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Uma das principais causas de prejuízos econômicos da pecuária mundial, é a mortalidade de bezerros nos primeiros meses de vida, devido ao desenvolvimento de afecções, pois a defesa contra estas, depende principalmente da imunidade destes animais. Nesta fase, os animais possuem seu sistema imune ainda não completamente funcional, além disso, o número de bezerros acometidos e a gravidade das doenças, pode variar de acordo com a raça dos bovinos. A literatura relata que os bezerros da raça japonesa Wagyu podem ser mais susceptíveis às afecções durante o período neonatal, quando comparados à bezerros da raça Holandesa. Porém, a maior susceptibilidade destes animais ainda não possui as razões totalmente elucidadas. Devido às consequências da menor competência imunológica dos bezerros japoneses, o desenvolvimento de estratégias para a melhoria da imunidade destes animais, vem sendo alvo de pesquisas e a utilização de antioxidantes, como a Vitamina E, é uma das tentativas para melhorar a imunidade desses neonatos. No presente trabalho, foram selecionados 26 bezerros da raça Wagyu, com média de 7,35 (±2,64) dias de vida, os quais foram distribuídos por dois grupos de 13 animais (Grupo Controle e Grupo Vitamina E). O Grupo Vitamina E recebeu uma aplicação de Vitamina E, por via intramuscular (30 UI/kg). O Grupo Controle recebeu uma aplicação intramuscular de solução de NaCl 0,9% no mesmo volume correspondente ao de Vitamina E, de acordo com o peso do animal. Os animais foram avaliados semanalmente, durante os primeiros 60 dias de vida, por meio de exame físico, hemograma, bioquímica sérica e avaliação da função de neutrófilos com uso da citometria de fluxo. Não houve diferença entre os grupos controle e Vitamina E em nenhum dos parâmetros avaliados. Os resultados de exames físicos, hemograma e bioquímica sérica dos bezerros Wagyu, apresentaram comportamento semelhante ao descrito na literatura, bem como, a maioria dos aspectos avaliados na função dos neutrófilos. A aplicação de Vitamina E na dosagem de 30UI/kg não gerou alteração na função dos neutrófilos, a partir da avaliação da produção de espécies reativas de Oxigênio (EROs) pelos granulócitos, estimulados ou não pela fagocitose de Staphylococcus aureus conjugado com Iodeto de propídeo (SaPI). Existe a necessidade do desenvolvimento de novas pesquisas, a respeito de dosagens de Vitamina E capazes de gerar alterações na função de neutrófilos dos bezerros Wagyu, afim de melhorar o perfil imunológico destes animais.

One of the main causes of economic losses of livestock worldwide, is the mortality of calves in the first months of life, on account of diseases, because the immunity of these animals is a very important for their defense. At this stage, the animals have their immune system not yet fully developed, in addition, the number of calves affected and the severity of the diseases, can vary according to the breed of the cattle. The literature reports that Japanese Wagyu calves may be more susceptible to conditions during the neonatal period, in comparison…

Advisors/Committee Members: Fernando José Benesi, Milton Ricardo Azedo, Camila Freitas Batista.

▼ The objective of this study was to investigate the effect of roughage inclusion rate of 10, 20, and 30% within a total mixed ration on feedlot performance, carcass composition and marbling distribution in Wagyu cattle (n=41). Upon arrival, cattle were acclimated to bunk style feeding. Initial body weights were collected. Animals were blocked by sex and weight to be assigned to 1 of 3 roughage inclusion rate treatments. Treatments included 1) 10% roughage inclusion on dry matter basis; 2) 20% roughage inclusion and 3) 30% roughage inclusion on dry matter basis. Diets were formulated to be isoenergentic, isonitrogenous, and isoamylolytic. Animals were weighed every 7d. For harvest animals were transported to a commercial abattoir. Hot carcass weight (HCW) was determined at time of harvest, intramuscular adipose, and subcutaneous adipose tissue was collected at harvest and snap frozen for analysis of FA composition. Longissimus muscle area (LMA) and backfat (BF) carcass measurements were determined after 21d storage at 0° C chill. A 1.25 cm cross section of longissimus dorsi at 12th and 13th rib interface was collected for Computer Vision System Ribeye Camera evaluation of marbling distribution. Limited treatment effects were observed. Feedlot performance and carcass characteristics were not significantly affected by roughage inclusion rate (P>0.05). Treatment presented a significant effect on Linoleic acid (C18:3) concentration within the longissimus muscle tissue (P=0.05). Concentration of C18:3 increased with increased roughage inclusion rate. Fatty acid profiles for LM, IMF and SQ tissues were similar across treatments. There was not treatment effect for marbling distribution collected via Computer Vision System Ribeye Camera evaluation. Overall, the data suggests that roughage inclusion rate causes very little impact on feedlot performance, carcass characteristics, fatty acid composition and marbling distribution in Wagyu cattle. Advisors/Committee Members: Peel, Kraig (advisor), Archibeque, Shawn (committee member), Holt, Timothy (committee member).

