Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2004. / Härtill 6 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2004. / Härtill 5 uppsatser.

Thesis (MSc (Consumer Science)--Stellenbosch University, 2008. / The purpose of this study was to investigate the chemical composition mineral and cholesterol content of the different cuts (breast, drumstick and thigh) of raw guinea fowl meat. The study also aimed at establishing the effect of cooking method on guinea fowl quality attributes by investigating the effect of different cooking methods on the chemical composition and sensory attributes of the different cuts. The effect of injecting a brine solution on the chemical composition and sensory attributes were also investigated. There were no differences in terms of moisture content of the various cuts raw guinea fowl meat The breast had significantly higher protein content when compared to drumstick and thigh (P<0.05). The fat content was similar for all the cuts (P>0.05). Whilst the drumstick had significantly the lowest value for ash content when compared to the thigh. Saturated fatty acids (SFAs) and total unsaturated fatty acids (TUFAs) were not different (P>0.05) in all the cuts. Drumstick had significantly higher monounsaturated fatty acids compared to other cuts (P<0.05), and it had the highest polyunsaturated fatty acids (P<0.05). The breast had the lowest (P<0.05) n-6 fatty acid value (44.25) and had relatively the lowest Polyunsaturated:Saturated (P:S) fatty acid ratio of 1.74 when compared to the other cuts. High n-6:n-3 ratios, ranging from 7.05 to 16.58, were also found in all the cuts. Cholesterol was lowest (P<0.05) in the breast. Seventeen amino acids were found, including the eight of the nine essential amino acids. Significant differences were found in amino acid values for the different cuts. Values of iron were significantly higher in the drumstick and thigh cuts (P<0.05), whilst drumstick had the highest zinc content of all the cuts (P<0.05). On investigating the effect of three cooking methods (baking-bag, foil-wrap, open-roasting at 140ºC for 65 minutes) on the chemical composition, the open-roasting method produced higher moisture content (P<0.05) consistently for all cuts, with the breast having the highest and the drumstick the lowest (P<0.05). The moisture content of the baking-bag method on the other hand was consistently the lowest (P>0.05). This effect was significant for the breast, which had lost the most moisture (P<0.05). The baking-bag method consistently resulted in a higher protein content, which is attributed to the higher moisture loss (P<0.05) in comparison with the other methods, resulting in a more concentrated product. With regard to the fat content no effect resulting from the cooking methods could be observed (P>0.05), but the cuts’ natural fat content was reflected especially in the open–roasting method (P<0.05) giving further support to the understanding that the open-roasting method indeed made the least inroads on the chemical composition of guinea fowl meat under these restraints: controlled for cooking time and temperature, internal temperature not controlled. All the cuts cooked according to all the methods, had the favourable >0.4 Polyunsaturated:Saturated fatty acids (P:S) ratio, ranging from 0.91 to 1.42 between cuts and treatments. The n-6:n-3 ratio was below the recommended beneficial value, namely <4:1, in all the cuts irrespective of all the cooking methods, ranging from 2.47 to 3.08. The study of the effect of the three cooking methods (baking-bag, foil-wrap and open-roast) on the sensory attributes of the breast meat revealed that aroma-intensity of the three cooking treatments did not differ significantly (P>0.05). Foil-wrap produced a more tender and juicier product (P<0.05), while, when using the baking-bag method, values for flavour decreased (P<0.05). It is proposed that a higher internal temperature (which was not controlled) was attained when using the baking-bag method (temperature and time controlled) resulting in loss of volatile flavour components. The effect of the three cooking methods (baking-bag, foil-wrap and open-roast) on the proximate composition (moisture, protein, fat and ash) of raw and cooked breast meat was investigated. As anticipated raw breast meat had higher moisture content (74.55%, P<0.05) than the cooked cuts, with open-roasting showing the highest (68.55%) value and foil-wrap close second (68.12%). These values differed significantly from the baking-bag method (66.06%, P<0.05). An investigation on the effect of brine infusion on the sensory attributes and chemical composition (proximate and fatty acid composition, and mineral content) of breast meat, baked in foil-wrap, was carried out using descriptive sensory analysis with the injected breast and the control as variable. There were no significant differences (P>0.05) between the injected and the control samples for any of the sensory attributes of aroma, tenderness, initial juiciness, sustained juiciness and flavour. Judge:treatment variations were observed for all the attributes, and samples differed for all attributes except for aroma. It is proposed that the use of the hand injector could not effectively distribute the brine solution, hence the recommendation to repeat the experiment using an electronic multineedle-injector. No effect was observed for the proximate composition (P>0.05). Further research pertaining to cooking methods of meat of free-range guinea fowl is recommended to address certain issues that have been highlighted.

