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Author(s): Janelle A. Jiminez[sup.1,2] , Trina C. Uwiera[sup.3] , G. Douglas Inglis[sup.1] and Richard R. E. Uwiera[sup.2] Background Diseases are often categorized by the organs affected and the resulting clinical [...], Acute and chronic inflammatory diseases of the intestine impart a significant and negative impact on the health and well-being of human and non-human mammalian animals. Understanding the underlying mechanisms of inflammatory disease is mandatory to develop effective treatment and prevention strategies. As inflammatory disease etiologies are multifactorial, the use of appropriate animal models and associated metrics of disease are essential. In this regard, animal models used alone or in combination to study acute and chronic inflammatory disease of the mammalian intestine paired with commonly used inflammation-inducing agents are reviewed. This includes both chemical and biological incitants of inflammation, and both non-mammalian (i.e. nematodes, insects, and fish) and mammalian (i.e. rodents, rabbits, pigs, ruminants, dogs, and non-human primates) models of intestinal inflammation including germ-free, gnotobiotic, as well as surgical, and genetically modified animals. Importantly, chemical and biological incitants induce inflammation via a multitude of mechanisms, and intestinal inflammation and injury can vary greatly according to the incitant and animal model used, allowing studies to ascertain both long-term and short-term effects of inflammation. Thus, researchers and clinicians should be aware of the relative strengths and limitations of the various animal models used to study acute and chronic inflammatory diseases of the mammalian intestine, and the scope and relevance of outcomes achievable based on this knowledge. The ability to induce inflammation to mimic common human diseases is an important factor of a successful animal model, however other mechanisms of disease such as the amount of infective agent to induce disease, invasion mechanisms, and the effect various physiologic changes can have on inducing damage are also important features. In many cases, the use of multiple animal models in combination with both chemical and biological incitants is necessary to answer the specific question being addressed regarding intestinal disease. Some incitants can induce acute responses in certain animal models while others can be used to induce chronic responses; this review aims to illustrate the strengths and weaknesses in each animal model and to guide the choice of an appropriate acute or chronic incitant to facilitate intestinal disease. Keywords: Intestine, Inflammation, Acute, Chronic, Animal models, Incitants, Chemical, Biological

Effects of Beauveria bassiana on non-target arthropods were assessed following field application on rangeland and alfalfa agroecosystems in Canada. Densities and prevalence of B. bassiana within non-target arthropods were measured by two methods, surface sanitation of non-target cadavers followed by homogenisation and plating on selective medium, or incubation in a high humidity environment. From rangeland, numbers of B. bassiana colony-forming units (cfu) in spiders, and carabid and tenebrionid beetles were low (≤2.0 × 103 cfu/ individual) and none of the 2500 arthropods incubated in high humidity were colonised. In alfalfa, increases in numbers of B. bassiana cfu in homogenised specimens were observed only in the first four days in coccinellid beetles (Coccinellidae) while high cfu numbers persisted in some harvestmen (Phalangidae). Laboratory assays with coccinellids indicated that recovered B. bassiana emanated from ingested conidia within the alimentary tracts rather than from hyphal bodies within hemocoels. A relatively low prevalence of non-target arthropods from which B. bassiana was isolated in rangeland and alfalfa coupled with the decrease in numbers of internal cfu as a function of time indicated that the fungus imparted a minor and short-lived impact on non-target arthropods. Although B. bassiana did not affect leafcutting bee larvae, prepupae or adult emergence following overwintering diapause, a small number of foraging bees were infected under field conditions. Measuring internal fungal populations on selective medium or incubation of cadavers in a high humidity environment were found to be convenient and efficient methods for safety assessment to non-target arthropods of a mycopesticide applied under field conditions. [ABSTRACT FROM AUTHOR]

The article presents a study about the molecular methods for the measurement of intestinal bacteria. It mentioned the strengths and weaknesses of the methods. It utilized the advantage of terminal restriction fragment length polymorphism (T-RFLP) to characterize the communities in all samples. It also noted the application of flow cytometry fluorescent in situ hybridization (FCM-FISH) and quantitative polymerase chain reaction (qPCR) in the quantification of groups of bacteria.

As a result of bovine spongiform encephalopathy in Canada, specific tissues at risk of harbouring prions are not allowed to enter the food chain. Composting may be a viable alternative to rendering and land filling for the disposal of specified risk material (SRM). Two types of laboratory-scale composters, actively-heated and ambient systems were constructed to assess the biodegradation of SRM over 30 days. A second heating cycle was generated by mixing the compost after 15 days. Compared to ambient composters, temperature profiles in actively-heated composters were above 50°C for 5 and 4 days longer in the first and second composting cycles, respectively. Degradation of SRM was similar between two composter types during two composting cycles, averaging 52.2% in the first cycle and 43.9% in second cycle. Denaturing gradient gel electrophoresis (DGGE) revealed that changes in the actinobacteria populations in the first composting cycle were of a temporal nature, whereas alterations in populations in the second composting cycle were more related to active heating of compost. Sequencing of the dominant DGGE bands showed the predominance of Corynebacterium, Promicromonospora, Pseudonocardia, and Thermobifida in the first composting cycle and Corynebacterium, Mycobacterium, Nocardia, Saccharomonospora, and Streptomyces in the second composting cycle. Active heating can alter the nature of actinobacteria populations in compost, but does not appear to have a major impact on the extent of degradation of SRM. [ABSTRACT FROM AUTHOR]

The enteric flora of captive whooping cranes ( Grus americana) and sandhill cranes ( Grus canadensis) has not been well described, despite its potential importance in the understanding of both the normal condition of the intestinal physiology of these animals and the altered colonization within disease states in these birds. Nineteen whooping cranes and 23 sandhill cranes housed currently at the Calgary Zoo or its affiliated Devonian Wildlife Conservation Centre (DWCC) in Calgary, Alberta were sampled from October 2004-February 2005 by collecting aerobic and anaerobic cloacal swabs from each bird. There were seven major groupings of bacteria isolated from both species of crane. Gram-positive cocci, coliforms, and gram-negative bacilli were the most prevalent types of bacteria isolated for both crane species, with Escherichia coli, Enterococcus faecalis, and Streptococcus Group D, not Enterococcus the bacterial species isolated most commonly. There was a significant difference in the average number of isolates per individual between the two crane species but no differences between age or gender categories within crane species. Campylobacter sp. were isolated from five whooping cranes. The potential zoonotic pathogen Campylobacter jejuni was isolated from one whooping crane and C. upsaliensis was isolated from a second. Three other isolates were unspeciated members of the Campylobacter genus and likely belong to a species undescribed previously. The evaluation of the enteric cloacal flora of whooping cranes and sandhill cranes illustrates that differences exist between these two closely related crane species, and highlights the potential implications these differences may have for current practices involving captive wildlife. Zoo Biol 0:1-13, 2007. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]