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1.
Domest Anim Endocrinol ; 79: 106707, 2022 04.
Article in English | MEDLINE | ID: mdl-35016023

ABSTRACT

When measuring blood hormones, pre-analytical sample handling can impact the quality of the results. Previous studies have shown improved stability of canine cortisol in ethylenediaminetetraacetic acid (EDTA) plasma compared to serum and interchangeability of serum and plasma when cortisol is measured by radioimmunoassay. Additionally, cortisol samples were also interchangeable when measured by chemiluminescent immunoassay if the EDTA concentration was consistent with that of optimally filled tubes, whereas excess EDTA interfered with the measurement of cortisol and serum and EDTA plasma were not interchangeable when measuring total thyroxine (TT4). The main limitation of these studies was that they were performed by spiking pooled serum samples with EDTA or in previously collected blood samples submitted to a clinical pathology laboratory. The purpose of the present study was to evaluate the effect of EDTA on the measurement of adrenocorticotropic hormone (ACTH), cortisol, TT4, free thyroxine (FT4), and thyroid stimulating hormone (TSH) in healthy dogs using the Siemens IMMULITE 1000. Whole blood from forty dogs was aliquoted into three Monoject sample tubes: no additive, completely filled EDTA tube, and 50% filled EDTA tube. Handling and storage conditions were identical, and all samples were analyzed on the same day. Bland-Altman plots and Passing-Bablok regression were used to assess agreement and risks for error, respectively. Proportional errors were found between serum and plasma samples for ACTH, cortisol, TT4, FT4, and TSH; systematic errors were also found for FT4. There was poor agreement and clinically significant differences between the measured concentrations of all hormones in serum and plasma, proving that these sample types are not interchangeable. Incompletely filled EDTA tubes were associated with significantly lower ACTH concentrations compared to completely filled EDTA tubes. When measured by chemiluminescent immunoassays that utilize alkaline phosphatase at the reporter enzyme, serum should be used for cortisol, TT4, FT4, and TSH, while plasma from completely filled EDTA tubes should be used for ACTH.


Subject(s)
Adrenocorticotropic Hormone , Hydrocortisone , Animals , Dogs , Edetic Acid , Immunoassay/methods , Immunoassay/veterinary , Thyroid Hormones , Thyrotropin , Thyroxine
2.
Res Vet Sci ; 131: 259-265, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32442726

ABSTRACT

Measuring core body temperature is used as part of the diagnostic process in assessing the health of animals. Typically in calves, this is carried out using a rectal thermometer which can be time consuming, stressful to the calf and is invasive by nature. A non-invasive technique that is gaining recognition is thermal imaging. This study investigated the use of thermal imaging as a technique to assess core body temperature in pre-weaned artificially reared calves. A total of 125 male and female calves had rectal temperatures measured daily from day 7 until day 40 of life, and at the same time had a thermal image taken of the area around the medial canthus of the eye. A weak correlation (r = 0.28) was found between calf rectal temperature and thermal image temperature. A multivariable predictive model for core body temperature increased the correlation (r = 0.32) when including the environmental parameters of air temperature (p < .001) and wind speed (p < .001) as well as reconstituted milk replacer consumption (p < .01). The effectiveness of a predictive model including these parameters for the detection of calves with a core body temperature ≥ 39.5 °C was examined and found to have a sensitivity of 0% and a specificity of 100%. The results of this study demonstrate the need to take thermal environmental parameters into consideration when using thermal imaging to assess body temperature. However, the results suggest that accurate measures of core body temperature using thermal imaging cannot be achieved under commercial farm conditions. Further research is needed to determine what other factors could be measured to increase predictive ability.


