Edible insects such as the black soldier fly Hermetia illucens L. represent a potential and sustainable source of nutrients for food and feed due to their valuable nutritional composition, which can be modulated through dietary enrichment. The high content of saturated fatty acid (FA) of Hermetia illucens larvae fats can be modulated through dietary enrichment as a result of adding vegetable oils in the rearing substrate. Therefore, the present research aims to highlight the effects of a 10% addition of vegetable oils from five dietary fat sources (linseed oil, soybean oil, sunflower oil, rapeseed oil, and hempseed oil) on the growth, development, reproductive performance, and the fat and fatty acids profile of H. illucens. Oil inclusion in the larval diet improved (p < 0.05) the weight of larvae, prepupae, pupae, and imago without influencing (p > 0.05) the egg clutch weight and the number of eggs in the clutch. In addition, the larvae fatty acid profile was different (p < 0.001) according to the oil type, because the unsaturated FAs (UFA) increased from 11.23 to 48.74% of FAME, as well as according to the larvae age, because the saturated FAs decreased from 85.86 to 49.56% of FAME. Linseed oil inclusion led to the improvement of the FA profile at 10 days age of larvae, followed by hempseed and rapeseed oil. These three dietary treatments recorded the highest concentrations in UFA (29.94–48.74% of FAME), especially in polyunsaturated FA (18.91–37.22% of FAME) from the omega-3 series (3.19–15.55% of FAME) and the appropriate n–6/n–3 ratio. As a result, the degree of the lipid polyunsaturation index increased (17.76–41.44) and the value of the atherogenic (3.22–1.22) and thrombogenic (1.43–0.48) indices decreased. Based on the obtained results, it can be concluded that enriching the larval diet with these oils rich in UFA can modulate the larvae FA profile, making them suitable sources of quality fats for feed and indirectly for food.

The developmental stages of the black soldier fly, Hermetia illucens, are widely studied because there are several ways in which this species can be utilized. In this context, the aim of the current study is to determine the loss of weight of larvae of different weights between the prepupal and reproductive adult stages and their effect on the egg clutch quality parameters. The Hermetia illucens prepupae were categorized in 3 body weight classes. The weight loss was evaluated by weighing individuals in the prepupal, pupal and adult stages. The weight and length of the individuals were positively correlated in the pupal stage and adult females. There were significant losses of weight (P = 0.000) in the prepupal, pupal and adult stages in all three weight classes. In each weight class the relationship between weights was significant (P = 0.000) for all development stages. The results clearly indicate that the largest larvae of Hermetia illucens produced the adults with the best clutch quality parameters and the existence of significant positive correlations between body weight and both weight loss and the egg clutch quality parameters.

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.

Hermetia illucens is a sustainable and an increasingly bioeconomical source of nutrients for farm animals. It is still necessary, however, to improve our knowledge of the biological features of this species in order to maximize its use. The aims of this research were to evaluate the effect of the energy level of rearing diets on its body weight and fat-body reserves. The quantity and quality of the fats storred by the non-feeding stages of this insect and its reproductive performances were also studied. A control diet (CD - Gainesville diet) and three diets with progressively greater energy contents (kcal/kg ME) were formulated. The increase was achieved by including different amounts of maize, 40% (ED₁), 60% (ED₂) and 80% (ED₃), in these three diets. Abother diet (ED₄) consisted of fruit and vegetable waste. The results indicate that the body weight of larvae, prepupae, pupae and adult flies, as well as fat content of the larvae increased significantly (p ˂ 0.01) with increase in the energy content of the diets. There was a positive Pearson correlation between energy content of diets and body weight of adult flies. The heaviest egg clutches with the highest number of eggs/clutch (p ˂ 0.01) were laid by flies reared on the diets with the highest energy content. The quality of the fat stored by larvae did not influence the weight and number of egg laid.

The racer goby (Babka gymnotrachelus) is one of the well represented Ponto-Caspian goby species in most Danube Delta Biosphere Reserve lakes and channels, including Razim-Sinoe lagoon complex and lower sector of the Danube. Also, the presence of this species is noted in some lakes near Bucharest. The presence of this species in Transylvania has not been reported until now, when our team, while conducting ichthyologic investigations, captured seven specimens from Someș River and some of its tributaries, as follows: one specimen was caught in a channel adjacent to Țaga Mare Lake, one specimen was caught in Someşul Mare River (Mica village, Cluj County), two specimens were captured from the confluence of the Someşul Mic River and Fizeș River. Another two specimens were captured from Fizeş River (Fizeşu Gherlii village, Cluj County) and the last one was also caught from the Fizeş River (Sântioana village, Cluj County). It is possible that the species migrated in Someş Catchment from the Hungarian Danube sector, by the tributaries of Tisa River, or it might have originated from stocking material used in fish farms in Transylvania.The somatic, gravimetric and meristic measurements of the collected specimens were taken in the Acquaculture and Acquatic Organisms Phisyology laboratories from the University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca and correspond with those mentioned in the published literature regarding this species.

Smoking represents one of the oldest thermic processing methods of fish, and it was originally used to preserve fish for later meals, delaying spoiling. The objective of this study was to analyze the physicochemical and microbiological safety and quality of two traditionally smoked trout species (Oncorhynchus mykiss and Salvelinus fontinalis). We analyzed the effect of trout processed by traditional smoking, characterizing the samples according to the relationships existing between classical microbial analysis, physicochemical parameters, and the content of polycyclic aromatic hydrocarbons (PAHs). The microbial activity of the smoked fish was very low. Although traditional smoking implies high temperatures and direct exposure to the smoke, Benzo[a]pyrene, Benzo[b]fluoranthene, Benzo[k]fluoranthene, Dibenzo[a,h]anthracene, Benzo[g,h,i]perylene, and Indeno [1,2,3-cd]pyrene compounds had undetectable levels in the samples. The products obtained in this study did not exceed the maximum values imposed by EU legislation regarding the TVB-N values during the 30 days of the experiment. We conclude that traditionally smoked trout has many advantages in terms of quality and safety of the products. Thus, the obtained products are safe for consumption for at least 30 days after processing.