Morphological and quantitative study of spirochetes in the feces of normal and infected SPF pigs during the incubation period of swine dysentery.

Spirochetes found in feces of normal and infected pigs during the eight days preceding the onset of the clinical signs of swine dysentery have been studied using electron and phase contrast microscopy. According to their dimensions, diameter, length and pitch, three morphological groups have been described: small, intermediate and large spirochetes. On the basis of their axial filaments arrangement, eight types have been observed. Compared to the control pigs, there was no increase in the total number of spirochetes in infected pigs, except at day 6 before the onset of clinical signs. However, infected pigs have shown a wide spectrum of different morphological types of spirochetes in comparison to control, uninfected pigs, which showed only the type "1-2-1" spirochete of axial filaments arrangement. This last type was predominant in infected swine during the entire incubation period as compared to other spirochete types described.     

Use of Asian selected agricultural byproducts to modulate rumen microbes and fermentation

In the last five decades, attempts have been made to improve rumen fermentation and host animal nutrition through modulation of rumen microbiota. The goals have been decreasing methane production, partially inhibiting protein degradation to avoid excess release of ammonia, and activation of fiber digestion. The main approach has been the use of dietary supplements. Since growth-promoting antibiotics were banned in European countries in2006, safer alternatives including plant-derived materials have been explored. Plant oils, their component fatty acids,plant secondary metabolites and other compounds have been studied, and many originate or are abundantly available in Asia as agricultural byproducts. In this review, the potency of selected byproducts in inhibition of methane production and protein degradation, and in stimulation of fiber degradation was described in relation to their modes of action. In particular, cashew and ginkgo byproducts containing alkylphenols to mitigate methane emission and bean husks as a source of functional fiber to boost the number of fiber-degrading bacteria were highlighted. Other byproducts influencing rumen microbiota and fermentation profile were also described. Future application of these feed and additive candidates is very dependent on a sufficient, cost-effective supply and optimal usage in feeding practice.     

Über die Bedeutung von Mycoplasmen als Sterilitätsursache beim Rind*

A review of the literature is presented on the strains of Mycoplasma isolated from the bovine genital tract and their relationship to infertility. Although Mycoplasmas have frequently been isolated from the genital organs of bulls, no typical clinical symptoms have been observed and no detrimental effects on spermatozoa have been shown. Mycoplasmas can be transmitted to cows by artificial insemination. In contrast to bulls, Mycoplasmas have been described as causing inflammatory changes such as cervicitir, endometritis and salpingitis in cows. Salpingitis, which may lead to obstruction of the oviduct, has the most serious consequences of later infertility. The author's own observations on the occurrence of Mycoplasmas in the herds in one area are briefly described. Prophylactic and therapeutic measures against genital Mycoplasma infections in cattle are also given.     

Health effects of lactic acid bacteria ingested in fermented milk

Health effects of lactic acid bacteria ingested in fermented milk. Many recent studies have shown the health effects of various strains of lactic acid bacteria in humans and animals and have tried to describe their action mechanism in the digestive tract. A number and a variety of potential beneficial effects have been published. Some of these effects have already been described such as the improvement of lactose digestion and the treatment of diarrheal disorders. Other health effects are still a subject of controversy such as the decrease of serum cholesterol and the reduction of tumor formation. The aim of this article is to summarize the probiotic effects of lactic acid bacteria, their mechanisms, and the fate of these microorganisms during their transit in the digestive tract.     

禽类基因工程重组干扰素研究进展

近年来 ,多种禽类干扰素基因已被克隆和在大肠杆菌中表达。禽类基因工程重组干扰素在抗马立克病毒、劳斯肉瘤病毒、新城疫病毒、传染性法氏囊病病毒、传染性支气管炎病毒和禽流感病毒方面效果显著 ,展现出了广阔的应用前景。文章对禽类基因工程重组干扰素的研究进展作了综述     

Studies on glutamic acid decarboxylase from Listeria monocytogenes.

The isolation and characterization of glutamic acid decarboxylase from Listeria monocytogenes has been described. Effects of various concentrations of glutamic acid as a substrate and pyridoxal phosphate as coenzyme on the activity of the partially purified enzyme have been examined and their Km and Vmax values determined. The enzyme exhibits relatively higher activity in 0.1 M pyridine-pyridine hydrochloride buffer with a pH value of 4.6.     

A removable orthodontic device for the treatment of lingually displaced mandibular canine teeth in young dogs

The malocclusion of lingually displaced mandibular canine teeth is a common orthodontic problem in the domestic dog. Several treatment methods have been described, and their advantages and disadvantages have been extensively reviewed. This article describes a functional technique used in 38 dogs of different breeds for correction of the malocclusion. The technique consists of stimulating the dog to play with specific toys. It is a simple, inexpensive, non-invasive technique that has a success rate comparable to conventional orthodontic techniques for treatment of this common malocclusion.     