Subject(s)
Body Temperature , Cattle Diseases/diagnosis , Fever/veterinary , Animals , Cattle , Female , Fever/diagnosis , Male
3.
Vet J ; 237: 26-33, 2018 07.
Article in English | MEDLINE | ID: mdl-30089541

ABSTRACT

Lameness in dairy cattle is a persistent problem, indicating pain caused by underlying disease states and is associated with reduced milk yields. Digital dermatitis is a common cause of lameness. Thermal imaging is a technique that may facilitate early detection of this disease and has the potential for use in automated detection systems. Previous studies with thermal imaging have imaged either the heels or the coronary band of the foot and typically only used the maximum temperature (Max) value as the outcome measure. This study investigated the utility of other statistical descriptors: 90th percentile (90PCT), 95th percentile (95PCT), standard deviation (SD) and coefficient of variation (CoV) and compared the utility of imaging the heel or coronary band. Images were collected from lame and healthy cows using a high-resolution thermal camera. Analyses were done at the cow and foot level. There were significant differences between lame and healthy feet detectable at the heels (95th percentile: P<0.05; SD: P<0.05) and coronary band (SD: P<0.05). Within lame cows, 95PCT values were higher at the heel (P<0.05) and Max values were higher at the coronary band (P<0.05) in the lame foot compared to the healthy foot. ROC analysis showed an AUC value of 0.72 for Max temperature and 0.68 for 95PCT at the heels. It was concluded that maximum temperature is the most accurate measure, but other statistical descriptors of temperature can be used to detect lameness. These may be useful in certain contexts, such as where there is contamination. Differentiation of lame from healthy feet was most apparent when imaging the heels.


Subject(s)
Cattle Diseases/diagnostic imaging , Digital Dermatitis/diagnostic imaging , Lameness, Animal/diagnostic imaging , Thermography/veterinary , Animals , Cattle , Cattle Diseases/pathology , Digital Dermatitis/pathology , Female , Foot Diseases/diagnostic imaging , Foot Diseases/pathology , Foot Diseases/veterinary , Hoof and Claw/pathology , Infrared Rays , Lameness, Animal/pathology , Temperature , Thermography/methods
4.
Domest Anim Endocrinol ; 62: 60-66, 2018 01.
Article in English | MEDLINE | ID: mdl-29101821

ABSTRACT

The objective of this study was to determine the pharmacodynamics (PD) and pharmacokinetics (PK) of insulin aspart in healthy cats following intramuscular (IM) and subcutaneous (SC) injection. Eight healthy, purpose-bred cats were used in a randomized, crossover study design. Each cat had 2 isoglycemic clamps performed, one after receiving 0.25 IU/kg of insulin aspart by IM injection and one after receiving the same dose by SC injection. The two isoglycemic clamps were performed on different days, at least 48 h apart. The blood glucose, plasma endogenous insulin, and plasma insulin aspart concentrations were measured and the glucose infusion rate (GIR) was recorded during the clamp. The GIR over time was used to create a time-action curve for each clamp which was used to describe the PD of insulin aspart. Data that are normally distributed are reported as mean ± SD, while data that are not normally distributed are reported as median (25-75 percentile). When compared to the PD data that have been reported for regular insulin in healthy cats, insulin aspart had a more rapid onset (IM: 10 min [10-21.25 min], SC: 12.5 min [10-18.75 min]) and shorter duration of action (IM: 182.5 ± 34.33 min, SC: 159.38 ± 41.87 min). The onset of action (P = 0.795), time to peak action (P = 0.499), duration of action (P = 0.301), and total metabolic effect (P = 0.603) did not differ with route of administration; however, SC administration did result in a higher maximum plasma insulin aspart concentration (IM: 1,265.17 pmol/L [999.69-1,433.89 pmol/L], SC: 3,278.19 pmol/L [2,485.29-4,132.01 pmol/L], P = 0.000) and larger area under the insulin aspart vs time curve (IM: 82,662 ± 30,565 pmol/L, SC: 135,060 ± 39,026 pmol/L, P = 0.010). Insulin aspart has a rapid onset of action and short duration of effect in healthy cats when administered by IM and SC injection. Although it cannot be assumed that the PD and PK of insulin aspart will be the same in cats with diabetic ketoacidosis (DKA), our data support further investigation into the use of SC insulin aspart as an alternative to regular insulin for the treatment of DKA in cats.


