Vitamina E na produção e características da carcaça e da carne de cabritos ½ Boer-Saanen

• Autor(a) principal: Possamai, Ana Paula Silva
• Data de Publicação: 2015
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Estadual de Maringá (RI-UEM)
• Texto Completo: http://repositorio.uem.br:8080/jspui/handle/1/1656
• topic: Caprinos; Carcaça; Lombo; Alometria; Alfa-tocoferol; Antioxidante; Brasil.; Alpha tocopheryl; Allometry; Antioxidant; Goat kids; Loin; Brazil.; Ciências Agrárias; Zootecnia

The goal of this study was to evaluate the performance, carcass quantitative characteristics, shelf life and physicochemical characteristics of Longissimus dorsi muscle and the allometric growth of cuts and tissue of goat kids ½ Boer-Saanen fed diets with different levels of vitamin E. Thirty-five goat kids ½ Boer-Saanen were used, with an average age of 122 ± 3.57 days and initial body weight of 21 ± 2.85 kg, distributed in a completely randomized design in four treatments, being the control without addition of vitamin E, and other treatments containing 50, 150 and 450 mg of dl-α-tocopheryl acetate/kg of DM. The animals were weighed at the beginning of the study and each 14 days to monitor the body weight and make diet adjustment. When the average body weight reached 32 kg, the animals were fasted for 16 hours and subsequently slaughtered to obtain the carcass. Quantitative carcass characteristics were evaluated, and samples of the Longissimus dorsi muscle were taken to the physicochemical evaluations and visual assessment of meat shelf life. The left half carcass was sectioned into five anatomical regions, as follows: neck, shoulder, ribs, loin and leg. To evaluate the allometric growth of the cuts and tissues, the cuts: shoulder, loin and leg were dissected and separated into following tissues groups: total fat, muscle and bone. There were no treatment effects on performance and carcass quantitative characteristics of the animals supplemented with vitamin E in diet, however there was effect of gender on performance and carcass characteristics of the animals, where males showed better results. To the physicochemical characteristics of Longissimus dorsi muscle, there were no effects of treatments in color, pH and muscle shear force. However, there was a positive linear effect for the moisture content and cooking loss, and negative linear effect on crude protein and total fat content in Longissimus dorsi muscle of the animals supplemented with vitamin E in diet. In the fatty acid concentration in Longissimus dorsi muscle, improvements were observed in the fatty acid profile, with quadratic effect for myristic, conjugated linoleic acid and arachidonic fatty acids, and for the sum of poly-unsaturated fatty acids and the ratio polyunsaturated fatty acid: saturated fatty acid, and a negative linear effect for the palmitoleic fatty acid. There was a reduction in lipid oxidation in the meat days of storage and increased incorporation of vitamin E in muscle of the animals that consumed diets supplemented with vitamin E. The shelf life of meat was influenced by vitamin supplementation in animal diet and showed greater survival time of meat in chemical evaluation by the method of thiobarbituric acid reactive substances and the visual evaluation method for consumers, wherein the chemical method was more accurate to assess the prediction of shelf life. There were diet effects on allometric growth of carcass commercial cuts of animals supplemented with vitamin E, and on the development of tissues (muscle, fat and bone) in the main commercial cuts of the goat kids' carcass. Vitamin E can be used to fed ½ Boer-Saanen goat kids in levels up to 150 mg, without affecting the productive performance of the animals, showing improvements in chemical composition of Longissimus dorsi, in the vitamin E incorporating in muscle tissue, reducing lipid oxidation, better consumer acceptance of meat supplemented and proper development of cuts and tissues cuts of animals carcasses.