Genetic variation in survival of chinook salmon (Oncorhynchus tshawytscha) alevins exposed to an unidentified agent of mortality

Genome ◽  
1987 ◽  
Vol 29 (6) ◽  
pp. 839-845 ◽  
Author(s):  
R. E. Withler
Keyword(s):  
Genetic Variation ◽  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Mean Value ◽  
Unknown Etiology ◽  
Maternal Allele ◽  
Paternal Effects ◽  
Time To Death ◽  
The Mean ◽  
Family Survival

Mortality of an unknown etiology occurs after hatching and before emergence among Harrison River chinook salmon (Oncorhynchus tshawytscha) alevins incubated in the Chehalis River Hatchery, British Columbia. Inter- and intra-stock genetic variation for alevin survival and time to death was investigated at Chehalis Hatchery in factorial crosses among chinook salmon from the Harrison and Capilano rivers. Alevin survival by family ranged from 0 to 100%, with a mean value of 35.2%. The mean family survival of pure Harrison alevins (13.0%) was significantly lower than that of Capilano alevins (64.1%). For the Harrison stock, estimates of the heritability of survival were 1.05 ± 0.62 (sire component) and 0.03 ± 0.07 (dam component). For the Capilano stock, the corresponding estimates were 0.79 ± 0.53 and 0.80 ± 0.54. Family means of time to death ranged from 7.5 to 48 days after exposure to mortality-inducing agents. The mean times to death for pure Harrison (15.3 days) and Capilano (21.8 days) families were not significantly different. Sire and dam component heritability estimates for time to death were high for the Harrison stock (1.39 ± 0.87 and 0.71 ± 0.46) but low for the Capilano stock (0.06 ± 0.11 and 0.17 ± 0.18). Values of survival and time to death for the reciprocal interstock hybrid alevins generally fell between those of the parental stocks. Neither survival nor time to death differed significantly between the reciprocal hybrids, but both traits were more strongly influenced by sire than by dam. The possibility of asynchronous paternal and maternal allele activation during embryonic development was proposed as an explanation for the strong paternal effects observed in this study. Key words: Oncorhynchus, salmon, heritability, mortality.

scholarly journals The Relationship Between Digital Egg Coloration and Egg Survival in Landlocked Fall Chinook

2018 ◽  
Vol 7 (1) ◽  
pp. 31
Author(s):  
Holiday Robley ◽  
Michael E. Barnes
Keyword(s):  
South Dakota ◽  
Chinook Salmon ◽  
Color Index ◽  
Oncorhynchus Tshawytscha ◽  
Egg Survival ◽  
A Value ◽  
The Mean ◽  
The Relationship ◽  
Egg Coloration

Digital color values were collected from the eggs of 128 spawns from individual landlocked fall Chinook salmon Oncorhynchus tshawytscha females from Lake Oahe, South Dakota, USA, in 2008, 2009, 2015 and 2016. For all spawns, the mean (SE) a* value, a measure of red-green chromaticness, was 10.99 (0.27), and ranged from 3.98 to 18.71. Mean (SE) b* (yellow-green) was 20.27 (0.32), and ranged from 9.28 to 28.50. Mean (SE) L* (white-black) was 20.73 (0.48), and ranged from 3.98 to 18.71. Egg total color index also showed considerable variation, with a mean (SE) of 23.05 (0.37) and range from 11.70 to 31.64. Egg survival to the eyed-stage was weakly, but significantly, correlated to b* (r = 0.206), L* (r = 0.185), Chroma (r = 0.211), and Entire Color Index (r = 0.211). Spawns with no egg survival had eggs with significantly lower a* values compared to spawns where at least some of the eggs survived to the eyed stage. L*, a*, b*, Chroma, and Entire Color Index varied significantly among the years, but Hue and egg survival to the eyed stage did not. The results of this study indicate a possible link between egg color and landlocked fall Chinook salmon egg survival, possibly due to differences in the diets of feral broodstock females or their ability to deposit bodily carotenoids in the developing eggs.

