Quantification of Veterinary Antibiotics in Pig and Poultry Feces and Liquid Manure as a Non-Invasive Method to Monitor Antibiotic Usage in Livestock by Liquid Chromatography Mass-Spectrometry

Antibiotics are active substances frequently used to treat and prevent diseases in animal husbandry, especially in swine and poultry farms. The use of manure as a fertilizer may lead to the dispersion of antibiotic residue into the environment and consequently the development of antibiotic-resistant bacteria. Most pharmaceutical active ingredients are excreted after administration, in some cases up to 90% of the consumed dose can be found in the feces and/or urine as parent compound. Therefore, due to antibiotic metabolism their residues can be easily detected in manure. This article describes a method for simultaneous analysis of ciprofloxacin, chlortetracycline, doxycycline, enrofloxacin, lincomycin, oxytetracycline, tetracycline, tiamulin, trimethoprim and tylosin in feces, liquid manure and digestate. Antibiotics were extracted from the different matrices with McIlvaine-Na2EDTA buffer solution and the extract was purified by the use two techniques: d-SPE and SPE (Strata-X-CW cartridges) and final eluent was analyzed by LC-MS and LC-MS/MS. The European Commission Decision 2002/657/EC was followed to conduct the validation of the method. Recoveries obtained from spiked pig and poultry feces and liquid manures samples ranged from 63% to 93% depending on analytes. The analysis of 70 samples (feces, liquid manure and digestate) revealed that 18 samples were positive for the presence of doxycycline, oxytetracycline, tetracycline, chlortetracycline, enrofloxacin, tiamulin and lincomycin. The results obtained in the presented study demonstrated that animal feces can be used as a non-invasive method detection antibiotic usage in animal productionThe study was financially supported by the KNOW (Leading National Research Centre) Scientific Consortium “Healthy Animal—Safe Food”, decision of Ministry of Science and Higher Education No. 05-1/KNOW2/2015S

Detached cataclysmic variables are crossing the orbital period gap

A central hypothesis in the theory of cataclysmic variable (CV) evolution is the need to explain the observed lack of accreting systems in the ~2-3 h orbital period range, known as the period gap. The standard model, disrupted magnetic braking (DMB), reproduces the gap by postulating that CVs transform into inconspicuous detached white dwarf (WD) plus main sequence (MS) systems, which no longer resemble CVs. However, observational evidence for this standard model is currently indirect and thus this scenario has attracted some criticism throughout the last decades. Here we perform a simple but exceptionally strong test of the existence of detached CVs (dCVs). If the theory is correct dCVs should produce a peak in the orbital period distribution of detached close binaries consisting of a WD and an M4-M6 secondary star. We measured six new periods which brings the sample of such binaries with known periods below 10 h to 52 systems. An increase of systems in the ~2-3 h orbital period range is observed. Comparing this result with binary population models we find that the observed peak can not be reproduced by PCEBs alone and that the existence of dCVs is needed to reproduce the observations. Also, the WD mass distribution in the gap shows evidence of two populations in this period range, i.e. PCEBs and more massive dCVs, which is not observed at longer periods. We therefore conclude that CVs are indeed crossing the gap as detached systems, which provides strong support for the DMB theory.Comment: 12 pages, 6 figures, 2 tables, accepted for publication in MNRA

Swine Production: Probiotics as an Alternative to the Use of Antibiotics

Animal food production is one of the most powerful European economic sectors; however, this sector is facing new challenge due to the development of bacteria with resistant genes, and consequently, restriction on the administration of antibiotics. Limitation, at the moment, is focused on those antibiotics employed in human medicines. Therefore, it is necessary to improve as much as possible animals’ health and reduce diseases. Among others, alternatives include adequate animal handling, hygienic facilities, quality food, or vaccines. Probiotics also arise as a good alternative due to their already known properties as intestinal microbiota modulators, improving the immune functions and reducing the risk and the development of illness. Significant data can found scientific literature that demonstrates probiotics benefits when they are administrated to the animals through diet. However, to be able to apply all these findings in a specific animal species, at a particular production animal life stage and at a industrialize scale, it is necessary to compile and organize reported information. This chapter presents the most recent and relevant finding on the use of probiotics in swine production

Monitoring the presence of 13 active compounds in surface water collected from rural areas in northwestern Spain

