Allometry and Analysis of Morphometric Variation in the Bluegill, Lepomis macrochirus

Jet fuels such as JP-4 can be introduced into the environment and come in contact with aquatic biota in several ways. Studies in this laboratory have demonstrated JP-4 toxicity to fish. Benzene is the major constituent of the water soluble fraction of JP-4. The normal surface morphology of bluegill olfactory lamellae was examined in conjunction with electrophysiology experiments. There was no information regarding the ultrastructural and physiological responses of the olfactory epithelium of bluegills to acute benzene exposure.The purpose of this investigation was to determine the effects of benzene on the surface morphology of the nasal rosettes of the bluegill sunfish (Lepomis macrochirus). Bluegills were exposed to a sublethal concentration of 7.7±0.2ppm (+S.E.M.) benzene for five, ten or fourteen days. Nasal rosettes were fixed in 2.5% glutaraldehyde and 2.0% paraformaldehyde in 0.1M cacodylate buffer (pH 7.4) containing 1.25mM calcium chloride. Specimens were processed for scanning electron microscopy.

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MORPHOMETRIC VARIATION OF GENUS DOBSONIA FROM INDONESIAN PAP

Jurnal Natural ◽

10.30862/jn.v9i1.776 ◽

2010 ◽

Vol 9 (1) ◽

Author(s):

Aksamina M Yohanita ◽

Bambang Suryobroto ◽

Agustinus Suyanto

Keyword(s):

Scatter Plot ◽

Morphometric Variation

Studi morfometrik telah dilakukan dengan mengukur 32 karakter dari 176 spesimen Dobsonia dari Papua. Spesimen-spesimen Dobsonia diwakili oleh enam OTU, yaitu G, B, R, E, SP1, dan SP2. Analisis univariat menghitung seluruh spesimen dewasa yang terdiri dari 171 karakter badan dan sayap dan 176 karakter tengkorak dan gigi pada enam OTU tersebut. Selanjutnya digunakan uji-t dan PCA untuk menghitung G, B, dan R, sedangkan tiga OTU lain (E, SP1 dan SP2) tidak dihitung tetapi ikut diproyeksikan ke dalam scatter plot. Hasil uji-t (p<0.05) menunjukkan ada seksual dimorfisme pada D. minor dan D. beauforti. Pemisahan D. magna, D. minor, dan D. beauforti nyata pada karakter badan, sayap, dan gigi berdasarkan PCA. D. emersa terpisah dari spesies lainnya pada karakter badan dan tengkorak. Hasil scatter plot pada SP1 dan SP2 mengelompok dengan D. beauforti pada semua karakter (badan, sayap, tengkorak, dan gigi). Sebanyak 32 karakter yang diukur didapatkan karakter taksonomi yaitu WT, HB, dan TV untuk karakter badan; FA, TIB, dan DIG1P untuk karakter sayap; ONL, POW, PL, dan MH untuk karakter tengkorak; I2M2, M2M2, WM1, dan LM1 untuk karakter gigi. D. minor yang telah ditemukan di Pulau Waigeo tahun 2007 merupakan catatan baru penyebaran spesies ini, sebelumnya hanya tercatat di daratan utama Papua dan Pulau Yapen.

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The optimal dietary protein and lipid levels for juvenile hybrid sunfish ( lepomis cyanellus ♀ × Lepomis macrochirus ♂)

Aquaculture Nutrition ◽

10.1111/anu.13228 ◽

2021 ◽

Author(s):

Hengjia Ma ◽

Kai Liu ◽

Xiaoyu Feng ◽

Hui Huang ◽

Yubo Wu ◽

...

