The structure of the skin, types and distribution of mucous cell of yangtze sturgeon ( Acipenser dabryanus ) / La estructura de la piel, los tipos y distribución de las células mucosas del esturión yangtze ( Acipenser dabryanus )

The structural characteristics of the skin, types and distribution of mucous cells of Yangtze sturgeon (Acipenser dabryanus) were studied at the light microscope level, stained with Haematoxylin-eosin (HE) and Alcian blue-periodie acid Schiff (ABPAS). The skin of both was composed of epidermis and dermis. The dermis was divided into stratum spongiosum and stratum compactum. The stained color of stratum compactum was stained more deeply than that of stratum spongiosum. The skin thickness displayed differences in the fish at different body positions. The thickest of epidermis layer was on the dorsal region for Yangtze sturgeon, reversely, the thinnest was the mandibular region; Stratum spongiosum on the mandibular region was the thickest, the stratum spongiosum of the maxillary region was not obvious. In summary, keratinized spines, a kind of keratin derivative, are widely distributed in the mandibular, ventral, dorsal, and caudal peduncle skin surface for Yangtze sturgeon, and some pit organs mainly present in the skin surface of the maxillary and ventral regions. In short, the small amount of mucous cells in the skin of Yangtze sturgeon and the type of mucous cell were main Type IV, nevertheless there was a distribution of a few Type III.

Se estudiaron las características estructurales de la piel, los tipos y la distribución de las células mucosas del esturión Yangtze (Acipenser dabryanus) con microscopio de luz, teñidas con hematoxilina-eosina (HE) y azul alcián-ácido de Schiff (AB-PAS). La piel estaba compuesta por epidermis y dermis. La dermis se dividía en estrato esponjoso y estrato compacto. El grosor de la piel mostró diferencias en los peces en diferentes posiciones del cuerpo. La capa más gruesa de la epidermis se observó en la región dorsal del esturión Yangtze; a la inversa, la más delgada en la región mandibular. El estrato esponjoso en la región mandibular era el más grueso, el estrato esponjoso de la región maxilar no era visualizado. En resumen, las espinas queratinizadas, un tipo derivado de la queratina, estaban ampliamente distribuidas en la superficie de la piel del pedúnculo mandibular, ventral, dorsal y caudal en el esturión Yangtze, y algunos órganos en fosas, presentes principalmente en la superficie de la piel de las regiones mandibular y ventral. En resumen, la pequeña cantidad de células mucosas en la piel del esturión Yangtze y el tipo de célula mucosa eran células principales tipo IV, sin embargo, se observaron algunas células tipo III.

Comparative Assessment of Biological and Fisheries Productivity of Caspian Sturgeons Species

Based on the model describing the dynamics of the number of generations of fish during the life cycle, the influence of growth and maturity on the biological and commercial productivity of conditional populations of Caspian sturgeon, formed from 1.0 million specimens of yearlings, was studied. On the biomass of conditional sturgeon populations, their gross output and catch are influenced by the length of yearlings, the size and age of maturity, the periodicity of spawning, the rate of linear and weight growth of individuals, and the degree of stocks catching. The highest yield of biomass and catch, obtained from 1 million yearlings, is observed in Beluga (Huso huso), then Ship Sturgeon (Acipenser nudiventris), Russian sturgeon (Acipenser gueldenstaedtii), Stellate Sturgeon (Acipenser stellatus) and sterlet (Acipenser ruthenus).

Some Hematological and Non-Specific Immune Responses of Rosehip (Rosa canina) - Fed Russian Sturgeon (Acipenser gueldenstaedtii Brandt & Ratzeburg, 1833) to Mycobacterium salmoniphilum

ABSTRACT In the study, the immunostimulant effects of rosehip (Rosa canina) on the health indicator hematological and non-specific immune parameters of Mycobacterium salmoniphilum-infected sturgeon were investigated. The rosehip was applied in the ratios of R5 (5%), R10 (10%), and R15 (15%) in three repetitions. After a 35-day feeding period, the fish were infected with M. salmoniphilum and analyzed after day 7, when symptoms were observed at elevated levels. Erythrocyte, erythrocyte indices, hemoglobin, hematocrit, leukocyte levels and the non-specific immune parameters including lymphocyte, monocyte, eosinophil, neutrophil, cytokines, phagocytic activity levels were comparatively examined using positive and negative control groups. The evaluations revealed that the RBC, Hb, Hct and WBC counts in the R15 group were significantly higher than those of the C+ group. Moreover, depending on the level of the immune response of the fish, among the immune parameters, significant increases in the lymphocyte, monocyte, cytokine, and phagocytic activity levels were observed in the R15 group. The results showed that the hematological and immune response to M. salmoniphilum infection was stimulated significantly in the 15% rosehip-fed fish. Hence, the effective dose of rosehip in fish was determined to be 15% and rosehip is suggested as an alternative to currently recommended immunostimulants.

Carnobacterium Isolated from Caviar of Sturgeon (Acipenser ruthenus) Farmed in Korea

Sturgeon aqua-cultured in Korea is mainly Acipenser ruthenus and its culture began in the early 2000's. In this study, Carnobacterium sp. was isolated from unprocessed caviar of aqua-cultured Acipenser ruthenus. The 16s rRNA nucleotide sequence obtained from Carnobacterium sp. isolate (accession no. KM236206) was deposited with GenBank and homologous with Carnobacterium divergens DSM 20623 and NBRC15683 strain. In conclusion, this is first report of isolation of Carnobacterium sp. from caviar of Acipenser ruthenus aqua-cultured in Korea. In the future, it must be ascertained whether Carnobacterium sp. degenerate of caviar or cause diseases in sturgeon.

Interrelationships among egg, larvae and maternal characteristics in Persian sturgeon Acipenser persicus

This study was aimed to observe the correlations among egg, larvae and maternal characteristics of Persian sturgeon. A total of 41 females were used and the variables including fertilization rate, incubation survival rate, larvae survival rate during yolk sac absorption (before feeding), and larvae survival rate after first feeding were determined. As a result, fertilization rate was positively correlated with three variables: incubation survival, larvae survival during yolk sac absorption, and GSI (gonadosomatic index). Also, maternal size (age, weight, total length) did not show a significant relation (P > 0.05) with incubation survival, larvae survival during yolk sac absorption and larvae survival at first feeding stage.