Thesis (MSc Food Sc (Food Science))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Fresh ostrich meat competes in well regulated and competitive international markets; therefore food quality and safety are of the utmost importance. At the same time the production process must be well controlled to be cost effective. Losses in meat yield through bruising and the trimming thereof as well as a high initial microbial load that causes a decrease in shelf-life is thus undesirable. The main objectives of this study were firstly to investigate the expected prevalent microbial growth on ostrich meat as well as possible environmental contaminants to establish which bears the greatest risk. Secondly to establish the best practice of removing bruised areas from carcasses from both a microbiological and meat yield perspective. Lastly to investigate bruises on carcasses to predict the possible causes thereof so as to minimize bruising during transport and handling. From this study it was concluded that the prevalent growth on carcasses was predominantly Grampositive which increased ten fold from post-evisceration to post-chilling, this was also associated with a marked increase in Gram-negative organisms. The most dangerous vector for contamination was found to be standing water containing Gram-negative human pathogens including Shigella, Salmonella and E. coli. Bruises to the necks (52.58% of all bruises) were the most frequent, the high side railings on transport trucks the probable cause thereof. It was indicated that aerobic viable counts decreased after cold trimming, where the opposite occurred on warm trimmed surfaces, while the average loss in meat yield per bird due to bruising was smaller for cold trimming. / AFRIKAANSE OPSOMMING: Vars volstruisvleis kompeteer in goed gereguleerde en kompeterende internasionale markte; dus is voedselkwaliteit en –veiligheid baie belangrik. Terselfdertyd moet die produksieproses goed beheer word en koste effektief wees. Verliese aan vleisopbrengs as gevolg van kneusings en die verwydering daarvan, sowel as ‘n hoë inisiële mikro-organisme lading wat ‘n verkorte rakleeftyd tot gevolg het, is dus ongewens. Die hoofdoelwitte van die studie was eerstens om die verwagte mikro-organisme groei op volstruisvleis en op moontlike omgewings kontaminasie bronne te ondersoek om vas te stel watter bronne die grootste risiko dra vir besmetting. Tweedens om die beste praktyd vir die verwydering van kneusings van die volstruiskarkasse te bepaal uit beide ‘n mikrobiologiese en vleisopbrengs oogpunt. Laastens om die omvang en verspreiding van karkaskneusings te ondersoek om die oorsaak daarvan te probeer aandui en sodoende kneusings tydens vervoer en hantering te verminder. Uit die studie was die volgende duidelik; die mikrobiese groei op karkasses was hoofsaaklik Gram-positief, tellings het tienvoudig toegeneem vanaf ontweiding tot na verkoeling, met ‘n gepaardgaande merkbare toename in Gram-negatiewe organismes. Die gevaarlikste oorsaak van omgewingskontaminasie was staande water wat Gram-negatiewe menslike patogene (insluitend; Shigella, Salmonella en E. coli) bevat het. Nekkneusings (52.58% van all kneusings) was die algemeenste; met die hoogte van die kantreëlings van die volstruistrokke die moontlike oorsaak daarvan. Dit is bewys dat die aerobe mesofiele plaattelings afgeneem het na koue verwydering, maar dat die teenoorgestelde gesien is op warm gesnyde areas; die gemiddelde verlies in vleisopbrengs per volstruis as gevolg van kneusingverwydering is kleiner tydens koue verwydering.

