Master of Science / Department of Grain Science and Industry / Leland McKinney / Carryover of medicated feed additives between batches of feed can potentially result in harmful drug residues in the edible tissues of food-animals. Flushing the equipment with an ingredient, such as ground grain, is one method used to remove any residual medicated feed from the system. It is generally recommended that the quantity of flush used be between 5 and 10% of the mixer's capacity. However, there is little data that supports this recommendation. Therefore, two experiments were conducted to 1.)determine which manufacturing equipment is the major source of carryover, 2.)evaluate which flush size adequately prevents drug carryover, and 3.) quantify the interrelationship between flush size and drug concentration. In Experiment 1, feed medicated with nicarbazin (Nicarb 25%®; 0.0125%) was manufactured and conveyed from the mixer, through a drag conveyor and bucket elevator, and then into a finished product bin. The system was then flushed using ground corn in the amount of 2.5, 5, 10, 15, or 20% of the mixer's capacity (454.5 kg). Subsequently, a non-medicated diet was conveyed through the system and samples were collected and analyzed for nicarbazin. No significant (P > 0.05) differences were detected among the flush treatments, and all treatments were effective in preventing nicarbazin carryover to the non-medicated diet. In Experiment 2, feed medicated with three levels of monensin (Rumensin® 80; 100, 600, and 1,200 g/ton) was manufactured and handled in the same manner as in Experiment 1. The flushing treatments examined were: 1, 2.5, and 5% of the mixer's capacity. Samples of the non-medicated diet for each treatment were collected and analyzed for monensin. There was significant interaction (P < 0.05)between drug level and sampling location between treatments. As the drug level in the medicated diet increased, higher concentrations of monensin were detected in the non-medicated diet. Collectively, these studies demonstrate that a 2.5%, even a 1% flush size, is effective in preventing carryover of medicated feed additives. It was also demonstrated that the bucket elevator and finished product bin were the major sources of drug carryover in this particular feed manufacturing system.

Orientador: Felix Guillermo Reyes Reyes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-21T10:37:11Z (GMT). No. of bitstreams: 1 Rezende_RenataAntunesEstaianode_M.pdf: 1522270 bytes, checksum: a0ea23b47147c504a5e5f70c7a0d1fbd (MD5) Previous issue date: 2012 / Resumo: A piscicultura no Brasil tem crescido de maneira significativa ao longo dos últimos 20 anos, refletido pelo aumento da produção com elevadas densidades de estocagem. Com a intensificação da atividade aquícola, o surgimento de surtos causados por vários agentes etiológicos tornam-se cada vez mais freqüentes, dentre eles as bacterioses. Para combater o agente responsável por essas enfermidades, muitos antibióticos são utilizados de maneira ilícita, podendo, além de não apresentar efetividade durante o tratamento, causar letalidade aos animais e danos ambientais. Atualmente, o Brasil possui apenas dois antimicrobianos aprovados para uso na aquicultura: florfenicol e oxitetraciclina. A enrofloxacina (ENR) é um antibiótico largamente utilizado na medicina veterinária por apresentar elevado potencial de eficácia no tratamento de bacterioses. Porém, apesar de no Brasil ainda não ter uso regulamentado na piscicultura, muitos produtores acabam utilizando-a de forma ilícita, sendo adicionada à ração ou em banhos de imersão. Esses procedimentos de administração favorecem a perda do fármaco por meio da lixiviação, promovem a mudança do ecossistema aquático, além de prejudicar a saúde animal e do consumidor. Possíveis alternativas para facilitar a administração da ENR, minimizando os problemas causados no meio ambiente, são os revestimentos na ração, um dos mais antigos processos farmacêuticos ainda existentes e com grande aplicabilidade em diversos segmentos. Para a formação desses revestimentos, os polímeros utilizados precisam ser compatíveis com as características químicas e físico-químicas do fármaco, garantindo homogeneidade ao produto final e redução de perda do medicamento ao longo do tempo de administração da ração. Para tanto, faz-se necessário o revestimento da ração medicada seguida da avaliação das taxas de lixiviação, a fim de avaliar as perdas do fármaco para o ambiente. Para alcançar este objetivo, é necessária a disponibilidade de um método analítico devidamente validado que garanta a determinação do teor, antes e depois do processo de lixiviação da ração medicada. O método desenvolvido para quantificação da ENR na ração foi baseado na técnica de cromatografia líquida de alta eficiência com detector de arranjo de diodos (HPLC-DAD). O