Stress alters immune function and disease resistance in chinook salmon (Oncorhynchus tshawytscha)

1989 ◽  
Vol 120 (1) ◽  
pp. 135-142 ◽  
Author(s):  
A. G. Maule ◽  
R. A. Tripp ◽  
S. L. Kaattari ◽  
C. B. Schreck
Keyword(s):  
Disease Resistance ◽  
Immune Function ◽  
Chinook Salmon ◽  
Plasma Cortisol ◽  
Oncorhynchus Tshawytscha ◽  
Acute Stress ◽  
Vibrio Anguillarum ◽  
Time To Death ◽  
Mean Time

ABSTRACT We examined the effects of acute stress on the immune system and disease resistance of juvenile chinook salmon (Oncorhynchus tshawytscha) in laboratory and clinical trials. Immune function, as measured by the ability of lymphocytes from the anterior kidney to generate specific antibody-producing cells (APC) in vitro, was depressed 4 h after stress, when plasma cortisol levels were highest. At the same time, resistance to the fish pathogen, Vibrio anguillarum, was also depressed. Compared with controls, plasma cortisol and APC of stressed fish were unchanged after 24 h, and disease resistance was enhanced as evidenced by higher survival rate and longer mean time to death of mortalities. After 7 days, even though numbers of APC were depressed, plasma cortisol concentration and disease resistance did not differ from controls. This pattern was generally the same, independent of the type of stress applied: i.e. being held out of water in a dipnet for 30 s, manipulation during hatchery operations for 4 h, or transportation for 9 h. These and earlier findings suggest that similar endocrine-immune interactions operate in the mammalian and salmonid systems during acute stress. Journal of Endocrinology (1989) 120, 135–142

Extensive use of the Fraser River basin as winter habitat by juvenile chinook salmon (Oncorhynchus tshawytscha)

1991 ◽  
Vol 69 (7) ◽  
pp. 1759-1767 ◽  
Author(s):  
C. D. Levings ◽  
R. B. Lauzier
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Water Channel ◽  
Fraser River ◽  
Winter Habitat ◽  
Mean Size ◽  
System Data ◽  
The Mean ◽  
Juvenile Chinook ◽  
Stream Type

Habitat in the low-water channel of the mainstem Fraser River and larger tributaries during winter may be an unappreciated factor influencing production of stream-type chinook salmon (Oncorhynchus tshawytscha) in this system. Data from electrofishing surveys showed that shorelines were used by juvenile chinook from river km 110 to km 770. Almost the entire mainstem was therefore probably winter habitat, and major tributaries such as the Thompson, Quesnel, and Nechako rivers were also used. Estimated chinook density on the mainstem Fraser increased with distance upstream (maximum 0.30 m−2 at km 750 (Prince George)), but the highest density (0.99 m−2) in the surveys was observed on the Thompson River at Spences Bridge. The mean size of juvenile chinook decreased with distance upstream on the Fraser, ranging from 97 mm at km 110 to 65 mm at km 770. Chinook juveniles were feeding on Diptera, Trichoptera, and Plecoptera in winter. Some apparent growth was observed in the lower Fraser in early winter.

Fatty Acid Composition of Lipids in the Eggs and Alevins from Wild and Cultured Chinook Salmon (Oncorhynchus tshawytscha)

1993 ◽  
Vol 50 (3) ◽  
pp. 648-655 ◽  
Author(s):  
H. J. Ashton ◽  
D. O. Farkvam ◽  
B. E. March
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Total Lipid ◽  
Polar Lipid ◽  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Wild Fish ◽  
Marine Food Chain ◽  
Neutral And Polar Lipids ◽  
The Mean