Drug residues are considered environmental contaminants, and their occurrence has recently become a matter of concern. Analytical methods and monitoring systems are therefore required to control the continuous input of these drug residues into the environment. This article presents a suitable HPLC-ESI-MS/MS method for the simultaneous extraction, detection and quantification of residues of 13 drugs (antimicrobials, glucocorticosteroids, anti-inflammatories, anti-hypertensives, anti-cancer drugs and triphenylmethane dyes) in surface water. A monitoring study with 549 water samples was carried out in northwestern Spain to detect the presence of drug residues over two sampling periods during 2010, 2011 and 2012. Samples were collected from rural areas with and without farming activity and from urban areas. The 13 analytes were detected, and 18% of the samples collected showed positive results for the presence of at least one analyte. More collection sites were located in rural areas than in urban areas. However, more positive samples with higher concentrations and a larger number of analytes were detected in samples collected from sites located after the discharge of a WWTP. Results indicated that the WWTPs seems to act as a concentration point. Positive samples were also detected at a site located near a drinking water treatment plantThe authors wish to thank the Fondo Europeo Agrícola de Desarrollo Rural (FEADER) and the Consellería de Medio Rural for funding this study through the project FMR331A, and the staff of the Cactus of the University of Santiago de Compostela for their help in the analysis of the samplesS

Determination of the Presence of Three Antimicrobials in Surface Water Collected from Urban and Rural Areas

Due to the continuous release of antimicrobials into the environment, the aim of this study was to compare the frequency of detection of sulfamethazine, sulfamethoxypyridazine and trimethoprim in surface water collected from urban and rural areas in Northwestern Spain. A monitoring study was conducted with 314 river water samples analyzed by high-performance liquid chromatography coupled to tandem mass spectrometry. The results indicated that 37% of the samples contained residues of at least one of the investigated antimicrobials, and every sampling site yielded positive samples. At sites located near the discharge points of wastewater treatment plants and near the collection point of a drinking-water treatment plant, more than 6% of the samples were positive for the presence of antimicrobial residuesThe authors wish to thank the Fondo Europeo Agrícola de Desarrollo Rural (FEADER) and the Consellería de Medio Rural for funding this study through the Project FMR331AS

Eliciting tomato plant defenses by exposure to herbivore induced plant volatiles

[EN] When zoophytophagous mirids (Hemiptera: Miridae) feed on tomato plants they activate both direct and indirect defense mechanisms, which include the release of herbivore induced plant volatiles (HIPVs). HIPVs are capable of activating defense mechanisms in healthy neighboring plants. In this work, we investigated which of these mirid-induced HIPVs are responsible for inducing plant defenses. Healthy tomato plants were individually exposed to eight HIPVs [1-hexanol, (Z)-3-hexenol, (Z)-3-hexenyl acetate, (Z)-3-hexenyl propanoate, (Z)-3-hexenyl butanoate, hexyl butanoate, methyl jasmonate and methyl salicylate] for 24 hours. Then, the expression level of defensive genes was quantified. All HIPVs led to increased expression of defensive genes by the plant when compared to unexposed tomato plants. In a further step, (Z)-3-hexenyl propanoate and methyl salicylate were selected to study the response of four tomato key pests and one natural enemy to tomato plants previously exposed to both HIPVs relative to unexposed control plants. Plants previously exposed to both HIPVs were repellent to Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) and Frankliniella occidentalis Pergande (Thysanoptera: Thripidae), attractive to the parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae) and indifferent to Tetranychus urticae Koch (Acari: Tetranychidae). The volatiles emitted by plants previously exposed to both selected volatiles were also determined. Increased levels of C5 and C6 fatty acid-derived volatile compounds and beta-ionone were detected, confirming that both HIPVs significantly activated the lipoxygenase pathway. These results are the starting point to advance the use of volatile compounds as defense elicitors in tomato crops.The research leading to these results was partially funded by the Spanish Ministry of Economy and Competitiveness MINECO (AGL2014-55616-C3 and RTA201700073-00-00) and the Conselleria d'Agricultura, Pesca i Alimentacio de la Generalitat Valenciana. The authors thank Dr. Alejandro Tena (IVIA) and Alice Mockford (University of Worcester) for helpful comments on earlier versions of the manuscript.Perez-Hedo, M.; Alonso-Valiente, M.; Vacas, S.; Gallego, C.; Rambla Nebot, JL.; Navarro-Llopis, V.; Granell Richart, A.... (2021). Eliciting tomato plant defenses by exposure to herbivore induced plant volatiles. Entomologia Generalis. 41(3):209-218. https://doi.org/10.1127/entomologia/2021/1196S20921841

Efficacy of different waste and by-products from forest and food industries in the removal/retention of the antibiotic cefuroxime