método foi validado considerando os seguintes parâmetros: linearidade, sensibilidade, seletividade, precisão intradia e interdias, exatidão, limite de detecção, limite de quantificação. Os resultados obtidos apresentaram conformidade com as recomendações dos guias de validação da Agência Nacional de Vigilância Sanitária (ANVISA, 2003) e do Ministério da Agricultura, Pecuária e Abastecimento (MAPA, 2010), indicando que o método é apropriado para a determinação de ENR na ração medicada. O revestimento da ração medicada tanto com 0,5 % quanto com 2,0 % de polivinilpirrolidona (PVP-K30) reduziu a taxa de lixiviação da ENR na ração para a água, porém essa taxa de redução depende significativamente (p<0,05) da temperatura e do tempo de permanência da ração na água / Abstract: Fish farming in Brazil has grown significantly over the past 20 years, reflected by increased production at high stocking densities. With the intensification of aquaculture, the emergence of outbreaks caused by various etiological agents becomes increasingly frequent, including the bacterial diseases. To combat the agents responsible for those diseases, many antibiotics are used illicitly. Nonetheless, in addition to the possibility of no effectiveness during treatment, they can induce lethality to the animals and cause environmental damage. Currently, Brazil has only two antimicrobials approved for use in aquaculture: florfenicol and oxytetracycline. Enrofloxacin (ENR) is an antibiotic widely used in veterinary medicine for presenting a high potential for efficacy in treating bacterial diseases. However, although in Brazil it is not yet regulated for use in fish farming, many farmers use it unlawfully, being added to the feed or by immersion baths. These procedures favor the drug loss through leaching from the feed, induce changes at the aquatic ecosystem, and endanger consumer and animal health. Possible alternatives to facilitate the administration of ENR, minimizing the problems caused in the environment are the feed coating, one of the oldest processes still exist with great applicability in several pharmaceutical segments. For the coating, polymers must be compatible with the chemical end physic-chemical characteristics of the drug, ensuring homogeneity of the final product and reduction of drug loss over time of feed administration. For this purpose, after coating the medicated feed becomes necessary to evaluate the leaching rate of the drug from the feed. To accomplish this it is required to develop and validate an analytical method that guarantees the determination of the drug content, before and after the leaching process of the medicated feed. The method for quantification of ENR in the feed was based on the technique of high performance liquid chromatography with diode array detector (HPLC-DAD). The method was validated considering the following parameters: linearity, sensitivity, selectivity, intra-day and inter-day precision, accuracy, detection and quantification limits. The results showed compliance with the recommendations from the validation guide of the National Agency for Sanitary Surveillance (ANVISA, 2003) and the Ministry of Agriculture, Livestock and Supply (MAPA, 2010), indicating that the method is suitable for the ENR determination on the medicated feed. The coating of the medicated feed with both: 0.5% and 2.0% polivinilpirrolydone (PVP-K30) reduced the leaching rate of the ENR from the feed to the water. However, the leaching rate reduction depends significantly (p<0.05) on the water temperature, as well as on the time residence of the feed in the water / Mestrado / Ciência de Alimentos / Mestra em Ciência de Alimentos

Les interactions aliment-médicaments nuisant aux processus de libération et/ou à la stabilité de leurs principes actifs doivent être caractérisées en raison de leurs conséquences adverses sur la biodisponibilité orale, l’efficacité thérapeutique et, dans le cas des agents anti infectieux, la sélection d’organismes résistants. Notre étude a évalué la relation entre l'efficacité de la libération in vitro de la chlortétracycline (CTC) et de la lincomycine (LIN) dans le liquide gastrique simulé de porc (LGSP) et la capacité de rétention d'eau (CRE) d’ingrédients couramment utilisés dans l’alimentation des porcs (tourteau de soja (TS), drèche de distillerie sèche avec solubles (DDS) et farine de viande et d'os (FVO), maïs, blé, et seigle), que l’on a fortifié avec 880 ppm de CTC ou 440 ppm de LIN. La CRE des ingrédients différait significativement (p <0,0001) et était maximale avec le TS, aussi bien dans l'eau que le LGSP. Le FVO avait une CRE significativement plus basse dans le LGSP que dans l'eau (p <.0001). Les effets du temps de trempage sur la CRE étaient négligeables pour tous les ingrédients (p> 0,50). La CRE diminue avec l'augmentation de la taille