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1.
Theileria buffeli, generally a benign parasite of cattle, has been reported in animals from Texas, Missouri and North Carolina. To date, there have been no reports of the parasite in cattle residing in northern portions of the US. An 8-year-old cow (Maine Anjou x Angus cross-bred) in Michigan presented with hemoglobinuria and a packed cell volume of 9. Blood films stained with Giemsa showed numerous intraerythrocytic parasites morphologically consistent with T. buffeli. The parasite was confirmed to be T. buffeli by SSU rRNA gene sequence analysis (SSU rRNA sequence, Type A). This represents the first report of this parasite in an animal in Michigan.  相似文献   
2.
A cross-sectional, stratified random survey of Michigan dairy herds was conducted to estimate the prevalence of herds infected with Mycobacterium avium paratuberculosis (MAP), the causative agent of Johne's disease, in Michigan using targeted environmental sampling. One pooled sample each from the primary manure storage area and a high-traffic common cow area from each herd was collected and cultured for MAP using the ESP® culture system II. A herd was classified as positive if at least one sample was culture positive for MAP. State, agricultural district, and herd size stratum prevalence were calculated. Information on past MAP testing and cattle purchase history was collected, and logistic regression was performed to determine their importance to the MAP status of the herd. One hundred twenty-seven herds were contacted, and 94 agreed to participate in the study. The environment of 38 (40.4%) herds cultured positive for MAP. MAP was found in all herds (n = 15) with greater than 200 lactating cows. Herds that had tested for MAP or purchased cattle in the previous 5 years were 4.6 and 3.1 times, respectively, more likely to be infected than herds that had not. MAP continues to be prevalent on Michigan dairy farms, especially those with greater than 200 lactating cows. The environmental sampling protocol used in this study is an economically attractive alternative for monitoring herd level prevalence and the progress of Johne's disease control programs at the state or national level. Implementation of such a program would aid states in monitoring Johne's control program progress, and guide changes over time.  相似文献   
3.
Japanese stiltgrass (Microstegium vimineum), an exotic invasive plant, is native to Southeast Asia. This study was conducted to determine the chemical composition of Japanese stiltgrass as well as soil and landscape characteristics that correlate with invasion of Japanese stiltgrass around Lake Issaqueena in the upper Piedmont of South Carolina. Geographic Information Systems (GISs) and Light Detection and Ranging (LiDAR) were used to determine the spatial pattern of invasion with respect to the aspect, slope, canopy cover, soils, and distance to roads and trails. Japanese stiltgrass was distributed on both sides of Lake Issaqueena in Pacolet and Madison soil map units (Fine, kaolinitic, thermic Typic Kanhapludults) on the average slopes of 21%, but it was particularly common on the eastern shore of the lake in low-lying wet and shaded areas (mean canopy cover 51%). In addition, invasion by Japanese stiltgrass was correlated with the proximity to roads and trails. Plant tissue analysis revealed many differences in the distribution of macronutrients, macrominerals, and micronutrients in the leaves, stems, and roots of Japanese stiltgrass, although those differences were not always statistically significant. Concentrations of nitrogen (N), phosphorus (P), and calcium (Ca) were the highest in leaves while zinc (Zn) concentrations were the highest in stems and concentrations of magnesium (Mg), copper (Cu), manganese (Mn), iron (Fe), and sodium (Na) tended to be higher in roots. Carbon (C), sulfur (S), and potassium (K) concentrations were generally higher in above-ground tissues versus roots. Soil chemical analysis revealed no statistical differences between control and invaded plots. Our findings suggest that watershed areas surrounding lakes may be particularly susceptible to the invasion of Japanese stiltgrass due to their microclimates, low-lying wet pathways for seed distribution and recreational uses.  相似文献   
4.
Johne's disease (JD) is an incurable, chronic infectious disease prevalent in dairy herds throughout the US and the world. The substantial economic losses caused by JD have been well documented. However, information on the costs of controlling the disease is limited, yet necessary, if producers are to make sound decisions regarding JD management. The purpose of this paper is to describe a method for evaluating the cost-effectiveness of management changes to control JD on infected dairy farms. A 5-year longitudinal study of six dairy herds infected with JD was performed. Each herd implemented a JD control program upon study enrollment. Prevalence of JD within each herd was monitored with annual testing of all adult cows using fecal culture and/or serum ELISA. Individual cow