Live-trapping and bovine tuberculosis testing of free-ranging white-tailed deer for targeted removal

2012 ◽  
Vol 39 (2) ◽  
pp. 104 ◽  
Author(s):  
Melinda K. Cosgrove ◽  
Henry Campa ◽  
Stephen M. Schmitt ◽  
David R. Marks ◽  
Anthony S. Wilson ◽  
...  

Context Significant efforts have been made in Michigan, USA, to reduce the prevalence of bovine tuberculosis (TB) in free-ranging white-tailed deer (Odocoileus virginianus) over the past 15 years. Since 2002, however, prevalence has changed little, prompting the need for new control strategies. Aims In January–March of 2007 and 2008, a trap–test–cull project was conducted on an 11 000-ha property in the north-eastern Lower Peninsula of Michigan. The objectives were to assess the feasibility of live-trapping and testing white-tailed deer for TB as a means for targeted removal and estimate the cost of this effort. Methods Live-trapped deer were ear-tagged and a blood sample was drawn for use with the CervidTB STAT-PAK (commonly called Rapid Test) for TB diagnosis in the field. Deer testing negative were released, whereas deer testing positive were euthanised to confirm blood-test results via bacterial culture. Key results In all, 762 (741 with known sex and age) individual deer were captured and tested for TB. Adults comprised 59% (437 of 741) of the captures. Eight (1.8%) adults were positive on the blood test; six of eight (1.4% of adults) were confirmed TB positive via bacterial culture. Estimated TB prevalence in the present study was 2.5% (adjusted for Rapid Test sensitivity of 56%), being lower than what would be expected on the basis of routine hunter-harvest surveillance for this site which has yielded prevalence rates from 3.4% to 4.8%. Results demonstrated the ability to trap and test a substantial number of deer given high deer densities (16–20 deer per km2), availability of traps and abundant workers. The 2-year project cost a total of ~US$228 000, or US$38 000 per culture-positive animal. Conclusions Because of the cost and effort involved, a project such as the present one applied to Michigan’s larger TB-management area (148 018 ha) is not feasible. Implications If the efficiency and effectiveness of a trap–test–cull project could be improved by vaccinating test-negative animals, should a vaccine be approved for use in free-ranging white-tailed deer, a trap–test–cull project applied on a scale similar to the present study may prove beneficial by possibly reducing disease transmission, in addition to removing TB-positive animals.

Parasitology ◽  
2014 ◽  
Vol 141 (7) ◽  
pp. 981-987 ◽  
Author(s):  
Z. Y. X. HUANG ◽  
C. XU ◽  
F. VAN LANGEVELDE ◽  
H. H. T. PRINS ◽  
K. BEN JEBARA ◽  
...  

SUMMARYCurrent theories on disease-diversity relationships predict a strong influence of host richness on disease transmission. In addition, identity effect, caused by the occurrence of particular species, can also modify disease risk. We tested the richness effect and the identity effects of mammal species on bovine tuberculosis (bTB), based on the regional bTB outbreak data in cattle from 2005–2010 in Africa. Besides, we also tested which other factors were associated with the regional bTB persistence and recurrence in cattle. Our results suggested a dilution effect, where higher mammal species richness (MSR) was associated with reduced probabilities of bTB persistence and recurrence in interaction with cattle density. African buffalo had a positive effect on bTB recurrence and a positive interaction effect with cattle density on bTB persistence, indicating an additive positive identity effect of buffalo. The presence of greater kudu had no effect on bTB recurrence or bTB persistence. Climatic variables only act as risk factors for bTB persistence. In summary, our study identified both a dilution effect and identity effect of wildlife and showed that bTB persistence and recurrence were correlated with different sets of risk factors. These results are relevant for more effective control strategies and better targeted surveillance measures in bTB.


2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Aboma Zewude ◽  
Temesgen Mohammed ◽  
Lemma Terfassa ◽  
W. Garrett Hunt ◽  
Xueliang Pan ◽  
...  

