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11.
Tropical Animal Health and Production - Serological studies have characterized the presence of the bovine viral diarrhea virus (BVDV) infection in water buffalo herds worldwide. However, the...  相似文献   
12.
Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25–30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration.  相似文献   
13.
When contagious bovine pleuropneumonia (CBPP) was first detected on a farm north of Melbourne, at Bundoora, in 1858, the predominant theory of miasma was being challenged by contagionist theories of disease transmission. This well‐documented case was recorded during a period of change in the scientific assessment of disease and therefore affords an exploration of what aspects of the landscape were considered important for livestock health at the time. Although the introduction, vaccination programs and eventual eradication of CBPP on mainland Australia has been well explored, scholars have neglected this aspect of the disease's history. By comparing 19th century records of farmland with how the site appears today, it is also possible to highlight the limited information provided by contemporary texts, while at the same time developing an appreciation of the ways in which the perception of the rural landscape has changed. This differing perception has implications for the utilisation of these sources for veterinary and environmental historians seeking to understand the mid‐19th century agricultural landscape and how it relates to animal health.  相似文献   
14.
The dual-purpose bovine system represents 98.4% of the bovine livestock of Veracruz, the main cattle-producing state of Mexico. This system supplies calves to meat companies, a sector in which Veracruz has been the national leader in the last decade. The objective of the present study was to analyze the effect of the altitudinal zonation of farms on livestock technology and productivity in a microbasin of the Gulf of Mexico where small farms predominate. Structured interviews were applied to producers located in three altitudinal zones (at average altitudes of 50, 140, and 450 m, respectively, for lower, middle, and upper zones). Sample size was 135 farms having similar land surface (within a range of 15–22 ha). The results indicated multiple differences among farms located in the three zones. Farms in the middle and lower zones presented higher productive indicators than those in the upper zone. Differences in herd structure and management resulted in important differences in productivity, income, and profits in milk and calf production. We concluded from this study that altitudinal zonation in Veracruz had a clear effect on the differentiation of small farms, which are representative of dual-purpose cattle. The upper zone performs cattle activity under conditions with greater disadvantages in the analyzed region.  相似文献   
15.
以浓硫酸为催化剂,采用甲醇-甘油复合溶剂,在高温高压的条件下对竹屑、杨木、桉木和松木进行液化,并且对液化产物进行了中和、过滤和旋转蒸发等一系列分级处理,并对液化固体残渣和气体产物进行分析。主要研究了以竹屑为原料的液化油的分级产物的组成及成分,研究结果表明:竹屑经甲醇-甘油液化,产物经过分级处理得到的主要产物为杂多酚、多糖苷和乙酰丙酸甲酯。多糖苷相主要含有多糖苷和未反应的甘油及其甘油聚合物,其中多糖苷主要为六元环吡喃糖苷,约占41.81%,甘油及其聚合物占47.27%;杂多酚相主要含有乙酰丙酸酯、杂多酚和甘油等化合物,其中甘油及其聚合物占38.04%,杂多酚相物质为难溶于水的焦油相的相对分子质量大的物质,约占杂多酚相的38.41%,并且杂多酚相的相对分子质量主要集中在990左右。  相似文献   
16.
Effects of dietary selenium (Se) on immune competence of yellowtail kingfish, Seriola lalandi, were investigated. The fish were fed one of the three experimental diets including a control diet without Se supplementation and two diets supplemented with Se from Se‐yeast (Selplex) at 2 and 4 mg/kg. After feeding for 6 wk, the fish were challenged by injecting Vibrio anguillarum and observed for 2 wk. Dietary Se had no effect on feed intake, feed conversion ratio, and survival over the course of 6‐wk feeding; however, it significantly increased weight gain and Se content in muscle. Following the bacterial infection, the immune‐stimulating effects of Se were observed in antibody, lysozyme, and bactericidal responses, and there was a corresponding increase in survival and hematocrit by Se. Under infectious condition, antioxidant capacity of fish as measured in terms of resistance of red blood cells to peroxidation and glutathione peroxidase activity also increased by supplementation of Se. Liver necrosis and kidney melano‐macrophages were only seen in surviving fish fed the control diet after the challenge. Furthermore, there was evidence of myopathy in fish fed the diet without Se supplementation. This study suggests that Se, supplemented at 2 or 4 mg/kg, can improve growth and health of yellowtail kingfish.  相似文献   
17.
