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Progressive elimination of rabies in wildlife has been a general strategy in Canada and the United States; common campaign tactics are trap--vaccinate-release (TVR), point infection control (PIC), and oral rabies vaccination (ORV). TVR and PIC are labor intensive and the most expensive tactics per unit area (≈$616/km² [in 2008 Can$, converted from the reported $450/km² in 1991 Can$] and ≈$612/km² [$500/km² in 1999 Can$], respectively), but these tactics have proven crucial to elimination of raccoon rabies in Canada and to maintenance of ORV zones for preventing the spread of raccoon rabies in the United States. Economic assessments have shown that during rabies epizootics, costs of human postexposure prophylaxis, pet vaccination, public health, and animal control spike. Modeling studies, involving diverse assumptions, have shown that ORV programs can be cost-efficient and yield benefit:cost ratios >1.0. [ABSTRACT FROM AUTHOR]

Abstract: Rabies is a fatal zoonotic disease of mammals; it exacerbates the uncertainty of conserving populations of some threatened mammals (TM). Modelling affords an inexpensive, a priori way of studying key parameters of wildlife rabies transmission, rabies management economics, and TM conservation. Numerous models of rabies transmission have been published. Linear density dependent models predicted that a threshold density (K T ⩽1.0), possibly attained by culling or contraception, would eliminate an epizootic through reduced contacts among host animals. Density independent models predicted less advantage of culling and contraception in rabies control due to limited contacts among territorial host animals. Recent stochastic, mixed models offer novel predictions about the role of culling, fertility control, and oral rabies vaccination (ORV) in disease management. Use of a “threshold successful contact” rate (C T) as a parameter in these models predicts that density reduction of host animals will enhance ORV campaigns in non-TM contexts via more efficient bait delivery and vaccination. Economic analyses of medical, public health, and veterinary costs have shown post-exposure prophylaxis (PEP) and increased pet vaccinations (PV) to be major rabies-caused expenses during and after epizootics in North America. No modelling efforts have examined either the benefits-costs of rabies management strategies to conserve TM or the use of ORV, per se, to conserve TM – an omission due in part to the lack of methodologies for properly valuing TM (potential savings) and the expense or lower priority of using ORV for TM protection. This paper: (1) describes key aspects of rabies-transmission models in wildlife, (2) posits the use of C T to predict disease persistence, (3) reviews selected ORV strategies, economic studies, and benefit–cost models associated with the use of ORV as a means of rabies control in non-TM situations, (4) discusses implications of these models to the conservation of TM, and (5) recommends five steps to improve modelling of rabies transmission (wildlife disease in general), rabies-control economics, and TM conservation. [Copyright &y& Elsevier]

Abstract: A mixture of 16.47±0.038L concentrated capsicum oleoresin with 163.8±3.63L water and a total of 17.2L concentrated soybean oil with 177.1L water was dispensed over five 4.87m×4.87m plots via a grid of 128 augured holes (≈15cm-diameter×≈30cm deep) in a compacted, sandy loam soil. During the next 9 days, a total of 37 soil samples were obtained from these plots and other off-plot areas. Spectrophotometric analyses of dual aliquots of soil samples were performed to detect absorbance of capsaicin (λ max at 282nm). Analysis of variance showed that absorbance readings from points of capsicum application (augured holes) were 30-fold greater than for samples obtained 30–40cm distant (, df 1/4.22, ). Soybean-oil plot and off-plot soil samples yielded negligible absorbance readings. Thus, capsicum oleoresin persisted for ⩾10 days in this type of soil, but migration was minimal. [Copyright &y& Elsevier]

Abstract: Important nest sites for the endangered California least tern remain at the U.S. Marine Corps Base, Camp Pendleton, CA; these terns comprise approximately 17% of the state''s breeding population. This paper presents an empirical analysis of annual, fixed-cost budgets expended for reproduction-monitoring and predator-removal activities to protect this shorebird. The ex post study covered the inclusive 7-year period between 1995 and 2001. Separate regression analyses were computed using 15 biological (X B), economic (X E), and meteorological (X M) variables. In separate analyses, 14 of these variables served as independent variables to predict each of four dependent tern observation variables (i.e., Y nests, Y eggs, Y fledglings, and Y adults), with certain variables “lagged” (i.e., regressed after fixed intervals) to compensate for delayed effects of predator management. Mean net current annual reproduction-monitoring and predator-removal budgets were US$80,115 and US$78,178, respectively; annual fiscal data were converted to “proxy” variables of personnel time (h) for analysis of economic effects. Mean time spent in reproduction-monitoring (3.12 h/day) and predator-removal activities (6.96 h/day) differed greatly. Expenditures for both reproduction-monitoring and predator-removal staff hours were associated with greater counts of tern eggs and adults, with increased monitoring hours predictive of finding more tern nests and fledglings and increased predator-removal hours linked with fewer fledgling counts. No meteorological variables predicted any dependent variable. Economic issues involved in recovery of threatened and endangered species (TS/ES) are discussed. [Copyright &y& Elsevier]