production and culling information was collected to estimate the annual economic losses caused by JD. An economic questionnaire was developed and administered to each herd annually to estimate costs directly attributable to the JD control program. Based on the costs of the control program, and using the losses to estimate the potential benefits of the control program, the net present value (NPV) of the control program was calculated for each herd during the study and projected into the future for a total of 20 years. The NPV was calculated for four different scenarios: (1) assuming a linear decline in losses beyond the observed period of the study with JD eradication by year 20 of the control program; (2) assuming losses and JD prevalence remain constant at the rate equal to that of the last observed year while continuing the control program; (3) assuming linear increase in losses at rate equal to that in scenario 1 with no control program; and (4) assuming losses remain constant at same level as the beginning of the study with no control plan implemented. The NPV varied greatly across the herds. For scenario 1, only three herds had a positive NPV; and only two herds had a positive NPV under scenario two. In the absence of a control program, the NPV's were always negative. The costs of the JD control programs implemented on these herds averaged $30/cow/year with a median of $24/cow/year. The annual losses due to JD averaged $79/cow/year with a median of $66/cow/year. Investing in a JD control program can be cost-effective.  相似文献   
5.
The purpose of this study was to evaluate the efficacy and toxicity of a single-agent, dose-intensified doxorubicin protocol in canine hemangiosarcoma (HSA). Canine HSA is a highly malignant tumor, and most affected dogs die within 6 months of diagnosis. Doxorubicin is the most, and possibly the only, effective chemotherapeutic drug for this malignancy, but it provides only moderate improvement in survival. On the basis of previous studies reporting similar survival in dogs treated with doxorubicin as a single agent and doxorubicin-based combination chemotherapy and the concept of summation dose intensity, a dose-intensified single-agent doxorubicin protocol was initiated. Twenty dogs with HSA were recruited to participate in this study. Workup and staging were performed according to standard practice. Chemotherapy was initiated within 3 weeks of surgery. Doxorubicin was scheduled to be administered at 30 mg/m2 i.v. every 2 weeks for a total of 5 treatments. The dogs were monitored for toxicity and signs of recurrence during and at regular intervals after chemotherapy. The protocol was tolerated well. No dogs were hospitalized because of adverse effects or developed clinical signs consistent with doxorubicin-induced cardiomyopathy. There was a significant difference in survival in dogs with stage I and I1 HSA compared with dogs with stage III HSA. with median survival times of 257, 210, and 107 days, respectively. These results are slightly better than the historical control with respect to toxicity and efficacy but are not statistically different from what is achieved with standard treatments. There was no association between dose intensity and outcome.  相似文献   
6.
Human–wildlife conflict (HWC) is a significant and growing problem, with mitigation measures being increasingly dependent on sociopolitical landscapes. We surveyed 766 people from two Australian states to assess their understanding of shark attack mitigation measures. Although beach users were relatively aware of existing mitigation measures, the efficacy of aerial patrol was overestimated, as was the risk of shark attack. The latter, as well as the innate fear of shark attacks, is likely to explain the high level of worry related with shark attack and fits within the affect heuristic that can influence how people respond to risk situations. Beach users did not, however, choose beaches based on existing mitigation measures. Results highlight the need for improved education about the risks of shark attack and for further research into the emotional response from low probability–high consequences incidents.  相似文献   
7.
A 12‐month‐old male neutered mixed breed dog was presented with a history of diarrhea, lethargy, emaciation, polydypsia, and sniffling. Physical examination findings included pale mucous membranes, increased heart and respiratory rates, and normal rectal temperature (38°C). Hematologic abnormalities included anemia and thrombocytopenia. Biochemical abnormalities included hypoalbuminemia, hyperbilirubinemia, and elevated ALP and ALT activities. A SNAP 4Dx test result was positive for Ehrlichia canis. Babesia canis vogeli organisms were found in the peripheral blood films, while morulae of E canis were not seen. Real‐time polymerase chain reaction testing confirmed the presence of both B c vogeli and E canis organisms, and also was positive for Anaplasma platys infection. The dog recovered following treatment with doxycycline and imidocarb dipropionate, with normal hematology and biochemical profiles.  相似文献   
8.