▼ Fifteen steers were used to evaluate the difference of diets (corn-based for 8 mo or hay-based for 12 mo) and breeds (Angus; n = 7 or Wagyu; n = 8) in a completely randomized design with 2 x 2 factorial arrangement of treatments to test the hypothesis that there are differences in fatty acid metabolism and cellularity in subcutaneous (s.c.) and intramuscular (i.m.) adipose tissue between these breeds types. Fat thickness, carcass weight, overall maturity, and yield grade of Angus steers were higher than those of Wagyu steers fed either corn (34%, 22%, 3%, and 8% higher, respectively) or hay diets (20%, 8%, 10%, and 8% higher, respectively) (P < 0.03). Moreover, marbling scores tended (P = 0.70) to be greater in Angus steers than in Wagyu steers fed either diet. Lipogenesis from acetate in both s.c and i.m. adipose tissue was higher in Wagyu steers (212.82 and 86.23 nmol/(105 cells per 2 h)) than in the Angus steers (86.23 and 29.66 nmol/(105 cells per 2 h)). Also, acetate incorporation into fatty acids was greater in s.c. adipose tissue than in i.m. adipose tissue (P < 0.05). Subcutaneous adipose tissue stearoyl-CoA desaturase (SCD) activity was significantly greater in corn-fed steers and than in hay-fed steers (P < 0.05), but there was no difference in SCD activity between Angus and Wagyu steers (P > 0.05). Adipocyte cellularity data demonstrated that both breeds have more cells per gram adipose tissue and smaller cell volumes in i.m. adipose tissue than in s.c. adipose tissue. In s.c. adipose tissue, saturated fatty acids tended to be lower in corn-fed Angus and Wagyu steers than in hay-fed steers (P < 0.06). Similarly, monounsaturated fatty acids were higher in corn-fed Wagyu and Angus steers than in hay-fed Wagyu and Angus steers (P < 0.01). Slip point was positively correlated with percentage stearic acid in corn-fed and hay-fed steers, and there was a negative correlation between slip point and the SCD index. These data demonstrated that corn-based diets provide not only increased contents of monounsaturated fatty acid in Angus and Wagyu adipose tissue but also increased lipogenic activity. Advisors/Committee Members: Smith, Stephen B. (advisor), Cartwright, A. Lee (committee member), Lunt, David K. (committee member), Sawyer, Jason E. (committee member).

