自2005年以降，我國針對是否開放含萊克多巴胺畜產品進口之問題即屬多事之秋，其主因係在食品添加物專家委員會（Joint FAO/WHO Expert Committee on Food Additives，簡稱JECFA）所擬每日容許攝食量下，國際上之相關科學研究無法確切證明萊克多巴胺是否完全安全，抑或其可能對於人體造成之危害及程度，因此多數肉品出口國仍常於家畜飼養過程中添加萊克多巴胺於飼料中，藉以增加畜產品之瘦肉比例並提升經濟效率；另一方面，由於不肖業者違法使用乙型受體素（如克崙特羅、沙丁胺醇）導致人體中毒的案件時有所聞，影響民眾對於畜產品的消費意願及產業發展，是故雖然萊克多巴胺之毒性相較於其他乙型受體素為低，惟受他種毒素高出數倍的乙型受體素之累，在我國自2006年起亦屬禁用之列。在國際食品標準委員會（Codex Alimentarius Commission，簡稱Codex委員會）於去（2012）年以普通多數決之方式制定萊克多巴胺的國際標準後，我國遂修訂食品衛生管理法第11條（2013年新法第15條）、第17-1條 （新法第25條）及動物用藥殘留標準第3條，並公告農防字第1011473960號之行政命令，採行「安全容許、牛豬分離、強制標示、排除內臟」之檢疫政策，在牛肉（含脂肪）的部分採行與國際標準相同之檢疫標準；惟在豬肉及內臟的部分，則為兼顧「國人特殊膳食習慣」及「相關產業發展」，仍維持既有「零檢出」的檢疫政策，全面禁止含萊克多巴胺的畜產品進口。針對此我國特殊之管制作法，本文將以國際經貿法的觀點，依據WTO協定中與檢疫措施最密切相關的SPS協定規範、過往案例之判決及相關文獻，分析我國進口檢疫規定之適法性，藉以思考目前畜產品進口的議題，並判斷該措施將來是否存在遭非難之可能，希冀能對於我國日後檢疫政策走向提供一實質性之參考及展望。 / Since 2005, the issue of liberalizing the import of meat containing Ractopamine had sparked great controversy in Taiwan, resulting from the lack of clear and definite scientific evidences worldwide to prove the harmlessness toward human body under JECFA’s maximal residue level and acceptable daily intake. Owing to the abusing of other much more poisonous Beta-adrenergic agonist (e.g., Clenbuterol, Salbutamol) by some of illegal stockbreeders causing the vibration of meat market and industry, Taiwan’s government had decided to ban the residual of Beta-adrenergic agonist including Ractopamine contained in both domestic and import meat products since 2006. After Codex Alimentarius Commission finally voted through the international standard of Ractopamine in 2012, Taiwan’s Legislative Yuan amended former regulations, approving the import of beef which conformed to Codex’s international standard, while still remained the prohibition of pork containing Ractopamine. This essay staying with the view of international trade law, in particular the Agreement on the Application of Sanitary and Phytosanitary Measures under World Trade Organization, tries to analyze the consistency of Taiwan’s meat regulations with the SPS agreement in order to prospect Taiwan’s trade policy and meat regulations regarding Ractopamine in the future.

