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91.
92.
This study was conducted to evaluate the influence of back‐fat thickness (BF), at mating of sows, on the maternal and newborn circulating lipids, expression of placental fatty acids (FA) transporters and lipid accumulation in placenta. Full‐term placentas were obtained by vaginal delivery from BFI (9–14 mm; n = 37), BFII (15–19 mm; n = 43) and BFIII (20–27 mm; n = 38) sows according to BF at mating, and frozen placental sections were analysed for fat accumulation. Blood samples were collected from the sows of day 105 pregnancy and from cord blood at delivery. mRNA and protein expression levels were evaluated with real‐time RT‐PCR and Western blotting. Our results demonstrated that BFII females had significantly increased litter weight and placental efficiency, decreased maternal triglyceride (TG) and non‐esterified fatty acids (NEFA) levels, decreased maternal IL‐6, TNFα and leptin levels compared to BFIII females (< .05). BFIII sows were associated with significantly decreased newborn TG levels, increased newborn glucose, IL‐6 and TNFα levels compared to BFI or BFII sows (< .05). BFI and BFII females had significantly decreased placental TG, NEFA and cholesterol (CHOL) contents compared to BFIII females (< .05). Moreover, decreased CD36, FATP1, FABP4, and FABP1 mRNA and protein and FATP4 protein expression, and increased LPL activity were also observed in BFIII group compared with BFII group (< .05). PPARγ mRNA and protein and lipogenic genes such as SREBP‐1c, ACSL1, ACCα, FAS and SCD mRNA expression were downregulated or upregulated, respectively, in the placentas of BFIII sows compared to BFI or BFII sows (< .05). Overall, this study demonstrated that there is no advantage, in terms of litter live size, litter weight and placental FA transport and metabolism, in performing the mating of sows with BF>19 mm.  相似文献   
93.
The cryopreservation of testicular tissue is a potential method for preserving male fertility. However, the effect of cryopreservation on bovine calf testicular tissue is scarce. This study investigated the effect of different cryoprotectants on bovine calf testicular tissue at the molecular level. Testicular tissue from ten immature bovine calves (6 months) was collected after slaughter and cryopreserved in an extender containing different concentrations of the following five cryopreservation solutions (CP): bovine serum albumin (BSA) with 5% dimethyl sulfoxide (DMSO), trehalose with 5% DMSO, DMSO and glycerol and ethylene glycol (EG). After 7‐day cryopreservation, the expression levels of three spermatogonial stem cell (SSC)‐related genes, octamer‐4 (OCT4), KIT ligand (MGF/SCF) and kit oncogene (C‐KIT), were investigated by quantitative PCR (qPCR). The cell viability was highest for the tissues preserved with 30 mg/ml BSA (77.82% ± 1.22) and 40 mg/ml trehalose (74.23% ± 1.16) compared with other groups (p < 0.05), and the level of expression of the three genes was highest with 30 mg/ml BSA (p < 0.05). Compared with other CPs, the 30 mg/ml BSA and 40 mg/ml trehalose have the better cryopreserve protection. The 30 mg/ml BSA is the most viable media for the cryopreservation of testicular tissue from cattle.  相似文献   
94.
紫茎泽兰(Eupatorium adenophorum)在中国作为入侵物种,可造成食草动物中毒死亡,并给畜牧业带巨大的损失。为研究反刍动物采食紫茎泽兰后的中毒机理,本研究探讨了日粮中添加不同剂量的紫茎泽兰对萨能奶山羊(Saanen goat)血常规及肝、脾、肾的病理学影响。选择16只5~6月龄健康萨能奶山羊,随机分成对照组(日粮中未添加紫茎泽兰)和试验Ⅰ、Ⅱ、Ⅲ组(日粮配比中分别添加紫茎泽兰40%、60%和80%),每组4只。试验Ⅰ、Ⅱ、Ⅲ组分别饲喂含40%、60%和80%紫茎泽兰的混合日粮3个月,每两周检测一次血常规,试验末屠宰奶山羊,并观察其肝、肾、脾的病理学变化。结果表明,与对照组相比,各试验组血液中的白细胞(white blood cell,)和中性粒细胞(neutrophil,NEUT)均显著升高(P0.05),试验后期极显著高于对照组(P0.01);而各试验组血液中淋巴细胞(lymphocyte,LY)与血红蛋白(hemoglobin,HGB)均呈下降趋势,试验后期均极显著低于对照组(P0.01)。肝和脾肿大,肝组织出现淤血,肝细胞发生水泡变性及脂肪变性等,肾组织伴有出血、坏死、颗粒变性及水泡样变性的现象。因此,本研究结果说明紫茎泽兰对萨能奶山羊血液指标有显著影响,且长期摄入紫茎泽兰可引起动物肝、肾、脾等主要实质器官不同程度的损伤。  相似文献   
95.
