The effect of an L-type calcium channel blocker on the hemodynamics of orbital arteries in dogs

Purpose (1) To determine the effect of the l ‐type calcium channel blocker amlodipine on color Doppler ultrasound‐determined vascular resistance and blood flow velocities in the distal retrobulbar arteries of dogs; (2) to determine any effect of blood pressure and PCO₂ rate on such color Doppler‐determined circulatory measurements. Methods Color Doppler imaging measurements of the short posterior ciliary artery, long posterior ciliary artery, and ophthalmic artery of normal eyes of 10 dogs were obtained under isofluorane anesthesia before and 1 week after oral amlodipine administration. Mean systemic arterial blood pressure and PCO₂ were monitored. Results The mean resistive index decreased significantly in the short posterior ciliary artery (P = 0.0347), in the long posterior ciliary artery (P = 0.0092), and ophthalmic artery (P = 0.0004) following systemic amlodipine administration. The end diastolic velocity increased significantly in the long posterior ciliary artery (P = 0.0368) and ophthalmic artery (P < 0.0001). The peak systolic velocity increased significantly in the ophthalmic artery (P = 0.0256). Mean systemic arterial blood pressure was significantly negatively associated with resistive index (P < 0.0001) and significantly associated with the log of the end diastolic velocity (P < 0.0001). Conclusions Systemically administered amlodipine increases color Doppler imaging‐determined blood flow velocity and decreases vascular resistive index in the ophthalmic artery, short posterior ciliary artery and long posterior ciliary artery of normal dogs. Changes in systemic arterial blood pressure can significantly affect the measurement of color Doppler imaging parameters.     

防疫耳标主要质量指标的检测

本着遵照标准,结合实际的原则,阐述了动物用防疫耳标强度指标和字迹附着力指标等主要质量指标的检测方法,并通过大量试验证实其具有简单、科学、有效等特点,在实际检测过程中具有一定的推广应用价值。     

Motility and Plasma Membrane Integrity of Spermatozoa in Fractionated Stallion Ejaculates after Storage

With the aim of investigating properties of stallion seminal plasma to eventually improve semen-handling techniques, sperm motility and plasma membrane integrity were analysed in different fractions of the ejaculates after storage. Semen was collected using a computer-controlled automated phantom that separates the ejaculates into five successive cups. Samples containing seminal plasma and skim milk extender were compared with samples stored in skim milk extender after the removal of seminal plasma by centrifugation. Fractionated ejaculates were stored cooled for 24 h after dilution with extender (Expt 1) or frozen in liquid nitrogen (Expt 2). In Expt 1, cup 1 was pre-sperm fluid, cups 2 and 3 sperm-rich fractions, and cup 4 sperm-poor fractions. In Expt 2, cups 1 and 2 were sperm-rich fractions, and cups 3 and 4 sperm-poor fractions. One sample (WE) represented the whole ejaculate in both experiments. Motility parameters were determined with a Hamilton-Thorn Motility Analyzer, and plasma membrane integrity was assessed using carboxyfluorescein diacetate and propidium iodide staining and fluorescence microscopy. The removal of seminal plasma lowered motility values, but not plasma membrane integrity, in both experiments. No significant differences between cups were observed after cooled storage. The cups differed significantly in most post-thaw motility parameters, and the sperm-rich fraction showed higher post-thaw motility than the whole ejaculate.     

Elimination of bovine viral diarrhoea virus in New Zealand: a review of research progress and future directions

The major impacts of bovine viral diarrhoea (BVD) on cattle health and production have prompted many countries to embark on national elimination programmes. These programmes typically involve identifying and removing persistently infected (PI) cattle in infected herds and implementing biosecurity measures, such as pre- or post-movement testing. In order to design a systematic national control programme to eliminate BVD in New Zealand, which achieves the greatest benefits to the industries at the lowest cost to individual farmers, an accurate understanding is necessary of the epidemiology, economics and social motivation for BVD control in New Zealand. In this article we briefly review the pathogenesis of BVD, transmission and diagnosis of BVD virus infection, and effectiveness of vaccination. We summarise the current state of knowledge of the prevalence, risk factors for transmission, and financial impacts of BVD in New Zealand. We describe control programmes in Europe and then discuss the challenges that must be addressed to design a cost-effective national control programme to eliminate BVD in New Zealand.