奶牛乳腺上皮细胞的不同培养方法比较及激素和细胞因子对β-酪蛋白mRNA表达的诱导

本试验旨在建立一种高效的奶牛乳腺上皮细胞培养方法,并研究不同激素和细胞因子对其表达β-酪蛋白mRNA的诱导作用.分别采用组织块培养法和机械破碎法培养奶牛乳腺上皮细胞,利用成纤维细胞和乳腺上皮细胞对胰酶的敏感性不同,对获得的细胞进行纯化.通过细胞计数法测定纯化细胞的生长曲线,通过免疫荧光组织化学染色法检测角蛋白18的表达,通过实时定量PCR法检测8种不同激素和细胞因子组合培养液诱导细胞表达β-酪蛋白mRNA的效果.结果表明:通过机械破碎法可以分离得到增殖旺盛的奶牛乳腺上皮细胞,与组织块培养法相比,具有细胞迁出速度快等优点.细胞生长曲线呈典型的“S”型.在纯化的乳腺上皮细胞及第20代乳腺上皮细胞中都检测到角蛋白18的表达.100 ng/mL类胰岛素生长因子Ⅰ(IGF-Ⅰ)显著提高了乳腺上皮细胞中β-酪蛋白mRNA的表达(P＜0.05).由结果可知,本试验采用的机械破碎法是一种高效的奶牛乳腺上皮细胞培养方法,100 ng/mL IGF-Ⅰ对细胞中β-酪蛋白mRNA表达的诱导效果最好.     

牛乳腺上皮细胞体外分离和培养

从健康奶牛乳房无菌采取乳腺组织,通过添加两种不同的培养液来分离、培养、纯化牛乳腺上皮细胞,研究乳腺上皮细胞的体外培养效果。结果表明,使用组织块接种可以得到大量细胞用于体外培养。在以DMEM/F12为基础的普通培养液中进行乳腺上皮细胞体外培养,原代细胞生长较慢,细胞形态不典型。而添加表皮生长因子、胰岛素、氢化可的松所组成的完全培养液中,奶牛乳腺上皮细胞生长良好。并通过细胞形态学观察,细胞染色体核型分析,荧光免疫细胞染色方法鉴定了培养的细胞表达上皮细胞特异的角蛋白K14,K15。结果表明,分离培养的细胞是牛乳腺上皮细胞。     

机械破碎法分离奶牛乳腺上皮细胞的体外培养研究

采用机械破碎法分离奶牛乳腺上皮细胞 ,并对分离细胞 (试验组 )和未分离的乳腺组织块 (对照组 )进行体外培养 ,研究乳腺上皮细胞体外培养的效果。培养液由DMEM /F1 2 加 2 0 %小牛血清组成 ,培养条件为 5 %CO2 、 37℃。机械破碎法分离的细胞在培养 2d开始生长增殖 ,7d基本长满培养板底部 ;而培养的乳腺组织块细胞到 5d后才呈现旺盛生长 ,长满培养板底部需 1 4～ 1 5d。结果表明 ,机械破碎法是分离乳腺上皮细胞的一种有效方法     

酶消化组织块法体外培养奶牛乳腺上皮细胞

建立稳定培养奶牛乳腺上皮细胞系的方法。结合酶消化法和组织块法,在体外进行分离培养奶牛乳腺上皮细胞,利用胰酶消化进行纯化和传代。通过倒置显微镜观察、细胞爬片姬姆萨染色和角蛋白18免疫组织化学方法对培养的细胞进行形态学观察和鉴定。观察发现,细胞排列紧密,呈多角形或梭形,长满后呈铺路石样。胞核呈圆形或椭圆形,核仁清晰可见,多为3~5个。通过细胞角蛋白18免疫组织化学方法对乳腺上皮细胞进行鉴定,呈阳性反应。获得的乳腺上皮细胞增殖旺盛,培养至40代生长活性仍然稳定。酶消化组织块法成功培养出奶牛乳腺上皮细胞,是分离乳腺上皮细胞的一种有效方法。     

