Defining important canine zoonotic pathogens within the Prairie Provinces of Canada

The goal of this study was to establish a short list of zoonotic pathogens involving the domestic dog that can be prioritized for a companion animal surveillance program specific to the Prairie Provinces of Canada. A list of pathogens documented in dogs was created through a comprehensive review of infectious disease textbooks for the following taxonomical categories: bacteria, ectoparasites, fungi, helminths, protozoa, rickettsia, and viruses. This created an initial list of 594 pathogens that was then pared down through an extensive review of the literature using the following criteria: i) the pathogen is zoonotic/sapronotic/anthroponotic; ii) the dog is involved in transmission to humans, maintenance, or detection of the pathogen; and iii) there is a level of risk for occurrence of the pathogen in Canada. This process yielded a final list of 84 pathogens and 3 supplementary lists of canine zoonotic/sapronotic/anthroponotic pathogens that may become relevant to future surveillance programs.     

Early growth and development of silver birch (<Emphasis Type="Italic">Betula pendula</Emphasis> Roth.) plantations on abandoned agricultural land

Eight-year-old plantations (11) of silver birch were studied on abandoned agricultural land in Estonia. Trees were planted on uncovered soil and on polyethylene. After eight growing seasons, the height and diameter at breast height of the trees grown on polyethylene were significantly (P < 0.001) larger than corresponding parameters of the trees grown on uncovered soil. The annual height increment of the birches grown on the polyethylene was significantly (P < 0.05) larger during six growing seasons after planting compared to that of the trees grown on uncovered soil. However, annual height increments were not significantly different in the 7th and the 8th growing seasons. The use of polyethylene mulching had a statistically significant effect (P < 0.001) on the height of the beginning of the live crown in 8-year-old plantations. The differences between the values of live crown ratio of the trees grown on polyethylene and the values of live crown ratio of the trees grown on uncovered soil decreased during six growing seasons. However, by the 7th and 8th growing seasons, there was no significant difference (P > 0.05) between the values of the live crown ratio. The height growth of silver birch grown without mulching as well as with mulching was found to be more intensive on Glossic Podzoluvisol, Calcaric Cambisol, Calcaric Luvisol and Dystric Gleysol; however, the height growth was more intensive on mulched soil. The height growth of the birches was modelled on the single-tree and stand levels for five soil types.     

Effect of emu oil on auricular inflammation induced with croton oil in mice

OBJECTIVE: To determine the acute anti-inflammatory effects of topically applied emu oil. ANIMALS: 96 male CD-1 mice assigned randomly to 4 groups, each comprising 24 mice. PROCEDURE: To induce auricular inflammation, 50 microl of a solution comprising 10 microl of croton oil dissolved in 1 ml of acetone was applied to the inner surface of the left auricle (pinna). One hour later, 3 or 5 microl of emu oil (low- and high-dose groups, respectively) or 5 microl of porcine oil (oil-control) was applied to the left pinna. Control mice remained untreated. Six mice per group were euthanatized 3, 6, 12, and 24 hours after induction of inflammation. Specimens of auricular tissue (ear plugs) were obtained, using a 6-mm biopsy punch. Magnitude of swelling was calculated as the weight difference between left (inflamed) and right (noninflamed) ear plugs; degree of edema was determined as the difference between wet and dry weights of the left ear plug. RESULTS: Magnitude of swelling was significantly reduced at 6 and 12 hours in mice treated with emu or porcine oil, compared with controls. The greatest reduction in swelling was detected in the high-dose emu group at 6 hours. Compared with controls, degree of edema was significantly reduced at 6 hours only in the high-dose group, whereas by 12 hours, all groups treated with oils had significantly less edema than controls. At 24 hours, magnitude of swelling and degree of edema did not differ among groups. CONCLUSION: Topically applied emu oil significantly reduced severity of acute auricular inflammation induced by croton oil in mice.     

Dysphagia as the primary clinical abnormality in two dogs with inflammatory myopathy

Two adult Boxers were evaluated because of chronic dysphagia of several years' duration. Serum creatine kinase activity was high in both dogs, but other hematologic or serum biochemical abnormalities were not detected. Esophagraphy revealed abnormalities of the cricopharyngeal phase of swallowing in both dogs, and electromyography of the pharyngeal and laryngeal muscles revealed complex repetitive discharges, positive sharp waves, and fibrillation potentials characteristic of primary myopathy or neuropathy. Because of the severity of their condition, both dogs were euthanatized. Histologically, mixed-cell infiltrates were seen in sections of the masseter and thyropharyngeal muscles. Results of indirect immunofluorescence staining for proteins associated with dystrophic myopathy were unremarkable, except for decreased staining for integrin alpha7. A diagnosis of chronic inflammatory myopathy was made. The clinical importance of reduced staining for integrin alpha7 could not be determined but was considered to be a result of the myopathy.     