Presents a study which evaluated the efficacy of chemical repellents using groups of individually-caged wild Norway rats. Damage caused by the gnawing of wild Norway rats; Methodology used; Results and discussion.

Presents a study which evaluated traditional repellents for reducing gnawing by northern pocket gophers on communications cable. Methodology of the study; Results and discussion.

Presents a study which examined the use of a flow chart of the scientific method, a technique designed to help student understand science. Reference to concerns expressed by authors over scientific illiteracy in the United States; Provisions made through the flow chart for undergraduates; Description of the scientific method; Listing of steps ascribed to the scientific method students can use to better understand this area.

3-Chloro-p-toluidine hydrochloride (CPT-HCl) is an aniline derivative used in the manufacture of the dye palatine fast yellow; it is alsoregistered as a selective, low-volume-use (<45 kg/yr) avicide. Threein vitro mutagenicity tests of CPT-HCl were performed according to methods recommended by the U.S. Environmental Protection Agency (EPA):the Ames/Salmonella assay, the Chinese hamster ovary/hypoxanthine-guaninephosphoribosyl transferase (CHO/HPRT) mammalian cell forward gene mutation assay, and the CHO chromosome aberration assay. CPT-HCl did not display mutagenic activity using the Ames/Salmonella or CHO/HPRT assays. However, CPT-HCl induced statistically significant concentration-dependent, metabolically activated increases in the proportion of aberrant cells and aberrations/cell in cultured CHO cells. Resultsare suggestive of minimal mutagenicity effects associated with exposure to anilines and their derivatives. [ABSTRACT FROM AUTHOR]

Objective: To conduct a benefit-cost analysis of the results of the domestic dog and coyote (DDC) oral rabies vaccine (ORV) program in Texas from 1995 through 2006 by use of fiscal records and relevant public health data. Design: Retrospective benefit-cost analysis. Procedures: Pertinent economic data were collected in 20 counties of south Texas affected by a DDC-variant rabies epizootic. The costs and benefits afforded by a DDC ORV program were then calculated. Costs were the total expenditures of the ORV program. Benefits were the savings associated with the number of potentially prevented human postexposure prophylaxis (PEP) treatments and animal rabies tests for the DDC-variant rabies virus in the epizootic area and an area of potential disease expansion. Results: Total estimated benefits of the program approximately ranged from $89 million to $346 million, with total program costs of $26,358,221 for the study period. The estimated savings (ie, damages avoided) from extrapolated numbers of PEP treatments and animal rabies tests yielded benefit-cost ratios that ranged from 3.38 to 13.12 for various frequencies of PEP and animal testing. Conclusions and Clinical Relevance: In Texas, the use of ORV stopped the northward spread and led to the progressive elimination of the DDC variant of rabies in coyotes (Can/s latrans). The decision to implement an ORV program was cost-efficient, although many unknowns were involved in the original decision, and key economic variables were identified for consideration in future planning of ORV programs. [ABSTRACT FROM PUBLISHER]

Progressive elimination of rabies in wildlife has been a general strategy in Canada and the United States; common campaign tactics are trap-vaccinate-release (TVR), point infection control (PIC), and oral rabies vaccination (ORV). TVR and PIC are labor intensive and the most expensive tactics per unit area (approximately $616/km(2) [in 2008 Can$, converted from the reported $450/km(2) in 1991 Can$] and approximately $612/km(2) [$500/km(2) in 1999 Can$], respectively), but these tactics have proven crucial to elimination of raccoon rabies in Canada and to maintenance of ORV zones for preventing the spread of raccoon rabies in the United States. Economic assessments have shown that during rabies epizootics, costs of human postexposure prophylaxis, pet vaccination, public health, and animal control spike. Modeling studies, involving diverse assumptions, have shown that ORV programs can be cost-efficient and yield benefit:cost ratios >1.0. [ABSTRACT FROM AUTHOR]