TGF-β1对奶牛乳腺上皮细胞增殖与凋亡的影响

应用特异性方法检测转化生长因子(TGF-β1)对奶牛乳腺上皮细胞增殖和凋亡的作用,用不同浓度的TGF-β1作用于体外培养的奶牛乳腺上皮细胞,在不同时间收集培养细胞及其培养液,应用MTT法检测细胞增殖、应用分光度法检测caspase-3活性、测定DNA片段化率法检测细胞凋亡。结果表明,1、5、10ng/mL TGF-β1试验组与对照组比较细胞增殖差异显著(P<0.05),随TGF-β1浓度增大抑制细胞增殖作用增强。细胞凋亡检测显示,1、5、10ng/mL TGF-β1试验组与对照组比较细胞凋亡差异均显著(P<0.05),随TGF-β1浓度增大促进细胞凋亡作用增强。TGF-β1可以抑制奶牛乳腺上皮细胞的增殖,促进奶牛乳腺上皮细胞凋亡。     

胰岛素样生长因子-Ⅰ、肝细胞生长因子、转化生长因子-β1、干扰素-γ对奶牛乳腺上皮细胞增殖活性的影响

本试验应用组织块培养和差速消化法获取原代奶牛乳腺上皮细胞,免疫荧光鉴定正确后MTT法评价不同浓度的胰岛素样生长因子-Ⅰ（insulin-like growth factor-Ⅰ,IGF-Ⅰ）、肝细胞生长因子（hepatocyte growth factor, HGF）、转化生长因子-β1（transforming growth factor-β1,TGF-β1）、干扰素-γ （interferon-γ,IFN-γ）对奶牛乳腺上皮细胞体外增殖的影响。结果表明,IGF-Ⅰ、HGF分别在 10～200和0.1～100 ng/mL对乳腺上皮细胞的增殖呈正相关,而TGF-β1（2.5～100 ng/mL）、IFN-γ（5～160 ng/mL）则剂量依赖性地抑制乳腺上皮细胞增殖。提示,IGF-Ⅰ、HGF均能促进奶牛乳腺上皮细胞的体外增殖,该作用在一定浓度范围内有剂量依赖性;TGF-β1、IFN-γ对乳腺上皮细胞的增殖作用出现剂量抑制效应。     

原代奶牛子宫内膜上皮细胞体外培养方法的改进

目前利用奶牛子宫内膜上皮细胞体外培养技术，建立奶牛子宫内膜炎模型从而减少不可控因素来研究奶牛子宫内膜炎疾病已成为国内外普遍使用的一类方法，因此获得高纯度、同一性的子宫内膜上皮细胞是体外研究的关键环节，国内外所使用方法主要是酶消化法、组织块贴壁法和组织块消化贴壁法。本文旨对先前的方法进行改良，建立一种简便易行、培养周期短、细胞活性及形态良好的原代奶牛子宫内膜上皮细胞体外培养技术。采用健康未孕奶牛子宫为试验材料，取下子宫内膜组织，加入5 mL含2%双抗、40%胰酶的DMEM/F12培养基，4 ℃消化12 h，再将组织移至25 cm²细胞培养瓶中贴壁培养。获得原代细胞后，应用角蛋白-18抗体对细胞进行免疫组化荧光鉴定，并对第3代细胞采用CCK-8法测定不同时间点的D_{450 nm}值，绘制细胞生长曲线。结果显示，培养至第8天，原代细胞基本铺满细胞培养瓶瓶底，有效地缩短了常规组织块贴壁法的周期。通过角蛋白-18免疫组化荧光鉴定，原代上皮细胞的阳性率可达98%以上，相比常规组织块贴壁法来说，纯度明显提高，省去了细胞纯化的操作步骤。细胞增殖状态，符合正常的分裂生长特性。试验结果表明将常规组织块贴壁法进行了优化改良，不仅缩短了培养周期，同时提高纯度，保持细胞活性，为原代奶牛子宫内膜上皮细胞体外培养技术的改良提供一定的参考。     

