In the Atka mackerel Pleurogrammus monopterygius and chum salmon Oncorhynchus keta from the Bering Sea, lymphocytes predominate among leukocytes in peripheral blood. Atka mackerel lacks segmented neutrophils and basophils, while chum salmon lack eosinophils. The studied species differ in the size of leukocytes and the values of the leukocyte abundance index.

The cellular composition of the peripheral blood of the Baikal seal Phoca sibirica (Gmelin, 1788) has been studied. Various cells have been found in the blood smears: large and small lymphocytes; monocytes; and neutro-, eosino-, and basophils. Analysis has shown a high percentage of band neutrophils, eosinophils, and lymphocytes in the leukogram of young seal individuals when compared to adult individuals. Similar forms of leukocytes have been recorded during the study of some marine representatives of true seals (Phocidae). However, the proportion of band neutrophils is significantly lower in the leukograms of adult gray, harp, and ringed seals. The differences may be determined by physiological features and living conditions.

A comparative study of the composition of peripheral blood leukocytes of plunderfish and grey rockcod or squama caught in the Ross Sea has been carried out. Blood smears revealed cells of different morphofunctional characteristics and structure: lymphocytes, monocytes, neutro- and eosinophils, and blast cells. An analysis of the leukogram showed that the white blood of the studied species has a lymphoid character. In the rockcod leukogram, the proportion of lymphocytes is significantly higher, while that of monocytes and blast forms is lower. In the plunderfish, in comparison with the grey rockcod, the leukocyte cells of the same name are usually larger.

The cellular composition of leukocytes in the peripheral blood, head kidney and spleen was studied in individuals of three species of chars of the genus Salvelinus, white char S. albus, long–headed char S. kronocius and long-nosed char S. schmidti, as well as two forms, small-mouth and large-mouth chars living in Lake Kronotskoe. In the studied individuals, the proportion of lymphocytes of leukocytes in the peripheral blood was significant. The forms (species) of chars differed in the proportion of cell types, the size of leukocytes, as well as the intensity of leukopoiesis. The most significant differences in the proportion of different forms of leukocytes were found in the large-mouth char compared to other species and small–mouth char: high content of lymphocytes in blood smears, low content of monocytes in all tissues and organs, blast forms in the blood and neutrophils in the pronephros.

In pink salmon Onchorhynchus gorbuscha and chum salmon O. keta lymphocytes predominate among leukocytes in the peripheral blood during the marine period of life. In both species eosinophils are absent, while in pink salmon basophils are also absent. The proportion of segmented neutrophils and the size of lymphocytes, monocytes, and stab neutrophils are lower in chum salmon than in pink salmon.

— The composition of leukocytes was studied in the peripheral blood and hematopoietic organs (kidneys and spleen) of the Antarctic starry skate Amblyraja georgiana (Norman, 1938). Cells of several types with different morphofunctional characteristics and structures were found in the blood smears: lymphocytes, monocytes, neutrophils and eosinophils, and blast cells. A leukogram analysis showed that the white blood of A. georgiana is of a lymphoid type. In the kidney and spleen, most cells are blast forms.

The effect of testosterone on composition of leucocytes in the peripheral blood and immunocompetent organs of sterlet, Acipenser ruthenus, have been studied. It has been revealed that injection of physiological solution into the fish of control group and of testosterone into the experimental fish result in the changes in the proportions of certain types of white blood cells in the leucograms. The fish injected with hormone responded by decrease in the content of lymphocytes and increase in neutrophils and monocytes. The changes in the leucograms were most pronounced in peripheral blood and least pronounced in spleen.

Исследовано влияние тестостерона на состав лейкоцитов периферической крови и иммунокомпетентных органов стерляди Acipenser ruthenus. В лейкограммах опытных и контрольных рыб после введения соответственно гормона и физиологического раствора зарегистрировано изменение соотношения отдельных типов белых клеток крови. На воздействие гормона рыбы реагируют снижением содержания лимфоцитов и увеличением нейтрофилов и моноцитов. Наибольшие отклонения отмечены в лейкограммах периферической крови, наименьшие – в селезёнке.

