Anabolic steroids induced changes at the level of protein expression: Effects of prolonged administration of testosterone and nandrolone to pigs

Synthetic derivatives of steroid hormones, specifically anabolic-androgenic steroids (AAS), have gained prominence due to their observed benefits in enhancing meat quality. The study replicated the administration of banned AAS and investigated their impacts on pigs to contribute to the understanding of animal biochemistry and to explore the feasibility of detecting AAS administration by employing a non-targeted analysis. The effects were corroborated by evaluating changes in the expression of selected proteins, as well as examining haematological and biochemical profiles and histological alterations. Exposure to AAS influenced the expression of proteins related to drug-metabolizing enzymes, muscle and lipid metabolism, kidney function, reproductive processes, immune system functions, and carcinogenic changes. The effects of AAS appear intricate and contingent on factors such as the specific drug used, dosage, and duration of administration. The results underscore that protein expression analysis holds promise as a valuable tool for detecting illicit AAS use in the fattening process.

Dosage Optimisation of Trimethoprim and Sulfamethoxazole for the Treatment of an Avian Pathogenic Strain of Escherichia coli in Broiler Chickens

Based on pharmacokinetic studies carried out according to the methodologies defined by the European Medicines Agency (EMA) using mass spectrometry analysis, a new formulation of a veterinary drug for the treatment of broiler chickens is proposed. Currently, the traditional trimethoprim-sulfamethoxazole drug used for broilers is applied in a 1:5 ratio, and the recommended dose is 45 mg kg-1 of live weight administered at 24 h intervals for 3 to 5 days. In this study, we propose a novel combination containing similar active substances in a newly established ratio of 1:4, with a recommended dosage of 20 mg kg-1 of live weight administered at 24 h intervals for 3 to 5 days. With this method, the currently recommended dose of the traditional trimethoprim-sulfamethoxazole drug used for broilers can be reduced by more than half. The efficacy of the newly designed formulation and dosage of the drug was verified in a bioassay for the treatment of broilers experimentally infected with an avian pathogenic strain of Escherichia coli. In the experiment, we compared the newly designed dosage with the traditional dosage in terms of efficacy and dosage. There were no statistically significant differences between the two drugs in efficacy regarding the survival of chickens after experimental infection or changes in their health status. The experimental results suggest that a significant reduction in the recommended daily dose of drugs containing trimethoprim and sulfamethoxazole for the treatment of bacterial infections in broilers is possible and can support the prudent use of antimicrobials, including the limitation of their overuse.

Pathotypes and Phenotypic Resistance to Antimicrobials of Escherichia coli Isolates from One-Day-Old Chickens

The aim of this work was to describe the pathotypes of Escherichia coli strains isolated from one-day-old chickens, as well as the occurrence of resistance and multidrug resistance (MDR) in these strains. A total of 429 mixed swabs from 4290 one-day-old chicks were examined between August 2021 and July 2023 (24 months) during routine point-of-destination inspections at 12 poultry farms in the Czech Republic. All samples were processed via cultivation methods using meat-peptone blood agar and Mc Conkey agar under aerobic conditions at 37 ± 1 °C for 18-24 h. The identification of the strains was performed using MALDI-TOF mass spectrometry. All confirmed strains of E. coli were screened via single or multiplex PCRs for the presence of genes encoding the virulence-associated factors iroN, cvaC, iss, felA, iutA, frz and tsh. Antimicrobial susceptibility tests were performed using the minimal inhibitory concentration (MIC) method, focusing on ampicillin, cefotaxime, tetracycline, doxycycline, enrofloxacin, florfenicol, amoxicillin with clavulanic acid and trimethoprim with sulfamethoxazole. A total of 321 E. coli strains (prevalence of 74.8%) were isolated, and 300 isolates were defined as avian pathogenic strains of E. coli (APEC) via multiplex PCR. Based on the defined virulence genes, the isolates were classified into 31 pathotypes. A total of 15.9% of the tested isolates were susceptible to all the tested antimicrobials. On the other hand, 20.5% of the isolates were identified as multidrug-resistant (8.7% of isolates were resistant to three antimicrobials, 7.3% to four antimicrobials, 3.6% to five antimicrobials and 0.9% to six antimicrobials). Monitoring pathogenic strains of E. coli in different animals and in the environment makes it possible to understand their spread in animal and human populations and, at the same time, reveal the sources of virulence and resistance genes.