▼ The first study investigates implementing a crossbreeding strategy on Jersey dairy farms, where a terminal beef sire would be mated to a proportion of the herd to increase the value of the male offspring compared with purebred Jersey steers. In general, crossbred Jersey cattle, sired by Angus, SimAngus, and Red Wagyu bulls, had a greater ADG and lesser G:F compared with purebred Jersey steers. As a result of the lesser ADG of purebred Jersey steers, they required the greatest amount of time on feed. Crossbred Jersey cattle achieved greater final body weights with fewer days on feed. Purebred Jersey cattle had a lesser backfat thickness, but deposited a greater percentage of kidney fat compared with crossbred Jersey steers. Crossbred Jersey cattle had a greater marbling score and USDA quality grade compared with purebred Jersey steers. The USDA YG equation did a poor job of predicting carcass cutability of all Jersey influenced cattle in this study. Overall, crossbred Jersey cattle had a greater boxed beef price and boxed beef value compared with purebred Jersey steers. Sire selection criteria for Jersey crossbreeding programs should focus on retail yield and should consider the use of growth enhancing technologies to increase muscle deposition. The second study was designed to further investigate marbling development in cattle. Wagyu and Angus sired cattle were compared at a similar age and days spent on feed or at a similar body weight endpoint to compare feedlot performance, carcass composition, and the expression of marbling related genes. Two Wagyu sires were used in this study, one selected for growth (LMR Fukutsuru 729T) and the other selected for marbling ability (OW Yasufuku 229Y). When compared at a similar age and days spent on feed, Angus sired cattle had a greater ADG, DMI, G:F, and off-test weight compared with Yasufuku sired cattle, while Fukutsuru sired cattle were similar to Angus sired cattle, except for having a lesser DMI. Yasufuku sired cattle had a greater marbling score and USDA QG compared with Angus sired cattle. When compared at a similar off-test body weight, Angus sired cattle had a greater ADG, DMI, and G:F, spent fewer days on feed, were younger at harvest, and had a lesser total DMI over the course of the entire study. Yasufuku sired cattle had a greater marbling score, USDA QG, and 6th rib fat thickness compared with Angus sired and Fukutsuru sired cattle. At both endpoint comparisons, Yasufuku sired cattle had a longissimus muscle fatty acid composition that was more desirable compared with Angus sired cattle, while Fukutsuru sired cattle were typically intermediate. Gene expression results may indicate two critical periods of intramuscular adipogenesis initiation at approximately 7 and 17 months of age. The upregulation of lipogenic genes was initiated around 12 months of age and peaked at 14 months of age. The gene expression results of Yasufuku sired cattle exhibited random peaks that may be responsible for preadipocyte proliferation compared with Angus and Fukutsuru sired cattle. Advisors/Committee Members: Relling, Alejandro (Advisor), Fluharty, Francis (Advisor).

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Com o objetivo de caracterizar o crescimento de animais cruza Wagyu x Angus, 24 machos castrados e 23 fêmeas foram separados em: G1M (Grupo 1 Machos, com percentagem de gordura intramuscular inicial > 3,4%, n= 11), G2M (Grupo 2 Machos, com percentagem de gordura intramuscular inicial < 3,4%, n= 13), G1F (Grupo 1 Fêmeas, com percentagem de gordura intramuscular inicial > 3,9%, n= 12) e G2F (Grupo 2 Fêmeas, com percentagem de gordura intramuscular inicial < 3,9%, n= 11) e avaliados com medidas seriadas de ultrassom ajustadas a cada 56 dias. Para estimar as características de carcaça foram utilizados 21 machos castrados, avaliados por ultrassom 3 a 8 dias pré abate e posteriormente na carcaça com 48 horas de resfriamento. O grupo G2M apresentou maior deposição de gordura subcutânea por ultrassom (EGSUS) em seis períodos de avaliação quando comparado ao G1M, apresentando uma taxa de deposição de gordura subcutânea distinta entre grupos de 0.69mm/100 dias e 0.65mm/100 dias para o G2M e G1M, respectivamente. Somente foi possível evidenciar diferença significativa na primeira avaliação de percentagem de gordura intramuscular (PGIMUS) entre G1M e G2M, ambos apresentaram crescimento linear com taxa de aumento de 0.28%/100 dias, foi possível evidenciar que ocorreram aumentos acima de 0.1% da PGIMUS a partir dos 280 dias do período de avaliação, quando o ganho médio diário (GMD) de peso vivo ficou acima de 0.650 kg/dia. A taxa de desenvolvimento da área do músculo longissimus (AOLUS) foi distinta entre os grupos de fêmeas, aumentando 3.8 cm2/100 dias e 3.4 cm2/100 dias para o G1F e G2F, respectivamente. Ocorreram diferenças significativas na PGIMUS somente nas quatro primeiras avaliações entre G1F e G2F. A correlação entre a área do músculo longissimus medida na carcaça (AOLC) e por ultrassom (AOLUS) foi de 0.93, para espessura de gordura subcutânea medida na carcaça (EGSC) e por ultrassom (EGSUS) foi de 0.86. A PGIMUS a desmama não afetou o crescimento do tecido muscular nos machos e adiposo nas fêmeas. As características gordura subcutânea no sítio anatômico da costela nos machos e AOLUS nas fêmeas apresentaram crescimento distinto com relação à PGIMUS a desmama. A ultrassonografia é uma tecnologia que pode ser utilizada para estimar o desenvolvimento tecidual da gordura e músculo com medidas repetidas no tempo. O peso vivo e o GMD afetaram a alteração do tecido muscular e adiposo durante o crescimento.

