Single nucleotide polymorphisms in immunity-related genes and their association with mastitis in Chilean dairy cattle

Abstract

ABSTRACT. Mastitis remains a major cattle disease with great global economic implications. Various approaches are currently employed in attempts to improve understanding of mastitis resistance and develop phenotypic markers for use in breeding programs (e.g., somatic cell score), including QTL discovery, wide-genome association studies, and identification of candidate genes related to immune function. This study evaluated three single nucleotide polymorphisms contained in Toll-like receptor 4 (TLR4) and lactoferrin (LF) genes associated with mastitis traits: TLR4 P-226, TLR4 2021, and LF P-28. Genotyping was performed by restriction fragment length polymorphism-polymerase chain reaction (PCR) and high-resolution melting quantitative PCR from genomic DNA of four dairy cattle breeds (Holstein, Jersey, Montbeliarde, and Overo Colorado) previously classified as healthy, with clinical or with subclinical mastitis. The high-resolution melting quantitative PCR allowed genotyping of each locus and resulted in allele frequencies indicating that all loci were in Hardy-Weinberg equilibrium. The TT genotype of TLR4 2021 was significantly associated with the healthy condition, but no associations with somatic cell score were evident. Further studies are therefore necessary in order Single nucleotide polymorphisms and mastitis in dairy cattle to confirm the results of this investigation.

Innate immune responses induced by lipopolysaccharide and lipoteichoic acid in primary goat mammary epithelial cells

“…Numerous studies have demonstrated a potential role for TLR2 and TLR4 in the development of mastitis in dairy cattle [10], resistance to bacteria [11], and ability to affect the level of bacteria in milk [12]. Both LPS and LTA are able to cause an inflammatory response via TLR signaling [13, 14].…”

Association of <i>TLR4</i> and <i>CARD15/NOD2</i> polymorphisms with SCC in Holstein–Friesian cattle

“…In our research, the most frequent variant found at this locus was allele C (62 %). Similarly, Carvajal et al (2013) found allele C as the predominant variant in Chilean dairy cattle. However, in a Canadian Holstein, the predominant allele was G (60 %) (Sharma et al, 2006).…”

Molecular genetic markers of economically important traits in dairy cattle

“…The G allele was associated with increased protein con tent in milk, and allele delCCT was associated with in creased milk yield and fat content [56] H3 haplotype (G 1 C 2 G 3 T 4 C 5 C 6 T 7 ) was associated with reduced levels of saturated fatty acids and lau ric acid (C12:0) and high concentration of unsatur ated and monounsaturated fatty acids as compared to haplotype H1 (G 1 C 2 C 3 C 4 A 5 C 6 A 7 ) during first 3 months of lactation Associated with the percentage of fat and protein in milk at 141-305 days of lactation [69] TT genotype is associated with resistance to mastitis [86] Transition protein 2 (TNP2) g.269G>A (exon 1), g.480C>T (intron 1), g.1536C>T (3' UTR)…”