Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1959. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 337-353).

Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains viii, 137 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 93-103).

Thesis (Ph. D.)--Washington State University, May 2006. / Includes bibliographical references.

Thesis (MS)--Montana State University--Bozeman, 2010. / Typescript. Chairperson, Graduate Committee: John Paterson. Includes bibliographical references (leaves 44-50).

Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.

Made available in DSpace on 2014-06-11T19:26:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-06Bitstream added on 2014-06-13T18:54:03Z : No. of bitstreams: 1 menezes_lm_me_jabo.pdf: 354341 bytes, checksum: fe80f7c1719a7e65ac618ed0d97b9df5 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este estudo teve como objetivo avaliar as relações entre o temperamento e características de escores visuais. Utilizou-se a estatística bayesiana, com análises tricaracterísticas sob modelo animal linear-limiar na obtenção dos parâmetros genéticos e estimação de coeficientes de correlação genética, sendo o seguinte modelo utilizado: y = Xβ + Z1a + Z2m + Z3c + e. Foram avaliadas as características: conformação (CS), precocidade (PS), musculatura (MS), escore de temperamento (ET) e velocidade de saída (VS), avaliadas ao sobreano, além do peso ao desmame (PD), como característica “âncora”. Para as características CS, PS e MS os maiores escores indicaram as melhores expressões das características. Para o ET os maiores escores indicaram animais de pior temperamento e para VS os maiores valores indicaram os animais de melhor temperamento. Foram utilizados dados de animais da raça Nelore, com 125.760 animais na matriz de parentesco, nascidos entre 1984 e 2010, pertencentes à Agropecuária Jacarezinho Ltda. As herdabilidades estimadas para ET, VS, CS, PS e MS foram 0,25 ± 0,01; 0,21 ± 0,01; 0,32 ± 0,03; 0,34 ± 0,04 e 0,31 ± 0,03, respectivamente. As correlações genéticas entre temperamento e escores visuais foram favoráveis, entretanto baixas: ET x CS= -0,13 ± 0,01; ET x PS = -0,10 ± 0,02 e ET x MS = -0,17 ± 0,02; VS x CS = -0,09 ± 0,00; VS x PS = -0,14 ± 0,22 e VS x MS = - 0,14 ± 0,01. Não recomenda-se a seleção indireta para temperamento através da seleção para os escores visuais de CS, PS ou MS. A inclusão de temperamento (ET ou VS) e CS, PS e MS, simultaneamente nos índices de seleção, pode ser realizada, com a expectativa de mudanças a longo prazo / This study aims to evaluate the relationship between temperament and visual scores traits. Bayesian statistics was used, with tri-characteristic analysis under the linear-treshold animal model to obtain the genetic parameters and the estimation of coefficients of genetic correlation, according to the following model: y = Xβ + Z1a + Z2m + Z3c + e. The following characteristics were considered: conformation (CS), precocity (PS), muscularity (MS), temperament score (ET) and flight speed (VS), evaluated at the yearling, besides the weaning weight (PD), as an “anchor” trait. For CS, PS and MS the greatest scores indicate the best expressions of characteristics. For the ET the highest score indicate animals with the worst temperament and for VS the highest values indicate animals with the best temperament. Data from 125.760 Nelore cattle in the kinship matrix, born between 1984 and 2010, belonging to the Agropecuária Jacarezinho Ltda. were used for the analysis. The estimated heritability for ET, VS, CS, PS and MS were 0,25 ± 0,01; 0,21 ± 0,01; 0,32 ± 0,03; 0,34 ± 0,04 e 0,31 ± 0,03, respectively. The genetic correlations between temperament and visual scores were favorables, but low: ET x CS= -0,13 ± 0,01; ET x PS = -0,10 ± 0,02 e ET x MS = -0,17 ± 0,02; VS x CS = -0,09 ± 0,00; VS x PS = -0,14 ± 0,22 e VS x MS = -0,14 ± 0,01. It is not recommended to apply indirect selection for temperament through the selection for the visual scores of CS, PS or MS. The inclusion of temperament (ET or VS) and CS, PS and MS, simultaneously in the selection indices, may be performed, with the expectation of long-term effects