Keyword(s):

Dietary Protein ◽

Lepomis Macrochirus ◽

Lipid Levels ◽

Lepomis Cyanellus

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Changes in the Metabolic Rate and Blood Lactic Acid of Bluegill Sunfish, Lepomis macrochirus, Raf. following Severe Muscular Activity

Physiological Zoology ◽

10.1086/physzool.35.4.30155429 ◽

1962 ◽

Vol 35 (4) ◽

pp. 323-329 ◽

Cited By ~ 18

Author(s):

Alan G. Heath ◽

Austin W. Pritchard

Keyword(s):

Lactic Acid ◽

Metabolic Rate ◽

Lepomis Macrochirus ◽

Muscular Activity ◽

Bluegill Sunfish

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Effect of the Human Utilization of Northern Snakehead (Channa argus Cantor, 1842) on the Settlement of Exotic Fish and Cladoceran Community Structure

Sustainability ◽

10.3390/su13052486 ◽

2021 ◽

Vol 13 (5) ◽

pp. 2486

Author(s):

Jong-Yun Choi ◽

Seong-Ki Kim

Keyword(s):

Community Structure ◽

Fish Species ◽

Micropterus Salmoides ◽

Lepomis Macrochirus ◽

Nakdong River ◽

Exotic Fish ◽

Carnivorous Fish ◽

Channa Argus ◽

The Nakdong River ◽

Exotic Fish Species

Empirical studies suggest that changes in the density of top predators, such as carnivorous fish, in freshwater food webs, strongly affect not only fish communities but also various primary and secondary consumers. Based on these findings, we explored how differences in the utilization of carnivorous fish (i.e., Northern Snakehead, Channa argus) by humans affected the fish and cladoceran community structure as well as the settlement of exotic fish species (i.e., Lepomis macrochirus and Micropterus salmoides) in 30 wetlands located in the upper and lower reaches of the Nakdong River. Our results show that in the mid–lower reaches of the Nakdong River, the density of C. argus was low, while high densities of L. macrochirus and M. salmoides were observed. Exotic fish species are frequently consumed by C. argus, leading to a low density of L. macrochirus and M. salmoides in the upper reaches, which supported a high density of C. argus. However, in the mid–lower reaches, the density of L. macrochirus was high because of the frequent collection of C. argus by fishing activities. The dominance of L. macrochirus significantly changed the structure of cladoceran communities. L. macrochirus mainly feeds on pelagic species, increasing the density of epiphytic species in the mid–lower reaches. The continued utilization of C. argus by humans induced a stable settlement of exotic fish species and strongly affected the community structures of primary consumers in the 30 wetlands. The frequency of C. argus collection has to be reduced to secure biodiversity in the mid–lower reaches of the Nakdong River, which will reduce the proportion of exotic fish species and increase the conservation of native fish.

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Morphological Variations of Wild Populations of Brycon dentex (Characidae, Teleostei) in the Guayas Hydrographic Basin (Ecuador). The Impact of Fishing Policies and Environmental Conditions

Animals ◽

10.3390/ani11071901 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1901

Author(s):

Ana Gonzalez-Martinez ◽

Carmen De-Pablos-Heredero ◽

Martin González ◽

Jorge Rodriguez ◽

Cecilio Barba ◽

...

Keyword(s):

Discriminant Analysis ◽

Environmental Conditions ◽

Anthropogenic Activity ◽

Freshwater Species ◽

Fishing Pressure ◽

Wild Populations ◽

Morphometric Variation ◽

Morphological Variations ◽

Body Development ◽

The Impact

The Guayas, located in Ecuador, is the largest basin in the Pacific Ocean and has an inventory of 123 native freshwater species. Most of these are endemic species that are threatened or at-risk due to anthropogenic activity and the modification, fragmentation, and destruction of habitats. The aim of this study was to determine the morphometric variation in three wild populations of Brycon dentex in the Guayas basin rivers and their connections to fishing management and environmental conditions. A total of 200 mature fish were captured, and 26 morphometric parameters were measured. The fishing policies (Hypothesis 1) and environmental conditions (Hypothesis 2) were considered fixed factors and were validated by t-tests. The morphological variation among the three populations (Hypothesis 3) was validated through a discriminant analysis. Fishing policies and resource management were found to generate morphological differences associated with body development. In addition, the environmental conditions were found to influence the size and structure of Brycon dentex populations. The analyzed populations were discriminated by the generated morphometric models, which differentiated Cluster 1 (Quevedo and Mocache rivers) with high fishing pressure from Cluster 2 (Pintado river) with medium–low fishing pressure. Morphometric differentiation by discriminant analysis is a direct and economic methodology that can be applied as an indicator of diversity maintenance.

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