Cumulative veterinary drug and pesticide dietary exposure assessments: a global overview and Brazilian framework considerations.

Pesticides and veterinary drugs are widely employed to support food production. Assessing potential risks associated with the dietary consumption of pesticide and veterinary drug residues is, however, essential. Potential risks depend on the toxicity degree of the analyzed residue and population exposure levels. Human populations are exposed to numerous chemical substances through different pathways with varying exposure times, leading to increased health risks when compared to exposure to individual chemicals. Cumulative exposure assessments usually assess combined exposures to multiple chemicals through multiple exposure pathways. In this sense, this comprehensive review aims to provide insights into cumulative dietary pesticide and veterinary drug residue exposures. The main methodologies, strategies, and legislation employed by international agencies to this end are discussed. A review concerning articles that apply existing methodologies and approaches, as well as the challenges in this context faced by Brazil is also presented. As this is a critical issue not only for Brazilian public health but also for the global community, regulatory agencies should prioritize formulating regulations that incorporate exposure assessments regarding the simultaneous presence of residues and contaminants in foodstuffs.

A Cross-sectional Online Questionnaire-based Survey About the Use of Compounded Medications in Veterinary Ophthalmology.

The aims of this survey were to determine how veterinary ophthalmologists worldwide use compounded ophthalmic drugs to treat ocular diseases, define their attitudes regarding compounding pharmacies, and identify commonly dispensed veterinary ophthalmic formulations as well as the diseases for which those preparations are most often prescribed. Respondents voluntar i ly and anonymously completed a questionnaire that was sent to a total of 1014 veterinary ophthalmologists at universities, specialty colleges, and ophthalmology associations in 24 countries. One hundred thirty (12.83%) veterinary ophthalmologists replied. Of those, 87 (66.92%) had worked in  veterinary ophthalmology for more than 10 years. Ten to 30% of their total prescriptions were compounded ophthalmic drugs, the most common of which were tacrolimus and cyclosporine for the treatment of keratoconjunctivitis sicca. Reported advantages of treatment with a compound included the accessibility of preparations that were not commercially available and the ability to customize formulations; reported disadvantages included brief shelf life, delivery time, and cost.

Computational prediction of retention times of veterinary antibiotics obtained by liquid chromatography-mass spectrometry.

BACKGROUND: Veterinary antibiotics are chemical compounds used to kill or inhibit the growth of pathogenic bacteria associated with animal diseases. These molecules can be defined by their retention times (tR) in liquid chromatography-mass spectrometry (LC-MS). One strategy to predict the tR of new veterinary antibiotics is the development of predictive quantitative structure-property relationships (QSPRs), which were used in this study. RESULTS: A database of 122 antibiotics was selected in which the tR was measured using a Hypersil GOLD column. An optimal three-feature model was developed by integrating the unsupervised variable reduction, replacement method variable subset selection, and multiple linear regression. The negligible differences among the coefficient of determination and the root-mean-square error for the training set (R2 = 0.902 and RMSEC = 0.871) and test set (Q2 = 0.854 and RMSEP = 1.064) indicate a stable and predictive model. In a further step, a more in-depth explanation of the mechanism of action of each descriptor in predicting the tR is provided, with the construction of the theoretical chemical space for accurate predictions of new antibiotics. CONCLUSION: The in silico model developed in this work identified three molecular descriptors associated with aqueous solubility, octanol-water partition coefficient, and the presence of negative and lipophilic atom pairs. The QSPR developed here could be implemented by agricultural and food chemists to identify and monitor existing and new antibiotics within the framework of LC-MS. The computational model was developed in accordance with five principles outlined by the Organization for Economic Co-operation and Development. © 2024 Society of Chemical Industry.

An account of the occurrence of residues from veterinary drugs and contaminants in animal-derived products: a case study on Brazilian supply chains.

