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Mika Tuomola - One of the best experts on this subject based on the ideXlab platform.
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rapid screening of Narasin residues in poultry plasma by time resolved fluoroimmunoassay
Analytica Chimica Acta, 2005Co-Authors: Pekka Peippo, Timo Lovgren, Mika TuomolaAbstract:Abstract A simple and rapid time-resolved fluoroimmunoassay (TR-FIA) method has been developed for the screening of Narasin in poultry plasma. This method involves only a dilution of sample and competitive microwell plate immunoassay combined with the measurement of time-resolved fluorescence. The performance of the assay has been confirmed by validation according to Commission’s Decision 2002/657/EC. Decision limit and detection capability of the assay have been 1.2 and 1.5 ng ml−1, respectively. Narasin recovery from plasma has ranged from 101.0 to 121.3%. In the feeding study broiler chickens have been fed Narasin at a dose rate of 0, 3.5 and 70 mg kg−1 feed for 3-week period and the concentration of Narasin in the plasma and muscle of broilers have been studied by the TR-FIA. Feeding with 70 mg kg−1 and no withdrawal period resulted in a very high Narasin levels in blood, and the artificial contamination level of feed (3.5 mg kg−1) was also detected by the analysis of blood samples. A relationship was observed between the concentrations of Narasin in plasma and breast muscle (R2 = 0.83) and leg muscle (R2 = 0.90). These results suggest that the analysis of poultry blood samples could be used as a predictor of Narasin residues in muscle.
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rapid time resolved fluoroimmunoassay for the screening of Narasin and salinomycin residues in poultry and eggs
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Pekka Peippo, Timo Lovgren, Virve Hagren, Mika TuomolaAbstract:: Anticoccidial drugs are extensively used in the poultry industry to control the infection of the single-cell protozoa of the genus Eimeria. The most commonly used coccidiostats in poultry are the polyether ionophores such as Narasin and salinomycin. This paper presents a rapid and simple method for the screening of residues of these two coccidiostatic compounds in poultry and eggs. The method is based on time-resolved fluoroimmunoassay. Sample preparation of eggs consists only of one extraction and evaporation step, and a solid phase extraction step is needed only for the muscle sample preparation. Mean recoveries were 91.0% from muscle tissue and 81.1% from eggs for both Narasin and salinomycin. The performance of the assay was evaluated only for Narasin because salinomycin had a cross-reactivity of 100% in the assay, and the recoveries of the compounds were not significantly different (P >0.05). The limits of detection [mean + 3 x standard deviation (SD)] of Narasin were 0.56 and 0.28 microg/kg, and the limits of quantification (mean + 9 x SD) were 1.80 and 0.57 microg/kg for muscle and eggs, respectively. The coefficients of variation (CV) of the interassay precision of the method, evaluated by five replicate analyses of muscle samples spiked with 2 microg/kg of Narasin and egg samples spiked with 1 microg/kg of Narasin, were 4.1 and 6.4%, respectively. The CVs of intra-assay precision tests, determined by 10 replicate analyses at the above-mentioned concentration levels, were 3.8 and 4.5%, respectively.
Pekka Peippo - One of the best experts on this subject based on the ideXlab platform.
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rapid screening of Narasin residues in poultry plasma by time resolved fluoroimmunoassay
Analytica Chimica Acta, 2005Co-Authors: Pekka Peippo, Timo Lovgren, Mika TuomolaAbstract:Abstract A simple and rapid time-resolved fluoroimmunoassay (TR-FIA) method has been developed for the screening of Narasin in poultry plasma. This method involves only a dilution of sample and competitive microwell plate immunoassay combined with the measurement of time-resolved fluorescence. The performance of the assay has been confirmed by validation according to Commission’s Decision 2002/657/EC. Decision limit and detection capability of the assay have been 1.2 and 1.5 ng ml−1, respectively. Narasin recovery from plasma has ranged from 101.0 to 121.3%. In the feeding study broiler chickens have been fed Narasin at a dose rate of 0, 3.5 and 70 mg kg−1 feed for 3-week period and the concentration of Narasin in the plasma and muscle of broilers have been studied by the TR-FIA. Feeding with 70 mg kg−1 and no withdrawal period resulted in a very high Narasin levels in blood, and the artificial contamination level of feed (3.5 mg kg−1) was also detected by the analysis of blood samples. A relationship was observed between the concentrations of Narasin in plasma and breast muscle (R2 = 0.83) and leg muscle (R2 = 0.90). These results suggest that the analysis of poultry blood samples could be used as a predictor of Narasin residues in muscle.
