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H. L. Kincaid

Publications and source records attributed to H. L. Kincaid.

At least 37 records · Page 2Linked to original sources
USGS1992

Retention of visible implant tags in lake trout and Atlantic salmon

Retention and readability of visible implant (VI) tags were evaluated in adult (2‐yearold) Atlantic salmon ( Salmo salar ), adult (4‐year‐old) lake trout ( Salvelinus namaycush ), and yearling (10‐month‐old) fish of both species. Tags were implanted in adipose eyelid tissue posterior to the eye. After 10 months, retention in yearlings was 49% by Atlantic salmon and 41% by lake trout. In adults, retention was 84% by Atlantic salmon and 45% by lake trout. Tag retention in yearling Atlantic salmon increased with fish weight at tagging; tag retention, by weight‐groups, was 0% for fish that weighed 20 g or less; 46% for 21–40‐g fish; and 71% for 41–99‐g fish. Tag retention in adults of Atlantic salmon and lake trout was not related to fish weight. After 10 months, the percentage of readable tags was 100% in yearling Atlantic salmon and 82% in adult Atlantic salmon, and 0% in yearling lake trout and 77% in adult lake trout. None of the tags in yearling lake trout were readable 294 d after implant, because of cloudiness of the adipose eyelid tissue. Tags recovered from fish with cloudy adipose tissue were readable. The proportion of total tag loss occurring in the first 70 d after tagging was 78% in yearling Atlantic salmon and 22% in adult Atlantic salmon, and 67% in yearling lake trout and 41% in adult lake trout. An illuminated magnifier lamp (1.7 × magnification) greatly increased the readability of the VI tags. The VI tags were effective for Atlantic salmon larger than 30 g, but they were not effective for lake trout.

Progressive Fish-Culturist↗
USGS1991

Rapid classification of nuclear cataracts lake trout

To examine lake trout ( Salvelinus namaycush ) in the field for cataract and noncataract eye abnormalities, we developed a procedure with a circular 1.7‐power illuminated magnifying lamp. A box in which the lamp is mounted facilitates its transport and provides a support base for the lamp during use in the field. A classification system was developed for assigning nuclear cataracts to four stages based on cataract size as a percentage of the total cross‐sectional area of the lens. When the method was used by newly trained technicians to screen 200,000 fall lake trout fingerlings into cataract and noncataract groups, the error rates were 1.7 and 7.7%, respectively. A technician could examine up to 2,800 fingerlings, 1,300 yearlings, or 700 3‐year‐old fish per day.

Progressive Fish-Culturist↗
USGS1991

Effects of orally administered steroids on lake trout and Atlantic salmon

Lake trout ( Salvelinus namaycush ) and Atlantic salmon ( Salmo salar ) fed 30 mg β‐estradiol/kg of feed for 100 d from first feeding had liver and kidney pathology similar to but much less severe than that previously reported for rainbow trout ( Oncorhynchus mykiss ). Mortality was not affected. Both lake trout and Atlantic salmon treated with estradiol weighed significantly less than control fish at the end of the treatment period and at 200 d posttreatment. Testosterone‐treated fish of both species weighed less than control fish at the end of the treatment period. By day 200 posttreatment, testosterone‐treated and untreated lake trout weighed the same, but testosterone‐treated Atlantic salmon were heavier than control fish. Estradiol treatment produced an all‐female population of Atlantic salmon but not of lake trout. Testosterone at 5 mg/kg feed increased the ratio of males to females in both species.

Progressive Fish-Culturist↗
USGS1989

Genetic differentiation among lake trout strains stocked into Lake Ontario

The lake trout Salvelinus namaycush is the focus of an international effort by fishery management agencies to restore this once‐native species to Lake Ontario. Evaluation of reproductive success and comparisons among stocked lake trout strains require genetic markers. We used allozyme variation to make genetic comparisons among strains of lake trout stocked into Lake Ontario. Forty‐two proteins presumed to be encoded by 102 loci were resolved electrophoretically; 18 loci were polymorphic. Among 16 samples from five principal origins (Finger Lakes, Great Lakes basin, northern New York–Adirondack, Manitoba, and mixed origins–Lake Ontario), the average observed heterozygosity was 0.029, and the proportion of polymorphic loci was 0.125. Significant differences occurred among the 16 samples at all 18 possible locus comparisons. The average F st value was 0.14. Hierarchical analysis indicated that the variation among samples within an origin was greatest within the Great Lakes basin, which included the greatest number of samples and represented the largest geographic area. Most variation observed among samples, however, occurred among origins. The 1983 and 1984 hatchery year classes produced from the 1978 Seneca brood stock did not differ significantly. The 1981 Seneca brood stock more closely resembled the sample of wild lake trout from Seneca Lake than progeny from the 1978 brood stock. The closer affinity of the 1981 brood stock to wild Seneca lake trout may be due to the larger number of wild adults from Seneca Lake used to found these fish than was used to establish the 1978 brood stock. Siscowet (“fat”) and “lean” lake trout from Lake Superior were significantly different from each other; however, the level of variation between them was not greater than that among samples from other origins, and thus did not support recognition of siscowet lake trout as a distinct subspecies. The Jenny Lake strain possessed a genetic affinity to the siscowet sample from Lake Superior. Historical reports about the origin of this strain suggest that siscowet lake trout from northern Lake Michigan may have been used to found this strain. Therefore, the Jenny Lake strain may serve as a gene source for the establishment of the siscowet lake trout in Lake Ontario. The substantial differentiation among lake trout strains reported here supports the feasibility of using allozyme markers to identify the parental sources of naturally produced young.

Lake Ontario↗
USGS1988

Growth, carcass composition, and taste of rainbow trout of different strains fed diets containing primarily plant or animal protein

Ten rainbow trout ( Salmo gairdneri ) strains were evaluated during early growth from 30 g to 250 g on two diets — one based on plant protein (soybean and cottonseed meal) and the other on animal protein (fish meal). Diets were formulated to be nutritionally isocaloric and isonitrogenous. Fish were fed identical starter diets until they weighed 30 g. Significant differences in growth rate were found attributable to fish strain. Differences associated with diet were nonsignificant. Percent dress-out data based on eviscerated weight, deboned weight, and fillet weight also showed significant differences in yield attributable to fish strain, but not to diet. Carcass composition varied among strains, but none of the differences could be attributed to diet. Organoleptic tests showed no differences in flesh acceptability associated with either fish strain or diet, and all trout tested were equally acceptable to human taste panels.

Aquaculture↗
USGS1987

Inheritance of duplicated fumarase and phosphoglucomutase loci in lake trout (Salvelinus namaycush)

Two polymorphic, duplicated loci (fumarase-1,2 and phosphoglucomutase-3,4), previously undescribed in salmonids, were examined in lake trout to determine their electrophoretic expression, mode of inheritance, and linkage associations. Both loci appear to be located on chromosomes which show residual tetrasomy. Neither locus pair shows joint segregation with other loci examined or with each other.

Heredity↗