Brazil plays an important role in ensuring its position on the international market by assuring high food safety standards for its products, and all products should meet the requirements for residues from veterinary drugs and contaminants in animal products. Statutory monitoring provides insights into the compliance of the Brazilian industry regarding these legal requirements. The objective of this study was to provide insight into the safety of Brazilian animal products by reporting the occurrence of residues from veterinary drugs and contaminants according to an analysis of an 11-year report published by the Brazilian Ministry of Agriculture, Livestock and Food Supply (MAPA). Between 2010 and 2021, 166,647 samples from animal-derived products were analyzed in Brazil, and 624 of those samples were non-compliant (0.37%) exceeding maximum residue limits (>MRLs) or showed the presence of prohibited substances. The most common types of substances found in the non-compliant samples were heavy metals, parasiticides, and antimicrobials, accounting for 82% of all documents from the MAPA. Among Brazilian products, the challenge related to occurrence of substances varied across the food supply chain, with highest incidence rates observed in the fish chain, followed by eggs, milk, equids, sheep/goat, honey, bovine, swine, and broilers chains in decreasing order. Considering the type of substance, heavy metals were found to be more prevalent in fish products, mainly arsenic in wild fish. The prevalence of contaminants and heavy metals decreased, while that of veterinary drugs increased in Brazilian products from 2010 to 2021. From these results, it can be concluded that the number of accidental incidents including those associated with environmental contaminants decreased over the last decade, opposed to those involving human adversaries and deliberate illegal actions, such as the abuse of veterinary drugs, increased. Future monitoring plans need to take this paradigm shift into account.

Efficient removal of veterinary drugs from aqueous solutions using magnetically separable carbonaceous materials derived from cobalt and iron metal-organic frameworks.

Rapid synthesis of carbon-based magnetic materials derived from cobalt and iron metal-organic frameworks (MOFs), ZIF-67, and MIL-100(Fe), by microwave-assisted method, followed by carbonization under a N2 atmosphere is described in this study. The carbon-derived MOFs (CDMs) were evaluated for the removal of the emerging pollutants sulfadiazine (SDZ) and flumequine (FLU) used as veterinary drugs. The study aimed to link the adsorption behavior with their surface properties and elemental composition. C-ZIF-67 and C-MIL-100(Fe) showed hierarchical porous structures with specific surface areas of 295.6 and 163.4 m2 g-1, respectively. The Raman spectra of the CDMs show the characteristic D and G bands associated with defect-rich carbon and sp2 graphitic carbon, respectively. The CDMs exhibit cobalt species (Co3O4, CoO, and Co) in C-ZIF-67 and iron species (Fe2O3, Fe3O4, and Fe) in C-MIL-100 (Fe) which are related to the magnetic behavior of CDMs. C-ZIF-67 and C-MIL-100 (Fe) had saturation magnetization values of 22.9 and 53.7 emu g-1, respectively, allowing easy solid-liquid separation using a magnet. SDZ and FLU removal rates on CDMs follow pseudo-second-order kinetics, and adsorption isotherms fit the Langmuir model based on regression coefficient values. Adsorption thermodynamics calculations showed that the adsorption of SDZ and FLU by CDMs was a thermodynamically favorable process. Therefore, these properties of C-ZIF-67 and C-MIL-100 (Fe) and their regeneration ability facilitate their use as adsorbents for emerging pollutants.

Critical Evaluation of Two Qualitative Analytical Approaches for Multiclass Determination of Veterinary Drugs in Bovine Muscle Using UHPLC-Q-Orbitrap: The Wind of Change in Brazilian Monitoring.

Food safety is recognized as a main requirement for consumers, food industries, and official laboratories. Here, we present the optimization and screening qualitative validation of two multianalyte methods in bovine muscle tissues by ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry with an Orbitrap-type analyzer, operated with a heated ionization source in positive and negative mode. This aims for not only the simultaneous detection of veterinary drugs regulated in Brazil but also the prospection of antimicrobials not yet monitored. Two different sample preparation procedures were applied: method A-generic solid-liquid extraction with 0.1% formic acid (v/v) in an aqueous solution of EDTA 0.1% (w/v)-acetonitrile-methanol (1:1:1, v/v/v), followed by an additional ultrasound-assisted extraction and method B-QuEChERS. In both procedures, selectivity showed satisfactory conformity. From a detection capability (CCß) equivalent to ½ the maximum residue limit, >34% of the analyte resulted in a false positive rate of <5%, preponderant by the QuEChERS method, which exhibited a higher yield of the sample. The results showed the potential application of both procedures in the routine analysis of foods by official laboratories, enabling the expansion of this methodological portfolio as well as its analytical scopes, thus optimizing the control of residues of veterinary drugs in the country.

