Synergistic interaction of nanoparticles and probiotic delivery: A review

Nanotechnology is an expanding and new technology that prompts production with nanoparticle-based (1-100 nm) organic and inorganic materials. Such a tool has an imperative function in different sectors like bioengineering, pharmaceuticals, electronics, energy, nuclear energy, and fuel, and its applications are helpful for human, animal, plant, and environmental health. In exacting, the nanoparticles are synthesized by top-down and bottom-up approaches through different techniques such as chemical, physical, and biological progress. The characterization is vital and the confirmation of nanoparticle traits is done by various instrumentation analyses like UV-Vis spectrophotometry (UV-Vis), Fourier transform infrared spectroscopy, scanning electron microscope, transmission electron microscopy, X-ray diffraction, atomic force microscopy, annular dark-field imaging, and intracranial pressure. In addition, probiotics are friendly microbes which while administered in sufficient quantity confer health advantages to the host. Characterization investigation is much more significant to the identification of good probiotics. Similarly, haemolytic activity, acid and bile salt tolerance, autoaggregation, antimicrobial compound production, inhibition of pathogens, enhance the immune system, and more health-beneficial effects on the host. The synergistic effects of nanoparticles and probiotics combined delivery applications are still limited to food, feed, and biomedical applications. However, the mechanisms by which they interact with the immune system and gut microbiota in humans and animals are largely unclear. This review discusses current research advancements to fulfil research gaps and promote the successful improvement of human and animal health.

Multicolor emissive carbon dot-based fluorometric analysis platform for rapid quantification and discrimination of nitroimidazole antibiotic residues

The development of efficient, rapid, portable, and accurate analysis of veterinary drug residues in food matrices is in great demand for food safety assessment. Here, we have developed a smartphone-integrated platform for fluorometric quantification of metronidazole (MNZ) residues and constructed a sensor array for discrimination of different nitroimidazole antibiotics (NIIMs). Multicolor CDs (B-CDs, C-CDs, Y-CDs, and R-CD) were prepared and showed different fluorescence response to MNZ. The fluorescence of C-CDs was quenched Because of the inner filter effect (IFE) between the C-CDs and MNZ, while that of R-CDs was enhanced due to the passivation of surface defects by MNZ. Based on the response pattern, the fluorometric quantification of MNZ based on the fluorescence images of C-CD + R-CD system (R/G values) was achieved with a low detection limit of 0.45 μM. By designing a smartphone-integrated platform, the analysis can be completed within 20 min. In addition, a fluorescence sensor array based C-CDs and R-CDs was also developed. The unique fingerprint of each NIIMs was obtained by linear discriminant analysis (LDA) of the response patterns, indicating an effective discrimination of five NIIMs. Moreover, the platform was used for quantification of MNZ in food samples and the recoveries were within 84.0-106.3 % with relative standard deviations 1.2-10.2 %. Therefore, the proposed method shows great potential as a universal platform for rapid detection of veterinary drug residues.

Pimobendan controlled release guar gum printlets: Tailoring drug doses for personalised veterinary medicines

Treating chronic heart diseases in dogs is challenging due to variations in mass within and between species. Pimobendan (PBD), a veterinary drug only, is prescribed in specific cases of chronic heart disease in dogs and is available on the market in only a few different doses. Furthermore, the therapy itself is challenging due to the large size of the chewable tablets and the requirement for twice-daily administration. The development of customised and on-demand PBD medicines by three-dimensional (3D) printing has been proposed to circumvent these disadvantages. In this study, we designed controlled-release flavoured printlets containing PBD. We evaluated the use of two natural polymers, guar or xanthan gums, as the main component of the printing inks. Guar gum showed the better rheological behavior and printability by semisolid extrusion. The printlets were produced in three different shapes and sizes to allow dose customisation. Guar gum printlets showed a PBD controlled release profile, regardless of their shape or size. Therefore, we have demonstrated a novel approach for controlling PBD drug release and tailoring the dose by employing a natural polymer to produce 3D-printed tablets. This study represents a significant step towards the development of 3D-printed guar gum controlled-release formulations for veterinary applications.

An NADH/NAD+-favored aldo-keto reductase facilitates avilamycin A biosynthesis by primarily catalyzing oxidation of avilamycin C

Avilamycins, which possess potent inhibitory activity against Gram-positive bacteria, are a group of oligosaccharide antibiotics produced by Streptomyces viridochromogenes. Among these structurally related oligosaccharide antibiotics, avilamycin A serves as the main bioactive component in veterinary drugs and animal feed additives, which differs from avilamycin C only in the redox state of the two-carbon branched-chain of the terminal octose moiety. However, the mechanisms underlying assembly and modification of the oligosaccharide chain to diversify individual avilamycins remain poorly understood. Here, we report that AviZ1, an aldo-keto reductase in the avilamycin pathway, can catalyze the redox conversion between avilamycins A and C. Remarkably, the ratio of these two components produced by AviZ1 depends on the utilization of specific redox cofactors, namely NADH/NAD+ or NADPH/NADP+. These findings are inspired by gene disruption and complementation experiments and are further supported by in vitro enzymatic activity assays, kinetic analyses, and cofactor affinity studies on AviZ1-catalyzed redox reactions. Additionally, the results from sequence analysis, structure prediction, and site-directed mutagenesis of AviZ1 validate it as an NADH/NAD+-favored aldo-keto reductase that primarily oxidizes avilamycin C to form avilamycin A by utilizing abundant NAD+ in vivo. Building upon the biological function and catalytic activity of AviZ1, overexpressing AviZ1 in S. viridochromogenes is thus effective to improve the yield and proportion of avilamycin A in the fermentation profile of avilamycins. This study represents, to our knowledge, the first characterization of biochemical reactions involved in avilamycin biosynthesis and contributes to the construction of high-performance strains with industrial value.IMPORTANCEAvilamycins are a group of oligosaccharide antibiotics produced by Streptomyces viridochromogenes, which can be used as veterinary drugs and animal feed additives. Avilamycin A is the most bioactive component, differing from avilamycin C only in the redox state of the two-carbon branched-chain of the terminal octose moiety. Currently, the biosynthetic pathway of avilamycins is not clear. Here, we report that AviZ1, an aldo-keto reductase in the avilamycin pathway, can catalyze the redox conversion between avilamycins A and C. More importantly, AviZ1 exhibits a unique NADH/NAD+ preference, allowing it to efficiently catalyze the oxidation of avilamycin C to form avilamycin A using abundant NAD+ in cells. Thus, overexpressing AviZ1 in S. viridochromogenes is effective to improve the yield and proportion of avilamycin A in the fermentation profile of avilamycins. This study serves as an enzymological guide for rational strain design, and the resulting high-performance strains have significant industrial value.

Animal drug shortages limit veterinary therapeutic options and introduce artifacts in antimicrobial sales reporting

Supply chain issues disrupt veterinary care and cause downstream consequences that alter the practice of veterinary medicine. Antimicrobials are just 1 class of pharmaceuticals that have been impacted by supply chain issues over the last couple of years. Since February 2021, 2 sponsors/manufacturers of penicillin products have reported shortages in the active pharmaceutical ingredient. With the release of the 2021 Summary Report on Antimicrobials Sold or Distributed for Use in Food-Producing Animals by the FDA, a key finding was a 19% decrease in penicillin sales and distribution from 2020 to 2021. Herein, we provide our clinicians' professional perspective regarding how drug shortages, specifically that of penicillin, might contribute to misconstrued patterns in antimicrobial use and what can be done by veterinarians and the FDA to minimize the impact of an antimicrobial drug shortage on animal health and well-being.

Genome-edited rabbits: Unleashing the potential of a promising experimental animal model across diverse diseases

Animal models are extensively used in all aspects of biomedical research, with substantial contributions to our understanding of diseases, the development of pharmaceuticals, and the exploration of gene functions. The field of genome modification in rabbits has progressed slowly. However, recent advancements, particularly in CRISPR/Cas9-related technologies, have catalyzed the successful development of various genome-edited rabbit models to mimic diverse diseases, including cardiovascular disorders, immunodeficiencies, aging-related ailments, neurological diseases, and ophthalmic pathologies. These models hold great promise in advancing biomedical research due to their closer physiological and biochemical resemblance to humans compared to mice. This review aims to summarize the novel gene-editing approaches currently available for rabbits and present the applications and prospects of such models in biomedicine, underscoring their impact and future potential in translational medicine.