Classification and grading of canine mammary tumors

Mammary neoplasms are the most common neoplasm in female dogs. Two histologic classification systems for canine mammary tumors and dysplasias have been published: the first in 1974 and a modification in 1999. This article provides a brief overview of the two histologic classification systems. Since the publication of the second system, several new histologic subtypes of canine mammary neoplasms have been described. These have been incorporated into the proposed new classification system. This article also compares the grading systems for canine mammary carcinomas and their use for prognosis, along with the histologic classification.     

Isolation and typing of Clostridium oedematiens (Cl. novyi) from cases of black disease of sheep in Iran

Clostridium oedematiens types A, B and D have been isolated from liver lesions of 44 cases of black disease of sheep in Iran. The technique of isolation and identification by using fluorescent labelled antibodies is described. The isolates were typed based on their lecithinase, haemolytic, necrotic and lethal activities.     

The ecology of Escherichia coli in animals including man with particular reference to drug resistance

The phenomenon of drug resistance among bacteria, particularly Escherichia coli, has been a major research interest of the University of Bristol's departments of microbiology and veterinary medicine during the past 15 years. Tens of thousands of E coli isolates from man and farm animals have been examined in studies of both the ecology of the species and the epidemiology of their resistance to therapeutic antibacterial agents. The principal findings obtained in these investigations are described.     

Organophosphorus compounds. I. Toxicity in domestic animals

Organophosphorus compounds with various aspects of their modes of action, toxicity and antidotal treatment have been briefly reviewed. Their clinical, pathological and biochemical effects on different species of domestic animals are also described.     

Canine filariasis caused by Dirofilaria repens in southeastern Nigeria

Many species of canine filarial nematodes and their microfilariae have been described in various parts of the world. At the present time, it would appear that in Nigeria, the canine filarial species of importance is Dirofilaria repens. The parasite and its microfilariae appear to produce toxic and immunologic actions which are responsible for many pathological lesions.     

Evaluation of the cell-mediated immune response in cattle induced by 2,4-dinitrochlorobenzene

A technique has been evolved and standardized for evaluating the cell-mediated immune (CMI) response in cattle induced by 2,4-dinitrochlorobenzene (DNCB). Six healthy cross-bred Jersey cows were used. The dose and the number of applications for primary sensitization and the challenge dose after the 14th day have been standardized. The gross and histological pictures of the CMI response shown by these cattle are described in detail and their usefulness in assessing the CMI response in various disease conditions including tumour is indicated.     

Action of immunostimulants on phagocytosis and derivative actions

One of the main objectives of immunopotentiators is their ability to enhance or to restore natural anti-infectious resistance of normal or immunocompromised hosts. Numerous experimental resistance models have been used in screening such potentiators. However, once such a substance has been selected, its potential and practical use will directly depend on the knowledge of the underlying resistance mechanisms induced, defining its cellular or molecular targets. Phagocytosis-polymorphonuclear or monocyte-macrophage dependent--is the most frequently described variable which have been analysed among the various potentially active mechanisms of non-specific resistance. Various in vivo and in vitro tests might be used and the target of several immunostimulants among the different steps of phagocytosis are described. However, numerous intrinsic limitations are associated with such tests and news models or tests are presented and discussed in order to gain more insights into the evaluation of active substances.     

Recently described scrapie-like encephalopathies of animals: case definitions.

Since 1986, naturally occurring scrapie-like encephalopathies have been described in the United Kingdom in domestic cattle, in five species of captive exotic bovids and in domestic cats. The disease in domestic cattle, bovine spongiform encephalopathy, has been characterised by all currently available diagnostic criteria as a transmissible spongiform encephalopathy or 'prion' disease, and has been shown to have a dietary origin. The pathology in the other species is also entirely consistent with the scrapie-like diseases. The contemporaneous occurrence in the UK of such disease in these species suggests a close epidemiological association. The diagnostic criteria of the scrapie-like encephalopathies of animals are reviewed in the light of experience with the recent extension of their natural host range.     

Sur les variations morphologiques et architecturales des reins des oiseaux domestiques (Gallus domesticus, Meleagris gallopavo, Anser domesticus, Anas boschas domestica)

On the Morphological and Architectural Variations of the Kidneys in Domestic Fowls The investigations have been carried out on kidneys injected with latex and corroded in HCl. The kidneys were taken from 3 cocks, 20 hens, 2 turkey-cocks, 4 turkey hens, 2 drakes, 5 ducks, 5 ganders and 3 geese at the age of 6 months to 1 year. The territorial distributions of the renal vessels are similar in all the four species. Venous “by-pass” and anastomosis not mentioned in the literature have been described. The renal arteries manifest a high degree of variability concerning their origins and ramifications. Our hypothesis of the “longitudinal traction” correlates the “contracted” and “elongated” forms of the kidneys and their architectonics with the longitudinal development of the pelvis, i. e. the adaptation of the apparatus locomotorius to the living conditions of the species.     