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rapid time resolved fluoroimmunoassay for the screening of Narasin and salinomycin residues in poultry and eggs
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Pekka Peippo, Timo Lovgren, Virve Hagren, Mika TuomolaAbstract:: Anticoccidial drugs are extensively used in the poultry industry to control the infection of the single-cell protozoa of the genus Eimeria. The most commonly used coccidiostats in poultry are the polyether ionophores such as Narasin and salinomycin. This paper presents a rapid and simple method for the screening of residues of these two coccidiostatic compounds in poultry and eggs. The method is based on time-resolved fluoroimmunoassay. Sample preparation of eggs consists only of one extraction and evaporation step, and a solid phase extraction step is needed only for the muscle sample preparation. Mean recoveries were 91.0% from muscle tissue and 81.1% from eggs for both Narasin and salinomycin. The performance of the assay was evaluated only for Narasin because salinomycin had a cross-reactivity of 100% in the assay, and the recoveries of the compounds were not significantly different (P >0.05). The limits of detection [mean + 3 x standard deviation (SD)] of Narasin were 0.56 and 0.28 microg/kg, and the limits of quantification (mean + 9 x SD) were 1.80 and 0.57 microg/kg for muscle and eggs, respectively. The coefficients of variation (CV) of the interassay precision of the method, evaluated by five replicate analyses of muscle samples spiked with 2 microg/kg of Narasin and egg samples spiked with 1 microg/kg of Narasin, were 4.1 and 6.4%, respectively. The CVs of intra-assay precision tests, determined by 10 replicate analyses at the above-mentioned concentration levels, were 3.8 and 4.5%, respectively.
Timo Lovgren - One of the best experts on this subject based on the ideXlab platform.
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rapid screening of Narasin residues in poultry plasma by time resolved fluoroimmunoassay
Analytica Chimica Acta, 2005Co-Authors: Pekka Peippo, Timo Lovgren, Mika TuomolaAbstract:Abstract A simple and rapid time-resolved fluoroimmunoassay (TR-FIA) method has been developed for the screening of Narasin in poultry plasma. This method involves only a dilution of sample and competitive microwell plate immunoassay combined with the measurement of time-resolved fluorescence. The performance of the assay has been confirmed by validation according to Commission’s Decision 2002/657/EC. Decision limit and detection capability of the assay have been 1.2 and 1.5 ng ml−1, respectively. Narasin recovery from plasma has ranged from 101.0 to 121.3%. In the feeding study broiler chickens have been fed Narasin at a dose rate of 0, 3.5 and 70 mg kg−1 feed for 3-week period and the concentration of Narasin in the plasma and muscle of broilers have been studied by the TR-FIA. Feeding with 70 mg kg−1 and no withdrawal period resulted in a very high Narasin levels in blood, and the artificial contamination level of feed (3.5 mg kg−1) was also detected by the analysis of blood samples. A relationship was observed between the concentrations of Narasin in plasma and breast muscle (R2 = 0.83) and leg muscle (R2 = 0.90). These results suggest that the analysis of poultry blood samples could be used as a predictor of Narasin residues in muscle.
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rapid time resolved fluoroimmunoassay for the screening of Narasin and salinomycin residues in poultry and eggs
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Pekka Peippo, Timo Lovgren, Virve Hagren, Mika TuomolaAbstract:: Anticoccidial drugs are extensively used in the poultry industry to control the infection of the single-cell protozoa of the genus Eimeria. The most commonly used coccidiostats in poultry are the polyether ionophores such as Narasin and salinomycin. This paper presents a rapid and simple method for the screening of residues of these two coccidiostatic compounds in poultry and eggs. The method is based on time-resolved fluoroimmunoassay. Sample preparation of eggs consists only of one extraction and evaporation step, and a solid phase extraction step is needed only for the muscle sample preparation. Mean recoveries were 91.0% from muscle tissue and 81.1% from eggs for both Narasin and salinomycin. The performance of the assay was evaluated only for Narasin because salinomycin had a cross-reactivity of 100% in the assay, and the recoveries of the compounds were not significantly different (P >0.05). The limits of detection [mean + 3 x standard deviation (SD)] of Narasin were 0.56 and 0.28 microg/kg, and the limits of quantification (mean + 9 x SD) were 1.80 and 0.57 microg/kg for muscle and eggs, respectively. The coefficients of variation (CV) of the interassay precision of the method, evaluated by five replicate analyses of muscle samples spiked with 2 microg/kg of Narasin and egg samples spiked with 1 microg/kg of Narasin, were 4.1 and 6.4%, respectively. The CVs of intra-assay precision tests, determined by 10 replicate analyses at the above-mentioned concentration levels, were 3.8 and 4.5%, respectively.