Thesis (MSc Food Sc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Please refer to fulltext for abstract. / AFRIKAANSE OPSOMMING: Sien asb volteks vir opsomming

Thesis (MSc Food Sc (Food Science))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The aim of this study was to investigate the impact of an extensive (free-range) and intensive (feedlot) production system on the consumer’s intrinsic preference cues (physical attributes, chemical composition, fatty acid profile, aroma, flavour, initial juiciness, sustained juiciness, first bite, residue, instrumental tenderness) for three muscles (Biceps femoris, Longissimus dorsi, Semimembranosus) of Dohne Merino lambs (8 months). Secondly to investigate the effect of natural exercise (grazing, extensive production systems) or restrictive movement (intensive production systems), on the muscle fiber type composition of the same lamb muscles and the subsequent effect on the meat quality characteristics. Intensively raised lambs produced carcasses with a significantly higher dressing percentage, thicker subcutaneous fat layer (13th rib and 3rd/4th lumbar vertebra) and a greater fat ratio (carcass composition). Meat of intensively raised lambs had a higher (p < 0.050) Homo-glinolenic (C20:3n6), Eicosapentaenoic (C20:5n3), Docosapentaenoic acid (C22:5n3) content and n3:n6 ratio. Extensively reared lambs had a higher (p < 0.050) slaughter weight, cold carcass weight and the meat of these lambs had a higher myoglobin content. Results of this study indicate that intensively reared lambs produced meat with more favourable sensory characteristics compared to the extensive production system as well as a significant increase in sensory tenderness for Biceps femoris muscle. Overall the Biceps femoris muscle was the muscle that was primarily affected by the treatment (production systems). The Biceps femoris from intensively raised lambs contained significantly more intramuscular fat and type IIB muscle fibers whereas the Bicpes femoris of the lambs from the extensive production system contained more (p < 0.050) insoluble collagen and type I muscle fibers. During texture profile analysis (instrumental tenderness test) the Longissimus dorsi and Semimembranosus of extensively raised lambs required a higher (p < 0.050) compression force during the first cycle of compression, indicating that these muscles are tougher. The results of this study provided valuable insight into the impact of production systems on lamb meat quality and that the application of intensive production systems will increase the sensory characteristics of the selected muscles from Dohne Merino lambs, especially the tenderness of the Biceps femoris, which has a high retail value. On the other hand health conscious consumers will prefer extensively produced meat due to the favourable n3:n6 ratio, intramuscular fat content and the presences of less visible fat (subcutaneous). / AFRIKAANSE OPSOMMING: Hierdie studie was tweedoelig en is uitgevoer op die Biceps femoris, Longissimus dorsi en Semimembranosus spiere van Dohne Merino lammers (8 maande oud). Die eerste doel van die studie was om te bepaal wat die effek van ‘n ekstensiewe (weiding) en intensiewe produksie sisteem sal wees op vleis verbruikers se algemene kwaliteit voorkeure (fisiese eienskappe, chemiese samestelling, vetsuur profile, aroma, smaak, sappigheid, taaiheid,). Tweedens om te bepaal tot watse mate natuurlike oefening, verkry deur weiding asook beperkte beweging as gevolg van voerkraal omstandighede, die spier vesel tipe samestelling sal verander en die direkte impak van die samestelling op kwaliteit eienskappe van vleis. Lammers van die intensiewe produksie sisteem het ‘n betekenisvolle verhoging in uitslagpersentasie, onderhuidse vet dikte (13de rib en 3de/4de lende werwel) en vet ratio (karkas samestelling) getoon. Die vleis van die lammers het meer (p < 0.050) C20:3n6, C20:5n3 en C22:5n3 vetsure bevat asook ‘n hoër n3:n6 ratio gehad. Lammers van die ekstensiewe produksie sisteem het ‘n betekenisvolle hoër slag en koue karkas gewig gehad. Die vleis van die lammers het meer (p < 0.050) mioglobien bevat as intensiewe lammers. Resultate van die studie dui aan dat die vleis van lammer van die intensiewe produksie sisteem meer gunstige sensories karakteristiek produseer in vergelyking met lammers van die ekstensiewe produksie sisteem, asook ‘n betekenisvolle verhoging