999 resultados para young bull
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Genetic correlations of young bull and heifer puberty traits with measures of early and lifetime female reproductive performance were estimated in two tropical beef cattle genotypes. Heifer age at puberty was highly (r(g) = -0.71 +/- 0.11) and moderately (r(g) = -0.40 +/- 0.20) genetically correlated with pregnancy rate at first annual mating (mating 1) and lifetime annual calving rate, respectively in Brahman (BRAH). In Tropical Composite (TCOMP), heifer age at puberty was highly correlated with reproductive outcomes from the first re-breed (mating 2), mainly due to its association with lactation anoestrous interval (r(g) = 0.72 +/- 0.17). Scrotal circumference were correlated with heifer age at puberty (r(g) = -0.41 +/- 0.11 at 12 months in BRAH; -0.30 +/- 0.13 at 6 months in TCOMP) but correlations were lower with later female reproduction traits. Bull insulin-like growth factor-I was correlated with heifer age at puberty (r(g) = -0.56 +/- 0.11 in BRAH; -0.43 +/- 0.11 in TCOMP) and blood luteinising hormone concentration was moderately correlated with lactation anoestrous interval (r(g) = 0.59 +/- 0.23) in TCOMP. Semen quality traits, including mass activity, motility and percent normal sperm were genetically correlated with lactation anoestrus and female lifetime female reproductive traits in both genotypes, but the magnitudes of the relationships differed with bull age at measurement. Preputial eversion and sheath scores were genetically associated with lifetime calving and weaning rates in both genotypes. Several of the early-in-life male and female measures examined were moderately to highly genetically correlated with early and lifetime female reproduction traits and may be useful as indirect selection criteria for improving female reproduction in tropical breeds in northern Australia.
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The feedlot performance of 30 post-weaning 3/4 Canchim 1/4 Nellore calves, with seven months of age and 208,8 kg of liveweight, was evaluated. Three different protein sources in isocaloric and isonitrogenous diets with 60:40 forage: concentrate ratio were used. The diets, fed ad libitum, constituted of corn silage, corn grain, mineral mix and a different protein source for each treatment: cottonseed meal, soybean meal and whole soybean. The weight gain, feed: gain ratio, dry matter and crude protein intake were evaluated for the growing (84 days) and fattening phases (84 days) and for the overall period. An economic study of young bulls production model was realized at the end of experimental period. Soybean meal based diet presented the best animal performance and provided R$ 51.30/head of net profit - the best economic result.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Bovine congenital pseudomyotonia (PMT) is a genetic disease in Chianina and other breeds of cattle that induces muscular stiffness. PMT in the Chianina breed is caused by a missense mutation in exon 6 of the ATP2A1 gene, which encodes the SERCA1 pump. In this study, the prevalence of PMT carriers and the frequency of the deleterious PMT allele in selected subpopulations of the Chianina breed were estimated. The prevalence of PMT carriers among ranked Chianina sires used for artificial insemination in the years 2007-2011 was 13.6%. The frequency of PMT carriers in young bull calves born in the period January 2007 to June 2011 selected for a performance testing programme was 13.4%. Selective breeding against this genetic defect is restricted to males only and therefore is predicted to require at least seven generations to eradicate PMT.
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The term 'paunch calf syndrome' encompasses the multi-organic lethal developmental dysplasia reported in the Romagnola breed of cattle and is characterised by facial deformities, an enlarged and floating abdomen containing considerable abdominal effusion, and hepatic fibrosis. Paunch calf syndrome is caused by a missense mutation in the KDM2B gene (c.2503G>A) that is thought to lead to an amino acid exchange (p.D835N). In this study, the prevalence of carriers of the mutant KDM2B allele (and thus the frequency of the allele) was assessed in selected subpopulations of Romagnola cattle. The prevalence of carriers within top-ranked Romagnola sires over the years 2007-2012 was 29.3% (allele frequency 14.6%). In young bull calves, 30.9% were carriers with an allele frequency of 15.4%.
