Assessing the depletion of lincomycin in feathers from treated broiler chickens: a comparison with the concentration of its residues in edible tissues.

Lincomycin is the first antimicrobial agent described for the lincosamide class and it is commonly used for the treatment of infectious enteric and respiratory diseases in poultry. Maximum residue limits (MRLs) in edible tissues have been established for this antimicrobial, however, no regulation has been proposed yet for by-products that are not intended for direct human consumption. Feathers are a by-product from poultry farming that might be used as an ingredient for diets fed to other farm animal species. The presence of antimicrobial residues in them is not monitored in spite of the fact that several studies have proved that they can persist in feathers. Currently though, no evidence has been presented regarding the behaviour of lincomycin in this matrix. Hence, this work intended to assess the depletion of lincomycin residues in feathers of birds treated with therapeutic doses and compare them with those detected in muscle and liver samples. Samples were collected for several days after ceasing treatment from a group of broiler chickens treated with a 25% lincomycin formulation. Methanol and Florisil® columns were used to extract and retain the analyte, and samples were analysed using a triple quadrupole mass spectrometer (API 5500, AB SCIEX™). On day 1 after ceasing treatment, average concentrations of lincomycin detected in feather samples reached up to 8582 µg kg-1 and by day 16, these had only declined by 63%, to an average of 3138 µg kg-1. Lincomycin residues were detected in feathers at every sampling point, even after they were not detectable in edible tissues. Depletion time was 98 days for feathers, considering the LOQ established for the methodology as cut-off value for the calculations. Data showed that lincomycin is highly persistent in feathers, which may result in this matrix becoming a re-entry route for its residues into the food chain.

Chito-oligosaccharide as growth promoter replacement for weaned piglets: performance, morphometry, and immune system / Quitooligossacarídeo como substituto aos promotores de crescimento para leitões desmamados: desempenho, morfometria e imunidade

The objective of this study was to evaluate the chito-oligosaccharide (COS) against two growth promoter antibiotics, colistin and lincomycin, with respect to growth performance, incidence of diarrhea, visceral characteristics, morphometry, and serum immunoglobulin levels (IgA, IgG, and IgM). A total of 96 Pen Ar Lan® piglets (48 barrows and 48 females), weaned at 17 days and with body weight (BW) 5.33 ± 0.37 kg, were subjected to the evaluation of growth performance and serum. Twenty-four animals, females, 35-day-old and with BW 6.86 ± 0.64 kg, were used for the assessment of histology and visceral organ weight. The three treatments were a basic diet formulation supplemented with COS (100 mg kg-1), colistin (40 mg kg-1), or lincomycin (4.4 mg kg-1). The antibiotic treatments showed higher average daily gain (ADG) than COS treatment during the period of 49 to 63 days; whereas the feed conversion ratio (FCR) was higher and incidence of diarrhea was lower for the colistin treatment than for other treatments. The spleen weight and the small intestinal length were higher and duodenal pH was lower for COS than for antibiotics. Morphometry indicated greater villus height and higher ratio of villus height to crypt depth with colistin than with COS and a lower lesion score compared with other treatments. The serum IgA concentration was higher for COS in 35-day-old piglets. According to the results, COS wasnot efficient to replace colistin as a growth promoter for piglets weaned at 17 days; however, the resultsrelated to the immune system suggested that COS is a potentially promising product during weaning.(AU)

Realizou-se este trabalho com o objetivo de avaliar o quitooligossacarídeo (QOS) frente a dois antibióticos utilizados como promotores de crescimento, a colistina e lincomicina, quanto ao desempenho, frequência de diarreia, características viscerais, morfometria e imunoglobulinas séricas, IgA, IgG e IgM. Foram utilizados 96 leitões de genética Pen Ar Lan®, desmamados com idade média de 17 dias e peso de 5,33 ± 0,369 kg para avaliação de desempenho e imunoglobulinas séricas. Para a avaliação histológica e peso dos órgãos, foram utilizados 24 animais com idade de 35 dias e peso de 6,86 ± 0,64 kg. Os três tratamentos consistiram em uma dieta basal acrescida de QOS (100 mg Kg -1), dieta basal com colistina 40 mg Kg -1 e dieta basal com lincomicina 4,4 mg Kg -1. Para o desempenho, os antibióticos apresentaram melhor ganho diário de peso (GPD) dos 49 aos 63 dias de idade em relação ao QOS e a conversão alimentar (CA) foi melhor para a colistina em comparação com os demais tratamentos, além disso apresentou menor incidência de diarreia aquosa quando comparada com os outros tratamentos. Para as vísceras, observou-se aumento do peso relativo do baço, maior comprimento do intestino delgado e menor pH duodenal para os leitões que receberam QOS em relação aos antibióticos. A morfometria indicou maior altura de vilosidades e melhor relação vilos/cripta para a colistina em relação ao QOS e menor escore lesional em relação aos demais tratamentos. A concentração sérica de imunoglobulinas apontou uma maior concentração de IgA para o QOS aos 35 dias. Frente aos resultados observados, embora o QOS tenha promovido estímulos sobre o sistema imune do animal, este não foi eficiente parasubstituir a colistina como promotor de crescimento para leitões desmamados com 17 dias de idade.(AU)