Analytical Methods for the Quality Control of Veterinary Antimicrobials Medicines.

Veterinary medicinal products (VMPs) are used for the prevention and treatment of diseases in animals. The safety and efficacy of these products must be proven by quality control tests. Special attention should be paid to veterinary antimicrobials medicines (VAMs), as changes in their potency can compromise pharmacotherapeutic treatment and contribute to microbial resistance. The aim of this work was to review the analytical methods available for assessing the quality of VAMs, to analyze regulatory issues and quality control programs. The review was performed on selected papers in the PubMed, ScienceDirect, Scopus and Virtual Health Library databases, between 2005 and 2020. After applying exclusion criteria, 19 studies were obtained. Of the analytical studies, the majority (61.54%) used the HPLC technique. In addition, methods by CE (15.39%) and by SPM, FIA and microbiological assay (7.69% each) were found. In studies of monitoring of VAMs available on the market, changes in tylosin, spiramycin, ampicillin, tetracyclines and penicillins were observed. This is worrying, as these quality deviations can contribute to the development of resistant microorganisms. Although international efforts have been implemented at the regulatory level to ensure the quality of VAMs, it was realized with this study that there is much to evolve in the development of new analytical methods and in monitoring the quality of VAMs. With this, it is expected that this study will instigate scientists in the analytical, regulatory, microbiological and veterinary fields to develop new research so that the demands necessary to guarantee the quality of VAMs are increasingly met.

Environmentally realistic concentrations of eprinomectin induce phytotoxic and genotoxic effects in Allium cepa.

Eprinomectin, a veterinary drug within the family of avermectins, is widely used in the agricultural sector to combat a variety of parasites, mainly nematodes. However, only 10% of the drug is metabolized in the organism, so large quantities of the drug are released into the environment through urine and/or feces. Soil is the first and main environmental compartment to be contaminated by it, and nontargeted organisms can be affected. Thus, the present study aims to evaluate the phytotoxicity (through the evaluation of germination, root development, and germination speed) and genotoxicity (through an assessment of the induction of micronuclei and chromosomal aberrations) of eprinomectin. For the analyses, Allium cepa seeds were germinated in soil contaminated with a range of concentrations of eprinomectin: from 0.5 to 62.5 µg/g for the genotoxicity test and from 0.5 to 128.0 µg/g for the phytotoxicity test. The results showed that seed germination was not affected, but root development was affected at concentrations of 0.5 µg/g, 1.0 µg/g, 4.0 µg/g, 8.0 µg/g, 64.0 µg/g, and 128.0 µg/g, and germination speed was significantly changed at concentrations of 1.0 µg/g, 4.0 µg/g, 16.0 µg/g, 32.0 µg/g, and 64.0 µg/g. Significant differences in the mitotic index and genotoxicity index were observed only at concentrations of 2.5 µg/g and 12.5 µg/g, respectively. Only the 0.5 µg/g concentration did not show significant induction of micronuclei in the meristematic cells, but the damage observed at other concentrations did not persist in F1 cells. According to the results, eprinomectin is both phytotoxic and genotoxic, so the release of eprinomectin into the environment should be minimized.

Residues of Veterinary Drugs in Animal Products Commercialized in the Border Region of Brazil, Argentina, and Uruguay.

ABSTRACT: The traffic in international animal products can become a public health hazard when legal import sanitary procedures are not followed. In Brazil, due to its extensive border area, the importation of animal products is a common practice in many areas, especially in Rio Grande do Sul, a state that borders Argentina and Uruguay. The objective of this study was to evaluate the presence of veterinary drug residues (antibiotics and antiparasitics) in animal products consumed in Rio Grande do Sul. The presence of residues of veterinary antibiotics and antiparasitics was assessed in 189 meat (beef, pork, and chicken), processed dairy, and meat product samples bought in Argentina (n = 90) and Uruguay (n = 99). Residues of these veterinary drugs were detected in 50 (26.45%) of the samples; 28 samples (14.81%) had antibiotic residues, and 22 samples (11.64%) had antiparasitic residues. Of the 50 positive samples, 40% (15 from Argentina and 5 from Uruguay) had residues above the maximum residue limits (MRLs). Of these 20 samples, 12 had antiparasitic residues above the MRLs (11 beef samples had ivermectin and 1 pork sample had ivermectin and doramectin) and 8 had antibiotic residues above the MRLs (2 pork and 2 sausage samples had doxycycline, 2 cheese samples had doxycycline and chlortetracycline, 1 poultry meat sample had chloramphenicol, and 1 cheese sample had monensin). Because of the potential toxic effects on humans and the potential for pathogens to develop antibiotic resistance, the presence of these residues above the MRLs is a potential risk to public health. The negative impact of consumption of imported animal products can be reduced by implementation of an effective surveillance system and educational campaigns for the general population.

