母牛的发情周期以及发情的鉴定方法

本文结合实际工作经验,从母牛发情周期和发情鉴定两个方面分析了母牛的繁殖技术,希望通过研究对广大同行有所帮助。     

妊娠树鼩生活习性的初步研究

为了探索妊娠阶段树Qu的生活习性，为其提供适宜的生活环境以保证胎儿在其体内能够正常发育，在2－8月份间对19只哺乳期间（含一只多次）的树Qu的生活习性进行初步研究，结果表明树Qu的妊娠天数大多为41－45d，妊娠的第二周树Qu的体重稍有下降，以后逐周呈明显的增加趋势，采食量也增加，但到分娩前食欲下降。     

鉴定猪饲料好坏的简便方法

目前,饲料行业竞争激烈,各厂家打起了价格战,小厂家更是互相降价,致使产品质量得不到保证。为迎合养殖户心理需要,添加了一些添加剂,导致出现许多问题,需广大养殖户引起注意。     

母羊的发情周期与发情鉴定

1发情周期发情周期,即母羊从上次发情开始到下次发情的间隔时间。在发情期内,未经配种或虽经配种而未受孕的母羊,其生殖器官和机体发生一系列周期性变化,会再次发情,绵羊发情周期平均为16天（14～21天）,山羊平均为21天（18～24天）。     

母牛发情的鉴定方法

母牛的发情呈周期性,正常情况下,母牛的发情周期平均为21天.母牛在发情周期的不同阶段会表现出不同的症状,根据母牛的发情症状可以判断出最适宜的配种输精时间,对于提高人工授精的成功率非常重要.目前,生产中常用的母牛发情鉴定方法主要有外部观察法、公牛试情法、阴道检查法和直肠检查法,现进行简单介绍.     

阴道涂片法鉴定犬发情周期的临床应用

对母犬阴道细胞学进行研究的目的,是为了对犬的繁殖管理进行更好的研究和控制[1,2]。阴道上皮的变化是由于生殖激素,特别是雌激素的作用引起的,这种变化可以在阴道涂片上的细胞中表现出来。因此,阴道涂片的检查可以帮助人们对母犬发情周期进行确定以及对生殖系统的异常进行诊断     

滇西树鼩源沙门氏菌的分离鉴定及生物学特性研究

【目的】确定试验滇西树鼩患病致死的原因,分析分离菌株的致病性与耐药情况。【方法】本研究按常规平板划线法对发病死亡的滇西树鼩心脏血、肝脏、脾脏、肺脏和肾脏进行病原菌分离,进一步对分离菌进行形态学观察、生化试验及16S rRNA基因鉴定,并进行药敏试验和致病性试验。【结果】从发病死亡的滇西树鼩肝脏和肺脏组织分离得到1株细菌。分离菌在麦康凯培养基上呈浅橘黄色单菌落,镜检为革兰氏阴性短杆菌。生化试验结果显示,分离菌能分解葡萄糖,不发酵乳糖,产气,产硫化氢等,符合沙门氏菌生化特性。遗传进化分析显示,分离株与肉用仔鸡源沙门氏菌CP082916菌株亲缘关系最近,16S rRNA基因核苷酸相似性为99%。药敏试验结果显示,分离菌对氯霉素、庆大霉素、新霉素、诺氟沙星等药物敏感;对克林霉素、万古霉素不敏感。致病性试验结果显示,该菌对树鼩及成年小鼠具有较强致病性,对小鼠的半数致死量(LD₅₀)为1.6×10⁶ CFU。病理组织学观察显示,感染组树鼩和小鼠肺脏肺泡间隔增宽、间隔内可见炎性细胞浸润;肝脏细胞排列紊乱,见大量坏死细胞崩解,窦状隙变形或减小,中央静脉淤血,...     

肉眼诊断鱼病的简便方法

为防治鱼病,需要对鱼病进行辨别。在没有专门仪器的情况下,可用肉眼作简单地诊断。其方法是:一看体表病鱼身体两侧肌肉、鳍基部特别是臀鳍基部充血,但充血情况不同,鱼病也有区别,如剥开皮肤,肌肉呈不同程度的点状充血,甚至全身肌肉呈深红色,为出血病;体表局部发炎充血,鳞片脱落     

树Qu的实验室繁殖

树Qu是一种在医学和生物学上用途广泛的实验动物遗传资源，但目前在国内树Qu的人工繁殖还没有大规模开展，本文主要就树Qu的实验室繁殖，妊娠，生产，哺乳，断奶五个方面进行了摸索，探讨，为树Qu的大规模繁殖提供了一些经验。     