Aiming to characterize the growth crossbred Wagyu x Angus, 24 steers and 23 heifers were separated in: G1M (Group 1 Males, with initial percentage of intramuscular fat > 3,4%, n= 11), G2M (Group 1 Males, with initial percentage of intramuscular fat < 3,4%, n= 13), G1F (Group 1 Females with initial percentage of intramuscular fat > 3,9%, n= 12) e G2F (Group 2 Females, with initial of intramuscular fat percentage < 3,9%, n= 11) and evaluated with serial ultrasound measurements fitted every 56 days. To estimate carcass traits were used 21 steers, assessed by ultrasound 3 to 8 days pre slaughter and afterwards in the carcass…

Advisors/Committee Members: Lobato, Jose Fernando Piva, Tarouco, Jaime Urdapilleta.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliou-se o efeito de diferentes períodos de maturação (1, 7, 14 dias) sobre a qualidade da carne de dois músculos (Longíssimus dorsi e Tríceps braquii) de bovinos cruzados, criados em confinamento no sistema “superprecoce”. Foram utilizados 40 bovinos machos não castrados, divididos em quatro cruzamentos, oriundos do acasalamento de fêmeas cruzadas ½ angus + ½ nelore e ½ simental + ½ nelore com touros das raças Angus e Wagyu. Os animais foram confinados em lotes de 4 animais por baia divididos por grupo genético. Após o abate e estabelecimento do rigor-mortis (24 horas) coletou-se amostras dos músculos Longíssimus dorsi e Tríceps braquii, que foram embalados a vácuo e submetidos à maturação (0, 7 e 14 dias). Foram avaliadas características qualitativas (capacidade de retenção de água, cor, pH, perdas de peso por cozimento e força de cisalhamento) e sensoriais (sabor, odor, suculência, fibrosidade, maciez, sabor de gordura e aceitação global). Utilizou-se um delineamento inteiramente casualizado em esquema fatorial 4 x 3 x 2 (4 cruzamentos x 3 períodos de maturação x 2 músculos) com 10 repetições. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste Tukey com 5% de significância. A maturação é eficiente na melhoria da maciez da carne dos animais avaliados. Os animais filhos de touro Wagyu apresentaram carne com sabor de gordura mais acentuado através da avaliação sensorial. O músculo Tríceps brachii foi considerado mais macio e mais suculento tanto na análise sensorial como nas análises físicas, contudo, o músculo Longíssimos dorsi apresentou maior aceitação global

We evaluated the effect of different periods of maturation aged (0, 7 and 14 days) on meat quality of two muscles (Longíssimus dorsi and Triceps braquii) of crossbred beef cattle, reared in confinement in the system “youngbulls”. We used 40 bulls divided into four crossbred from the mating of cows crossbred ½ Angus + ½ Nelore e ½ Simental + ½ Nelore with bulls Angus and Wagyu. The animals were confined in collective stalls 4 animals for pen divided by genetic groups. After slaughter and establishment of rigor mortis (24 hours) samples were collected from muscles Longíssimus dorsi e Triceps braquii, which were vacuum packed and submitted of maturation aged (0, 7 and 14 days). We evaluated quality characteristics (water-holding capacity, color, pH, weight loss for cooking and shear force) and sensory (flavor, scent, juiciness, fibrousness, softness, fat flavor and global acceptance). It was used a 4 x 3 x 2 factorial arrangement (4 crossbred x 3 maturation aged x 2 muscles) with 10 replicates. The dates submitted analysis of…

Advisors/Committee Members: Universidade Estadual Paulista (UNESP), Souza, Pedro Alves de [UNESP], Tullio, Rymer Ramiz [UNESP].