Comparative study of the plasma pharmacokinetics and tissue residues of trimethoprim in silky fowls and 817 broilers after single oral administration

Frontiers and emerging topics in a century of Silkie chicken research: insights, challenges, and opportunities

Silkie chickens are a unique breed renowned for their pigmentation, food and medicine homology properties, and distinctive appearance, making them highly valuable in exhibitions, as pets, in medicinal cuisine, and as a model for melanin research. Despite their vast potential, the growing volume of publications and patents related to Silkie chicken highlights the critical need for systematic organization, summarization, and analysis of this wealth of information. For the first time, this study employs bibliometric tools to summarize and analyze 114 years of research on Silkie chicken. Our study demonstrates that academic studies primarily focus on their nutritional value, melanin production, and genetic mechanisms, while patents emphasize food formulations, breeding methods, and purebred identification. Although there has been significant growth in publications and citations since 2001, international collaboration remains limited. This study presents the need for integrated and multidisciplinary research to unlock the full potential of Silkie chicken and provides a foundational framework for future studies and applications.

Study Rapid, Quantitative, and Simultaneous Detection of Drug Residues and Immunoassay in Chickens

Different levels of residual drugs can be monitored within a relatively safe range without causing harm to human health if the appropriate dosing methodology is considered and the drug withdrawal period is controlled during poultry and livestock raising. Antimicrobials are factors that can suppress the growth of microorganisms, and antibiotic residues in livestock farming have been considered as a potential cause of antimicrobial resistance in animals and humans. Antimicrobial drug resistance is associated with the capability of a microorganism to survive the inhibitory effects of the antimicrobial components. Antibiotic residue presence in chicken is a human health concern due to its negative effects on consumer health. Neglected aspects related to the application of veterinary drugs may threaten the safety of both humans and animals, as well as their environment. The detection of chemical contaminants is essential to ensure food quality. The most important antibiotic families used in veterinary medicines are β-lactams (penicillins and cephalosporins), tetracyclines, chloramphenicols, macrolides, spectinomycin, lincosamide, sulphonamides, nitrofuranes, nitroimidazoles, trimethoprim, polymyxins, quinolones, and macrocyclics (glycopeptides, ansamycins, and aminoglycosides). Antibiotic residue presence is the main contributor to the development of antibiotic resistance, which is considered a chief concern for both human and animal health worldwide. The incorrect application and misuse of antibiotics carry the risk of the presence of residues in the edible tissues of the chicken, which can cause allergies and toxicity in hypersensitive consumers. The enforcement of the regulation of food safety depends on efficacious monitoring of antimicrobial residues in the foodstuff. In this review, we have explored the rapid detection of drug residues in broilers.

Residue Elimination Patterns and Determination of the Withdrawal Times of Seven Antibiotics in Eggs of Taihang Chickens

The objective of this study was to examine the residue elimination patterns of seven antibiotics in the eggs of Taihang chickens under free-range conditions and develop suitable withdrawal times (WDTs). A total of 240 healthy Taihang chickens, aged 180 days, were randomly divided into eight groups of 30 birds each. The first seven groups were administered oxytetracycline, chlortetracycline, erythromycin, tylosin, tylvalosin, lincomycin, and tiamulin, respectively, in accordance with the maximum dosages and longest durations of treatment recommended by the Veterinary Pharmacopoeia of the People's Republic of China. Group 8 served as the control group, and the test period continued until no drug residue could be detected. The results demonstrate that the residues of oxytetracycline, chlortetracycline, tylosin, tylvalosin, and tiamulin throughout the test period were below the maximum residue limits (MRLs) outlined in GB 31650-2019, "National food safety standard-Maximum residue limits for veterinary drugs in foods". The egg yolk was identified as the target tissue for estimating the withdrawal time periods (WDTs) of these seven drugs. It was thus concluded that the recommended withdrawal time for tiamulin should be 0 days. However, the WDTs of oxytetracycline, chlortetracycline, tylosin, tylvalosin, were 2.8, 0.3, 2.4, and 7.4, respectively, when the upper limit of the 95% confidence interval was found to be lower than the MRLs. It was thus determined that the recommended WDTs for oxytetracycline, chlortetracycline, tylosin, and tylvalosin should be 3, 1, 3, and 8 days, respectively. In contrast, erythromycin and lincomycin exhibited concentrations below the permitted MRLs on days 7 and 8, respectively. However, the upper limits of the 95% confidence intervals for erythromycin and lincomycin were found to be below the MRLs when the WDTs were 11 and 8.9, respectively. This suggests that the recommended WDTs for these two antibiotics should be 11 days and 9 days.

Surveillance of Drug Residue Profiles in Gallus gallus domesticus (Silkie Chickens) in Taiwan

Veterinary drugs are extensively utilized in poultry farming for purposes such as disease prevention, disease treatment, and feed efficiency enhancement. However, the application of these drugs can lead to unacceptable residues in edible products. This study aimed to investigate the residue profiles of veterinary drugs in silkie chickens. A total of 130 chicken samples were collected from two major retail markets in Taiwan between 2022 and 2024. The analysis of drug residues was conducted using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The overall detection rate of drug residues was 57.7%, and most of these residues were found to be below the maximum residue limits. Among the detected drugs, trimethoprim was the most prevalent, followed by nicarbazin, robenidine, decoquinate, diclazuril, and sulfamonomethoxine. Notably, there was a 31.4% chance that different samples from the same flock would yield varying results. Furthermore, a positive correlation was observed between drug residues and sample weight. In conclusion, this study provides valuable epidemiological data on drug residue profiles in silkie chickens in Taiwan. In the future, it is highly recommended that veterinary drug residues be continuously monitored, and food product sampling protocols be adjusted annually to ensure ongoing compliance with safety standards and protect consumer health.

Comparison of gamithromycin residue depletion in yellow-feather and white-feather broilers after one single subcutaneous injection

This study aimed to compare the residue depletion of gamithromycin in yellow-feather and white-feather broilers, using Sanhuang and Arbor Acres chickens as typical examples, respectively. Each breed (54 chickens) received a single subcutaneous dose of gamithromycin at 7.5 mg/kg bodyweight (BW). Tissues, including muscle, skin + fat, liver, kidney, and injection site, were collected at 6 h, 3, 5, 7, 10, 14, 21, 28, and 35 d postdrug administration. Gamithromycin concentrations in these tissues were determined using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The kinetics of gamithromycin were analyzed in different tissues using a noncompartmental method in the Phoenix software. Differences were observed in gamithromycin concentrations and kinetic characteristics in both breeds of chickens, with higher residue concentrations and longer residue times found in yellow-feathered broilers. In Sanhuang broilers, the elimination rates of gamithromycin followed this order: injection site > muscle > liver > kidney > skin + fat. The corresponding elimination half-lives (t1/2λzs) in these samples were 1.22, 1.30, 1.71, 2.04, and 2.52 d, respectively. In contrast, in Arbor Acres broilers, a different order was noted: muscle > injection site > kidney > liver > skin + fat, with corresponding t1/2λzs of 1, 1.23, 1.88, 1.93, and 2.21 d, respectively. These differences may be related to variations in pigments in various tissues of chickens of the 2 breeds. However, further investigations are warranted to discern the underlying reasons.