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The LIM and SH3 protein 1 (LASP1) and the ligand dependent nuclear receptor corepressor-like (LCORL) genes were selected as candidates in this study of growth and height of equines of the Brazilian Pony breed. Until now, no genomic studies on the morphometry of Brazilian ponies have been reported in the literature. Both genes are correlated with osteogenesis and transcription factor TFIID of genes involved in skeletal growth, respectively. The objective of this study was to analyze two height associated mutations in LASP1 and LCORL genes and their associations with equine morphometry. This is the first study that genotyped these known variants in the Brazilian Pony breed. The DNA was extracted from hair follicles and the two variants were amplified by PCR. The genotyping was performed by RFLP markers through restriction enzyme cleavage; the samples were submitted to capillary electrophoresis for allelic discrimination by size; and the polymorphism was identified and associated with the morphometric measures of the animals. Regarding the LASP1 gene, the ponies with genotypes G/G and G/A presented the smallest measures for head length, neck length, withers height, croup height and body length. Mutation analysis [T > C] of the LCORL gene identified the T/T genotype in all ponies except one individual of the control group, with shoulder height of 1.69 m, which presented the C/C genotype, confirming the association of this gene with the height of horses of the Brazilian Pony breed. The stature and morphometry of horses of this breed were influenced by variants of the LASP1 gene.

Genome-wide association testing facilitates the identification of genetic variants associated with complex traits. Mapping genes that promote genetic resistance to mastitis could reduce the cost of antibiotic use and enhance animal welfare and milk production by improving outcomes of breeding for udder health. Using imputed whole-genome sequence variants, we carried out association studies for 2 traits related to udder health, udder index, and milking speed in Nordic Holstein cattle. A total of 4,921 bulls genotyped with the BovineSNP50 BeadChip array were imputed to high-density genotypes (Illumina BovineHD BeadChip, Illumina, San Diego, CA) and, subsequently, to whole-genome sequence variants. An association analysis was carried out using a linear mixed model. Phenotypes used in the association analyses were deregressed breeding values. Multitrait meta-analysis was carried out for these 2 traits. We identified 10 and 8 chromosomes harboring markers that were significantly associated with udder index and milking speed, respectively. Strongest association signals were observed on chromosome 20 for udder index and chromosome 19 for milking speed. Multitrait meta-analysis identified 13 chromosomes harboring associated markers for the combination of udder index and milking speed. The associated region on chromosome 20 overlapped with earlier reported quantitative trait loci for similar traits in other cattle populations. Moreover, this region was located close to the FYB gene, which is involved in platelet activation and controls IL-2 expression; FYB is a strong candidate gene for udder health and worthy of further investigation.