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Summary: Background: Vitiligo and melanoma are relatively common disorders in grey Pura Raza Español horses and other horse breeds with grey‐coloured coats. Objectives: To determine the breed prevalence, environmental risks factors and estimate the genetic parameters for vitiligo and melanoma in Pura Raza Español horses. Study design: Retrospective cohort study. Methods: We analysed data from a large worldwide population of Pura Raza Español horses. The database included the vitiligo and melanoma scores, on either a four‐ or six‐point linear scale, of 11,436 horses. Genetic parameters were estimated using a Bayesian genetic animal model including the four associated environmental risk factors as systematic effects. Inbreeding was used as a covariate, and animal and residual effects were included as random effects. Results: Of the horses included in the study, 2.8 and 20.5% showed some traces of vitiligo around the eyes and mouth, respectively, while 1.6% showed varying degrees of melanoma. Age, coat colour and inbreeding were significantly associated with the three outcomes studied. The estimated heritability for the whole population was 0.09 (s.d. +0.019), 0.44 (s.d. +0.031) and 0.13 (s.d. +0.037), for eye vitiligo score, nostril vitiligo score and melanoma scores respectively. The genetic correlations ranged from 0.42 (s.d. +0.084) between eye and nostril vitiligo score to 0.15 (s.d. +0.096) between nostril vitiligo and melanoma. Main limitations: Vitiligo scores for the perianal regions were not collected. The veterinarian responsible for each assessment was not recorded. Conclusions: Vitiligo and melanoma are prevalent in this population and those environmental risk factors and genetics both have an effect on the clinical expression of the diseases. These findings may help to reduce prevalence through breeding programmes. [ABSTRACT FROM AUTHOR]

Reasons for performing study Cresty neck is a relatively common morphological defect in Pura Raza Español horses and other Baroque type horse breeds, which adversely affects the breeding industry. Objectives To establish the within-breed prevalence, possible associated factors and heritability of cresty neck in Pura Raza Español horses. Study design Cross-sectional analysis of a large worldwide database of Pura Raza Español horses. Methods The database included evaluations of 10,929 Pura Raza Español horses from 24 countries. Cresty neck score, on a 9 point scale, girth-to-height ratio, height at the withers, length of neck, head-neck junction and neck-body junction were recorded. A Bayesian genetic animal model included the following systematic effects: girth-to-height ratio, age, sex, coat colour and geographical area of the stud. Animal and residual effects were included as random effects. Results Within this Pura Raza Español population , 8.91% had a cresty neck score ≥5, which is the threshold for penalty or disqualification in the studbook of the breed. The age, sex, coat colour and stud geographical area were significantly associated with cresty neck score. The estimated heritability coefficient for cresty neck score was 0.37 (s.d. = 0.034) and genetic correlation between cresty neck score and other conformational traits ranged from −0.06 (height-at-withers) to −0.21 (neck-body junction). Conclusions Cresty neck is a prevalent defect in Pura Raza Español horses, associated with age, sex, coat colour and other conformational traits, with a moderate level of heritability. Breeding to select against this condition may therefore be beneficial in this breed. [ABSTRACT FROM AUTHOR]

We partially sequenced the mitochondrial hypervariable region 1 ( HVR1) in 60 goats belonging to six Spanish breeds. The analysis of these and previously published sequences reveals a weak phylogeographical structure in the Iberian Peninsula breeds. Individuals from a single breed did not group into a single cluster. Furthermore, individuals from different breeds often shared single phylogenetic tree branches after UPGMA analysis. This could reflect the non-existence of breed isolation because of traditional seasonal pastoralism and annual long-distance migrations. Three goats belonging to the C maternal lineage were found, demonstrating a wider than previously thought distribution for this lineage. [ABSTRACT FROM AUTHOR]