Development of the Mouse Anterior Commissure: Part II: A Comparison of Glial Differentiation in the Anterior and Posterior Limbs of the Anterior Commissure of the Mouse Brain during Myelination using Semithin Light Microscopic Sections

The percentage of glioblasts, oligodendrocytes, astrocytes and microglia in the anterior and posterior limbs of the mouse anterior commissure during myelination was estimated from semithin, toluidine blue stained sections using the criteria of LING et al. (1973). From 11 to 25 days glial differentiation was more advanced in the anterior limb, but from 35 days the percentage of each type of glial cell was similar in each limb. The percentage of microglia was similar in each type of glial cell was similar in each limb. The percentage of microglia was similar in each limb and remained constant from 11 to 240 days. The percentage of astrocytes was similar in each limb at each age, but increased from 10% at 11 days to 20% at 35 days, when it became constant. The percentage of oligodendrocytes was higher in the anterior limb from 11 to 24 days, and continued to increase in both limbs up to 240 dyas. The precentage of dark oligodendrocytes increased with age, while the percentage of light and medium oligodendrocytes declined. Oligodendrocyte differentiation corresponded closely with myelination in each limb.     

Development of the Mouse Anterior Commissure: III. Changes in Total Number of Neuroglia, Mitotic Cells and Dead Cells in the Anterior and Posterior Limbs with Age

The increase in glial numbers, cell density, mitotic index and necrotic index was compared and contrasted in both limbs of the anterior commissure of the developing mouse brain. At birth the anterior limb contained fewer cells than the posterior, but by 8 days the cell totals in both limb were similar, and thereafter there were always significantly more cells in the anterior limb. Glial proliferation appeared to cease earlier in the posterior limb. The mitotic indices were similar in both limbs declining steadily from birth except for a slight increase between 11 and 14 days in the anterior limb and at 14 days in the posterior. The necrotic index reached a maximum from 5 to 8 days in the posterior limb, and from 8 to 11 days in the anterior limb. A further small peak occurred in the posterior limb at 21 days, and in the anterior limb at 25 days. Except at birth glial density was always significantly higher in the posterior limb, and it is suggested that this may be due to the greater requirement for the removal of K+ ions from the less highly myelinated posterior limb.     

Development of Myelination in the Bovine Fetal Brain: an Immunohistochemical Study

In this study, the development of myelination in the fetal bovine brain (age-range: between 1–2 and 8–9 months) was examined applying: 1. Immunohistochemical staining methods and antibodies against bovine proteolipid protein (PLP), synthetic tridecapeptide of bovine PLP, human myelin basic protein (MBP), human myelin-associated glycoprotein (MAG); and 2. Using the Luxol fast-blue (LFB) technique.     

大熊猫和小鼠精子在获能过程中各部元素相对含量的X射线微区分析

采用扫描电镜ｘ射线微区分析方法，对获能前、后大熊猫射出精子和小鼠附睾尾精子头前、后部和尾中段Ｃａ、Ｍｇ、Ｋ、Ｚｎ、Ｃｌ、Ｐ和Ｓ等７种元素的相对含量进行了测量。统计结果表明：（１）大熊猫精子获能前头前部Ｃａ相对含量较头后部高，但小鼠精子头后部较头前部高。获能后２种动物精子头前、后部Ｃａ相对含量无显著差异；（２）小鼠精子头前部Ｃａ相对含量在获能过程中升高，而大熊猫精子头前部Ｃａ相对含量无显著变化；（３）大熊猫和小鼠精子获能过程中头部Ｋ相对含量均显著增加；（４）小鼠精子获能过程中头部和尾中段Ｓ相对含量显著升高，而大熊猫精子无这种变化；（５）大熊猫和小鼠精子相比，Ｃａ、Ｐ相对含量较高，Ｃｌ、Ｓ和Ｋ相对含量较低。本文对这些统计结果进行了讨论。     

Eosinophils of the horse: Part I: Development,distribution, structure and biochemical mediators

Eosinophils are becoming the target of increasing research interest as recent studies suggest that their role in immune homoeostasis and the immune response to disease is far more complex than previously understood. Historically, the horse eosinophil has been used to study basic eosinophil biology because of the considerable volume of blood required to obtain enough viable cells for reliable, repeatable experiments. This resulted in a large but disseminated body of literature pertaining to the structure and function of the horse eosinophil. More recently, equine clinicians have produced case reports and clinical studies in an effort to define the role of the eosinophil in diseases of the horse. A thorough review of the equine eosinophil incorporating both bench research and clinical reports does not exist. The objective of this two-part review is to fill this need by integrating the basic science and clinical research into a comprehensive body of work on what is known specifically about the horse eosinophil, and its role in equine health and disease. Part I summarises the development and tissue distribution of eosinophils in the normal horse, and presents what is known about the cell structure, migration and biochemical mediators of the horse eosinophil. Part II reviews the role of the eosinophil in diseases of the horse, and concludes with a summary of knowledge gaps and open research questions to benefit both those who wish to use the equine eosinophil as a model for basic science research, and those whose primary interest lies with diseases of horse.     