in sensoriese sagtheid van die Biceps femoris spier. Die Biceps femoris was die spier in die studie wat die meeste geaffekteer was deur die behandeling (produksie sisteme). Die Biceps femoris spier van intensiewe lammers het meer intramuskulêre vet en tipe IIB spier vesels bevat teenoor die Biceps femoris van ekstensiewe lammers wat meer onoplosbare kollageen en tipe I spier vesels bevat het. Gedurende die tekstuur profiel analise (instrumentele sagtheid toets) het die Longissimus dorsi en Semimembranosus van ekstensiewe lammers a hoër kompressie krag vereis, wat aandui dat die spiere taaier is as die ooreenstemmende spiere van intensiewe lammers. Die resultate van die studie voorsien ons met waardevolle insig in die inpak van verskeie produksie sisteme op die kwaliteit van lams vleis. Die afleiding kan gemaak word dat die implementering van intensiewe produksie sisteem die sensoriese kwaliteit van die spiere van Dohne Merino lammers verbeter, veral die sagtheid van die Biceps femoris spier, wat ‘n hoë kommersiële waarde het. Laastens, gesondheidsbewus verbruikers sal verkies om vleis te koop van ekstensiewe lammers weens die gunstige n3:n6 ratio, spier vetinhoud en die minder sigbare vet (onderhuidse vet) op die vleis.

Resumo: O efeito do método de embarque e desembarque nas características da qualidade da carne e nos níveis sanguíneos de estresse foi avaliado em suínos provenientes de três linhagens genéticas (A, B, C) comercializadas no Brasil. Um total de 120 suínos machos, pesando em média 115Kg provenientes de três granjas apresentando distância do frigorífico variando de 100 a 120Km foram divididos em seis grupos (n= 20 suínos) e submetidos a dois tipos de veículos para o transporte. O veículo 1 possui um sistema de embarque e desembarque, com carroceria com piso móvel (E1) e o veículo 2 apresenta o embarque e desembarque convencional, com carroceria com piso fixo (E2). Para a avaliação da qualidade da carne utilizou-se as características físico-químicas (pH, cor, perda por exsudação e capacidade de retenção de água) e para os níveis de estresse no sangue, foram determinadas as concentrações de cortisol, lactato e creatina fosfoquinase. Os valores médios obtidos para o pH24h (5,60±0,046 e 5,57±0.046), cor L*24h(41,52±1,256 e 41,21±1,486), perda por exsudação (4,76±0,391 e 4,86±0.391) e capacidade de retenção de água (0,038±0,03 e 0,039±0,003) não demonstraram diferença significativa entre os métodos de embarque e desembarque (E1 e E2) nas genéticas A, B e C. Os dados da incidência de escoriações de pele no pernil (0,59±0,090; 0,531± 0,090), corpo (0,896±0,076; 0,757±0,076) e paleta (0,612±0,050; 0,531±0,050) também não diferiram entre os métodos de embarque e desembarque nas genéticas A, B e C. Constatou-se diferença (p<0,05) na concentração de cortisol entre os métodos de embarque e desembarque (E1 e E2), no entanto, os níveis de lactato e creatina fosfoquinase não diferiram significativamente. Níveis menores de cortisol plasmático (p<0,05) foram encontrados na linhagem genética A, quando comparada a B e C. Conclui-se ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The effect of loading and unloading methods on meat quality and on blood stress levels were evaluated in pigs from three genetic lineage (A, B, C) marketed in Brazil. 120 male pigs, weighing 115Kg on average, from three different farms whose distance from the slaughterhouse ranged from 110Km to 120Km, were divided in 6 groups (n=20 pigs) and subjected to two kinds of vehicle for transport. Vehicle 1 has loading and unloading system, with mobile floor body (E1) and vehicle 2 has conventional loading and unloading system, with fixed floor body (E2). For the evaluation of meat quality, physiochemical characteristics have been used (pH, color, drip loss, water holding capacity) and for blood stress levels, concentrations of cortisol, lactate and creatine phosphoquinase. The obtained results for pH24h (5,60±0,046 and 5,57±0.046), color L*24h(41,52±1,256 and 41,21±1,486), drip loss (4,76±0,391 and 4,86±0.391) and water holding capacity (0,038±0,03 and 0,039±0,003) haven't shown meaningful difference between the kinds of loading and unloading methods (E1 and E2) on the genetics A, B and C. The data about incidence of skin damage on the ham (0,59±0,090; 0,531± 0,090), body (0,896±0,076; 0,757±0,076) and shoulder blade (0,612±0,050; 0,531±0,050) , have not differed