Chito-oligosaccharide as growth promoter replacement for weaned piglets: performance, morphometry, and immune system / Quitooligossacarídeo como substituto aos promotores de crescimento para leitões desmamados: desempenho, morfometria e imunidade

The objective of this study was to evaluate the chito-oligosaccharide (COS) against two growth promoter antibiotics, colistin and lincomycin, with respect to growth performance, incidence of diarrhea, visceral characteristics, morphometry, and serum immunoglobulin levels (IgA, IgG, and IgM). A total of 96 Pen Ar Lan® piglets (48 barrows and 48 females), weaned at 17 days and with body weight (BW) 5.33 ± 0.37 kg, were subjected to the evaluation of growth performance and serum. Twenty-four animals, females, 35-day-old and with BW 6.86 ± 0.64 kg, were used for the assessment of histology and visceral organ weight. The three treatments were a basic diet formulation supplemented with COS (100 mg kg-1), colistin (40 mg kg-1), or lincomycin (4.4 mg kg-1). The antibiotic treatments showed higher average daily gain (ADG) than COS treatment during the period of 49 to 63 days; whereas the feed conversion ratio (FCR) was higher and incidence of diarrhea was lower for the colistin treatment than for other treatments. The spleen weight and the small intestinal length were higher and duodenal pH was lower for COS than for antibiotics. Morphometry indicated greater villus height and higher ratio of villus height to crypt depth with colistin than with COS and a lower lesion score compared with other treatments. The serum IgA concentration was higher for COS in 35-day-old piglets. According to the results, COS wasnot efficient to replace colistin as a growth promoter for piglets weaned at 17 days; however, the resultsrelated to the immune system suggested that COS is a potentially promising product during weaning.

Realizou-se este trabalho com o objetivo de avaliar o quitooligossacarídeo (QOS) frente a dois antibióticos utilizados como promotores de crescimento, a colistina e lincomicina, quanto ao desempenho, frequência de diarreia, características viscerais, morfometria e imunoglobulinas séricas, IgA, IgG e IgM. Foram utilizados 96 leitões de genética Pen Ar Lan®, desmamados com idade média de 17 dias e peso de 5,33 ± 0,369 kg para avaliação de desempenho e imunoglobulinas séricas. Para a avaliação histológica e peso dos órgãos, foram utilizados 24 animais com idade de 35 dias e peso de 6,86 ± 0,64 kg. Os três tratamentos consistiram em uma dieta basal acrescida de QOS (100 mg Kg -1), dieta basal com colistina 40 mg Kg -1 e dieta basal com lincomicina 4,4 mg Kg -1. Para o desempenho, os antibióticos apresentaram melhor ganho diário de peso (GPD) dos 49 aos 63 dias de idade em relação ao QOS e a conversão alimentar (CA) foi melhor para a colistina em comparação com os demais tratamentos, além disso apresentou menor incidência de diarreia aquosa quando comparada com os outros tratamentos. Para as vísceras, observou-se aumento do peso relativo do baço, maior comprimento do intestino delgado e menor pH duodenal para os leitões que receberam QOS em relação aos antibióticos. A morfometria indicou maior altura de vilosidades e melhor relação vilos/cripta para a colistina em relação ao QOS e menor escore lesional em relação aos demais tratamentos. A concentração sérica de imunoglobulinas apontou uma maior concentração de IgA para o QOS aos 35 dias. Frente aos resultados observados, embora o QOS tenha promovido estímulos sobre o sistema imune do animal, este não foi eficiente parasubstituir a colistina como promotor de crescimento para leitões desmamados com 17 dias de idade.

Statistical Modelling and Optimization of Fermentation Medium for Lincomycin Production by Streptomyces lincolnensis Immobilized Cells

ABSTRACT Response surface methodology was used to optimize lincomycin production by Streptomyces lincolnensis NRRL ISP-5355 in submerged fermentation. Screening of fermentation medium components to find their relative effect on lincomycin production was done using Plackett-Burman design. Malt extract, dextrin, soluble starch and (NH4)2SO4 were the most significant nutrient influenced on lincomycin production. Central composite design was applied to determine optimal concentrations of these factors and the effect of their mutual interactions. The interaction between soluble starch and (NH4)2SO4 was found to enhance the production, whereas malt extract and dextrin exhibited an influence independent from the other two factors. Using this statistical optimization method, maximum lincomycin concentration of 1345 μg/ml was obtained which represented a 40.5 % increase in titer than that acquired from the non-optimized medium. This statistically optimized medium was employed for lincomycin production through immobilization of Streptomyces lincolnensis by adsorption on synthetic cotton fibers. Immobilization technique improved the concentration to 1350 μg/ml higher than that produced from free cells cultures and could be maintained for longer than 17 days in a repeated batch system.

