Beef cattle producers continuously search for nutritional management options that provide flexibility to production scenarios. Due to its positive effects on maternal productivity, early weaning is one such alternative strategy that has received considerable interest. To better understand the effects of early weaning on calf productivity, an extensive literature review and three experiments were conducted to evaluate the effects of early weaning on finishing feed efficiency, marbling development and retail product quality of beef steers. In experiment I, which included 90 Angus-sired steers from four calving seasons, early weaning followed by a short ad libitum concentrate-feeding and pasture-backgrounding phase reduced finishing residual feed intake (RFI) by 7 % (P < 0.0001) and increased carcass marbling score (MS) by 10 % (P < 0.01) when compared to conventionally weaned (CW) contemporaries. Similar effects were observed in experiment II, which included 28 Angus and Simmental-sired steers, as early weaning reduced RFI (P < 0.01) and increased carcass MS (P < 0.01). Lung mass of early weaned (EW) steers was greater than their CW contemporaries (P < 0.05), and was inversely related to RFI (R2 = 0.17; P < 0.05). Finishing treatments in this experiment included a high corn ration and an alternative low corn ration that iso-calorically replaced 50 % of the DM from corn with dried corn gluten feed. Iso-caloric replacement of corn reduced lung mass (P < 0.01), and when combined with the observed increase of EW steers suggests that lung development is affected by dietary energy type at various stages of growth. In experiment III, objective analyses of ribeye steaks obtained from steers included in experiment two revealed that early weaning increased cross-sectional muscle fiber area by 28 % (P < 0.001) and tended to increase (P = 0.08) Warner-Bratzler shear force by 36 %. Nonetheless, these effects were not great enough to alter un-trained consumer perception of texture (P ≥ 0.65), juiciness (P ≥ 0.55), flavor (P ≥ 0.25) or overall acceptability (P ≥ 0.34). Collectively, these results indicate that early weaning enhances finishing feed efficiency and carcass marbling without affecting un-trained consumer sensory perception. / Ph. D.

Master of Science / Department of Animal Sciences and Industry / Travis G. O'Quinn / The objective of this study was to evaluate the impact of quality grade on beef eating quality of top sirloin steaks when cooked to multiple degrees of doneness (DOD). Beef top sirloin butts (N = 60; 15 / quality grade) were collected to equally represent 4 quality grades [Prime, Top Choice (modest00 – moderate100), Low Choice, and Select]. Top butts were cut into six consecutive steaks, and then divided laterally to get a total of twelve steaks per top butt. Steaks were assigned to one of three DOD: rare (60°C), medium (71°C), and well-done (77°C). Steaks within DOD were assigned to consumer sensory analysis, trained sensory analysis, fat and moisture analysis, and Warner-Bratzler shear force (WBSF). There were no interactions (P > 0.05) for all consumer ratings of palatability traits, indicating increases in DOD had the same impact across all quality grades. There was a difference (P > 0.05) within quality grade for consumer ratings of juiciness (P > 0.05). Prime steaks had greater (P < 0.05) juiciness ratings than all other quality grades, except for Top Choice. As DOD increased, consumer ratings and the percentage of steaks rated acceptable for each palatability trait decreased (P < 0.05; rare > medium > well-done). There was a quality grade × DOD interaction (P < 0.05) for trained sensory panel juiciness scores. When cooked to medium, Prime and Top Choice steaks were rated higher (P < 0.05) for juiciness than Low Choice and Select steaks. Similar to consumer ratings, trained panel ratings of tenderness decreased (P < 0.05) as DOD increased (rare > medium > well-done). Lastly, there were no quality grade by DOD interactions (P > 0.05) for Warner-Bratzler shear force. These results indicate that regardless of the DOD steaks were cooked to, quality grade had minimal impact on the palatability of beef top sirloin steaks. Therefore, unless cooked to a medium DOD, it is unnecessary for consumers, retailers, and foodservice to pay premium prices for higher quality top sirloin steaks, as the same eating experience will be given.