Esta pesquisa teve como objetivo avaliar os efeitos da imunocastração e de diferentes beta-agonistas (BAA) sobre características de carcaça e rendimento dos cortes comerciais, de animais machos da raça Nelore, terminados em confinamento. Foram avaliados 96 bovinos, divididos em dois grupos, imunocastrados e não-castrados. Após 70 dias de confinamento, os animais foram divididos em três grupos e alimentados com uma das seguintes dietas: CON - dieta padrão, sem a adição de BAA; ZIL - dieta padrão acrescida Cloridrato de Zilpaterol (80 mg/animal/dia) e RAC - dieta padrão acrescida Cloridrato de Ractopamina (300 mg/animal/dia). Após 24 horas de resfriamento, foram obtidos o peso da carcaça fria (PCF) e rendimento de carcaça fria (RCF), além das perdas por refrigeração (PR). Em seguida foram obtidos os pesos e as percentagens do dianteiro, traseiro pistola e ponta de agulha de cada um dos cortes individuais e do total da porção comestível. Não houve interação entre a condição sexual e os tratamentos. Não houve efeito da condição sexual e de BAA sobre o PCF, PR e EGS, entretanto, animais do tratamento ZIL apresentaram maior RCF em comparação ao CON e RAC, que não diferiram entre si. Animais não castrados apresentaram maior peso dos cortes primários e dos cortes individuais. Com relação aos BAA, os maiores pesos e percentagens de cortes primários e individuais foram observados para o tratamento ZIL em comparação ao CON. O tratamento RAC apresentou valores intermediários em relação aos demais. Os BAA aumentam o peso e a percentagem dos cortes das carcaças em relação a animais sem BAA. / This research aimed to evaluate the effects of different immunocastration and beta-agonists on carcass traits of male Nellore, finished in feedlot. Evaluated 96 cattle and divided in two groups, non-castrated e immunocastrated. After 70 days of feedlot, the animals were divided into three groups and fed one of the following diets: STD - standard diet used, without addiction of BAA; ZIL - standard diet plus zilpaterol hydrochloride (80 mg/animal/day) e RAC - standard diet plus ractopamine hydrochloride (300 mg/animal/day). After 48 hours of cooling, the cold carcass weight (CCW) and cold dressing percentage (CDP) were obtained, in addition to cooling losses (CL) and subcutaneous fat thickness (SFT). Then the weights and percentages of the forequarter, hindquarter and side cut of each of the individual sections and the total edible portion were obtained. There was no interaction between sex condition and treatments. No effect of sex condition and BAA about the CCW, CL and SFT, however, the animals of ZIL treatment showed higher CDP compared to STD and RAC, which did not differ. Uncastrated animals showed greater weight of primal cuts and individual cuts. With respect to the BAA, the higher weight percentages of primary and individual sections were observed for treatment ZIL compared to CON. The RAC treatment showed intermediate values in relation to others. The BAA increases the weight and the proportion of the carcass cuts compared to animals without BAA.

Doctor of Philosophy / Department of Animal Sciences and Industry / Michael E. Dikeman / Sixty cull cows were utilized to investigate the effects of feeding a single or sequence of β-adrenergic agonists (β-AA) on performance, mRNA expression, carcass traits, economics, meat palatability, and ground beef color. Treatments included: 1) concentrate fed for 74 d (C); 2) concentrate fed for 49 d then supplemented with ractopamine-HCl for 25 d (RH); 3) concentrate fed for 51 d then supplemented with zilpaterol-HCl for 20 d (ZH); 4), concentrate fed for 26 d then supplemented with RH for 25 d followed by ZH for 20 d (RH + ZH). No differences existed among treatments for performance or carcass characteristics. However, cows supplemented with ZH (ZH and RH + ZH treatments) had increased LM areas (P = 0.18) compared to control and RH cows. Sequential feeding of RH followed by ZH had no influence on β2-adrenergic receptor (AR) mRNA expression. However, β2-AR mRNA was increased (P < 0.05) in the RH and ZH treatments when RH or ZH was supplemented during the last 20 to 25 d of feeding. Myosin heavy chain (MHC) Type IIa mRNA decreased (P < 0.05) from d 24 to 51 in all cows, while MHC-IIx increased (P < 0.05) in the ZH and RH + ZH treatments during ZH supplementation. No differences were observed in ground beef color shelf-life among treatments. Effects of β-AA supplementation on meat palatability varied among muscles. Infraspinatus steaks had improved (P < 0.05) WBSF values with β-AA supplementation. Psoas major steaks from the RH + ZH treatment were rated as more tender than steaks from all other treatments. Non-enhanced LM steaks from ZH supplemented cows had higher (P = 0.12) WBSF values along with decreased (P < 0.0001) percentages of degraded desmin compared to control and RH cows. Collagen solubility of the LM was increased with ZH supplementation compared to RH and control cows. Enhancement of steaks with 0.1 M calcium lactate improved LM tenderness of β-AA supplemented cows. Implanting and feeding cull cows for 74 d, regardless of β-AA supplementation, added value by transiting cows from a “cull” cow to “white” cow market.