Pruebas de sensibilidad frente a agentes anti microbianos en cepas de Brachyspira pilosicoli aisladas a partir de ponedoras comerciales en Colombia / Antimicrobial susceptibility test in Brachyspira pilosicoli strains isolated from commercial layers farms in Colombia

Las espiroquetas intestinales del género Brachyspira ocasionan enfermedades importantes en porcinos y aves. Se ha evidenciado un problema de incremento en la presentación de cepas resistentes a los antimicrobianos utilizados normalmente para tratar las espiroquetosis intestinales en porcinos, y esto podría ser aplicable a los aislamientos de aves. Hay muypocos reportes de sensibilidad antimicrobiana in vitro de cepas de Brachyspira spp. aisladas en aves. En este estudio se evaluó la sensibilidad de doce aislamientos de Brachyspira pilosicoli obtenidos de granjas de ponedoras comerciales a los agentes antimicrobianos tiamulina, tilosina y lincomicina, y se estableció la concentración mínima inhibitoria (CMI)mediante la técnica de dilución en agar. Todas las bacterias analizadas fueron sensibles a tiamulina (CMI≤0,1 μg/ml) y lincomicina (CMI 1 μg/ml) y resistentes a tilosina (CMI 5 μg/ml).

Intestinal Spirochaetes of the genus Brachyspira cause important diseases in swine and poultry. An increasing problem in the presentation of resistant strains to the antimicrobial drugs usually used to treat the intestinal spirochaetosis in swine has been evidenced and this could be applicable to the isolations from poultry. There are very few reports of in vitro antimicrobialsusceptibility of Brachyspira spp. isolated from birds. In this study the antimicrobial susceptibility of twelve Brachyspira pilosicoli isolates obtain from commercial layers was evaluated against tiamulin, tylosin and lincomycin establishing the Minimum Inhibitory Concentration (MIC) by agar dilution technique. All bacteria analyzed were sensitive to tiamulin (MIC ≤0,1μg/ml), and lincomycin (MIC 1μg/ml) and resistant to tylosin (MIC 5μg/ml).

Effect of lincomycin treatment of root surface in dental replantation: a study in rats / Efeito da lincomicina como tratamento da superfície radicular no reimplante de dentes: estudo em ratos

Purpose: The purpose of studies on antibiotics used topically on the root surface of avulsed teeth is to evaluate their antiresorptive properties which favor the repair of the periodontal ligament and the reestablishment of the dentoalveolar articulation. The aim of the present study was to determine the effect of lincomycin treatment of the root surface on tooth replantation. Methods: Ten rats were distributed into two groups (I - control; II - experimental). The right maxillary incisor of the animals was extracted and stored in milk for 30 min. The tooth in group I was rinsed with normal saline and replanted; in group II, the incisor was immersed in lincomycin for 5 min before replantation. The animals were euthanized on the 21st day postoperative. The right hemimaxilla was submitted to histological sectioning and stained with H&E for microscopic evaluation. Results: Group I: the periodontal ligament appeared dispersed, with moderate to intense lymphoplasmacytic infiltrate, and dentoalveolar articulation was not reestablished. Group II: complete repair of the ligament was evident, and there were few inflammatory cells and small areas of inflammatory resorption and ankylosis. Conclusion: The use of lincomycin allowed the repair of the periodontal ligament and reduced inflammation. There were still areas of inflammatory resorption and ankylosis.

Objetivo: Estudos sobre antibióticos usados topicamente na superfície radicular de dentes avulsionados buscam avaliar suas propriedades anti-reabsortivas que favoreçam o reparo do ligamento periodontal e o restabelecimento da articulação dentoalveolar. Neste mesmo propósito, esta pesquisa avaliou o efeito da lincomicina na superfície radicular, antes do reimplante. Metodologia: Dez ratos foram distribuídos em dois grupos de 05 animais (I - controle e II - experimental). O incisivo superior direito dos animais foi extraído e estocado em leite por 30 min. Em seguida, no grupo I, os dentes foram irrigados com soro fisiológico e reimplantados; no grupo II, os incisivos foram imersos em lincomicina por 5 min, antes do reimplante. Os animais foram eutanasiados no 21º dia pós-operatório e a hemimaxila direita submetida a cortes histológicos, corados em HE, para avaliação microscópica. Resultados: No grupo I, o ligamento periodontal apresentou-se disperso, com infiltrado linfoplasmocitário moderado a intenso e a articulação dentoalveolar não foi restabelecida; no grupo II, notou-se completo reparo do ligamento, poucas células inflamatórias e pequenas áreas de reabsorção inflamatória e anquilose. Conclusões: O uso tópico da lincomicina no tratamento da superfície radicular promoveu o reparo do ligamento periodontal, reduziu o processo inflamatório, mas ainda foram observadas áreas de reabsorção inflamatória e anquilose.