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排序方式: 共有232条查询结果,搜索用时 15 毫秒
1.
G. C. BLASIOLA JR 《Journal of fish diseases》1979,2(6):493-500
Abstract. A new species of Microsporida, Glugea heraldi , is described from the seahorse Hippocampus erectus . Measurements of fixed spores and notes on the histopathology of parasitized tissue are given. 相似文献
2.
A full ophthalmic examination was performed on 40 Siberian husky dogs using direct and indirect ophthalmoscopy, gonloscopy and nasolacrimal cannulation. Eight (20%) of the dogs were found to have distichia, 10 (25%) had excessive medial caruncular hairs, 8 (20%) had absence, displacement, or narrowing of the nasolacrimal puncta, 2 (5%) had bilateral corneal crystalline opacities, and 2 (5%) had unilateral areas of lateral corneal lipidosis. Fifty percent of the dogs had some abnormality of the iridocorneal (drainage) angle. However, in only one of these was the deformity severe enough to require glaucoma prophylaxis. An association between blue iris colour and malformation of the iridocorneal angle was noted. 相似文献
3.
Two feeding trials of 8 and 10 weeks each were conducted to quantify the dietary lysine requirement of juvenile striped bass, Morone saxatilis. Diets in both experiments contained approximately 420 g crude protein kg–1 and 13.4 MJ digestible energy (DE) kg?1. L ‐Lysine‐HCl was added to the basal diet to yield five and six treatments in the two experiments. Diets in the first experiment were determined to contain 9.2, 14.1, 14.6, 19.9 and 21.0 g available lysine kg?1 on a dry‐matter basis. Diets in the second experiment were determined to contain 14.8, 18.1, 21.3, 24.5, 27.6 and 30.9 g available lysine kg?1 on a dry‐matter basis. Weight gain, specific growth rate (SGR), feed conversion ratio (FCR), and apparent nitrogen utilization (ANU) were significantly (P < 0.05) improved by increasing dietary lysine concentrations to approximately 20 g kg?1 of diet. Least‐squares regression analysis of weight gain and SGR in the first experiment indicated a minimum dietary lysine requirement of 20.1 ± 2 g kg?1 dry diet. Least‐squares regression analysis of the same criteria measured in the second experiment yielded the following estimates of dietary lysine requirements (g kg?1 dry diet): 19.8 ± 2.3 for weight gain, 21.7 ± 1.5 for SGR, 23.7 ± 3.5 for FCR and 18.6 ± 1.3 for ANU. From these results the minimum recommended dietary lysine requirement for optimal growth of juvenile striped bass is approximately 21 g kg?1 dry diet which equates to 49 g kg?1 dietary protein or 1.57 mg kJ?1 DE. Although higher than that reported for hybrid striped bass, this requirement level is similar to those reported for many other fish species. 相似文献
4.
Organogenesis and foetal haemodynamics during the normal gestation of healthy black‐rumped agoutis (Dasyprocta prymnolopha,Wagler, 1831) bred in captivity 下载免费PDF全文
FCA Sousa GT Pessoa LS Moura JR Araújo RPS Rodrigues MAPS Barbosa AN Diniz AB Souza EG Silva LU Lucena MP Sanches OF Silva‐Filho PC Guerra JM Sousa WC Neves FR Alves 《Reproduction in domestic animals》2017,52(1):60-66
The objective of this study was to define the patterns of organogenesis and foetal haemodynamics during the normal gestation of healthy agoutis (Dasyprocta prymnolopha) kept in captivity. Thirty pregnant agoutis that ranged in size from small to medium and weighed between 2.5 and 3 kg underwent B‐mode and Doppler ultrasonography for the biometric evaluation of the foetal organs. The foetal aortic blood flow proved to be predominantly systolic, and the measured flow velocity was 78.89 ± 2.95 cm/s, with a maximum pressure gradient of 2.12 ± 0.27 mmHg. The liver was characterized by its large volume, occupying the entire cranial aspect of the abdominal cavity, and it was associated cranially with the diaphragm and caudally with the stomach. The flow velocity in the portal vein was estimated to equal 12.17 ± 2.37 cm/s, with a resistivity index of 0.82 ± 0.05. The gallbladder was centrally located and protruded cranially towards the diaphragm. The spleen was visualized as an elongated structure with tapered cranial and caudal extremities, and the foetal kidneys were visualized bilaterally in the retroperitoneal region, with the right kidney positioned slightly more cranially than the left. The morphological characterization and hemodynamic analysis of the foetal organs of black‐rumped agoutis via B‐mode and Doppler ultrasonography allow determination of the vascular network and of reference values for the blood flow required for perfusing the anatomical elements essential for maintaining the viability of foetuses at different gestational ages. 相似文献
5.