Master of Science / Department of Animal Sciences and Industry / Robert L. Weaber / Feet and leg soundness is an important trait for beef producers as it has an impact on cow longevity and animal well-being. The objective of this study was to investigate genetic parameter estimates for feet and leg traits, understand the relationship between feet and leg traits and Stayability EPD, and develop a scoring method for feet and leg traits in Red Angus cattle. Cattle were scored on 14 subjective traits: Body Condition Score (BCS), Front Hoof Angle (FA), Front Heel Depth (FHD), Front Hoof Claw Shape (FC), Rear Hoof Angle (RA), Rear Heel Depth (RHD), Rear Hoof Claw Shape (RC), Foot Size (FS), Hoof Orientation (HO), Knee Orientation (KO), Front Side View (FSV), Rear Leg Side View (RS), Rear Leg Hind View (RH), Composite Score (CS). Red Angus cattle (n=1885) were scored for all 14 traits by trained evaluators. All traits except CS were scored with the assumed optimum level being in the middle with undesirable scores being located on the extremes. Scores were observed on a scale of 1-100 and analyzed, then scores were simplified to 1-9 where scores were collapsed by 10’s into bins, starting at 10 since there were no scores observed below that point and the rubric used did not have an associated phenotype below that point. A three-generation pedigree file was obtained from the Red Angus Association of America (RAAA) that contained 13,306 animals, as well as a performance file on all animals observed in the study. Data were modeled using multiple linear bivariate animal models with additive and residual random effects, and age and contemporary group (herd-year) as fixed effects. Genetic parameters were estimated with ASREML4.0. Heritability estimates on the 1-9 scale for BCS, FA, FHD, FC, RA, RHD, RC, FS, HO, KO, FSV, RS, RH, and CS were 0.13, 0.18, 0.12, 0.08, 0.17, 0.24, 0.15, 0.29, 0.15, 0.15, 0.11, 0.29, 0.11, and 0.09 respectively. In general, feet and leg traits were lowly to moderately heritable, and are similar when compared to estimates for the same traits scored on a 1-100 scale. This informs a less granular and more simplified scale of measurement can be an appropriate method of feet and leg trait classification. Front hoof angle, FHD, RA, and RHD were all highly genetically correlated (r = 0.83 - 0.97), suggesting that angle and heel depth are controlled by many of the same genes. Front claw shape and RC were highly genetically correlated (r = 0.80) with each other but were not as significantly correlated with FA, FHD, RA, RHD (r = -0.43 to 0.38). This suggests that hoof angle/depth should be measured separately from claw shape. Rear leg side view, and RH had a strong correlation (r = 0.69). Strong correlations between FSV, HO, and KO also existed, yet there was noticeable variation among point estimates and standard error. Six traits on the 1-9 scale were selected to generate estimated breeding values (EBV’s) based on their heritability and correlation with other traits; BCS RHD, RC, FS, RSV, RH. A linear model was used to determine breeding values for BCS, RHD, RC, FS, FSV and RH. Those breeding values were regressed on Stayability EPD. When fixed effects of herd, age and year born were accounted for, RC (P < 0.0001), RSV (P = 0.0517), and FS (P = 0.086) had relationships as predictor variables for Stayability EPD. The use of feet and leg traits as predictor variables for improved Stayability EPD can be achieved with a simplified scoring system (1-9 vs. 1-100) in Red Angus cattle. By narrowing the number of traits needed to measure with a more simplified scoring method should allow for more rapid adoption among current beef cattle producers. A greater number of observations could be useful to validate these results and provide more accurate point estimates for feet and leg trait heritabilities and correlations.

Master of Science / Department of Animal Sciences and Industry / Jennifer M. Bormann / Robert L. Weaber / The objective of this study was to investigate the parameter estimates for feet and leg traits, relationships within feet and leg traits, and between feet and leg traits and production traits in Red Angus cattle. Subjective scores for 14 traits including: Body Condition Score (BCS), Front Hoof Angle (FHA), Front Heel Depth (FHD), Front Claw Shape (FCS), Rear Hoof Angle (RHA), Rear Heel Depth (RHD), Rear Claw Shape (RCS), Size of Hoof (Size), Front Side View (FSV), Knee Orientation (KNEE), Front Hoof Orientation (FHO), Rear Side View (RSV), Rear View (RV), and a Composite Score (COMP) were collected by trained evaluators on 1885 Red Angus cattle at different ranches across the United States. A three-generation pedigree file was obtained from the Red Angus Association of America (RAAA) that contained 13,306 animals, and EPDs on all animals with feet and leg scores were obtained. All traits except COMP were scored as intermediate optimum traits. Data were modeled using a linear bivariate animal model with random additive genetic and residual effects, and fixed effects of age and contemporary group (herd-year). Variances were estimated with ASREML 3.0 and 4.0. Heritability estimates of BCS, FHA, FHD, FCS, RHA, RHD, RCS, Size, FSV, Knee, FHO, RSV, RV, and COMP were 0.11, 0.20, 0.17, 0.09, 0.19, 0.25, 0.17, 0.36, 0.16, 0.17, 0.17, 0.30, 0.14, and 0.12, respectively. These results showed feet and leg traits were lowly to moderately heritable. Strong, positive genetic correlations were found between FHA and FHD (0.89), FHA and RHA (0.88), FHD and RHA (0.85), FHA and RHD (0.85), FHD and RHD (0.94), and FHO and Knee (0.95), indicating these traits may be highly related to one another. Strong negative correlations were found between Knee and FSV (-0.59) and FHO and FSV (-0.75). The strongest correlation was between front limb traits (FHA, FHD, FSV, FHO, Knee, and Comp) and the Stayability EPD (STAY) was FSV (r =0.16; r_s =0.20) and for rear limb traits (RHA, RHD, RCS, RSV, RV, and Comp) and STAY was RCS (r = -0.12; r_s=-0.14). This indicates that cattle with more slope to the angle of the shoulder stay in the herd longer and cattle with less curl to the inside of the claw tend to stay in the herd longer. Further studies with more data could help validate the relationship between feet and leg traits and production traits.