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A total of 4063 young bulls of two tropical genotypes (1639 Brahman and 2424 Tropical Composite) raised in northern Australia were evaluated for a comprehensive range of production and reproduction traits up to 24 months of age. Prior to weaning, peripheral blood concentrations of luteinising hormone (LH) and inhibin were measured at 4 months of age. At weaning (6 months) blood insulin-like growth factor-1 (IGF-I) and flight time were recorded. Body composition traits of fat depth and eye-muscle area were determined by ultrasonography at 15 months of age when additional measurements of liveweight, hip height and body condition score were recorded. Bull breeding soundness was evaluated at similar to 12, 18 and 24 months of age when measurements of scrotal circumference, sheath score, semen mass activity, progressive motility of individual sperm and percent morphologically normal sperm were recorded. Magnitude of heritability and genetic correlations changed across time for some traits. Heritability of LH, inhibin, IGF-I and of 18-month scrotal circumference, mass activity, progressive motility and percent normal sperm was 0.31, 0.74, 0.44, 0.75, 0.24, 0.15 and 0.25, respectively, for Brahmans and 0.48, 0.72, 0.36, 0.43, 0.13, 0.15 and 0.20, respectively, for Tropical Composites. Inhibin and IGF-I had moderate genetic association with percent normal sperm at 24 months in Brahmans but low to negligible associations in Tropical Composites. Body condition score in Brahmans and sperm motility (mass and individual) traits in both genotypes had moderate to strong genetic correlation with percent normal sperm and may prove useful candidates for indirect selection. There is scope to increase scrotal circumference by selection and this will be associated with favourable correlated responses of improved semen quality in both genotypes. The lack of genetic antagonism among bull traits indicates that selection for improved semen quality will not adversely affect other production traits.
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Sperm chromatin fragmentation is associated with subfertility, but its relationship with age progression in young bulls is poorly understood. The objective was to assess sperm chromatin fragmentation during the early post-pubertal development of 20 tropical composite bulls, using a sperm chromatin structure assay (SCSA) and sperm-bos-halomax (SBH). Bulls were subjected to bull breeding soundness evaluation (BBSE) at mean ages of 13, 18, and 24 mo. Traits measured included liveweight (WT), body condition score (BCS) and scrotal circumference (SC). Semen samples were collected by electroejaculation and assessed for mass activity (MA), motility (Mot), concentration (conc), sperm morphology and chromatin fragmentation. Concentration (r = 0.34, P = 0.0076), Mot (r = 0.36, P = 0.0041) and percentage of morphologic normal sperm (percent normal sperm (PNS); r = 0.31, P = 0.0132) were positively correlated with age. The percentage of sperm with proximal droplets (PD) was negatively correlated with age (r = -0.28, P = 0.0348), whereas neither SCSA nor SBH results were significantly correlated with age. The percentage of sperm with chromatin fragmentation using SCSA was correlated with PNS (r = -0.53, P < 0.0001), the percentage of sperm with head abnormalities (r = 0.68, P < 0.0001) and the percentage of intact sperm (Int) with SBH (r = -0.26, P = 0.0456). In summary, for assessment of sperm chromatin fragmentation, samples could be equally collected at 13, 18 or 24 mo of age, as results did not vary with age. (c) 2012 Elsevier Inc. All rights reserved.