Abstract Background Bovine tuberculosis (bTB) is prevalent in dairy cattle in Ethiopia. Currently used diagnostic tools such as the single intradermal comparative tuberculin test (SICTT) are time consuming and labor intensive. A rapid, easy-to-use and cost-effective diagnostic test would greatly contribute to the control of bTB in developing countries like Ethiopia. In the present study, two point-of-care diagnostic tests were evaluated for the detection of bTB: LIONEX® Animal TB Rapid test, a membrane-based test for the detection of antibodies to Mycobacterium bovis in blood and ALERE® Determine TB Lipoarabinomannan (LAM) Ag, an immunoassay for the detection of lipoarabinomannan (LAM) antigen (Ag) of mycobacteria in urine. A combination of the SICTT and gamma interferon (IFN-γ) test was used as the gold standard for the validation of these point-of-care tests, as it was not feasible to slaughter the study animals to carry out the historical gold standard of mycobacterial culture. A total of 175 heads of cattle having three different bTB infection categories (positive SICTT, negative SICTT, and unknown SICTT status) were used for this study. Result The sensitivity and specificity of TB LAM Ag were 72.2% (95% CI = 62.2, 80.4) and 98.8% (95% CI = 93.6, 99.7), respectively, while the sensitivity and specificity of the LIONEX Animal TB rapid test assay were 54% (95% CI = 44.1 64.3) and 98.8% (95% CI = 93.6, 99.7) respectively. The agreement between TB LAM Ag and SICTT was higher (κ = 0.85; 95% CI = 0.65–0.94) than between TB LAM Ag and IFN-γ (κ = 0.67; 95% CI = 0.52–0.81). The agreement between LIONEX Animals TB Rapid blood test and SICTT was substantial, (κ = 0.63; 95% CI = 0.49–0.77) while the agreement between LIONEX Animal TB rapid blood test and IFN-γ test was moderate (κ = 0.53; 95% CI = 0.40–0.67). Analysis of receiver operating curve (ROC) indicated that the area under the ROC curve (AUC) for TB LAM Ag was 0.85 (95% CI = 0.79–0.91) while it was 0.76 (95% CI; =0.69–0.83) for LIONEX Animal TB rapid test assay. Conclusion This study showed that TB LAM Ag had a better diagnostic performance and could potentially be used as ancillary either to SICTT or IFN-γ test for diagnosis of bTB.


Author(s):  
W.N. Reynolds

Following the 2007/08 drought, we experienced poor pasture production and persistence on our dairy farm in north Waikato, leading to decreased milksolids production and a greater reliance on bought-in feed. It is estimated that the cost of this to our farming operation was about $1300 per hectare per year in lost operating profit. While climate and black beetle were factors, they did not explain everything, and other factors were also involved. In the last 3 years we have changed our management strategies to better withstand dry summers, the catalyst for which was becoming the DairyNZ Pasture Improvement Focus Farm for the north Waikato. The major changes we made were to reduce stocking rate, actively manage pastures in summer to reduce over-grazing, and pay more attention to detail in our pasture renewal programme. To date the result has been a reduced need for pasture renewal, a lift in whole farm performance and increased profitability. Keywords: Focus farm, over-grazing, pasture management, pasture persistence, profitability


1991 ◽  
Vol 24 (10) ◽  
pp. 269-276
Author(s):  
J. R. Lawrence ◽  
N. C. D. Craig

The public has ever-rising expectations for the environmental quality of the North Sea and hence of everreducing anthropogenic inputs; by implication society must be willing to accept the cost of reduced contamination. The chemical industry accepts that it has an important part to play in meeting these expectations, but it is essential that proper scientific consideration is given to the potential transfer of contamination from one medium to another before changes are made. A strategy for North Sea protection is put forward as a set of seven principles that must govern the management decisions that are made. Some areas of uncertainty are identified as important research targets. It is concluded that although there have been many improvements over the last two decades, there is more to be done. A systematic and less emotive approach is required to continue the improvement process.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sonya Middleton ◽  
Sabine Steinbach ◽  
Michael Coad ◽  
Kevina McGill ◽  
Colm Brady ◽  
...  

AbstractTuberculin Purified Protein Derivatives (PPDs) exhibit multiple limitations: they are crude extracts from mycobacterial cultures with largely unknown active components; their production depends on culture of mycobacteria requiring expensive BCL3 production facilities; and their potency depends on the technically demanding guinea pig assay. To overcome these limitations, we developed a molecularly defined tuberculin (MDT) by adding further antigens to our prototype reagent composed of ESAT-6, CFP-10 and Rv3615c (DIVA skin test, DST). In vitro screening using PBMC from infected and uninfected cattle shortlisted four antigens from a literature-based list of 18 to formulate the MDT. These four antigens plus the previously identified Rv3020c protein, produced as recombinant proteins or overlapping synthetic peptides, were formulated together with the three DST antigens into the MDT to test cattle experimentally and naturally infected with M. bovis, uninfected cattle and MAP vaccinated calves. We demonstrated significant increases in MDT-induced skin responses compared to DST in infected animals, whilst maintaining high specificity in unvaccinated or MAP vaccinated calves. Further, MDT can also be applied in in vitro blood-based interferon-gamma release assays. Thus, MDT promises to be a robust diagnostic skin and blood test reagent overcoming some of the limitations of PPDs and warrants full validation.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Xi Huo ◽  
Jing Chen ◽  
Shigui Ruan

