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1.
This study was performed to examine and clarify the cause of hindlimb ataxia and neuropathy seen in the South Korean horse population. Fifty horses diagnosed with hindlimb ataxia and neuropathy were referred for this study. Neurological examination was performed on 47 horses while necropsy was performed in all 50 animals. The occurrence of neurological diseases increased rapidly in the summer and 47 out of 50 horses were referred after the end of July. The incidence of neurological diseases started from the southern part of Korea in July and proceeded northward in August and September. Although there was no correlation with age, Thoroughbred and Warmblood horses showed a higher incidence rate than Halla and Jeju horses. The incidence rate was 5 times higher in geldings than in mares and stallions. Of the 20 cases, 16 were diagnosed with eosinophilic meningoencephalomyelitis in 2015. The most common lesions observed in 2016 were parasitic meningoencephalomyelitis (10 cases, 33%) and eosinophilic meningomyelitis (7 cases, 23%). Histopathological analysis of the brain and spinal cord revealed nematodes of approximately 100–200 µm in diameter, microcavitation and infiltrates of eosinophils, and brown pigmented macrophage infiltrates. The nematodes were identified as Setaria digitata via DNA sequencing, performed subsequent to polymerase chain reaction using DNA isolated from formalin-fixed paraffin-embedded tissue sections of the spinal cord. These results show that aberrant migration of Setaria digitata larva in the brain and spinal cord was a major cause for neurological signs in horses.  相似文献   
2.
The efficacy of a single intraperitoneal injection of oxolinic acid to control an outbreak of atypical Aeromonas salmonicida infection in goldsinny wrasse (Ctenolabrus rupestris) and in the treatment of systemic vibriosis in corkwing wrasse (Symphodus melops) was examined. In addition a field study was performed to examine the effect of medication on the survival rate of goldsinny wrasse in Atlantic salmon cages. Four groups of wild caught goldsinny wrasse, each of 50 fish, were treated with an intraperitoneal injection of propylene glycol:saline (50:50) (control) or 50 mg/kg oxolinic acid at a concentration of 50 mg/mL. Three days after medication the fish in all groups were treated by an intraperitoneal injection of prednisolone acetate and an increase in seawater temperature from 9.0 to 11.5 degrees C. Cumulative mortalities were 18% in the two groups treated with oxolinic acid and 94 and 100% in the unmedicated control groups, giving a 'relative percentage survival' (RPS) value of 82%. A laboratory maintained population of originally wild caught corkwing wrasse experiencing high daily mortality was treated with oxolinic acid (50 mg/kg) or propylene glycol:saline (control). Cumulative mortalities were 84% (control) and 42% (oxolinic acid medicated group) giving an RPS value of 50%. In a field investigation using goldsinny wrasse approximately 30% were medicated with oxolinic acid (50 mg/kg) prior to stocking in cages with Atlantic salmon. In two of three cages the cumulative mortality was significantly lower (P = 0.025 and P < 0.001) in the medicated groups.  相似文献   
3.
OBJECTIVE: To validate a new food-frequency questionnaire (FFQ) for measuring the intake of fruit, vegetables and tea reported by women participating in the Norwegian Mother and Child Cohort Study (MoBa). DESIGN: Intake of fruits, vegetables and tea estimated by the FFQ was compared with urinary flavonoid excretion, plasma carotenoid concentration and intake measured by a 4-day weighed food diary (FD). The triangular method was applied to calculate FFQ validity coefficients using two independent biomarkers. SETTING AND SUBJECTS: One hundred and nineteen women participating in MoBa. RESULTS: The FFQ estimate of fruit intake was significantly correlated with urine phloretin (r = 0.33), citrus fruit/juice with urine hesperetin (r = 0.44), cooked vegetables with plasma alpha-carotene (r = 0.37), and tea with urine kaempferol (r = 0.41) (P < 0.01 for all). On average, 60% of the participants fell into the same or adjacent quintiles when classified by FFQ and biomarkers. Significant correlations between the FFQ and FD were found for fruit (r = 0.39), vegetables (r = 0.34), juices (r = 0.50) and tea (r = 0.53). The FFQ validity coefficient was 0.65 for citrus fruit/juice and 0.59 for cooked vegetables as calculated by the triangular method. CONCLUSIONS: The validation study shows that the MoBa FFQ can be used to estimate fruit, juice, vegetable and tea intake in pregnant Norwegian women, and to rank individuals within the distribution.  相似文献   
4.
A rapid extraction procedure and a HPLC method for quantitative measurements of the concentration of rotenone in oysters (Ostrea edulis) and in seawater is presented. The absorption rate of rotenone by oysters was rapid. With an average rotenone concentration in the seawater of 26 ppb, the concentration in the oysters reached 4.6 ppm after 4 days of exposure. The t1/2 of the excretion of rotenone was 40 h at 10°C. The absorption rate was highly affected by both the rotenone concentration in the seawater and the seawater temperature. Rotenone was quite stable in seawater at low temperatures. At an average temperature close to 0°C, 18% of the rotenone added was still present 45 days after preparing the solution (1 ppm Gullviks rotenone mixture) in seawater. The acute mortality observed was closely related to the measured concentration of rotenone in the oysters.  相似文献   