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O desenvolvimento de técnicas não invasivas e não destrutivas para a avaliação da composição e qualidade de carcaça em animais tem mobilizado consideráveis recursos em pesquisa. A ultra-sonografia aparece neste contexto como uma técnica viável, confiável e de custo aceitável para esta função. No presente trabalho foi avaliada a técnica de ultra-sonografia em tempo real como ferramenta para predição da área de olho-de-lombo (AOL) e espessura da camada de gordura subcutânea (ECG) a partir de imagens tomadas em animais vivos, quando comparadas com as medições na carcaça. Foram utilizados 115 bovinos jovens (30, ½ Angus x Nellore; 30, ½ Canchim x Nellore; 30, ½ Simental x Nellore, e 25 Nellores), com peso inicial médio de 329 kg e de dois tamanhos à maturidade (pequeno e grande), no sistema de produção do novilho superprecoce. As medidas de ultra-sonografia foram realizadas a cada 28 dias totalizando quatro medições até o final do confinamento. A precisão da predição aumentou em função da proximidade da data do abate, sendo máxima na quarta medida (R²= 0,68 para AOL e 0,82 para ECG). Houve efeito de grupo genético e de medida ultra-sonográfica para ECG. O tamanho corporal não teve efeito sobre nenhuma das características estudadas.
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Lymphoma is the most prevalent neoplasia in dairy cattle. The etiology can be viral in animals affected by bovine leukemia virus (BLV) or be classified as primary. Lymphoma can affect several organs and according to the system involved, the clinical signs could manifest themselves in different ways. These tumors can be classified through macroscopic characteristics, histology and immunostaining. This classification can be used to predict prognosis and response to therapy. The aim of this case report was to immunostain and classify the tumor, for which anti-CD4, anti-CD8, anti-CD79 and anti-CD3 markers were used in addition to histopathological findings, in order to classify the tumor. The tumor was positive only for anti-CD3 marker, indicating that it is a tumor of young cells and, in association with histopathology and hematological data, it can be concluded that spleen neoplasia is lymphocytic lymphoma originated from a lymphocytic leukemia.
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The degree of reliance of newborn sharks on energy reserves from maternal resource allocation and the timescales over which these animals develop foraging skills are critical factors towards understanding the ecological role of top predators in marine ecosystems. We used muscle tissue stable carbon isotopic composition and fatty acid analysis of bull sharks Carcharhinus leucas to investigate early-life feeding ecology in conjunction with maternal resource dependency. Values of δ13C of some young-of-the-year sharks were highly enriched, reflecting inputs from the marine-based diet and foraging locations of their mothers. This group of sharks also contained high levels of the 20:3ω9 fatty acid, which accumulates during periods of essential fatty acid deficiency, suggesting inadequate or undeveloped foraging skills and possible reliance on maternal provisioning. A loss of maternal signal in δ13C values occurred at a length of approximately 100 cm, with muscle tissue δ13C values reflecting a transition from more freshwater/estuarine-based diets to marine-based diets with increasing length. Similarly, fatty acids from sharks >100 cm indicated no signs of essential fatty acid deficiency, implying adequate foraging. By combining stable carbon isotopes and fatty acids, our results provided important constraints on the timing of the loss of maternal isotopic signal and the development of foraging skills in relation to shark size and imply that molecular markers such as fatty acids are useful for the determination of maternal resource dependency.
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Introducción: En la presente investigación nos vamos a centrar en los contenidos on line que ofrece la marca Red Bull ya sea a través de su web www.redbull.tv o de su App Red Bull TV. Red Bull como marca necesita destacar de entre todo el ruido publicitario, necesita hacerse notar y llegar hasta sus consumidores, pero hoy en día las audiencias están fragmentadas, las audiencias no están sometidas al dictado programático de las televisiones. Cada vez más, y sobre todo en el público joven, que es aquel con el que más se identifica esta marca, es un público activo que genera sus propias parrillas de programación, que busca aquello que realmente quiere ver. Entonces, ¿cómo una marca logra que se le escuche? a través del Rock&Love: sorprender y dar amor. Hipótesis: Nuestra hipótesis de partida es que Red Bull, en la búsqueda de conexión con su público, les ofrece contenidos de su interés que les reafirma en su acercamiento a la marca, y así lograr el Rock&Love. Objetivos: De acuerdo con la hipótesis, son tres los objetivos que van a guiar la presente investigación: el primero, conocer las claves de Red Bull en el entorno digital. El segundo, realizar un análisis de los contenidos utilizados por la marca para aproximarse a sus usuarios teniendo en cuenta los nuevos hábitos de consumo. El tercero, analizar la diferencia de contenidos según el medio en que se difunde. Metodología: Para corroborar o no nuestra hipótesis participaremos del método cualitativo y del método cuantitativo. Las técnicas a utilizar son la observación documental y el análisis de contenido. Conclusiones: Este análisis de contenido Ad Hoc ha permitido la obtención de datos cuantitativos y nos ha facilitado la aproximación a nuestros objetivos de forma cualitativa y de esta forma, se ha logrado dar respuesta a la hipótesis de partida y confirmar que la marca recurre al Rock&Love en los contenidos que muestran a través de las diferentes plataformas de Red Bull TV.
