Detection efficiency and habitat use to inform inventory and monitoring efforts: juvenile coho salmon in the Knik River basin,Alaska     

Suresh A. Sethi  Elizabeth Benolkin 《Ecology of Freshwater Fish》2013,22(3):398-411

Imperfect detection associated with sampling gear presents challenges for wildlife inventory and monitoring efforts. We examined occupancy dynamics and habitat use of juvenile coho salmon, Oncorhynchus kisutch, in shallow lake environments over a summer and early fall season in the Knik River area of south central Alaska using models which control for and estimate sampling gear detection efficiency. In addition, we present statements for the probability that observed absences at a survey site or from a survey area (a collection of sites) are true absences given some amount of sampling effort and analysts' beliefs about site occupancy and sampling gear detection efficiency which can be used to guide inventory and monitoring efforts for juvenile salmon or other wildlife and plant species. Occupancy modelling results demonstrate that minnow traps were effective at sampling juvenile coho in shallow lake environments, with a mean probability of detection across the study period of 0.68 (i.e., probability of detecting the presence of juvenile coho given that they are present at a trap site; SE = 0.03). Juvenile coho salmon migrated into shallow water lakes in late summer and early fall, presumably to seek out overwinter habitat. N‐mixture modelling examination of habitat use demonstrated that once in shallow lake environments, juvenile coho were widely distributed across a range of microhabitats, with some evidence for preference for shallower depths and warmer water temperatures.  相似文献   

Age-related changes in hematology and plasma chemistry values of hybrid striped bass (Morone chrysops X Morone saxatilis)     

Hrubec TC  Smith SA  Robertson JL 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2001,30(1):8-15

Hybrid striped bass (Morone chrysops X Morone saxatilis ) are an important aquaculture species yet there are few diagnostic tools available to assess their health. Hematology and clinical chemistry analyses are not used extensively in fish medicine due to the lack of reference intervals for various fish species, and because factors such as age can affect blood values. There is little published information regarding age-related changes in blood values of juvenile fish. It is important to evaluate juvenile fish, as this is the time they are raised in aquaculture settings. Determining age-related changes in the blood values of fishes would further develop clinical pathology as a diagnostic tool, enhancing both fish medicine and the aquaculture industry. The results of standard hematology and clinical chemistry analysis were evaluated in juvenile hybrid striped bass at 4, 6, 9, 15, and 19 months of age. Values for PCV and RBC indices were significantly lower, and plasma protein concentration was significantly higher in younger fish. Total WBC and lymphocyte counts were significantly higher in fish at 6 and 9 months of age, while neutrophil and monocyte counts were higher at 6, 9, and 15 months. Eosinophil counts were significantly higher in 9-month-old fish. The majority of hematologic values fell within previously established reference intervals, indicating that only slight modification to the intervals is necessary for evaluating hematologic results of hybrid striped bass at different ages. The following analytes deviated sufficiently from adult reference intervals to warrant separate reference values: plasma protein concentration at 4 months, WBC and lymphocyte counts at 15 and 19 months, and thrombocyte-like-cells at 9 months of age. Values for most biochemical analytes were significantly different among age groups except for creatinine and potassium concentrations. Comparisons with reference intervals were not made for biochemical analytes, because established reference intervals were not available. Age-related changes in hematologic and biochemical values of striped bass were similar to those reported for rainbow trout and mammals.  相似文献   

Blood chemistry values of juvenile red pacu (Piaractus brachypomus)     

Sakamoto K  Lewbart GA  Smith TM 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2001,30(2):50-52

Abstract: Blood samples were collected from 29 juvenile red pacu ( Piaractus brachypomus ), ornamental freshwater fish, to establish baseline blood chemistry values. Mean (minimum-maximum) values, obtained by automated bichromatic analysis and ion selective electrode analysis, were as follows: sodium, 150.4 (146–159) mmol/L; potassium, 3.93 (2.7–5.0) mmol/L; chloride, 138.7 (128–150) mmol/L; total CO₂, 7.5 (6–10) mmol/L; albumin, 0.86 (0.5–1.0) g/dL; lactate dehydrogenase, 237.8 (65–692) IU/L; aspartate aminotransferase, 49.1 (0–125) IU/L; creatinine, 0.31 (0.2–0.4) mg/dL; calcium, 10.80 (9.5–12.5) mg/dL; anion gap, 6.89 (1.2–12.5) mmol/L; and phosphorus, 7.29 (4.1–8.9) mg/dL.  相似文献   