家兔与大鼠胫骨前肌的生后发育

为探讨家兔、大鼠胫骨前肌在生后各日龄阶段前、后亚体内快慢肌纤维的发育情况，应用大体解剖结合组织化学法明确其肌亚体，并作琥珀酸脱氢酶（SDH）染色，图象分析两型肌纤维的直径特征。用电生理记录仪，分别测量肌前、后亚体功能。结果表明：家兔与大鼠各肌亚体划分在生后发育中逐渐分界清楚，生后2、3天均未能分出Ⅰ、Ⅱ型肌纤维，也未见有原始肌束。Ⅰ、Ⅱ型肌纤维比例随年龄增长而变化，Ⅱ型纤维比例增大。Ⅱ型纤维直径均大于Ⅰ型纤维，葡萄状运动神经末梢支配慢肌纤维，斑点状运动终板位于快肌纤维，前后肌亚体诱发电位表明其特殊的功能。     

重度联合免疫缺陷（SCID）小鼠性机能发育的初步研究

本研究对ＳＣＩＤ小鼠与ＢＡＬＢ／ｃ小鼠的阴道开口时间,卵泡发育,精子发生及血浆促黄体素（ＬＨ）和睾酮（Ｔ）浓度进行了比较观察,结果表明,２种鼠阴道开口时间均为４０日龄,均在３０日龄时卵巢出现有腔卵泡,但ＳＣＩＤ雌鼠４５日龄有排卵,而同龄ＢＡＬＢ／ｃ雌鼠未见排卵;ＳＣＩＤ雄鼠４０日龄附睾涂片有活精子,ＢＡＬＢ／ｃ雄鼠４５日龄附睾涂片可见活精子,ＳＣＩＤ小鼠初情期似乎有比ＢＡＬＢ／ｃ小鼠初情期略早的趋     

Bovine Posterior Pituitary Extract Stimulates Prolactin Release from the Anterior Pituitary Gland In Vitro and In Vivo in Cattle

It has been reported that the posterior pituitary (PP) gland contains a potent, unknown prolactin (PRL)-releasing factor (PRF) in rats. PRFs are assumed to be produced in neurones located within the hypothalamus, and to be peptidergic in nature. However, little is known about PRFs in domestic animals. To characterize the PRF in the PP of domestic animals, the present study examined the PRL-releasing activity of an acidic extract from bovine PP (bPP) in vitro and in vivo in cattle. First, the PRL-releasing effect of bPP extract was compared with that of PRL-releasing peptide (PrRP), and thyrotropin-releasing hormone (TRH) from cultured bovine anterior pituitary cells. The extract significantly increased PRL concentrations in the culture medium, at doses of 0.002 and 0.02 eq./ml (one eq. is the PP extract from one animal), compared with the control (p < 0.05). PrRP failed to stimulate the release of PRL. TRH significantly increased PRL concentrations in the culture medium, at doses from 10(-9) to 10(-7) M, compared with the control (p < 0.05). The rate of increase in the PRL concentration, by 0.02 eq./ml bPP extract, was significantly greater than that in TRH (p < 0.05). Secondly, plasma PRL responses to the intravenous (i.v.) injection of bPP extract (0.5 eq./head), PrRP [3.59 mug/kg body weight (BW)], TRH (1 mug/kg BW), and a dopamine receptor antagonist (sulpiride, 0.1 mg/kg BW), were examined in calves. PrRP failed to stimulate PRL release; however, plasma PRL increased immediately following the injection of bPP extract, TRH and sulpiride. The PRL-releasing effect of i.v. injections of TRH and sulpiride was more potent than that of bPP extract. Finally, plasma PRL responses to the intra-hypothalamic injection of bPP extract were examined in calves. The intra-hypothalamic infusion (arcuate nucleus) of 0.0625 eq./head of bPP extract strongly stimulated PRL release in calves (p < 0.05). The present results show that PP contains a physiologically potent PRF in cattle.     

