Nanoemulsions with oleoresin of Copaifera reticulata (Leguminosae) improve anthelmintic efficacy in the control of monogenean parasites when compared to oleoresin without nanoformulation

Copaiba oil's bactericidal activity and its effects on health and zootechnical performance for Nile tilapia after oral supplementation

Tilapia is one of the most important farmed fish in the world and the most cultivated in Brazil. The increase of this farming favors the appearance of diseases, including bacterial diseases. Therefore, the aim of this study was to evaluate the bactericidal activity of copaiba oil, Copaifera duckei, against Streptococcus agalactiae and Flavobacterium columnare and the dietary effect of copaiba oil on zootechnical performance, hematological, biochemical, immunological, and histological analysis before and after an intraperitoneal infection (body cavity) with S. agalactiae in Nile tilapia. For this, fish were randomly distributed into 15 fiber tanks in five treatments (0, 0.25, 0.50, 0.75, and 1.0%) and fed with a commercial diet supplemented with copaiba oil for 30 days. After this period, the fish were randomly redistributed for the experimental challenge with S. agalactiae into six treatments (T0, T1, T2, T3, T4, and T5), the fish were anesthetized, and blood samples were collected to assess hematological, biochemical, immunological, and histological parameters. Copaiba oil showed bactericidal activity against Streptococcus spp. and Flavobacterium spp. in vitro. In addition, concentrations of 0.75 and 1.0% of copaiba oil have an anti-inflammatory effect and improve hematological and immunological parameters, increasing leukocyte numbers, albumin, and serum lytic activity. Furthermore, there is an increase in the intestinal villus length and tissue damage in groups at concentrations of 0.75 and 1.0% of copaiba oil. In conclusion, copaiba oil presented bactericidal activity against Streptococcus spp. and Flavobacterium spp. in vitro, and oral supplementation at concentrations of 0.75 and 1.0% compared to the control group enhanced non-specific immune parameters and digestibility in Nile Tilapia.

Efficacy of Carapa guianensis oil (Meliaceae) against monogeneans infestations: a potential antiparasitic for Colossoma macropomum and its effects in hematology and histopathology of gills

This study evaluated the efficacy of therapeutic baths with Carapa guianensis (andiroba) oil against monogeneans of Colossoma macropomum (tambaqui), as well as the hematological and histological effects on fish. Among the fatty acids identified in C. guianensis oil, oleic acid (53.4%) and palmitic acid (28.7%) were the major compounds, and four limonoids were also identified. Therapeutic baths of 1 hour were performed for five consecutive days, and there was no fish mortality in any of the treatments. Therapeutic baths using 500 mg/L of C. guianensis oil had an anthelmintic efficacy of 91.4% against monogeneans. There was increase of total plasma protein and glucose, number of erythrocytes, thrombocytes, leukocytes, lymphocytes and number of monocytes and decrease in mean corpuscular volume. Histological changes such as epithelium detachment, hyperplasia, lamellar fusion and aneurysm were found in the gills of tambaqui from all treatments, including controls with water of culture tank and water of culture tank plus iso-propyl alcohol. Therapeutic baths with 500 mg/L of C. guianensis oil showed high efficacy and caused few physiological changes capable of compromising fish gill function. Results indicate that C. guianensis oil has an anthelmintic potential for control and treatment of infections by monogeneans in tambaqui.

Combination of extractive techniques followed by HPLC-MS/MS analysis to monitor ent-agathic acid in fish treated with Copaifera duckei Dwyer

Plants are used as therapeutic alternatives in Veterinary Medicine, including therapies for food-producing animals. However, these medicinal resources can sometimes contain dangerous substances, and when used in animals that supply food, they stand out from the point of view of food safety. The diterpene ent-agathic acid, a component of Copaifera duckei oleoresin, is an example of substances already described with toxic activity in mammals. Thus, this study aimed to propose combining two extractive techniques followed by high-performance liquid chromatography coupled mass spectrometry analysis to monitor residues of ent-agathic acid in Piaractus mesopotamicus fillet treated in an immersion bath with Copaifera duckei oleoresin. An optimized combination of solid-liquid extraction (using acidified acetonitrile) and dispersive liquid-liquid microextraction (using acidified water and chloroform as dispersive and extracting solvent, respectively) was performed to recover the target analyte, added to the development of HPLC-MS/MS method with adequate validation parameters to quantify the ent-agathic acid present in the fish fillet. In vivo tests of residual persistence of ent-agathic acid in fishes treated with C. duckei oleoresin were performed, indicating the non-detection of the target diterpene (< 6.1 µg/mL). The combined extractive procedure followed by quantitative analysis in the in vivo test of residual persistence of the target analyte in fish indicated the absence of ent-agathic acid in all samples. Thus, the data found might contribute to understanding the use of oleoresins from C. duckei as an alternative to traditional veterinary products.

Antiparasitic potential of alternative treatments against larval stages of Lernaea cyprinacea

This study evaluated the potential of alternative treatments against larval stages of Lernaea cyprinacea. For in vitro test, the nanoemulsified oils of Pinus sp. acicule and oleoresin were evaluated, along with Biogermex® (commercial product based on citrus biomass). For this, the motility of five larvae of the same stage (nauplii or copepodite) were evaluated in a 96-well microplate. Using the best results, on the in vivo test, fries of Rhamdia quelen were submitted to a long-term immersion bath (96 h) containing different concentrations of the product diluted directly in the water. It was possible to notice the antiparasitic potential of the oleoresin and the acicule of Pinus sp., as well as the citrus biomass extract against the parasites. The nanoemulsified oils successfully inhibited the development of nauplii (10 mg L-1 in 24 h) and the fries showed to be tolerant to the presence of the compound (LC50 96 h-16.74 mg L-1). The concentration of 30.5 mg L-1 of Biogermex® eliminated the copepodites within 24 h, being more efficient than Pinus sp. when tested at the same stage, at the times analyzed. The results obtained indicate a potential use of these compounds as prophylactic agents against L. cyprinacea.