A brief review on the laboratory diagnosis of leptospirosis

Leptospirosis is a ubiquitous zoonotic disease that may be maintained in either wild or domesticated animal species. These bacteria have been classified into serovars based on their antigenic characteristics and, more recently, into species based on genomic studies. They produce both chronic and acute infections. Chronic infections of serovars in the host species to which they have become adapted can result in long term shedding, providing a source of acute infection for other species. As clinical presentation can vary greatly, diagnosis often depends on laboratory methods. In addition to diagnostic testing, herd health monitoring and screening for international trade purposes are performed at veterinary laboratories. The test method selected varies depending on the samples available and the purpose of testing. An increasing variety of laboratory methods are being described for detection of bacteria and antibodies. In addition to classical methods such as culture, dark-field, microscopy and the microscopic agglutination test (MAT), a variety of polymerase chain reaction (PCR), indirect enzyme-linked immunosorbent assay (ELISA), competitive ELISA and other rapid serological tests have been described. This review describes the advantages and limitations of these assays together with other factors that may affect results and their interpretation, such as species variation, vaccination and antibiotic administration.     

The broad spectrum of Trichinella hosts: from cold- to warm-blooded animals

In recent years, studies on Trichinella have shown that the host range is wider than previously believed and new Trichinella species and genotypes have been described. Three classes of vertebrates are known to act as hosts, mammals, birds and reptiles, and infected vertebrates have been detected on all continents but Antarctica. Mammals represent the most important hosts and all Trichinella species are able to develop in this vertebrate class. Natural infections with Trichinella have been described in more than 150 mammalian species belonging to 12 orders (i.e., Marsupialia, Insectivora, Edentata, Chiroptera, Lagomorpha, Rodentia, Cetacea, Carnivora, Perissodactyla, Artiodactyla, Tylopoda and Primates). The epidemiology of the infection greatly varies by species relative to characteristics, such as diet, life span, distribution, behaviour, and relationships with humans. The non-encapsulated species Trichinella pseudospiralis, detected in both mammals (14 species) and birds (13 species), shows a cosmopolitan distribution with three distinguishable populations in the Palearctic, Nearctic and Australian regions. Two additional non-encapsulated species, Trichinella papuae, detected in wild pigs and saltwater crocodiles of Papua New Guinea, and Trichinella zimbabwensis, detected in farmed Nile crocodiles of Zimbabwe, can complete their life cycle in both mammals and reptiles. To the best of our knowledge, T. papuae and T. zimbabwensis are the only two parasites known to complete their entire life cycle independently of whether the host is warm-blooded or cold-blooded. This suggests that these two Trichinella species are capable of activating different physiological mechanisms, according to the specific vertebrate class hosting them.     

Molecular genetic methods in the veterinary clinical bacteriology laboratory: current usage and future applications

In the last 5 years, numerous molecular methods have been published for the detection and characterization of bacteria in the field of veterinary medicine. PCR has been the most commonly used technology. Although not currently used for clinical veterinary diagnosis, new technologies such as liquid-phase hybridization, real-time PCR, pathogen load determination and DNA/protein microarray have been described and have many possible applications in the clinical bacteriology laboratory because of their sensitivity and efficiency. This review describes the basic principles and application of recently published DNA-based molecular techniques for the purpose of veterinary clinical bacteriological diagnosis. It covers advances in probe hybridization technology, DNA/RNA amplification techniques and other molecular detection methods, including 16S rRNA analysis for bacterial characterization and DNA microarrays for bacterial detection. The review briefly summarizes the application of molecular methods for the diagnosis of specific important bacterial infections of animals, and for other animal pathogens that are slow or difficult to isolate in the clinical bacteriology laboratory. In addition, the molecular detection of antimicrobial resistance genes and of bovine mastitis pathogens is briefly described and current commercially available tests are listed.     

Endocrine tumors.

Because of the diverse nature of endocrine organs, and their vast range of physiologic functions, endocrine tumors encompass a wide range of origination sites and disease entities. The clinical picture of affected individuals is highly dependent on the tissue of origin, and the presence or absence of functional hormone secretions. Identification, localization, and therapeutic strategies, as well as prognosis can vary greatly. Many endocrine tumors have been described in human as well as veterinary patients. This article focuses on endocrine tumors of dogs and cats. Various tumors affecting the pancreas, thyroid, parathyroid, adrenal and pituitary glands are described, including insulinoma, gastrinoma, glucagonoma, and thyroid carcinoma, as well as parathyroid hormone- and growth hormone-secreting tumors. The syndrome of multiple endocrine neoplasia is also described.