为了解安徽省A型禽流感病毒感染情况,2018年4—5月,在安徽省北部、中部和南部7个市,随机选取各类型场点173个,在每个场点内随机采集35份咽喉/泄殖腔和环境拭子样品,使用荧光RT-PCR进行A型、H5亚型、H7亚型流感病毒核酸检测。结果显示:在4个养殖场、3个活禽批发市场和17个农贸市场检出了A型禽流感病毒,场点阳性率分别为2.9%(4/140)、75.0%(3/4)、80.9%(17/21),未检出H5和H7亚型流感病毒核酸;A型禽流感群体流行率为11.2%(95%CI:6.5%~15.8%),个体流行率为1.2%(95%CI:0.9%~1.5%);活禽交易市场内,禽群感染A型禽流感病毒的风险较高(OR=136,95%CI:32.7~549.4)。结果表明,A型禽流感病毒在养殖和交易环节存在一定的污染,而在活禽交易市场的污染更严重,是今后禽流感防控的重点,需继续加强活禽交易市场的管理和消毒灭源工作。  相似文献   
96.
犊牛魏氏梭菌的分离鉴定及致病性研究   总被引:1,自引:0,他引:1  
2017年1月,山东省某规模化奶牛场10~20日龄犊牛出现腹泻、拉血便、呼吸困难等症状,部分犊牛突然死亡。通过流行病学调查和尸体剖检,初步怀疑为魏氏梭菌感染。采集病料进行病理组织学检查、细菌分离鉴定、生化试验、16S及毒素基因检测等,证明疫情由A型魏氏梭菌所致。对死亡犊牛的肠内容物及分离菌株进行致病性研究,发现肠内容物及分离菌株具有较强的致病性。药敏试验结果显示,该菌对青霉素、头孢噻呋、恩诺沙星等表现极敏感。根据病原确诊情况及药敏试验结果,指导临床用药,及时控制了牛场疫情。  相似文献   
97.
为了解湖南省当前猪病的总体流行情况,对2017年湖南省13个市州72个规模化猪场和15个散养户送检的87例临床病例,进行了实验室诊断和流行病学分析。结果显示:该省猪群疫病多以散发形式出现,以高热、腹泻和呼吸道症状多见,气温偏低或偏高季节发病率较高,保育猪发病率高于其他生产阶段猪群,尤其是存栏量小的猪群;共检出11种病原,其中猪圆环病毒2型(PCV2)和高致病性猪繁殖与呼吸综合征病毒(HPPRRSV)检出率最高,且多以混合感染形式存在。结果表明,湖南省猪群中病毒感染较为广泛,PCV2和HPPRRSV是主要感染病原,在气温偏低和高温季节,要特别注意加强猪病防控。  相似文献   
98.
通过饲料混毒法测定鳢肠对棉铃虫生长发育的影响。结果表明,随饲料中鳢肠比例的加大和棉铃虫幼虫取食时间的延长,鳢肠对棉铃虫幼虫的生长发育具有明显的抑制作用。幼虫取食鳢肠比例高的饲料后,棉铃虫蛹质量显著降低,但羽化率和单雌日均产卵量与对照处理差异不显著;给棉铃虫幼虫饲喂鳢肠明显延长了幼虫和成虫历期,但对蛹历期的影响较小。  相似文献   
99.
‘Yandangxueli’ is a pear cultivar with predominant citric acid in the ripe fruit, different from most of pear cultivars such as ‘Gengtouqing’ in which malic acid is the predominant acid type. It was found that ‘Yandangxueli’ accumulated citric acid for three times against that in ‘Gengtouqing’ at fruit ripening stage. To investigate the mechanism of citric acid accumulation in ‘Yandangxueli’, organic acids content, gene expression and enzyme activity were studied in both cultivars. Five genes, Pp:mtCs, Pp:cyAco, Pp:cyIdh, Pp:mtMdh and Pp:cyMe which encoded citric synthase (CS), cytosolic aconitase (cyACO), NADP-dependent isocitrate dehydrogenase (NADP-IDH), NAD-dependent malate dehydrogenase (NAD-MDH) and NADP-dependent malic enzyme (NADP-ME) respectively, were identified from pear fruit. Their expression profiles and the corresponding enzyme activities were determined throughout fruit development in both cultivars. Results from these enzymes indicated that there were no strict relationship between gene expression, enzyme activity and citric acid accumulation. Expression analysis for two Py:vVAtp genes encoding vacuolar H+-ATPase A subunit and one Py:vVpp gene encoding Vacuolar H+-pyrophosphatase showed that they were all with up-regulated expression at the later development stage of ‘Yandangxueli’ but with down-regulated expression in ‘Gengtouqing’. Therefore, it is concluded that the different ability in citric acid transportation and storage might be involved in the high citric acid content in ‘Yandangxueli’.  相似文献   
100.
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