一种准确简便的东方白鹤性别分子鉴定方法

东方白鹤为国家Ⅰ级重点保护动物，在自然条件下繁殖率很低，进行迁地保护及再引入措施对遗传多样性保护具有举足轻重的作用，成功地进行性别鉴定是其笼养人工繁殖的前提。本研究对4只东方白鹤，运用CHD基因的一对引物2550F／27181K进行了准确简便的性别鉴定，并对其序列结合其他5种远缘鸟类相应序列进行分析，证实了此种方法的科学性和可信度，分析了性别鉴定机理。这种安全、方便、准确的性别分子鉴定方法将有助于东方白鹤迁地保护及再引入措施的实施。通过分析可以看出，此种方法未来存在着广阔的应用前景。     

树鼩实验室繁殖的新方法

在实验室笼养条件下将28只健康成年树鼬按1:2或1:3的雄雌比例配对饲养,并每隔3周进行一次检查,通过一年的试验饲养,研究结果表明,这批实验树鼬共受孕45次,分娩37窝,流产2窝,死产3窝,总产仔147只,成活139只,另有3只母树鼦怀孕待产.每只母树鼩产仔2～3窝,每窝2～5仔,幼仔初生体重为(10.4±1.2)g,40日龄断奶体重为(66.2±15.7)g.该方法树鼩繁殖率和成活率极高,成本相对较低且操作简单,是一种值得参考和借鉴的新方法.     

野生瑶山亚种树鼩实验室驯养繁殖研究

[目的]对野生瑶山亚种树鼩进行实验室饲养驯化,繁殖培育瑶山亚种树鼩实验动物化种群。[方法]将野生瑶山亚种树鼩饲养在温度、湿度等条件可控的实验室中,引进初期以果蔬为主要饲粮,后期逐步过渡到以日常饲料为主,经过1个月左右使其适应实验室饲养环境;挑选符合种源要求的瑶山亚种树鼩,按公母比例为1∶1进行配种合笼,以体重增加以及腹部触诊判断母树鼩是否怀孕,对繁殖期母树鼩及仔树鼩进行特殊饲养管理。[结果]野生瑶山亚种树鼩经过1个月左右的饲养驯化,成活率达到96%,平均增重达到50g左右;母树鼩配种受孕率为24.53%,产仔12胎,产仔数42只,每胎平均产仔3.5只,出生存活率为92.86%,离乳存活率为42.86%。[结论]实现了对野生瑶山亚种树鼩的实验室饲养驯化,瑶山亚种树鼩的实验室繁殖工作虽已取得一定突破,但仍需进一步解决实验室饲养条件下母树鼩配种怀孕率低和仔树鼩存活率低等问题。     

Suppression of hepatitis B virus replication in Tupaia hepatocytes by tumor necrosis factor alpha of Tupaia belangeri

Recently, Tupaia belangeri was used to study the full replication cycle of hepatitis B virus (HBV) in the primary hepatocyte cultures. Thus, the Tupaia model represents a suitable model to study the effects of cytokines on HBV infection. Here, Tupaia tumor necrosis factor-alpha (TNF-α) was molecularly cloned and expressed in mammalian cells. A test system for the biological activity of Tupaia TNF-α was established on the basis of its cytotoxic effect to the murine fibrosarcoma cell line L929. Recombinant Tupaia TNF-α was able to suppress HBV replication in primary Tupaia hepatocytes (PTH). However, the formation of HBV covalently closed circular DNA (cccDNA) and viral RNA was not completely prevented. Therefore, Tupaia TNF-α may contribute significantly to the control of HBV infection though it is not able to completely inhibit HBV replication alone. The characterization of this important cytokine allows further studies on its antiviral actions in the Tupaia model.     

Relationships between body weight,fasting blood glucose concentration,sex and age in tree shrews (Tupaia belangeri chinensis)