5.
High mortality rates are often observed in rearing the early stages of the great scallop, Pecten maximus. The addition of antibacterial agents has been necessary to improve larval survival. However, as one antibacterial agent, chloramphenicol, is banned in Norway and Europe the aim of this study is to investigate alternative antibacterial agents. The therapeutic agents investigated in this study were florfenicol, oxytetracycline, oxolinic acid, neomycin and Pyceze. The mean minimum inhibitory concentration (MIC) values were determined for oxytetracycline, oxolinic acid and Pyceze against bacteria isolated from scallop larvae. Two types of treatment regime were investigated on an intermediate scale (20 L). One regime involved continuous exposure of scallop larvae to the therapeutic agent while the other involved a short exposure lasting two hours. All intermediate scale treatments were performed in parallel to large-scale production (800 L) treatment with chloramphenicol. Of the therapeutants investigated, oxolinic acid was the most effective, although only at high concentrations. The short exposure of two hours was ineffective for all therapeutics.  相似文献   
6.
In this investigation, the efficacy of a single intraperitonealinjection of either flumequine or oxytetracycline hydrochloride to preventoutbreak of atypical Aeromonas salmonicida infection ingoldsinny wrasse, Ctenolabrus rupestris, following stresswas studied. Six groups of goldsinny wrasse, each of 50 individuals, weretreated with an intraperitoneal injection of either propylene glycol : saline(50 : 50), 200 mg kg–1 of oxytetracycline or 50mg kg–1 of flumequine dissolved in propyleneglycol : saline (50 : 50). Three days following medication the fish in allgroups were stressed by an intraperitoneal injection of prednisolone acetate(0.05 ml) and a rise in seawater temperature from 9 to 11°C. Mortality was observed daily for 21 days. Flumequine wasthe more effective with a mean cumulative mortality of 5% compared tooxytetracycline with 54%. The mean cumulative mortality in the unmedicatedcontrol groups was 84%. Bacterial examination of kidneys from dead fishconfirmed the presence of atypical A. salmonicida as theprobable cause of death. Minimum inhibitory concentration (MIC) values forflumequine and oxytetracycline against the isolated A.salmonicida were determined to 0.13 gml–1, and 2.0 g ml–1,respectively.  相似文献   
7.
The duration of efficacy of emamectin benzoate in the control of Caligus curtus infestations in Atlantic cod, Gadus morhua L., was studied following an administration of 50 μg kg?1 for seven consecutive days. No lice were found on medicated fish when challenged 1 week (challenge 1) or 5 weeks (challenge 2) following termination of medication, whereas the mean abundance of lice among the unmedicated fish was 17.9 and 19.3 lice per fish in challenge 1 and 2, respectively. Muscle concentrations of 19.5 ± 8.2 ng g?1 and 3.4 ± 0.9 ng g?1, respectively, and skin concentrations of 23.1 ± 10.8 and 4.2 ± 1.0 ng g?1, respectively, were found 27 and 55 days following the termination of medication. Tissue concentrations and the duration of efficacy indicate a dosing regime for emamectin in cod, similar to the regime used for Atlantic salmon, Salmo salar L.  相似文献   
8.
The relative importance of soil bulk density, water content and potential on the self-diffusion and impedance factors of 36C1 in a sandy loam and loamy clay were studied. The soil bulk densities used represented a range of conditions from freshly tilled seedbeds to compacted soils. The volumetric water contents and pF were the main factors controlling the soil impedance factors, with bulk density making a small but significant contribution.
Soil type affects the impedance factors through differences in anion exclusion volumes, the water contents of poorly connected pores that contribute little to the diffusion process, and tortuosity of the diffusion pathways.  相似文献   
9.
Accumulating data suggest a relationship between chemerin and energy metabolism. Our group previously described gene cloning, expression analysis and the regulatory mechanism of chemerin and its own receptor in mice and cattle. The objective of the present study was to investigate the physiological effect of chemerin on endocrine changes and energy metabolism in sheep using a biologically stable chemerin analog. The chemerin analog was intravenously administrated (100 or 500 µg/head) to sheep, and plasma insulin and metabolites (glucose, nonesterified fatty acids (NEFA), triglyceride, total cholesterol and high‐density lipoprotein (HDL) cholesterol) were analyzed. The chemerin analog dramatically increased the insulin levels, and glucose levels were decreased. NEFA levels were slightly decreased at 20 min but then increased gradually from 60 to 180 min after analog administration. In addition, injection of the chemerin analog immediately increased triglyceride and total cholesterol but not HDL levels. These results suggested that chemerin analog regulated insulin secretion related to glucose metabolism and the release of triglycerides in sheep in vivo. This study provides new information about endocrine and metabolic changes in response to chemerin in sheep.  相似文献   
10.
Abstract