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Introduction: Adolescence is a stage of life cycle marked by various physical, psychological and social changes. During this stage, young people are faced with the feeling of threat of identity, which may trigger aggressive behaviours. Bullying is a form of school violence with high prevalence, that shouldn't be a "normal" occurrence or a event that young people should experience during the transition between childhood and adolescent. In order to reduce the prevalence of bullying in the school community, we elaborated the Educational Intervention Project "R.E.D. BULL(ying)", with the specific objectives: Evaluate the knowledge level about bullyng, before and after the Project, and increase the level of literacy about the subject in the school community (students and teachers). Methodology: Our target population consisted in a total of 203 students from 5th to 9th grade and 13 teachers of school. It's a cross-sectional study of research - action, with the application of a diagnostic questionnaire, before and after, we conducted the educational sessions. Results: After the educational sessions, 93,1% of students identified what to do in a bullying situation, and 62,6% of students responded that in an assault situation, called an adult; 95,1% said they knew what was bullying, 56,8% associated the concept to physical aggression and 92,6 % mentioned to know the types of bullying, and physical bullying (71,9%) and verbal bullying (69,5%) were the most mentioned types. Meanwhile, the teachers: 76,9% considered that the school environment was pleasant, 84,6% characterized the relationship between the students as "adequate" and 77% said they didn't experience any bullying situation. Conclusions: We found an overall improvement to the level of bullying related knowledge after the educational intervention. So, we verified that the integrated intervention in the school health teams, allows greater attention to the detection, signalling and routing situations of violence.
Resumo:
Introduction: Adolescence is a stage of life cycle marked by various physical, psychological and social changes. During this stage, young people are faced with the feeling of threat of identity, which may trigger aggressive behaviours. Bullying is a form of school violence with high prevalence, that shouldn't be a "normal" occurrence or a event that young people should experience during the transition between childhood and adolescent. In order to reduce the prevalence of bullying in the school community, we elaborated the Educational Intervention Project "R.E.D. BULL(ying)", with the specific objectives: Evaluate the knowledge level about bullyng, before and after the Project, and increase the level of literacy about the subject in the school community (students and teachers). Methodology: Our target population consisted in a total of 203 students from 5th to 9th grade and 13 teachers of school. It's a cross-sectional study of research - action, with the application of a diagnostic questionnaire, before and after, we conducted the educational sessions. Results: After the educational sessions, 93,1% of students identified what to do in a bullying situation, and 62,6% of students responded that in an assault situation, called an adult; 95,1% said they knew what was bullying, 56,8% associated the concept to physical aggression and 92,6 % mentioned to know the types of bullying, and physical bullying (71,9%) and verbal bullying (69,5%) were the most mentioned types. Meanwhile, the teachers: 76,9% considered that the school environment was pleasant, 84,6% characterized the relationship between the students as "adequate" and 77% said they didn't experience any bullying situation. Conclusions: We found an overall improvement to the level of bullying related knowledge after the educational intervention. So, we verified that the integrated intervention in the school health teams, allows greater attention to the detection, signalling and routing situations of violence.