Ethnoveterinary medicinal plants and their utilization by indigenous and local communities of Dugda District, Central Rift Valley, Ethiopia

BACKGROUND

Ethnoveterinary medicinal plants have been used by the people of Dugda District in the primary health care system to treat various livestock ailments for generations, particularly, in underserved rural areas. However, these ethnoveterinary practices and medicinal plants are dwindling without proper documentation, due to undergoing socio-cultural and environmental changes. Hence, this study aimed at inventory and analysis of ethnoveterinary medicinal plants and the associated indigenous and local knowledge used in the treatment of livestock health problems in Dugda District.

METHODS

Data were collected from 378 local inhabitants through semi-structured interviews, 18 focus group discussions with 6 to 8 participants in each couple with participant field observations. Informant consensus factor (ICF), fidelity-level (FL) and relative importance value (RI) were used to evaluate the agreement of informants on ethnoveterinary practices, healing potential of medicinal plants and the most multipurpose species. Using standard taxonomic procedures, voucher specimens were collected, identified and deposited at the National Herbarium of Addis Ababa University.

RESULTS

In total, 64 medicinal plants of ethnoveterinary uses, belonging to 33 families were reported to treat 37 livestock health problems. Anthrax, inappetence and diarrhoea were said to be the most prevalent veterinary health problems treated by traditional medicinal plants. Family Fabaceae was the most widely reported (7 spp.), followed by Apocynaceae, Cucurbitaceae and Solanaceae (5 spp. each). Herbs were the dominant life forms (21spp.), followed by shrubs (20 spp.). The most commonly sought plant parts were leaves (55.25%), followed by roots (23.44%). The principal method of preparation was pounding remedial parts (46.85%) and mixing with cold water. The main route of administration was via oral application (72.67%), drenching diseased livestock. Withania somnifera and Kedrostis foetidissima were the most cited medicinal plants with 53 and 43 use reports (URs), respectively. ICF showed that respiratory diseases scored the highest value (0.94), while most of the reported medicinal plants were gastrointestinal agents. RI value analysis revealed that Croton macrostachyus had highest diversity of uses, followed by K. foetidissima and W. somnifera. Ethnoveterinary uses of some medicinal plants such as Phytolacca dodecandra, Calpurnia aurea, Cyphostemma cyphopetalum and Verbascum sinaiticum as prophylaxis against rabies were a new input for ethnoveterinary database.

CONCLUSION

The study revealed that the people of the Dugda District are endowed with rich ethnoveterinary knowledge and medicinal plants. However, ethnoveterinary knowledge associated with medicinal plant species significantly differ (P < 0.05) between general and key informants, young and matured age groups and informants' educational level. This infers the impact of mode of ethnoveterinary knowledge transfer, literacy, modern education and globalization on ethnoveterinary uses of medicinal plant species. And also most of the medicinal plants are found in wild habitats with nearly no conservation attention. Therefore, it is imperative to implement participatory conservation actions for medicinal plants in collaboration with traditional institutions (Gada system). The disparity of ethnoveterinary knowledge could be also minimized through awareness creation among local communities about the knowledge and its revitalization. Furthermore, medicinal plants, which are widely utilized and multipurpose, should be screened for their phytochemicals, pharmacological and toxicological activities to confirm ethnoveterinary uses and for future development of veterinary pharmaceuticals.

Prenatal amoxicillin exposure induces developmental toxicity in fetal mice and its characteristics

Amoxicillin, a widely used antibiotic in human and veterinary pharmaceuticals, is now considered as an "emerging contaminant" because it exists widespreadly in the environment and brings a series of adverse outcomes. Currently, systematic studies about the developmental toxicity of amoxicillin are still lacking. We explored the potential effects of amoxicillin exposure on pregnancy outcomes, maternal/fetal serum phenotypes, and fetal multiple organ development in mice, at different doses (75, 150, 300 mg/(kg·day)) during late-pregnancy, or at a dose of 300 mg/(kg·day) during different stages (mid-/late-pregnancy) and courses (single-/multi-course). Results showed that prenatal amoxicillin exposure (PAmE) had no significant influence on the body weights of dams, but it could inhibit the physical development and reduce the survival rate of fetuses, especially during the mid-pregnancy. Meanwhile, PAmE altered multiple maternal/fetal serum phenotypes, especially in fetuses. Fetal multi-organ function results showed that PAmE inhibited testicular/adrenal steroid synthesis, long bone/cartilage and hippocampal development, and enhanced ovarian steroid synthesis and hepatic glycogenesis/lipogenesis, and the order of severity might be gonad (testis, ovary) > liver > others. Further analysis found that PAmE-induced multi-organ developmental and functional alterations had differences in stages, courses and fetal gender, and the most obvious changes might be in high-dose, late-pregnancy and multi-course, but there was no typical rule of a dose-response relationship. In conclusion, this study confirmed that PAmE could cause abnormal development and multi-organ function alterations, which deepens our understanding of the risk of PAmE and provides an experimental basis for further exploration of the long-term harm.

retail stores by persistent environmental pollutants, pesticides and veterinary drugs

Studies have reported health risks associated with seafood contamination, but few data exist on levels in commercially available seafood in the US. To better understand, the magnitude of foodborne exposure and identify vulnerable populations in the US, we measured concentrations of veterinary drugs, persistent organic pollutants (POPs) (polycyclic aromatic hydrocarbons [PAHs], polybrominated diphenyl ethers [PBDEs] and polychlorinated biphenyls [PCBs]), and legacy and current-use pesticides in 46 seafood samples purchased from retail outlets. Measured levels were used to estimate risk based on available maximum residue limits (MRLs) and toxic equivalence (TEQ) factors for analytes. Only seventeen of the 445 analytes were detected, at low substance frequencies. However, half of the samples tested positive for one or more analyte, with total concentrations ranging from below the limit of detection (LOD) to as high as 156 µg/kg wet weight. Based on the risk assessment for individual pesticides and veterinary drugs, the hazard quotients (HQ) were all <1, indicating no risk. However, for the sum of PCB126 and PCB167, two dioxin-like PCBs detected in our samples, the TEQ was nearly two orders of magnitude higher than the WHO limits in one catfish sample. Moreover, vulnerable groups with higher rates of consumption of specific fish types may face higher risks.

Efficient treatment of veterinary pharmaceutical industrial wastewater by catalytic ozonation process: degradation of enrofloxacin via molecular ozone reactions

The study focused on the efficacious performance of bimetallic Fe-Zn loaded 3A zeolite in catalytic ozonation for the degradation of highly toxic veterinary antibiotic enrofloxacin in wastewater of the pharmaceutical industry. Batch experiments were conducted in a glass reactor containing a submerged pump holding catalyst pellets at suction. The submerged pump provided the agitation and recirculation across the solution for effective contact with the catalyst. The effect of ozone flow (0.8-1.55 mg/min) and catalyst dose (5-15 g/L) on the enrofloxacin degradation and removal of other conventional pollutants COD, BOD5, turbidity was studied. In batch experiments, 10 g of Fe-Zn 3A zeolite efficiently removed 92% of enrofloxacin, 77% of COD, 69% BOD5, and 61% turbidity in 1 L sample of pharmaceutical wastewater in 30 min at 1.1 mg/min of O3 flow. The catalytic performance of Fe-Zn 3A zeolite notably exceeded the removal efficiencies of 52%, 51%, 52%, and 59% for enrofloxacin, COD, BOD5, and turbidity, respectively, achieved with single ozonation process. Furthermore, an increase in the biodegradability of treated pharmaceutical industrial wastewater was observed and made biodegradable easily for subsequent treatment.

Marbofloxacin combined with heavy rare-earth ions makes better candidates for veterinary drugs: crystal structure and bio-activity studies

Marbofloxacin (MB) is a newly developed fluoroquinolone antibiotic used especially as a veterinary drug. It may be regarded as the improved version of enrofloxacin owing to its antibacterial activity, enhanced bioavailability, and pharmacokinetic-pharmacodynamic (PK-PD) properties. In this study, nine heavy rare-earth ions (Y, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) were selected in light of their potential antibacterial activity and satisfactory biosafety to afford the corresponding rare-earth metal complexes of MB: the MB-Ln series. Their chemical structures and coordination patterns were characterized using IR spectroscopy, HRMS, TGA, and X-ray single-crystal diffraction analysis. Our results confirmed that all the MB-Ln complexes yielded the coincident coordination modes with four MB ligands coordinating to the Ln(III) center. In vitro antibacterial screening on five typical bacteria strains revealed that the MB-Ln complexes exhibited antibacterial activities comparable with MB, as indicated by the MIC/MBC values, in which Escherichia coli and Salmonella typhi were the most sensitive ones to MB-Ln. Furthermore, the MB-Ln complexes were found to be much less toxic in vivo than MB, as suggested by the evaluated LD50 (50% lethal dose) values. All the MB-Ln series complexes fell in the LD50 range of 5000-15 000 mg kg-1, while the LD50 value of MB was only 1294 mg kg-1. Furthermore, MB-Lu, as the selected representative of MB-Ln, could effectively inhibit the activity of DNA gyrase, the same as MB, suggesting the primary antibacterial mechanism of the MB-Ln series. The results demonstrated the good prospects and potential of metal-based veterinary drugs with better drug performance.

