Blood biochemistry parameters are valuable tools for monitoring fish health. Their baseline values are still undefined for a multitude of farmed fish species. In this study, changes in the blood profile of rainbow trout females (Oncorhynchus mykiss) from three farms were investigated using different biomarkers during the summer season. In the given context, the main water physicochemical parameters were investigated and twelve biochemical parameters were measured from blood samples of rainbow trout reared in the Fiad, Șoimul de Jos, and Strâmba farms. We selected these farms because the genetic background of the rainbow trout is the same, with all studied specimens coming from the Fiad farm, which has an incubation station. Forty-five samples were collected monthly (May to August) throughout summer to observe the changes in the blood profile of rainbow trout. Principal component analysis showed a clear separation both among the studied farms and months. Furthermore, significant correlations (p < 0.05) between the majority of the biochemical parameters were found, indicating that the environmental parameters can influence several blood parameters at the same time. The present study provides several useful norms for assessing the welfare of rainbow trout, indicating that the relationships among different parameters are important factors in interpreting the blood biochemical profiles.

The review assembles chronological data on Black Sea trout (Salmo labrax) from Romanian waters and brings up-to-date information related to the distribution of the species. The information used dates from 1909 to 2020 and includes books, articles, digital databases, field observations, and notes from different research fields such as ichthyology, biogeography, genetics, aquaculture, conservation, and ecology. Global distribution, migration, meristic characters, and aquaculture of the species were analyzed based on the recorded data from the specialty literature. New information related to a possible population of Salmo labrax inside the Carpathian Arch was discussed. In Romanian waters the species is found in the Black Sea, Danube, Danube Delta but the current paper proposes a new hypothesis, namely that resident populations can be found in rivers and lakes adjacent to the Carpathian Arch. The highest migration point of the Black Sea trout in the Danube was recorded near Corabia locality, Olt County, (43°46′25″N- 24°30′12″E). In the Danube Delta, it was caught in all the three branches (Sulina, Sf. Gheorghe and Chilia), and lagoonary complexes such as Razim-Sinoe. Sexually matured females were caught especially in Spring Season while unmatured specimens were caught in all seasons. Even if the species is protected under Romanian legislation, fishermen and anglers should report its presence when caught accidentally.

Gastrointestinal microbiota can be easily altered by common treatments, such as antibiotic therapy. However, the dysmicrobism induced by such a treatment may be counteracted by the administration of different beneficial microbes, such as probiotics. Therefore, this study aimed to establish the interaction between intestinal microbiota, antibiotic therapy, and sporulated bacteria, correlated with the evolution of growth indices. Twenty-five Wistar rats, females, were divided into five groups. Amoxicillin and a probiotic combination of Bacillus subtilis, Bacillus licheniformis, and Pediococcus acidilactici were administered according to each group’s purpose. The conventional growth indices were calculated and histological and immunohistochemical assessments were realized from intestinal samples. The results of the conventional growth indices suggested a beneficial effect when the antibiotic therapy was accompanied by probiotics, while for the groups where the dysmicrobism was present, the values for feed conversion ratio were negative. These findings were supported by the microscopic aspects of the intestinal mucosa, which suggested a decreased absorption capacity due to significant morphological changes. Moreover, the immunohistochemical reaction of the inflammatory cells from intestinal lamina propria was intensely positive for the same affected groups. However, for the control group and the group with antibiotic and probiotic treatment, the immunopositivity was significantly decreased. Probiotics based on bacillus spores administered simultaneously with the antibiotic offered the best restoration of the gut microbiota, a fact suggested by the absence of intestinal lesions, a normal food conversion ratio, and low expression of TLR4 and LBP immunomarkers.

The parameters studied were RBC, Ht, Hb, erythrocyte index MCV, MCH, MCHC, and oxidative stress through SOD and GPx. For each parameter, blood samples were collected at specimens weighing between 100-140g in the summer season, 250-280 g in the fall, 270-300g in the winter and 320-350g in the spring. At the specimens studied the highest values of GPx and SOD were recorded in the spring season due to the stress caused by massive precipitation. During the study, the water temperature ranged between 5.1° C in winter and 19.2° C in summer and O2 ranged between 8.30 mg/l in the summer and 10.20 mg / l in winter. For most parameters, the highest values were recorded in the spring season and the lowest in the summer season. The data obtained in each season on Oncorhynchus mykiss species do not indicate pathological conditions but more an adaptive fish response to environmental conditions and can serve as a database for future research on welfare of salmonids.

Given the scarce morphological data regarding the middle ear anatomy of this species, the paper attempts to describe the morphological and morphometrical data of the auditory ossicles in the badger. The study was performed using the standard morphological investigations and provides a complete morphological description of the ossicular assembly (malleus, incus and stapes) with some comparative features and attempts to provide a complete set of standardized metrical data for each ossicle. A more-detailed attempt to compare some functional aspects in the light of combined metrical ratios is also implied.