Subject(s)
Glucose Clamp Technique/veterinary , Insulin Aspart/pharmacology , Insulin Aspart/pharmacokinetics , Animals , Area Under Curve , Blood Glucose , Cats , Cross-Over Studies , Female , Insulin/blood , Male , Overweight/veterinary , Weight Loss
5.
J Vet Pharmacol Ther ; 40(3): 304-308, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27586063

ABSTRACT

The aim of the study was to describe the effect of fluconazole on the pharmacokinetics of cyclosporin A in healthy dogs when investigated as a single dose and at steady-state. Five healthy adult dogs were used in the study in a crossover design receiving either 5 mg/kg of cyclosporin A (CsA) alone or 5 mg/kg of fluconazole with 2.5 mg/kg of cyclosporin A (CsA/Flu) for 35 days. Pharmacokinetic curves were performed on day 1 and day 35 in addition to sampling trough and suspected peak concentrations (C2) twice weekly with LC/MS/MS. There was no statistically significant difference noted in any pharmacokinetic value (AUC0-inf. [day 1, P = 0.225], AUCtau [day 35, P = 0.225], t½ [day 1, P = 0.279; day 35, P = 0.686], and Cmax [day 1, P = 0.225; day 35, P = 0.225]) between the treatment groups by sampling day. There was a statistically significant increase in AUC (CsA P = 0.043; CsA/Flu P = 0.043) and t½ (CsA P = 0.042, CsA/Flu P = 0.042) over time within each group. There were no significant differences in the Cmax (CsA P = 0.08; CsA/Flu P = 0.08) when comparing day 1 vs. day 35. Steady-state cyclosporine concentrations were achieved by day 10 in both groups. Subjectively, individual variability was noted among the dogs and a much larger sample size would be beneficial in a future study.


Subject(s)
Cyclosporine/pharmacokinetics , Fluconazole/pharmacology , Animals , Area Under Curve , Dogs , Immunosuppressive Agents , Tandem Mass Spectrometry
6.
Br Poult Sci ; 57(1): 134-41, 2016.
Article in English | MEDLINE | ID: mdl-26670305

ABSTRACT

An experiment was conducted to test the hypothesis that muscle damage in fast-growing broiler chickens is associated with an ambient temperature that does not permit the birds to lose metabolic heat resulting in physiological heat stress and a reduction in meat quality. The experiment was performed in 4 climate chambers and was repeated in 2 trials using a total of 200 male broiler chickens. Two treatments compared the recommended temperature profile and a cool regimen. The cool regimen was defined by a theoretical model that determined the environmental temperature that would enable heat generated by the bird to be lost to the environment. There were no differences in growth rate or feed intake between the two treatments. Breast muscles from birds on the recommended temperature regimen were lighter, less red and more yellow than those from the cool temperature regimen. There were no differences in moisture loss or shear strength but stiffness was greater in breast muscle from birds housed in the cool compared to the recommended regimen. Histopathological changes in the breast muscle were similar in both treatments and were characterised by mild to severe myofibre degeneration and necrosis with regeneration, fibrosis and adipocyte infiltration. There was no difference in plasma creatine kinase activity, a measure of muscle cell damage, between the two treatments consistent with the absence of differences in muscle pathology. It was concluded that breast muscle damage in fast-growing broiler chickens was not the result of an inability to lose metabolic heat at recommended ambient temperatures. The results suggest that muscle cell damage and breast meat quality concerns in modern broiler chickens are related to genetic selection for muscle yields and that genetic selection to address breast muscle integrity in a balanced breeding programme is imperative.


Subject(s)
Animal Husbandry/methods , Chickens/physiology , Heat-Shock Response , Hot Temperature/adverse effects , Meat/analysis , Pectoralis Muscles/physiology , Animals , Chickens/genetics , Male , Pectoralis Muscles/pathology , Random Allocation
7.
J Vet Pharmacol Ther ; 39(1): 27-31, 2016 Feb.
Article in English | MEDLINE | ID: mdl-25865750

