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81.
In ruminants, the ruminal epithelium not only has the function of absorbing nutrients but also is an important tissue to prevent harmful substances in the rumen from entering the blood circulation. Thus, the normal function of ruminal epithelium is critical for ruminants. However, subacute ruminal acidosis induced by high-concentrate diets often damages the barrier function of ruminal epithelium in ruminants. Recently, many studies have shown that dietary supplementation with thiamine is an effective method to alleviate subacute ruminal acidosis. In order to provide theoretical reference for the in-depth study of subacute ruminal acidosis and the application of thiamine in the future, this review introduces the effects of subacute ruminal acidosis on morphological structure, inflammatory response, and tight junction of ruminal epithelium. In addition, this paper summarizes the role of thiamine in maintaining ruminal epithelial function of ruminants during subacute ruminal acidosis challenge. 相似文献
82.
Yang Zi Chi Ma Huimin Li Suting Shen Yingchun Liu Ming Li Feng Gao 《Animal Science Journal》2021,92(1):e13613
This study investigated the effects of intrauterine growth restriction during late pregnancy on the ovine fetal renal function and renal antioxidant capacity. Eighteen ewes pregnant were randomly divided into control group (CG, ad libitum, 0.67 MJ ME·BW−0.75·day−1, n = 6), restricted group 1 (RG1, 0.18 MJ ME·BW−0.75·day−1, n = 6), and restricted group 2 (RG2, 0.33 MJ ME·BW−0.75·day−1, n = 6). At 140 days, the fetal blood, allantoic fluid and kidney tissue were collected to determinate fetal renal function and renal antioxidant capacity. The results showed that the fetal weight, kidney weight, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), aquaporin-2 (AQP-2) and aquaporin-3 (AQP-3), and total antioxidant capacity (T-AOC) in RG1 group were decreased compared with the CG (P < 0.05), but the contents of β2-Microglobulin (β 2-MG), cystatin C (Cys-C), filtered sodium excretion fraction (FENa), malondialdehyde (MDA), and hydroxyl radical (OH) in RG1 group were increased (P < 0.05). The impaired ovine fetal renal growth, antioxidant imbalance and dysfunction of glomerulus ultrafiltration, and the renal tubules reabsorption were induced by maternal malnutrition during late pregnancy. 相似文献
83.
Małgorzata Maśko Olga Witkowska-Piłaszewicz Tomasz Jasiński Małgorzata Domino 《Reproduction in domestic animals》2021,56(10):1315-1328
Infrared thermography is a non-invasive technique which allows to distinguish between pregnant and non-pregnant animals. Detecting accurate body surface temperatures can be challenging due to external factors altering thermograph measurements. This study aimed to determine the associations between the ambient temperature, the hair coat features and the temperatures of mares' abdomens. It compared pregnant and non-pregnant mares throughout 11 months. The research was carried out on 40 Konik Polski mares, which were divided into pregnant and non-pregnant groups. The temperature (Tmax, maximal; Taver, average; Tmin, minimal) of the mares' abdomen was evaluated in two regions of interest: the whole area of the lateral surface of the mares' abdomen (Px1) and the flank area of the lateral surface of mares' abdomen (Px2). During the increasing period, the slopes in the linear regression equation did not differ significantly for ambient (Tamb) and surface temperatures in both groups. In the decreasing period, the slopes did not differ significantly for Tamb and Tmax in the non-pregnant group. They also did not differ for Tamb and Taver in Px1 and Tamb and Tmin in Px1 in both pregnant and non-pregnant groups respectively. Other slopes varied significantly (p < .001). There was no evidence of parallel changes in hair coat features and measured temperatures. The flank area appears more suitable for thermal imaging in pregnant mares due to the seasonal fluctuations in hair coat lengths. 相似文献
84.
餐厨废弃物(food waste,FW)的资源利用受到广泛关注。FW焚化、填埋、堆肥、厌氧消化等技术因其面临的环境可持续性问题而受到越来越多的批评。饲料化技术可以将FW转化为高价值的饲料,从而减少固体废物的排放、养殖成本和环境污染,但该技术应符合减少、再利用和回收有机废物的处理原则。作者综述了FW的饲料化技术及其在动物生产中的应用。FW饲料化技术主要包括热处理、酶处理、藻类培养、昆虫过腹、发酵技术。其中热处理可以确保微生物安全性,是其他技术的预处理技术。藻类培养和昆虫过腹技术可以将FW转化为植物和昆虫蛋白,避免同源污染,但尚不清楚藻类和昆虫在FW利用过程中是否会造成污染物积累。酶处理和发酵技术可以将FW中大分子转化为小分子。酶的催化性能和稳定性容易受外界条件的影响,需要考虑特殊的酶制剂。发酵技术的机械化程度和资源利用率高,其核心是微生物,需要筛选有效的、能充分利用FW的微生物。目前FW在畜牧业中的应用较少,在其生产和应用中要特别注意用量和使用时间。为了使FW饲料真正作为动物饲料进入食物链,研究人员必须对不同动物(含不同生长阶段)的生长性能和产品特性进行研究,以确保动物健康及动物产品对人类健康没有负面影响。 相似文献
85.
