Polymorphisms in bovine immune genes and their associations with somatic cell count and milk production in dairy cattle

Abstract

BackgroundMastitis, an inflammation of the mammary gland, is a major source of economic loss on dairy farms. The aim of this study was to quantify the associations between two previously identified polymorphisms in the bovine toll-like receptor 2 (TLR2) and chemokine receptor 1 (CXCR1) genes and mammary health indictor traits in (a) 246 lactating dairy cow contemporaries representing five breeds from one research farm and (b) 848 Holstein-Friesian bulls that represent a large proportion of the Irish dairy germplasm. To expand the study, a further 14 polymorphisms in immune genes were included for association studies in the bull population.ResultsTLR4-2021 associated (P < 0.05) with both milk protein and fat percentage in late lactation (P < 0.01) within the cow cohort. No association was observed between this polymorphism and either yield or composition of milk within the bull population. CXCR1-777 significantly associated (P < 0.05) with fat yield in the bull population and tended to associate (P < 0.1) with somatic cell score (SCS) in the cows genotyped. CD14-1908 A allele was found to associate with increased (P < 0.05) milk fat and protein yield and also tended to associate with increased (P < 0.1) milk yield. A SERPINA1 haplotype with superior genetic merit for milk protein yield and milk fat percentage (P < 0.05) was also identified.ConclusionOf the sixteen polymorphisms in seven immune genes genotyped, just CXCR1-777 tended to associate with SCS, albeit only in the on-farm study. The lack of an association between the polymorphisms with SCS in the Holstein-Friesian data set would question the potential importance of these variants in selection for improved mastitis resistance in the Holstein-Friesian cow.

Toll like receptor 4 (TLR4) gene polymorphism and its association with somatic cell score and milk production traits in Indian dromedary camels

“…Contrary to the reports of high genetic polymorphism in other livestock species, 20 , 29 , 32 we found no SNPs in the exonic region and only one SNP at the intron-1 region. However, our findings were similar to studies in bovines, pigs and ovines which also reported polymorphism in the intronic regions.…”

Toll like receptor 4 (TLR4) gene polymorphism and its association with somatic cell score and milk production traits in Indian dromedary camels

“…Contrary to the reports of high genetic polymorphism in other livestock species, 20 , 29 , 32 we found no SNPs in the exonic region and only one SNP at the intron-1 region. However, our findings were similar to studies in bovines, pigs and ovines which also reported polymorphism in the intronic regions.…”

Untitled

“…infection. On the contrary to the present study, association study by Beecher et al (2010) and Miseikiene et al (2020) determined that there was no association in TLR4 genotypes with SCS in Holstein-Friesian cattle.…”

Variation in the Toll-like Receptor 4 (TLR4) gene affects milk traits in dairy cows

“…The finding that B was associated with increased milk fat and protein percentage, and decreased milk yield; is consistent with the report of Beecher et al (2010). However, some differences occur between our findings and those of Beecher et al (2010). For example, the effect of variation on milk fat and protein percentage they described was only observed in late lactation, and not in either early or mid-lactation.…”

Toll like receptor 4 (TLR4) gene polymorphism and its association with somatic cell score and milk production traits in Indian dromedary camels

“…Contrary to the reports of high genetic polymorphism in other livestock species, 20 , 29 , 32 we found no SNPs in the exonic region and only one SNP at the intron-1 region. However, our findings were similar to studies in bovines, pigs and ovines which also reported polymorphism in the intronic regions.…”

Untitled

“…infection. On the contrary to the present study, association study by Beecher et al (2010) and Miseikiene et al (2020) determined that there was no association in TLR4 genotypes with SCS in Holstein-Friesian cattle.…”

Variation in the Toll-like Receptor 4 (TLR4) gene affects milk traits in dairy cows

“…The finding that B was associated with increased milk fat and protein percentage, and decreased milk yield; is consistent with the report of Beecher et al (2010). However, some differences occur between our findings and those of Beecher et al (2010). For example, the effect of variation on milk fat and protein percentage they described was only observed in late lactation, and not in either early or mid-lactation.…”

Toll like receptor 4 (TLR4) gene polymorphism and its association with somatic cell score and milk production traits in Indian dromedary camels

“…Contrary to the reports of high genetic polymorphism in other livestock species, 20 , 29 , 32 we found no SNPs in the exonic region and only one SNP at the intron-1 region. However, our findings were similar to studies in bovines, pigs and ovines which also reported polymorphism in the intronic regions.…”

Untitled

“…infection. On the contrary to the present study, association study by Beecher et al (2010) and Miseikiene et al (2020) determined that there was no association in TLR4 genotypes with SCS in Holstein-Friesian cattle.…”

Variation in the Toll-like Receptor 4 (TLR4) gene affects milk traits in dairy cows

“…The finding that B was associated with increased milk fat and protein percentage, and decreased milk yield; is consistent with the report of Beecher et al (2010). However, some differences occur between our findings and those of Beecher et al (2010). For example, the effect of variation on milk fat and protein percentage they described was only observed in late lactation, and not in either early or mid-lactation.…”