Chronic intestinal pseudo-obstruction in a dog

SUMMARY A three-year-old neutered female Border Collie was presented with in-appetence, vomiting and diarrhoea. Abdominal radiographs revealed an obstructive pattern but no physical obstruction was evident at laparotomy. A diagnosis of chronic intestinal pseudo-obstruction was made based on histopathological changes in intestinal biopsies. Treatment was unsuccessful and the dog deteriorated progressively until euthanased five weeks after presentation.     

瘤胃稳定性脂肪对产后奶牛奶产量、牛奶成份和外周血白细胞数量的影响

选择经产、胎次相同和产奶量相近的荷斯坦奶牛40头,配对分组设计分为对照组和试验组,每组20头。对照组全程饲喂基础日粮,试验组饲喂基础日粮 瘤胃稳定性脂肪。结果:瘤胃稳定性脂肪对奶牛采食量无显著影响(P>0.05);试验组牛产奶量显著升高(P<0.05),乳脂率呈上升趋势(P>0.05),但乳蛋白率未见显著变化(P>0.05);试验组奶牛外周血白细胞总数和淋巴细胞数轻度上升(P>0.05),牛奶SCC呈下降趋势(P>0.05)。结果表明,补充瘤胃稳定性脂肪可提高产奶量,对于改善机体免疫机能有一定的作用。     

The Seismic Structure of the Sun

Global Oscillation Network Group data reveal that the internal structure of the sun can be well represented by a calibrated standard model. However, immediately beneath the convection zone and at the edge of the energy-generating core, the sound-speed variation is somewhat smoother in the sun than it is in the model. This could be a consequence of chemical inhomogeneity that is too severe in the model, perhaps owing to inaccurate modeling of gravitational settling or to neglected macroscopic motion that may be present in the sun. Accurate knowledge of the sun's structure enables inferences to be made about the physics that controls the sun; for example, through the opacity, the equation of state, or wave motion. Those inferences can then be used elsewhere in astrophysics.     

In Vitro Development of Bison Embryos Using Interspecies Somatic Cell Nuclear Transfer

Interspecies somatic cell nuclear transfer (interspecies SCNT) has been explored in many domestic and non‐domestic animal species. However, problems arise during the development of these embryos, which may be related to species‐specific differences in nuclear–cytoplasmic communication. The objectives of this study were to investigate the possibility of producing bison embryos in vitro using interspecies SCNT and assess the developmental potential of these embryos. Treatment groups consisted of cattle in vitro fertilization (IVF) and cattle SCNT as controls and wood bison SCNT, plains bison SCNT and wisent SCNT as experimental groups. Cleavage and blastocyst rates were assessed, and blastocyst quality was determined using total cell number, apoptotic incidence and relative quantification of mitochondria‐related genes NRF1, MT‐CYB and TFAM. These results indicate that embryos can be produced by interspecies SCNT in all bison species/subspecies (13.34–33.54% blastocyst rates). Although increased incidence of apoptosis was observed in bison SCNT blastocysts compared to cattle SCNT controls (10.45–12.69 vs 8.76, respectively) that corresponded with significantly lower cell numbers (80–87 cells vs >100 cells, respectively), no major differences were observed in the expression of NRF1, MT‐CYB and TFAM. This study is the first to report the production of bison embryos by interspecies SCNT. Blastocyst development in all three bison species/subspecies was greater than the rates obtained in previous studies by IVF, which supports the potential role of SCNT for in vitro embryo production in this species. Yet, further investigation of developmental competence and the factors influencing blastocyst quality and viability is required.     