<p>Rapporten finns arkiverad i fulltext (pdf) i DiVA och kan hämtas av administratör</p>

Bos indicus influenced primiparous heifers (n = 300) and yearling Beefmaster heifers (n = 172) were evaluated to determine relationships between serial carcass ultrasound traits and ability to breed in short (45 to 90 d) breeding seasons. Data collected included carcass ultrasound traits: ribeye area (REA), intramuscular fat (IMF), rump fat (UFAT), ribfat, weight, and body condition score taken at yearling age, pregnancy determination, before breeding, and after the breeding season when pregnancy status was recorded. A logistic regression analysis was used to determine the influence of ultrasound traits and body condition on pregnancy status. Odds ratios suggested the likelihood of primiparous cattle rebreeding would have been increased by 93% if IMF would have averaged 3.5% instead of 2.5% as yearlings, or an increase in the average ribfat as yearlings from 0.287 to 0.387 cm would have increased the odds of rebreeding by 88%. Increased average body condition score of 6.5 rather than 5.5 at 30 days postpartum in primiparous cows was estimated to have increased rebreeding 367%. The odds of yearling Beefmaster heifers successfully breeding during a 45-day season would have been increased by 73% (year 1) or 274% (year 2) by increasing REA 6.4 to 6.5 cm^2 at a year of age. Steers were serially scanned beginning at approximately 265 kg of body weight through harvest in 56 day +/- 6 intervals. Data collected included ultrasound measurements (ribeye area (REA), 12th rib fat thickness (RibFat), percent intramuscular fat (IMF), and rump fat (UFAT)), weight, and carcass data. Days to choice was calculated for each steer based on a linear regression. The IMF deposition was quantified as quadratic from scans 1-6 and linear when cattle were on full feed. Prediction models at scans 1, 2, 3, 4, 5, and 6 yielded R-square values of 0.20, 0.25, 0.41, 0.48, 0.59, and 0.49, respectively for days to choice. Odds ratios suggested that if steers in this study had averaged 3.78% at day 0 rather than 2.78, the odds of cattle grading premium choice or greater would have been increased by 300%.

Submitted by la_simielli@yahoo.com.br (la_simielli@yahoo.com.br) on 2016-04-05T13:12:40Z No. of bitstreams: 1 TESE_LARISSA_FERNANDA_SIMIELLI_FONSECA.pdf: 1971633 bytes, checksum: 177f6a3044467459f559bbf217ba550f (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-04-06T20:32:27Z (GMT) No. of bitstreams: 1 fonseca_lfs_dr_jabo.pdf: 1971633 bytes, checksum: 177f6a3044467459f559bbf217ba550f (MD5) / Made available in DSpace on 2016-04-06T20:32:27Z (GMT). No. of bitstreams: 1 fonseca_lfs_dr_jabo.pdf: 1971633 bytes, checksum: 177f6a3044467459f559bbf217ba550f (MD5) Previous issue date: 2016-03-07 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Mais de 80% da carne bovina brasileira é proveniente de animais de origem zebuína. Este produto é considerado de baixa maciez e reduzido teor de gordura entremeada quando comparado à carne de animais de raças taurinas. Investir na melhoria das características organolépticas como marmoreio e maciez da carne torna-se importante do ponto de vista econômico, pois tratam-se de atributos muito apreciados pelo consumidor. A maciez pode ser medida por meio de análises sensoriais, índice de fragmentação miofibrilar ou força de cisalhamento. Nesse último, um aparelho é utilizado para medir a força necessária para o cisalhamento de uma seção transversal de carne e, quanto maior a força dispensada, menor é a maciez apresentada pelo corte de carne. Outra característica relacionada à qualidade da carne é o marmoreio, que pode ser analisada por meio de escala de graduação visual denominada Quality Grade. No entanto, estas metodologias só podem ser utilizadas após o abate do animal. As técnicas de análise do transcriptoma, como o RNA-Seq, permitem a identificação de genes cuja expressão está relacionada com o controle de características quantitativas e podem ser alternativas na busca pelo melhoramento destes atributos. Com isso, o objetivo deste trabalho foi identificar genes diferencialmente expressos utilizando a técnica RNA-Seq, em tecido muscular de bovinos da raça Nelore, visando contribuir para o conhecimento dos fatores genéticos que estão relacionados com a qualidade da carne. Para isso, foi sequenciado o mRNA de 40 amostras divergentes para a maciez da carne (20 com carne dura e 20 com carne macia) e 40 amostras divergentes para marmoreio (20 com alto e 20 