Genetic resistance to bacterial diseases of animals

Abstract

Despite traditional disease control measures, losses attributable to infectious diseases continue to impede the livestock industries. An alternative approach to this problem is genetic disease resistance involving both immune and non-immune mechanisms, which is the inherent capacity of a previously unexposed animal to resist disease when challenged by pathogens. Although the nurturing environment influences variability in disease expression, natural resistance has been found to be inheritable and is transmitted from parent to offspring. Thus, an alternative approach to enhancing animal health management systems is to increase the overall level of genetic resistance at herd and population levels by using selective breeding programmes. The purpose of this review is to bring veterinarians, regulatory officials, industry representatives and animal technicians up to date with the principles and applications of genetic resistance as an adjunct to traditional interventions to control bacterial diseases of livestock. Although genetic resistance to bacterial diseases is often regulated by multiple genes controlling different processes of the host-pathogen interaction, the genetics of natural resistance is being unravelled increasingly by identification and characterisation of candidate genes, microsatellite markers and comparative gene mapping, to develop more practical methods of application.

Identification of single nucleotide polymorphisms in the bovine solute carrier family 11 member 1 (SLC11A1) gene and their association with infection by Mycobacterium avium subspecies paratuberculosis

“…The fragment described by Hořín et al (1999) was amplified using the primers and PCR conditions described by the same author. The (GT) n microsatellite of Adams and Templeton (1998) was analyzed using the primers and PCR conditions described by Barthel et al (2000). The SNP were genotyped using SNPlex technology by Applied Biosystems.…”

“…A total of 543 animals were analyzed for the microsatellite of Adams and Templeton (1998). Three alleles of 175, 177, and 179 bp were detected, which correspond to (GT) 13 , (GT) 14 , and (GT) 15 , respectively (Paixao et al, 2006).…”

“…Recently, a strong genetic influence of Slc11a1 on the innate susceptibility of mice to infection with MAP has been established (Roupie et al, 2008). For cattle, a genetic association has been described between a microsatellite-type polymorphism (GT) n in the 3′-untranslated region (UTR) of the gene and Brucella abortus infection in Holstein-Friesian cattle (Adams and Templeton, 1998). In the same region of the gene, Estonba et al (2005) analyzed a larger fragment described previously (Hořín et al, 1999), which includes the (GT) n microsatellite described by Adams and Templeton (1998) and a further adjacent (GT) n repeat.…”

“…For cattle, a genetic association has been described between a microsatellite-type polymorphism (GT) n in the 3′-untranslated region (UTR) of the gene and Brucella abortus infection in Holstein-Friesian cattle (Adams and Templeton, 1998). In the same region of the gene, Estonba et al (2005) analyzed a larger fragment described previously (Hořín et al, 1999), which includes the (GT) n microsatellite described by Adams and Templeton (1998) and a further adjacent (GT) n repeat. This study detected a genetic association with MAP infection in a naturally infected Holstein-Friesian herd.…”

“…With the aim of testing for its potential involvement in susceptibility to MAP infection, we conducted a SNP discovery approach on bovine SLC11A1 gene and performed a candidate gene type genetic association test between these SNP and MAP infection in the HolsteinFriesian breed. In this study we also sought to establish the relationship between microsatellite (GT) n of Adams and Templeton (1998), the fragment analyzed by Estonba et al (2005) in the same 3′-UTR, and the SNP covering the whole length of the SLC11A1 gene.…”