Phytogeny and Cross-infectivity of Powdery Mildew Isolates (Podosphaera fuliginea s. lat.) on Cosmos and Cucumber     

Tetsuya HIRATA  Susumu TAKAMATSU 《Journal of General Plant Pathology》2001,67(1):1-6

To clarify the relationship between the phylogeny and infectivity of isolates of Podosphaera fuliginea s. lat. (= Sphaerotheca fuliginea s. lat.) from cosmos and cucumber, more than 50 powdery mildew isolates from these two plants were subjected to nucleotide sequencing or PCR-RFLP analysis of the rDNA internal transcribed spacer (ITS) region and cross-inoculation tests. The isolates from both cosmos and cucumber are genetically monotypic, and there are six nucleotide substitutions in the rDNA ITS region between isolates from cosmos and cucumber. Cross-inoculation tests of these isolates revealed that isolates from cosmos are not pathogenic on cucumber. Although isolates from cucumber produced conidia on leaves of cosmos in the laboratory, the conidial density was much lower than that from isolates from cosmos. This result, as well as the fact that the cucumber strain was not isolated from cosmos in fields, suggests that isolates from cucumber do not infect cosmos in the field. Therefore, powdery mildews on cosmos and cucumber can be regarded to have become specialized for their hosts both genetically and pathogenically. The present study reconfirms the close relationship between phylogeny and infectivity of powdery mildew fungi. Host specialization may be a trigger that causes genetic divergence of powdery mildew fungi. Received 28 June 2000/ Accepted in revised form 4 September 2000  相似文献   

Effect of pyrethroids on carbohydrate metabolic pathways in common carp,Cyprinus carpio     

K Kamalaveni  V Gopal  Ursula Sampson  D Aruna 《Pest management science》2001,57(12):1151-1154

The activity levels of succinate dehydrogenase (SDH) and glucose‐6‐phosphate dehydrogenase (G6PD) were assessed in various tissues of Cyprinus carpio var communis which had been exposed to lethal concentrations of group‐II pyrethroids (deltamethrin, cypermethrin, fenvalerate and fluvalinate) for a period of 72 h. The results indicated a steady decrease in SDH activity with a concomitant increase in G6PD activity. The decreased SDH activity indicated inhibition of SDH at mitochondrial level and the increased G6PD activity an enhancement of an alternative pathway of carbohydrate metabolism, viz the hexose monophosphate shunt (HMP) or pentose phosphate pathway as a biochemical adaptation to overcome the toxic stress. © 2001 Society of Chemical Industry  相似文献   

百倍冲水库种草养鱼防淤试验初报     

李科云  盛文亮  孙祥贵 《草业学报》1993,(3)

百倍冲水库自1976年修建以来,养鱼由于饲料长期缺乏,300亩养鱼水面常年产鲜鱼1000kg左右,库内每年淤积泥砂0.6～0.8万立方米。作者于1985～1987年在库内的消落区种植黑麦草,紫云英;荒山种象草、扁穗牛鞭草;堤坝上种岸杂一号狗牙根;幼林地种鸡脚草、拉丁鲁白三叶等牧草配套养鱼和防止水土流失进行试验研究。结果,库内年鲜鱼产量由种草前1000kg提高到7000～8000kg,泥砂淤积量每年减少0.516万立方米,经济生态效益显著。  相似文献   

清塘净对鱼类等水生生物急性致毒的研究   总被引：1，自引：0，他引：1  

何绪刚 《湖北农学院学报》1996,16(4):289-294

清塘净对鱼类等水生生物毒性强，毒力降解速度较快，是好的清塘药物。对黄鳝等水生生物９６ｈ的ＬＣ５０及安全质量浓度分别为：黄鳝２．４１ｍｇ／Ｌ和０．２４１ｍｇ／Ｌ；鲤鱼苗０．３８ｍｇ／Ｌ和０．０３８ｍｇ／Ｌ；草鱼苗０．４１ｍｇ／Ｌ和０．０４１ｍｇ／Ｌ；大型蚤０．５２ｍｇ／Ｌ和０．０５２ｍｇ／Ｌ；湖螺２．３３ｍｇ／Ｌ和０．２３３ｍｇ／Ｌ；泥鳅３．０４ｍｇ／Ｌ和０．３０４ｍｇ／Ｌ。  相似文献   

