Felipe Queiroga Cartaxo

Correlações entre as características obtidas in vivo por ultra-som e as obtidas na carcaça de cordeiros terminados em confinamento

The objective this study was to evaluate the correlation between traits obtained real time ultrasound and those obtained in the carcass of feedlot finished lambs. Forty eight no castrated, woolless crossbred Santa Ines lambs with initial 20.0 kg LW and 103 days old. The measures obtained by ultrasound in real time were determined using by Aloka 500SSD ultrasound machine, equipped with 3.5-MHz linear transducer. Before the slaughter, using the real time ultrasound, were measured between at 12th - 13th ribs of the lambs the subcutaneous fat thickness (USFT) and longissimus muscle area (ULMA), slaughter body weight (SBW) and the corporal condition (CC). After the slaughter were obtained the hot carcass weight (HCW), internal fat percentage (IFP), hot carcass dressing (HCD), carcass subcutaneous fat thickness (CSFT) and the longissimus muscle area (CLMA). There was correlation between traits measured by real time ultrasound and those obtained in the carcass, except for SBW vs CSFT (0.22) and HCW vs CSFT (0.33). Highly correlation was observed between longissimus muscle area obtained by real time ultrasound and the same measure determined in the carcass. The measures of USFT and CSFT showed also significant correlation. The use of the ultrasound was an efficient method to estimate, in real time, the loin eye area and fat thickness of the lambs.

Características quantitativas da carcaça de cordeiros terminados em confinamento e abatidos em diferentes condições corporais

The objective of this study was to evaluate the effects of the genotypes and body condition on the carcass dressing of lambs finished in feedlot. Twenty-four Santa Ines and 24 ½ Dorper × ½ Santa Ines crossbred lambs averaging 19.8 kg of weight and 103 days old were used in the trial. The adaptation period to the facilities and diet was of 14 days. The animals received complete ration with 30% of manicoba hay (Manihot pseudoglaziovii) and 70% of concentrate. The experimental design consisted of a completely randomized 2 × 3 factorial design (two genotypes and three corporal conditions) with different number of replicates. No differences between genotypes for the quantitative carcass traits studied were observed, except for the percentage of internal fat, fat thickness in the fat condition and dressing of the leg and rib in the intermediate corporal condition. The effect of the body condition within the genotype increases the internal fat percentage, fat thickness, compactness index of the carcass and weights of the saleable cuts, except for the weight of the neck in Dorper × Santa Ines crossbred lambs.

Morphometric and carcass characteristics of kid goats and lambs finished in feedlots

The objective of this study was to evaluate the genotype effect on the morphometric and quantitative characteristics of carcasses of kids and lambs finished in feedlot. A total of 34 entire male animals was used, 12 kid goats (½ Boer ´ ½ SRD), 12 kid goats (½ Anglo Nubiano ´ ½ SRD) and 10 Santa Ines sheep, with initial live weight of 18.3 kg, average age of 135 days at the beginning of the trial. The averages of withers height, corporal compactness and thoracic perimeter of the Santa Ines genotype were superior to those of the kid genotypes. The hot and cold carcass dressing of the genotypes was similar, but losses from cooling in the Anglo Nubiano crossbred kid goats and Santa Ines lambs were larger than in the Boer crossbreds. Significant differences were observed among the genotypes only for carcass compactness. The lambs deposited more covering fat, presented larger loin eye area and leg circumference than the kid goats.

Características de carcaça determinadas por ultrassonografia em tempo real e pós-abate de cordeiros terminados em confinamento com diferentes níveis de energia na dieta¹

