A Single Sample Method for Evaluating 51Chromium-Ethylene Diaminic Tetraacetic Acid Clearance in Normal and Hyperthyroid Cats

Background: Chronic kidney failure is frequently seen in middle-aged and elderly cats. ⁵¹Chromium-ethylene diaminic tetraacetic acid (⁵¹Cr-EDTA) clearance and single blood sample (SBS) method are used in several species to estimate the glomerular filtration rate (GFR).
Hypothesis: The hypothesis of this study was that ⁵¹Cr-EDTA clearance could be determined using an SBS method in normal and hyperthyroid cats.
Animals: Forty-six cats were included in this study, with an average age of 9.5 years. Of these cats, 27 had hyperthyroidism; 19 were healthy.
Methods: After IV injection of ⁵¹Cr-EDTA (average dose: 4.25 MBq), 7 blood samples were obtained between 5 and 240 minutes. Reference clearance was calculated in mL/min and mL/min/kg body weight, using a 2-compartment model. Optimal time for clearance measurement with SBS was then determined by systematically comparing each individual plasma concentration to the reference multisample clearance.
Results: The average reference plasma clearance of ⁵¹Cr-EDTA for all cats was 14.9 mL/min (3.7 mL/min/kg). The clearance in hyperthyroid cats averaged 16.4 mL/min (4.3 mL/min/kg) and in normal cats averaged 10.3 mL/min (2.4 mL/min/kg).
The optimal time for the SBS was 48 minutes after injection of tracer ⁵¹Cr-EDTA ( R ²= 0.9414), giving the following converting equation: clearance = (0.0066 × DV_{48 minutes}) – 0.9277 (in mL/min).
Conclusions and Clinical Importance: In this study, the single sample ⁵¹Cr-EDTA clearance method was used to estimate the global GFR in cats. The method identified differences in clearance between normal and hyperthyroid cats. The optimal time for an SBS was 48 minutes.     

Transmission of methicillin resistant Staphylococcus aureus among pigs during transportation from farm to abattoir

The prevalence of methicillin resistant Staphylococcus aureus (MRSA) in pigs at abattoirs is higher than in pigs sampled on farms. This study investigated whether MRSA negative pigs can become MRSA positive during transportation from the farm to the abattoir after exposure to other pigs and environmental sources of MRSA. Nasal swabs were collected from four batches of pigs during loading at the farm, on arrival at the abattoir and after stunning. Environmental wipes were taken from lorries after transporting pigs and from lairages after holding pigs. All pigs (n = 117) tested MRSA negative before transportation. On arrival at the abattoir, 12/117 (10.3%) pigs in two batches tested MRSA positive. In lorries that tested positive after transportation, the prevalence of MRSA positive pigs was 21.1%, whereas no MRSA was detected in pigs that had been transported in lorries that tested negative after transportation. At stunning, all batches and 70/117 (59.8%) pigs tested MRSA positive. Pigs can become MRSA positive in the short period of time during transportation from the farm to stunning at the abattoir.     

MicroRNA及其对哺乳动物繁殖的影响

卵巢功能的正常维持有赖于卵巢生殖细胞和体细胞之间的相互作用及若干卵巢自分泌和旁分泌的调节.这些调节物质调控卵巢内不同的细胞活动,包括细胞生长、分化和凋亡,从而对卵泡的发育起着至关重要的作用.Micro-RNAs(miRNAs)是一种小的、非编码、21～25 nt长的单链小分子RNA,近年来科学家们发现其在基因表达转录后水平的调控发挥了重要作用.鼠上的研究显示,miRNAs在卵母细胞成熟和卵巢卵泡发育过程中有调控功能.人上的研究也表明,miRNAs影响颗粒细胞中特定的基因表达,并参与卵巢癌的形成和发展.本文将对miRNAs的生物合成,及其在哺乳动物繁殖系统中的表达,正常和病理情况下miRNAs在繁殖系统中可能的调控作用作一综述.     