Validation of the QuEChERSER mega-method for the analysis of pesticides, veterinary drugs, and environmental contaminants in tilapia (Oreochromis Niloticus).

Diverse food safety programmes around the world are designed to help ensure production of safe food. To meet this need, the development and implementation of more efficient and effective analytical methods to monitor residues (pesticides and veterinary drugs) and contaminants in food is important. In this study, we report the validation results for a simple high-throughput mega-method for residual analysis of 213 pesticides and veterinary drugs, including 15 metabolites, plus 12 environmental contaminants (polychlorinated biphenyls) in tilapia muscle for implementation in routine laboratory analyses. The generic sample preparation method and analytical approach are known as QuEChERSER (more than QuEChERS). A small portion of the initial extract (204 µL) is taken for analysis by ultrahigh-performance liquid chromatography (UHPLC) tandem mass spectrometry (MS/MS) covering 145 analytes, and the remaining extract undergoes a salting out step followed by an automated robotic instrument top sample preparation (ITSP) cleanup, also known as micro-solid-phase extraction (µSPE), plus fast low-pressure gas chromatography LPGC-MS/MS for 134 analytes (66 pesticides are targeted in both UHPLC-MS/MS and LPGC-MS/MS). The mega-method was validated in spiked tilapia samples at 5, 10, 15, and 20 ng/g with 10 replicates per level over two days (n = 80 overall), and 70-140% recoveries with RSDs ≤20% were achieved for 92% of the analytes in LC and 82% in GC. No significant matrix effects were observed for the analytes in LPGC-MS/MS, and only 5% of the analytes exceeded ±20% matrix effect in UHPLC-MS/MS. Analysis of standard reference materials (NIST SRMs 1946 and 1947) for contaminants in freeze-dried fish showed acceptable results, further demonstrating that the QuEChERSER mega-method can be implemented to expand analytical scope and increase laboratory efficiency compared to the QuEChERS method.

Desenvolvimento de organogel injetável subcutâneo de Pluronic®-F127 e lecitina de soja (OPL) contendo meloxicam para uso veterinário / Development of a veterinary organogel formulation containing soy lecithin, Pluronic® F-127 and meloxicam for the treatment of acute and chronic pain in small animals

O organogel é formado por uma matriz tridimensional composta de filamentos que se auto-organizam em uma rede entrelaçada e que, por seu tipo de estrutura, pode ser utilizado com o objetivo de atuar como um implante que se forma in situ, sendo capaz de se comportar como uma forma farmacêutica de liberação prolongada. Esse trabalho tem, por tanto, o objetivo desse trabalho foi desenvolver, caracterizar, quantificar e traçar perfis de dissolução para formulações de organogel contendo meloxicam como principio ativo. O material está dividido em quatro capítulos, sendo apresentada inicialmente (I) revisão da literatura a respeito da lecitina de origem vegetal, com suas principais fontes de obtenção, como soja, girassol e colza, e também seu uso farmacêutico na obtenção de formulações como organogéis, microemulsões e lipossomas. Os demais capítulos abordam (II) desenvolvimento e otimização de uma formulação de organogel contendo lecitina de soja e Pluronic® F-127 como formadores da matriz tridimensional e meloxicam como principio ativo. (III) Desenvolvimento e validação de um método de quantificação do teor de meloxicam por cromatografia líquida de alta eficiência (CLAE). (IV) Desenvolvimento de um método de dissolução para formulações de organogel, que fosse capaz de ser utilizado na caracterização do perfil de dissolução de diferentes formulações. Com os resultados obtidos, foi possível desenvolver formulações de organogel contendo lecitina de soja, Pluronic® F-127 e meloxicam, assim como um método analítico validado para as analises de teor. Por fim, foram obtidos também os perfis de dissolução de duas formulações mais promissoras