Abstract Background The COVID-19 outbreak in Wuhan started in December 2019 and was under control by the end of March 2020 with a total of 50,006 confirmed cases by the implementation of a series of nonpharmaceutical interventions (NPIs) including unprecedented lockdown of the city. This study analyzes the complete outbreak data from Wuhan, assesses the impact of these public health interventions, and estimates the asymptomatic, undetected and total cases for the COVID-19 outbreak in Wuhan. Methods By taking different stages of the outbreak into account, we developed a time-dependent compartmental model to describe the dynamics of disease transmission and case detection and reporting. Model coefficients were parameterized by using the reported cases and following key events and escalated control strategies. Then the model was used to calibrate the complete outbreak data by using the Monte Carlo Markov Chain (MCMC) method. Finally we used the model to estimate asymptomatic and undetected cases and approximate the overall antibody prevalence level. Results We found that the transmission rate between Jan 24 and Feb 1, 2020, was twice as large as that before the lockdown on Jan 23 and 67.6% (95% CI [0.584,0.759]) of detectable infections occurred during this period. Based on the reported estimates that around 20% of infections were asymptomatic and their transmission ability was about 70% of symptomatic ones, we estimated that there were about 14,448 asymptomatic and undetected cases (95% CI [12,364,23,254]), which yields an estimate of a total of 64,454 infected cases (95% CI [62,370,73,260]), and the overall antibody prevalence level in the population of Wuhan was 0.745% (95% CI [0.693%,0.814%]) by March 31, 2020. Conclusions We conclude that the control of the COVID-19 outbreak in Wuhan was achieved via the enforcement of a combination of multiple NPIs: the lockdown on Jan 23, the stay-at-home order on Feb 2, the massive isolation of all symptomatic individuals via newly constructed special shelter hospitals on Feb 6, and the large scale screening process on Feb 18. Our results indicate that the population in Wuhan is far away from establishing herd immunity and provide insights for other affected countries and regions in designing control strategies and planing vaccination programs.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Divine Ekwem ◽  
Thomas A. Morrison ◽  
Richard Reeve ◽  
Jessica Enright ◽  
Joram Buza ◽  
...  

AbstractIn Africa, livestock are important to local and national economies, but their productivity is constrained by infectious diseases. Comprehensive information on livestock movements and contacts is required to devise appropriate disease control strategies; yet, understanding contact risk in systems where herds mix extensively, and where different pathogens can be transmitted at different spatial and temporal scales, remains a major challenge. We deployed Global Positioning System collars on cattle in 52 herds in a traditional agropastoral system in western Serengeti, Tanzania, to understand fine-scale movements and between-herd contacts, and to identify locations of greatest interaction between herds. We examined contact across spatiotemporal scales relevant to different disease transmission scenarios. Daily cattle movements increased with herd size and rainfall. Generally, contact between herds was greatest away from households, during periods with low rainfall and in locations close to dipping points. We demonstrate how movements and contacts affect the risk of disease spread. For example, transmission risk is relatively sensitive to the survival time of different pathogens in the environment, and less sensitive to transmission distance, at least over the range of the spatiotemporal definitions of contacts that we explored. We identify times and locations of greatest disease transmission potential and that could be targeted through tailored control strategies.


Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1195
Author(s):  
Ali Saberi Derakhtenjani ◽  
Andreas K. Athienitis

This paper presents control strategies to activate energy flexibility for zones with radiant heating systems in response to changes in electricity prices. The focus is on zones with radiant floor heating systems for which the hydronic pipes are located deep in the concrete and, therefore, there is a significant thermal lag. A perimeter zone test-room equipped with a hydronic radiant floor system in an environmental chamber is used as a case study. A low order thermal network model for the perimeter zone, validated with experimental measurements, is utilized to study various control strategies in response to changes in the electrical grid price signal, including short term (nearly reactive) changes of the order of 10–15 min notice. An index is utilized to quantify the building energy flexibility with the focus on peak demand reduction for specific periods of time when the electricity prices are higher than usual. It is shown that the developed control strategies can aid greatly in enhancing the zone energy flexibility and minimizing the cost of electricity and up to 100% reduction in peak power demand and energy consumption is attained during the high-price and peak-demand periods, while maintaining acceptable comfort conditions.


1992 ◽  
Vol 17 (3) ◽  
pp. 34-37
Author(s):  
Melva J. Dwyer

Canadian publishing was inhibited from the beginning by Canada’s colonial origins and dependence on Great Britain and the USA. Few art books were published until quite recently; the relatively small, scattered population, the flooding of the market with British, American and (in Quebec) French books, and limited (at best) or non-existent sales outside Canada continue to be constraining factors. The necessity to include both English and French texts adds to the cost of book production in Canada. The publication of art books, and of exhibition catalogues, depends on the availability of government grants. Publications on the art of the North American Indian and Inuit peoples are an exception, attracting widespread interest and leading in some instances to co-publishing initiatives. In addition to the larger publishing houses, a number of small presses produce occasional art books, thanks to grants and in a few cases with the added benefit of sales abroad achieved through international networking. A government programme of support for Canadian publishing, launched in 1986, is continuing.


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