Muitos fármacos, principalmente os agonistas B-adrenérgicos, vêm sendo utilizados na produção animal e, devido às novas formas de pecuária intensiva, sua utilização tem crescido exponencialmente. Dentre os agonistas B-adrenérgicos, a Ractopamina (RAC) é o mais utilizado como agente repartidor de nutrientes, pois promove ganho de peso, eficiência alimentar, deposição de tecido muscular e rendimento da carcaça de suínos, bovinos, ovinos e perus. Neste contexto, o desenvolvimento de métodos analíticos capazes de detectar e quantificar a RAC na matéria-prima, no produto acabado, em pré-formulações enriquecidas com nutrientes e minerais e na ração é de suma importância no controle de qualidade do produto acabado comercializado por indústrias veterinárias, visando maior segurança para os animais e para o consumidor de carnes. Desta forma, este projeto tem como objetivo desenvolver e validar métodos analíticos capazes de quantificar o fármaco nestas 4 etapas (matéria-prima, produto acabado Ractosuin®, pré-mistura com complexo vitamínico-mineral e na mistura destes componentes com a ração). No primeiro capítulo deste trabalho está descrito o método para quantificação da RAC na matéria- prima e no produto acabado Ractosuin®. Este método apresentou-se linear no intervalo de concentração de 160,00 a 240,00 ug mL-1 (r> 0,99). Os coeficientes de variação nos estudos de precisão intra e interensaios foram inferiores a 2,0% e a exatidão intra e interensaios variaram de 97 a 100%. No segundo capítulo, foi utilizada a extração líquido-líquido e acetato de etila como solvente extrator para a análise da RAC no complexo vitamínico-mineral. A curva analítica foi linear no intervalo de concentração de 90,00 a 210,00 ug mL-1 (r > 0,99). Os coeficientes de variação nos estudos de precisão intra e interensaios foram inferiores a 1,5%, a exatidão intra e interensaios variaram de 98 a 102% e a recuperação ficou em torno de 94%. O terceiro capítulo mostra o método desenvolvido e validado para análise da RAC na ração. A RAC foi extraída da matriz utilizando a extração líquido-líquido com acetato de etila. A curva analítica apresentou-se linear no intervalo de concentração de 6,50 a 14,40 ug mL-1 (r > 0,99), o limite de detecção (LD) foi de 2,00 ug mL-1 e o limite de quantificação (LQ) foi de 4,00 ug mL-1. Os coeficientes de variação nos estudos de precisão intra e interensaios foram inferiores a 5,0%, a exatidão intra e interensaios variaram de 90 a 98% e a recuperação foi de 84%. Desta forma, os métodos desenvolvidos e validados podem ser aplicados em análises de rotina de controle de qualidade de indústrias veterinárias para a quantificação da RAC na matéria-prima, no produto acabado Ractosuin®, no complexo vitamínico-mineral e na ração. / Several drugs, especially B-adrenergic agonists, have been used in animal production and due to new forms of intensive livestock their use has grown exponentially. Among the B-adrenergic agonists, ractopamine (RAC) is the most used as a nutrient repartitioning agent, it promotes weight gain, feed efficiency, deposition of muscle and carcass yield of pigs, cattle, sheep and turkeys. In this context, the development of analytical methods able to detect and quantify RAC in the raw material, feed additive, in pre-formulation (feed additive) enriched with nutrients and minerals and in the ration is very important in quality control of pharmaceutical formulation marketed by veterinary industries for greater security for animals and to consumers of meat. Thus, this project aims to develop and validate analytical methods able to quantify the drug in these 4 stages (raw material, feed additive Ractosuin®, pre-mixed with vitamin mineral complex and the mixture of these components with the ration). In the first chapter of this work is described the method for quantification of RAC in the raw material and feed additive Ractosuin®. This method showed linearity over the concentration range from 160.00 to 240.00 ug mL-1 (r > 0.99). The coefficients of variation in studies of intra-and interassay precision were less than 2,0% and intra and interassay accuracy ranged from 97 to 100%. In the second chapter, we used liquid-liquid extraction and ethyl acetate as solvent extractor for the analysis of RAC in complex vitamin-mineral. The calibration curve was linear over the concentration range from 90.00 to 210.00 ug mL-1 (r > 0.99). The coefficients of variation in studies of intra and interassay precision were less than 1.5%, intra and interassay precision varied from 98 to 102% and the recovery was around 94%. The third chapter shows the method developed and validated for analysis of RAC in the ration. The RAC was extracted from the matrix by liquid-liquid extraction with ethyl acetate. The analytical curve was linear over the concentration range 6.50 to 14.40 ug mL-1 (r > 0.99), the limit of detection (LD) was 2.00 ug mL-1 and limit of quantification (LQ) was 4.00 ug mL-1.The coefficients of variation in studies of intra and interassay precision were less than 5.0%, intra and interassay accuracy ranged from 90 to 98% and the recovery was 84%. Thus, the methods developed and validated can be applied in routine analysis for quality control of veterinary industries for the quantification of RAC in the raw material, feed additive Ractosuin®, vitamin mineral complex and in the ration.