com baixo marmoreio). Essas amostras foram escolhidas com base na análise de força de cisalhamento e índice de marmorização realizadas em 132 e 80 amostras de músculo longissimus dorsi respectivamente, coletadas da meia carcaça esquerda de cada animal. As análises dos resultados obtidos pela técnica de RNA-Seq revelaram genes diferencialmente expressos relativos à maciez e marmoreio da carne em gado Nelore. Os genes referentes à maciez estão relacionados ao metabolismo de colágeno, à actina e miosina, ao transporte de cálcio, dentre outros. Por outro lado, nos resultados das análises de marmoreio, os genes que se mostraram diferencialmente expressos estão relacionados à ocitocina, ao transporte de oxigênio, ao crescimento e à síntese de lipídios e proteínas. Portanto, este estudo revelou a possibilidade de se utilizar alguns desses genes diferencialmente expressos como marcadores genéticos em bovinos Nelore para seleção precoce quanto à maciez e marmoreio da carne. / More than 80% of Brazilian beef comes from zebu animals. The Zebu meat show reduced marbling and is considered harder when compared to Taurine meat. The improvement of the organoleptic traits like marbling and meat tenderness is important from an economic point of view, because these attributes are highly appreciated by the consumer. The meat tenderness can be measured by sensory analysis, myofibril fragmentation index or by shear force. This method use an apparatus which measure the force required to shear a cross section of meat. The higher the strength dispensed, lower is the tenderness showed by the cut of meat. Another trait related to meat quality is marbling, which can be analyzed by Quality Grade visual graduation scale. However, these methods can only be performed after the animal was killed. The transcriptome analysis techniques, as RNA-Seq, are able to identify genes whose expression are related to quantitative traits control and can be used as alternative to help the improvement of these traits. Thus, the aim of this study was to identify differentially expressed genes using RNA-Seq, in Nelore cattle muscular tissue, to contribute to the knowledge of the genetic factors that are related to meat quality. We sequenced the mRNA of 40 samples divergently ranked to meat tenderness (20 with hard meat and 20 with tender meat) and sequenced the mRNA of 40 samples divergently ranked to marbling (20 with high and 20 with low marbling). These samples were chosen based on shear force and marbling content analysis held at 132 and 80 longissimus dorsi muscle samples respectively, collected from each left half carcass. The analysis of the results obtained by RNA-Seq technique revealed differentially expressed genes related to meat tenderness and marbling in Nelore cattle. Regarding the meat tenderness, these genes are related to collagen metabolism, actin and myosin, the calcium transport, among others. Moreover, the marbling analysis results, revealed differentially expressed genes related to oxytocin, transport of oxygen, growth and lipids and proteins synthesis. Therefore, this study showed the possibility of using some of these differentially expressed genes as genetic markers in Nellore cattle for early selection to meat tenderness and marbling. / FAPESP: 2013/09190-7

Master of Science / Department of Animal Sciences and Industry / Travis G. O'Quinn / The objective of this research was to evaluate the role of marbling texture on beef palatability, muscle histology, and collagen characteristics of beef strip loin steaks. Beef strip loins (n = 117) were selected from three quality grade treatments [Top Choice (Modest[superscript 00] – Moderate[superscript 100] marbling), Low Choice (Small[superscript 0] – Small[superscript 100] marbling), and Select (Slight[superscript 0] – Slight[superscript 100] marbling)] to equally represent three different marbling texture groups: fine, medium and coarse, via visual appraisal with the USDA marbling texture standards. Consumers (n = 104) rated all marbling texture groups similar (P > 0.05) for tenderness, juiciness, flavor, and overall liking, as well as rated a similar (P > 0.05) percentage of samples from each marbling texture group acceptable for each palatability trait. Moreover, consumers indicated no preference (P > 0.05) among marbling texture groups for visual desirability or likelihood to purchase. There were no differences (P > 0.05) among marbling texture treatments for Warner-Bratzler shear force, slice shear force, and pressed