Abstract #T304
Section: Breeding and Genetics (posters)
Session: Breeding and Genetics II
Format: Poster
Day/Time: Tuesday 7:30 AM–9:30 AM
Location: Exhibit Hall A
Session: Breeding and Genetics II
Format: Poster
Day/Time: Tuesday 7:30 AM–9:30 AM
Location: Exhibit Hall A
# T304
Genome-wide association study on health and reproductive traits in US Holstein cattle.
Fernando Brito1, Guilherme Rosa1, Pablo Pinedo*2, Jose Santos3, Gustavo Schuenemann4, Rodrigo Bicalho5, Ricardo Chebel3, Klibs Galvao3, Robert Gilbert5,9, Sandra Rodriguez-Zas6, Christopher Seabury7, John Fetrow8, William Thatcher3, 1University of Wisconsin, Madison, WI, 2Colorado State University, Fort Collins, CO, 3University of Florida, Gainesville, FL, 4The Ohio State University, Columbus, OH, 5Cornell University, Ithaca, NY, 6University of Illinois, Urbana-Champaign, IL, 7Texas A&M University, College Station, TX, 8University of Minnesota, Saint Paul, MN, 9Ross University, Basseterre, St. Kitts and Nevis, West Indies.
Key Words: dairy cattle, fertility, health traits
Genome-wide association study on health and reproductive traits in US Holstein cattle.
Fernando Brito1, Guilherme Rosa1, Pablo Pinedo*2, Jose Santos3, Gustavo Schuenemann4, Rodrigo Bicalho5, Ricardo Chebel3, Klibs Galvao3, Robert Gilbert5,9, Sandra Rodriguez-Zas6, Christopher Seabury7, John Fetrow8, William Thatcher3, 1University of Wisconsin, Madison, WI, 2Colorado State University, Fort Collins, CO, 3University of Florida, Gainesville, FL, 4The Ohio State University, Columbus, OH, 5Cornell University, Ithaca, NY, 6University of Illinois, Urbana-Champaign, IL, 7Texas A&M University, College Station, TX, 8University of Minnesota, Saint Paul, MN, 9Ross University, Basseterre, St. Kitts and Nevis, West Indies.
This study was carried out to identify genomic regions associated with health and reproductive traits in Holstein cows, including lameness (LS), metritis (MET), mastitis (MAT), resumption of cyclicity (CY), pregnancy 60 d after first AI (P60), and a reproductive index (IndexP60). Phenotypic information was collected on 11,733 cows calving during warm and cool seasons in 16 farms located in 4 US regions: Northeast (4 herds), Midwest (6 herds), Southeast (1 herd), and the Southwest (5 herds). From those, 2,505 cows were selectively genotyped using the Illumina Bovine HD SNP Chip. Genotypes were edited to remove SNP located on sex and mitochondrial chromosomes, unknown map position, call rate <0.95, minor allele frequency <0.01, and deviation from HWE (P < 10−10), resulting on 592,788 SNPs retained for further analyses. GBLUP and genome-wide association studies (GWAS) were performed using a linear model for IndexP60 and logistic models for the other traits. The AI-REML algorithm was used to estimate variance components, and marker effects were evaluated using the score test. Although heritability estimates were low for all traits, some interesting peaks were found in the GWAS analyses (Table 1). The GWAS analyses indicated that 16 genes on bovine chromosomes 1, 3, 6, 10, 11, 12, 14, 15, 22, and 29 were associated with the traits of interest. From those, chromosomes 3 and 6 presented common regions for P60 and IndexP60, and chromosome 22 presented common regions for CY, LS, P60 and IndexP60. The chromosomal regions identified have confirmed several previous findings that may contribute to variation in fertility and health traits in dairy cattle. Table 1. Estimates of heritability (h2), number of significant SNP hits (P-value < 1e-5) and genes located within 20 kb upstream and downstream of the SNP
| Trait | h2 (SE) | No. of hits | Genes |
| Lameness at 40 DIM | 0.030 (0.048) | 21 | RIMS2, U6 |
| Metritis | 0.063 (0.026) | 3 | FHIT, OPCML |
| Mastitis | 0.047 (0.042) | 1 | — |
| Resumption of cyclicity | 0.070 (0.026) | 5 | STAC |
| Pregnancy 60 d after first AI | 0.110 (0.024) | 49 | ABI3BP, FOXJ3, GC-201, NBEA, NPFFR2, SLC7A8, and TRIM71 |
| Reproductive index | 0.126 (0.029) | 38 | FOXJ3, GC, NPFFR2, and TRIM71 |
Key Words: dairy cattle, fertility, health traits