Influence of a single oral dose of trazodone on intradermal histamine reactivity in clinically healthy dogs

BACKGROUND

Drug interactions are significant considerations for intradermal testing (IDT). Trazodone (TRZ) is an anxiolytic and selective histaminergic (H1 ) antagonist with no interaction in human prick tests; however, interaction in canine IDT is unknown.

HYPOTHESIS/OBJECTIVES

Trazodone will not adversely affect intradermal histamine reactions in dogs.

ANIMALS

Fourteen nonanxious, nonatopic, healthy client-owned dogs were enrolled in this randomised, blinded, cross-over study.

MATERIALS AND METHODS

Dogs were randomised to receive low-dose TRZ (4 mg/kg) (Teva Pharmaceuticals), high-dose TRZ (8 mg/kg) or no TRZ per os two hours before intravenous sedation with dexmedetomidine (5 mcg/kg) (Dexdomitor; Zoetis). Intradermal testing was performed with five quadrupling dilutions of histamine (1:100,000 to 1:25,600,000 w/v; Greer) and 0.9% saline (Hospira), observing a minimum two weeks washout period between treatments. Two observers, who were blinded to treatment and the identity of the injections, evaluated each test using previously established subjective and objective methods.

RESULTS

The mean wheal diameter of histamine 1:1,600,000 w/v was significantly smaller with low-dose TRZ (4 mg/kg) compared to the control group (p = 0.048; repeated measures ANOVA with post hoc Tukey's test). For all other histamine dilutions and saline, mean wheal diameter was not significantly different among groups. There were no significant differences in the subjective scores of all histamine dilutions and saline (p > 0.05; Friedman test).

CONCLUSION AND CLINICAL RELEVANCE

A single oral dose of TRZ does not adversely affect intradermal histamine reactions in dogs.

Simultaneous determination of praziquantel, fipronil, eprinomectin, (S)-methoprene, their key related substances and butylated hydroxytoluene (BHT) in a topical veterinary drug product by a single stability indicating high performance liquid chromatography method

A simple, robust and QC (quality control) friendly high performance liquid chromatography (HPLC) method was developed and validated for simultaneous determination of four active pharmaceutical ingredient [namely fipronil, (S)-methoprene, eprinomectin, and praziquantel] and their key degradation products in a broad-spectrum topical finished product. Typical sample of the finished product contains a total of 30-plus peaks of interest. Analytes were separated on a HALO C18 column (150 mm × 4.6 mm i.d., 2.7 µm particle size) with a gradient elution at 50 °C column temperature and 0.6 mL/min flow rate. Detection wavelength of 245 nm is used for praziquantel, eprinomectin and their degradation products, 265 nm for (S)-methoprene and its degradation products and 280 nm for fipronil and its degradation products and for the antioxidant, BHT. Mobile phase of the method is composed of 10 mM potassium phosphate buffer and 1,4- Dioxane (98/2, v/v, pH 5.0) as mobile phase-A, and EtOH/MeOH/MeCN/IPA (86/4/6/4, v/v/v/v) as mobile phase-B. All analytes of interest were adequately separated by this single HPLC method. The stability-indicating capability of the method has been demonstrated by successfully separating the degradation products in the stressed degraded samples of the finished product. Limit of quantitation (LOQ) and limit of detection (LOD) of the method is 0.3% and 0.1% of target analytical concentration for each individual API in the finished product. This method has been demonstrated to be sensitive, robust, specific, accurate and stability-indicating for analysis of the topical drug product containing praziquantel, fipronil, eprinomectin and (S)-methoprene.

[Exposure Level and Risk Impact Assessment of Pesticides and Veterinary Drugs in Aquaculture Environment]

To explore the exposure level of pesticides and veterinary drugs in an aquaculture environment and its impact on the ecological environment, this study took the aquaculture environment in Shanghai as an example, and samples of water, sediment, and inputs from 40 major aquaculture farms were collected from July to September 2022. The types and contents of pesticides and veterinary drugs were screened using high-performance liquid chromatography-electrostatic field orbital ion trap mass spectrometry, and the risk quotient (RQ) method was used to assess the ecological risk of pesticide contamination in water and sediment. The results showed that 13 drugs were screened out from 204 samples (72 samples of water, 72 samples of mud, and 60 samples of input), namely, chlorpromazine, carbendazim, thiophanate, diazepam, florfenicol, simazine, amantidine, diazepam, trimethoprim, ciprofloxacin, ofloxacin, mebendazole, and enrofloxacin. Among them, 12 species were found in water samples with concentrations ranging from 0.016 μg·L-1 to 2.084 μg·L-1. The concentrations of seven species in the mud samples ranged from 0.018 μg·kg-1 to 23.101 μg·kg-1. The results showed that there were four types of inputs, ranging from 1.979 μg·kg-1 to 101.940 μg·kg-1. Seven drugs were found in both water and sediment. The risk quotient (RQ) results showed that there were some high and middle risks in both water and sediment samples of aquaculture farms, and the ecological risks of carbendazim were the highest in both water and sediment samples of aquaculture farms; the RQ values were 3.848 and 1.580, respectively, indicating high risk. It is suggested to strengthen the control and management of exogenous pesticides and veterinary drugs in aquaculture environments to protect the ecosystem health of the aquaculture environment.

Catchment-scale rapid transfer of livestock pharmaceuticals under Mediterranean climate

Various pharmaceuticals are essential for livestock farming, but some are highly toxic to aquatic life if they reach surface water bodies. Mediterranean Climate is characterized by dry summers followed by intense autumn storms. We studied the effect of these climatic conditions on the risk of pharmaceutical residues transfer to streams at the catchment-scale. Pharmaceutical products routinely used in the study area, as well as their application frequency and season, were identified through interviews with farmers. As a proof a concept, three veterinary pharmaceuticals (Fenbendazole (FBZ), Mebendazole (MBZ) and Ivermectin (IVM)) were chosen as model chemicals based on their relatively high usage, their specificity to represent different types of livestock (swine, sheep and cattle), and their ability to be analyzed using the same analytical method. Stream water was analyzed during low flow periods and at high frequency (up to 2 h-1) during flood events. The selected veterinary pharmaceuticals were not detected during low flow, but FBZ and MBZ reached high concentrations for short periods during floods. Due to the event-driven nature of their transfer, a significant load of veterinary pharmaceuticals can reach the river and cause temporary but significant degradation of water quality (e.g. for FBZ, the water concentration reached up to 355 times the predicted no effect concentration (PNEC)). This indicates that special care should be taken to avoid keeping freshly treated livestock on pastures that may become hydrologically connected under wet conditions. In addition, it suggests that low-frequency monitoring is not sufficient to detect those high concentration levels that exist during very short periods.

Production and certification of BOTS-1: bovine muscle-certified reference material for incurred veterinary drug residues

A freeze-dried bovine muscle-certified reference material (CRM), known as BOTS-1 (DOI: https://doi.org/10.4224/crm.2018.bots-1 ), containing incurred residues of commonly used veterinary drugs was produced and certified for the mass fraction of eight veterinary drug residues. Value assignment was carried out using liquid chromatography tandem mass spectrometry (LC-MS/MS) methods in conjunction with isotope dilution and standard addition approaches involving stable isotope internal standards. Data from the National Research Council of Canada (NRC), Canadian Food Inspection Agency (CFIA), United States Department of Agriculture (USDA), and the Federal Office of Consumer Protection and Food Safety in Germany (BVL) were used for value assignment. Results for two drug residues were also obtained through an international inter-laboratory comparison CCQM-K141/P178 organized under the auspices of the International Bureau of Weights and Measures (BIPM). Quantitative NMR (1H-qNMR) was used to characterize primary standards of all veterinary drugs certified. The certified mass fractions of the veterinary drug residues were 490 ± 100 µg/kg for chlorpromazine, 44 ± 4.4 µg/kg for ciprofloxacin, 3.3 ± 1.4 µg/kg for clenbuterol, 9.5 ± 0.8 µg/kg for dexamethasone, 57 ± 4.8 µg/kg for enrofloxacin, 3.0 ± 0.4 µg/kg for meloxicam, 12.4 ± 1.2 µg/kg for ractopamine, and 2290 ± 120 µg/kg for sulfadiazine with expanded uncertainties quoted (95% confidence) which include the effects due to between-bottle inhomogeneity, instability during long-term storage and transportation, and characterization.