Min Zhang Dan Zheng Zhimei Peng Yuting Zhu Rongrong Li Qiong Wu Yan Li Hongyi Li Weihua Xu Mao Zhang Qichun Hung Yanfa Sun 《The Journal of Poultry Science》2021,58(2):131
In this study, signaling pathways and key differentially expressed genes (DEGs) involved in lipid metabolism in muscle and fat tissues were investigated. Muscle and abdominal fat tissues were obtained from 35-day-old female broilers for RNA sequencing. DEGs between muscle and fat tissues were identified. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of DEGs were performed. A total of 6130 DEGs were identified to be significantly enriched in 365 GO terms, most of which were involved in biological processes, cellular components, and molecular functions in muscle and fat tissues. Three important lipid signaling pathways (pyruvate metabolism, the insulin signaling pathway, and the adipocytokine signaling pathway) were identified among the fat and muscle tissues of broilers. The key common DEGs in these pathways included phosphoenolpyruvate carboxykinase 2 (PCK2), acetyl-CoA carboxylase 1 alpha and beta (ACACA and ACACB), and the mitogen-activated protein kinase (AMPK) gene family. Hence, our findings revealed the pathways and key genes and gene families involved in the regulation of fat deposition in the muscle and fat tissues of broilers. 相似文献
86.
随着黑龙江省自然保护区数量及占地面积的迅速增长,自然保护区质量提升滞后以及建设与管理过程中诸多矛盾冲突的不和谐现状也随之显现,解决这些问题的关键在于推进自然保护区和谐发展.自然保护区的和谐是和谐社会内容的一部分,有关这方面的研究有利于促进我国社会主义和谐社会目标的最终实现.但目前我国关于构建和谐自然保护区的相关研究还处于初级阶段.本文在研究国内外自然保护区建设和管理相关理论的基础上,从法律保障体系建设、社区共管体系建设、生态补偿机制建设和区域发展援助基金成立,以及生态旅游开展等方面,提出了黑龙江省构建和谐自然保护区管理建议,为黑龙江省的生态文明和和谐社会建设提供了参考. 相似文献
87.
为建立一种快速、敏感、特异的口蹄疫病毒(Foot-and-mouth disease virus,FMDV)分型鉴别诊断实时荧光RT-PCR(Fluorescence quantitative,FQ-PCR)检测方法,根据O、A、AsiaⅠ三种血清型FMDV保守基因序列,设计能够检测到FMDV的特异性通用检测引物和A型检测引物,以及不同荧光素标记的MGB探针。通过对PCR反应体系和反应条件的优化筛选,建立了FMDV通用型和A型二重实时荧光RT-PCR检测方法,并对该方法进行了特异性、敏感性、重复性试验;利用所建立的方法,对123份疑似FMDV感染的临床样品进行了检测。结果显示,建立的FMDV通用型、A型二重实时荧光RT-PCR检测方法在10~1~10~7拷贝/μL模板范围内有很好的线性关系;对pGEM-T/FMDV-T和pGEM-T/FMDV-A重组质粒出现阳性扩增信号,但对正常细胞培养物对照和其他7种病原对照未扩增出特异性曲线;自123份疑似FMDV感染样品中,检出10份FMDV-T阳性,6份FMDV-T/FMDV-A双阳性并且与基因测序结果一致。结果表明,本研究建立的FMDV通用型、A型二重实时荧光RT-PCR检测方法重复性好、敏感性高、特异性强,最低检测模板浓度为10拷贝/μL,可用于FMDV的快速分型检测,为FMDV的早期检测及临床诊断提供了新方法。 相似文献
88.
为建立一种简便、快速、特异的猪伪狂犬病毒(PRV)gB抗原检测方法,利用单克隆抗体技术和侧向层析(LFA)技术,采用柠檬酸三钠还原法,制备颗粒大小为31.5 nm胶体金,再用胶体金标记纯化的抗PRV gB单克隆抗体10D4,在硝酸纤维素膜的质控带和检测带处,分别包被羊抗鼠IgG二抗和单克隆抗体6E9,组装成LFA方法通用胶体金层析试纸条。经测试,该试纸条最低能检测出1:640倍稀释的,TCID_(50)为1×10~(8.6)/0.1 mL的灭活PRV抗原,并与古典猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、猪圆环病毒2型(PCV2)、猪细小病毒(PPV)、猪流行性腹泻病毒(PEDV)均无交叉反应,特异性良好;室温干燥密闭的条件下,该试纸条至少可保存10个月。结果表明,本研究建立的试纸条方法操作简单、快速、敏感、特异,易于判定,适合基层PRV的大面积普查和现场检测。 相似文献
89.
90.