An Outbreak of Diarrhoea in One-week-old Piglets Caused by Group A Rotavirus Genotypes P[7],G3 and P[7],G5   总被引：2，自引：0，他引：2  

Barreiros MA  Alfieri AA  Alfieri AF  Médici KC  Leite JP 《Veterinary research communications》2003,27(6):505-512

Thirty-two group A isolates of rotavirus detected in faecal samples from diarrhoeic piglets, were selected for P and G genotyping using a Multiplex RT-PCR. Ten isolates, from animals less than 8 days old, characterized an outbreak of diarrhoea caused by group A rotavirus in animals. P[7],G3 (CRW8-like) and P[7],G5 (OSU-like) genotypes were detected in 5 animals each. Isolates of a group A rotavirus of genotypes compatible with the OSU prototype were those most frequently identified in single infections in older animals (20/32 strains). In addition to these, 20 isolates from piglets with diarrhoea caused by group A rotavirus, collected between May 1998 and June 1999, but not from the outbreak month, were analysed. These isolates were used to compare the types observed on the farm outside the outbreak in May 1999 and the CRW8-like genotype was found in none of these faecal samples. P[7],G5 was the most frequent genotype (10/20 strains). No outbreak of diarrhoea caused by rotavirus in 1-week-old piglets was found in any other period during the 13 months of this study.  相似文献   

A Universal `One-tube' RT-PCR Protocol for Amplifying Isolates of Bovine Viral Diarrhoea Virus     

Pfeffer M  Freyburg MV  Kaaden OR  Beer M 《Veterinary research communications》2000,24(7):491-503

The increase in the knowledge of the genetic variability of BVDV and the identification of some of the genetic determinants of its pathogenicity require robust and practical tools for rapid molecular characterization of the various genotypes of this virus. This study was undertaken to develop a standard protocol for RT-PCR that allows the amplification of various parts of the genome of BVDV without the need for optimizing each individual reaction. The reaction set-up is very flexible because it consists of two pre-mixes. These are a master mix, with all the required reagents except the desired primers, which are the components of the second pre-mix and are therefore easily interchangeable between the different reactions. After adding any primer-containing pre-mix to the fixed master mix, a non-interrupted cycling protocol led to the generation of amplicons of up to 4 kbp in size in amounts sufficient for subsequent sequencing reactions. The method was applied to five different regions of the BVDV genome: (i) the well-known 5-UTR to differentiate genotypes I and II; (ii) the entire E2 gene, or an approximately 550 bp region within the E2 gene, in order to find the molecular equivalent of antigenic varieties; (iii) the entire structural protein coding region covering the Npro, capsid, E ^RNS, E1 and E2 genes; (iv) a 2.1 kbp region embracing the NS2/3 junction which is known to be cleaved in cytopathic biotypes of BVDV; and (v) the region covering the entire NS4B and NS5A/B genes. All six RT-PCRs were successfully applied using (i) primers with lengths of between 20 and 52 nucleotides, (ii) an aliquot of RNA extracted from either 10⁶ infected bovine embryonal lung cells or the same number of leukocytes from viraemic cattle, and (iii) all the genotype I and II strains of BVDV tested. The technique described was used to generate various Sindbis virus/BVDV recombinants. The correct processing of the amplicon-derived E2 glycoprotein of BVDV strain PT810 was demonstrated by its reaction with a monoclonal antibody in an immunofluorescence assay. Given the variety of RT-PCRs tested, we conclude that this universal protocol may be useful with other RNA viruses.  相似文献   

鱼类主要内分泌激素和蛋白质代谢的关系   总被引：1，自引：0，他引：1  

王桂芹  周洪琪 《中国饲料》2007,(5):35-38

本文就鱼类主要的内分泌激素(T3、T4、GH、IGF-Ⅰ)对蛋白质代谢的调控以及饲料蛋白质质量和数量对鱼类内分泌激素分泌的调控进行概述。  相似文献