Interactions Between Biologic Therapies and Other Treatment Modalities

Biologic therapies are becoming increasingly utilized by veterinarians. The literature regarding the interaction of biologic therapies with other therapeutics is still in its infancy. Initial studies have examined the effects of exercise, stress, various pharmaceutical interventions, extracorporeal shockwave, therapeutic laser, and hyperbaric oxygen on biologic therapies. Continued research is imperative as owners and veterinarians increasingly choose a multimodal approach to injury and illness. Further, understanding the effects of concurrently administered treatments and pharmaceuticals as well as the health status of the horse is imperative to providing the optimal therapeutic outcome.

Localized pollution of veterinary antibiotics in watersheds receiving treated effluents from swine farms

Swine excrement is discharged into surface waters mainly as effluent in Asian countries. As swine production consumes more antibiotics and less water than humans, a mismatch of the size of swine farms and that of the rivers receiving their effluent could create severe pollution by antibiotics. However, little is known about the occurrence of antibiotics in such rivers. We therefore monitored seven veterinary drugs, six human drugs (including a metabolite), three drugs for both use (including a metabolite), and major water qualities at 30 sites in Japanese watersheds where swine outnumber humans and where their excrement is largely treated on-site by aerobic biological wastewater processes. The compositions of veterinary drugs differed substantially among sites, unlike human drugs, indicating various patterns of use among swine farms. Median concentrations at the 30 sites were <1 ng/L for seven out of the ten drugs used in livestock, whereas maximum concentrations were >1000 ng/L for three and 100-1000 ng/L for four of them, giving median-maximum among the sites of >3 log for two and 2-3 log for six of them. The spatial distribution ranges of concentrations of veterinary drugs were wider than those of human drugs (mostly <1.5 log) and other analytes (mostly <1 log), despite the correlation between those of total veterinary drugs and nitrogen, attributable to fewer swine farms than households, the intensive animal husbandry, and the various drug-use patterns among the farms. The range of maximum concentrations of veterinary drugs in the watersheds was comparable to those reported in other Asian watersheds with less strict management of swine excrement, attributable to their slow decay in conventional wastewater treatment on swine farms. Thus, attention should be paid to hot-spot pollution of antibiotics on large Asian swine farms adjacent to streams with limited dilution capacity.

A 4-year study of bovine reproductive hormones that are induced by pharmaceuticals and appear as steroid estrogenic pollutants in the resulting slurry, using in vitro and instrumental analytical methods

The main objective of the research was to study the environmental "price" of the large-scale, milk production from a rarely known perspective, from the mapping of the estrogenic footprint (the amount of oestrus-inducer hormonal products, and the generated endoestrogens) in the resulting slurry in a dairy cow farm. These micropollutants are endocrine-disrupting chemicals (EDCs) and can be dangerous to the normal reproductive functions even at ng/kg concentration. One of them, 17ß-estradiol, has a 20,000 times stronger estrogenic effect than bisphenol-A, a widely known EDC of industrial origin. While most studies on EDCs are short-term and/or laboratory based, this study is longitudinal and field-based. We sampled the slurry pool on a quarterly basis between 2017 and 2020. Our purpose was testing the estrogenic effects using a dual approach. As an effect-based, holistic method, we developed and used the YES (yeast estrogen screen) test employing the genetically modified Saccharomyces cerevisiae BJ3505 strain which contains human estrogenic receptor. For testing exact molecules, UHPLC-FLD was used. Our study points out that slurry contains a growing amount of EDCs with the risk of penetrating into the soil, crops and the food chain. Considering the Green Chemistry concept, the most benign ways to prevent of the pollution of the slurry is choosing appropriate oestrus-inducing veterinary pharmaceuticals (OIVPs) and the separation of the solid and liquid parts with adequate treatment methods. To our knowledge, this is the first paper on the adaptation of the YES test for medicine and slurry samples, extending its applicability. The adapted YES test turned out to be a sensitive, robust and reliable method for testing samples with potential estrogenic effect. Our dual approach was successful in evaluating the estrogenic effect of the slurry samples.

Anthelminthic Veterinary Medicines Interactions with the Soil Microbiota

Anthelminthics (AHs) are used to control gastrointestinal nematodes (GINs) in productive animals. They are rapidly excreted by animals, ending up in soil through direct deposition of animal dung or application of animal excreta as manures. Most environmental research on AHs has focused on their toxicity to aquatic organisms and soil fauna while their interactions with the soil microbiota, a key component of a functioning soil ecosystem, have been overlooked. In this article, we summarize current knowledge on the interactions of Ahs with the soil (micro) biota, we highlight recent evidence for the toxicity of AHs on soil microorganisms and discuss those results in the frame of the current environmental risk assessment (ERA) of veterinary medicines.

Call for solutions to veterinary medicines supply issues in Northern Ireland

Anna Judson called for a resolution to the issue of access to veterinary medicines in Northern Ireland during her first major speech as the new BVA President at our annual Northern Ireland dinner.

Composting post-anaerobic digestion for emerging contaminant biodegradation: Impacts of operating conditions

Sustainable manure management technologies are needed, and combining anaerobic digestion (AD) for energy generation and aerobic composting (AC) to stabilize digestate and remove emerging contaminants (ECs), including veterinary pharmaceuticals and steroid hormones, is promising. This study identified post-AD, AC operating conditions that maximized degradation of study ECs, expected to be present in cattle manure digested using treated municipal wastewater as the water source. Study ECs included sulfamethoxazole (SMX), chlortetracycline (CTC), oxytetracycline (OTC), estrone (E1), and naproxen (NPX). Composting conditions were simulated in bench-scale reactors, with microorganisms from digestate produced in an AD system (25L scale), by varying temperatures, pH, and carbon source compositions (representing food waste/manure co-digestion with different residence times). Results indicate maximum SMX biodegradation occurred at 35°C, pH 7, and with high levels of easily degradable carbon (≥99%, 99%, and 98%), and maximum E1 biodegradation occurred at 35°C, and with low levels of easily degradable carbon (≥97% and 99%). Abiotic degradation was responsible for the nearly complete removal of tetracyclines under all conditions and for partial degradation of NPX (between 20% and 48%). Microorganisms originating from the AD system putatively capable of SMX and E1 biodegradation, or of contributing to biodegradation during the AC phase, were identified, including phylotypes previously shown to biodegrade SMX (Brevundimonas and Alcaligenes).

The Role of Personalized Medicine in Companion Animal Cardiology

Cardiomyopathies remain one of the most common inherited cardiac diseases in both human and veterinary patients. To date, well over 100 mutated genes are known to cause cardiomyopathies in humans with only a handful known in cats and dogs. This review highlights the need and use of personalized one-health approaches to cardiovascular case management and advancement in pharmacogenetic-based therapy in veterinary medicine. Personalized medicine holds promise in understanding the molecular basis of disease and ultimately will unlock the next generation of targeted novel pharmaceuticals and aid in the reversal of detrimental effects at a molecular level.

Veterinary pharmaceutical as emerging contaminants in wastewater and surface water: An overview

Veterinary pharmaceuticals have become of interest due to their indiscriminate use. Thus, this paper compiles studies on detection in surface and wastewater, and the treatment applied for their removal. Additionally, a case study was performed to evaluate its commercialization, as the ecological risk assessment for the most relevant compounds. 241 compounds were detected. The highest concentrations were found for antibiotics such as oxytetracycline, amoxicillin, and monensin, with values up to 3732.4 µg/L. Biological treatments have been mainly reported, obtaining removal greater than 80% for sulfadiazine, sulfamethazine, sulfamethoxazole, enrofloxacin, and oxytetracycline. Considering the case study, enrofloxacin and oxytetracycline were widely commercialized. Finally, there was a low risk for the species exposed to enrofloxacin, in contrast, the species exposed to oxytetracycline presented a high risk of long-term mortality. Concluding that veterinary compounds have emerged as a significant concern regarding water source contamination, owing to their potential adverse effects on aquatic biota and even human. This is particularly relevant because many water bodies that receive wastewater are utilized for drinking water purposes. Consequently, the development of comprehensive, full-scale systems for efficient antibiotic removal before their introduction into water sources becomes imperative. Equally important is the need to reconsider their extensive use altogether.

Developing a career…versus careering through your professional life

Vet Jeremy Johnson's career journey went from large animal 'grunt', through a world of pharmaceuticals, to embracing consultancy and then becoming director of new SQP training and registration body Vetpol.