ABSTRACT

The current available formulations of itraconazole are not ideal for dosing in cats. The capsular preparation often does not allow for accurate dosing, the oral solution is difficult to administer and poorly tolerated, and the bioavailability of compounded formulations has been shown to be poor in other species. The aim of this study was to evaluate every other day dosing of 100 mg itraconazole capsule in healthy adult cats. Ten healthy adult cats received a 100 mg capsule of itraconazole orally every 48 h for 8 weeks. Peak and trough serum concentrations of itraconazole were measured weekly using high-performance liquid chromatography (HPLC). Physical examination, complete blood count (CBC), and chemistry profiles were performed weekly. The dosage regimen achieved average therapeutic trough concentrations (>0.5 µg/mL) within 3 weeks. The protocol yielded no adverse effects in 8 of the 10 study cats, with affected cats recovering fully with discontinuation of the drug and supportive care. At 8 weeks, an average peak concentration of 1.79 ± 0.952 µg/mL (95% CI: 0.996-2.588) and an average trough concentration of 0.761 ± 0.540 µg/mL (95% CI: 0.314-1.216) were achieved. Overall, a 100 mg every other day oral dosage regimen for itraconazole in cats yielded serum concentrations with minimal fluctuation and with careful monitoring may be considered for treatment of cats with systemic fungal disease.


Subject(s)
Antifungal Agents/pharmacokinetics , Cats/blood , Itraconazole/pharmacokinetics , Animals , Antifungal Agents/administration & dosage , Antifungal Agents/blood , Drug Administration Schedule , Half-Life , Itraconazole/administration & dosage , Itraconazole/blood
8.
J Vet Intern Med ; 29(5): 1307-12, 2015.
Article in English | MEDLINE | ID: mdl-26308738

ABSTRACT

BACKGROUND: Acquired myasthenia gravis (MG) in cats most commonly causes generalized weakness without megaesophagus and is more often associated with a cranial mediastinal mass, compared to dogs. HYPOTHESIS/OBJECTIVES: To extend the clinical findings described in the report of 2000 on MG in cats (J Am Vet Med Assoc 215:55-57). ANIMALS: Two hundred and thirty-five cats with MG. METHODS: Retrospective case study to evaluate the long-term outcome and incidence of spontaneous remission in myasthenic cats. Information including signalment, clinical presentation, presence of and type of cranial mediastinal mass, treatment including surgical versus medical, survival time, and outcome including spontaneous remissions was collected and analyzed in cats diagnosed at the Comparative Neuromuscular Laboratory, University of California San Diego by detection of acetylcholine receptor antibody titers >0.3 nmol/L by immunoprecipitation radioimmunosassay. RESULTS: Acquired MG in cats is associated with a euthanasia rate of 58%. Abyssinian and Somali cats had an increased incidence of MG compared to mixed breed cats or cats of other breeds. A cranial mediastinal mass, most commonly thymoma, was observed in 52% of the cats, which is higher than in the previous report. Spontaneous remission is not a characteristic of MG in cats. CONCLUSIONS AND CLINICAL IMPORTANCE: Myasthenia gravis in cats is a chronic disease associated with a high incidence of a cranial mediastinal mass. Spontaneous remission is not common and clinicians should warn owners of the necessity for long-term treatment. The clinical outcome with a cranial mediastinal mass did not differ between surgical or medical treatment.


Subject(s)
Cat Diseases/etiology , Myasthenia Gravis/veterinary , Animals , Autoantibodies/immunology , Cat Diseases/mortality , Cat Diseases/therapy , Cats , Female , Male , Myasthenia Gravis/etiology , Myasthenia Gravis/mortality , Myasthenia Gravis/therapy , Receptors, Cholinergic/immunology , Retrospective Studies , Risk Factors , Survival Analysis , Treatment Outcome
9.
Equine Vet J ; 47(2): 160-4, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24612245

