Metapopulation dynamics and determinants of H5N1 highly pathogenic avian influenza outbreaks in Indonesian poultry     

Farnsworth ML  Fitchett S  Hidayat MM  Lockhart C  Hamilton-West C  Brum E  Angus S  Poermadjaja B  Pinto J 《Preventive veterinary medicine》2011,102(3):206-217

In 2008, the Indonesian Government implemented a revised village-level Participatory Disease Surveillance and Response (PDSR) program to gain a better understanding of both the magnitude and spatial distribution of H5N1 highly pathogenic avian influenza (HPAI) outbreaks in backyard poultry. To date, there has been considerable collection of data, but limited publically available analysis. This study utilizes data collected by the PDSR program between April 2008 and September 2010 for Java, Bali and the Lampung Province of Sumatra. The analysis employs hierarchical Bayesian occurrence models to quantify spatial and temporal dynamics in backyard HPAI infection reports at the District level in 90 day time periods, and relates the probability of HPAI occurrence to PDSR-reported village HPAI infection status and human and poultry density. The probability of infection in a District was assumed to be dependent on the status of the District in the previous 90 day time period, and described by either a colonization probability (the probability of HPAI infection in a District given there had not been infection in the previous 90 day time period) or a persistence probability (the probability of HPAI infection being maintained in the District from the previous to current 90 day period). Results suggest that the number of surveillance activities in a district had little relationship to outbreak occurrence probabilities, but human and poultry densities were found to have non-linear relationships to outbreak occurrence probabilities. We found significant spatial dependency among neighboring districts, indicating that there are latent spatial processes that are not captured by the covariates available for this study, but which nonetheless impact outbreak dynamics. The results of this work may help improve understanding of the seasonal nature of H5N1 in poultry and the potential role of poultry density in enabling endemicity to occur, as well as to assist the Government of Indonesia target scarce resources to regions and time periods when outbreaks of HPAI in poultry are most likely to occur.  相似文献   

Effect of a Single Injection of Long-acting Progesterone on the First Ovulation in Early and Late Spring Transitional Mares     

Simon A. Staempfli  Sarah Clavier  Don L. Thompson  Patrick J. Burns  Sara K. Lyle  Angus O. McKinnon 《Journal of Equine Veterinary Science》2011,31(12):744-748

Since 1966, exogenous progestins have been used in equine practice for pregnancy maintenance, estrous suppression, and control of erratic sexual behavior. This study was designed to investigate the use of a new compounded controlled-release progesterone preparation (BioRelease P4 LA 300) in early and late spring transitional mares. In the first experiment, the pharmacodynamic properties of the preparation were studied in five geldings. In the second experiment, the use of a single intramuscular injection (600 mg) was tested in 68 embryo-recipient mares maintained under natural photoperiod in the Southern Hemisphere. Experiment 1 demonstrated elevated serum concentrations of progesterone (>1 ng/mL) for 7.6 ± 2.2 days. In experiment 2, there was no effect of treatment in mares that were treated on September 18, independent of their follicular status at day of treatment (10 to 15 mm; 20 to 25 mm, respectively). When mares with a follicular size of 20 to 25 mm were treated on October 14, significantly more progestin-treated mares (10/12; 83%) ovulated between 10 and 24 days after treatment than untreated controls (3/12; 25%) (P < .05). Additionally, there was a trend in mares treated on October 14 for a shorter treatment to ovulation interval (mean ± SD, 18.6 ± 8.7 days) compared with untreated controls (mean ± SD, 26.7 ± 14.7 days) (P = .07). Administration of one single injection of long-acting progesterone is a simple and effective method of controlling the first ovulation of the season in late transitional mares.  相似文献   

Impacts of artificial structures on the freshwater pearl mussel Margaritifera margaritifera in the River Dee,Scotland     

Susan L. Cooksley  Mark J. Brewer  David Donnelly  Luigi Spezia  Angus Tree 《水产资源保护:海洋与淡水生态系统》2012,22(3):318-330

Susceptibility to insecticides and activities of glutathione S‐transferase and esterase in populations of Lygus lineolaris (Hemiptera: Miridae) in Mississippi          下载免费PDF全文

Daniel E Fleming  Natraj Krishnan  Angus L Catchot  Fred R Musser 《Pest management science》2016,72(8):1595-1603

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The Influence of Design Parameters on Stormwater Pollutant Removal in Permeable Pavements     

Jian Huang  Caterina Valeo  Jianxun He  Angus Chu 《Water, air, and soil pollution》2016,227(9):311

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Effects of dietary molybdenum on nematode and host during Trichostrongylus vitrinus infection in lambs.     

