scholarly journals Evaluation of Two Formalin Concentrations During Yellow Perch Egg Incubation

2019 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Matthew J. Ward ◽  
Michael E. Barnes

Daily 15-minute treatments of formalin at 1667 mg/L are typically used to prevent water mold infestations in coolwater fish eggs. This study evaluated the use of a reduced concentration of 834 mg/L during yellow perch Perca flavescens egg incubation until the eyed stage of egg development. No water mold was observed on the perch eggs using either formalin treatment regime. Median survival to the eyed stage of egg development was not significantly different between the treatments and approached 90%.  There was also no significant difference in egg survival to hatch. In addition, fry length at hatching, although relatively short overall, was not significantly different between the formalin treatment concentrations. The results of this study indicate that reducing daily 15-minute formalin concentration from 1667 to 834 mg/L during yellow perch egg incubation will not affect survival through hatch or larval length at hatching.

1959 ◽  
Vol 36 (1) ◽  
pp. 203-216 ◽  
Author(s):  
ANTHONY W. COCKING

1. The temperature at which 50% of a sample of roach (Rutilus rutilus) die within a week cannot be raised above 33.5° C. by raising the acclimatization temperature. 2. The roach is about as eurythermal as the yellow perch (Perca flavescens). 3. The mean asphyxial concentration of oxygen at 30 and 32°C is approximately 0.8 mg./l. 4. Median survival time at any lethal temperature increases with increase in acclimatization temperature; survival time for any acclimatization temperature decreases as test temperature increases; the temperature at which 50% of a sample die within a week rises by about 1° C. for each 3° C. rise in acclimatization temperature. 5. The behaviour, on transfer to higher temperatures, depends on the acclimatization temperature and the size of the jump in temperature and can be divided into five characteristic stages. 6. Dying fish develop a black pattern; myotomic swimming muscles die first and opercular muscles last. The heart was still beating when the fish were opened but the gall bladder was abnormal.


2015 ◽  
Vol 8 (1) ◽  
pp. 30-36
Author(s):  
Brett D. D’Arco ◽  
Jeremy L. Farrell ◽  
Sandra A. Nierzwicki-Bauer ◽  
Charles W. Boylen

Gill netting was carried out at 25 sites in Lake George, New York to determine if interbasin differences of yellow perch (Perca flavescens) exist. Fish relative weight, growth and diet were analyzed for 267 yellow perch. Yellow perch are known to be omnivorous in the lake eating zooplankton, benthos and small fishes in both the littoral and pelagic waters. The length-weight relationship exhibited a significant difference amongst the Narrows, North and South basins for condition constants (p < 0.05). Relative weights were consistently found to be below the general target range and had significant differences between the basins. Growth models of fish caught in the three basins showed variation in growth of yellow perch. The yellow perch from the North basin exhibited allometric growth, while those in the South and Narrows displayed isometric growth. The diets of yellow perch between the basins also were found to be different. Previous studies have noted differences between the basins with respect to chlorophyll a, chemistry, and biota. This study provides evidence of differences in the fishery amongst the basins that follow similar, previously defined, differences in chemistry.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
P Milani ◽  
L Obici ◽  
R Mussinelli ◽  
M Basset ◽  
G Manfrinato ◽  
...  

Abstract Background Cardiac wild type transthyretin (ATTRwt) amyloidosis, formerly known as senile systemic amyloidosis, is an increasingly recognized, progressive, and fatal cardiomyopathy. Two biomarkers staging systems were proposed based on NT-proBNP (in both cases) and troponin or estimated glomerular filtration rate, that are able to predict survival in this population. The availability of novel effective treatments requires large studies to describe the natural history of the disease in different populations. Objective To describe the natural history of the disease in a large, prospective, national series. Methods Starting in 2007, we protocolized data collection in all the patients diagnosed at our center (n=400 up to 7/2019). Results The referrals to our center increased over time: 5 cases (1%) between 2007–2009, 33 (9%) in 2010–2012, 90 (22%) in 2013–2015 and 272 (68%) in 2016–2019. Median age was 76 years [interquartile range (IQR): 71–80 years] and 372 patients (93%) were males. One hundred and seventy-three (43%) had atrial fibrillation, 63 (15%) had a history of ischemic cardiomyopathy and 64 (15%) underwent pacemaker or ICD implantation. NYHA class was I in 58 subjects (16%), II in 225 (63%) and III in 74 (21%). Median NT-proBNP was 3064 ng/L (IQR: 1817–5579 ng/L), troponin I 0.096 ng/mL (IQR: 0.063–0.158 ng/mL), eGFR 62 mL/min (IQR: 50–78 mL/min). Median IVS was 17 mm (IQR: 15–19 mm), PW 16 mm (IQR: 14–18 mm) and EF 53% (IQR: 45–57%). One-hundred and forty-eight subjects (37%) had a concomitant monoclonal component in serum and/or urine and/or an abnormal free light chain ratio. In these patients, the diagnosis was confirmed by immunoelectron microscopy or mass spectrometry. In 252 (63%) the diagnosis was based on bone scintigraphy. DNA analysis for amyloidogenic mutations in transthyretin and apolipoprotein A-I genes was negative in all subjects. The median survival of the whole cohort was 59 months. The Mayo Clinic staging based on NT-proBNP (cutoff: 3000 ng/L) and troponin I (cutoff: 0.1 ng/mL) discriminated 3 different groups [stage I: 131 (35%), stage II: 123 (32%) and stage III: 127 (33%)] with different survival between stage I and II (median 86 vs. 81 months, P=0.04) and between stage II and III (median 81 vs. 62 months, P&lt;0.001). The UK staging system (NT-proBNP 3000 ng/L and eGFR 45 mL/min), discriminated three groups [stage I: 170 (45%), stage II: 165 (43%) and stage III: 45 (12%)] with a significant difference in survival: between stage I and stage II (86 vs. 52 months, P&lt;0.001) and between stage II and stage III (median survival 52 vs. 33 months, P=0.045). Conclusions This is one of the largest series of patients with cardiac ATTRwt reported so far. Referrals and diagnoses increased exponentially in recent years, One-third of patients has a concomitant monoclonal gammopathy and needed tissue typing. Both the current staging systems offered good discrimination of staging and were validated in our independent cohort. Funding Acknowledgement Type of funding source: None