between loading and unloading methods in genetics A, B and C, either. Difference in cortisol concentration (p<0,05) has been found out between loading and unloading methods (E1 and E2). However, lactate and creatine phosphoquinase levels haven't differed meaningfully. Lower plasmic cortisol levels (p<0,05) were found in genetic lineage A, when compared to B and C. It has been concluded that the loading and unloading methods had effects on stress levels but they were not enough to cause alterations in meat quality. / Orientador: Roberto de Oliveira Roça / Coorientador: Expedito Tadeu Facco Silveia / Banca: Osmar Antonio Dalla Costa / Banca: Jacinta Diva Ferrugem / Banca: Dirlei Antonio Brito / Banca: José Paes de Almeida Nogueira Pinto / Doutor

Resumo: A mais recente preocupação quanto à qualidade da carne de frango está associada a características musculares similares a carne pálida, mole e exsudativa (PSE) verificada em suínos. Carne de frango com características indicativas de PSE pode ser detectada pela combinação dos valores de pH (abaixo de 5,8) e cor (valor L* acima de 52,0) medidos 24 horas post mortem. Neste trabalho, o objetivo foi estimar herdabilidades, correlações genéticas e valores genéticos para características de desempenho corporal; pH aferido 15 minutos (PH15) e 24 horas (PH24) após o abate, medida da luminosidade da carne (L*), da cor vermelha (a*) e da cor amarela da carne (b*) de aves pertencentes à terceira geração do cruzamento recíproco entre uma linhagem de corte e uma de postura, desenvolvidas na Embrapa Suínos e Aves, em Concórdia, SC. Com o intuito de caracterizar a variabilidade dos valores genéticos dos animais para as características estudadas, estes foram submetidos à análise exploratória, utilizando técnicas estatísticas multivariadas de agrupamento hierárquico e não hierárquico (k-means) e análise de fatores. Os parâmetros genéticos foram estimados pelo método de máxima verossimilhança restrita. As estimativas de herdabilidade para as medidas de cor (L*, a* e b*) e pH indicaram que grande parte da variância fenotípica destas características pode ser atribuída aos efeitos não aditivos dos genes e ao ambiente, e, conseqüentemente, que a seleção para estas características não seria eficiente. O PH15 e L* apresentaram associação genética moderada com peso corporal, dessa forma, animais selecionados para peso corporal podem apresentar fenótipo de carne PSE, devido à redução do pH e ao aumento da palidez da carne. Não foi observada associação genética entre L* e as medidas a* e b*. Pela análise de agrupamento hierárquico pôde-se perceber a formação de ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The most recent concern about the quality of chicken meat is associated with characteristics similar to pale, soft and exudative meat (PSE) found in pigs. Chicken meat with PSE's characteristics can be detected by the combination of pH values (below 5.8) and color (L * value greater than 52.0) measured 24 hours post mortem. The objective of this research was to estimate heritabilities, genetic correlations and breeding values for body weight (WT), carcass traits, pH measured at 15 minutes (PH15) and at 24 hours (PH24) after slaughter, measurements of brightness (L*), red color (a*) and yellow color (b*) of the poultry meat belonging to the third generation of a reciprocal cross between a meat and a posture line developed at Embrapa Suínos e Aves, Concórdia, SC. In order to evaluate the breeding values variability of traits, these estimates were submitted to exploratory analysis, using multivariate statistical techniques of clustering, k-means and factor analysis. The estimation of the genetic parameters was performed using restricted maximum likelihood method. The heritability estimates for measures of color (L*, a* and b*) and pH indicated that much of the phenotypic variance of these traits can be attributed to non-additive effects of genes and environment. Therefore the selection for these traits would not be considered efficient. The PH15 and L* were moderate genetic correlated with body weight. Consequently animals selected for body weight may have phenotype of PSE meat due to reduced pH and paler meat. No genetic association was found between L* and a* and b* measures. The cluster analysis showed the formation of four distinct groups in the studied population in relation to the breeding values. In factor analysis, four factors were taken into account. The first factor included the performance body traits, which is responsible for 51.26% of the total variation of breeding values ... (Complete abstract click electronic access below) / Orientador: Danísio Prado Munari / Coorientador: Mônica Corrêa Ledur / Banca: João Ademir de Oliveira / Banca: Marcelo Henrique de Faria / Mestre

