Disposition kinetics of albendazole and metabolites in laying hens

A brief review on models for birds exposed to chemicals

"A Who's Who of pesticides is therefore of concern to us all. If we are going to live so intimately with these chemicals eating and drinking them, taking them into the very marrow of our bones - we had better know something about their nature and their power."-Rachel Carson, Silent Spring. In her day, Rachel Carson was right: plant protection products (PPP), like all the other chemical substances that humans increasingly release into the environment without further precaution, are among our worst enemies today (Bruhl and Zaller, 2019; Naidu et al., 2021; Tang et al., 2021; Topping et al., 2020). All compartments of the biosphere, air, soil and water, are potential reservoirs within which all species that live there are impaired. Birds are particularly concerned: PPP are recognized as a factor in the decline of their abundance and diversity predominantly in agricultural landscapes. Due to the restrictions on vertebrates testing, in silico-based approaches are an ideal choice alternative given input data are available. This is where the problem lies as we will illustrate in this paper. We performed an extensive literature search covering a long period of time, a wide diversity of bird species, a large range of chemical substances, and as many model types as possible to encompass all our future need to improve environmental risk assessment of chemicals for birds. In the end, we show that poultry species exposed to pesticides are the most studied at the individual level with physiologically based toxicokinetic models. To go beyond, with more species, more chemical types, over several levels of biological organization, we show that observed data are crucially missing (Gilbert, 2011). As a consequence, improving existing models or developing new ones could be like climbing Everest if no additional data can be gathered, especially on chemical effects and toxicodynamic aspects.

Veterinary pharmaceuticals and declining Cape Griffon Vulture (Gyps coprotheres) numbers: A potential threat to developing embryos

Cape Vultures (Gyps coprotheres) are a vulnerable Old-World Vulture species in southern Africa. Of the numerous threats to their survival, malicious and accidental poisonings remain a major concern. Despite the dangers of poisonings little is however known about the more insidious effects of toxins on egg survival, despite the species known to have a long generational length. For this study, an extensive literature review focusing on veterinary pharmaceuticals was undertaken. Literature for vultures was scarce, with most studies focusing on the domestic chicken. Using information for domestic chickens, the risk was characterised from likely vulture exposure to production animal carcasses with residues of said drugs. From this various antibiotics, medetomidine and albendazole were identified with embryotoxic or teratogenic effects. We suggest that these drugs be tested to elucidate their dose-response relationship and/or mitigation measures to minimise vulture exposure.

Simultaneous quantitative determination of residues of abamectin, ivermectin, albendazole and its three metabolites in beef and chicken by HPLC-PDA

Antimicrobial drugs are frequently used in a combination or shuttle way to cope with coinfection of bacteria or parasites and prevent drug resistance, thus the accurate quantification of multiple drug residues in animal-derived foods is crucial to ensure food safety. Here, a simple and efficient high-performance liquid chromatography-photodiode array (HPLC-PDA) method was established for the simultaneous quantitative screening of six common residues of antiparasitic drugs, including abamectin (ABM), ivermectin (IVM), albendazole (ABZ) and the three metabolites of ABZ in beef and chicken. The LODs and LOQs for six target compounds in beef and chicken are determined to be 3.2 to 12.5 µg/kg and 9.0 to 30.0 µg/kg, respectively. The calibration curves show good linearity (R² ≥ 0.9990) between the peak area and concentration. The recoveries from the fortified blank samples are all above 85.10%. Finally, the applicability of the HPLC-PDA method is successfully demonstrated by the real sample analysis.

Multi-residue methodology for quantification of antiparasitics in hen eggs by LC-MS/MS: development, validation and application to 348 samples from Brazil

Analytical methodology for quantification of 15 antiparasitic drugs and their respective metabolites in laying hen eggs was optimized and validated. The method uses acetonitrile as solvent extraction, sodium chloride for salting-out, low-temperature purification and analysis by LC-MS/MS. A total of 348 egg samples were collected in 11 states of Brazil and 50% of the total samples presented antiparasitic residues, which were albendazole, fipronil, fenbendazole, ivermectin, oxibendazole and mebendazole. A total of 12.4% of the samples were considered non-compliant, and residues quantified in these samples were albendazole, fipronil, and mebendazole. Albendazole was always identified as albendazole sulfone. Only one sample presented fipronil and fipronil sulfone; all others exclusively the sulfone metabolite. Fenbendazole was characterized by the presence of both metabolites: sulfone and sulfoxide. Maximum limits adopted are based on the Normative Instruction 51/2019 of the Brazilian Health Regulatory Agency (ANVISA), but albendazole, fipronil, oxibendazole, ivermectin, and mebendazole do not have their maximum residue level established. In addition, metabolites of albendazole, fipronil and fenbendazole in eggs are not considered in this Instruction.

Simultaneous Determination of Albendazole and Its Three Metabolites in Pig and Poultry Muscle by Ultrahigh-Performance Liquid Chromatography-Fluorescence Detection

A fast, simple and efficient ultrahigh-performance liquid chromatography-fluorescence detection (UPLC-FLD) method for the determination of residues of albendazole (ABZ) and its three metabolites, albendazole sulfone (ABZ-SO₂), albendazole sulfoxide (ABZ-SO), and albendazole-2-aminosulfone (ABZ-2NH₂-SO₂), in pig and poultry muscle (chicken, duck and goose) was established. The samples were extracted with ethyl acetate, and the extracts were further subjected to cleanup by utilizing a series of liquid-liquid extraction (LLE) steps. Then, extracts were purified by OASIS^® PRiME hydrophilic-lipophilic balance (HLB) solid-phase extraction (SPE) cartridges (60 mg/3 mL). The target compounds were separated on an ACQUITY UPLC^® BEH C₁₈ (2.1 mm × 100 mm, 1.7 μm) chromatographic column, using a mobile phase composed of 31% acetonitrile and 69% aqueous solution (containing 0.2% formic acid and 0.05% triethylamine). The limits of detection (LODs) and limits of quantification (LOQs) of the four target compounds in pig and poultry muscle were 0.2-3.8 µg/kg and 1.0-10.9 µg/kg, respectively. The recoveries were all above 80.37% when the muscle samples were spiked with the four target compounds at the LOQ, 0.5 maximum residue limit (MRL), 1.0 MRL, and 2.0 MRL levels. The intraday relative standard deviations (RSDs) were less than 5.11%, and the interday RSDs were less than 6.29%.

Effects of feeding on the plasma disposition kinetics of the anthelmintic albendazole in laying hens

1. To optimise the use of albendazole (ABZ) as an anthelmintic in hens, the effects of fasting and type of diet on the plasma kinetics of ABZ and its metabolites were evaluated. 2. Twenty-four hens were distributed into 4 groups: In experiment I the Fed group were fed ad libitum, while the Fasted group was fasted over a 12-h period. In experiment II the Pelleted group was fed with pelleted commercial food, while the Grain group was fed with cereal grains. All the groups were treated with ABZ by oral route. Blood samples were taken and plasma analysed by HPLC. 3. ABZ and its metabolites albendazole-sulphoxide (ABZSO) and albendazole-sulphone (ABZSO2) were recovered in plasma in all the groups. The 12-h fasting period did not modify the disposition kinetics of ABZ in hens. The type of feed affected ABZ kinetics. ABZSO concentration profile was higher and detected for longer in the Grain group compared to the Pelleted group. Statistical differences were not found for AUC0-∞ values, whereas the T1/2for and T1/2el were different between groups. 4. Factors affecting ABZ kinetic behaviour should be taken into account to optimise its use to ensure the sustainability of the limited available anthelmintic therapeutic tools in avian parasite control.