Quantitative determination of tetracyclines in medicated feed for food-producing animals by HPLC-DAD.

Tetracyclines are a group of antibiotic substances largely administered through medicated feed to control diseases in food-producing animals. Fine dosing of antibiotics contained in medicated feed is crucial for the success of the treatment as well as minimising potential threats such as the spread of antimicrobial resistance and the transfer of antibiotic residues in food. A rapid analytical method based on HPLC with diode array detection (HPLC-DAD) was developed to quantify oxytetracycline, chlortetracycline and doxycycline in medicated feed. The reported method underwent in-house validation and was found to be suitable for the quantification of three target tetracyclines within the concentration range of 40-1000 mg kg-1 in official routine analysis. The method was applied to 103 official samples in the framework of the Italian National Plan on animal feed during the years 2021-2023 and nine non-compliant concentrations were identified in swine and fish feed samples.

Fecal microbiota characterization of an Italian local horse breed.

The Bardigiano horse is a traditional native Italian breed with a rich history and peculiar characteristics. Local breeds are proven to have unique genetic traits developed over generations to adapt to defined geographical regions and/or conditions. The specific microbial communities that coexist within these animals are unraveled by studying their microbiota, which permits a further step in the characterization of local heritage. This work aimed to characterize Bardigiano horse fecal microbiota composition. The data obtained were then compared with published data of a mix of athlete breeds to evaluate potential differences among local and specialized breeds. The study involved 11 Bardigiano mares between 3 and 4 years of age, from which stool was sampled for the study. Samples were processed for 16S rRNA sequencing. Data obtained were analyzed and plotted using R, RStudio, and FastTree software. The samples analyzed were similar to what literature has reported on horses of other breeds and attitudes at higher taxonomic levels (from phylum to genera). While at lower taxonomic levels, the difference was more marked highlighting specific families found in the Bardigiano breed only. Weight, province of origin, and breeding sites significantly affected microbiota composition (p-value ≤0.02, p-value ≤0.04, and p-value ≤0.05, respectively). The comparison with athlete breed showed a significant difference confirming that animal and environmental factors are crucial in determining fecal microbiota composition (p-value <0.001). Understanding the microbiota composition in local breeds like the Bardigiano horse is crucial for preserving biodiversity, managing animal health, and promoting sustainable farming practices.

A New Method for Ivermectin Detection and Quantification through HPLC in Organic Matter (Feed, Soil, and Water).

Ivermectin is a macrocyclic lactone widely used in veterinary medicine for its broad-spectrum antiparasitic properties. It has been proven to be effective and safe. The purpose of this study was to develop a high-performance liquid chromatography method with a diode array detector for ivermectin screening in feed and water for animal consumption. Furthermore, the objective was to quantify ivermectin levels that were higher than 0.5 mg/kg in solid matrixes and 0.1 mg/kg in water. Doramectin was used as process standard. Samples were extracted using solid phase extraction with silica and C-18 columns. The method involved the use of high-performance liquid chromatography (HPLC) with a diode array detector (DAD). The results were interpreted using a calibration curve built with ivermectin standards at multiple concentrations (0.5, 1, 2, 5, and 12.5 mg/kg). Statistical evaluation of data was done using ANOVA. The data analysis showed that the linear regression was highly significant (P < 0.001), the intercept values were not significantly different from zero, and the correlation coefficient values (>0.999) indicated excellent linearity. Further tests demonstrated that this method is also useful when studying soil matrixes. The soil was dried and analyzed in the same way as feed; the same recoveries were realized on the spiked samples. The method is easy, inexpensive, precise, and repeatable; it requires very small amounts of sample.

Redox Status, Estrogen and Progesterone Production by Swine Granulosa Cells Are Impaired by Triclosan.

Triclosan is a chlorinated biphenolic with a broad spectrum of antiseptic activities used in cosmetics and hygiene products. Continuous exposure can lead to absorption and bioaccumulation of this substance with harmful health effects. In fact, previous studies have shown that Triclosan acts as an endocrine-disrupting chemical on reproductive organs, with consequent negative effects on reproductive physiology. Therefore, to assess potential adverse impacts on fertility, we tested Triclosan on swine granulosa cells, a model of endocrine reproductive cells. We examined its effects on the main features of granulosa cell functions such as cell growth (BrdU incorporation and ATP production) and steroidogenesis (17-ß estradiol and progesterone secretion). Moreover, since oxidant−antioxidant balance plays a pivotal role in follicular function, redox status markers (superoxide, hydrogen peroxide and nitric oxide production, enzymatic and non-enzymatic scavenging activity) were studied. Our results show that Triclosan significantly inhibits cell growth (p < 0.001), steroidogenesis (p < 0.001), superoxide and nitric oxide production (p < 0.001), while it increases (p < 0.05) enzymatic defense systems. Collectively, these data suggest a disruption of the main granulosa cell functions, i.e., proliferation and hormone production, as well as an imbalance in redox status. On these bases, we can speculate that Triclosan would impair granulosa cell functions, thus exerting negative effects on reproductive function. Further studies are needed to explore lower Triclosan concentrations and to unravel its mechanisms of action at gene level.