Torta de girassol em suplementos para novilhas Nelore terminadas a pasto durante a estação seca

Abstract

This study was conducted for evaluate performance, carcass characteristics and meat quality of Nellore heifers supplemented with sunflower crushed replacing soybean meal at 0, 20, 40 and 60%. The supplements were provided in the amount of 0.8% of body weight (BW). The concentrates contents 28% CP, with 3.68, 5.65, 8.82 and 11.00% of ether extract (EE). Were used, 24 heifers approximately 24 months, maintained on Brachiaria humidicula during the dry season, and distributed in a completely randomized design. The heifers were weighed and monitored for body condition (BC) every 21 days. The experiment was conducted at Cerro Azul farm, in Itaporã-MS, between the months June-October of 2009, totaling 120 days of experimental period. Of the 24 heifers used in this study only 20 reached BC to slaughter (up 3.0), thus only 20 carcasses were evaluated in order to determine their qualitative and quantitative characteristics. The slaughter line, after complete bleeding, skinning and evisceration, were determine weighed liver, perirenal-pelvic fat, carcass length and of hot carcass weight (HCW). After 24 cooling were determined the cold carcass weight (CCW) and the left half part of carcass, between 12th and 13th ribs, were measured the fat thickness (FT) and loin eye area (LEA) in Longissimus muscle. In the right half carcass were evaluated commercial yield cuts of hindquarter. Alongside were collected from 800 g of strep loin, for evaluated the meat quality from animals such as shear force, pH, cooking loss, water holding capacity (WHC), color (Brightness - L *; intensity red color – a*, and intensity yellow color - b *), dry matter (DM), CP, EE and mineral matter (MM) of meat. Also sensory evaluation was performed by analyzing the flavor, tenderness and juiciness. The BC of animals has improved with the replacement of soybean meal with sunflower crushed, where the animals supplemented with sunflower crushed had the higher final BC (4.0, 4.0 and 3.7) for the replacement levels of 20, 40 and 60%. The animals supplemented without sunflower crushed had a BC of 3.6. The inclusion of sunflower cake improved the average daily gain (P<0.10) (average of 0.35 kg/day), representing an increase of 45.8% compared to supplementation with corn and soybean meal. There was no difference (P>0.05) between levels of substitution for the variables studied: slaughter weight, hot carcass weight (HCW), cold carcass weight (CCW), cooling losses (kg and % ), carcass length, carcass yield, front and rear yield, yield grade, the Brazilian commercial cuts (CCB), full rump, back ribs, flat round, inside round and loin eye area100 kg carcass (LEA/100 kg), fat thickness, liver and perirenal-pelvic fat, with mean values of 378.50 kg, 197.05 kg, 193.33 kg, 3.71 kg, 1.92%, 52.03%, 1.2 m, 60.35 kg, 37.98 kg, 78.17%, 62.14%, 3.18 kg, 2.09 kg, 3.98 kg, 5.06 kg, 32.54%, 4.52 mm, 3.59 kg and 2.41 kg, respectively. In meat quality does not affect (P>0.05) for pH, water holding capacity (WHC), cooking losses, shear force, lightness (L *), redness (a *), and intensity yellowness (b *), with mean values of 5.59, 65.51%, 31.93%, 7.69 kgf, 37.48, 18.42, 10.01, among the replacement levels tested. The chemical composition of Longissimus also had no effect (P>0.05) for moisture, CP, EE and MM. The sensory evaluation for flavor, tenderness and juiciness, showed an average of 6.22, 5.73 and 5.66. The substitution of soybean meal by sunflower crushed improved the daily gain and body condition of heifers finished on pastures during the dry season, without changing the characteristics of carcass and meat quality.