Maturation Status, Protein Synthesis and Developmental Competence of Oocytes Derived from Lambs and Ewes

The efficacy of oocyte selection for in vitro embryo production depends on the abundance and diameter of follicles, cumulus layers around the oocytes and subsequent fertilization. Application of `ovum pick-up' technique allows us to utilize partially matured oocytes for embryo production even from juvenile subjects. To compare their developmental competence, oocytes derived from lambs and ewes and cultured in maturation medium for up to 26 h were assessed at 2 h intervals by confocal microscopy after chromatin and microtubulin-specific fluorochrome labelling. Lamb oocytes reached second meiotic metaphase (MII) at lower numbers at 24 h (60.0%) and 26 h (28.6%) whereas 85.7% of adult-derived oocytes attained MII status by 24 h of maturation. Radiolabelling of oocyte proteins revealed higher incorporation of [³⁵S-]-methionine and [³⁵S]-cysteine in adult-derived oocytes compared to lamb oocytes. Although the cleavage rate of lamb oocytes was similar to that of ewe oocytes, the proportion reaching blastocyst stage was significantly lower (p < 0.05) in the lamb-derived oocytes. However, blastocysts from both types of oocytes displayed similar cell lineage allocations to inner cell mass and trophectoderm.     

Effects of drug residues in the faeces of cattle treated with injectable formulations of ivermectin and moxidectin on larvae of the bush fly, Musca vetustissima and the house fly, Musca domestica

Objective: To assess the toxicity of residues of ivermectin and moxidectin in cattle faeces collected at intervals after treatment.
Design: Replicated bioassays of faeces using larvae of the bush fly, Musca vetustissima and the house fly, Musca domestica .
Animals: Two groups of five Murray Grey x Aberdeen Angus steers were treated with injectable formulations of ivermectin and moxidectin respectively. A third group was used as an untreated control.
Procedure: Newly emerged fly larvae were reared in the dung of treated animals.
Results: Drug residues in faeces collected 3 to 35 days after treatment with an injectable formulation of moxidectin had no significant effect on the survival of larvae of M vetustissima . Similarly, faeces dropped up to seven days after treatment caused no significant reduction in larval survival in M domestica . In day 2 dung, residues of moxidectin delayed development of M vetustissima larvae, but had no effect on their survival. In contrast, ivermectin-treated steers, produced dung that inhibited larval development of both M vetustissima and M domestica for 7 to 14 days after treatment. Significant reductions in survival of M vetustissima larvae occurred in dung collected on days 21 and 28 after treatment, but by day 35 survival did not differ from that in control dung.
Conclusion: Excreted faecal residues of moxidectin are relatively innocuous to larvae of both M vetustissima and M domestica . Those of ivermectin inhibit survival for 7 to 14 days after treatment and are likely to have adverse effects on non-target organisms.     

气相色谱-串联质谱法快速检测当归中102种农药残留

建立了当归中102种农药残留的快速检测方法。样品采用优化的QuEChERS前处理方法，利用气相色谱-串联质谱 (GC-MS/MS) 检测，动态多反应监测 (dMRM) 模式，基质匹配外标法定量。结果表明:在样品前处理过程中，经对提取溶剂、提取体系、净化体系的组成和用量进行筛选优化后，样品采用乙腈、1.0 g氯化钠、4.0 g无水硫酸镁、1.0 g柠檬酸钠和0.5 g柠檬酸二钠盐提取，无水硫酸镁800 mg、PSA 150 mg、C₁₈ 150 mg净化，通过基质匹配外标法校正，当归中基质效应对目标化合物的定性、定量影响明显减弱。在0.02~0.64 mg/kg范围内，102种农药的质量浓度与对应的峰面积间呈良好的线性关系，R2均大于0.99，检出限为0.002 5~0.025 mg/kg，定量限为0.005~0.05 mg/kg；在0.04、0.08和0.32 mg/kg 3个添加水平下，102种农药的平均回收率为52 %~128%，RSD为1.0%~10 %。该方法快速简便、耗时短，具有良好的灵敏度、正确度和精密度，为提高当归中农药安全水平，降低健康风险提供了一种快速、高效、可靠的分析手段。     

日粮核苷酸对早期断奶小鼠肝脏基因表达的影响

研究了日粮核苷酸对早期断奶小鼠肝脏基因表达的影响:选取16～17日龄健康BALB/C雄性小鼠60只,分成对照组和实验组,分别饲喂添加0、0.25%核苷酸的无核苷酸基础日粮,在实验的第2、4、10天采用差异显示技术分离小鼠肝脏中差异表达的基因。结果表明:采用6对引物分离到4条差异表达的基因片断。采用差异显示技术初步分离到4个受核苷酸影响差异表达的基因,这些片段需要做进一步的验证。