Glicerina bruta na dieta de bovinos Nelore e F1 Red Angus x Nelore: desempenho, caracteristicas de carcaça e avaliação qualitativa de nove músculos, maturados ou não

• Autor(a) principal: Oliveira, Ivanna Moraes de
• Data de Publicação: 2013
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1833
• topic: Glicerina; Bovinos; Nelore; Glycerin; Cattle; Nellore; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::NUTRICAO E ALIMENTACAO ANIMAL

This thesis consists of three papers, evaluating the influence of genetic group (Nellore or Red Angus x Nellore) and crud glycerin (5% or 15% crude glycerin replacing corn, on total dry matter basis). In the first we evaluated intake, performance and carcass traits (writing the standard of Livestock Science); in the second we evaluated the influence of genetic group (Nellore or F1 Red Angus x Nellore) and crude glycerin in qualitative characteristics of muscle L. dorsi and in the third evaluated the influence of breed and crude glycerin in qualitative characteristics of nine muscles, not aged and aged for seven days (writing the standard of Meat Science). Crossbreds had higher intake (P=0.0339) and digestibility (P=0.1829) compared to the NE. The intake (P=0.1344) and digestibility (P=0.7239) of neutral detergent fiber were not affected by genetic group. Except for digestibility of EE, greater in animals fed with 15% GB, intake (P=0.0769) and digestibility (P=0.2973) were not affected by diet. NA animals had greater average daily gain (ADG; P=0.0012) and final body weight (FBW; P=0.0012). The ADG (P=0.0294) was higher in animals fed with 5GB% and there was a trend towards greater FBW (P=0.0654) in these animals. The cold carcass weight, carcass length and ribeye area was greater in the NA (P=0.0249), while subcutaneous fat thickness and cold carcass yield were not affected by genetic group (P=0.5292). The cold carcass yield was greater in animals fed with 15% GB (P=0.0450). The cuts yield did not differ between diets (P=0.2426) and between genetic groups (P=0.0754). The blood glucose concentration was higher in NE animals (P=0.0097) and was not influenced by diet (P=0.9573). Were not affected by group genetic (P=0.0908) and content of crude glycerin (P=0.0733): serum insulin, ultimate pH and temperature, frequency of muscle fibers and area type IIB fibers, objective measurements of color, Warner-Bratzler shear force, myofibrillar fragmentation index, thawing loss, dripping loss, evaporation loss, cooking loss, total loss, ether extract content, ash content and water content. The area of type I muscle fibers did not differ between genetic groups (P=0.0521) and was higher in animals fed with 15%GB (P=0.0733). The area of type IIA fibers was higher in L. dorsi of NA animals (P=0.0002) and animals fed with 15%GB (P=0.0068). The collagen solubility was higher in meat from NA animals (P<0.0001) and no diet effect for this variable was observed (P=0.1146). There was an interaction between genetic and diet on the amount of total collagen (P=0.0002) of meat. The protein content (GG P=0.2197; CG P=0.0468) was higher in meat from animals fed with 15%GB (P=0.0468) and was not influenced by genetic group (P=0.2197). For every muscle aging decreased WBSF, did not affect L* value, a* value and b* value increased. The aging did not affect MFI from muscles BFD and TFL, reduced the cooking loss in LD muscle and total loss in muscles LD, GM, SM and VL. The muscles BFD, PM and TFL had higher content of intramuscular fat. In general, regardless of genetic group, higher levels of CT were observed in muscle VL and lower in muscle PM; while higher CS was observed in the muscles GM, PM, LD and lower in the muscles BF, ST and VL. Similarly, the PM muscle showed higher frequency of type I fibers, the VL muscle higher frequency of fiber type IIA, while PM and BFD showed lower frequency of IIB fibers. Crossbred animals exhibit better performance than Nellore and crude glycerin replacing corn on total dry matter basis by 15% reduces weight gain. The inclusion of crude glycerin in the diet did not affect the quality of L. dorsi and meat can be produced with desirable quality characteristics from animals F1 Red Angus x Nellore and Nellore. The efficiency of aged is dependent muscles, improving the texture of Biceps Femoris (Dorsal), of Tensor Fascia latae, Semitendinosus and Semimembranosus. Muscles Psoas major, Gluteus Medius and Longissimus dorsi need not go through the aged, while for seven days, not improve sufficiently the texture of the Biceps femoris and Vastus lateralis. The total collagen content and collagen solubility seems to be the main determinant of differences in texture between different muscles. The crude glycerin seems to promote differential hypertrophy of muscle fibers in the Longissimus dorsi muscle.