José M. León

Analysis of the Non-Genetic Factors Affecting the Growth of Segureño Sheep

A study was conducted to evaluate the effects of non-genetic factors on the growth behaviour of Segureña sheep breed. Growth related data (early weaning weight, late weaning weight and weight at 80 days of age) were taken from 59,704 lambs belonging to historical data from National Association of Segureño Sheep Breeders (ANCOS) during a period of 11 years. Statistical analyses were performed by using the multifactorial analysis of variance of IBM SPSS Statistics v.19 software. The model included non-genetic factors – lamb sex (S), birth season (N), herd (H), birth year (A) and birth type (P) – as main effects, the dam’s age at lambing and the lamb’s age when weighed as covariables, and the interactions between these factors. Results showed that all weights at developmental stages were significantly (P<0.001) affected by all factors, except for A and the covariable age of dams at lambing on lambs aged 80 days. Double interactions H×A, H×P and H×N were significant (P<0.001) for all variables, as well as the triple interaction H×A×P. Non-genetic factors have a very important role in the development and growth of the Segureña sheep breed, at different ages or growth stages, therefore a correction is necessary to increase the accuracy of direct selection on lamb weight at early weaning, late weaning and at slaughtering (80 days of age).

Advances in the breeding program of the Murciano-Granadina dairy goat breed

Abstract Murciano-Granadina is the most important dairy goat breed of Spain with more than 500,000 milking females. In the seventies an administrative decision admixture two of the most traditional Spanish breeds in a single herd book. Molecular studies demonstrated the existence of both original and a new admixture population. Our recommendation is to modify the Breeding program to a multibreed design enclosing multibreed Genetic evaluation. By now the Breeding program is under progress working with a productive information of 43,510 lactations standardized at 240 days length, belonging to 16,746 does (mean of 2.53 lactation/doe) located in 140 herds. The pedigree information disposable is about 19,563 individuals. 7,651 are founders; 804 sires; 7,642 dams; 559 grandsires and 2,907 grandmothers. With this information we evaluated genetically all the animals enclosed in the pedigree matrix. We got precision values (Rap) with picks of 0.98, for kg. of milk, fat and protein. The Genetic parameters have shown values for heritability and repeatability of 0.14-0.30 respectively for milk pro-duction; 0.18-0.26 for fat production and 0.17-0.29 for protein production, respectively. We have used the MTDFREML package to analyze the data by mean of a single trait animal model enclosing repeated observations, and multitraits models only to obtain the Genetic correlations. The additive Genetic effect and the permanent environment were considered random and Herd-Year-Season were considered fixed together with the age of the doe, introduced as linear and quadratic regression. The Genetic correlation shown values between 0.96 and 0.97 for all the combinations. These data are in the rang of the specie. This breed has shown its capacity inside and outside Spain, so the commercialization of Genetic products could be a new input for the future.

Murciano-Granadina Goat: A Spanish Local Breed Ready for the Challenges of the Twenty-First Century

The present chapter describes all the initiatives, ready or in progress, which have been and/or are being implemented to ensure the competitiveness of the Murciano-Granadina goat breed, so as to maintain its leadership in Spain, as the most representative dairy goat breed of the country at a national and an international level. After an intense introduction concerning the history and the present status of the breed, we started with the description of the presently ongoing official breeding program. Selection objectives and their associated criteria are presented together with a summary of the information used in the last genetic evaluation. This information is accompanied by the genetic parameters of the main selection criteria, i.e., milk production and content (fat, protein, and usable dry matter), and morphology, (through official milk yield control and linear morphological qualification, respectively) and an evaluation of the genetic response selection over 15 years of experience. In a different section, we present the results on the meat productivity with the aim to characterize all the process of meat production of the breed. Kid performance (daily gains, commercial weight, carcass characteristics, and quality) is defined under intensive, semi-intensive, and extensive management systems. A special interest is paid to the fatty acid profile of the meat from each tested management system. We conclude the chapter describing the future ongoing challenges to maintain the efficiency of the breed. On the one hand, we describe the study of lactation curve parameters, especially peak and persistence, as candidates for the selection criteria of the breed with the intention to increase the maximum production and its maintenance in an enlarged lactation. On the other hand, we described our dedication to develop the improvement of the case in profiles by using marker-assisted selection.

Efecto del semental sobre las características seminales del Caballo de las Retuertas

Resumen es: La concentracion geografica y el reducido censo del Caballo de las Retuertas obligaron a disenar un plan de conservacion integral. Una de las herramienta...