O Nilsson - One of the best experts on this subject based on the ideXlab platform.
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genetic diversity among vre isolates from swedish broilers with the coincidental finding of transferrable decreased susceptibility to Narasin
Journal of Applied Microbiology, 2012Co-Authors: O Nilsson, Christina Greko, Bjorn Bengtsson, S EnglundAbstract:Aims: In this study, the molecular diversity among clones of vancomycin resistant Enterococcus faecium with vanA gene (VRE) is investigated. The aims were to better understand why one clone is predominant in Swedish broiler production and to better assess the potential for zoonotic gene transfer from the different clones. Methods and Results: Twenty-six isolates were separated into 11 clones. Vancomycin resistance was transferrable from the predominant and five minority clones. Decreased susceptibility to Narasin was co-transferred with vancomycin resistance in four clones, including the predominant. The plasmid addiction system axe-txe was not detected, and the ω-e-ζ system was detected in one of the minority clones but was not co-transferred with vancomycin resistance. Conclusions: The results do not explain why one clone is predominant among VRE in Swedish broiler production but confirms the potential for zoonotic spread of vancomycin resistance genes. The near absence of investigated plasmid addiction systems indicates that they do not play an important role in the epidemiology of VRE in Swedish broiler production. The finding that decreased susceptibility to Narasin can be co-transferred with the vanA gene indicates that the use of Narasin might play a role in the persistence of vancomycin resistance in enterococci colonizing Swedish broilers. Significance and Impact of the Study: This is, to our knowledge, the first report of transferrable decreased susceptibility to Narasin.
Alexandre Vaz Pires - One of the best experts on this subject based on the ideXlab platform.
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effects of supplementation with Narasin salinomycin or flavomycin on performance and ruminal fermentation characteristics of bos indicus nellore cattle fed with forage based diets
Journal of Animal Science, 2021Co-Authors: Arnaldo C Limede, Alexandre A Miszura, Jose P R Barroso, Lairana A Sardinha, Daniel M Polizel, Bruno I Cappellozza, Andre S Martins, Rodrigo S Marques, Marcelo Baggio, Alexandre Vaz PiresAbstract:The aim of the present study was to evaluate the inclusion of Narasin, salinomycin, or flavomycin for 140 d on ruminal fermentation parameters, apparent nutrient digestibility, and performance of Nellore cattle offered a forage-based diet. In experiment 1, 32 rumen-cannulated Bos indicus Nellore steers [initial body weight (BW) = 220 ± 12.6 kg] were assigned to individual pens in a randomized complete block design according to their initial shrunk BW. Within block, animals were randomly assigned to 1 of 4 treatments: (1) forage-based diet without feed additives (CON; n = 8), (2) CON diet plus 13 ppm of Narasin (NAR; n = 8), (3) CON diet plus 20 ppm of salinomycin (SAL; n = 8), or (4) CON diet plus 3 ppm of flavomycin (FLA; n = 8). The experimental period lasted 140 d and was divided into 5 periods of 28 d each. The inclusion of feed additives did not impact (P ≥ 0.17) dry matter intake (DMI), nutrient intake, and apparent total tract digestibility of nutrients. Nonetheless, steers fed NAR had lower (P 0.20) between CON, SAL, and FLA. Consequently, NAR steers had the lowest (P 0.18) among CON, SAL, and FLA. Total volatile fatty acids were greater (P 0.67) among NAR vs. CON and SAL vs. FLA. In experiment 2, 164 Nellore bulls (initial shrunk BW = 299 ± 2.5 kg) were assigned to feedlot pens for 140 d in a randomized complete block design. Within block (n = 10), animals were randomly assigned to the same treatments used in experiment 1. Average daily gain was greater (P 0.12) between CON, SAL, and FLA bulls. Bulls fed NAR had greater (P 0.26) between CON, SAL, and FLA bulls. Feed efficiency, however, was not impacted (P = 0.51) by any feed additives used herein. Collectively, Narasin was the only feed additive that benefited performance and ruminal fermentation of Nellore animals fed a forage-based diet.
