Association between cow reproduction and calf growth traits and ELISA scores for paratuberculosis in a multibreed herd of beef cattle

Abstract

The objective of this research was to assess the association between 4 cow reproductive and weight traits, and 2 preweaning calf traits and ELISA scores for paratuberculosis (0 = negative, 1 = suspect, 2 = weak-positive, and 3 = positive) in a multibreed herd of cows ranging from 100% Angus (A) to 100% Brahman (B). Cow data were 624 gestation lengths (GL), 358 records of time open (TO), 605 calving intervals (CI), and 1240 weight changes from November to weaning in September (WC) from 502 purebred and crossbred cows. Calf data consisted of 956 birth weights (BWT), and 923 weaning weights adjusted to 205 d of age (WW205) from 956 purebred and crossbred calves. Traits were analyzed individually using multibreed mixed models that assumed homogeneity of variances across breed groups. Covariances among random effects were assumed to be zero. Fixed effects were year, age of cow, sex of calf, year x age of cow interaction (except WC), age of cow x sex of calf interaction (only for WC), and covariates for B fraction of sire and cow, heterosis of cow and calf, and ELISA score. Random effects were sire (except for TO and CI), dam, and residual. Regression estimates of cow and calf traits on ELISA scores indicated that lower cow fertility (longer TO), lower ability of cows to maintain weight (negative WC), lower calf BWT, and lower calf WW205 were associated with higher cow ELISA scores. Further research on the effects of subclinical paratuberculosis in beef cattle at regional and national levels seems advisable considering the large potential economic cost of this disease.

Comparison of calf weaning weight and associated economic variables between beef cows with and without serum antibodies against or isolation from feces of Mycobacterium avium subsp paratuberculosis

“…In the present study, calf AWW decreased to a greater extent as its dam' s antibody titer against MAP or amount of MAP isolated from BCF increased in a nonlinear manner. Results of another study 4 indicate that the AWW of calves from cows classified as suspect, positive, or strongly positive by means of a serum ELISA decreased linearly by 2.3 kg (5.1 lb; 95% CI, 0.5 to 4.1 kg [1.1 to 9.0 lb]), 4.6 kg (10.1 lb; 95% CI, 2.8 to 6.4 kg [6.2 to 14.1 lb]), and 6.9 kg (15.2 lb; 95% CI, 1.6 to 12.2 kg [3.5 to 26.8 lb]), respectively, compared with that of calves from cows that were classified as negative. The linear nature of the association between calf AWW and ELISA score in that study 4 was most likely the result of the ELISA score being modeled as a linear covariate, ent study overlaid on that plot.…”

Early Weight Development of Goats Experimentally Infected with Mycobacterium avium subsp. paratuberculosis

“…More related to our study is the recent study by Elzo et al (2009) in which they investigated the association of calves and their growth traits with the ELISA scores for Johne’s disease of their mothers [ 26 ]. While the effect of cows in the subclinical stage of Johne’s disease on birth weight of their calves was rather small and less significant, calves from ELISA positive cows were significantly lighter at weaning than calves from ELISA negative cows.…”

Effect of Mycobacterium avium subsp. paratuberculosis infection status on culling and calving difficulty in dairy cattle

“…These reasons include a decrease in milk production (Kudahl et al, 2004;Beaudeau et al, 2007;Aly et al, 2010) and a greater susceptibility to other diseases, especially mammary infections (Tiwari et al, 2005;Villarino and Jordan, 2005). JD has also been related to a reduction in fertility rates (Tiwari et al, 2005;Diéguez et al, 2008); antibody positive animals had significantly higher number of days open (Elzo et al, 2009). Additionally, Raizman et al (2007a) indicated that JD was also associated with pneumonia.…”