Muitos fármacos, principalmente os agonistas B-adrenérgicos, vêm sendo utilizados na produção animal e, devido às novas formas de pecuária intensiva, sua utilização tem crescido exponencialmente. Dentre os agonistas B-adrenérgicos, a Ractopamina (RAC) é o mais utilizado como agente repartidor de nutrientes, pois promove ganho de peso, eficiência alimentar, deposição de tecido muscular e rendimento da carcaça de suínos, bovinos, ovinos e perus. Neste contexto, o desenvolvimento de métodos analíticos capazes de detectar e quantificar a RAC na matéria-prima, no produto acabado, em pré-formulações enriquecidas com nutrientes e minerais e na ração é de suma importância no controle de qualidade do produto acabado comercializado por indústrias veterinárias, visando maior segurança para os animais e para o consumidor de carnes. Desta forma, este projeto tem como objetivo desenvolver e validar métodos analíticos capazes de quantificar o fármaco nestas 4 etapas (matéria-prima, produto acabado Ractosuin®, pré-mistura com complexo vitamínico-mineral e na mistura destes componentes com a ração). No primeiro capítulo deste trabalho está descrito o método para quantificação da RAC na matéria- prima e no produto acabado Ractosuin®. Este método apresentou-se linear no intervalo de concentração de 160,00 a 240,00 ug mL-1 (r> 0,99). Os coeficientes de variação nos estudos de precisão intra e interensaios foram inferiores a 2,0% e a exatidão intra e interensaios variaram de 97 a 100%. No segundo capítulo, foi utilizada a extração líquido-líquido e acetato de etila como solvente extrator para a análise da RAC no complexo vitamínico-mineral. A curva analítica foi linear no intervalo de concentração de 90,00 a 210,00 ug mL-1 (r > 0,99). Os coeficientes de variação nos estudos de precisão intra e interensaios foram inferiores a 1,5%, a exatidão intra e interensaios variaram de 98 a 102% e a recuperação ficou em torno de 94%. O terceiro capítulo mostra o método desenvolvido e validado para análise da RAC na ração. A RAC foi extraída da matriz utilizando a extração líquido-líquido com acetato de etila. A curva analítica apresentou-se linear no intervalo de concentração de 6,50 a 14,40 ug mL-1 (r > 0,99), o limite de detecção (LD) foi de 2,00 ug mL-1 e o limite de quantificação (LQ) foi de 4,00 ug mL-1. Os coeficientes de variação nos estudos de precisão intra e interensaios foram inferiores a 5,0%, a exatidão intra e interensaios variaram de 90 a 98% e a recuperação foi de 84%. Desta forma, os métodos desenvolvidos e validados podem ser aplicados em análises de rotina de controle de qualidade de indústrias veterinárias para a quantificação da RAC na matéria-prima, no produto acabado Ractosuin®, no complexo vitamínico-mineral e na ração. / Several drugs, especially B-adrenergic agonists, have been used in animal production and due to new forms of intensive livestock their use has grown exponentially. Among the B-adrenergic agonists, ractopamine (RAC) is the most used as a nutrient repartitioning agent, it promotes weight gain, feed efficiency, deposition of muscle and carcass yield of pigs, cattle, sheep and turkeys. In this context, the development of analytical methods able to detect and quantify RAC in the raw material, feed additive, in pre-formulation (feed additive) enriched with nutrients and minerals and in the ration is very important in quality control of pharmaceutical formulation marketed by veterinary industries for greater security for animals and to consumers of meat. Thus, this project aims to develop and validate analytical methods able to quantify the drug in these 4 stages (raw material, feed additive Ractosuin®, pre-mixed with vitamin mineral complex and the mixture of these components with the ration). In the first chapter of this work is described the method for quantification of RAC in the raw material and feed additive Ractosuin®. This method showed linearity over the concentration range from 160.00 to 240.00 ug mL-1 (r > 0.99). The coefficients of variation in studies of intra-and interassay precision were less than 2,0% and intra and interassay accuracy ranged from 97 to 100%. In the second chapter, we used liquid-liquid extraction and ethyl acetate as solvent extractor for the analysis of RAC in complex vitamin-mineral. The calibration curve was linear over the concentration range from 90.00 to 210.00 ug mL-1 (r > 0.99). The coefficients of variation in studies of intra and interassay precision were less than 1.5%, intra and interassay precision varied from 98 to 102% and the recovery was around 94%. The third chapter shows the method developed and validated for analysis of RAC in the ration. The RAC was extracted from the matrix by liquid-liquid extraction with ethyl acetate. The analytical curve was linear over the concentration range 6.50 to 14.40 ug mL-1 (r > 0.99), the limit of detection (LD) was 2.00 ug mL-1 and limit of quantification (LQ) was 4.00 ug mL-1.The coefficients of variation in studies of intra and interassay precision were less than 5.0%, intra and interassay accuracy ranged from 90 to 98% and the recovery was 84%. Thus, the methods developed and validated can be applied in routine analysis for quality control of veterinary industries for the quantification of RAC in the raw material, feed additive Ractosuin®, vitamin mineral complex and in the ration.