Organogels are formed by a three-dimensional matrix composed of filaments that selforganize in an interlaced network and that, due to its type of structure, can be used with the objective of acting as an implant that forms in situ, being able to behave as an extendedrelease dosage form. This work has, therefore, the objective of this work was to develop, characterize, quantify and trace dissolution profiles for organogel formulations containing meloxicam as active ingredient. The material is divided into four chapters, initially presented (I) review of the literature on lecithin of plant origin, with its main sources of production, such as soybean, sunflower and rapeseed, and also its pharmaceutical use in obtaining formulations such as organogels , microemulsions and liposomes. The remaining chapters address (II) development and optimization of an organogel formulation containing soy lecithin and Pluronic® F-127 as three-dimensional matrix formers and meloxicam as an active ingredient. (III) Development and validation of a method for quantification of meloxicam content by high performance liquid chromatography (HPLC). (IV) Development of a dissolution method for organogel formulations, capable of being used to characterize the dissolution profile of different formulations. With the results obtained, it was possible to develop organogel formulations containing soy lecithin, Pluronic® F-127 and meloxicam, as well as a validated analytical method for content analysis. Finally, the dissolution profiles of two more promising formulations were also obtained

Temporal and spatial patterns in the detection of veterinary drug residues in poultry and swine in Brazil / Padrões temporais e espaciais na detecção de resíduos de medicamentos veterinários em aves e suínos no Brasil

Food Safety is an important topic for public health and international trade in food. Residues of veterinary drugs and environmental contaminants in animal products can cause diseases and acute toxicity in organisms exposed to these substances. This study evaluated official monitoring data of veterinary drug residues from the Brazilian Ministry of Agriculture, Livestock and Supply in tissues of poultry and swine in the period between 2002 and 2014 to check for hidden patterns in the occurrence of six common drugs (Closantel, Diclazuril, Nicarbazin, Sulfaquinoxaline, Doxycycline and Sulfamethazinein). The analysis of data was performed by using two machine learning methods: decision tree and neural networks, in addition to visual evaluation through graphs and maps. Contamination rates were low, varying from 0 to 0.66%. A spatial distribution pattern of detections of substances by region was identified, but no pattern of temporal distribution was observed. Nevertless, regressions showed an increase in levels when these substances were detected, so monitoring should continue. However, the results show that the products monitored during the study period presented a low risk to public health.(AU)

A Segurança Alimentar é um tema importante para a saúde pública e o comércio internacional de alimentos. Resíduos de medicamentos veterinários e contaminantes ambientais em produtos de origem animal podem causar doenças e toxicidade aguda em organismos expostos a essas substâncias. Este estudo avaliou dados oficiais de monitoramento de resíduos de medicamentos veterinários do Ministério da Agricultura, Pecuária e Abastecimento em tecidos de aves e suínos no período de 2002 a 2014 para verificar padrões ocultos na ocorrência de seis medicamentos comuns (Closantel, Diclazuril, Nicarbazina, Sulfaquinoxalina, Doxiciclina e Sulfametazina). A análise dos dados foi realizada por meio de dois métodos de aprendizado de máquina: árvore de decisão e redes neurais, além da avaliação visual por meio de gráficos e mapas. As taxas de contaminação foram baixas, variando de 0 a 0,66%. Foi identificado um padrão de distribuição espacial das detecções de substâncias por região, mas nenhum padrão de distribuição temporal foi observado. No entanto, as regressões mostraram um aumento nos níveis quando essas substâncias foram detectadas, portanto, o monitoramento deve continuar. No entanto, os resultados mostram que os produtos monitorados durante o período do estudo apresentaram baixo risco à saúde pública.(AU)

Ethnoveterinary for food-producing animals and related food safety issues: A comprehensive overview about terpenes.

Alternatives to the use of conventional veterinary drugs in food-producing animals have gained attention, such as the use of natural products (NPs), mainly to soften the risks to the animal, the environment, and consumer's health. Although NPs have consistent advantages over conventional drugs, they cannot be considered risk free under food safety matters. In this way, this document presents a comprehensive overview of the importance of considering both the pharmacological and toxicological properties of the constituents of a NP from plants intending the standardization and regulation of its use in food-producing animals. Terpenes are the most diverse class of natural substances present in NP of vegetal origin with a broad range of biological activities that can be explored in veterinary science; however, certain plants and terpenes also have significant toxic effects, a fact that can harm the health of animals and consequently generate economic losses and risks for humans. In this context, this review gathered scientific data of vegetal species of importance to ethnoveterinary for food-producing animals, which produce terpenes, its biological effects, and their implications on food safety issues for consumers. For this, more than 300 documents were selected from different online scientific databases. The present data and discussion may contribute to the rational commercial exploration of this class of NPs in veterinary medicine.