juice percentage. However, trained sensory panelists rated coarse marbled steaks higher (P < 0.05) than fine or medium marbled steaks for both beef flavor intensity and sustained juiciness as well as higher (P < 0.05) for initial juiciness than medium textured steaks. This minimal impact on palatability was further supported through evaluation of muscle histology and collagen traits. Marbling texture did not affect collagen characteristics, as coarse marbled steaks were similar (P > 0.05) to both fine and medium marbled steaks for soluble collagen, insoluble collagen, and total collagen content. Furthermore, all marbling texture groups (fine, medium, and coarse) performed similarly (P > 0.05) during the peak thermal transition phase of the perimysial fraction of collagen. However, marbling texture impacted (P < 0.05) adipocyte cross-sectional area, where coarse steaks had larger adipocytes in comparison to fine marbled steaks, but medium marbled steaks were similar (P > 0.05) to both coarse and fine marbled steaks. Similarly, quality grade affected adipocyte size, as Top Choice and Low Choice possessed larger (P < 0.05) adipocytes than Select steaks. However, marbling texture did not impact (P > 0.05) perimysial thickness. Additionally, marbling texture did not affect the percentage of myosin heavy chain (MHC) Type I fibers within each steak. However, medium marbled steaks possessed a greater (P < 0.05) percentage of MHC Type 2A fibers than both fine and coarse marbled steaks. The opposite trend was displayed in the percentage of MHC Type IIX fibers, as fine and coarse marbled steaks possessed more (P < 0.05) MHC Type IIX fibers in comparison to medium marbled steaks. There were no differences (P > 0.05) among quality grades for fiber type or marbling texture and quality grade for fiber cross-sectional area. Results from this study indicate marbling texture has minimal impact on eating quality and muscle histology; therefore coarse marbled carcasses should not be excluded from current and future branded beef programs.

Objetivou-se neste trabalho avaliar algumas características da carne de bovinos Nelore, analisando as diferenças entre as progênies (machos e fêmeas) de touros representativos das principais linhagens desta raça e comparar as progênies (machos e fêmeas) dos grupos genéticos Nelore, ½ Angus x Nelore e ½ Brahman x Nelore. Quartorze touros, raça Nelore, dois Aberdeen Angus e um Brahman foram acasalados com 400 vacas comerciais da raça Nelore formando progênies de Nelore (NE), ½ Aberdeen Angus x Nelore (AN) e ½ Brahman x Nelore (BN). Os animais foram confinados por 127 dias, recebendo alto teor de concentrado. Foram abatidos 293 bovinos, determinados o pH e a temperatura das carcaças e avaliados o grau de acabamento das carcaças. Após 24 horas de resfriamento calculou-se o rendimento das carcaças (RC), a área de olho de lombo (AOL) a espessura de gordura subcutânea (EGS) e foi determinado o índice de marmorização no m. Longissimus dorsi. Retiraram-se duas amostras desse músculo, as quais foram maturadas por 14 dias para as análises de força de cisalhamento (FC), perda de água por exsudação (PAE), perdas ao cozimento (PAC) e índice de fragmentação miofibrilar (MFI). Houve interação entre sexos e gupos genéticos para as características de peso vivo final (PVF), rendimento de carcaça (RC) e área de olho de lombo (AOL). Houve diferenças entre sexos e grupos genéticos para o peso de carcaça quente (PCQ) e para a espessura de gordura subcutânea (EGS). A marmorização e a força de cisalhamento foram influenciadas pelos grupos genéticos. O pH, e a temperatura (1 hora pós-morte) não foram influenciados pelos sexos e grupos genéticos, assim como as perdas ao cozimento (PAC) e o índice de fragmentação miofibrilar (MFI). O sexo influenciou nas características de acabamento das carcaças, pH e temperatura (24 horas pós-morte) e nas perdas de água por exudação (PAE). Quando analisadas as diferenças entre as progênies de touros representativos das principais linhagens da raça Nelore houve interação entre sexo e touros para o PVF, PCQ e EGS. Houve diferenças entre sexos e touros para as características de acabamento, RC, AOL e marmorização. Não foram detectadas diferenças entre sexos e entre touros para o pH e temperatura (1 hora pós-morte), PAC e maciez por meio da força de cisalhamento. O sexo influenciou o pH e a temperatura (24 horas pós-morte), assim como a PAE e o MFI do m. Longissimus dorsi maturado por 14 dias também foram influenciados. Constatou-se