N F Suttle  D P Knox  F Jackson  R L Coop  K W Angus 《Research in veterinary science》1992,52(2):224-229

The addition of molybdenum (0.05 mmol kg-1 dry matter) to the diet of lambs exposed for four weeks to a trickle (2500 third stage larvae per day) infection with Trichostrongylus vitrinus reduced the number and length of adult worms retrieved from the small intestine 11 days later: both effects were particularly marked in female worms from female lambs (P less than 0.01). Worms from lambs given molybdenum contained less proteinase enzyme activity and secreted less proteinases in culture irrespective of the sex of the host. Pathogenicity was not attenuated by molybdenum. Damage to the intestinal mucosa was severe in both dietary groups but infected females given molybdenum developed lower plasma albumin concentrations and lighter dressed carcases than those not given molybdenum. Neither the effects on the parasite nor those on the host could be attributed simply to molybdenum-induced copper depletion, using conventional measures of copper status. Molybdenum may be toxic to T vitrinus but may also facilitate or enhance the inflammatory process limiting larval establishment or increasing parasite rejection.  相似文献   

Persistence on cotton foliage of insecticide residues toxic to Heliothis larvae     

Angus G. L. Wilson  James M. Desmarchelier  Kim Malafant 《Pest management science》1983,14(6):623-633

Control measures for Heliothis spp. on cotton are usually applied against eggs and newly hatched larvae that infest plant terminal growth. In order to investigate the rate of degradation of a range of insecticides, leaf disc samples were collected, at intervals after application, from both fully expanded cotton leaves and unfolding terminal leaves. The samples were subjected separately to bioassay with newly hatched larvae, and to chemical analysis of the surface deposits. On old leaves, larval mortality caused by two biological insecticides declined by half after field exposure for 36 h, but for the synthetic insecticides, the interval ranged from 4.5 days with endosulfan to 18 days with fenvalerate. On new leaves, the longest interval was 7 days with fenvalerate. Chemical half-life on old leaves ranged from 1 day with endosulfan to 12 days with DDT, and was also shorter on young leaves than the equivalent biological half-life. Bioassay appears to be the most reliable method of assessing insecticidal activity over time. Dosage/mortality data were integrated to give LC₅₀ and LC₉₀ values. Leaf expansion may have the greatest effect on insecticide persistence during the 6 week period of rapid growth commencing 2 months after sowing. Expansion was slower when plants were water stressed, and accelerated following irrigation. The implications of the above findings for cotton pest management are discussed.  相似文献   

Temporal cell-mediated immune responses of cattle following experimental and natural exposure to living Brucella abortus.          下载免费PDF全文

J M Kaneene  R D Angus  D W Johnson  C C Muscoplat  R K Anderson    D E Pietz 《Canadian journal of veterinary research》1979,43(2):132-141

A study on cell-mediated immune responses in cattle with different exposure experiences to Brucella abortus was conducted by an in vitro lymphocyte stimulation assay. The purpose of this study was to determine how soon the cell-mediated immune responses would be detected following experimental exposure to B. abortus and to study the cell-mediated immune trend following experimental and natural exposure of cattle to B. abortus. The first positive cell-mediated immune responses occurred one to two weeks after experimental inoculation with living B. abortus strain 2308. The cell-mediated immune responses in these animals appeared at least one week before the appearance of of B. abortus serum agglutinating antibodies. Animals which were naturally infected with B. abortus biotypes 1 and 2 demonstrated positive cell-mediated immune responses throughout the study.  相似文献   

Breed variations in histopathologic features of chronic severe otitis externa in dogs: 80 cases (1995-2001)     

Angus JC  Lichtensteiger C  Campbell KL  Schaeffer DJ 《Journal of the American Veterinary Medical Association》2002,221(7):1000-1006

OBJECTIVE: To compare pathologic changes of the horizontal ear canal associated with chronic severe otitis externa between Cocker Spaniels and dogs of other breeds. DESIGN: Retrospective study. ANIMALS: 80 dogs with severe otitis externa that required total ear canal ablation with lateral bulla osteotomy. PROCEDURE: Medical records were reviewed for breed, sex, and age at time of surgery. Histologic specimens from the horizontal ear canal were evaluated by a single examiner for overall tissue response pattern and scored for sebaceous gland hyperplasia, ceruminous gland hyperplasia, ceruminous gland ectasia, fibrosis, pigment-laden macrophages, and osseous metaplasia. RESULTS: 48 of 80 (60%) dogs were Cocker Spaniels. Thirty-five of 48 (72.9%) Cocker Spaniels had a predominately ceruminous tissue response pattern; only 9 of 32 (28.1 %) dogs of other breeds had the same pattern. Other breeds most commonly had a pattern dominated by fibrosis (n = 13 [40.6%]); fibrosis was the predominant pattern in only 4 of 48 (8.3%) Cocker Spaniels. Discriminant analysis and K-means clustering of 4 histopathologic criteria correctly classified 75% of the dogs as Cocker Spaniels or all other breeds. CONCLUSIONS AND CLINICAL RELEVANCE: Cocker Spaniels are at increased risk for chronic severe otitis externa requiring total ear canal ablation with lateral bulla osteotomy, indicating that earlier and more aggressive management of the primary otitis externa and secondary inflammation is warranted in this breed. Cocker Spaniels with chronic severe otitis externa have distinct differences in pathologic characteristics of the horizontal ear canal, compared with other breeds.  相似文献   

Influence of flooding period and seed burial depth on Palmer amaranth (Amaranthus palmeri) seed germination     

Lucas X Franca  Darrin M Dodds  Daniel B Reynolds  Jason A Bond  Anthony Mills  Angus L Catchot  Daniel G Peterson 《Pest management science》2020,76(11):3832-3837

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