鸡蛋夏天保存过程中微生物变化比较研究

本研究探讨了鸡蛋在盛夏室内自然条件下,不同储存时间对鸡蛋微生物变化情况的影响。结果表明,鸡蛋外壳和内容物菌落总数随着存放时间(0～25d)延长呈上升趋势,变化范围分别在1.70×104～4.69×105CFU/g和0～9.5×107CFU/mL之间。鸡蛋外壳大肠菌群总数随着时间的延长先不断增加,在第15d检测时数目明显减少,第25d减少更加明显。鸡蛋蛋清和蛋黄混合物的大肠菌群总数在贮藏第1d至第4d并未检测出明显大肠菌群,从第8d随着时间的延长而不断增加,但增幅不大,第25d鸡蛋已完全变质,细菌菌落总数增幅较之前异常明显,多不可计。     

犊牛大肠杆菌病的诊治

2010年5月,黑龙江省双城市某乡先后有3位畜主来我院对其所养的5头犊牛发病情况进行就诊。通过询问得知,这几头犊牛基本都是刚出生半个月左右。病犊发热,精神沉郁或昏迷。间有腹泻,有2头死前发生腹泻,并有明显的脖颈扭转现象。另外2头犊牛发病初期排出黄色粥样粪便,后期排灰白色水样粪     

Studies on Haemonchus contortus. X. The effect of Trichostrongylus axei in Merinos on artificial pastures

A recently established Eragrostis curvula pasture 1,1 ha in size at Hennops River in the Transvaal Highveld was contaminated from 6 October 1976 until 20 May 1977 by 30 weaned Merinos, each infested with 7 000 infective larvae of H. contortus. On 2 November 1976 3 groups of weaned Merinos and again on 10 January 1977 a further group of Merinos were infested with 40 000 infective larvae of Trichostrongylus axei. From 19 November a single group of sheep, predosed with T. axei, and a control group grazed with the seeders for 8 weeks. After 6 weeks another group of sheep dosed with T. axei grazed with them, thus ensuring a 2-week overlap. This continued until autumn, when the last groups were removed. Efficacy against challenge reached Class C (greater than 50% effective against total worm burdens of H. contortus in greater than 50% of sheep) in early summer and autumn, but only reached significant levels of either P less than 0,01 or P less than 0,05 in summer. Peak worm burdens in controls were recorded in early autumn.     

Infarction of the pons and medulla oblongata caused by arteriolar thrombosis in a horse

Infarction of the pons and rostral medulla secondary to arteriolar thrombosis was documented histologically in a 17-year-old mixed-Arabian female horse. Clinically, the animal experienced a sudden onset of a head tilt and subsequent non-controllable seizures. There was no historical, clinical or histological evidence to suggest the presence of infection of Equine Herpesvirus-1 or the feeding of corn contaminated by Fusarium moniliforme.     

非洲猪瘟防控的经验和误区

自从2018年8月我国报告首例非洲猪瘟疫情以来,经过3年多的艰难探索,我们面对非洲猪瘟疫情从最初的恐惧和束手无策,到现在的精准清除和“与狼共舞”,疫情防控从被动应对进入到常态化管理和无疫小区建设阶段;非洲猪瘟可防可控的预测得到了实践证明。但是由于我国幅员辽阔,养猪模式多样,疫情防控水平参差不齐;非洲猪瘟疫情零星散发的风险持续存在。下面就我们的观察和调查,对近年来非洲猪瘟防控上的一些经验和误区进行简要分析。     

Expression of vascular endothelial growth factor and endothelial nitric oxide synthase is increased in the placenta of sheep at high altitude in the Andes

Fetal weight and the placenta of sheep at high altitude (HA) are affected by hypoxia. Placental changes (an increase in placental size and vascularization) are greater in ewes from populations that have lived for several generations at HA than in those exposed during just 1 gestation. This study investigated placental expression of vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS), 2 molecules involved in placental angiogenesis that could be upregulated by hypoxia. Two groups of ewes were maintained at HA (3589 m) during pregnancy: HA-native ewes (group HH) and ewes native to lowlands but moved to HA immediately after the diagnosis of pregnancy (group LH). A control group (LL) was kept at sea level. Near term, placentomes were removed, weighed, and processed for immunohistochemical detection of VEGF and eNOS, as well as for vascular area measurement. Placental weight was significantly higher in the HH group than in the LH and LL groups; between the latter 2 groups there was no significant difference. The placental area occupied by vasculature was significantly greater in both the HA groups than in the LH group; the number of placentomes was greatest in the LL group. The density of VEGF and eNOS in the placentome tissue was significantly greater in both HA groups than in the LL group. Although the density of VEGF was significantly lower in the HH group than in the LH group, no differences were observed in eNOS density between the HH and LH animals. These results demonstrate that chronic hypoxia upregulates the expression of placental VEGF and eNOS, suggesting an important role of these molecules in the placental response to HA hypoxia. In addition, an attenuated response to hypoxia in VEGF synthesis may be part of the long-term process of adaptation to HA.