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Where to deliver baits for deworming urban red foxes for Echinococcus multilocularis control: new protocol for micro-habitat modeling of fox denning requirements.

Ikeda T, Yoshimura M, Onoyama K, Oku Y, Nonaka N, Katakura K - Parasit Vectors (2014)

Bottom Line: Improvement of the cost-benefit performance of baiting treatment is required urgently to raise and maintain the efficacy of deworming.Our denning models indicating suitable sites for delivering baits will improve the cost-benefit performance of the campaign.Our modeling protocol is suitable for the urban landscapes, and for extracting the heeding range when they select the den sites.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Parasitology, Graduate School of Veterinary Medicine, Hokkaido University, North-18, West-9, Hokkaido, Sapporo 060-0818, Japan. kitsunetsuki@hotmail.com.

ABSTRACT

Background: Deworming wild foxes by baiting with the anthelmintic praziquantel is being established as a preventive technique against environmental contamination with Echinococcus multilocularis eggs. Improvement of the cost-benefit performance of baiting treatment is required urgently to raise and maintain the efficacy of deworming. We established a spatial model of den site selection by urban red foxes, the definitive host, to specify the optimal micro-habitats for delivering baits in a new modeling approach modified for urban fox populations.

Methods: The model was established for two cities (Obihiro and Sapporo) in Hokkaido, Japan, in which a sylvatic cycle of E. multilocularis is maintained. The two cities have different degrees of urbanization. The modeling process was designed to detect the best combination of key environmental factors and spatial scale that foxes pay attention to most (here named 'heeding range') when they select den sites. All possible models were generated using logistic regression analysis, with "presence" or "absence" of fox den as the objective variable, and nine landscape categories customized for urban environments as predictor variables to detect the best subset of predictors. This procedure was conducted for each of ten sizes of concentric circles from dens and control points to detect the best circle size. Out of all models generated, the most parsimonious model was selected using Akaike's Information Criterion (AIC) inspection.

Results: Our models suggest that fox dens in Obihiro are located at the center of a circle with 500 m radius including low percentages of wide roads, narrow roads, and occupied buildings, but high percentages of green covered areas; the dens in Sapporo within 300 m radius with low percentages of wide roads, occupied buildings, but high percentages of riverbeds and green covered areas. The variation of the models suggests the necessity of accumulating models for various types of cities in order to reveal the patterns of the model.

Conclusions: Our denning models indicating suitable sites for delivering baits will improve the cost-benefit performance of the campaign. Our modeling protocol is suitable for the urban landscapes, and for extracting the heeding range when they select the den sites.

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Related in: MedlinePlus

Maps showing the landscape structures and fox den distributions in the two study areas. Panel A shows Obihiro study area and panel B shows Sapporo study area. Each study area consists of Urbanization Promoting Area (orange area) and surrounding suburban area (yellow area). Black dots in the maps indicate red fox dens.
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Fig1: Maps showing the landscape structures and fox den distributions in the two study areas. Panel A shows Obihiro study area and panel B shows Sapporo study area. Each study area consists of Urbanization Promoting Area (orange area) and surrounding suburban area (yellow area). Black dots in the maps indicate red fox dens.

Mentions: A map of the Obihiro study area is given in Figure 1-A. This study area (about 59.8 km2) consists of the whole of the Urbanization Promoting Area (UPA; about 41.9 km2) and its surrounding suburban area (about 17.9 km2). The UPA is composed of a mosaic of dwellings, commercial areas, urban parks, urban green spaces, and riverbeds. The surrounding suburban area is composed of urban parks, an area of continuous farmlands, and riverbeds of two large rivers, plus some small rivers and streams. The human population of the study area is approximately 167,000, which amounts to 96% of the total population of whole city. The population density is about 4400 people/km2.Figure 1


Where to deliver baits for deworming urban red foxes for Echinococcus multilocularis control: new protocol for micro-habitat modeling of fox denning requirements.

Ikeda T, Yoshimura M, Onoyama K, Oku Y, Nonaka N, Katakura K - Parasit Vectors (2014)

Maps showing the landscape structures and fox den distributions in the two study areas. Panel A shows Obihiro study area and panel B shows Sapporo study area. Each study area consists of Urbanization Promoting Area (orange area) and surrounding suburban area (yellow area). Black dots in the maps indicate red fox dens.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4262088&req=5

Fig1: Maps showing the landscape structures and fox den distributions in the two study areas. Panel A shows Obihiro study area and panel B shows Sapporo study area. Each study area consists of Urbanization Promoting Area (orange area) and surrounding suburban area (yellow area). Black dots in the maps indicate red fox dens.
Mentions: A map of the Obihiro study area is given in Figure 1-A. This study area (about 59.8 km2) consists of the whole of the Urbanization Promoting Area (UPA; about 41.9 km2) and its surrounding suburban area (about 17.9 km2). The UPA is composed of a mosaic of dwellings, commercial areas, urban parks, urban green spaces, and riverbeds. The surrounding suburban area is composed of urban parks, an area of continuous farmlands, and riverbeds of two large rivers, plus some small rivers and streams. The human population of the study area is approximately 167,000, which amounts to 96% of the total population of whole city. The population density is about 4400 people/km2.Figure 1

Bottom Line: Improvement of the cost-benefit performance of baiting treatment is required urgently to raise and maintain the efficacy of deworming.Our denning models indicating suitable sites for delivering baits will improve the cost-benefit performance of the campaign.Our modeling protocol is suitable for the urban landscapes, and for extracting the heeding range when they select the den sites.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Parasitology, Graduate School of Veterinary Medicine, Hokkaido University, North-18, West-9, Hokkaido, Sapporo 060-0818, Japan. kitsunetsuki@hotmail.com.

ABSTRACT

Background: Deworming wild foxes by baiting with the anthelmintic praziquantel is being established as a preventive technique against environmental contamination with Echinococcus multilocularis eggs. Improvement of the cost-benefit performance of baiting treatment is required urgently to raise and maintain the efficacy of deworming. We established a spatial model of den site selection by urban red foxes, the definitive host, to specify the optimal micro-habitats for delivering baits in a new modeling approach modified for urban fox populations.

Methods: The model was established for two cities (Obihiro and Sapporo) in Hokkaido, Japan, in which a sylvatic cycle of E. multilocularis is maintained. The two cities have different degrees of urbanization. The modeling process was designed to detect the best combination of key environmental factors and spatial scale that foxes pay attention to most (here named 'heeding range') when they select den sites. All possible models were generated using logistic regression analysis, with "presence" or "absence" of fox den as the objective variable, and nine landscape categories customized for urban environments as predictor variables to detect the best subset of predictors. This procedure was conducted for each of ten sizes of concentric circles from dens and control points to detect the best circle size. Out of all models generated, the most parsimonious model was selected using Akaike's Information Criterion (AIC) inspection.

Results: Our models suggest that fox dens in Obihiro are located at the center of a circle with 500 m radius including low percentages of wide roads, narrow roads, and occupied buildings, but high percentages of green covered areas; the dens in Sapporo within 300 m radius with low percentages of wide roads, occupied buildings, but high percentages of riverbeds and green covered areas. The variation of the models suggests the necessity of accumulating models for various types of cities in order to reveal the patterns of the model.

Conclusions: Our denning models indicating suitable sites for delivering baits will improve the cost-benefit performance of the campaign. Our modeling protocol is suitable for the urban landscapes, and for extracting the heeding range when they select the den sites.

Show MeSH
Related in: MedlinePlus