6.
Adherence, haemagglutination and cell surface characteristics of motile aeromonads virulent for fish 总被引:4,自引:0,他引:4
Abstract. Motile Aeromonas spp. virulent for fish were studied with regard to their adhesion profile. Electron microscopy demonstrated the presence of fimbriae (pili) on Aeromonas cells regardless of virulence potential. The results show no significant correlations between ability to haemagglutinate, yeast cell co-agglutination and virulence. All strains expressed mannose-sensitive haemagglutinin activity against guinea pig erythrocytes. Using four types of red blood cells no characteristic haemagglutinin pattern related to virulence could be discerned. Expression of surface haemagglutin(s) on Aeromonas hydrophila appears to be medium dependent; strains grown in liquid media demonstrated enhanced haemagglutination activity. Both virulent and avirulent strains had in vitro epithelial cell adhesive capabilities. Cell surface characteristics measured by agglutination in acriflavine and stability after boiling indicated that most virulent strains agglutinated in the presence of acriflavine, but not all sedimented after boiling. The ability of 10 selected strains of A hydrophila to grow in normal pooled catfish serum was determined. Only 17% of the virulence variations can be explained by their sensitivity to serum. 相似文献
7.
N. BHARATHAN W. R. GRAVES K. R. NARAYANAN D. J. SCHUSTER† H. H. BRYAN R. T. McMILLAN JR 《Plant pathology》1990,39(3):530-538
A disorder of unknown aetiology appearing as silvering on squash (Cucurbita pepo) leaves has become prevalent in south Florida. Typical symptoms, observed after 2 weeks of exposure to adults of Bemisia tabaci , the sweet potato whitefly (SPWF) include vein clearing followed by silvering of whole leaves. Fruits from affected plants are blanched or streaked longitudinally. The silverleaf syndrome was not mechanically transmissible when crude extracts of symptomatic leaves were used as inoculum. Two sizes of double-stranded RNA (dsRNA) of c. 4.6 and 4.2 kilobase pairs (kbp) were consistently observed in leaf extracts of caged, whitefly-infested, symptomatic plants. In contrast, caged plants not exposed to whiteflies showed no symptoms and contained no detectable dsRN A. In addition, squash plants exposed to SPWF colonies from California neither developed silverleaf symptoms nor contained any dsRNA. Double-stranded RNA could also be readily detected in whitefly-infested yellow summer squash and zucchini from the field. However, asymptomatic eggplant and watermelon infested with SPWF from nearby fields did not contain detectable dsRNA. Dot-spot hybridization assays using an RNA-specific probe detected homologous sequences in both adults and nymphs of SPWF that induced silverleaf symptoms but not in adults and nymphs of SPWF that could not induce silverleaf symptoms. These results, along with the non-endogenous nature of the detected dsRNA suggest that the dsRNA is or is associated with the causal agent of whitefly-mediated leaf silvering in squash. 相似文献
8.