ABSTRACT

REASONS FOR PERFORMING STUDY: There is limited knowledge of the foot lesions that influence the outcome of palmar/plantar digital neurectomy (PDN). OBJECTIVES: 1) To report the short- and long-term outcomes of horses that underwent PDN to alleviate chronic foot pain due to lesions diagnosed by magnetic resonance imaging (MRI) and 2) factors that may influence the outcome of PDN. STUDY DESIGN: Multicentre retrospective study. METHODS: Medical records of 50 horses subjected to PDN due to chronic foot pain were reviewed. Age, breed, sex, athletic activity, duration of lameness, affected limb(s), response to anaesthesia of the palmar/plantar digital nerves, MRI findings and surgical technique were analysed together with follow-up data to identify factors that influenced the long-term outcomes. RESULTS: Forty-six of 50 horses (92%) responded positively to surgery; 40 (80%) were able to return to their previous athletic use for a median time of 20 months (range: 12-72 months). Eighteen (36%) horses developed post operative complications including residual lameness, painful neuromas, or early recurrence of lameness. Horses with pre-existing core or linear lesions of the deep digital flexor tendon (DDFT) had significantly shorter periods of lameness resolution after surgery than horses with dorsal border lesions of the DDFT or other foot lesions. CONCLUSIONS: Palmar/plantar digital neurectomy can improve or resolve lameness in horses with foot pain unresponsive to medical therapy without serious post operative complications. However, horses with core or linear lesions of the DDFT should not be subjected to PDN as these horses experience residual lameness or early recurrent lameness after surgery. Magnetic resonance imaging can be used to identify these horses.


Subject(s)
Foot Diseases/veterinary , Horse Diseases/surgery , Neurosurgical Procedures/veterinary , Pain/veterinary , Animals , Foot Diseases/surgery , Forelimb/surgery , Hindlimb/surgery , Horses , Pain/surgery , Retrospective Studies , Treatment Outcome
10.
Vet Comp Orthop Traumatol ; 27(6): 436-40, 2014.
Article in English | MEDLINE | ID: mdl-25328081

ABSTRACT

OBJECTIVE: To compare the ultimate tensile strength (UTS) and load to 1 and 3 mm gap formation of smooth (3-metric) and knotless barbed (4-metric) polypropylene sutures placed in a three-loop pulley pattern for canine gastrocnemius tendon repair. STUDY DESIGN: In vitro. SAMPLE SIZE: Thirty-three paired bone-tendon units with one of each pair assigned to each suture type. Barbed suture size was based on previously published materials testing results. METHODS: Each unit was placed in a servo-hydraulic testing machine and tested under single cycle tensile loading until repair failure. RESULTS: There was a significantly higher UTS for smooth polypropylene compared to the barbed polypropylene repairs. The loads resulting in 1 and 3 mm gaps for the barbed repairs were consistently significantly less than the corresponding smooth polypropylene repair values. CONCLUSION: The knotted smooth polypropylene repair was consistently stronger than the knotless barbed polypropylene repair when placed in a three-loop pulley pattern for gastrocnemius repair. CLINICAL SIGNIFICANCE: Knotless barbed polypropylene suture should not be considered equivalent to knotted smooth polypropylene of comparable tensile strength when placed in a three-loop pulley pattern for canine gastrocnemius tendon repair. The low failure loads of the barbed repair are probably due to failure of the barbs to anchor consistently throughout the tendon in the knotless configuration.


Subject(s)
Polypropylenes , Suture Techniques/veterinary , Sutures/veterinary , Tendon Injuries/veterinary , Animals , Dogs/injuries , Dogs/surgery , Suture Techniques/instrumentation , Tendon Injuries/surgery , Tensile Strength
11.
J Appl Physiol (1985) ; 116(7): 807-15, 2014 Apr 01.
Article in English | MEDLINE | ID: mdl-24408990

ABSTRACT

Ventilatory insufficiency remains the leading cause of death and late stage morbidity in Duchenne muscular dystrophy (DMD). To address critical gaps in our knowledge of the pathobiology of respiratory functional decline, we used an integrative approach to study respiratory mechanics in a translational model of DMD. In studies of individual dogs with the Golden Retriever muscular dystrophy (GRMD) mutation, we found evidence of rapidly progressive loss of ventilatory capacity in association with dramatic morphometric remodeling of the diaphragm. Within the first year of life, the mechanics of breathing at rest, and especially during pharmacological stimulation of respiratory control pathways in the carotid bodies, shift such that the primary role of the diaphragm becomes the passive elastic storage of energy transferred from abdominal wall muscles, thereby permitting the expiratory musculature to share in the generation of inspiratory pressure and flow. In the diaphragm, this physiological shift is associated with the loss of sarcomeres in series (∼ 60%) and an increase in muscle stiffness (∼ 900%) compared with those of the nondystrophic diaphragm, as studied during perfusion ex vivo. In addition to providing much needed endpoint measures for assessing the efficacy of therapeutics, we expect these findings to be a starting point for a more precise understanding of respiratory failure in DMD.


