scholarly journals Эмбриональное и раннее личиночное развитие бурого терпуга Hexagrammos octogrammus (Scorpeniformes: Hexagrammidae) северной части Охотского моря

2021 ◽  
pp. 89-100
Author(s):  
R. R. Yusupov ◽  
◽  
Rus. R. Yusupov ◽  
Keyword(s):  
Standard Length ◽  
Sea Of Okhotsk ◽  
Early Ontogenesis ◽  
The Sea Of Okhotsk ◽  
Average Temperature ◽  
Total Length ◽  
Regional Features ◽  
External Feeding ◽  
Eggs And Larvae

The roe of Hexagrammos octogrammus from of the Northern part of the Sea of Okhotsk was incubated in an experiment. A detailed description of the morphology of the species development, from fertilization of eggs to the fry transition to external nutrition, accompanied by microphotographs of eggs and larvae fry in vivo, is given. It was established that the fertilized eggs of H. octogrammus from the northern part of the Sea of Okhotsk are 1.75 mm in diameter with fluctuations of 1.61-1.98 mm. Hatching of embryos occurs after 33.5 days of incubation at an average temperature of 11.5°C. Hatched yolk fry is 7.78 mm (7.15-8.06 mm) of TL (Total length) and 7.39 mm (6.83-7.68 mm) of SL (Standard length). Upon reaching TL of 8.74 mm (8.14-9.26 mm) and SL of 8.21 mm (7.63-8.86 mm), the fry switch to external feeding. The regional features of the masked greenling pigmentation in early ontogenesis are revealed.

scholarly journals Spawning and mortality of eggs and larvae produced by different brood sizes of Walking Catfish (Clarias batrachus L.)

2018 ◽  
Vol 3 (3) ◽  
pp. 78
Author(s):  
A. H. Sheikh ◽  
A. R. Mondal ◽  
B. C. Majumdar ◽  
A. Rayhan ◽  
M. N. Hossen
Keyword(s):  
Body Weight ◽  
Mortality Rate ◽  
Standard Length ◽  
Total Body Weight ◽  
Clarias Batrachus ◽  
Brood Stock ◽  
Total Length ◽  
Length Standard ◽  
Total Body ◽  
Eggs And Larvae

An experiment was carried out on the spawning and mortality of eggs and larvae of Magur, Clarias batrachus collected from brood-stock pond during the study period.The lowest spawn production (3774 eggs) was recorded in the fish having 23 cm total length and 115 g total body weight and the highest spawn production (10102 eggs) was recorded in the fish having 26.4 cm total length and 230 g total body weight. The spawn production was found to increase with the increase of total length,standard length and total body weight following the equations, Y= –13921+833.7X, r= 0.685, Y= 13965+909.8X, r= 0.667 and Y= 1326+33.02X, r= 0.810, respectively. The relationships between spawn production with total length, standard length and total body weight of the fish were found to be linear and significant (p<0.01). The lowest mortality rate (30.41%) was recorded in the fish having 26.4 cm total length and 224 g total body weight and the highest mortality rate (42.76%) was recorded in the fish having 23 cm total length and 125 g total body weight. The mortality rate of eggs and larvae was found to decrease with the increase of total length, standard length and total body weight of female brood following the equations, Y= 108.6–2.878X, r= –0.865, Y= 110.4–3.214X, r= –0.862 and Y= 54.99–0.108X, r= –0.970, respectively.The relationships between mortality rate of eggs and larvae with total length, standard length and total body weight of the fish were found to be linear and significant (p<0.01).

scholarly journals Taxonomic, morphometric and limnological assessment of the commercially important ichthyofauna of Sakhakot Stream, Malakand, Pakistan

2022 ◽  
Vol 82 ◽  
Author(s):  
M. Attaullah ◽  
U. Ullah ◽  
I. Ilahi ◽  
N. Ahmad ◽  
F.U. Rahman ◽  
...  
Keyword(s):  
Standard Length ◽  
Stream Fish ◽  
Wild Stock ◽  
Average Temperature ◽  
Total Length ◽  
Representative Species ◽  
Significant Difference ◽  
Fish Samples ◽  
Commercially Important ◽  
Mastacembelus Armatus