Liver Cancer ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 771-786
Author(s):  
Kerstin Schütte ◽  
Regina Schinner ◽  
Mathias P. Fabritius ◽  
Melina Möller ◽  
Christiane Kuhl ◽  
...  

<b><i>Introduction:</i></b> Extrahepatic spread is reported as a prognostic factor in patients with advanced hepatocellular carcinoma (HCC) receiving systemic therapy. However, clinical studies have reported conflicting results for the clinical impact of the pattern of tumor progression during treatment and the role of new extrahepatic metastases in length of survival. <b><i>Objective:</i></b> To evaluate the impact of extrahepatic metastases on survival in patients with HCC treated with sorafenib or with a combination of sorafenib and selective internal radiation treatment (SIRT). <b><i>Methods:</i></b> SORAMIC is a randomized, controlled trial comprising diagnostic, local ablation, and palliative cohorts. In the palliative cohort, patients not eligible for transarterial chemoembolization (TACE) were randomized 11:10 to SIRT plus sorafenib (SIRT + sorafenib) or sorafenib alone. This exploratory subanalysis evaluated the impact of extrahepatic metastases on survival. <b><i>Results:</i></b> In the intent-to-treat cohort, 216 patients were randomized to SIRT + sorafenib and 208 to sorafenib alone. Seventeen patients with distant organ metastases (bone, <i>n</i> = 11; adrenal glands, <i>n</i> = 5; peritoneum, <i>n</i> = 1) and 262 without distant metastases at study entry were analyzed in this substudy. Patients with (Group A) and without (Group B) distant organ metastases at study entry presented with a median survival of 11.3 and 14.8 months, respectively (<i>p</i> = 0.2807). During follow-up of patients with no organ metastases at baseline, extrahepatic disease progression occurred in 50 patients (19.1%). No statistically significant difference in survival was observed between patients without extrahepatic progression and those with new extrahepatic disease during treatment (14.8 vs. 14.9 months; <i>p</i> = 0.6483). Development of new pulmonary metastases during treatment significantly shortened median survival (7.6 vs. 15.0 months, <i>p</i> = 0.0060). <b><i>Conclusions:</i></b> This subanalysis of the SORAMIC trial suggests that in patients with liver-dominant advanced HCC, metastases to distant organs with the exception of pulmonary metastases do not in general exert a negative impact on patient prognosis. The choice of palliative treatment should incorporate a personalized analysis of the pattern of tumor distribution.


2000 ◽  
Vol 9 (2) ◽  
pp. 1-5 ◽  
Author(s):  
Ajith J. Thomas ◽  
Jack P. Rock ◽  
Christine C. Johnson ◽  
Linda Weiss ◽  
Gordon Jacobsen ◽  
...  

Object It has been suggested that synchronous brain metastases (that is, those occurring within 2 months of primary cancer diagnosis) are associated with a shorter survival time compared with metachronous lesions (those occurring greater than 2 months after primary cancer diagnosis). In this study the authors used data obtained from the National Cancer Institute's Surveillance, Epidemiology, and End Results Program to determine the incidence of synchronous brain metastases and length of survival of patients in a defined population of southeastern Michigan residents. Methods Data obtained in 2682 patients with synchronous brain metastases treated from 1973 to 1995 were reviewed. Study criteria included patients in whom at least one brain metastasis was diagnosed within 2 months of the diagnosis of primary cancer and those with an unknown primary source. The incidence per 100,000 increased fivefold, from 0.69 in 1973 to 3.83 in 1995. The most frequent site for the primary cancer was the lung (75.4%). The second largest group (10.7%) consisted of patients in whom the primary site was unknown. The median survival length was 3.3 months. There was no significant difference in the median survival in patients with primary lung/bronchus and those with an unknown primary site (3.2 months and 3.4 months, respectively). Conclusions Patients who present with synchronous lesions have a poor prognosis, and the predominant cause of death, in greater than 90% of cases, is related to systemic disease; however, despite poor median survival lengths, certain patients will experience prolonged survival.