Objetivou-se avaliar as caracteristicas de carcaca por ultrassonografia em tempo real e apos o abate e a relacao entre essas caracteristicas e os rendimentos de carcaca de cordeiros de diferentes genotipos terminados em confinamento com diversos niveis de energia na dieta. Foram utilizados 54 cordeiros nao-castrados - 18 Santa Ines puros (SI), 18 ½Dorper x ½Santa Ines (Dp x SI) e 18 ½Santa Ines x ½Sem Raca Definida (SI x SRD) - com media de 150 dias de idade e peso medio de 22,60 kg no inicio do experimento. As dietas continham 17% de proteina bruta e 2,40 Mcal/kg MS e 2,90 Mcal/kg MS. As mensuracoes realizadas por ultrassonografia e diretamente na carcaca dos cordeiros apresentaram resultados similares. Os cordeiros alimentados com a dieta contendo 2,90 Mcal/kg apresentaram maior area de olho-de-lombo, melhor conformacao e acabamento de carcaca e maior quantidade de gordura pelvico-renal. Os cordeiros Dp x SI apresentaram maior area de olho-de-lombo e musculosidade por 100 kg de PV em comparacao aos SI x SRD e foram superiores a todos os genotipos quanto a espessura de gordura subcutânea, a conformacao e ao acabamento de carcaca. O marmoreio observado nos cordeiros Dp x SI foi superior aos dos Santa Ines. As correlacoes das medidas tomadas por ultrassonografia e na carcaca foram altas e significativas, exceto o marmoreio. Houve correlacao significativa entre conformacao da carcaca e acabamento, marmoreio, espessura de gordura subcutânea e gordura pelvico-renal. As gorduras de cobertura avaliadas subjetivamente e objetivamente apresentaram correlacoes altas e significativas. A dieta e o genotipo influenciam as caracteristicas de carcaca de cordeiros.

Efeitos do genótipo e da condição corporal sobre o desempenho de cordeiros terminados em confinamento

The objective of this study was to evaluate the performance and the gross margin of profit of lambs finished in feedlot. Thirty-two no castrate male lambs from the genotype Santa Ines and crossbred Dorper × Santa Ines and two body condition, intermediate and fat, were used. The lambs were 16 Santa Ines (SI) and 16 ½ Dorper × ½ Santa Ines (DpSI), with average 103 days old and 20.0 kg BW. The lambs were full fed ration with 30% of manicoba hay (Manihot pseudoglaziovii) and 70% of concentrate. The adaptation period to the installation and the diet was of 14 days. A completely randomized design in a 2 × 2 factorial arrangement (genotype and body conditions score) was used. There was no significant effect of genotypes on any performance characteristic, however, the crossbred (DpSI) obtained greater margin of profit. The body condition affected the dry matter intake, feed conversion and the number of days in feedlot. The lambs with intermediate body condition consumed 1.04 kg/day and 82.64 g/kg 0.75, while those with fat body condition consumed 1.15 kg/day and 86.79 g/kg0.75. The lambs with intermediate body condition showed lower dry matter intake and better feed conversion, which resulted in fewer days in feedlot and greater gross margin of profit compared to lambs with fat body condition, independently of the genotype.

Qualidade física e sensorial da carne de cordeiros de três genótipos alimentados com rações formuladas com duas relações volumoso: concentrado

The objective of this work was to evaluate sensory atributes (tenderness, odor, flavor, juiciness and color) and physical attributes (shearing force, cooking losses and the color parameters of L*, a*, b*) in addition to content of iron in the meat of Santa Ines (SI), Dorper × Santa Ines (DP × SI) and Without Definite Breed Pattern (WDB) lambs, finished in feedlots, in function of two roughage:concentrate (50:50 and 20:80) relationships in the diet. It was used 54 whole lambs (18 from each genotype, with initial average weight of 23 kg and at 150 days of age) slaughtered at 36 kg of live weight. The fed diets favored differentiation in meat color. Bright intensity (L*) differed among the genetic groups. In animals fed diet with high level of concentrate, the meat presented fewer cooking losses. It was observed the existence of a correlation between the intensity of red (a*) and the color of fresh meat and among dietary iron concentration in the meat and and bright intensity (L*). Meat of SI and SRD lambs is less tough and more juicy than meat of Dorper × Santa Ines. The ratio roughage:concentrate in the diet does not promote changes in sensory attributes and physical parameters of the meat.