In the dairy cow, negative energy balance affects milk yield and composition as well as animal health. Studying the effects of negative energy balance on dairy cow milk production is thus essential. Feed restriction (FR) experiments attempting to reproduce negative energy balance by reducing the quantity or quality of the diet were conducted in order to better describe the animal physiology changes. The study of FR is also of interest since with climate change issues, cows may be increasingly faced with periods of drought leading to a shortage of forages. The aim of this article is to review the effects of FR during lactation in dairy cows to obtain a better understanding of metabolism changes and how it affects mammary gland activity and milk production and composition. A total of 41 papers studying FR in lactating cows were used to investigate physiological changes induced by these protocols. FR protocols affect the entire animal metabolism as indicated by changes in blood metabolites such as a decrease in glucose concentration and an increase in non-esterified fatty acid or β-hydroxybutyrate concentrations; hormonal regulations such as a decrease in insulin and insulin-like growth factor I or an increase in growth hormone concentrations. These variations indicated a mobilization of body reserve in most studies. FR also affects mammary gland activity through changes in gene expression and could affect mammary cell turnover through cell apoptosis, cell proliferation, and exfoliation of mammary epithelial cells into milk. Because of modifications of the mammary gland and general metabolism, FR decreases milk production and can affect milk composition with decreased lactose and protein concentrations and increased fat concentration. These effects, however, can vary widely depending on the type of restriction, its duration and intensity, or the stage of lactation in which it takes place. Finally, to avoid yield loss and metabolic disorders, it is important to identify reliable biomarkers to monitor energy balance.  相似文献   
18.
旨在探究产蛋各期番鸭肝腺苷酸活化蛋白激酶(AMPK)信号通路基因表达和肝脂肪酸组成,为番鸭肝脂质代谢应答产蛋提供机理研究。本研究选取开产前22周龄、产蛋初期30周龄、产蛋中期40周龄和产蛋末期60周龄母番鸭各15羽,全自动生化仪测定血脂水平,苏木精-伊红(HE)染色和油红O染色观察肝组织学结构,实时荧光定量PCR (qRT-PCR)检测肝AMPK通路基因表达,气相色谱-质谱联用法(GC-MS)检测产蛋各期肝脂肪酸组成。结果表明,总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、甘油三酯(TG)和极低密度脂蛋白胆固醇(VLDL-C)水平在40周龄显著高于22、30和60周龄(P<0.05);高密度脂蛋白胆固醇(HDL-C)水平在30和40周龄显著低于22和60周龄(P<0.05)。肝HE和油红O染色切片显示,肝在22周龄呈实质状,至产蛋40和60周龄,肝脂滴沉积明显(P<0.05)。AMPKα1在22、30、40和60周龄呈本底低水平表达,并显著低于产蛋各期肉碱脂酰转移酶1(CPT1)和脂肪酸合成酶(FAS)的表达量(P<0.05),FAS在22、40和60周龄均呈高水平表达(P<0.05);羟甲基戊二酰辅酶A还原酶(HMGR)、肝细胞核因子4αHNF4α)、乙酰辅酶A羧化酶1(ACC1)和固醇调控元件结合蛋白-1(SREBP1c)在40周龄表达量显著高于22和30周龄(P<0.05)。肝中饱和脂肪酸(SFA)、单不饱和脂肪酸(MUFA)和多不饱和脂肪酸(PUFA)主要由C16∶0、C18∶0、C18∶1和C20∶2 n-6构成,分别占总脂肪酸含量的32%、16%、30%和9%。C14∶0和C16∶0含量在40周龄显著高于22周龄(P<0.05);C24∶0、C20∶2 n-6和PUFA含量在60周龄显著高于22和40周龄(P<0.05)。综上,番鸭产蛋期肝通过上调FAS等脂质合成基因表达,合成大量长链脂肪酸,沉积于肝,并增加血脂水平。  相似文献   
19.
A 4-mo-old northern red-shouldered macaw (Diopsittaca nobilis) was admitted to the veterinary hospital of the Arruda Câmara Zoo, in the State of Paraiba, Brazil, for investigation of an orbital mass. Given rapid progression and lack of response to treatment, the bird was euthanized, and an autopsy was performed. Histologically, the mass consisted of a retrobulbar invasive tumor characterized by tubular and rosette-like structures, with interspersed heteroplastic tissues, such as aggregates of neuroglial cells and islands of hyaline cartilage. The tumor was immunopositive for pancytokeratin, GFAP, NSE, and S100. These findings were compatible with an ocular teratoid medulloepithelioma, a neoplasm best described in humans but also reported rarely in young cockatiels and African Grey parrots.  相似文献   
20.
本试验旨在探明绵羊感染16型蓝舌病病毒(Bluetongue virus type 16,BTV16)后细胞因子IFN-γ、IL-2、IL-4和IL-10的消长特点。用实时荧光定量PCR检测方法对感染BTV16后3只绵羊上述4种因子mRNA进行检测,同时设立阴性对照绵羊,并以0 d mRNA为基准,计算mRNA的相对表达量,同时检测病毒抗体效价、测量绵羊体温。结果显示,接种BTV16的3只绵羊均不同程度产生抗体和体温症状,4种细胞因子的mRNA在接种病毒2~4 d内均出现显著上升,其中IFN-γ峰值在2.58~27.84倍之间,IL-2峰值在5.24~17.19倍之间,IL-4峰值在2.16~3.43倍之间,IL-10峰值在15.78~48.77倍之间,个体上升幅度存在显著差异,4种细胞因子均在高水平持续6 d左右后逐渐下降。对照绵羊上述参数在正常范围内波动。本研究阐明了接种BTV16后绵羊细胞因子IFN-γ、IL-2、IL-4、IL-10在转录水平上的消长特点,为进一步深入开展BTV感染特征、宿主机体免疫机制研究提供参考。  相似文献   
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