Wide range of Chlamydiales types detected in native Australian mammals

The Chlamydiales are a unique order of intracellular bacterial pathogens that cause significant disease of birds and animals, including humans. The recent development of a Chlamydiales-specific 16S rDNA polymerase chain reaction (PCR) assay has enabled the identification of Chlamydiales DNA from an increasing range of hosts and environmental sources. Whereas the Australian marsupial, the koala, has previously been shown to harbour several Chlamydiales types, no other Australian marsupials have been analysed. We therefore used a 16S rDNA PCR assay combined with direct sequencing to determine the presence and genotype of Chlamydiales in five wild Australian mammals (gliders, possums, bilbies, bandicoots, potoroos). We detected eight previously observed Chlamydiales genotypes as well as 10 new Chlamydiales sequences from these five Australian mammals. In addition to PCR analysis we used antigen specific staining and in vitro culture in HEp-2 cell monolayers to confirm some of the identifications. A strong association between ocular PCR positivity and the presence of clinical disease (conjunctivitis, proliferation of the eyelid) was observed in two of the species studied, gliders and bandicoots, whereas little clinical disease was observed in the other animals studied. These findings provide further evidence that novel Chlamydiales infections occur in a wide range of hosts and that, in some of these, the chlamydial infections may contribute to clinical disease.     

Distribution of Crenosoma vulpis and Eucoleus aerophilus in the lung of free-ranging red foxes (Vulpes vulpes).

Crenosoma vulpis and Eucoleus aerophilus are nematode parasites that can cause verminous pneumonia in wild carnivores. There is a paucity of information regarding the distribution of parasites in the lungs and the relationship between histopathological and parasitological diagnoses in naturally infected foxes. The objectives of this study were: first, to study the lobar and airway distribution of C. vulpis and E. aerophilus in wild red foxes and second, to investigate the relationship between fecal and histopathological diagnoses. Samples from 6 sites of the lung and fecal contents were obtained from 51 wild foxes in Prince Edward Island. By fecal examination, 78.4% of wild foxes tested positive for C. vulpis and 68.6% for E. aerophilus. In contrast, 66.6% and 49% of foxes had histopathological evidence of C. vulpis and E. aerophilus in the lungs, respectively. Anatomically, C. vulpis was observed in the small bronchi and bronchioles of all pulmonary lobes whereas E. aerophilus was restricted to the large bronchi and the caudal lobes. Affected airways exhibited severe epithelial glandular hyperplasia and bronchiolar mucous metaplasia. It was concluded that C. vulpis is widely distributed in airways of all pulmonary lobes, whereas E. aerophilus is mainly restricted to the bronchi of caudal lobes. Also, this study showed that histological examination of lung underestimates the infection with E. aerophilus.     

Failure of neuromuscular transmission after complete nerve section in the dog.

After the ulnar nerve was surgically transected, nerve conduction velocity in the distal segment and the evoked motor unit potential (EMUP) from the interosseous muscle were recorded until neuromuscular transmission failed. In five of the six dogs in the experiment, functional conduction ceased by 4.8 days, as determined by failure of both proximal and distal stimulation of the distal segment to evoke a muscle response. From the time of section until neuromuscular failure, the nerve conduction velocity remained unchanged. The amplitude of the EMUP from the interosseous muscle, however, decreased markedly during this time. Changes in other features of the EMUP are also presented. Fibrillation (denervation) potentials did not appear until the first day that muscle response could not be detected by stimulating the nerve. These data present a principle which would enable a determination of relative extent and progression of peripheral nerve damage.     

Porcine mastitis-metritis-agalactia (MMA) syndrome: mammary gland responsiveness to oxytocin given to healthy sows during lactation

Mammary gland responsiveness to exogenous oxytocin during lactation was assessed by measuring changes in intramammary pressure of healthy sows given (IM injection) synthetic oxytocin (40 U). Response to oxytocin was measured once a week for the first 8 weeks of lactation. Recordings of pressure changes were expressed as mean area (cm2) under the trace at each 10-minute interval over 30 minutes after oxytocin had been given. During the 2nd week of lactation, there was a 55.3% increase (P less than 0.05) in responsiveness to oxytocin (25.1 +/- 4.2 cm2/10 minutes) as compared with the 1st week (13.9 +/- 2.2 cm2/10 minutes). Responsiveness decreased, however, from the 2nd to the 8th week. Since the incidence of mastitis-metritis-agalactia in sows is particularly high during the 1st week of lactation, low responsiveness of the mammary gland to oxytocin may be a contributing factor.     

Evidence from Opportunity's Microscopic Imager for water on Meridiani Planum

The Microscopic Imager on the Opportunity rover analyzed textures of soils and rocks at Meridiani Planum at a scale of 31 micrometers per pixel. The uppermost millimeter of some soils is weakly cemented, whereas other soils show little evidence of cohesion. Rock outcrops are laminated on a millimeter scale; image mosaics of cross-stratification suggest that some sediments were deposited by flowing water. Vugs in some outcrop faces are probably molds formed by dissolution of relatively soluble minerals during diagenesis. Microscopic images support the hypothesis that hematite-rich spherules observed in outcrops and soils also formed diagenetically as concretions.