TA Abdulkareem SAM Al‐Sharifi MA Ishak SM Eidan MA Alnimr CW Passavant JR Branen RG Sasser 《Reproduction in domestic animals》2011,46(3):455-462
This study was undertaken to detect pregnancy in Iraqi riverine buffalo (Bubalus bubalis) using three different methods (rectal palpation, plasma progesterone concentration and detection of the presence of pregnancy‐specific protein B (PSPB) with the BioPRYN® enzyme‐linked immunosorbent assay (ELISA) test. The aim of the study was to identify the most sensitive, early and accurate method for detecting pregnancy. Twenty‐two female riverine buffalo that were 6.0 ± 0.93 years old were used. Four blood samples per buffalo were taken via jugular venipuncture at days 22–24, 32–34, 42–44 and 58–61 post‐mating (PM) to measure the progesterone concentration (ng/ml) and to detect the presence of plasma PSPB. The rectal palpation method was employed to evaluate all buffalo on days 42–44 and 58–61 PM. The BioPRYN® test differed (p < 0.01) from the other tests with earlier accuracy for detecting pregnant and non‐pregnant buffalo. Eighty‐eight percent of pregnant and 76.9% of non‐pregnant buffalo were distinguished early (days 22–24 PM) using BioPRYN® and plasma PSPB‐ELISA level (2.09 ± 0.12 ng/ml) in relation to 66.7% and 53.9% detected using the progesterone assay at similar days (4.30 ± 0.40 ng/ml). In conclusion, these results described, for the first time, the early and accurate pregnancy detection of water riverine buffalo using BioPRYN® technology and provided the plasma levels of PSPB using an ELISA test. These findings will improve the reproductive and productive efficiency of Iraqi riverine buffalo by adapting the recent management and reproductive strategies in Iraq and in the world. 相似文献
9.
M Boller K Kelers MA Stevenson KD Winkel S Hardjo J Heller PR Judge HM Ong AM Padula C Reddrop LCP Santos CR Sharp L Smart KL Swindells D Tabrett JR Wierenga 《Australian veterinary journal》2020,98(9):442-448
SnakeMap is a national cloud-based, veterinary snakebite registry. It was designed to prospectively collect data of the clinical circumstances and temporospatial information on cases of snake envenomation in dogs and cats. We herein introduce the project and summarise the data from the first 4 years of SnakeMap. The registry is a veterinary community-based online database allowing case entry from veterinary hospitals across Australia. Registry data comprise hospital characteristics, patient characteristics, envenoming snake type, treatment and outcome variables, including time and geolocation of the snake bite. We present summative information on select key variables from the SnakeMap registry (1 July 2015 to 30 June 2019). Twenty-eight hospitals from 6 states/territories entered 624 cases into the registry, including 419 dogs (67%) and 205 cats (33%). Bite time was available in 216 animals of which 90 (42%) were reported to be bitten in the 3 hours between 03:00 pm and 05:59 pm; median bite to presentation interval was 60 (interquartile range [IQR] 30, 211) minutes in dogs and 95 (IQR 41, 238) minutes in cats. Bites occurred in the owner's yard in 356 dogs (85%) and 53 cats (26%). A snake venom detection kit was used in 172 cases (28%) and antivenom was administered in 523 cases (85%). Most animals (n = 534, 88%) survived to discharge (median hospitalisation of 25 [IQR 16, 62] hours). SnakeMap effectively collects relevant clinical data from dogs and cats with presumed snake bite and provides locally specific information on the epidemiology of snake envenomation in small animals. 相似文献
10.
Abstract Depredation can have economic, social and ecological impacts by decreasing fishery landings and threatening marine predator populations through increased risk of entanglement. This investigation quantified the loss of landings attributed to harbour seal, Phoca vitulina L., and spiny dogfish, Squalus acanthias L., depredation in the Georges Bank, Massachusetts, USA gillnet fishery. Approximately 1361 kg (2.38%) of fish was discarded from a total possible catch weight of nearly 57 300 kg because it was unsalable following depredation. Spiny dogfish accounted for 1134 kg (1.98%), and harbour seal accounted for 227 kg (0.40%) of discards. This represented an estimated US$2250 loss in profits from a total possible catch value of almost US$61 800, signifying a 3.64% market‐value loss during the assessment period. These results suggest that discarding due to harbour seal and spiny dogfish depredation results in a relatively small market loss to fishers, although additional information and research is needed before this can be confirmed. This study is the first on this subject in the fishery and provides baseline information on depredation rates that could be useful if harbour seal and spiny dogfish populations continue to increase. 相似文献