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Gijón, Spain

Cervantes I.,Complutense University of Madrid | Gutierrez J.P.,Complutense University of Madrid | Fernandez I.,SERIDA Somio | Goyache F.,SERIDA Somio
Journal of Animal Science | Year: 2010

The aim of this paper was to estimate the genetic relationships among calving ease (CE), calf survival (CS), and gestation length (GL) to assess the possibility of including this information in beef cattle breeding programs. A total of 35,395 field records were available for CE, 30,684 for GL, and 36,132 for CS from the Asturiana de los Valles beef cattle breed. The 3 traits were analyzed as traits of the calf fitting a multivariate linear mixed model. Estimates of heritability (±SE) for the direct genetic effects (CEd, GLd, and CSd) were 0.325 ± 0.022, 0.331 ± 0.026, and 0.226 ± 0.018, respectively, whereas the estimates for maternal genetic effects (CEm, GLm, and CSm) were 0.066 ± 0.018, 0.066 ± 0.017, and 0.034 ± 0.011. The estimates for the ratio of permanent environmental variance to phenotypic variance were CEc 0.090 ± 0.011, GLc 0.066 ± 0.011, and CSc 0.024 ± 0.007. Genetic correlations between direct, maternal genetic, or permanent environmental effects involving CE and GL were, in general, positive and moderate, whereas those involving CE and CS were high. All were significant except for the pair CEm-GLm (0.277 ± 0.172). Correlations between GL and CS were nonsignificant. Genetic correlations for CEd-CEm, GLd-GLm, and CSd-CSm were negative and high, ranging from -0.461 ± 0.120 for GLd-GLm to -0.821 ± 0.145 for CSd-CSm. The genetic correlations for CEd-CSm and for CSd-CEm were negative, significant, and high, whereas that for GLd-CEm was moderate (-0.323 ± 0.124) and that for GLd-CSm was nonsignificant. The genetic correlations for GLm with the direct effects of the other traits were non-significant. Strong selection for CE will result in a significant correlated response in CS. Therefore, CE can be considered an early indicator of CS performance. The benefit of using GL as a correlated trait in a genetic evaluation with CE and CS seems limited. © 2010 American Society of Animal Science. Source

Legaz E.,Castellana de Ganaderos Sociedad Cooperativa | Cervantes I.,Complutense University of Madrid | Perez-Cabal M.A.,Complutense University of Madrid | de la Fuente L.F.,University of Leon | And 3 more authors.
Small Ruminant Research | Year: 2011

Seventeen body measurements in a total of 341 adult individuals (61 males and 280 females) in addition to eight udder scores collected during the period of maximum levels of lactation in the 280 females were used to morphologically characterize the Assaf.E breed both in magnitude and variability. Sampling included the two main environmental areas to check if the native dairy sheep breeds, namely Churra and Manchega, leaded to differences in the male-mediated absorption. Standard morphology of the Assaf.E breed was assessed with a live weight of 110.47 ± 12.51. kg and 75.74 ± 11.23. kg respectively for males and females. The sexual dimorphism (m/f) was 1.13 as expected, with males being 46% heavier than females. The coefficient of variation of all traits ranged from 3.73% to 15.00%, showing high uniformity. Canonical analyses and Mahalanobis distances showed that differences in body measurements between regions existed but they were small as expected in a unique breed. The breed has shown itself to be slightly longer than others with deeper udders and more angled teat placement. Some peripheral traits such as ear and tail size, usually considered important in the breed definition, have been shown to have a low, or null, relationship with other morphological traits. Even when homogeneity is found in the breed, there are still some small differences found between geographical areas as a consequence of the short history of the breed in Spain. However, after a 30 year history in Spain, the homogeneity of the Assaf.E breed allows this population to be defined as an authentic breed. © 2011 Elsevier B.V. Source

Pun A.,Complutense University of Madrid | Goyache F.,SERIDA Somio | Cervantes I.,Complutense University of Madrid | Gutierrez J.P.,Complutense University of Madrid
Livestock Science | Year: 2012