des particules pour tous les aliments, mais leurs relations différaient significativement (p<0.0001). Tous les ingrédients alimentaires testés ont diminué la vitesse et l'étendue de la dissolution des prémélanges de CTC et de LIN. Le CRE était le principal facteur qui a empêché la dissolution des deux médicaments (p <0,0001), tandis que le temps et la teneur en cendres des ingredients favorisaient significativement leur dissolution (p ≤ 0,008). En comparaison des prémélanges dissouts seuls, le DDS et le seigle ont libéré 80% de ces antibiotiques, tandis que le TS, le blé et le maïs en ont libéré entre 40 et 50%. La neutralisation du LGSP au pH intestinal porcin a diminué les proportions dissoutes d’antibiotiques, mais pas significativement (p>0.69). La CRE des ingrédients utilisés dans la fabrication d'aliments médicamenteux serait donc un indicateur prometteur des interactions aliment-prémélange médicamenteux de LIN et de CTC. Afin d'augmenter leur libération et leur potentiel thérapeutique, la formulation des aliments médicamenteux pourrait être améliorée en utilisant des ingrédients alternatifs, dont la CRE est moindre. / Food-drug interactions adversely affecting the release process and the stability of their active ingredients must be characterized because of their adverse consequences on oral bioavailability, therapeutic efficacy and, in the case of antibiotics, selection resistant organisms. Our study evaluated the relationship between the efficiency of the in vitro release of chlortetracycline (CTC) and lincomycin (LIN) in simulated pig gastric fluid (SPGF) and the water-holding capacity (WHC) of feedstuffs commonly used in pig feed (soybean meal (SBM), dry distillers' grain with solubles (DDGS) and meat and bone meal (MBM), corn (gC), wheat (gW), and rye (gR), which it was fortified with 880 ppm CTC or 440 ppm LIN. The WHC of ingredients differed significantly (p <0.0001) among feedstuffs with the highest value for SBM both in water and SPGF and lowest value for MBM. The MBM had a significantly lower WHC in SPGF than in water (p <.0001). The effects of soaking time on WHC were negligible for all feedstuffs (p> 0.50). The WHC decreased with increasing particle size for all feedstuffs, but their relationships differed significantly (p <0.0001). All the tested feedstuffs decreased the rate and extent of dissolution of the CTC and LIN premixes. WHC was the main factor that hindered the dissolution of both drugs (p <0.0001), while the time and ash content of the ingredients significantly favored their dissolution (p ≤ 0.008). Compared to the dissolved premixes alone, DDGS and gR released 80% of these antibiotics, while SBM, gW and gC released between 40% and 50%. Neutralization of SPGF at swine intestinal pH decreased the dissolved proportions of antibiotics, but not significantly (p> 0.69). The WHC of the used feedstuffs in the manufacture of medicated feed would therefore be a promising indicator of the feed-drug interactions of LIN and CTC. To increase their release and therapeutic potential, the formulation of medicated feeds could be improved by using alternative ingredients, with less WHC.

La quantification de l’utilisation des antimicrobiens (UAM) est un élément clé des programmes de surveillance de la résistance aux antimicrobiens. Cette thèse a pour objectif général d’évaluer plusieurs méthodes de quantification de l’UAM dans les fermes laitières québécoises. Plus précisément, elle vise à définir un indicateur adapté au contexte canadien pour rapporter l’UAM chez les bovins, à déterminer le taux d’UAM annuel moyen dans les fermes laitières québécoises et à comparer différentes méthodes de quantification afin d’identifier une méthode potentielle de surveillance de l’UAM dans les fermes laitières québécoises. Une étude observationnelle de cohorte a été menée à partir du recrutement de 101 producteurs laitiers du Québec. Un inventaire des antimicrobiens utilisés a été réalisé pendant un an pour chaque ferme à partir de la collecte (1) des emballages de médicaments utilisés pour traiter les bovins et (2) des factures de meunerie détaillant les quantités d’aliments médicamenteux livrées. Le taux d’UAM a été estimé en nombre de doses définies par 100 vache-années. Les doses définies n’existaient pas pour les bovins au Canada et ont été développées : dose journalière (DDDbovCA) et dose pour un traitement complet (DCDbovCA). Étant donnée l’utilisation de formulations à action prolongée en production laitière (comme les intra-mammaires au tarissement), l’unité DCDbovCA a été privilégiée pour les analyses. Un taux moyen de 537 DCDbovCA/100 vache-années a été observé, soit 537 traitements antibiotiques administrés annuellement dans un troupeau standard de 100 vaches laitières. La voie d’administration intra-mammaire était la plus utilisée. Les antimicrobiens