Subject(s)
Diaphragm/physiopathology , Lung/physiopathology , Muscular Dystrophy, Duchenne/physiopathology , Respiratory Mechanics , Adaptation, Physiological , Age Factors , Animals , Carotid Body/metabolism , Carotid Body/physiopathology , Collagen/metabolism , Diaphragm/innervation , Diaphragm/metabolism , Diaphragm/pathology , Disease Models, Animal , Dogs , Elasticity , Fibrosis , Lung/innervation , Muscular Dystrophy, Duchenne/genetics , Muscular Dystrophy, Duchenne/metabolism , Muscular Dystrophy, Duchenne/pathology
12.
J Vet Intern Med ; 27(4): 955-63, 2013.
Article in English | MEDLINE | ID: mdl-23734720

ABSTRACT

BACKGROUND: In dogs with appendicular osteosarcoma (OSA), increased pretreatment serum bone-specific alkaline phosphatase (BALP) activity is a negative prognostic factor, associated with shorter disease-free intervals and survival times, but a biologic basis for observed differential serum BALP activities in canine OSA patients remains incompletely defined. OBJECTIVE: Serum BALP activity will correlate with absolute tumor burden in dogs with OSA. ANIMALS: This study included 96 client-owned dogs with appendicular OSA. METHODS: In canine OSA cell lines, the expression and membranous release of BALP was evaluated in vitro. The correlation between serum BALP activity and radiographic primary tumor size was evaluated in OSA-bearing dogs. In dogs developing visceral OSA metastases, serial changes in serum BALP activities were evaluated in relation to progression of macroscopic metastases, and visceral metastatic OSA cells were evaluated for BALP expression. RESULTS: In vitro, BALP expression was not associated with either tumorigenic or metastatic phenotype, rather the quantity of membranous BALP released was proportional with cell density. In dogs devoid of macroscopic metastases, there was a positive correlation between serum BALP activity and absolute primary tumor size. In dogs with progressive OSA metastases, serum BALP activity increased and coincided with the development of macroscopic metastases. OSA cells derived from visceral metastatic lesions retained BALP expression. CONCLUSIONS AND CLINICAL IMPORTANCE: Tumor burden is a determinant of serum BALP activity in dogs with appendicular OSA. The association between increased pretreatment BALP activity and negative clinical prognosis may simply be attributed to greater initial tumor burden, and consequently more advanced tumor stage.


Subject(s)
Alkaline Phosphatase/metabolism , Bone Neoplasms/metabolism , Dog Diseases/pathology , Osteosarcoma/veterinary , Alkaline Phosphatase/genetics , Animals , Cell Line, Tumor , Dog Diseases/enzymology , Dogs , Female , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , Male , Osteosarcoma/metabolism
13.
J Comp Pathol ; 149(2-3): 356-67, 2013.
Article in English | MEDLINE | ID: mdl-23582975