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residual effect of Narasin on ruminal fermentation characteristics in lambs
Livestock Science, 2020Co-Authors: Leticia Pasqualino, Gabriela B Oliveira, Alexandre A Miszura, Jose P R Barroso, Arnaldo C Limede, Lairana A Sardinha, Janaina S Biava, Evandro Maia Ferreira, Alexandre Vaz Pires, Daniel M PolizelAbstract:ABSTRACT This study aimed to evaluate the effect of Narasin withdrawal on wethers ruminal fermentation characteristics. Four wethers cannulated at the rumen were subjected to a 4 × 4 Latin Square experimental design. The trial lasted 144 days, divided into 4 periods of 36 days each. The diet was composed by 950 g/kg of coastcross hay and 50 g/kg of ground corn, used as a carrier for the Narasin. The experimental diets were defined by frequency of Narasin offer: 1) no feed additives (N0); 2) 13 mg of Narasin/kg of DM every 24 hours (N13); 3) 26 mg of Narasin/kg of DM every 48 hours (N26), and 4) 39 mg of Narasin/kg of DM every 72 hours (N39). The Narasin was offered for 25 days, and at the last 11 days of each period, all the animals received the same proportion of forage and concentrate, but without Narasin inclusion (withdrawal period). Last day of Narasin offering was denominated day 0 and the first day of withdrawal day 1. The fed offer and orts were daily recorded to determine de DMI and nutrient intake. Ruminal fluid was collected 6 hours after concentrate offering from d0 to d11 to determine ruminal pH, SCFA and ammonia nitrogen. There was no difference for dry matter intake among treatments after Narasin withdrawal. There was no treatment and day interaction for total SCFA concentration, molar proportion of acetate, butyrate, isobutyrate, valerate, isovalerate and rumen pH. Treatment and day interaction after Narasin withdrawal interactions was observed for molar proportion of propionate (P
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use of Narasin in diets for lactating ewes
Small Ruminant Research, 2020Co-Authors: Rhaissa Garcia De Assis, Janaina S Biava, Alexandre Vaz Pires, Daniel M Polizel, Terezinha Teixeira De Souza, Thamires U Sturion, Alejandro E Relling, Evandro Maia FerreiraAbstract:ABSTRACT The objective of the present study was to evaluate the effect of different doses of Narasin on dry matter intake (DMI), milk production and composition in ewes and growth performance of their lambs. Forty crossbred lactating ewes Dorper vs. Santa Ines (54.4 ± 1.7 kg of initial BW; mean ± SD) were penned individually with their lambs and used in a randomized complete block design with 10 blocks and 4 treatments. Ewes were fed a basal diet (168 ± 0.003 g/kg DM of CP) containing 50% concentrate and 50% Brachiaria brizantha hay. The treatments were as follows: 0 N - control diet (basal diet without addition Narasin); 13 N - addition of 13 mg/kg DM of Narasin; 20 N - addition of 20 mg/kg DM of Narasin; 27 N - addition of 27 mg/kg DM of Narasin. Once a week, from the second to tenth week of lactation (weaning time), ewes were separated from their lambs, injected with oxytocin, and mechanically milked to empty mammary gland. After 3 hours, the same procedure was repeated, milk production was recorded and samples collected for milk composition analysis. Ewes were weighed for 3 consecutive days at the beginning and end of the experiment. Lambs growth performance was evaluated weekly. The data were analyzed using a linear or quadratic polynomial contrast in SAS. There was a quadratic effect (P = 0.03) of Narasin on milk production, in which ewes fed the diet containing 13 mg/kg DM had the highest production (194.9 g/3 hours) Narasin inclusion decreased linearly the percentage of protein (P = 0.01), non-fat solids (P = 0.03), and SCC (P = 0.04) in milk. The fat, lactose and total solids content were not affected by treatments. There was a quadratic effect (P = 0.05) of Narasin doses on concentrate intake by the lambs, in which the lowest intake was observed for lambs from ewes fed N13. The supply of Narasin did not affect the ADG and final BW of the lambs. In conclusion, the use of 13 mg/kg DM of Narasin was the best concentration in diets containing 50% forage and 50% concentrate for lactating ewes, due to positive effect on milk production. The inclusion of values higher than 20 mg/kg DM of Narasin is not recommended, because this content drastically reduced DMI and milk production, resulting in greater concentrate intake by lambs with no effect on ADG and final BW.