superioridade dos animais cruzados, em relação aos zebuínos puros, quanto a algumas características de qualidade da carne, com variação dentro da raça Nelore. Foram identificados touros, cujos filhos produziram carne com os melhores padrões de qualidade para o mercado mundial. / This work aimed to evaluate some meat characteristics of Nellore cattle. The differences among the progenies (males and females) of representative sires of the main lines of this breed and also of Nellore, ½ Angus ½ Nellore and ½ Brahman ½ Nellore genetic groups were analyzed. Fourteen Nellore, two Aberdeen Angus and one Brahman bull, were mated to 400 Nellore cows to obtain the Nellore, ½ Angus ½ Nellore and ½ Brahman ½ Nellore progenies. The animals were fed on feedlot during 127 days with high concentrate diets and after the slaughter of 293 animals the pH, temperature and classification of the carcass was performed. After 24 hours chilling the carcass dressing percentage, rib eye area, fat thickness and marbling index of the Longissimus dorsi m. were determined. Two samples of this muscle were collected and aged during 14 days for shear force, water loss, cocking loss and myofribrilar fragmentation index (MFI) determination. There was an interaction between sex ad genetic groups for final live weight, carcass dressing percentage and rib eye area. There were differences between sex and genetic groups in carcass weight and fat thickness. Marbling and shear force were affected by genetic group. The pH and the temperature one hour after slaughter were not affected by sex and genetic group, as well as cocking loss and myofibrilar fragmentation index. Sex affected the finishing characteristics of the carcass, the pH and temperature 24 hours after slaughter and the water loss. Among the progeny of Nellore sires there was an interaction between sex and bull for final live weight, carcass weight and fat thickness. There were differences between sex and sires in the finishing characteristics, carcass dressing percentage, rib eye area and marbling. No differences were detected between sex and sires in pH and temperature one hour after slaughter, cocking loss and tenderness with Warner Bratzler Shear Force. Sex affected pH and temperature 24 hours after slaughter, as well as water loss and MFI of the Longissimus dorsi m. were affected. It was observed superiority of the crossbred steers in some meat quality characteristics, but also large variation inside the Nellore breed. The progeny of some Nellore sires produced meat with enough quality for the world market.

The purpose of this study is to investigate the effects of a marbled coating applied on a triaxial woven structure. Although both of these techniques are traditionally used for many years, they are nowadays utilized in innovative ways, the marbling being applied on a large variety of surfaces such as wooden floors or ceramics and the triaxial weave being used as a hi-tech material for sports or in the automotive industry and having applications in diverse fields, from art to architecture. Their fusion, however, is a topic that has yet to be thoroughly explored, which makes for the motive of this thesis work, as an opening has been observed for the exploration of the expressive power of their combination. The experimental approach that has been taken towards this exploration will determine how the marbling effect may contribute to the visual expression of the structure. Multiple cycles of experiments have been conducted in an attempt to understand the behaviour of the chosen materials and their combination, the effect that various colour combinations have and the best possible pairings between the elements. The organic marbling combined with the geometric triaxial weave proved to generate the most powerful visual expression and the clearest result out of all the experiments. Thus five experimental textiles were developed in order to illustrate different aspects of this complex relationship, where the marbling would affect the visual expression of the structure by either enhancing or concealing the structural aspect and the contrast between the graphic element and the organic one would be a constant presence throughout the work. This work pushes the boundaries of conventional textile design and through the application of a textile thinking to unconventional materials a different type of expression is born. By mixing a limited amount of variables in multiple ways, a large range of visual effects may be achieved.