山羊乳腺上皮细胞的分离、培养与超微结构观察

从山羊乳腺取部分组织进行细胞培养，并通过控时消化分离纯化山羊乳腺上皮细胞，建立了山羊乳腺上皮细胞系。结果表明：用含150U／mL Ⅰ型胶原酶和100U／mL透明质酸酶的混合液，37℃消化组织块4h，可得到大量的分散单细胞用于原代培养，该法是获得山羊乳腺组织单细胞的适宜方法；以含10％胎牛血清和双抗的RP-M11640或DEME／F12培养液为基础液，在培养液中添加氢化考的松、胰岛素样生长因子-Ⅰ(IGF-Ⅰ)、表皮生长因子(EGF)及胰岛素一转铁蛋白一硒钠(ITS)对山羊乳腺上皮细胞的生长具有较明显的促进作用。上皮细胞显微和超微结构显示：山羊乳腺上皮细胞在体外培养过程中可形成岛屿状单层聚集和类似圆顶状的结构；传代培养到第7代的细胞仍增殖旺盛，细胞内有丰富的脂滴和高尔基小泡，细胞分泌活动旺盛。     

奶牛乳腺上皮细胞和成纤维细胞的体外培养与鉴定

为体外培养纯化出稳定的奶牛乳腺上皮细胞和成纤维细胞,试验通过外科手术的方法取妊娠后期或泌乳期的荷斯坦奶牛乳腺组织,分离乳腺腺泡,用组织块法体外培养奶牛乳腺细胞,应用差时胰酶消化法和差速贴壁法将奶牛乳腺上皮细胞和成纤维细胞分别纯化出来,并用免疫组化的方法对细胞的纯度进行鉴定。结果表明:纯化的奶牛乳腺上皮细胞多为多角形,细胞核呈圆形或椭圆形,核仁清晰可见,多呈鹅卵石样或铺路石样生长,并可分泌乳滴,角蛋白-18反应阳性,波形蛋白反应阴性;纯化的奶牛乳腺成纤维细胞多为长梭形,呈旋涡状或放射状生长,角蛋白-18反应阴性,波形蛋白反应阳性;经纯化后2种细胞的纯度均可达95%以上,可满足后续试验的要求。     

胰岛素、催乳素和氢化可的松对奶牛乳腺上皮细胞增殖和凋亡的影响

本研究旨在探讨胰岛素(A)、催乳素(B)和氢化可的松(C)三种泌乳激素对奶牛乳腺上皮细胞增殖和凋亡的影响。将正常的荷斯坦奶牛乳腺上皮细胞进行体外培养,采用L9(34)正交试验设计,以无血清无激素培养基作为对照,研究了在培养液中添加不同浓度的三种泌乳激素组合对奶牛乳腺上皮细胞增殖和凋亡的影响。结果表明,泌乳激素的添加能够促进奶牛乳腺上皮细胞的增殖,48 h之前,A2B3C1组合最有利于奶牛乳腺上皮细胞的增殖,60 h之后最优组合为A3B2C1即50 ng/mL催乳素、500 ng/mL胰岛素和0.1 ng/mL氢化可的松,三种激素对试验结果影响的主次顺序为A>C>B;泌乳激素对奶牛乳腺上皮细胞凋亡的影响不大,但A1B2C2,即500 ng/mL催乳素、50 ng/mL胰岛素和0.1 ng/mL氢化可的松组能减少凋亡细胞数量。说明,在正常的奶牛乳腺中,泌乳激素主要是通过促进奶牛乳腺上皮细胞的增殖为进一步的泌乳和乳品质的提高奠定坚实的生理基础。     

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.     

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.     

Prevalence of gastric lesions in racing Alaskan sled dogs

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.     

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.     

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.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.