Multi-class/residue method for determination of veterinary drug residues, mycotoxins and pesticide in urine using LC-MS/MS technique

BACKGROUND

Veterinary drugs are widely used in animals to prevent diseases and are a complex set of drugs with very different chemical properties. Multiclass and multi-residue methods for simultaneous detection of residues from veterinary drugs and contaminants in urine are very rare or non-existent. Therefore, the aim of this study was to develop and validate a sensitive and reliable quantitative LC-MS/MS method for simultaneous determination of a wide range of veterinary drug and pesticide residues and mycotoxins in bovine urine. This involved 42 veterinary drug residues (4 thyreostats, 6 anabolic hormones, 2 lactones, 10 beta agonists, 15 antibiotics, 5 sulphonamides), 28 pesticides and 2 mycotoxins. Stable isotopically labelled internal standards were used to facilitate effective quantification of the analytes. Analysis was performed in both positive and negative ionization modes with multiple reaction monitoring transitions over a period of 12 min.

RESULTS

The parameters validated included linearity, limit of detection (LOD), limit of quantification (LOQ), detection capability (CCβ), decision limit (CCα), stability, accuracy and precision. The process followed guidelines of the regulation 2021/808/EC. The calibration curves were linear with coefficient of correlation (R2) from 0.991 to 0.999. The LODs were from 0.01 to 2.71 µg/L, while the LOQs were from 0.05 to 7.52 µg/L. The CCα and CCβ were in range 0.05-12.11 µg/L and 0.08-15.16 µg/L. In addition, the average recoveries of the spiked urine samples were from 71.0 to 117.0% and coefficient of variation (CV) < 21.38% (intraday and interday).

CONCLUSION

A new isotopic LC-MS/MS method has been developed, validated and applied for identification and quantification of 72 residues of veterinary drugs and pesticides and other contaminants such as mycotoxins in bovine urine. The most appropriated sample preparation procedures involved sodium acetate buffer, enzymatic hydrolysis using β-glucuronidase and cleanup solid phase extraction with OASIS SPE cartridges. The parameters were satisfactorily validated fulfilling requirements under Regulation 2021/808/EC. Consequently, the method could be used in routine analysis of bovine urine samples for simultaneous detection of veterinary drug and pesticide residues as well as contaminants such as mycotoxins.

Use of cutting-edge RNA-sequencing technology to identify biomarkers and potential therapeutic targets in canine and feline cancers and other diseases

With the growing interest in companion animals and the rapidly expanding animal healthcare and pharmaceuticals market worldwide. With the advancements in RNA-sequencing (RNA-seq) technology, it has become a valuable tool for understanding biological processes in companion animals and has multiple applications in animal healthcare. Historically, veterinary diagnoses and treatments relied solely on clinical symptoms and drugs used in human diseases. However, RNA-seq has emerged as an effective technology for studying companion animals, providing insights into their genetic information. The sequencing technology has revealed that not only messenger RNAs (mRNAs) but also non-coding RNAs (ncRNAs) such as long ncRNAs and microRNAs can serve as biomarkers. Based on the examination of RNA-seq applications in veterinary medicine, particularly in dogs and cats, this review concludes that RNA-seq has significant potential as a diagnostic and research tool. It has enabled the identification of potential biomarkers for cancer and other diseases in companion animals. Further research and development are required to maximize the utilization of RNA-seq for improved disease diagnosis and therapeutic targeting in companion animals.

Development of machine learning algorithms to estimate maximum residue limits for veterinary medicines

Establishing maximum-residue limits (MRLs) for veterinary medicine helps to protect the human food supply. Guidelines for establishing MRLs are outlined by regulatory authorities that drug sponsors follow in each country. During the drug approval process, residue limits are targeted for specific animal species and matrices. Therefore, MRLs are commonly not established for other species. This study demonstrates unestablished MRLs can be reliably predicted for under-represented food commodity groups using machine learning (ML). Classification methods with imbalanced data were used to analyze MRL data from multiple countries by implementing resampling techniques in different ML classifiers. Afterward, we developed and evaluated a data-mining method for predicting unestablished MRLs. Seven different ML classifiers such as support vector classifier, multi-layer perceptron (MLP), random forest, decision tree, k-neighbors, Gaussian NB, and AdaBoost have been selected in this baseline study. Among these, the neural network MLP classifier reliably scored the highest average-weighted F1 score (accuracy >99% with markers and ≈88% without markets) in predicting unestablished MRLs. This provides the first study to apply ML algorithms in regulatory food animal medicine. By predicting and estimating MRLs, we can potentially decrease the use and cost of live animals and the overall research burden of determining new MRLs.

Animal board invited review: Quantification of resilience in farm animals

Resilience, when defined as the capacity of an animal to respond to short-term environmental challenges and to return to the prechallenge status, is a dynamic and complex trait. Resilient animals can reinforce the capacity of the herd to cope with often fluctuating and unpredictable environmental conditions. The ability of modern technologies to simultaneously record multiple performance measures of individual animals over time is a huge step forward to evaluate the resilience of farm animals. However, resilience is not directly measurable and requires mathematical models with biologically meaningful parameters to obtain quantitative resilience indicators. Furthermore, interpretive models may also be needed to determine the periods of perturbation as perceived by the animal. These applications do not require explicit knowledge of the origin of the perturbations and are developed based on real-time information obtained in the data during and outside the perturbation period. The main objective of this paper was to review and illustrate with examples, different modelling approaches applied to this new generation of data (i.e., with high-frequency recording) to detect and quantify animal responses to perturbations. Case studies were developed to illustrate alternative approaches to real-time and post-treatment of data. In addition, perspectives on the use of hybrid models for better understanding and predicting animal resilience are presented. Quantification of resilience at the individual level makes possible the inclusion of this trait into future breeding programmes. This would allow improvement of the capacity of animals to adapt to a changing environment, and therefore potentially reduce the impact of disease and other environmental stressors on animal welfare. Moreover, such quantification allows the farmer to tailor the management strategy to help individual animals to cope with the perturbation, hence reducing the use of pharmaceuticals, and decreasing the level of pain of the animal.

Antibiograms as one-health tools for antimicrobial stewardship: California's experience with livestock antibiogram development

Antibiograms are collections of antimicrobial susceptibility data for a particular bacterial organism and host species. Antibiograms are important tools for antimicrobial stewardship, as they may be used to guide empiric antimicrobial therapy and assess trends in antimicrobial resistance, maximizing treatment success and preserving the efficacy of currently available pharmaceuticals. Targeted use of antimicrobials is critically important to minimize the spread of antimicrobial resistance, which may be conveyed between animals and humans directly but may also be spread through the environment and ecological niches, such as soil, water, and wildlife reservoirs. To effectively utilize antibiograms as part of a comprehensive antimicrobial stewardship plan, veterinarians need to know data characteristics, including the source population, body site (when possible), and number of isolates included, in addition to the animal species and bacterial organisms for which each breakpoint was developed. Although widely used in human health systems, antibiograms are not often available in veterinary medicine. This paper describes antibiogram creation and use, discusses antibiogram development by US veterinary diagnostic laboratories, and shares California's process to create and promote livestock antibiograms. The companion Currents in One Health article by Burbick et al, AJVR, September 2023, addresses the benefits and challenges associated with developing veterinary antibiograms.

Target and non-target analytical method for potential hazardous substances in livestock and pet hair using liquid- and gas chromatography quadrupole time-of-flight mass spectrometry

Extraction using acetonitrile and water and quadrupole time-of-flight mass spectrometry (LC and GC-QTOF/MS) techniques were used to screen for potential hazardous substances in livestock and pet hair. In addition, LC-MS/MS and GC-MS/MS techniques were used for verification of the analytical method and quantitative analysis of pesticides, veterinary drugs, mycotoxins and antioxidants in hair. Optimized sample preparation involves extracting 0.05 g of sample with 0.6 mL of ACN and 0.4 mL of distilled water. In addition, the two layers were separated by adding 0.1 g of NaCl. Then, both the ACN and water layers were analyzed by LC-TOF/MS, and the ACN layer was analyzed by GC-TOF/MS. Most of the matrix effects of livestock and pet hair were less than 50%, but some matrices and components showed high results, so matrix matching correction was applied for more precise quantification. Method validation was performed for 394 constituents (293 pesticides, 93 veterinary drugs, 6 mycotoxins and 2 preservatives) in dog, cat, cow and pig hair and chicken and duck feathers. All components showed good linearity (r2 ≥0.98) in the developed assay. The quantification limit of all compounds was set at 0.02 mg/kg, which is the lowest level that satisfies the recovery rate standard. The recovery experiment was repeated 8 times at 3 concentrations. Most of the components were extracted with the ACN layer, and the recovery rate was 63.35-119.98%. In order to confirm the efficiency of extracting harmful substances from actual samples, 30 hairs of livestock and pets were screened.