Дана сравнительная характеристика лейкоцитов золотого карася Carassius carassius, обитающего в водоёмах Чернобыльской зоны отчуждения (Киевская область, Украина) и за её пределами в верхних незагрязнённых участках Киевского (Киевская и Черниговская области Украины) и Рыбинского водохранилищ (Ярославская область, Российская Федерация). Приведены состав и количественные характеристики отдельных типов лейкоцитов. Показано, что карась из зоны отчуждения Чернобыльской АЭС отличается от такового из незагрязнённых водоёмов уровнем содержания лимфоцитов, нейтро-, эозинофилов и клеток типа бласт. Сделан вывод о том, что радиационное загрязнение оказывает влияние на процессы дифференцировки стволовых кроветворных клеток рыб.

Analysis of data on utrastructure of granulocytes of freshwater and marine bony fish of orders Salmoniformes, Cypriniformes, and Perciformes showed that in all studied species there were revealed two types of granulocytes - neutrophils and eosinophils. The exception was the bluefish Pomatomus saltatrix L. whose pronephros hemopoietic tissue was found to contain one type of the granulocytic line - neutrophils. The identification parameters of granular leukocytes are specific granules filling the cytoplasm. The main form of specific granules in neutrophils of bony fish of various phylogenetic groups is an elongated granule with different distribution of fibrils or a granule that has crystalloid formed from fibrils. The main form of eosinophil granules - large, electron-dense, homogenous.

The comparative characteristics of leucocytes of the crucian carp Carassius carassius inhabiting the waterbodies of the Chernobyl exclusion zone (Kyiv oblast, Ukraine) and outside the zone in the upper nonpolluted areas of the Kyiv (Kyiv and Chernigov oblasts, Ukraine) and the Rybinsk reservoirs (Yaroslavl oblast, Russian Federation) is given. The composition and quantitative parameters of certain types of leucocytes are presented. It is shown that the crucian carp from the Chernobyl exclusion zone differs from that inhabiting the noncontaminated waterbodies by the level of lymphocytes, neutrophils and eosinophils, and blast cells. It is suggested that the radioactive contamination affects the processes of differentiation of stem hematopoietic cells in fish.

Analysis of data on ultrastructure of granulocytes of freshwater and marine bony fish of orders Salmoniformes, Cypriniformes, and Perciformes showed that in all studied species there were revealed two types of granulocytes-neutrophils and eosinophils. The exception was the bluefish Pomatomus saltatrix L. whose pronephros hemopoietic tissue was found to contain one type of the granulocyte line-neutrophils. The identification parameters of granular leukocytes are specific granules filling the cytoplasm. The main form of specific granules in neutrophils of bony fish of various phylogenetic groups is an elongated granule with different distribution of fibrils or a granule that has fibrils-formed crystalloid. Eosinophil granules are mainly of large, electron-dense, homogenous form.

The influence of cortisone on leucocytes composition in the blood of common carp (Cyprinus carpio L.) is studied. Following the hormone injection, the relative number of leucocytes decreased and the number of neutrophils and blast-form cells increased in the leucocyte spectrum of experimental fish.

Изучено влияние кортизона на состав лейкоцитов крови карпа Cyprinus carpio L. В лейкограмме опытных рыб после введения гормона зафиксировано уменьшение относительного количества лимфоцитов и увеличение нейтрофилов и бластных форм клеток.

Treatment of Lavsan fabric with a solution of chromium(III) benzoate complexes causes the highest rate of fixation of acid dye by the fabric and the highest equilibrium sorption, 2.5 times higher than this index for untreated fabric. The fabric also acquires higher capillarity. A simple method is proposed for production of chromium(III) benzoate and salicylate complexes and their composition is investigated spectrophotometrically as a function of the ratio of chromium ions and acid molecules in the solution.