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milk yield and composition from ewes fed diets containing Narasin and their lambs performance
Translational animal science, 2020Co-Authors: Lairana A Sardinha, Gabriela B Oliveira, Alexandre A Miszura, Jose P R Barroso, Arnaldo C Limede, Evandro Maia Ferreira, R S Marques, Andre S Martins, Marcos V C Ferraz, Alexandre Vaz PiresAbstract:The changes promoted by feed additives in ruminal fermentation, especially increasing the availability of propionate, can improve the energy balance of an animal, which is of great importance in the lactation period. This trial aimed to evaluate the inclusion of Narasin in the diet of lactating ewes on milk yield, composition, dry matter intake (DMI), and plasma metabolites of the ewes and growth rate of lambs. Thirty-two lactating ewes (59.0 ± 2.42 kg) were assigned to a randomized complete block design. The experimental diets contained 500 g/kg of dry matter (DM) of coast cross (Cynodon dactylon (L.) Pers) hay and 500 g/kg DM of concentrate, and the treatments were: N0-no Narasin inclusion; N13-inclusion of 13 mg of Narasin/kg DM. Once a week, from week 2 to 10 of lactation, ewes were separated from their lambs, injected with oxytocin, and milked mechanically to empty the udder. After 3 h, the milk production was recorded, using the same procedure, and sampled to evaluate the composition. The blood samples were taken weekly, 4 h after feeding. The average daily gain (ADG) and starter DMI of the lambs were evaluated weekly from week 2 to 12 of age. The inclusion of Narasin did not affect (P = 0.93) DMI of ewes; however, it increased milk production (P 0.05). The results showed that the inclusion of 13 mg of Narasin/kg DM improved the milk production and FE of the ewes without altering the composition of the milk. The lower initial consumption of concentrate by N13 lambs before weaning was caused by the higher production of milk. The results obtained in the present study demonstrate the possible productive gain with the inclusion of Narasin in diets for lactating ewes.
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effects of Narasin supplementation on dry matter intake and rumen fermentation characteristics of bos indicus steers fed a high forage diet
Translational animal science, 2020Co-Authors: Daniel M Polizel, Gabriela B Oliveira, Alexandre A Miszura, Jose P R Barroso, Bruno I Cappellozza, Fernanda Hoe, Catarina N Lopes, L G M Gobato, Alexandre Vaz PiresAbstract:This study evaluated the effects of Narasin on intake and rumen fermentation characteristics of Bos indicus steers offered a high-forage diet for 140 d. On day 0 of the study, 30 rumen-fistulated Nellore steers [initial body weight (BW) = 281 ± 21 kg] were assigned to 30 individual pens in a randomized complete block design according to their initial BW. Animals were randomly assigned to 1 of the 3 treatments: 1) forage-based diet without Narasin (CONT; n = 10), 2) CONT diet plus 13 ppm of Narasin (13NAR; n = 10), and 3) CONT diet plus 20 ppm of Narasin (20NAR; n = 10). The forage used was Tifton-85 (Cynodon dactylon spp.), whereas the carrier for Narasin was a 50:50 mixture of soybean hull:corn. The experimental period was divided into 5 periods of 28 d each. Throughout the experimental period, total dry matter intake (DMI) was recorded daily, whereas mineral salt intake was recorded weekly. Blood and ruminal fluid samples were collected on day 0 (prior to treatment feeding), 28, 56, 84, 112, and 140 of the study. Moreover, total tract apparent nutrient digestibility was performed for a 5-d period every 28 d. No treatment effects were observed on forage, mineral, concentrate, or total DMI (P ≥ 0.22). Nonetheless, 13NAR tended to have a greater mineral intake vs. 20NAR cohorts (P = 0.08) Narasin-supplemented animals had reduced rumen acetate, Ac:Pr ratio, as well as greater (P ≤ 0.02) rumen propionate concentrations vs. CONT cohorts. Moreover, 13NAR increased rumen propionate and decreased butyrate, Ac:Pr vs. 20NAR cohorts (P ≤ 0.01). Throughout the experimental period, Narasin-supplemented animals had reduced ammonia concentrations vs. CONT cohorts (P < 0.01), whereas no differences were observed between 13NAR and 20NAR (P = 0.80). No treatment or dose effects were observed (P ≥ 0.23) on DM, organic matter (OM), protein, neutral detergent fiber (NDF), acid detergent fiber (ADF), and mineral digestibility. Animals fed 13NAR had a reduced mean plasma urea concentration vs. CONT cohorts (P = 0.03), whereas no further differences were observed (P ≥ 0.12). In summary, Narasin supplementation to beef steers offered a high-forage diet did not impact forage, mineral, and total DMI, as well as nutrient digestibility, whereas rumen fermentation characteristics, rumen ammonia, and plasma urea concentrations were positively impacted and lasted throughout the experimental period. Additionally, 13 ppm of Narasin resulted in a reduced Ac:Pr ratio and rumen ammonia when compared to animals supplemented with 20 ppm.
