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1.
ABSTRACT: An application of the acoustic Doppler current profiler (ADCP, 153.6 kHz) in combination with a scientific echo sounder (EK60, 38 and 200 kHz) was investigated to estimate the density of krill Euphausia pacifica . The acoustic backscattering strength from sound scattering layers was compared with biomass estimates from midwater trawls. Euphausia pacifica was targeted among mixed species populations in the sound scattering layer in the offshore Funka Bay area of Hokkaido, Japan. The frequency characteristics of acoustic backscattering by krill were calculated using a distorted wave Born approximation scattering model at three frequencies. Krill aggregations identified from the EK60 data were extracted as the mean volume backscattering strength difference between two frequencies. They were then used to identify similar aggregations in the ADCP data by matching observation times and depths for the two methods, which were applied simultaneously. Results from the comparison of the mean volume backscattering strength and the density calculated from the ADCP and EK60 showed that ADCP can be used to measure density and spatial–temporal distribution of krill aggregations. Current speed and direction at the study site were found to be 16.1 cm/s and 187.0°, respectively, and krill speed and direction (including the current component) were found to be 19.8 cm/s and 172.2°, respectively. Based on the ADCP data, the net speed and direction of the krill aggregations were found to be 5.9 cm/s and 128.0°, respectively. 相似文献
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Jiyoung PARK Aryung NAM Hae-Beom LEE Seong Mok JEONG Dae-Hyun KIM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(6):799
A 10-year-old intact male Shih Tzu dog presented with hematuria. Double-contrast cystography revealed a polypoid filling defect at the apex of the urinary bladder. Ultrasonography revealed a heterogeneously hypoechoic intramural mass with minimal vascular flow beneath the submucosal layer. After partial cystectomy, a well-demarcated bladder leiomyosarcoma was diagnosed on histopathology. The patient was alive and well without any clinical signs, recurrence, or metastasis at the 29-month follow-up after the surgical removal of the bladder mass. Leiomyosarcoma should be considered as a differential diagnosis if mass-like lesions are observed in the urinary bladder, although this type of malignancy is rare in canines. Histopathological confirmation is important for predicting prognosis and determining further medical plans. 相似文献
4.
Soo-Young CHOI Woo-Chang JEONG Young-Won LEE Ho-Jung CHOI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):239-244
Contrast enhanced ultrasound (CEUS) is useful to evaluate tissue perfusion in the kidney. In veterinary
medicine, sedation or anesthesia may be required in uncooperative or panting patients. The aim of this study
was to evaluate and compare the normal kidney perfusion patterns in conscious and anesthetized dogs using
CEUS. Eight healthy beagles were used in this study. Scanning was performed in conscious dogs using manual
restraint (conscious group), or under general anesthesia using tiletamine-zolazepam and medetomidine (TZM
group) or medetomidine (M group). The contrast agent (Sonovue®) was administered as an IV bolus.
The peak intensity (PI), time to peak enhancement from injection (TTP0) and the time to peak
enhancement from the initial rise (TTPup), upslope, downslope and area under the curve (AUC) were
analyzed. Compared to the cortical values in the conscious group, TTP0 was significantly delayed in
the TZM group, and upslope, TTP0 and TTPup were significantly different in the M group.
The AUCs in the TZM and M groups were not different from those in the conscious group. The upslope of renal
medullary perfusion was significantly decreased in the TZM and M groups. TTP0 and TTPup
were also significantly delayed in these groups. The AUC of the medulla was significantly decreased in the M
group. Therefore, TZM is useful as an anesthetic protocol when performing CEUS, and the obtained data may
serve as reference values in the evaluation of renal perfusion using CEUS in dogs under anesthesia. 相似文献
5.
Hyunkyoung LEE Hyeshin HWANG Younghye RO Ji-Hyeon KIM Kyunghyun LEE Eunjin CHOI Youchan BAE Byungjae SO Inhyung LEE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(5):869
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
6.
Ahram KIM Naoki SASAKI Inhyung LEE Jong-pil SEO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):643
The purpose of this study was to assess the cardiorespiratory and behavioral responses to the combination of medetomidine and tramadol (M-T) or butorphanol (M-B) in standing laparoscopic ovariectomy in horses. One ovary was removed under M-T and the contralateral ovary was removed under M-B with at least 4 weeks between operations at random. Horses were sedated using intravenous medetomidine (5 µg/kg) followed by tramadol (1 mg/kg) or butorphanol (10 µg/kg) after 5 min. Sedation was maintained through the repeated injection of medetomidine (1 µg/kg) and tramadol (0.4 mg/kg) or medetomidine (1 µg/kg) and butorphanol (4 µg/kg) every 15 min. Cardiorespiratory function and behavioral responses, including, sedation, ataxia, and analgesia, were assessed during the surgery. There were no significant differences in cardiorespiratory values and sedation and analgesia scores between M-T and M-B. Ataxia scores were significantly lower in M-T than in M-B. This result suggests that M-T could maintain smooth and stable standing surgery with minimal cardiorespiratory changes in horses. 相似文献
7.