1995 ◽  
Vol 52 (3) ◽  
pp. 464-469 ◽  
Author(s):  
Todd M. Koel ◽  
John J. Peterka

Laboratory-based bioassays were conducted to determine concentrations of sodium-sulfate type salinities that limit the hatching success of several fish species. Survival to hatching (SH) was significantly lower (P < 0.05) in sodium-sulfate type waters from Devils Lake, North Dakota, of ≥ 2400 mg/L total dissolved solids (TDS) than in fresh water of 200 mg/L. In waters of 200, 1150, 2400, 4250, and 6350 mg/L TDS, walleye (Stizostedion vitreum) SH was 41, 38, 7, 1, and 0%; northern pike (Esox lucius) SH was 92, 68, 33, 2, and 0%; yellow perch (Perca flavescens) SH was 88, 70, 73, 0, and 0%; white sucker (Catostomus commersoni) SH was 87, 95, 66, 0, and 0%; common carp (Cyprinus carpio) SH was 71, 69, 49, 63, and 25%.


1992 ◽  
Vol 49 (12) ◽  
pp. 2474-2482 ◽  
Author(s):  
Jay A. Nelson ◽  
John J. Magnuson

Little is known about the animals that occupy naturally acidic habitats. To better understand the physiological state of animals from temperate, naturally acidic systems, we compared metabolite stores and meristics of two yellow perch (Perca flavescens) populations in northern Wisconsin. One population originated from a naturally acidic, dystrophic lake (Acid-Lake-Perch, ALP) and had previously been shown to have enhanced tolerance to low pH. The second population came from two nearby interconnected circumneutral, mesotrophic lakes (Neutral-Lake-Perch, NLP). Perch were collected throughout the year to account for seasonal effects and to discern whether patterns of metabolite utilization differed between populations. ALP had smaller livers containing less glycogen and greater muscle glycogen content than NLP. The ALP also had significantly greater liver and visceral lipid contents, and females from this population committed a greater fraction of their body mass to egg production. We interpret these results as indicative of physiological divergence at the population level in yellow perch. These results are discussed as possible products of H+ -driven changes in metabolism and as possible products of different life history strategies between populations. Our results also show that perch living in acidic, dystrophic Wharton Lake are not acid stressed.


1977 ◽  
Vol 34 (10) ◽  
pp. 1774-1783 ◽  
Author(s):  
Lloyd L. Smith Jr.

In an investigation of the commercial fishery of Red Lakes, Minnesota, for the 46-yr period 1930–75, catch statistics were analyzed, and the dynamics of the perch and walleye populations were examined. Mean annual yields of walleye for two statistical periods, 1930–53 and 1954–75, were 309,900 and 245,100 kg, respectively for walleyes, and 96,400 and 109,500 kg for perch. Annual abundance (CPE based on average catches per day per 5-net units of gill nets) varied from 3.8 to 64.6 kg for walleye, and from 2.5 to 34.4 kg for perch. Causes of fluctuations in harvestable stock were directly related to strength of year-classes and to growth rate during the season of capture. Year-class strength was not related to the abundance of parent stock or of potential predators. The respective strengths of year-classes of perch and walleye in the same year were positively correlated (r = 0.859, P < 0.01), and are directly related to climatic factors. Growth rate of walleye in different calendar years varied from +30.7 to −42.2% of mean growth, and that of perch from +13.4 to −8.6% (1941–56). Growing season began in mid-June and was almost over by September 1. Walleye yield could be enhanced by starting harvest July 1 instead of early June. Perch yield could be improved by harvesting small perch. Key words: Percidae, Perca, population dynamics, Stizostedion, long-term yield


1997 ◽  
Vol 54 (8) ◽  
pp. 1903-1915 ◽  
Author(s):  
S A Thayer ◽  
R C Haas ◽  
R D Hunter ◽  
R H Kushler

Zebra mussels (Dreissena polymorpha) in enclosures located in an experimental pond adjacent to Lake St. Clair, Michigan, increased sedimentation rate but had relatively minor effects on percent organic matter and percent nitrogen content of sediment. In contrast, sediment from Lake St. Clair adjacent to zebra mussels was significantly higher in carbon than that 0.5 m away. Zebra mussels increase the nutritional value of surficial sediment and provide greater structural heterogeneity, which is probably more important in causing change among zoobenthos. Zoobenthos and yellow perch (Perca flavescens) diet were dominated by dipteran larvae and leeches. Zoobenthos was significantly different between enclosures with and without zebra mussels. Treatments with zebra mussels had significantly more oligochaetes and tended to have more crustaceans (isopods and amphipods). In June, yellow perch without zebra mussels consumed significantly more zooplankton, and those with mussels had more crustaceans in their diet. Zooplankton density was greater in treatments without zebra mussels. Yellow perch with zebra mussels grew significantly more than those without mussels. Zebra mussels in the enclosures neither reproduced nor were eaten by yellow perch; hence. the observed growth differences were due to indirect effects involving zebra mussel induced changes in benthic structure and biota.


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