Abstract The present study was conducted for the taxonomic, morphometric and limnological assessment of the commercially important ichthyofauna of Sakhakot Stream, Malakand, Pakistan. The study area was divided into three sites along the water course namely Dargai Stream, Sakhakot Stream and Shergarh Stream. Fish samples were collected randomly during January to August 2017 with the help of fish gears. A taxonomic key was designed for the collected fish specimens. Ten fish species were identified belonging to 3 orders and 4 families. Family Cyprinidae was the dominant family with seven representative species while families Siluridae, Nemacheilidae and Mastacembelidae were represented by one species each. Lower mean total length and standard length was recorded in Puntius conchonius (Hamilton, 1822) as 9.2 ± 0.6 cm and 7.3 ± 0.6 cm respectively, while highest mean total length and standard length was recorded in Mastacembelus armatus (Lacepede, 1800) as 28.1 ± 1.7 cm and 15.9 ± 2.4 cm respectively. Mean pH of the water ranged from 6.1 at Shergarh Stream in August to 8.7 at Sakhakot Stream in January. Average temperature range was recorded from 10.9 °C in January at Dargai Stream to 18.7 °C in August at Shergarh Stream. No statistically significant difference was found for temperature (p = 0.96) and pH (p = 0.14) in the three water streams. The present study will provide a baseline for the rearing and enhancement of wild stock of the commercially important ichthyofauna in the field of aquaculture and fisheries.

Contribution to the flora of marine algae of the coastal zone of the northeastern part of the Sea of Okhotsk

2018 ◽  
Vol 52 (1) ◽  
pp. 63-73
Author(s):  
N. V. Evseeva
Keyword(s):  
Coastal Zone ◽  
Sea Of Okhotsk ◽  
Marine Algae ◽  
Herbarium Material ◽  
Northeastern Part ◽  
The Sea Of Okhotsk ◽  
The Family ◽  
First Time

The revision of the herbarium material, collected in the northern part of the Sea of Okhotsk in 1965–1966 and stored in VNIRO, allowed to expand the taxonomic list of macrophyte algae of the coastal zone of this area. The locations of discovery of 24 previously unmentioned species are described. Myrionema balticum, Ulvella repens, Syncoryne reinkei, Acrochaetium arcuatum were found in the Sea of Okhotsk for the first time. Most species new for the Sea of Okhotsk is represented by epiphytes of the family Ulvellaceae (Chlorophyta). The final taxonomic list of this region, including literature data, consists of 169 species.

CARBONATE DISSOLUTION AND ULTRASTRUCTURAL BREAKDOWN IN PLANKTONIC FORAMINIFERA IN THE SEA OF OKHOTSK

2017 ◽  
Author(s):  
Alexandra Romanova ◽  
Alexandra Romanova ◽  
Vladimir Anin ◽  
Vladimir Anin ◽  
Sergey Pletnev ◽  
...  
Keyword(s):  
Sea Of Okhotsk ◽  
Planktonic Foraminifera ◽  
Carbonate Dissolution ◽  
Calcite Dissolution ◽  
The Sea Of Okhotsk ◽  
Globigerina Bulloides ◽  
Neogloboquadrina Pachyderma ◽  
Thin Walled ◽  
Shell Fragments ◽  
Degree Of Fragmentation

80 sediment stations collected along the meridian transect across the Sea of Okhotsk were studied in order to reveal patterns of dissolution based on planktonic foraminifera. The degree of calcite dissolution intensity from planktonic foraminifera determined by different indices (degree of fragmentation, presence of susceptible to dissolution species, benthos/ plankton ratio). The highest degree of dissolution evidenced by a large number of shell fragments and corroding walls were found in sediments from the area of the Kuril Islands. The most revealing measure of probable dissolution of foraminiferal shells in the central part of the sea is a low number and lack of thin-walled species. The effects of dissolution on foraminiferal shells were studied for dominated species Neogloboquadrina pachyderma sin and Globigerina bulloides using a scanning electron microscope. The results are important for understanding processes of sedimentation, the paleo-oceanologial reconstructions and for obtaining reliable results in isotope analyzes.

Decapodid stage of Neocrangon communis (Decapoda, Crangonidae) from the eastern part of the Sea of Okhotsk

2016 ◽  
Vol 25 (1) ◽  
pp. 13-22
Author(s):  
N.A. Sedova ◽  
S.S. Grigoriev
Keyword(s):  
Sea Of Okhotsk ◽  
General View ◽  
Characteristic Shape ◽  
The Sea Of Okhotsk ◽  
First Time ◽  
Distinguishing Features

For the first time the morphology of the decapodid stage of Neocrangon communis is described in detail. The decapodid can be distinguished from those of the genera Argis, Crangon, and Mesocrangon by the morphology of their telson, antennae, antennulae, and carapace. The main distinguishing features of the decapodid of N. communis were two spines on medial line of the carapace, a short rostrum, relatively wide scaphocerite, characteristic shape and length of the terminal setae on the telson. Drawings of general view and some limbs are presented.

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