Made available in DSpace on 2015-03-26T13:55:25Z (GMT). No. of bitstreams: 1 texto completo.pdf: 778375 bytes, checksum: 97156e3e6f5b7ceee5985d54b84d365c (MD5) Previous issue date: 2014-07-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / To evaluate the effect of chromium yeast (CY) and ractopamine (RAC) on performance, carcass characteristics, meat quality, and blood, an experiment was conducted with 96 commercial castrated crossbred pigs with an average initial body weight of 75.07 ± 3.9 kg. Animals were distributed in a randomized-block experimental design with six treatments, eight blocks and two animals per stall. The treatments consisted of feeding plans (FP) in two phases: from 0 to 14 days; and from 14 to 42 days of age, respectively, composed of diets: Control/Control (CD/CD); Chromium yeast/Amino acids (CY/AA); Chromium yeast/Amino acids + Ractopamine (CY/AA+RAC); Control /Chromium yeast (CD/CY); Control/Amino acids + Chromium Yeast (CD/AA+CY); and Chromium Yeast/Amino Acids + Ractopamine + Chromium Yeast (CY/AA+RAC/CY). The greatest final weight and daily weight gain (P<0.0001) were observed in the animals subjected to CY/AA+RAC+CY. Feeding plan CY/AA+RAC provided an intermediate final weight and daily weight gain, similar to those obtained with the use of CY/AA+RAC+CY, CD/CD, CY/AA and CD/CY, but greater than CD/AA+CY. The pigs fed CY/AA+RAC+CY showed a greater fasted body weight (FW) (P<0.0001) as compared with CD/CD, CY/AA, CD/CY and CD/AA+CY. Feeding plan CY/AA+RAC provided an intermediate FW, similar to that obtained with the use of CY/AA+RAC+CY, CD/CD, CY/AA, but greater than CD/AA+CY. The evaluated FP did not influence (P>0.05) daily feed intake. The best feed-conversion results (P<0.0001) were obtained with CY/AA+RAC+CY and CY/AA+RAC. A larger loin-eye area was found in pigs subjected to CY/AA+RAC as compared with the use of CD/CY. The greatest muscle fiber diameter (P<0.011) was found in the pigs subjected to CY/AA+RAC+CY and CD/CY, which were higher than the group fed CD/CD. The liquid loss due to thawing determined in the meat of the pigs subjected to CD/CD was lower (P<0.009) than that observed with the use of CY/AA+RAC. A higher value of Cie a* was determined in the meat of the animals subjected to CY/AA+RAC as compared with CY/AA+ RAC+ CY. The pigs fed CY/AA+ RAC+ CY had a brighter meat than the other animals. The lowest TBARS concentration (P<.001) was observed in the meat of pigs subjected to CY/AA+RAC in relation to the group that consumed CY/AA. A greater concentration of myristic fatty acid (FA) (14:0) was found in the groups that received CY/AA+RAC as compared with the group fed CY/AA+RAC+CY. The pigs that received the FP with CY/AA+RAC+CY and CD/CY displayed greater levels of linoleic FA (18:2n6) in the longissimus dorsi muscle, as compared with the pigs fed CY/AA. The feeding plans did not affect the evaluated blood parameters (P>0.05). The use of chromium yeast and ractopamine or alone promoted positive alterations in the development of muscle cells in the pigs and in the meat quality, which should be considered when this mineral is used. The association of chromium yeast with ractopamine revealed