The use of functional amino acids in different categories of pigs - A review

The present review deals with a particularly important topic: the use of functional amino acids in different categories of pigs. It is especially relevant in the context of the current efforts to reduce the use of antibiotics in pig farming and the search for possible alternatives to replace them. The review is based on the definition that functional amino acids (FAAs) are classified as dispensable amino acids, but with additional biological functions, i.e., not only are they used for protein formation, but they are also involved in regulating essential metabolic pathways to improve health, survival, growth, and development. We describe the mechanism of action of individual FAAs and their potential use in pigs, including glutamate, glutamine, arginine, branched-chain amino acids (i.e., leucine, isoleucine, and valine), tryptophan and glycine. The work is divided into three parts. The first part deals with the FAAs and their role in the overall health of sows and their offspring. The second part describes the use of functional amino acids in piglets after weaning. Part three examines the use of functional amino acids in growing and fattening pigs and their impact on meat quality.

Foodborne fluoxetine impacts the immune response in rainbow trout (Oncorhynchus mykkis)

The aim of this study was to reveal the effects of foodborne fluoxetine on morphological and condition profile, hematological profile, biochemical and oxidative stress indices on juvenile rainbow trout. The study was performed according to OECD Guideline No. 215. Fluoxetine was incorporated into Biomar 921 pellets at a dose of 0.047 mg/kg (environmental concentration), 0.577 mg/kg and 6.7 mg/kg. There was statistically significant change in hematological profile, including an increasing trend in neutrophil/lymphocyte ratio and a decreasing trend in the number of lymphocytes. Measurements of oxidative stress indicated decreased activity of the detoxifying enzyme glutathione-S-transferase in the liver and kidney. However, the measurement of GR, GPx, CAT, SOD activity, and TBARS showed no changes. Histopathological examination revealed damage to the proximal tubules of caudal kidney in exposed groups. This study confirms that fluoxetine has a significant effect on immune response.

Mass spectrometric identification and quantification of the antibiotic clavulanic acid in broiler chicken plasma and meat as a necessary analytical tool in finding ways to increase the effectiveness of currently used antibiotics in the treatment of broiler chickens

Clavulanic acid is a molecule with antimicrobial effect used in several livestock species treatment. Its inclusion in the treatment of infectious diseases of broilers requires determination of pharmacokinetic and pharmacodynamic parameters in order to determine the appropriate dosage for broilers and ensure safety of chicken products for human health. The present study describes the optimisation of analytical LC-MS/MS method for identification and quantification of clavulanic acid in broiler chicken plasma and meat. The limit of detection and the limit of quantification for the developed method were 3.09 μg·L⁻¹ and 10.21 μg·L⁻¹ for plasma and 2.57 μg·kg⁻¹ and 8.47 μg·kg⁻¹ for meat. The recoveries of the developed plasma and tissue extraction procedure were > 105.7% and > 95.6%, respectively. The achieved coefficient of variation of within-run precision ranged from 2.8 to 10.9% for plasma and from 6.5 to 8.5% for meat. The pharmacokinetic experiment was performed in 112 Ross broiler chickens assigned into time interval groups ranging from 10 min to 24 h in accredited animal facilities. Administered dose of clavulanic acid was 2.5 mg·kg⁻¹ according to the manufacturer’s recommendations. The pharmacokinetic parameters obtained from the experiment are as follows: C_max = 1.82 ± 0.91 mg·L⁻¹, T_max = 0.25 h, T_1/2 = 0.87 h, K_el = 0.80 ± 0.04 h⁻¹, AUC_0-∞ = 2.17 mg·h ·L⁻¹.

