泛。本文综述了奶牛乳腺细胞系的种类和奶牛乳腺细胞体外培养的方法,为研究乳腺上皮细胞的功能及泌乳机制提供参考。  相似文献   

8.
奶牛乳腺上皮细胞(BMEC)具有分泌乳汁的特殊功能,体外培养的奶牛乳腺细胞是研究乳成分合成调控和乳腺生理代谢的良好模型。近年来,奶牛乳腺体外培养模型受到越来越多的关注,其应用也更广泛。本文主要从奶牛乳腺体外培养模型在乳成分合成调控和乳腺生理代谢机制领域的应用两个方面进行简要综述。  相似文献   

9.
为了研究奶牛乳腺肥大细胞的组织化学特点和分布特征,对21头发育各期奶牛乳腺进行取样,应用免疫组织化学方法(SP),观察奶牛乳腺肥大细胞类胰蛋白酶的表达。结果显示,奶牛乳腺肥大细胞表达类胰蛋白酶,肥大细胞数量在各期有显著差异,泌乳期的乳腺肥大细胞数量明显减少(P〈0.01),分娩后60d奶牛乳腺肥大细胞的数量最少。结果表明,肥大细胞数量随生理周期的改变而改变,静止期奶牛的局部免疫能力增强。  相似文献   

10.
乳腺退化是奶牛干奶过程中的关键阶段。在乳腺退化过程中,乳腺上皮细胞内的囊泡和脂滴逐渐增多,细胞器萎缩,细胞紧密连接通透性增加,乳成分合成能力下降,细胞凋亡增加。近年来,越来越多的研究开始关注干奶期奶牛乳腺退化发生机理及其调控手段,主要原因是加速奶牛干奶初期乳腺退化一方面可以降低干奶期乳腺内感染发生的风险,另一方面有提高短干奶期(30 d左右)奶牛下一泌乳周期产奶量的潜在可能。目前研究表明,转化生长因子-β1(TGF-β1)/Smad和酪氨酸激酶(JAK)/信号传导与转录激活因子3(STAT3)2条信号通路在乳腺退化中扮演着重要角色,且通过营养手段可以调控奶牛的乳腺退化过程。本文旨在对奶牛乳腺退化的相关机制和乳腺退化营养调控最新研究进展进行综述,以期为现代高产奶牛健康养殖提供新的思路,为未来进一步研究奶牛乳腺退化提供参考。  相似文献   

11.
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。  相似文献   

12.
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.  相似文献   

13.
14.
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.  相似文献   

15.
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.  相似文献   

16.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
<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.  相似文献   

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