improvements in the animal performance. / Para avaliar o efeito do cromo levedura (CrL) e ractopamina (RAC) em rações sobre o desempenho, características da carcaça, qualidade de carne e variáveis sanguíneas, foi realizado um experimento com 96 suínos machos castrados híbridos comerciais com peso corporal médio inicial de 75,07 ± 3,9 kg, distribuídos em delineamento experimental em blocos casualizados, com seis tratamentos, oito blocos e dois animais por baia. Os tratamentos foram constituídos de planos nutricionais (PN) em dois períodos consecutivos: período 1 de 0 a 14 dias e o período 2 de 14 a 42 dias, respectivamente, compostos pelas rações: Controle/Ração Controle (RC/RC); Cromo levedura/Aminoácidos (CrL/AA); Cromo Levedura/Aminoácidos + Ractopamina (CrL/AA+RAC); Controle/Cromo Levedura (RC/CrL); Ração Controle/Aminoácidos + Cromo Levedura (RC/AA+CrL) e Cromo Levedura/Aminoácidos+Ractopamina+Cromo Levedura (CrL/AA+RAC+CrL). Maior peso final (PF) e ganho de peso diário (GPD) (P<0,001) foi observado para os suínos submetidos ao PN CrL/AA+RAC+CrL. O PN CrL/AA+RAC proporcionou PF e GPD intermediário, semelhante aos obtidos com o uso de CrL/AA+RAC+CrL, RC/RC, CrL/AA e RC/CrL e superior ao PN RC/AA+CrL. Os suínos alimentados com o PN CrL/AA+RAC+CrL apresentaram maior peso de jejum (PJ) (P<0,0001) quando comparados aos PN RC/RC, CrL/AA, RC/CrL e RC/AA+CrL. O PN CrL/AA+RAC promoveu PJ intermediário, semelhante ao obtido com o uso de CrL/AA+RAC+CrL, RC/RC, CrL/AA e superior ao RC/AA+CrL. Os PN avaliados não influenciaram (P > 0,05) o consumo diário de ração. Os melhores resultados de conversão alimentar (P<0,001) foram obtidos com os PN CrL/AA+RAC+CrL e CrL/AA+RAC. Maior área de olho de lombo foi determinada nos suínos submetidos ao PN CrL/AA+RAC quando comparado a utilização de RC/CrL. Maior diâmetro da fibra muscular (P<0,011) foi verificado nos suínos submetidos aos PN CrL/AA+RAC+CrL e RC/CrL sendo estes superiores ao grupo consumindo RC/RC. A perda líquida por descongelamento determinada na carne dos suínos submetidos ao PN RC/RC foi inferior (P<0,009) a obtida com o uso do PN CrL/AA+RAC. Maior valor Cie a* foi determinado na carne dos animais submetidos ao PN CrL/AA+RAC quando comparado ao PN CrL/AA+ RAC+ CrL. Os suínos submetidos ao PN CrL/AA+ RAC+ CrL apresentaram maior tonalidade na carne frente aos demais animais. Menor concentração de TBARS (P<0,001) foi verificada na carne dos suínos submetidos ao PN CrL/AA+RAC frente ao grupo consumindo ração CrL/AA. Maior teor de ácido graxo (AG) mirístico (14:0) foi verificado para os suínos submetidos ao PN CrL/AA+RAC quando comparado ao grupo CrL/AA+RAC+CrL. Os suínos que receberam os PN com CrL/AA+RAC+CrL e RC/CrL apresentaram maior concentração de AG linolêico (18:2n6) no músculo Longissimus dorsi, frente aos suínos do PN CrL/AA. Os PN não influenciaram as variáveis sanguíneas avaliadas (P>0,05). O uso de cromo levedura e ractopamina promoveram alterações positivas sobre o desenvolvimento de células musculares nos suínos e na qualidade da carne que devem ser consideradas quando da utilização do mineral e o uso em associação a ractopamina revelou melhorias sobre o desempenho dos animais.