Determination of Colistin B in Chicken Muscle and Egg Using Ultra-High-Performance Liquid Chromatography–Tandem Mass Spectrometry

Colistin, an imperative member of the polymyxin group, is a cationic peptide antibiotic. Itis also known as polymyxin E, but this peptide antibiotic has been forbidden for human consumption due to its high toxicity. Regrettably, this antibiotic is utilized as a feed additive and veterinary drug for animals. Due to the toxicity of colistin, the presence of its residue in the animal system represents a threat to human health regarding the consumption of meat, especially chicken. A novel method was proposed for quantifying colistin B in chicken muscles and eggs using ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS). In this method, extraction of colistin B from samples was achieved by mixing the sample with acidified methanol:water (1/1, v/v), followed by centrifugation and filtration by a membrane filter excluding solid-phase extraction (SPE) clean up, as well as evaporation steps. The analysis was conducted by optimized liquid chromatography–tandem mass spectrometry (LC–MS/MS), and method performance was assessed in terms of the limit of quantitation, specificity, selectivity, precision, linearity and recovery in coherence with the guidelines of SANTE and the Commission Decision 2002/657/EC. The result obtained from the study showed the limit of quantitation (LOQ) as 10 µg Kg−1 for muscles and 5 µg Kg−1 for eggs, with acceptable recoveries along with precision. The linearity was plotted in the range of 5–25 µg L−1 (solvent) for egg and 10–50 µg Kg−1 (matrix-matched) for muscles. The result of average recoveries showed the value of 70–94% (3.3–12% relative standard deviation (RSD)) for chicken muscles and 88–107% (2.5–18.6% RSD) for egg samples, which meets the criteria for acceptability of method according to both SANTE and 2002/657/EC guidelines. This proposed protocol provides a cost-effective solution for food testing labs by reducing the cost of the sample preparation by 60% along with the time required for SPE cleanup. Further, the optimized method was also tested on real samples collected from nearby provinces in Solan city, Himachal Pradesh, India, and three out of 20 muscles were found to have colistin B in the range of 50–560 µg Kg−1.

Nutritivna iskoristivost staroga crnog kruha u hranidbi pilića

The most important aspect of broiler production is feeding, whose costs represent about 70% of total costs. Thus, the growth of poultry production has been based on a strong consumer demand for products that are cheap, safe, and healthy. That kind of product is old bread, whose return from the store represent a problem for its remediation. For the use of the old bread as a feed, the European Union has promulgated a series of regulations and directives, which order a ban on its utilization without prior treatment. The most common treatments are pelleting and extrusion. In poultry, the upper limit for the use of the old bread in feedstuff is often prescribed and amounts to 15%. The aim of this paper was to determine a possibility to use 5 and 10% old brown pelleted bread in feed mixtures for broilers fattening. The study has shown that the addition of old bread significantly improves broiler production indicators. The best results and a more favorable ratio of omega 6 and omega 3 fatty acids in the chicken muscles were obtained in the group fed with a 10‐percent share of old brown bread (p<0.05). Such a processed old bread can be used as a new ingredient in animal feed production as a partial replacement for maize component.

The effect of silica-calcite sedimentary rock contained in the chicken broiler diet on the overall quality of chicken muscles

Opoka is a silica-calcite sedimentary rock chemically and structurally similar to diatomaceous earth (DE), composed mainly of silicon dioxide (SiO2), calcium carbonate (CaCO3), amorphous SiO. Opoka occurs predominantly in South Eastern Europe and Russia. Due to these specific properties investigation on the effect of opoka-enriched diet on chemical composition and overall quality of breast and leg muscles of broilers was initiated. Working samples showed a statistically significant increase in ash content or water content and a decrease in lipid content in the leg muscles of both male and female broilers (P<0.01). Furthermore, the addition of opoka to the diet increased WHC of leg muscles in females and hardness or chewiness of these muscles in both genders (P<0.05). The supplementation of broiler diet with opoka can be effectively applied to modify texture features of leg and breast muscle tissue which might, in turn, serve to regulate the nutritional and technological value of chicken meat.

Determination of Depleted Uranium Concentration and Histopathological Changes in Local Iraqi Fish and Chickens

This study aimed to determine the concentration of depleted uranium and the main histopathological changes in local fish and chickens at a selected Iraqi area suspected to be polluted with uranium. Different locations of Al-Tuwaitha region (Southern of Baghdad) were surveyed randomly to collect a total of 15 samples from each animal species. The animals were sacrificed and dissected at the site of collection. Muscle samples were collected to determine uranium concentrations using nuclear fission track analysis with CR-39 detectors. For histopathological changes, sample tissues from fish (liver, gills, and kidney) and chickens (liver, kidney, and lung) were collected and fixed in 10% neutral buffered formalin. The results showed that there was a significant elevation in uranium concentration in both fish and chicken muscles (1.94±0.77 µg/Kg and 2.19±0.82 µg/Kg, respectively) compared with recommended uranium concentration. Histopathological examination showed several effects included congestion and thickening of blood vessels walls, vacuolation, necrosis, fibrosis and inflammatory cells infiltration in most tissue section of collected organs. In conclusion, the uranium residues that found in both fish and chicken meats could raise the concerns about consumption of both animal species that had been bred in Al-Tuwaitha, and could be an indicator of environmental pollution with uranium in this region.

Genome-Wide Identification and Transcriptional Expression of the METTL21C Gene Family in Chicken

The chicken is a common type of poultry that is economically important both for its medicinal and nutritional values. Previous studies have found that free-range chickens have more skeletal muscle mass. The methyltransferase-like 21C gene (METTL21C) plays an important role in muscle development; however, there have been few reports on the role of METTL21C in chickens. In this study, we performed a genome-wide identification of chicken METTL21C genes and analyzed their phylogeny, transcriptional expression profile, and real-time quantitative polymerase chain reaction (qPCR). We identified 10 GgMETTL21C genes from chickens, 11 from mice, and 32 from humans, and these genes were divided into six groups, which showed a large amount of variation among these three species. A total of 15 motifs were detected in METTL21C genes, and the intron phase of the gene structure showed that the METTL21C gene family was conservative in evolution. Further, both the transcript data and qPCR showed that a single gene’s (GgMETTL21C3) expression level increased with the muscle development of chickens, indicating that the METTL21C genes are involved in the development of chicken muscles. Our results provide some reference value for the subsequent study of the function of METTL21C.

Evaluation of Antibiotics Residues in Chicken Meat Samples in Lebanon

Antibiotic residue in chicken is a human health concern due to its harmful effects on consumer health. This study aims at screening the antibiotic residues from 80 chicken samples collected from farms located in different regions of Lebanon. An optimized multi-class method for identification and quantification of 30 antibiotics from four different chemical classes (sulfonamides, tetracyclines, quinolones, and beta-lactams) has been developed by using liquid chromatography–mass spectrometry. The evaluation of antibiotics residues in 80 chicken muscles samples has shown that 77.5% of samples were at least contaminated with antibiotics residues, out of which 53.75% were exposed to co-occurrence of multidrug residues. The screening of the four antibiotics families has shown that ciprofloxacin (quinolones) represents the highest occurrence percentage (32.5%), followed by amoxicillin (β-lactams) (22.5%) and then tetracyclines (17.5%). Means of sarafloxacin, amoxicillin, and penicillin G residues levels were above the Maximum Residue Limit (MRL) recommended limit according to the European Union EC. This study revealed that chicken samples collected from Lebanese farms contain antibiotic residues. Guidelines for prudent use of antimicrobials agents for chicken should be adopted to reduce the prevalence of resistant Salmonella in chicken.