The fatty acid profiles of lipids extracted from eggs and alevins of cultured chinook salmon (Oncorhynchus tshawytscha) were significantly different than those from eggs and alevins of wild fish of the same stock. The mean total concentrations of n3 fatty acids in the total lipid of eggs from wild and cultured broodstock were 40.2 and 29.4% and in the polar lipid 45.5 and 38.7% respectively. The mean concentrations of n3 fatty acids in the total lipid of alevins from wild and cultured broodstock were 35.4% and 23.2% and in the polar lipid 43.0 and 38.2%, respectively. The ratios of n3:n6 fatty acids were lower in both the neutral and polar lipids of eggs and of alevins from the cultured fish than in those of wild fish. The higher n3:n6 fatty acid ratios in the eggs and progeny of wild fish reflected the higher ratios in lipids of components of the natural marine food chain.

scholarly journals Study the usefulness of ascitic fluid cholesterol level in diagnosis of malignant related ascites

2018 ◽  
Vol 5 (2) ◽  
pp. 400
Author(s):  
. Mayank ◽  
B. P. Priyadarshi ◽  
Mahendra Singh ◽  
Ashok Kumar Verma ◽  
Tanu Midha
Keyword(s):  
Cholesterol Level ◽  
Ascitic Fluid ◽  
High Specificity ◽  
Clinical Problem ◽  
Malignant Ascites ◽  
Mean Value ◽  
Unknown Etiology ◽  
P Value ◽  
Malignant Group ◽  
The Mean

Background: The differential diagnosis of ascites is a common clinical problem. However, the capability to distinguish malignant from non-malignant causes of ascites using available biochemical techniques would obviate many expensive and time-consuming diagnostic studies on patients presenting with ascites of unknown etiology. Therefore, this study was planned to evaluate usefulness of ascitic fluid cholesterol level in diagnosis of malignant ascites.Methods: Author conducted an observational study in 80 patients, those admitted and willing to give consent in the department of Medicine, LLR and Associated Hospitals, GSVM Medical College, Kanpur from December 2015 to October 2017. All patient underwent full investigations to make the diagnosis of ascites malignant (20) and non-malignant (n=54), tubercular (7) and non-tubercular (47) groups. Six patients were excluded because the ascitic fluid analysis was suggestive of bacterial peritonitis. The data was processed in MS Excel and analysis was carried out using SPSS (23th version).Results: Author found that the mean value of ascitic fluid cholesterol in malignant group was 100.85+34.28 vs 6.7+2.5 in non-malignant group (p value <0.01) and the mean value of ascitic fluid cholesterol in malignant group was 100.80+34.28 vs 32.43+15.7 in tubercular group, so ascitic fluid cholesterol is highly specific (100%) and sensitive (65%) at cut off value of 100mg/dl in differentiating benign and malignant cause of ascites.Conclusions: Ascitic fluid cholesterol having high specificity, can be used for differentiating between non-malignant and malignant ascites. It can also be used to differentiate tubercular ascites from malignant ascites.

Mating system and distribution of enzyme genetic variation in bracken (Pteridium aquilinum)

1995 ◽  
Vol 73 (10) ◽  
pp. 1611-1617 ◽  
Author(s):  
Helena Korpelainen
Keyword(s):  
Genetic Variation ◽  
Gene Flow ◽  
Mating Systems ◽  
Vegetative Reproduction ◽  
Mean Value ◽  
Pteridium Aquilinum ◽  
History Of ◽  
The Mean ◽  
Allozyme Study ◽  
Growth And Reproduction

An allozyme study of populations of bracken, Pteridium aquilinum, revealed very low rates of intragametophytic selfing, on average 0.046, despite potential hermaphroditism and selfing of the gametophytes. The average number of genotypes per population was only 3.0 and mean heterozygosity equalled 0.015. Several populations consisted of only one genotype. The level of genetic divergence among populations was considerable. The mean value of the differentiation among populations (FST) was high (0.307) and the gene flow values were low, equalling 0.52 and 0.23 depending on the method of estimation. It is suggested that the life history of P. aquilinum, characterized by variable rates of spore production, vegetative reproduction, and the inefficiency of gametophyte growth and reproduction in established bracken stands, promotes genetic differentiation between populations. Key words: bracken, Pteridophyta, genetic variation, gene flow, mating systems.

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