ABSTRACT

Ranaviral disease has affected several species of reptiles, but disease progression and mortality in relation to environmental temperature has yet to be determined. In this study, two separate trials challenged adult female red-eared slider turtles (Trachemys scripta elegans) with a ranavirus (frog virus 3-like virus; FV3) isolate at environmental temperatures of 22 °C (n = 4) and 28 °C (n = 4). The mortality rates in the turtles in the 22 °C and 28 °C trials were 100% and 50%, respectively. Median survival time for turtles exposed to FV3 at 22 °C was 24 days, while it was 30 days in the group kept at 28 °C. Consistent microscopical lesions were observed only in the group inoculated at 22 °C and included fibrinoid necrosis of vessels in the spleen, vascular and sinusoidal thrombi in the liver, necrotizing myositis and a mild heterophilic interstitial pneumonia. Quantitative polymerase chain reaction, targeting a conserved portion of the major capsid protein, was able to detect virus copies in whole blood, oral and cloacal swabs, tongue, skeletal muscle, lung, heart, liver, spleen, ovary and kidney. Viral copy number in ante-mortem clinical samples was non-significantly highest in whole blood, while kidney had the highest viral copy number in post-mortem samples. All samples had higher virus copy number in turtles exposed to FV3 at 22 °C compared with 28 °C. This study determined that environmental temperature affects the survival and disease progression in ranavirus-infected red-eared slider turtles, which will aid in managing animals in a clinical or free-ranging setting.


Subject(s)
DNA Virus Infections/veterinary , Ranavirus/pathogenicity , Turtles/virology , Animals , Temperature , Virulence
16.
J Vector Ecol ; 36 Suppl 1: S132-7, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21366765

ABSTRACT

In laboratory studies, insecticides (diflubenzuron, novaluron, methoprene and, pyriproxyfen) that have been incorporated into rodent diets were effective as feed-throughs against sand fly larvae. Novaluron also was effective against sand fly larvae at low concentrations and under simulated field conditions. Ivermectin has been shown to be effective as a systemic insecticide, killing 100% of blood-feeding sand flies for up to seven d after rodents were treated. The fluorescent tracer technique (FTT) is the use of certain fluorescent dyes (rhodamine B or uranine O) as feed-through transtadial biomarkers for phlebotomine sand flies, systemic biomarkers for blood-feeding sand flies, and permanent markers for nectar-feeding sand flies. The results of these laboratory studies provide proof of concept for the FTT and indicate that the FTT could be used to delineate specific foci with rodent/sand fly associations that would be susceptible to control by using feed-through or systemic insecticides, or foci where insecticide-treated sugar baits could be used against sand flies.


Subject(s)
Insect Control/methods , Insecticides/pharmacology , Mesocricetus/parasitology , Phlebotomus/drug effects , Animals , Cricetinae , Insecticides/administration & dosage , Phlebotomus/growth & development
17.
IEEE Trans Vis Comput Graph ; 17(4): 440-53, 2011 Apr.
Article in English | MEDLINE | ID: mdl-20498509

ABSTRACT

Current visual analytics systems provide users with the means to explore trends in their data. Linked views and interactive displays provide insight into correlations among people, events, and places in space and time. Analysts search for events of interest through statistical tools linked to visual displays, drill down into the data, and form hypotheses based upon the available information. However, current systems stop short of predicting events. In spatiotemporal data, analysts are searching for regions of space and time with unusually high incidences of events (hotspots). In the cases where hotspots are found, analysts would like to predict how these regions may grow in order to plan resource allocation and preventative measures. Furthermore, analysts would also like to predict where future hotspots may occur. To facilitate such forecasting, we have created a predictive visual analytics toolkit that provides analysts with linked spatiotemporal and statistical analytic views. Our system models spatiotemporal events through the combination of kernel density estimation for event distribution and seasonal trend decomposition by loess smoothing for temporal predictions. We provide analysts with estimates of error in our modeling, along with spatial and temporal alerts to indicate the occurrence of statistically significant hotspots. Spatial data are distributed based on a modeling of previous event locations, thereby maintaining a temporal coherence with past events. Such tools allow analysts to perform real-time hypothesis testing, plan intervention strategies, and allocate resources to correspond to perceived threats.

