The genetics of antibody response to paratuberculosis in dairy cattle

Abstract

Genetic parameters were estimated for antibody response to paratuberculosis (Mycobacterium avium ssp. paratuberculosis) using milk ELISA test results, collected and analyzed by National Milk Records, from Holstein Friesian cows on UK dairy farms in their first 3 lactations. Milk ELISA test results were obtained from 2007 to 2012 and combined with milk recording data and pedigree information. The reduced data set edited for the purposes of genetic parameter estimation consisted of 148,054 milk ELISA records from 64,645 lactations in 40,142 cows of 908 sires, recorded in 641 herds. Milk ELISA test results were log-transformed and univariate analysis of 3 alternative animal models and equivalent sire models were considered. The most appropriate model included additive genetic and permanent environmental random effects, whereas maternal effects were significant according to likelihood ratio test and Akaike's information criterion but not for Bayesian information criterion. Heritability and repeatability estimates were 0.06 and 0.37, respectively, for the chosen animal model and its equivalent sire model. A subset of the data including herds with greater than 10% positive tests gave a slightly higher heritability of 0.08. Favorable but generally low significant genetic correlations were obtained between antibody response with 305-d milk yield (-0.16), 305-d protein yield (-0.16), log-transformed lactation-average somatic cell count (0.15), and the number of mastitis episodes (0.22). Thus, selection on the antibody response to paratuberculosis, should not be detrimental to production or udder health traits. Testing cattle for paratuberculosis is important for its use in control programs and although the heritability of antibody response was low, breeding against the disease might be a good prospect as a preventative measure to assist together with other approaches in an overall control strategy.

The genetic architecture of milk ELISA scores as an indicator of Johne's disease (paratuberculosis) in dairy cattle

“…Differences among these studies may be due to many factors such as various diagnostic tests, variable disease incidence in the studied populations, different management practices, the population under investigation (as genetic parameters are population-specific), trait definitions, statistical models, pedigree depth, data editing, and others. In our study, maternal effects were not a significant source of variation (P > 0.05) and, therefore, were not included in the statistical models; this is in agreement with other studies that reported contribution of maternal effects to JD phenotypic variance lower than 1.5% (Mortensen et al, 2004;Attalla et al, 2010;Pritchard et al, 2017a).…”

“…A higher genetic merit for milk yield was not associated with higher susceptibility to MAP infection. In general, Pritchard et al (2017a) reported significant positive genetic correlations between milk antibody response and udder health traits such as log-transformed SCC and number of mastitis episodes, implying that animals predisposed to higher SCC or mastitis may also mount a higher antibody response during MAP infection; therefore, selection for lower MAP antibody response could be favorable for udder health. Shook et al (2012) reported unfavorable genetic correlations that ranged from 0.14 to 0.22 for MAP infection with milk production traits; however, these estimates were associated with high confidence intervals that also contained zero values.…”

“…Desirable significant antagonistic correlations between MAP infection status and calving to first service and longevity were observed in our study ( Table 6), implying that selection for these traits could reduce susceptibility to MAP infection (as measured by milk ELISA). Pritchard et al (2017a) reported that genetic correlations between MAP antibody response and different fertility traits were low, negative, and not significant. Additionally, Berry et al (2010) found low, nonsignificant correlations between MAP serological response and calving interval and perinatal mortality.…”

Short communication: Heritability of susceptibility to infection by Mycobacterium avium ssp. paratuberculosis in Holstein cattle

“…(Lynch and Walsh, 1998). Heritability estimates for LM and TPM are in good agreement with previous reports of linear model heritability estimates, which ranged from <0.01 to 0.183 (Koets et al, 2000;Mortensen et al, 2004;Gonda et al, 2006;Hinger et al, 2008;Attalla et al, 2010;Berry et al, 2010;van Hulzen et al, 2011;Zare et al, 2014;Pritchard et al, 2017), and previous threshold model estimates, which ranged from 0.052 to 0.283 (Gonda et al, 2006;Hinger et al, 2008;Attalla et al, 2010;Berry et al, 2010;Küpper et al, 2012;Shook et al, 2012;Zare et al, 2014). Heritability estimates increased as data were restricted to herds with presumed higher MAP exposure for both linear and threshold model analyses, as previously observed (van Hulzen et al, 2011).…”

Estimation of heritability for immunoglobulin concentrations in colostrum and serum in Holstein cows and their calves

“…studies, heritability for serum total protein (STP) and some immunoglobulins (Ig) were estimated in some studies (Jensen and Christensen 1975;Jensen et al 1982;Mallard et al 1983;Muggli et al 1984;Mazengara et al 1985;Gilbert et al 1988a;Burton et al 1989;Detilleux et al 1994). On the other hand, while in some studies genetic parameters for natural antibodies associated with mastitis ( Thompson-Crispi et al 2013) and antibody development against paratuberculosis (Pritchard et al 2017) were estimated in the Holsteins, some other studies focused on the development of resistance to the bovine respiratory disease through selection (Snowder et al 2006;Snowder 2009;Cockrum et al 2016).…”