Environmental pollution due to antibiotics is a serious problem. In this work, the adsorption and desorption of the antibiotic cefuroxime (CFX) were studied in four by-products/residues from the forestry and food industries. For this, batch-type experiments were carried out, adding increasing concentrations of CFX (from 0 to 50 µmol L−1) to 0.5 g of adsorbent. The materials with a pH higher than 9 (mussel shell and wood ash) were those that presented the highest adsorption percentages, from 71.2% (23.1 µmol kg−1) to 98.6% (928.0 µmol kg−1). For the rest of the adsorbents, the adsorption was also around 100% when the lowest concentrations of CFX were added, but the percentage dropped sharply when the highest dose of the antibiotic was incorporated. Adsorption data fitted well to the Langmuir and Freundlich models, with R2 greater than 0.9. Regarding desorption, the materials that presented the lowest values when the highest concentration of CFX was added were wood ash (0%) and mussel shell (2.1%), while pine bark and eucalyptus leaves presented the highest desorption (26.6% and 28.6%, respectively). Therefore, wood ash and mussel shell could be considered adsorbents with a high potential to be used in problems of environmental contamination by CFX.Agencia Estatal de Investigación | Ref. RTI2018-099574-B-C21Agencia Estatal de Investigación | Ref. RTI2018-099574-B-C2

Presencia y resistencia a antimicrobianos de Escherichia coli aislados a partir de alimentos en el estado de Hidalgo (México)

The presence of Escherichia coli in foods taken from the grocery stores and the supermarkets in Hidalgo State (Mexico) was determined for 73 samples of poultry meat, 60 samples of pork, 86 samples of beef, and 66 samples of vegetables. A total of 352 E. coli strains were isolated, identified, and analyzed by an agar disk diffusion assay for their resistance to 10 antimicrobials. Poultry meat and vegetables taken from groceries showed significantly higher counts (P = 0.0002 and P = 0.0461, respectively) when compared with the samples taken from supermarkets. Compared with the isolates recovered from other foods, E. coli isolated from chicken meat had higher levels of antimicrobial resistance against all antimicrobials tested, with the exceptions of nitrofurantoin resistance of isolates from pork and streptomycin resistance in isolates from pork and beef. In addition, the E. coli isolates from samples taken from the groceries showed higher resistance rates than the isolates from samples taken from the supermarkets for the cases of pork isolates resistance to ampicillin (P = 0.0497), chloramphenicol (P = 0.0075), doxycycline (P = 0.002), and streptomycin (P = 0.0094) and beef isolates resistance against ampicillin (P = 0.0048), streptomycin (P = 0.002), and sulfisoxazole (P = 0.003). The present study revealed that the observed resistance rates correlated well with those reported in the national surveillance programmes of developed countries, with the exception of isolates from chicken meat, which have higher resistance rates. Also, from a microbiological safety point of view, samples taken from supermarkets were in a much better conditions than those obtained from the groceriesLa presencia de Escherichia coli fue investigada en 73 muestras de carne de pollo, 60 muestras de carne de cerdo, 86 muestras de carne de vacuno y 66 muestras de alimentos vegetales muestreados en pequeños ultramarinos y supermercados en el estado de Hidalgo (México). Un total de 352 aislamientos de E. coli fueron seleccionados, identificados y analizados mediante el método de difusión en disco para determinar su resistencia a 10 antimicrobianos. Las muestras de pollo y vegetales obtenidas en tiendas de alimentación mostraron recuentos de E. coli significativamente mayores (P = 0,0002 y P = 0,0461 respectivamente) que las obtenidas en supermercados. Comparados con los procedentes de los restantes alimentos, los E. coli obtenidos a partir de carne de pollo mostraron un mayor grado de resistencia a todos los antimicrobianos estudiados, excepto en lo referente a la nitrofurantoína en el caso de los aislados a partir de carne de cerdo y la estreptomicina respecto de los aislamientos de carne de cerdo y vacuno. Adicionalmente, en algunos casos, los E. coli obtenidos a partir de alimentos muestreados en pequeños ultramarinos mostraron mayores tasas de resistencia que los procedentes de alimentos muestreados en supermercados. Esto ocurrió en los aislamientos procedentes de carne de cerdo para la ampicilina (P = 0,0497), cloranfenicol (P = 0,0075), doxiciclina (P = 0,002) y estreptomicina (P = 0,0094), y en el caso de la carne de vacuno para la ampicilina (P = 0,0048), estreptomicina (P = 0,002) y sulfizoxazol (P = 0,003). El presente estudio demuestra que las tasas de resistencia observadas son compatibles con las publicadas en los programas nacionales de vigilancia de los países desarrollados, con la excepción de los aislamientos procedentes de carne de pollo, en los cuales las tasas de resistencia tienden a ser mayores. Además, desde el punto de vista de la seguridad microbiológica, las muestras obtenidas en supermercados mostraron condiciones significativamente mejores que las obtenidas en tiendas de alimentaciónThe authors are thankful for financial support from Dirección Xeral de Investigación, Desenvolvemento e Innovación (Xunta de Galicia) (grant IN843A2007/42), and CONACYT (Project CB-2006–61310)S