Design,Testing and Implementation of a Large-Scale Urban Dog Waste Composting Program

In Montreal, Québec, many dogs are exercised in fenced-in runs in parks. Consequently, these dog parks are a high-density source of large amounts of dog waste, which is typically collected by the owner in a plastic bag and deposited in the municipal garbage. In 2004, an experimental large-scale dog waste composting programme was initiated at the Notre-Dame-de-Grâce (NDG) dog run in Montreal, Québec. Dog waste was collected with plastic shovels, deposited into compost bins, and layered with sawdust. In two months, a total of 213kg (470 lbs) of dog waste was collected and composted, along with 33kg (72 lbs) of donated sawdust, in two research compost bins. After a year of incubation, the two bins produced 179kg (394 lbs) of compost. Temperatures in the research bins peaked between 40°C and 55°C but were not maintained long enough for conclusive elimination of pathogens. Participation by dog run users during the trial project was enthusiastic, and full-scale dog waste composting has now been implemented at the dog run, with nine bins being filled over a 12 month period. On an annual basis, this composting programme diverts almost a ton of dog waste (approximately 959kg (2,115 lbs), over 130kg (300 lbs) of sawdust, and at least 7000 plastic bags from Montreal's landfill site, and produces about 770kg (1,700 lbs) of compost annually.     

PRESUMED MINERAL OIL ASPIRATION AND CAVITARY LUNG LESIONS IN A DOG

This report describes an unusual occurrence of cavitary lung lesions which may have been secondary to aspiration of mineral oil and illustrates a possible danger of aspiration pneumonia associated with administration of lipids. Lipid pneumonia should be considered in the differential diagnosis for pulmonary disease with radiographic signs ranging from increased interstitial opacity to nodules or cavitary lung lesions. This report also emphasizes the benefits of serial radiography to detect changing pathology and the occurrence of complications such as pneumothorax.     

Differential Control of Head Blight Pathogens of Wheat by Fungicides and Consequences for Mycotoxin Contamination of Grain

Fusarium head blight of wheat is caused by a disease complex comprised of toxigenic pathogens, predominantly Fusarium spp., and a non-toxigenic pathogen Microdochium nivale, which causes symptoms visually indistinguishable from Fusarium and is often included as a causal agent of Fusarium head blight. Four field trials are reported here, including both naturally and artificially inoculated trials in which the effect of fungicide treatments were noted on colonisation by Fusarium and Microdochium, and on the production of deoxynivalenol (DON) mycotoxin. The pathogen populations were analysed with quantitative PCR and samples were tested for the presence of the mycotoxin DON. Application of fungicides to reduce Fusarium head blight gave a differential control of these fungi. Tebuconazole selectively controlled F. culmorum and F. avenaceum and reduced levels of DON, but showed little control of M. nivale. Application of azoxystrobin, however, selectively controlled M. nivale and allowed greater colonisation by toxigenic Fusarium species. This treatment also lead to increased levels of DON detected. nobreak Azoxystrobin application two days post-inoculation increased the production of DON mycotoxin per unit of pathogen in an artificially inoculated field trial. This result indicates the potential risk of increased DON contamination of grain following treatment with azoxystrobin to control head blight in susceptible wheat cultivars. This is the first study to show differential fungicidal control of mixed natural pathogen populations and artificial inoculations in field trials.     

Soil seed bank compositional change constrains biodiversity in an invaded species-rich woodland

Relationships between plant invasion and the soil seed bank in highly diverse fire adapted mediterranean woodlands are poorly understood, yet critical for that ecosystem’s conservation. Within the biodiversity hotspot of southwest Australia we investigated the composition and diversity of the Banksia woodland soil seed bank in good condition (GC), medium condition (MC) and poor condition invaded by the South African perennial species Ehrharta calycina (PCe) and Pelargonium capitatum (PCp). The investigation assessed three questions: (1) Do soil seed banks of invaded sites have fewer germinants of native species and more germinants of introduced (non-native) species than sites with minimal invasion? (2) Do soil seed banks show shifts in ecological functional types with invasion? (3) Is the soil seed bank of introduced species persistent? Native species germinants, mainly shrubs and perennial herbs, were highest in GC sites and least in poorer condition sites suggesting a reduction in their numbers had occurred over time. Introduced germinants were dominated by perennial and annual grasses, and annual herbs. E. calycina had the greatest seed density (8328 germinants m⁻²). More introduced than native germinants occurred in the litter. Rapid germination of introduced species (30% in week 1) compared to native species (4% in week 1) provides the capacity for their early dominance. A limited native soil seed bank and dominant persistent introduced soil seed bank represent great challenges for the structural and functional conservation and restoration of woodland ecosystems. This study provides key new knowledge, applicable to a wide range of ecosystems, to help formulate conservation protocols to control dominant introduced species and conserve and restore biodiverse-rich woodlands.