The broad objective of the study was to investigate the effect of post-slaughter handling in the distribution chain on red meat quality and safety. A survey was conducted among 300 consumers and 100 meat handlers in five different municipalities (Buffalo City, Nkonkobe, Ngqushwa, Lukhanje and Amahlathi) in the Eastern Cape Province of South Africa to investigate their perceptions on meat quality and safety, together with challenges faced by meat handlers during the distribution of meat from the abattoir to retailers. The microbiological profile and physico-chemical quality of red meat at different stages of the abattoir to retail outlets in the distribution chain were also determined. Swabs (n=216) and meat samples (n=450) were collected from beef, pork and mutton carcasses during the loading process of carcasses into trucks at the abattoir, when offloading carcasses at the supply points and during marketing. Physico-chemical qualities such as colour (L* - lightness, b* - redness and a* - yellowness) and meat pH measurements were taken at each point. To determine the microbiological profiles of the carcasses, four microbiological parameters were considered: Total bacteria count (general bacteria), coliform count (related to hygiene and indicator for pathogens), Escherichia coli (Gram-negative pathogen) and Staphylococcus aureus (Gram-positive pathogen). Two types of packaging (vacuum and overwrapping) were used to determine their effect on shelf-life and microbiological quality of red meat under the normal marketing conditions over a storage duration of 15 days. The results from the study showed low awareness of consumers about the pathogenic diseases which arise from meat. A strong significant association (p ˂ 0.05) between educational status and awareness on meat safety was observed. Most of the consumers perceived that quality goes beyond safety such that 35.6 percent of the respondents indicated that they did not have a problem with consuming spoiled meat, whilst the remaining 64.4 percent indicated that they would r eject spoiled meat. Although retailers indicated that they take meat safety into consideration in their shops, 92 percent of the retailers revealed that they do not perform microbial assessment of meat in their shops. A series of loading and off-loading, temperature fluctuations, environmental temperatures and ques during offloading were reported as the major challenges during transportation of carcasses from the abattoir to the supply points. The microbial counts were significantly (p<0.05) higher in samples from the commercial abattoir than in those from the communal abattoir. Escherichia coli was the predominant microbial contaminant in the samples from both abattoirs. When following the chain, total bacterial count (TBC), coliform count (CC) and the levels of E. coli contamination increased progressively between the loading and the off-loading points (5.1 to 7.9 log10 CFU/cm2; 5.0 to 5.6 log10 CFU/cm2 and 2.7 to 3.7 log10 CFU/cm2, respectively). The storage period, meat type, distance during transportation and temperature were found to have a significant impact on the microbial levels during the distribution of carcasses. Distribution stage had a significant effect (p<0.05) on some of the physico- chemical meat quality attributes and differences in the lightness (L*) and redness (a*) values between the loading, off-loading and display points were observed. Consumers perceived retailer class as one of the factors influencing meat quality, but according to the instrumental measurements retailer class did not have a significant effect on physico-chemical meat quality. However, distance and storage duration significantly (p<0.05) affected (L*) and (a*) values in the meat during distribution chain. Vacuum and overwrapping packaging significantly affected (p<0.05) the shelf life of meat. Therefore, it was concluded that post-slaughter handling during the distribution chain affects the physico- chemical, microbiological and shelf-life of meat.