d’importance critique les plus prioritaires en médecine humaine représentaient 17,5% de l’utilisation totale. Une faible proportion de fermes utilisait des antimicrobiens médicalement importants dans l’alimentation des animaux. L’incidence des maladies n’expliquait que partiellement la variance de l’utilisation totale. D’autres facteurs restent à déterminer pour expliquer les pratiques d’UAM dans les fermes laitières québécoises. Les données issues de plusieurs méthodes de quantification ont été comparées aux données de l’étude observationnelle. Pour les médicaments vétérinaires d’une part, le taux d’UAM estimé à partir des factures vétérinaires décrivait de façon presque parfaite le taux d’UAM réel (coefficient de corrélation de concordance, CCC = 0,83) alors que les méthodes utilisant les données du programme gouvernemental « Amélioration de la santé animale au Québec » ou des registres de traitements complétés à la ferme performaient moins bien. Pour les aliments médicamenteux d’autre part, le taux d’UAM estimé à partir des prescriptions vétérinaires pour aliments médicamenteux ou à partir des informations obtenues lors d’une entrevue individuelle avec le producteur corrélait bien le taux d’UAM réel (CCC = 0,66 et 0,73 respectivement). Le projet a permis de quantifier l’UAM annuelle dans les fermes laitières québécoises (par catégorie d’antimicrobiens et voie d’administration) en utilisant un nouvel indicateur de mesure (DCDbovCA). De plus, ce projet démontre la validité des données issues des factures et prescriptions vétérinaires pour quantifier l’UAM dans les troupeaux laitiers québécois. Le logiciel de facturation utilisé par la majorité des médecins vétérinaires praticiens du Québec pourrait servir au développement d’un système provincial de surveillance et de benchmarking de l’UAM. / Quantification of antimicrobial usage (AMU) is a key component of surveillance programs on antimicrobial resistance. The general objective of this thesis was to assess different quantification methods of the AMU in Québec dairy farms. More specifically, the project was designed to define a metric adapted to the Canadian context for AMU reports in cattle, to determine the mean annual AMU rate in Québec dairy herds, and to compare several quantification methods in order to identify a potential method suitable for AMU surveillance in Québec dairy farms. An observational cohort study was conducted from the recruitment of 101 Québec dairy producers. Antimicrobials used to treat dairy cattle were quantified over one year using a garbage can audit involving the collect of (1) veterinary drugs into a receptacle and (2) medicated feed delivered on the farm from feed mills invoices. The AMU rate was estimated in number of defined doses per 100 cow-years. Defined doses were not available in Canada for cattle and were assigned as part of the project: daily doses (DDDbovCA) and course doses (DCDbovCA). Due to usage of long-acting products in dairy cattle (such as intramammary formulations for dry cows), the DCDbovCA unit was preferred for analyses. Overall, an estimated mean of 537 DCDbovCA/100 cow-years was observed, meaning that an average of 537 antimicrobial treatments were administered annually in a standard 100-cow herd. The intramammary route during lactation was the most frequently observed. Highest priority critically important antimicrobials accounted for 17.5% of the total usage. A low proportion of farms used medically important antimicrobials in animal feed. Incidence of diseases explained only partially the variance in total AMU rate. Other factors have to be determined to explain the AMU in Québec dairy farms. Data from several quantification methods were compared to the observational study data. First, for veterinary drugs, the AMU rate estimated from veterinary sales described almost perfectly the actual AMU rate (concordance correlation coefficient, CCC = 0.83), whereas other methods using data from the governmental program “Amélioration de la santé animale au Québec” or from treatment records completed on the farm were not as reliable. Second, for medicated feed, the AMU rate estimated from veterinary prescriptions for medicated feed or from information obtained by individual interviews with producers were well correlated with the actual AMU rate (CCC = 0.66 and 0.73, respectively). Quantification of AMU was successfully performed by antimicrobial category and by route of administration in Québec dairy farms over one year using a newly defined unit of measure (DCDbovCA). This project demonstrates the validity of the data extracted from veterinary invoices and prescriptions to quantify the AMU in Québec dairy herds. The billing software used by most of Québec veterinary practitioners could be used to develop a monitoring and benchmarking system of the AMU at the provincial level.