The tree shrew (Tupaia belangeri chinensis) is a squirrel‐like lower primate or a close relative of primates, commonly used as an animal model in biomedical research. Despite more than three decades of usage in research, the clear relationships between body weight, fasting blood glucose concentration, sex and age among tree shrews remain unclear. Based on an investigation of 992 tree shrews (454 males and 538 females) aged between 4 months and 4 years old, we found that male tree shrews have significantly higher body weight and fasting blood glucose concentration than female tree shrews (p < 0.001). The concentration of fasting blood glucose slightly increased with body weight in males (r = 0.152, p < 0.001). Meanwhile, in females, the body weight, concentration of fasting blood glucose and waist circumference positively increased with age (p < 0.001). Additionally, 17 tree shrews with Lee index [body weight (g)*0.33*1000/body length (cm)] above 290 had significantly higher body weight, waist circumference and glycated haemoglobin A1c (HbA1c) than non‐obese tree shrews with a Lee index score below 290 (p < 0.001). Interestingly, 6 of 992 tree shrews (three males and three females, 2–4 years old) displayed impaired plasma triglycerides, HbA1c, low‐density lipoprotein and oral glucose tolerance test, suggestive of the early symptoms of metabolic syndrome. This study provides the first clear relationships between body weight, fasting blood glucose concentration, sex and age in tree shrews, further improving our understanding of this relationship in metabolic syndrome (MetS). Given the similarity of tree shrews to humans and non‐human primates, this finding supports their potential use as an animal model in the research of MetS.     

瑶山亚种树鼩源嗜水性气单胞菌的分离鉴定及生物学特性研究

为确诊广西中医药大学瑶山亚种树鼩人工驯化养殖中心的瑶山亚种树鼩发病死亡原因,并调查分离菌株的致病性与耐药情况,试验通过平板划线分离获得病原菌,进一步对分离菌进行形态观察、培养特性、生化试验及16S rRNA序列分析,纯化获得一株致病性嗜水性气单胞菌;利用昆明小鼠的致病性试验测定了该分离菌株的半数致死量（LD₅₀）,利用药敏纸片法分析该分离株对常用药物的敏感性,并应用PCR方法进行菌株耐药基因的检测。结果显示,从病死瑶山亚种树鼩分离到一株嗜水性气单胞菌,镜检显示为革兰氏阴性菌,形态呈短杆状。该菌16S rRNA序列与日本淡水湖源嗜水性气单胞菌SWCY-3.27株同源性高达100%,遗传进化关系最近。该分离菌对成年昆明小鼠的LD₅₀为1×10⁷ CFU,毒力高于模式菌株ATCC 7966,近似于中国流行株NJ-35和J-1等,致病性试验鉴定该菌为强毒力菌株。生化鉴定七叶苷、阿拉伯糖、氧化酶呈阳性,各种生化鉴定符合嗜水气单胞菌生化特性。药敏检测显示,该菌株对米诺环素、链霉素、妥布霉素等9种药物敏感,对四环素、红霉素、青霉素等10种药物耐药。以PCR扩增基因方法对分离菌进行6类12种耐药基因的检测,发现分离菌存在氨基糖苷类（Aph-（3）-lia）和β-内酰胺类（mecA）两类抗生素的耐药基因,与药敏试验结果基本吻合。本研究结果表明,引起此次树鼩死亡的病原菌为嗜水性气单胞菌,可用高敏药物进行针对性治疗,为防治嗜水性气单胞菌感染导致的树鼩疾病提供参考依据。     

树鼩源大肠杆菌分离鉴定及耶尔森强毒力岛相关基因的检测及序列分析

【目的】 研究树鼩源大肠杆菌耶尔森强毒力岛（HPI）相关基因的携带情况及其耐药性,为树鼩的饲养管理及大肠杆菌病的防治提供一定思路。【方法】 无菌采集树鼩肛拭子样品129份,采用麦康凯培养基、LB琼脂培养基、革兰氏染色和生化试验进行细菌分离鉴定,用PCR法对分离菌株进行HPI相关基因检测,经PCR鉴定后筛选HPI阳性菌株并对该菌株的主要结构基因irp2和fyuA进行相似性分析和系统发育树构建,采用纸片扩散法对分离菌株进行药敏试验。【结果】 129份树鼩肛拭子样品共分离得到123株大肠杆菌,分离率为95.35%（123/129）;革兰氏染色结果显示,分离菌株镜检为红色粗短杆菌;生化鉴定结果显示,分离菌株对乳糖、葡萄糖、麦芽糖、蛋白胨和甘露醇生化反应呈阳性,硫化氢和尿素酶生化反应呈阴性,均符合大肠杆菌特性;PCR产物电泳结果显示,HPI相关基因检出率为88.62%（109/123）,irp2基因携带率为34.15%（42/123）,fyuA基因携带率为47.97%（59/123）;主要结构基因序列分析结果显示,irp2和fyuA基因与GenBank中公开发表的irp2和fyuA基因序列相似性分别达到98.6%和98.9%以上;系统发育树结果显示,分离菌株与耶尔森菌属亲缘关系较近;耐药性分析结果显示,分离菌株对阿米卡星和氟苯尼考敏感,对阿莫西林和苯唑西林耐药,耐药率分别为87.80%和81.30%。【结论】 HPI相关基因在树鼩大肠杆菌中广泛分布,进一步证实HPI可发生水平转移,且主要结构基因irp2和fyuA的遗传具有较高保守性。     