Monensin occurrence in surface water and its impact on aquatic biota in a stream of the southeast Pampas, Argentina.

Monensin is an ionophore antibiotic used as a feed additive and growth promoter in cattle production worldwide. The occurrence of monensin in aquatic surficial ecosystems is of concern due to its possible detrimental effects on human health and native biota. Argentina is one of the most important cattle beef producers worldwide; however, there is little knowledge on the environmental occurrence of monensin and the associated risks to aquatic biota. In this study, we developed a method for the extraction and quantification of monensin in surface water; then, we evaluated the occurrence of monensin in a stream impacted by different animal husbandry's operations, and then, we analyzed the ecological implications of monensin residues on aquatic organisms using the risk quotient (RQ) method. Sampling was carried out on August 2017 from the headwaters to the floodplain of the El Pantanoso stream, Buenos Aires province, Argentina. Monensin detection frequency was 75% (n = 20). The median level was 0.40 µg/L and the maximum concentration was 4.70 µg/L. The main input of monensin was from a cattle slaughterhouse, an activity that has not been considered before in the literature as a source of emission of veterinary pharmaceuticals into the environment. The RQ assessment showed that monensin levels could have potential negative effects on aquatic biota in the sampling site closest to the cattle slaughterhouse. The data obtained in this study shows that monensin was present in El Pantanoso surface waters at levels of high ecotoxicological risk to aquatic biota.

High-Throughput Mega-Method for the Analysis of Pesticides, Veterinary Drugs, and Environmental Contaminants by Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry and Robotic Mini-Solid-Phase Extraction Cleanup + Low-Pressure Gas Chromatography-Tandem Mass Spectrometry, Part 1: Beef.

In this work, a new mega-method of sample preparation called "QuEChERSER" (more than QuEChERS) is being presented for the first time. Fast, efficient, and cost-effective analysis of chemical contaminants in meat is useful for international trade, domestic monitoring, risk assessment, and other purposes. The goal of this study was to develop and validate a simple high-throughput mega-method for residual analysis of 161 pesticides, 63 veterinary drugs, 24 metabolites, and 14 legacy environmental contaminants (polychlorinated biphenyls) in bovine muscle for implementation in routine laboratory analyses. Sample preparation of 2 g test portions entailed QuEChERS-based extraction with 10 mL of 4:1 (v/v) acetonitrile/water, and then 204 µL was taken, diluted, and ultracentrifuged prior to analysis of veterinary drugs and pesticides by ultra-high-performance liquid chromatography-tandem mass spectrometry. The remaining extract was salted out with 4:1 (w/w) anhydrous MgSO4/NaCl, and 1 mL was transferred to an autosampler vial for automated mini-cartridge solid-phase extraction (Instrument Top Sample Preparation) cleanup with immediate injection using fast low-pressure gas chromatography-tandem mass spectrometry analysis. The automated cleanup and both instruments were all operated in parallel in 13-15 min cycle times per sample. Method validation according to United States Department of Agriculture requirements demonstrated that 221 (85%) of the 259 analytes gave average recovery between 70 and 120% and interday relative standard deviation of ≤25%. Analysis of a certified reference material for veterinary drugs in freeze-dried bovine muscle was also very accurate, further demonstrating that the QuEChERSER mega-method can be implemented to save time, labor, and resources compared to current practices to use multiple methods to cover the same analytical scope.

New Trends in Drug Delivery Systems for Veterinary Applications.