18.
Med Vet Entomol ; 25(2): 227-31, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21073493

ABSTRACT

The juvenile hormone analogues methoprene and pyriproxyfen were evaluated as rodent feed-through insecticides for control of immature stages of the sandfly Phlebotomus papatasi Scopoli (Diptera: Psychodidae). The development and survival of P. papatasi second-instar larvae fed faeces from Syrian hamsters, Mesocricetus auratus, that had been fed a diet containing methoprene (0, 9.788, 97.88 or 978.8 p.p.m.) or pyriproxyfen (0, 9.82, 98.2 or 982 p.p.m.) were evaluated. The faeces of methoprene-treated hamsters greatly reduced the percentage of larvae that pupated at all concentrations tested and prevented adult emergence at all but the lowest concentration (9.788 p.p.m.). Pyriproxyfen prevented both pupation and adult emergence at all concentrations tested. The results of this study suggest that a control strategy using rodent baits containing juvenile hormone analogues to control phlebotomine sandflies that live in rodent burrows and feed on rodent faeces may be possible. As rodent reservoirs and vectors of Leishmania major live in close association in many parts of the Middle East, control of the transmission of the agent of zoonotic cutaneous leishmaniasis may also be possible.


Subject(s)
Insect Control/methods , Insecticides/pharmacology , Methoprene/pharmacology , Phlebotomus/drug effects , Pyridines/pharmacology , Animals , Cricetinae , Feces/chemistry , Juvenile Hormones/administration & dosage , Juvenile Hormones/toxicity , Larva/drug effects , Larva/growth & development , Leishmaniasis, Cutaneous/prevention & control , Mesocricetus/metabolism , Phlebotomus/growth & development
19.
J Am Mosq Control Assoc ; 24(2): 323-6, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18666544

ABSTRACT

Ivermectin was evaluated as a potential rodent feed-through for the control of immature stages of Phlebotomus papatasi. The survival of sand fly larvae fed feces of Syrian hamsters (Mesocricetus auratus) that had been fed a diet containing 0, 2, 6, 10, 20, 60, or 100 ppm ivermectin was measured. Sand fly larvae fed the feces of ivermectin-treated hamsters had significantly reduced survival, with 100% mortality of larvae fed feces of hamsters fed a diet containing 20, 60, and 100 ppm ivermectin. The results of this study suggest that a control strategy using rodent baits containing ivermectin to control phlebotomine sand flies may be possible. Because rodent reservoirs and sand fly vectors of Leishmania major live in close association in many parts of the Middle East, the control of transmission of the agent of zoonotic cutaneous leishmaniasis also may be possible.


Subject(s)
Insect Control/methods , Insecticides/administration & dosage , Ivermectin/administration & dosage , Mesocricetus , Phlebotomus , Animals , Cricetinae , Feces , Larva
20.
Vet Pathol ; 45(3): 401-8, 2008 May.
Article in English | MEDLINE | ID: mdl-18487502

ABSTRACT

Histologic findings are described for 408 feather-picking or self-mutilating psittacines with the use of biopsies from clinically affected and unaffected skin. Inflammatory skin disease was diagnosed in 210 birds, and traumatic skin disease was diagnosed in 198 birds. Criteria used for the diagnosis of inflammatory skin disease included the presence of perivascular inflammation in the superficial or deep dermis of clinically affected and unaffected sites. The primary histologic criteria for the diagnosis of traumatic skin disease were superficial dermal scarring with or without inflammation in the affected sites and an absence of inflammation in the unaffected sites. The inflammatory cells associated with the lesions were typically lymphocytes and occasionally plasma cells, histiocytes, and granulocytes. A preponderance of inflammatory skin disease was seen in macaws (Ara spp.) and Amazon parrots (Amazona spp.). A preponderance of traumatic skin disease was seen in cockatoos (Cacatua spp.) and African grey parrots (Psittacus erithacus). The prevalence of each was approximately equal in several other species, including conures (Aratinga and Pyrrhura spp.), eclectus parrots (Eclectus roratus), quaker parrots (Myiopsitta monachus), cockatiels (Nymphicus hollandicus), parakeets (Cyanorhamphus and Psittacula spp.), and caiques (Pionites spp.). No geographic or gender-based trends were identified. These findings could be helpful for identifying and treating birds with feather-picking disorders.


Subject(s)
Aggression , Behavior, Animal , Bird Diseases/pathology , Feathers , Parrots/physiology , Skin Diseases/veterinary , Animals , Dermatitis/etiology , Dermatitis/pathology , Dermatitis/veterinary , Skin Diseases/pathology , Species Specificity
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