瑶山亚种树鼩ISG15蛋白表达及其多克隆抗体制备

【目的】克隆瑶山亚种树鼩干扰素刺激基因15(interferon stimulating gene 15,ISG15)基因,在大肠杆菌中高效表达并纯化、制备多克隆抗体,为其生物学应用及检测方法的建立奠定基础。【方法】提取瑶山亚种树鼩外周淋巴细胞总RNA,经RT-PCR扩增出ISG15基因,亚克隆到真核表达载体构建重组真核表达质粒pcDNA3.1-ISG15,并瞬时转染仓鼠肾细胞(baby hamster syrian kidney, BHK-21);同时亚克隆到原核表达载体pET-28a(+)构建重组表达质粒pET-28a-ISG15,转化大肠杆菌BL21(DE3)感受态细胞,IPTG诱导表达树鼩ISG15蛋白;重组蛋白经镍离子亲和层析法纯化并免疫小鼠,获得鼠抗树鼩ISG15多克隆抗体,利用Western blotting和间接免疫荧光技术(IFA)检测其反应性。【结果】成功克隆瑶山亚种树鼩ISG15基因,并构建了其真核和原核表达载体,真核表达载体在BHK-21细胞中能高效表达;原核表达载体在大肠杆菌中30℃、0.5 mmol/L IPTG诱导6 h获得重组蛋白(分子质量22 ku),...     

Immunohistochemical survey of the gut endocrine cells in the common tree shrew (Tupaia belangeri).

Regional distribution and relative frequency of endocrine cells in the gastrointestinal tract of the common tree shrew (Tupaia belangeri) were studied immunohistochemically. Ten types of immunoreactive endocrine cells were localized in the gastric mucosa, i.e., chromogranin-, serotonin-, gastrin-, somatostatin-, bovine pancreatic polypeptide (BPP)-, enteroglucagon-, pancreatic glucagon-, peptide tyrosine tyrosine (PYY)-, motilin-, and substance P (SP)-immunoreactive (IR) cells. In the intestine, 13 types of immunoreactive cells were observed, i.e., chromogranin-, serotonin-, somatostatin-, gastrin-, BPP-, enteroglucagon-, PYY-, secretin-, cholecystokinin (CCK)-, gastric inhibitory peptide (GIP)-, motilin-, neurotensin-, and SP-IR cells. The regional distribution and relative frequency of the cell types varied along the gastrointestinal tract. Basically, the types, distribution, and relative frequency of the gut endocrine cells were similar to those reported in other mammalian species. However, some characteristic findings were noted in the present study: (1) the considerably large number of gastrin-IR cells in the pyloric region; (2) numerous serotonin-IR cells in the stomach; (3) appreciable number of BPP-IR cells in the transitional region of the stomach; and (4) wide distribution of PYY- and motilin-IR cells in the gut.     

Population genomics provides insights into the evolution and adaptation of tree shrews (Tupaia belangeri) in China

Physiological adaptation of tree shrews (Tupaia belangeri) to changing environmental temperature has been reported in detail. However, the T. belangeri origin (mainland or island), population history, and adaptation to historical climate change remain largely unknown or controversial. Here, for the first time, we sequenced the simplified genome of 134 T. belangeri individuals from 12 populations in China and further resequenced one individual from each population. Using population genomic approaches, we first observed considerable genetic variation in T. belangeri. Moreover, T. belangeri populations formed obvious genetic structure and reflected different demographic histories; they generally exhibited high genetic diversity, although the isolated populations had relatively low genetic diversity. The results presented in this study indicate that T. b. modesta and T. b. tonquinia were separated recently and with a similar population dynamics. Second, physical barriers rather than distance were the driving factors of divergence, and environmental heterogeneity may play an important role in genetic differentiation in T. belangeri. Moreover, our analyses highlight the role of historical global climates in the T. belangeri population dynamics and indicate that the decrease of the T. belangeri population size may be due to the low temperature. Finally, we identified the olfaction-associated adaptive genes between different altitude populations and found that olfactory-related genes of high-altitude populations were selectively eliminated. Our study provides demographic history knowledge of T. belangeri; their adaption history offers new insights into their evolution and adaptation, and provides valuable baseline information for conservation measures.