Influence of manure application method on veterinary medicine losses to water

Veterinary medicines are routinely used within modern animal husbandry, which results in frequent detections within animal manures and slurries. The application of manures to land as a form of organic fertiliser presents a pathway by which these bioactive chemicals can enter the environment. However, to date, there is limited understanding regarding the influence of commonly used manure application methods on veterinary medicine fate in soil systems. To bridge this knowledge gap, a semi-field study was conducted to assess the influence of commonly used application methods such as, broadcast, chisel sweep, and incorporation on veterinary medicine losses to waters. A range of veterinary medicines were selected and applied as a mixture; these were enrofloxacin, florfenicol, lincomycin, meloxicam, oxytetracycline, sulfadiazine, trimethoprim and tylosin. All the assessed veterinary medicines were detected within surface runoff and leachates, and the concentrations generally decreased throughout the irrigation period. The surface runoff concentrations ranged from 0.49 to 183.47 μg/L and 2.26-236.83 μg/L for the bare soil and grass assessments respectively. The leachate concentrations ranged from 0.04 to 309.66 μg/L and 0.33-37.79 μg/L for the bare soil and grass assessments respectively. More advanced application methods (chisel sweep) were found to significantly reduce the mass loads of veterinary medicines transported to surface runoff and leachate by 13-56% and 49-88% over that of broadcast. Incorporating pig slurries reduced the losses further with surface runoff and leachate losses being 13-56% and 49-88% lower than broadcast. Our results show that manure application techniques have a significant effect on veterinary medicine fate in the environment and as such these effects should be considered in the decision-making processes for the management of manures as well as from a risk mitigation perspective for aquatic compartments.

Introduction of multilayered magnetic core-dual shell SERS tags into lateral flow immunoassay: A highly stable and sensitive method for the simultaneous detection of multiple veterinary drugs in complex samples

Direct, convenient, and sensitive monitoring of the residues of multiple drugs in complex environments is important but remains a challenge. Here, we report a surface-enhanced Raman scattering (SERS)-based multiplexed lateral flow immunoassay (LFA) that supports the simultaneous and sensitive detection of commonly used drugs kanamycin, ractopamine, clenbuterol, and chloramphenicol in unprocessed complex samples through the dual signal amplification strategy of numerous efficient hotspots and magnetic enrichment. Multilayered magnetic-core dual-shell nanoparticles (MDAu@Ag) with controllable subtle nanogaps were fabricated via the polyethyleneimine-mediated layer-by-layer (LBL) assembly of two layers of Au@Ag satellites onto superparamagnetic Fe₃O₄ cores and conjugated with specific antibodies as multifunctional tags in the LFA system for rapid capture, separation, and quantitative analysis. Two Raman reporters were embedded in internal nanogaps and modified on the surface of MDAu@Ag for the simultaneous and ultrasensitive detection of four targets on two test lines, which greatly simplified the fabrication and signal reading of SERS-LFA. The proposed assay can rapidly detect multiple drug residues in 35 min with detection limits down to pg/mL level. Moreover, the MDAu@Ag-based SERS-LFA demonstrated better stability, higher throughput, and superior sensitivity (at least 400 times) than traditional colloidal gold immunochromatography, showing its great potential in the field of point-of-care testing.

Spatiotemporal distribution of veterinary and human drugs and its predictability in Japanese catchments

Little is known about the predictability of mass flows of veterinary drugs in Asian catchments, where effluent from livestock farms is a major source. We therefore conducted this study to understand the applicability and limitations of a population-based emission model, which assumed usage of veterinary and human drugs to be evenly distributed over the national livestock or human population throughout the year, and sources to be effluent discharges at livestock farms, households, and sewage treatment plants in Japanese catchments. We monitored five veterinary drugs (lincomycin, sulfamonomethoxine, tiamulin, tylosin, and tilmicosin), two human and livestock drugs (sulfamethoxazole and trimethoprim), two human drugs (carbamazepine and clarithromycin), and a metabolite (sulfapyridine) of a human drug once a month over 2 years in eight Japanese rivers which have active livestock farming in their catchments. Mass flows of carbamazepine and sulfapyridine were stable, while those of veterinary drugs fluctuated widely, especially sulfamonomethoxine and tilmicosin, whose 25 %-100 % ranges averaged 1.5 and 1.2 log units, respectively, attributable mainly to their usage patterns. The model accurately predicted mean mass flows of carbamazepine in the rivers with errors of <±0.3 log unit. Although it slightly to moderately overestimated those of the other four human-related compounds, the incorporation of an empirical correction factor, determined to minimize mean absolute error (MAE) among the rivers, substantially lowered their MAEs to <0.23 log units. However, the MAEs of the five veterinary drugs were as high as 0.42 (sulfamonomethoxine) to 0.60 (tiamulin) log units even with the coefficient, likely due mainly to the spatial distribution of their usage per capita. So as not to overlook spatiotemporal elevation of risks of veterinary drugs, a stochastic method should be applied in their management. This is the first study to assess the use of spatiotemporal homogeneity in usage per capita of veterinary drugs in Asian catchments.

RNA viruses alter house dust mite physiology and allergen production with no detected consequences for allergenicity

RNA viruses have recently been detected in association with house dust mites, including laboratory cultures, dust samples, and mite-derived pharmaceuticals used for allergy diagnosis. This study aimed to assess the incidence of viral infection on Dermatophagoides pteronyssinus physiology and on the allergenic performance of extracts derived from its culture. Transcriptional changes between genetically identical control and virus-infected mite colonies were analysed by RNAseq with the support of a new D. pteronyssinus high-quality annotated genome (56.8 Mb, 108 scaffolds, N50 = 2.73 Mb, 96.7% BUSCO-completeness). Extracts of cultures and bodies from both colonies were compared by inspecting major allergen accumulation by enzyme-linked immunosorbent assay (ELISA), allergen-related enzymatic activities by specific assays, airway inflammation in a mouse model of allergic asthma, and binding to allergic patient's sera IgE by ImmunoCAP. Viral infection induced a significant transcriptional response, including several immunity and stress-response genes, and affected the expression of seven allergens, putative isoallergens and allergen orthologs. Major allergens were unaffected except for Der p 23 that was upregulated, increasing ELISA titers up to 29% in infected-mite extracts. By contrast, serine protease allergens Der p 3, 6 and 9 were downregulated, being trypsin and chymotrypsin enzymatic activities reduced up to 21% in extracts. None of the parameters analysed in our mouse model, nor binding to human IgE were significantly different when comparing control and infected-mite extracts. Despite the described physiological impact of viral infection on the mites, no significant consequences for the allergenicity of derived extracts or their practical use in allergy diagnosis have been detected.

Residues of an anthelmintic veterinary drug (closantel) detected in red foxes (Vulpes vulpes) in Scotland

The contamination of the environment by some veterinary medicines and their impact on wild animals is of increasing concern. However, there is a lack of information about their residues in wildlife. The sentinel animals most commonly used for monitoring the level of environmental contamination are birds of prey, and information on other carnivores and scavengers scarce. This study examined the livers from 118 foxes for residues of a range of 18 veterinary medicines (16 anthelmintic agents and 2 metabolites) used on farm livestock. The samples were collected from foxes, primarily in Scotland, shot during legal pest control activities conducted between 2014 and 2019. Closantel residues were detected in 18 samples, and the concentrations found ranged from 6.5 µgkg^-1 to 1383 µgkg^-1. No other compounds were found in significant quantities. The results show a surprising frequency and level of closantel contamination, raising concerns about both the route of contamination and the potential impacts on wild animals and the environment, such as the potential for significant wildlife contamination to contribute to the development of closantel-resistant parasites. The results also suggest that red fox (Vulpes vulpes) could be a useful sentinel species for detecting and monitoring some veterinary medicine residues in the environment.