Purpose

The influence of human activities on the development and functioning of urban soils and their profile characteristics is still inadequately understood. Microbial communities can change due to anthropogenic disturbances and it is unclear how they exist along urban soil profiles. This study investigates the dynamic soil properties (DSPs) and the bacterial communities along the profiles of urban soils in New York City (NYC) with varying degree of human disturbances.

Materials and methods

Eleven pedons were investigated across NYC as well as one control soil in a nearby non-urban area. Six soils are formed in naturally deposited materials (ND) and five in human-altered and human-transported materials (HAHT). For each soil, the profile was described and each horizon was sampled to assess DSPs and the bacterial community composition and diversity.

Results and discussion

The development and the DSPs of NYC soils are influenced by the incorporation of HAHT materials and atmospheric deposits. The most abundant bacterial taxa observed in the NYC soils are also present in most natural and urban soils worldwide. The bacterial diversity was lower in some soils formed in ND materials, in which the contribution of low-abundance taxa was more restricted. Some differences in bacterial community composition separated the soils formed in ND materials and in dredged sediments from the soils formed in high artifact fill and serpentinite till. Changes in bacterial community composition between soil horizons were more noticeable in urban soils formed in ND materials than in those formed in HAHT materials which display less differentiated profiles and in the non-urban highly weathered soil.

Conclusions

The bacterial diversity is not linked to the degree of disturbance of the urban soils but the variations in community composition between pedons and along soil profiles could be the result of changes in soil development and properties related to human activities and should be consistently characterized in urban soils.
  相似文献   
9.

Objective

To characterize a propofol–medetomidine-ketamine total intravenous anaesthetic in impala (Aepyceros melampus).

Study design

Prospective clinical study.

Animals

Ten adult female impala.

Materials and methods

Impala were immobilized at 1253 m above sea level with 2.0 mg thiafentanil and 2.2 mg medetomidine via projectile darts. Propofol was given to effect (0.5 mg kg?1 boluses) to allow endotracheal intubation, following which oxygen was supplemented at 2 L minute?1. Anaesthesia was maintained with a constant-rate infusion of medetomidine and ketamine at 5 μg kg?1 hour?1 and 1.5 mg kg?1 hour?1, respectively, and propofol to effect (initially 0.2 mg kg?1 minute?1) for 120 minutes. The propofol infusion was titrated according to reaction to nociceptive stimuli every 15 minutes. Cardiopulmonary parameters were monitored continuously and arterial blood gas samples were analysed intermittently. After 120 minutes' maintenance, the thiafentanil and medetomidine were antagonized using naltrexone (10:1 thiafentanil) and atipamezole (5:1 medetomidine), respectively.

Results

All impala were successfully immobilized. The median dose [interquartile range (IQR)] of propofol required for intubation was 2.7 (1.9–3.3) mg kg?1. The propofol–medetomidine–ketamine combination abolished voluntary movement and ensured anaesthesia for the 120 minute period. Propofol titration showed a generally downward trend. Median (IQR) heart rate [57 (53–61) beats minute?1], respiratory rate [10 (9–12) breaths minute?1] and mean arterial blood pressure [101 (98–106) mmHg] were well maintained. Arterial blood gas analysis indicated hypoxaemia, hyper- capnia and acidaemia. Butorphanol (0.12 mg kg?1) was an essential rescue drug to counteract thiafentanil-induced respiratory depression. All impala regurgitated frequently during the maintenance period. Recovery was calm and rapid in all animals. Median (IQR) time to standing from antagonist administration was 4.4 (3.2–5.6) minutes.

Conclusions and clinical relevance

A propofol–medetomidine–ketamine combination could provide adequate anaesthesia for invasive procedures in impala. The propofol infusion should begin at 0.2 mg kg?1 minute?1 and be titrated to clinical effect. Oxygen supplementation and airway protection with a cuffed endotracheal tube are essential.  相似文献   
10.
As scavengers, spotted hyenas (Crocuta crocuta) are exposed to a wide array of pathogens but exhibit low mortality rates due to infectious disease. This suggests that this species exhibits a unique and robust immune response to pathogens. However, few tools exist to measure cell-mediated immunity (CMI) in hyenas and we aimed to develop a gene expression assay to quantify antigen-specific responses. Whole blood from five Mycobacterium bovis- sensitised hyenas was incubated in Nil and TB antigen tubes of the QuantiFERON®-TB Gold (QFT) system. Using qPCR, the relative expression stability of the reference genes ACTB, GAPDH, YWHAZ and TBP in these samples was determined as well as the mean fold change in the expression of IFNG, CXCL8, CXCL9, CXCL10 and CXCL11 in M. bovis-antigen stimulated blood. The expression of YWHAZ and TBP showed greatest stability, and YWHAZ was selected as a reference for further analysis. The expression of CXCL9 and CXCL11 showed greatest upregulation in antigen-stimulated blood and the assay results for these genes were strongly correlated. The measurement of antigen-induced CXCL9 and CXCL11 expression, relative to that of YWHAZ, can be used to measure CMI responses to infectious diseases in spotted hyenas.  相似文献   
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