AIMS: The aims of this cross-sectional study were to investigate the herd and cow-level prevalence of bovine digital dermatitis (BDD) in dairy farms in the northern Taranaki region of New Zealand, and to identify whether there was any spatial clustering of herds with the disease.

METHODS: A survey of 224 dairy farms in the northern Taranaki region of New Zealand was undertaken from September 2014 to February 2015. Following training in robust criteria to confirm BDD visually, a technician inspected the rear feet of every milking cow on the farms during milking. The identity of cows with lesions and the feet involved were recorded. The proportion of cows affected among the inspected population (cow-level prevalence), the proportion of a herd affected (farm-level prevalence), and proportion of farms with ≥1 cow with lesions, were calculated. A bivariate K function analysis was then used to assess whether farms with ≥1 cow with lesions were clustered, after accounting for the distribution of the farms involved in the study.

RESULTS: Bovine digital dermatitis lesions were observed on 143/224 (63.8 (95% CI=57.5–70.1)%) farms. Within-farm prevalence was 0% on 81 (36.2%) farms, between >0 and <3% on 120 (53.5%) farms, with a maximum prevalence of 12.7% on one farm. Overall, cow-level prevalence was 707/60,455 (1.2 (95% CI=0.9–3.0)%), and on affected farms was 707/41,116 (1.7 (95% CI=1.4–2.1)%). In affected cows, 268/707 (37.9%) had a lesion on left foot only, 262/707 (37.1%) on the right foot only and 177/707 (25.0%) on both feet. The K function analysis showed no evidence of clustering of farms with BDD.

CONCLUSIONS: Bovine digital dermatitis was widespread among the survey farms, but there was no evidence that there was any clustering of herds with BDD. The cow-level prevalence on affected farms was much lower than reported elsewhere.

CLINICAL RELEVANCE: Although the prevalence at the cow level was low, if these data are representative of other regions of New Zealand, BDD could easily become a major problem on dairy farms in New Zealand, as has been observed in other countries.  相似文献   
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