Hyeryoung JEONG Hanbin LEE Jaihyun JUNG Hyunryung KIM Jin YU Hyounglok YOON Youngjae LEE Jinhwa CHANG Dongwoo CHANG 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):581
Unlike echocardiography, cardiac magnetic resonance imaging (cardiac MRI) results in a near-exact assessment of cardiac structures and function. However, most veterinary studies have focused on dogs with normal cardiac function. We hypothesized that there would be significant differences in cardiac measurements between cardiac MRI and echocardiography when left ventricular (LV) function was abnormal. This study was undertaken to compare measurements of LV function produced by cardiac MRI and echocardiography in dogs whose LV function was altered by pharmacological agents. This study was conducted with six healthy beagle dogs. We increased left ventricular contractility by administration of dobutamine; we decreased cardiac contractility with esmolol. Stroke volume measurements were made by using both cardiac MRI and echocardiography under seven different conditions with general anesthesia: control, three doses of esmolol (100, 200, and 500 µg/kg/min), and three doses of dobutamine (10, 20, and 50 µg/kg/min). Experiments involving each condition were conducted at least 1 week apart. When LV contractility was normal, ejection fraction (EF) and stroke volume (SV), as measured by echocardiography and cardiac MRI, were not significantly different. However, when contractility was changed by pharmacological agents, EF and SV were overestimated by echocardiography, compared to MRI. Evaluation of cardiac function in patients treated with pharmacological agents should be conducted carefully because EF and SV measured by echocardiography can be overestimated, compared with EF and SV obtained by cardiac MRI. 相似文献
8.
In trace metal (TM)-contaminated agricultural soils, management of TM availability is important for safe crop production. In addition, maintenance or improvement of soil quality is vital for sustainable crop cultivation. Decreased TM phytoavailability and increased soil quality can be achieved by the application of various immobilizing agents to soil, which can supply both macronutrients and organic matter. This study investigated the long-term influences of four common immobilizing agents on so... 相似文献
9.
A long‐term feeding experiment was conducted to investigate the use of cottonseed and soybean meal (CS) with iron and phosphorus supplements in diets for olive flounder (Paralichthys olivaceus). Olive flounder with an initial average size of 28.5 ± 0.35 g (mean ± SD) were divided into 15 groups (three tanks per dietary treatment) and fed 480 g kg?1 crude protein diets in which each of five isonitrogenous diets was formulated to contain different levels of cottonseed/soybean meal (1 : 1) to replace fish meal (FM) with iron and phosphorus supplementations. The five experimental diets were as follows: diet 1 (control), 0%CS; diet 2, 20%CS; diet 3, 30%CS; diet 4, 30%CS + Fe&P; and diet 5, 40%CS + Fe&P. After 26 weeks of feeding trial, no significant differences were observed in weight gain, feed utilization and survival among all the treatments. The total gossypol accumulation in liver of fish fed diets supplemented with iron was significantly lower than that of fish fed diets without supplementation of iron. The results indicate that the addition of iron in diets could prevent the absorption of free gossypol. The findings in this study suggest that dietary supplements of iron and phosphorus could increase the inclusion of cottonseed and soybean meal for FM replacement in diets for marine fish species. 相似文献
10.
M. A. PARK S. G. SOHN S. D. LEE S. K. CHUN J. W. PARK J. L. FRYER Y. C. HAH 《Journal of fish diseases》1993,16(5):471-478
Abstract. Four isolates of infectious haematopoietic necrosis virus (IHNV) were obtained from rainbow trout, Oncorhynchus mykiss (Walbaum), and masu salmon, Oncorhynchus masou (Walbaum), fry during epizootics at hatcheries in Korea. The four isolates of IHNV were compared with three from salmonids in the USA (SRCV, OSV and RB-76) by analysis of virion proteins in sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and neutralization tests, with two monoclonal antibodies raised against SRCV (MAb SRCV/A4) and RB-76 (MAb RB/B5). Based on the antigenicity and the size of the structural proteins, one Korean isolate from masu salmon (SCS) is similar to RB-76 and is an electropherotype 1. The other three isolates from rainbow trout (PRT, YRT and MRT) were identical to each other in the mobilities of their virion proteins in SDS-PAGE, and although their nucleocapsid (N) proteins comigrated with that of the RB-76 isolate, they differed from RB-76 in the smaller matrix 2 (M2) protein they contained. In addition, the three Korean isolates (PRT, YRT and MRT) could be divided into two groups by reactivity with MAb RB/B5. While the YRT isolate was neutralized by this MAb, the PRT and MRT isolates were not, suggesting that there are at least two neutralizing antigenic variants of IHNV in Korea. 相似文献