Este estudo objetivou avaliar a utilização da ultrassonografia no diagnóstico in vivo de wooden breast (WB) em frangos de corte submetidos à restrição alimentar. Foram utilizados 1.800 frangos de corte machos Cobb x Cobb 500 distribuídos em 6 tratamentos, com 12 repetições de 25 aves cada, em um delineamento inteiramente casualizado. Os tratamentos consistiram em restrições de 50, 60, 70, 80, 90% da quantidade de ração fornecida em relação ao consumo ad libitum diário do tratamento controle, de 8 a 49 d. Semanalmente, as aves foram pesadas para avaliação de desempenho e foram submetidas à ultrassonografia para determinar a ecogenicidade do peito, em que os valores de cinza foram calculados a partir do histograma gerado de cada imagem. A profundidade do peito também foi mensurada. Semanalmente, de 7 a 49 d, uma ave por unidade experimental (UE) foi abatida para avaliação visual dos escores de WB, bem como para coleta de amostras de peito para análises sorológicas e de qualidade de carne. Aos 49 d, foram abatidas 5 aves por UE para avaliação do rendimento de carcaça, cortes comerciais e ocorrência de WB Os peitos foram avaliados em escores: peito normal (0); endurecimento suave na parte cranial (1); endurecimento da parte cranial e caudal (2); endurecimento severo de todo o peito (3), endurecimento severo com presença de lesões hemorrágicas e exsudato (4). O efeito das restrições alimentares sobre desempenho e os escores de WB foi avaliado através da análise de variância. Os escores de WB foram considerados variáveis independentes e também correlacionados com as medidas de ultrassom do peito, qualidade de carne, medidas histomorfométricas e perfil sorológico das aves. O desempenho produtivo e a ocorrência de WB reduziram linearmente (P < 0,05) com as restrições alimentares mais severas. Os valores de ecogenicidade e profundidade do peito aumentaram (P < 0,05) com a severidade de WB. De 21 a 49 d, peitos com escores 3 e 4 apresentaram maior perda por cocção, diâmetro de fibra e concentração das enzimas marcadoras de lesão muscular (P < 0,05) comparados ao peito normal (escore 0). A ultrassonografia do peito de frangos de corte pode ser uma ferramenta auxiliar no diagnóstico da miopatia WB em aves vivas. / The present study was conducted to evaluate the effectiveness of utilizing ultrasound (US) images of breast muscle to predict wooden breast (WB) myopathy in lived broilers subjected to different feed restrictions. A total of 1,800 Cobb × Cobb 500 male chicks were fed with 6 treatments and 12 replicates of 25 birds each using a completely randomized design. Birds were fed ad libitum or received 50, 60, 70, 80, and 90% of the quantity consumed by the chickens fed ad libitum. The restriction programs were applied from 8 to 49 d. All birds were banded on the first day and every week they were weighted in order to determined BWG, FCR and FI. Ultrasound images of breast muscle were weekly obtained from all birds to determine echogenicity, where mean gray values were calculated from the obtained histogram, and the breast depth was also measured. One bird per experimental unit was slaughtered every week, from 7 to 49 d, for visual evaluation of WB scores, as well as breast samples collections for serum analysis and meat quality. At 49 d, 5 birds per experimental unit were slaughtered to evaluate carcass yields and WB occurrence Breast were evaluated as: normal breast (0), mild hardening in the upper (1), moderate hardening in the upper and/or lower part of the fillet (2), severe hardening (3), and severe hardening with hemorrhagic lesions and yellow fluid (4). The effect of feed restrictions on growth performance and WB scores was evaluated using ANOVA. The WB scores were considered independent variables and correlated with echogenicity, breast depth, meat quality, histomorphometric measurements and serologic profile of birds. Growth performance as well as carcass yield, decreased linearly (P > 0.05) as feed restriction was applied. The WB occurrence presented linear response to growth performance and it was lower on treatments with higher feed restrictions. Echogenicity and depth increased with WB severity (P < 0.05). From 21 to 49 d, the WB scores 3 and 4 also had higher cooking loss, fiber diameter, serum enzymes, whereas fiber density per area was lower (P < 0.05) compared to normal breasts (score 0). Ultrasound images of broilers breast can be adequately utilized to predict in vivo the WB of birds.