An analytical framework on the leaching potential of veterinary pharmaceuticals: A case study for the Netherlands

Veterinary pharmaceuticals (VPs) residues may end up on the soil via manure, and from there can be transported to groundwater due to leaching. In this study an analytical framework to estimate the leaching potential of VPs at the national scale is presented. This approach takes soil-applied VPs concentrations, soil-hydraulic and soil-chemical properties, groundwater levels, sorption and degradation of VPs into account. For six commonly soil-applied VPs in the Netherlands, we assess quantities leached to groundwater and their spatial distribution, as well as the relative importance of processes that drive leaching. Our results for VPs Oxytetracycline, Doxycycline, and Ivermectin indicate that maximum quantities that may leach to groundwater are very low, i.e. ≪1 μg/ha, hence spatial differences are not investigated. For VPs Sulfadiazine and Flubendazole we identify a few regions that are potentially prone to leaching, with leached quantities higher than 1 μg/ha. Leaching patterns of these two VPs are dominated by soil properties and groundwater levels rather than soil-applied quantities. For Dexamethasone, even though applied on the soil in much lower concentrations compared to other investigated VPs, spatially widespread leaching to groundwater is found, with leached quantities higher than 1 μg/ha. Due to the leaching affinity of Dexamethasone, variations in the soil-applied amounts have significant influence on the quantities leached to groundwater. Dexamethasone is highlighted as important for the future environmental risk assessment efforts. This study has shown that the leaching potential of VPs is not determined by one single parameter, but by a combination of parameters. This combination also depends on the compound investigated.

Pet dogs transfer veterinary medicines to the environment

Worldwide, the number of pet dogs increases yearly, and as a result so does the use of veterinary medicines for flea and tick control. We investigated the potential transfer of veterinary flea products from dogs to the environment in a 'proof of principle' experiment. For this purpose, samples of hair, urine, and water after swimming were investigated. Nine dogs were recruited for this study, eight of which had been recently treated with an ectoparasiticide product. Hair and urine samples were tested for afoxalaner, fluralaner, fipronil and imidacloprid. Interestingly, contamination with ectoparasiticides was frequently demonstrated in samples from dogs untreated with these particular substances, suggesting widespread secondary transfer. In addition, hair retrieved from a bird's nest contained fipronil, fluralaner and imidacloprid, indicating a potential pathway for the exposure of juvenile birds. Three of the dogs also participated in a swimming experiment. One had been treated with oral fluralaner, whilst the remaining two had received other compounds not included in our study. However, in all three dogs, both fluralaner and imidacloprid were detected in hair samples. Fluralaner concentrations in the swimming water exceeded Dutch water quality standards, indicating a potential risk to the aquatic environment. Imidacloprid levels increased after each swimming dog, but did not breach Dutch water quality standard levels. These findings all call for improvements in the current risk assessment and management for veterinary medicines, by including companion animals and their exposure pathways into ecosystems.

Widespread Dissemination of Plasmid-Mediated Tigecycline Resistance Gene tet(X4) in Enterobacterales of Porcine Origin

The emergence of the plasmid-mediated high levels of the tigecycline resistance gene has drawn worldwide attention and has posed a major threat to public health. In this study, we investigated the prevalence of the tet(X4)-positive Enterobacterales isolates collected from a pig slaughterhouse and farms. A total of 101 tigecycline resistance strains were isolated from 353 samples via a medium with tigecycline, of which 33 carried tet(X4) (9.35%, 33/353) and 2 carried tet(X6) (0.57%, 2/353). These strains belong to seven different species, with Escherichia coli being the main host bacteria. Importantly, this report is the first one to demonstrate that tet(X4) was observed in Morganella morganii. Whole-genome sequencing results revealed that tet(X4)-positive bacteria can coexist with other resistance genes, such as blaNDM-1 and cfr. Additionally, we were the first to report that tet(X4) and blaNDM-1 coexist in a Klebsiella quasipneumoniae strain. The phylogenetic tree of 533 tet(X4)-positive E. coli strains was constructed using 509 strains from the NCBI genome assembly database and 24 strains from this study, which arose from 8 sources and belonged to 135 sequence types (STs) worldwide. We used Nanopore sequencing to interpret the selected 21 nonclonal and representative strains and observed that 19 tet(X4)-harboring plasmids were classified into 8 replicon types, and 2 tet(X6) genes were located on integrating conjugative elements. A total of 68.42% of plasmids carrying tet(X4) were transferred successfully with a conjugation frequency of 10-2 to 10-7. These findings highlight that diverse plasmids drive the widespread dissemination of the tigecycline resistance gene tet(X4) in Enterobacterales of porcine origin. IMPORTANCE Tigecycline is considered to be the last resort of defense against diseases caused by broad-spectrum resistant Gram-negative bacteria. In this study, we systematically analyzed the prevalence and genetic environments of the resistance gene tet(X4) in a pig slaughterhouse and farms and the evolutionary relationship of 533 tet(X4)-positive Escherichia coli strains, including 509 tet(X4)-positive E. coli strains selected from the 27,802 assembled genomes of E. coli from the NCBI between 2002 and 2022. The drug resistance of tigecycline is widely prevalent in pig farms where tetracycline is used as a veterinary drug. This prevalence suggests that pigs are a large reservoir of tet(X4) and that tet(X4) can spread horizontally through the food chain via mobile genetic elements. Furthermore, tetracycline resistance may drive tigecycline resistance through some mechanisms. Therefore, it is important to monitor tigecycline resistance, develop effective control measures, and focus on tetracycline use in the pig farms.

Characterizing Antimicrobial Resistance in Clinically Relevant Bacteria Isolated at the Human/Animal/Environment Interface Using Whole-Genome Sequencing in Austria

Antimicrobial resistance (AMR) is a public health issue attributed to the misuse of antibiotics in human and veterinary medicine. Since AMR surveillance requires a One Health approach, we sampled nine interconnected compartments at a hydrological open-air lab (HOAL) in Austria to obtain six bacterial species included in the WHO priority list of antibiotic-resistant bacteria (ARB). Whole genome sequencing-based typing included core genome multilocus sequence typing (cgMLST). Genetic and phenotypic characterization of AMR was performed for all isolates. Eighty-nine clinically-relevant bacteria were obtained from eight compartments including 49 E. coli, 27 E. faecalis, 7 K. pneumoniae and 6 E. faecium. Clusters of isolates from the same species obtained in different sample collection dates were detected. Of the isolates, 29.2% were resistant to at least one antimicrobial. E. coli and E. faecalis isolates from different compartments had acquired antimicrobial resistance genes (ARGs) associated with veterinary drugs such as aminoglycosides and tetracyclines, some of which were carried in conjugative and mobilizable plasmids. Three multidrug resistant (MDR) E. coli isolates were found in samples from field drainage and wastewater. Early detection of ARGs and ARB in natural and farm-related environments can identify hotspots of AMR and help prevent its emergence and dissemination along the food/feed chain.

Does a Traceability System Help to Regulate Pig Farm Households' Veterinary Drug Use Behavior? Evidence from Pig Farms in China

In China, there is a renewed interest in traceability systems as an efficient tool to guarantee pork safety. One of the pathways through which a traceability system can benefit consumers is by easing information asymmetry. However, past literature on the traceability system in China pays more attention to theoretical analysis and less to empirical analysis. Using a large-scale survey of pig farms in China, we investigate the effects influencing farmers' participation in the traceability system. Findings show that a traceability system can influence the safety of pork indirectly through its impacts on farmers' production behaviors. Another important finding is that unsafe pork is a result of non-standard use of veterinary drugs, and the traceability system works well for farmers by pushing them to take stricter safety measurements.

Enabling forecasts of environmental exposure to chemicals in European agriculture under global change

European agricultural development in the 21st century will be affected by a host of global changes, including climate change, changes in agricultural technologies and practices, and a shift towards a circular economy. The type and quantity of chemicals used, emitted, and cycled through agricultural systems in Europe will change, driven by shifts in the use patterns of pesticides, veterinary pharmaceuticals, reclaimed wastewater used for irrigation, and biosolids. Climate change will also impact the chemical persistence, fate, and transport processes that dictate environmental exposure. Here, we review the literature to identify research that will enable scenario-based forecasting of environmental exposures to organic chemicals in European agriculture under global change. Enabling exposure forecasts requires understanding current and possible future 1.) emissions, 2.) persistence and transformation, and 3.) fate and transport of agricultural chemicals. We discuss current knowledge in these three areas, the impact global change drivers may have on them, and we identify knowledge and data gaps that must be overcome to enable predictive scenario-based forecasts of environmental exposure under global change. Key research gaps identified are: improved understanding of relationships between global change and chemical emissions in agricultural settings; better understanding of environment-microbe interactions in the context of chemical degradation under future conditions; and better methods for downscaling climate change-driven intense precipitation events for chemical fate and transport modelling. We introduce a set of narrative Agricultural Chemical Exposure (ACE) scenarios - augmenting the IPCC's Shared Socio-economic Pathways (SSPs) - as a framework for forecasting chemical exposure in European agriculture. The proposed ACE scenarios cover a plausible range of optimistic to pessimistic 21st century development pathways. Filling the knowledge and data gaps identified within this study and using the ACE scenario approach for chemical exposure forecasting will support stakeholder planning and regulatory intervention strategies to ensure European agricultural practices develop in a sustainable manner.