Identification and determination of deoxynivalenol (DON) and deepoxy-deoxynivalenol (DOM-1) in pig colostrum and serum using liquid chromatography in combination with high resolution mass spectrometry (LC-MS/MS (HR))

Deoxynivalenol (DON) is one of the most common mycotoxins produced by field fungi (especially Fusarium). Contamination of livestock feed is a significant risk factor, especially for pigs that are highly susceptible to the toxic effects of deoxynivalenol. In this study, validated ultra-high performance liquid chromatography (U-HPLC) combined with a HR-Orbitrap-MS analysis method is described for the identification and quantitative determination of the mycotoxin compounds (DON and deepoxy-deoxynivalenol (DOM-1)) in pig colostrum (milk) and serum. Pre-treatment of the samples involved a deproteinisation step with methanol followed by a purification step by solid phase extraction (HLB cartridges). The chromatographic separation was performed on a C18 column with 1.7 μm-particle size using a water-methanol mobile phase. Detection of analytes was achieved on the tandem hybrid mass spectrometer Q Exactive, with a heated electrospray ionisation probe measured in positive mode (H-ESI+). For the confirmation of identification, a mass spectrometer was utilized in the full scan mode with resolving power (PR) = 140,000 (FWHM) and for quantification analysis, it was utilized in the parallel reaction monitoring mode (PRM). The method has been fully validated according to the requirements of Commission Decision 2002/657/EC for confirmatory analyses, plus the addition of a mass accuracy (MA) parameter. For the confirmation of the presence of these analytes in pig colostrum and serum, matching of the retention time with mass accuracy for the precursor ion from MS and product ions from MS/MS was used. A deuterium isotopically labelled internal standard and a matrix-matched calibration curve were employed for quantification. The linear range of quantification was 0.5-20 μg L^-1 and the correlation coefficient (R²) was >0.999 for all calibrations. The limit of detection for DON and DOM-1 in colostrum was 0.48 μg L^-1 and 0.54 μg L^-1, respectively, and in serum 0.24 μg L^-1 and 0.36 μg L^-1, respectively. The limit of quantification for DON and DOM-1 in colostrum was 0.80 μg L^-1 and 0.89 μg L^-1, respectively, and in serum 0.39 μg L^-1 and 0.60 μg L^-1, respectively. The method was successfully evaluated using the obtained samples of pig colostrum and serum.

Perioperative interstitial CT-based brachytherapy boost in breast cancer patients with breast conservation after neoadjuvant chemotherapy

Intraoperative placement of catheters in the tumor bed during breast-conserving surgery (BCS) enables postponed targeted boost irradiation in high risk breast cancer patients. Twenty-three patients with high risk breast cancer underwent neoadjuvant chemotherapy and multifractionated perioperative brachytherapy as a boost to the tumor bed using three-dimensional (3D) CT-based planning. Plastic catheters for brachytherapy were implanted during surgery and targeted irradiation was delivered in the course of 2-3 weeks. Acute and late toxicities were scored according to the RTOG Common Toxicity Criteria. Cosmetic outcomes were assessed using the Harvard criteria. No major perioperative complications were recorded. Circumscribed wound infection occurred in one patient (4.3%). Only 3 patients (13%) experienced acute skin toxicity Grade 1. We observed no teleangiectasias or pigmentations. The cosmetic outcome at last follow-up visit was rated as excellent/good, in 82.6%, fair, in 13% and poor in 4.4% of patients, respectively. There was no evidence of disease recurrence after median follow-up of 43. 4 months. Systematic integration of the perioperative fractionated 3D CT-based HDR brachytherapy as a boost for patients with breast cancer after BCS is feasible and seems safe. It might be beneficial especially for women with high risk of local recurrence.