Biochemical changes in muscle postmortem have been associated with initial beef tenderness early postmortem, and with improvements in tenderness during postmortem storage, defined as meat aging. Differences in the initial contractile state of the sarcomere, the ionic environment of the sarcoplasm including pH, the activity of neutral proteolytic enzymes, and collagen content and solubility have been associated with beef tenderness. In Phase I, steaks from four genetic lines of steers and heifers were used to understand the biochemical differences between tough and tender steaks. The most tender (< 30 N Warner Bratzler shear force (WBS)) and toughest Longissimus steaks (< 30 N WBS) from Angus, Braford, Brangus, and Simbrah heifers and steers were used. For Phase II, samples were obtained from a subset of Santa Cruz yearling heifers selected based of genotypes for tenderness (tough and tender) using a commercial genetic marker. Within genotype for tenderness, each animal was randomly assigned to one of four growth enhancement treatments. The most tender (< 30 N WBS) and toughest Longissimus steaks (< 30 N WBS) were selected for use in this study. In Phase I, tough steaks after 3, 10, and 17d postmortem had higher (P < 0.0005) WBS values than tender steaks. Tender steaks came from carcass with slightly higher (P = 0.008) marbling score and (P = 0.01) Quality grade. Sarcomere length, total and soluble collagen, potassium concentration, and m and µcalpain did not differ (P > 0.05) between tough and tender steaks. Sodium concentration at 10 d was higher (P = 0.03) in tough steaks, but only account for 0.05% of the variation in WBS at 3d. Tender steaks had less (P = 0.04) intact desmin at 24h, but intact desmin was not correlated (P > 0.05) with WBS. In Phase II, tough steaks after 3, 10, and 17d postmortem had higher (P < 0.0001) WBS values than tender steaks. Tender steaks came from carcass with slightly higher (P < 0.03) marbling score and (P = 0.02) Quality grade. Tender teaks were slightly lighter (P = 0.02), with more red (P = 0.02) and yellow (P = 0.007) color, and had slightly lower (P = 0.02) pH, compared with tough steaks. Sarcomere length, total and soluble collagen, sodium and potassium concentration, and m and µcalpain did not differ (P > 0.05) between tough and tender steaks. Tender steaks had less (P < 0.0001) intact desmin at 17d postmortem than tough steaks. Intact desmin at 17d was responsible for 4%, 47%, and 30% of WBS variation after 3, 10, and 17d postmortem, respectively. The slight difference in marbling and quality grade did not account for a significant amount of variation in WBS. However, meat color and pH accounted for variation in shear WBS. Calcium flux may have influenced meat tenderness by activation of calpains and may have altered protein to protein interactions. Results suggested that marbling, µ calpain activity, and desmin degradation, and to a lesser extent pH and meat color contributed to meat tenderness.

Orientador: Prof. Dr. Mario Alexandre Gazziro / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Ciência da Computação, 2017. / Marmoreio em papel é um método de design principalmente utilizado por artistas desenvolvedores de capas de livros, no qual tinta a base de óleo é depositada sobre uma superfície aquosa, de forma a produzir padrões texturais semelhantes à do mármore. Os padrões são o resultado da flutuação dos pigmentos de tinta sobre a água definidos pelos movimentos manuais do artista que, em seguida, é cuidadosamente transferido para uma superfície de papel ou tecido absorvente. Apesar do fato de alguns sistemas digitais de marmoreio já terem sido desenvolvidos no passado, nenhum deles pôde fornecer simultaneamente uma interface natural ao usuário e uma simulação em tempo real. Este trabalho obteve a melhora do processo de marmoreio digital através de uma interface fácil de aprender, apresentando simultaneamente características de resposta rápida e de fácil navegação através de uma caneta digital, usando uma mesa digitalizadora como superfície de design, processando algoritmos na GPU por meio de programas shaders para os cálculos de dinâmica computacional de fluidos, envolvendo resolução em tempo real das Equações de Navier-Stokes. / Paper marbling is a design method mainly used by artists who develop book covers, in which is deposited oil-based paint on an aqueous surface in order to produce textured patterns like marble. The patterns are the result of the fluctuation of the ink pigments on the water defined by the artist¿s manual movements which is then carefully transferred to a surface o f absorbent paper or fabric. Although some digital marbling systems have already been developed in the past, none of them could simultaneously provide a natural user interface and real time simulation. This work improvement of the digital marbling process through an easy to learn interface, simultaneously presenting fast response characteristics and easy navigation through of a pen stylus, using a pen tablet as a design surface, processing GPU algorithms using shaders to calculate computational fluids dynamics, involving real time resolution of the Navier-Stokes equations.