First national survey of residues of active substances in honeybee apiaries across Spain between 2012 and 2016

This nationwide monitoring aimed to investigate the prevalence of residues of plant protection products (PPPs) and veterinary medicine products (VMPs) based on random selection of apiaries of Apis mellifera. For a three-year period (2012, 2013 and 2016), this study targeted 306 PPPs, VMPs and other active substances in 442 samples of bee bread honeycomb (BBHC) and 89 samples of honeybees collected from up to 177 apiaries. The results indicate that honeybees were most often exposed to residues of coumaphos, tau-fluvalinate, chlorfenvinphos, and acrinathrin, with a prevalence from a maximum of 98.8% to 49.4% in BBHC samples. Residues of coumaphos, tau-fluvalinate, amitraz (DMF + DMPF), carbendazim and orthophenylphenol were also frequently detected, from a maximum of 55.1% to 13.5% of the honeybee samples. Neonicotinoid residues, namely clothianidin and thiamethoxam, whose outdoor uses in crops are completely banned in EU, were not detected. Imidacloprid was found in 3.4% to 13.3% of samples during 2013 and 2016, respectively. Imidacloprid exceeded its acute toxicity (LD₅₀) value for honey bees in two samples of BBHC. Fipronil was detected in 0.5% of the samples during 2013. The diversity of active substances found (% of different residues analyzed) ranged from 33.9% to 37.2% in BBHC from 2012, 2013 to 2016, and was of 26.5% in honeybees in 2016. In at least 54% of the samples, the total residue load was in the range of 200 to 1500 μg·kg^-1. Up to 50% of BBHC samples were positive for one or two residues. No toxic residues for honeybees were detected in up to 88.8% of bee samples. This systematic surveillance of active substances assisted the evaluation of which target pesticides to look for and provided support to the competent authorities in the bee health decision-making.

Analysis of pesticides, veterinary drugs, and environmental contaminants in goat and lamb by the QuEChERSER mega-method

Analysis of chemical residues in foods is a big challenge for developing countries due to lack of financial and professional resources needed to meet international quality standards for trade. However, the implementation of simple multiclass, multi-residue methods in monitoring programs can provide significant benefits to save cost, time, and labor. The aim of this project was to investigate the "quick, easy, cheap, effective, rugged, safe, efficient, and robust" (QuEChERSER) mega-method for the fatty muscle matrices of goat and lamb. To achieve wide analytical scope covering pesticides, environmental contaminants, and veterinary drugs, extracts were analyzed by both ultrahigh-performance liquid and low-pressure gas chromatography (UHPLC and LPGC) coupled with tandem mass spectrometry (MS/MS). The QuEChERSER mega-method was validated in ovine (goat) and caprine (lamb) muscles at four different spiking levels with 10 replicates per level for a total of 330 analytes and metabolites, consisting of 225 pesticides, 89 veterinary drugs, and 16 polychlorinated biphenyls (PCBs). In the case of LPGC-MS/MS (preceded by automated "instrument-top sample preparation"), 92% and 82% of the analytes met the data quality objectives of 70-120% recovery and <20% RSD for goat and lamb, respectively. For UHPLC-MS/MS, 95% and 92% of the analytes met the acceptable validation criteria in goat and lamb, respectively. Thus, the QuEChERSER mega-method has been demonstrated to be a useful streamlined approach to more efficiently replace multiple methods currently used to cover the same analytical scope.

Field safety experience with an autologous cancer vaccine in tumor-bearing cats: a retrospective study of 117 cases (2015-2020)

OBJECTIVES

The aim of this study was to determine the frequency and severity of adverse events (AEs) reported from use of an adjuvanted whole-cell autologous cancer vaccine in cats with solid tumors under field conditions.

METHODS

The case accession database at Torigen Pharmaceuticals was searched to identify client-owned cats that underwent biopsy or surgical resection of their primary tumor, had histologic confirmation of neoplasia and received at least one subcutaneous dose of an adjuvanted whole-cell autologous cancer vaccine. Records were reviewed for any reported AEs.

RESULTS

In total, 117 cats met the inclusion criteria and received 422 doses of autologous cancer vaccine. Six (5.1%) cats had seven reported AEs, with the majority of these (85.7%) being characterized as grade 1 or 2 (mild) and resolving without medical intervention.

CONCLUSIONS AND RELEVANCE

AEs were infrequent in cats treated with an adjuvanted whole-cell autologous cancer vaccine under typical field use conditions. This form of active cancer immunotherapy appears to be well tolerated by cats and may represent a treatment option for owners who are concerned about AEs associated with chemotherapy or radiotherapy. Additional studies are warranted to determine the efficacy of this form of individualized immunotherapy in cats with solid tumors.

[New drugs for small animals in 2021]

In 2021, 8 novel pharmaceutical agents for small animals were released on the German market: The specific monoclonal antibodies bedinvetmab (Librela^®) and frunevetmab (Solensia^®), the cyclooxygenase-2 inhibitor enflioxib (Daxocox^®), the ectoparasitic esafoxolaner (NexGard^® Combo) of the isoxazoline group, the anti-haemorrhagic etamsylate (Hemosilate), the antidepressant mirtazapine (Mirataz^®), the alpha-selective sympathomimetic tetryzoline for ophthalmic use (Zolicep^®) and the cytostatic tigilanol tiglate (Stelfonta^®). No active substance received an animal species extension. In addition, for small animals, there were new releases of two agents in a novel pharmaceutical formulation (cefalexin, gentamicin), five drugs with a new content of the active ingredient (metronidazole, pimobendan, thiamazole, tramadol, trilostane), one veterinary drug with a new combination of active ingredients (lotilaner + milbemycin oxime), one drug with a new route of administration (propofol) and furthermore two temporarily non-available active ingredients for certain animal species were reapproved in new drugs (levothyroxine for cats and oxytetracycline for dogs and cats).

The effect of anaerobic pig slurry redox potentials on the degradation of veterinary medicines

Veterinary medicines are frequently used within intensive livestock husbandry and there has been a growing interest regarding their fate in the environment. However, research has seldom assessed the influence of pig slurry properties on the fate of veterinary medicines even though such an understanding is essential for a more robust environmental risk assessment. Changes within manure degradation rates have the potential to alter the concentration of antibiotics applied to land, and the outcome of the risk assessment. The aim of this work was to investigate whether commonly reported redox potentials affect the degradation rates of acetyl-salicylic acid, ceftiofur, florfenicol, oxytetracycline, sulfamethoxazole, and tylosin. The employed redox potentials were -100 mV (reduced), -250 mV (anaerobic) and -400 mV (very anaerobic). A compound specific relationship was observed where the degradation of ceftiofur, florfenicol, oxytetracycline and sulfamethoxazole was inhibited under reduced conditions over that of very anaerobic; the respective DT50 values were 0.7-1.84 h, 1.35-3.61 h, 22.2-49.8 h, 131-211 h and 35.4-94 h. In contrast, tylosin was found to degrade faster at reduced conditions over very anaerobic (DT50 6.88-19.4 h). The presented research demonstrates the importance of redox potential on degradation rates and suggests we need stringent and harmonized redox control to improve the environmental risk assessment of veterinary medicines. Environmental relevance and significance: Given the significant effect of anaerobic redox potentials on veterinary medicine fate tighter regulation is required in manure degradation trials.

Strengthening Australia's Chemical Regulation

Humans are exposed to a myriad of chemicals every day, some of which have been established to have deleterious effects on human health. Regulatory frameworks play a vital role in safeguarding human health through the management of chemicals and their risks. For this review, we focused on agricultural and veterinary (Agvet) chemicals and industrial chemicals, which are regulated, respectively, by the Australian Pesticides and Veterinary Medicines Authority (APVMA), and the Australian Industrial Chemicals Introduction Scheme (AICIS). The current frameworks have been considered fragmented, inefficient, and most importantly, unsafe in prioritizing human health. We evaluated these frameworks, identified gaps, and suggested improvements that would help bring chemical regulation in Australia in line with comparative regulations in the EU, US, and Canada. Several weaknesses in the Australian frameworks include the lack of a national program to monitor chemical residues, slow pace in conducting chemical reviews, inconsistent risk management across states and territories, a paucity of research efforts on human health impacts, and inadequate framework assessment systems. Recommendations for Australia include establishing a national surveillance and chemical residue monitoring system, harmonizing risk assessment and management across jurisdictions, improving chemical review efficiency, and developing regular performance review mechanisms to ensure that human health is protected.