BACKGROUND: The veterinary pharmaceutical industry has shown significant growth in recent decades. Several factors contribute to this increase as the demand for the improvement of the quality of life of both domestic and wild animals, together with the need to improve the quality, productivity, and safety of foodstuffs of animal origin. METHODS: The goal of this work was to identify the most suitable medicines for animals that focus on drug delivery routes as those for humans, although they may have different devices, such as collars and ear tags. RESULTS: Recent advances in drug delivery systems for veterinary use are discussed, both from academic research and the global market. The administration routes commonly used for veterinary medicines are also explored, while special attention is given to the latest technological trends to improve the drug performance, reducing the number of doses, animal stress, and side effects. CONCLUSION: Drug delivery system in veterinary decreased the number of doses, side effects, and animal stress that are a small fraction of the benefits of veterinary drug delivery systems and represent a significant increase in profit for the industry; also, it demands investments in research regarding the quality, safety, and efficacy of the drug and the drug delivery systems.

Perspectives of photodynamic therapy in biotechnology.

Photodynamic therapy (PDT) is a current and innovative technique that can be applied in different areas, such as medical, biotechnological, veterinary, among others, both for the treatment of different pathologies, as well as for diagnosis. It is based on the action of light to activate photosensitizers that will perform their activity on target tissues, presenting high sensitivity and less adverse effects. Therefore, knowing that biotechnology aims to use processes to develop products aimed at improving the quality of life of human and the environment, and optimizing therapeutic actions, researchers have been used PDT as a tool of choice. This review aims to identify the impacts and perspectives and challenges of PDT in different areas of biotechnology, such as health and agriculture and oncology. Our search demonstrated that PDT has an important impact around oncology, minimizing the adverse effects and resistance to chemotherapeutic to the current treatments available for cancer. Veterinary medicine is another area with continuous interest in this therapy, since studies have shown promising results for the treatment of different animal pathologies such as Bovine mastitis, Malassezia, cutaneous hemangiosarcoma, among others. In agriculture, PDT has been used, for example, to remove traces of antibiotics of milk. The challenges, in general, of PDT in the field of biotechnology are mainly the development of effective and non-toxic or less toxic photosensitizers for humans, animals and plants. We believe that there is a current and future potential for PDT in different fields of biotechnology due to the existing demand.

Tetracyclines lead to ammonium accumulation during nitrification process.

The effect of tetracyclines used for swine food-production (tetracycline and oxytetracycline) on enriched nitrifying bacteria cultures over time was investigated in this study. Short-term exposure assays were performed in different concentrations of each antibiotic, using ammonia oxidizing bacteria (AOB) culture and nitrifying bacteria. The results pointed out a higher inhibitory effect of tetracycline on both bacterial communities. The AOB was more sensitive to antibiotic exposure when compared to the nitrifying culture. Although high antibiotic concentrations were applied, the half maximal inhibitory concentration (IC50) was achieved only for the AOB culture exposed to tetracycline at a concentration of 273 mg L-1. Nonetheless, the long-term exposure assay demonstrated a reduction of the tetracycline inhibition effect against AOB. The exposure to 100 mg L-1 of tetracycline (TC) did not show relevant influence over ammonium conversion efficiency; however, at 128 mg L-1 of TC, the efficiency decreased from 94% to 72%. Further investigation revealed that TC reduced the final effluent quality due to the development of a resistance mechanism by AOB culture against this antibiotic. This mechanism involves increasing the excretion of extracellular polymeric substances (EPS) and soluble microbial products (SMP), which probably increases BOD, and reduces ammonia consumption by the bacterial culture.

Determination of steroids in bovine hair: Validation of a microwave-assisted chemical derivatization method using liquid chromatography-tandem mass spectrometry and in vivo studies.

Hair analysis has attracted great attention in the regulatory analysis of food-producing animals, particularly due to the wider detection window of veterinary drugs in this matrix and also the possibility of confirming parent drugs with minimum metabolization. This work involved the development and validation of a quantitative liquid chromatography-tandem mass spectrometry method to determine 25 steroids and steroid esters in bovine hair. Sensitivity was improved using a fast and effective microwave-assisted chemical derivatization with methoxyamine hydrochloride. The validation was conducted in accordance with the Decision 657/2002/EC guidelines. An animal experimentation procedure was performed on 12 bovine animals in which two commercial formulations containing boldenone undecylenate and testosterone propionate were administrated via intramuscular injections on the neck. The samples were collected for 78 days in which the detection of the administrated analytes was only observed near the application sites. For some of the monitored days, no analyte was detected on the neck area. Since the migration of the analytes was not observed in areas other than the application site, false-negative results should be carefully considered when monitoring animal hair samples.