Biological and economic performance of feedlot lambs feeding on diets with different energy densities

The objective of this study was to evaluate performance, carcass dressing and gross profit margin of lambs of different genotypes finished in feedlot with diets containing two levels of energy (2.40 Mcal/kg dry matter - DM or 2.90 Mcal/kg DM). Fifty-four non-castrated lambs of the following genotypes were used: Santa Ines, F1 Dorper × Santa Ines and F1 Santa Ines × undefined breed at approximately 150 d of age averaging 22.6 kg of live body weight. Lambs subjected to the diet containing 2.90 Mcal/kg DM stayed in feedlot for a shorter period of time. Moreover, they showed lower intake of dry matter and water in addition to greater daily weight gain and corporal score. There was interaction of feed conversion, carcass dressing yield and gross profit margin. The Dorper × Santa Ines lambs showed similar feed conversion in the two diets. However, Santa Ines lambs and Santa Ines × undefined breed lambs showed better feed conversion with the diet containing 2.90 Mcal/kg DM. The carcass dressings of the Santa Ines × undefined breed lambs were similar for both diets. Furthermore, the carcass dressing values were higher for the Santa Ines and Dorper × Santa Ines which received the diet with higher energy density. The gross profit margin is higher for Dorper × Santa Ines lambs in relation to genotype Santa Ines × undefined breed lambs when subjected to the diet with 2.40 Mcal/kg DM.

Effect of frame size on performance and carcass traits of Santa Inês lambs finished in a feedlot

The objective of this study was to evaluate the performance, qualitative, morphometric and quantitative carcass traits of Santa Ines lambs of different frame sizes finished in a feedlot. Twenty 120-day-old intact lambs with a 25.0±3.1 kg average body weight at the beginning of the experiment were used. Lambs received a diet containing 17% crude protein and 2.70 Mcal/kg dry matter. Frame size influenced performance and tissue composition in the carcasses of the lambs. Lambs with large frame sizes showed better carcass conformation compared with those of medium-sized frames. Frame size was found to have a significant effect on rump perimeter. Large-framed lambs showed higher compactness on the carcass index and carcass dressing area compared with medium-framed lambs. The cuts of large-framed lambs weighed more than those of mediumframed lambs. However, no significant differences were found in dressing.

Physicochemical characteristics and fatty acid profile of meat from lambs with different genotypes and diets

The objective of this study was to evaluate the chemical composition and fatty acid profile of meat from Santa Ines, Dorper × Santa Ines, and undefined-breed lambs finished in a feedlot system according to two forage:concentrate ratios (50:50 and 20:80) in the diet. Overall, 54 non-castrated animals were used (with an average initial weight of 23±1.5 kg at 150 days old) and were slaughtered when they reached 36 kg of live weight or 63 days of confinement. Diets with high concentrate levels favored meat production with higher protein content. Among the saturated fatty acids, only heptadecanoic (C17:0) and arachidic acids (C20:0) differed among the treatments. The amount of oleic acid detected in the meat ranged from 49.2 to 51.9 g/100 g, making this one the most representative fatty acids. Regardless of the diet and genotype, the unsaturated fatty acid and desirable fatty acid levels in the lamb meat characterize it as of satisfactory quality for the consumer market.

Características de carcaça de cabritos de diferentes genótipos terminados em confinamento

The objective of this study was to evaluate the quantitative and qualitative carcass traits in goat kids finished in feedlot. Thirty goat kids were used non-castrated, with 10 Anglo Nubian x Undefined Breed (UB), 10 Boer x UB and 10 Undefined Breed, with average 19.05 kg BW at the beginning of the experiment, divided into a completely randomized design. The diet used was unique and complete, containing 15.5% crude protein and 2.58Mcal kg-1 DM. The Anglo Nubian x UB goat kids showed higher carcass dressing, fat thickness and GR site in comparison to Boer x UB. However, the Boer x UB obtained higher muscularity index compared with Anglo Nubian x UB and UB. The UB goat kids showed lower percentage of fat and higher muscle:fat relation when compared with Boer x UB. No differences between genotypes for the weight and yields, except for the weight and yields of neck. The Boer x UB goat kids showed better conformation and carcass fatness compared to Anglo Nubian x UB and UB. There was significant correlation between conformation and carcass fatness. Correlation was observed between marbling, fat thickness and pelvic-renal fat. The fat thickness and GR site showed significant correlation, indicating that these evaluations represent the back fat in the carcass of kids goat. The genotype influenced the fat thickness, carcass dressing, conformation and carcass fatness.