A total of 15,645 records of birth weight (BrW), weaning weight (WW) and average daily gain (ADG) from 6055 cows belonging to 2121 different dam lines were analyzed to quantify the contribution of cytoplasmic line (l) effects to phenotypic variance of preweaning growth traits in a sample of Asturiana de los Valles beef cattle breed. Only dam lines with 2 or more cows having performance records in the database were used. Bayesian estimates were obtained fitting eight different univariate and multivariate models defined depending on the inclusion or not of the permanent maternal environment (c) and the l effects. Univariate models that included both the c and the l effects had the best fit with data (assessed by computing the logarithm of the conditional predictive ordinate; logCPO) for BrW and ADG while for WW this was the case for the model that only included the c effect. For multivariate models, the best fit with data was obtained for the model that only included the c effect (logCPO=-245,899) while the second "better" model was that which only include the l effect value (logCPO=-241,108). In general, whatever the estimation model used, estimates of heritability for the direct (h2) and maternal (m2) genetic effects and the genetic correlation between them (ram) obtained in the current study for BrW were slightly higher (ram more negative) than the most recent estimates reported in the breed. However, this is not true for WW and ADG when multivariate estimation models include the l effect. In these cases, estimates of h2 and m2 for WW and ADG tend to be lower and ram less negative than those previously estimated. In conclusion, the cytoplasmic line may have a marginal effect on growth performance in beef cattle but not sufficient in magnitude to justify including the l effect in models in beef improvement schemes. © 2011 Elsevier B.V. Source

Perez-Cabal M.A.,Complutense University of Madrid | Legaz E.,Castellana de Ganaderos Sociedad Cooperativa | Cervantes I.,Complutense University of Madrid | De La Fuente L.F.,University of Leon | And 3 more authors.
Archiv Tierzucht | Year: 2013

The relationship between 17 body and 8 udder measurements and phenotypic dairy performance were studied using information from 280 Spanish Assaf ewes from 2 to 4 years old belonging to 18 flocks. The influence of the environmental area on the dairy traits was assessed by fitting a fixed model including the flock effect and the age effect. A factor analysis was also carried out to determine the lowest number of independent factors that account for most of the variation in the traits. The flock was statistically significant for performance trait and predicted breeding value (PBV) while the age was only significant in 150 days standardized milk yield (MY150) and daily milk yield (DMY). In general, not much association was found between morphological and dairy performance traits. Few body traits showed significant phenotypic correlations; mainly those related to height, diameters, ears and tail, with the latter being the most correlated but unfavourable for DMY and PBV. Among udder conformation, udder depth and length were the most correlated traits to milk production, while deep udders and short teats were related to lower somatic cell counts. The different traits were classified for analyses into six factors relating mainly to: live weight; production and udder traits; cheese production; stature; teats and udder health; and udder dimensions. Trade of animals was concluded to be unreasonably based on morphological or even on performance traits. The participation of breeders in an appropriate breeding scheme based on accurate genetic evaluations is encouraged. © 2013 by the authors. Source

Cervantes I.,Complutense University of Madrid | Perez-Cabal M.A.,Complutense University of Madrid | Morante R.,Pacomarca S.A. | Burgos A.,Pacomarca S.A. | And 4 more authors.
Small Ruminant Research | Year: 2010

Four fibre traits (fibre diameter, FD; coefficient of variation of FD, comfort factor; and standard deviation of FD) were jointly analysed with six subjectively scored type traits (fleece density, crimp, lock structure, head, coverage, and balance) in two breeds of Peruvian Altiplano alpaca (Suri, SU; and Huacayo, HU) to ascertain their genetic relationship. A total of 2405 fibre records and 2194 type scores were available for the HU breed whereas these figures were 709 for fibre records and 650 for type scores for the SU breed. Estimated heritabilities for fibre traits were moderate to high, ranging from 0.565 to 0.699 in the SU breed and from 0.255 to 0.417 in the HU breed. Genetic and permanent environmental correlations between fibre related traits were extremely similar across breeds suggesting that these traits are fairly the same. Heritabilities estimated for the type traits tended to be lower than those estimated for the fibre traits particularly in the SU breed (ranging from 0.173 to 0.272). Fibre and type traits were, in general, genetically poorly correlated except for crimp in the HU breed, which had favourable correlations, from moderate to high, for fibre traits. In Altiplano areas in which fibre performance recording could not be implemented, crimp scoring makes it feasible to carry out mass selection in the Huacayo breed and furthermore include rural communities in national or regional selection programmes. © 2009 Elsevier B.V. All rights reserved. Source

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