Effect of Mycobacterium avium subsp. paratuberculosis serostatus on carcass weight and conformation and fat cover scores

Abstract

The paper was designed to assess the influence of Mycobacterium avium subsp. paratuberculosis (MAP) infection status of cows at culling (antibody positive vs negative) on carcass traits: weight and conformation and fat cover scores. A generalized least squares linear model was used to assess the influence of MAP on weight. Subsequently, a random effects logistic regression was completed in order to model the relation between MAP and conformation score (fair vs poor carcasses). A random effects ordered logistic model was used to estimate the influence on fat cover. The results indicated that seropositives had carcass weights 58. 45 (34.65-83.35) kg lower than seronegatives. Regarding conformation score, the odds of having poor conformation instead of fair was 3.85 (1.35-11.85) times higher in seropositives. The odds of seropositives achieving a higher fat cover was approximately 5 (1.41-9.09) times lower than the odds for seronegatives. The estimated effects could be useful when assessing the economic benefits of a paratuberculosis control program.Additional key words: Johne´s disease, carcass traits, serology, ELISA, economic losses.Correspondence should be addressed to Francisco J. Dieguez: franciscojavier.dieguez@usc.es

A scoping review on associations between paratuberculosis and productivity in cattle

“…A possible association between PTB and meat quantity and quality was investigated in several studies. A reduction in carcass weight of −39.78 kg or −12.4% ( p = < 0.0001) ( 70 ) and −58.45 kg ( p = < 0.001) ( 80 ) for serum ELISA positive cows was reported. The slaughter weight for serum ELISA positive cows was reduced by up to −10% and up to −15% if they were also fecal culture positive, resulting in a reduction of slaughter value of −17% and −31%, respectively ( 81 ).…”

“…In another study, losses were estimated at US$ 296/per clinical case ( 49 ). Mato et al ( 80 ) found that seropositive cows were more likely to have poor carcass quality. They were 3.85 times more likely to have a poor carcass conformation score instead of fair and they had significantly lower fat cover scores.…”

Factors Associated with the Introduction of Mycobacterium avium spp. Paratuberculosis (MAP) into Dairy Herds in Galicia (North-West Spain): The Perception of Experts

“…This disease causes serious economic losses in dairy farming, mainly as a result of reduced milk yield [ 3 , 4 ], increased susceptibility to other diseases, particularly mammary infections [ 5 ], loss of bodyweight [ 6 ] and consequential premature culling [ 7 ]. Paratuberculosis has also been related to reduced fertility rates [ 4 , 8 ].…”

Short communication: Risk factors associated with Mycobacterium avium ssp. paratuberculosis introduction into dairy herds in Galicia, northwestern Spain

“…milk yield (Richardson and More, 2009), increased susceptibility to other diseases, especially mammary infections (Tiwari et al, 2005), loss of body weight (Mato et al, 2017), and consequential premature culling (Mato et al, 2015). Paratuberculosis has also been related to reduced fertility rates (Smith et al, 2010).…”