Grãos de linhaça e período de confinamento na produção e características da carcaça e da carne de ovelhas

• Ano de defesa: 2013
• Autor(a) principal: Radis, Ana Cláudia
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual de Maringá; Brasil; Programa de Pós-Graduação em Zootecnia; UEM; Maringá, PR; Centro de Ciências Agrárias
• Palavras-chave em Português: Ovelhas; Ácidos graxos; Qualidade da carne; Características da carcaça; Suplementação lipídica; Período de terminação; Brasil.; Sheep; Fatty acids; Meat quality; Carcass characteristics; Lipid supplementation; Finishing period; Brazil.; Ciências Agrárias; Zootecnia
• Link de acesso: http://repositorio.uem.br:8080/jspui/handle/1/1566

The objective of this study was to determine the inclusion of flaxseed grain in diet and the necessary period of feedlot for culling ewes in the economic and carcass and meat characteristics. 88 disposal sheep were used, with initial body weight of 37.65 ± 6.98 kg, distributed by weight and body condition in twelve treatments. The treatments were the interaction between proportion of flaxseed (0, 5, 10 and 15%) and feedlot days (30, 45 and 60 days). There was a decrease in daily weight gain of sheep (0.340 to 0.100 kg / day) when increased the feedlot time and the inclusion level of flaxseed in diet. The sheep had the lowest performance on the combination of maximum inclusion of flaxseed in the first 30 days of feedlot, for weight gain and consumption, obtaining 2.92 kg and 1.14 kg, respectively. The inclusion of 15% flaxseed in the diet of sheep was high, which inhibited the animals' intake . The production cost for each kilogram of liveweight gain of sheep and the total cost of production increased gradually with the feedlot time and the inclusion level of flaxseed. Treatments that had higher net income was 5% inclusion of flaxseed and 45 days of confinement (R$ 1,640.42). The commercial carcass yeld increased with the sheep feedlot time, ranging from 43.44 to 49.17%. The average of carcass compactness index remained at levels appropriate for the performance (0.27 kg / cm). There was an increase in the loin percentage in relation to the feedlot days.. There was an increase to the J thickness and c thickness of Longissimus dorsi muscle according to the feedlot days, being the highest value 6.20 and 3.50 mm. It has been found that the inclusion of 15% flaxseed in diet of sheep may be considered excessive, since it was the treatment that had the lowest intake. The fraction of red meat (a *) increased with the proportion of flaxseed inclusion. There was an significant effect on the amounts of dry matter and total lipids of the muscle. There was an increase in intermuscle fat deposition. The shear strength (4.85 kgf/cm2) remained in the pattern expected (4.08 kgf/cm2) for this variable. Saturated fatty acids remained at low levels when the animals were fed with higher concentrations of flaxseed, highlighting the importance of introducing food with quality in animal feed. The fatty acid mono-unsaturated that was observed in higher amount was the oleic acid with 39.99%. For polyunsaturated fatty acids was observed an increase due to the presence of flaxseed grains in ration. In linolenic acid (C18: 3N3), where we observed higher levels at 45 days and increase of this according to the increased inclusion of flaxseed grains, demonstrating positive changes through diet. For the α-linolenic acid was observed quadratically increase in deposition, considering the feedlot time and flaxseed supplementation, achieving better results with addition of 10% of flaxseed grain in the total diet. The highest values of CLA obtained in this work are related to higher rates of inclusion of flaxseed in the diet of sheep, ranging from 1.15 to 5.72%). All groups of animals that received flaxseed had better rates of n6:n3, ranging between 1.81 and 4.14 for treatments with the addition of flaxseed. The inclusion of flaxseed grain in diet of sheep provided meat production with fatty acid profile within the recommendations of the World Health Organization.