Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-11-18T12:55:36Z No. of bitstreams: 2 gustavo_henrique_campos_souza.pdf: 742717 bytes, checksum: ef326795d986831c7d96eea8901db2ce (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-11-18T12:56:03Z (GMT) No. of bitstreams: 2 gustavo_henrique_campos_souza.pdf: 742717 bytes, checksum: ef326795d986831c7d96eea8901db2ce (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2015-11-18T12:56:03Z (GMT). No. of bitstreams: 2 gustavo_henrique_campos_souza.pdf: 742717 bytes, checksum: ef326795d986831c7d96eea8901db2ce (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2011 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O presente trabalho foi realizado em Couto de Magalh?es de Minas- MG no m?s de Maio, com o objetivo de avaliar diferentes n?veis de inclus?o de ractopamina na dieta para su?nos em termina??o. Foram utilizados 32 su?nos h?bridos comerciais com o peso inicial de 88,0 ? 4,0 kg e peso final de 109,0 ? 5,0 kg. Os animais foram distribu?dos em delineamento inteiramente casualizado, composto por quatro tratamentos (4, 8, 12 e 16 ppm de ractopamina) e quatro repeti??es. A unidade experimental constitu?da por dois animais, um macho e uma f?mea na baia, sendo que nas dietas experimentais houve um aumento de 30% de lisina digest?vel. As an?lises estat?sticas das vari?veis de desempenho (consumo de ra??o, ganho de peso e convers?o alimentar), das caracter?sticas quantitativas de carca?a (profundidade de lombo, espessura de toucinho, porcentagem de carne magra e deposi??o de carne magra di?ria) e dos par?metros fisiol?gicos (temperatura de superf?cie, frequ?ncia respirat?ria e temperatura retal) foram determinadas por an?lises de regress?o. O per?odo experimental teve dura??o de 14 dias. A temperatura m?dia do ar obtida foi de 23,7 ? 0,5?C, a umidade relativa foi de 69,6 ? 5,2% e o ?ndice de Temperatura de Globo e Umidade (ITGU) foi calculado em 71,1 ? 1,3. Os n?veis de ractopamina n?o influenciaram o ganho de peso, entretanto, foi observado efeito quadr?tico sobre o consumo de ra??o e a convers?o alimentar dos su?nos, de acordo com o aumento do n?vel de ractopamina na dieta, que melhorou at? o n?vel estimado de 11 e 13,2 ppm respectivamente. Os n?veis de ractopamina n?o influenciaram a espessura de toucinho, profundidade de lombo e porcentagem de carne magra, medidas por ultra-som. Observou-se efeito quadr?tico na deposi??o de carne magra di?ria dos su?nos com o aumento do n?vel de ractopamina na dieta, que melhorou at? o n?vel estimado de 11,4 ppm. Os n?veis de ractopamina n?o influenciaram a frequ?ncia respirat?ria dos su?nos. Notou-se que os n?veis crescentes de ractopamina nas dietas, promoveram aumento linear na temperatura retal e temperatura superficial. Concluiu-se que a suplementa??o de 13,2 e 11,4 ppm de ractopamina em dietas para su?nos em termina??o, durante 14 dias pr?-abate, proporcionam melhores resultados de convers?o alimentar e deposi??o de carne magra di?ria. No entanto, com o aumento dos n?veis de ractopamina, foi observada moderadas altera??es fisiol?gicas, n?o afetando o desempenho dos animais. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, [2011]. / ABSTRACT This work was performed in Couto de Magalh?es de Minas Gerais in the month of May, with the objective of evaluate different levels of inclusion of ractopamine in diet for finishing pigs. We used 32 commercial hybrid pigs with initial body weight of 88.0 ? 4.0 kg and final weight de109 ? 5.0 kg. The animals distributed in a completely randomized design, with four treatments (4, 8, 12 and 16 ppm ractopamine) and four replications. The experimental unit consists of two animals, one male and one female in the bay, and the experimental diets was an increase of 30% of lysine digestible. The statistical analysis of the performance variables (feed intake, weight gain and feed conversion), quantitative characteristics of the carcass (loin depth, backfat thickness, lean percentage and lean meat gain per day) and the physiological parameters (surface temperature, respiratory rate and rectal temperature) were determined by regression analysis. The experimental period lasted 14 days. The average temperature recorded was 23,7 ? 0,5?C, relative humidity was 69,6 ? 5,2% and BGHI was calculated at 71,1 ? 1,3. The levels of ractopamine did not affect weight gain, however, was observed quadratic effect on feed intake and feed conversion of pigs, according to the increased level of ractopamine in diet, which improved up to the level of 11 and 13,2 ppm respectively. The levels of ractopamine did not affect backfat thickness, loin depth and lean percentage, measured by ultrasound. There was a quadratic effect on daily lean meat gain of pigs with increased levels of ractopamine in the diet, which increased up to the estimated level of 11.4 ppm. The levels of ractopamine did not affect the respiratory rate of pigs. It was observed that increasing levels of ractopamine in diets, a linear increase in rectal temperature and surface temperature. We conclude that the supplementation of 13.2 and 11.4 ppm of ractopamine in diets for finishing pigs during 14 days pre-slaughter, showed the best feed conversion and daily lean meat gain. However, with increasing levels of ractopamine, there is moderate physiological alterations, not affecting the performance of animals.