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Transmission ratio distortion (TRD) is the departure from the expected Mendelian ratio in offspring, a poorly investigated biological phenomenon in livestock species. Given the current availability of specific parametric methods for the analysis of segregation data, this study focused on the screening of TRD in 602 402 single nucleotide polymorphisms covering all autosomal chromosomes in seven Spanish beef cattle breeds. On average, 0.13% (n = 786) and 0.01% (n = 29) of genetic markers evidenced sire- or dam-specific TRD respectively. There were no single nucleotide polymorphisms accounting for both sire- and dam-specific TRD at the same time, and only one marker (rs43147474) accounted for (sire-specific) TRD in all seven breeds. It must be noted that rs43147474 is located in the fourth intronic region of the GTP-binding protein 10 gene, and this locus has been previously linked to the maintenance of mitochondria and nucleolar architectures. Alternatively, other candidate genes surround this hot-spot for sire-specific TRD in the cattle genome, and they are related to embryonic and postnatal lethality as well as prostate cancer, among others. This research characterized the distribution of TRD in the bovine genome, highlighting heterogeneous results when comparing across breeds.

The Ripollesa sheep breed is an important Spanish local breed mainly located in the Mediterranean mountains and cultivated plains of Catalonia, exploited under semi-extensive production systems and currently intended for meat production. The morphological characterization of the Ripollesa breed was carried out from the study of eight flocks representative of different subpopulations. A total of 224 Ripollesa ewes and 17 rams were recorded for their live weight and 12 morphological measures, which were used for calculating 12 zootechnical indexes. Differences (P < 0.05) between flocks and sexes were revealed for several measures. A principal component analysis was performed on the morphological measures and revealed two main principal components accounting for 47.6 and 12.3 percent of the inertia, being related to the frame (body size and live weight) and to withers height and ear length, respectively. The cluster analysis allowed differentiating among four subpopulations with relevant implications to be taken into account for the breed conservation programme. The observed differences could be attributable to geographic location, selective history, flock management and genetics. The estimated zootechnical indexes classified the Ripollesa sheep breed as a medium-sized and long-shaped body frame, with a marked orientation to meat production and with signs of adaptation to the environment.

The dietary composition of the semiferal cattle population in the Alberes Natural Park in northeastern Spain was determined four times per year, from June 2002 to February 2004, by microhistological analysis of a total of 120 fecal samples. Woody species, mainly the Quercus and Erica genera, formed the bulk of the diet, reaching 89% of it in winter. However, in spring and summer, the proportion of woody and herbaceous species varied between samples, depending on the habitat where they were collected. The forest samples contained 67% woody species in summer, whereas grassland samples only contained 44%. The results showed that the Alberes cattle population grazed actively in Mediterranean forests and consumed a high proportion of the most combustible species, such as the Erica genus (39% of the epidermal fragments in winter samples). Even when grassland habitat was utilized, in spring and summer, one-third of the diet was from woody species. Some bovines, such as the Alberes cattle breed, can therefore survive year-round in a forest habitat with little forage supplementation, and the consumption of a predominantly woody diet would be expected to reduce forest fire hazards. Resumen En este trabajo se determinó la composición anual de la dieta de una población semi-salvaje que habita el Parque Natural de la Albera (Paratge Natural d'Interè s Nacional de l'Albera) en el NE de Españ a. El estudio se llevó a cabo desde Junio de 2002 hasta Junio de 2004, a partir del análisis del contenido de 120 muestras fecales. Las especies leñ osas, principalmente de los géneros Quercus y Erica constituyeron la mayor parte de la dieta, alcanzando el 89% de la misma en invierno. Sin embargo, en primavera y verano la proporción de especies leñ osas y herbáceas fue diferente según el hábitat donde se recogieron las muestras. Las muestras recogidas en los bosques tuvieron el 67% de especies leñ osas en verano mientras que las recogidas en los pastizales solamente un 44%. Los resultados muestran que la población de ganado Alberes pastorea activamente en los bosques Mediterráneos y consume altas proporciones (39% de los fragmentos epide´rmicos en las muestras de invierno) del ge´nero Erica, cuyas especies son altamente combustibles. Se concluye que algunos bovinos, como la raza Alberes, pueden sobrevivir a lo largo del añ o en ambientes forestales, con escasa suplementación de alimento y que además el hecho de mantener una dieta predominantemente leñ osa podría contribuir a reducir el riesgo de incendio forestal.

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