A Comparison of the Viruses of Infectious Bovine Rhinotracheitis (IBR), Infectious Pustular Vulvovaginitis (IPV), and Rinderpest: Part I. Studies of Antigenic Relationships

The viruses of infectious bovine rhinotracheitis (IBR), infectious pustular vulvovaginitis (IPV), and rinderpest were compared by specific methods. The results further confirmed that IBR and IPV are caused by agents with common antigens. No antigenic relationship was found between these viruses and rinderpest virus, which confirms earlier work.     

Part I: twenty-year literature overview of veterinary and allopathic medicine

Over the last 20 years, numerous reports, symposia, and workshops have focused on the challenges and changes facing veterinary and allopathic medicine. Many of these have specifically considered the changing economic and demographic profiles of the health professions, the specific roles of health professionals in society, and the importance of professional curricula in meeting changing professional and societal needs. Changing curricula to address future demands is a common thread that runs through all of these reports. Future demands most consistently noted include the fact that modern veterinary curricula must emphasize the acquisition of skills, values, and attitudes in addition to the acquisition of knowledge. Skills relating to business management, strong interpersonal communication, and problem solving have often been noted as lacking in current curricula. Furthermore, future curricula must allow for greater diversification and "specialization" among veterinary students; should promote greater opportunities for an emphasis on public health and population medicine, including food safety, food security, and bio- and agro-terrorism; and should motivate students to be active learners who possess strong lifelong learning skills and attitudes.     

Muscle Contractures in the Limbs of Dogs and Cats

Muscle contractures causing varying degrees of lameness commonly occur from skeletal muscle fibrosis, the result of injury such as that caused by circulatory insufficiency, infection, autoimmune reaction, or trauma. Quadriceps contracture, whether congenital or acquired, is treated by sectioning the cordlike fibrotic muscle group by "Z" plasty, resulting in lengthening it enough to allow the knee to assume a normal standing angle. Adhesion of the muscle group to a large femoral callus (muscle tie down) may occur and require additional surgical correction. Infraspinatus contracture results in a typical foreleg deformity and change in gait. Surgical repair by tenotomy is usually followed by rapid return to normal. Gracilis contracture, though common in racing greyhounds, is not commonly reported in pet dogs. Surgical excision of the entire affected muscle mass is curative.     

Comparison of Three Skin Preparation Techniques in the Dog Part 1: Experimental Trial

Premeasured, clipped areas of skin on both sides of 30 adult dogs were prepared with povidone-iodine (PI), chlorhexidine gluconate (CG) with a saline rinse, or 4% CG with a 70% isopropyl alcohol rinse. Skin bacteria were quantified with Replicating Organism Detection and Counting (RODAC) plates and cultured for identification before, immediately after, and 1 hour after skin preparation. The percentages of bacterial reduction immediately and at hour 1 and the percentages of negative cultures, cultures with more than five colony-forming units (CFUs), and skin reactions were analyzed by analysis of variance and chi-square. The percentage of reduction in skin bacteria for all techniques was significant and comparable with that reported in humans. There were no significant differences between PI and CG results except that acute contact dermatitis was observed more frequently after skin preparation with PI. The authors conclude that for similar application times, PI and 4% CG rinsed with saline or 70% isopropyl alcohol are equally effective for up to 1 hour in the preoperative skin preparation of dogs.     

A HACCP-based approach to mastitis control in dairy herds. Part 1: Development

Hazard Analysis and Critical Control Points (HACCP) systems are a risk based preventive approach developed to increase levels of food safety assurance. This is part 1 of a pilot study on the development, implementation and evaluation of a HACCP-based approach for the control of good udder health in dairy cows. The paper describes the use of a novel approach based on a deconstruction of the infectious process in mastitis to identify Critical Control Points (CCPs) and develop a HACCP-based system to prevent and control mastitis in dairy herds. The approach involved the creation of an Infectious Process Flow Diagram, which was then cross-referenced to two production process flow diagrams of the milking process and cow management cycle. The HACCP plan developed, may be suitable for customisation and implementation on dairy farms. This is a logical, systematic approach to the development of a mastitis control programme that could be used as a template for the development of control programmes for other infectious diseases in the dairy herd.     

Conservation of feline semen. Part I: cooling and freezing protocols

There has been increased interest recently in the conservation of wild felids and preservation of valuable cat breeds. Assisted reproduction, by means of artificial insemination (AI), is an important tool for developing breeding programs for conservation. Optimal use of AI requires accurate data on semen conservation protocols and its long-term storage/survival. In this paper, semen cooling and freezing processes are described, with special emphasis on the results obtained in experiments performed in the domestic cat. Conception rates after AI in wild and domestic cats are also reported.