The effect of paratuberculosis on milk yield—A systematic review and meta-analysis

Abstract

Bovine paratuberculosis is a disease characterized by chronic granulomatous enteritis causing protein-losing enteropathy. Adverse effects on animal productivity are key drivers in the attempt to control paratuberculosis at the farm level. Economic models require an accurate estimation of the production effects associated with paratuberculosis. The aim of this study was to conduct a systematic review and meta-analysis to investigate the effect of paratuberculosis on milk production. A total of 20 effect estimates from 15 studies were included in the final meta-analysis. Substantial between-study heterogeneity was observed. Subgroup analysis by case definition and study design was carried out to investigate heterogeneity. The majority of between-study variation was attributed to studies that defined cases on serology. Calculation of a pooled effect estimate was only appropriate for studies that defined cases by organism detection. A reduction in milk yield, corrected for lactation number and herd of origin of 1.87 kg/d, equivalent to 5.9% of yield, was associated with fecal culture or PCR positivity in individual cows.

Effects of subclinical Mycobacterium avium ssp. paratuberculosis infection on some physiological parameters, health status and production in dairy cows

“…However, other authors did not find any difference (Johnson et al, 2001) or even reported an increased milk yield (McNab et al, 1991) in MAP-infected cows. According to a recent meta-analysis by McAloon et al (2016), the calculated combined effect of MAP infection was -1.87 kg milk/cow per day, estimated to correspond to a 5.9% decrease in milk yield, which is lower than the results of the present study. According to Donat et al (2014b), the decrease in milk production of MAP-positive cattle depends on the within-herd prevalence.…”

Adaptive Test Schemes for Control of Paratuberculosis in Dairy Cows

“…MAP can be shed by subclinical as well as clinical cattle, and while the progress of infection can be slow, the subclinical phase can last for several years [2]. Subclinical dairy cows are subject to lower milk yield and lower slaughter value, causing an economic loss for the dairy farmer [3,4,5]. Ultimately, the clinical phase can result in diarrhea and death.…”

Herd-level prevalence of selected endemic infectious diseases of dairy cows in Great Britain

“…paratuberculosis (MAP), infectious bovine rhinotracheitis, and liver fluke are generally regarded as being widespread and endemic in the United Kingdom (Carslake et al, 2011;Sekiya et al, 2013). These diseases are known to have a significant effect on dairy production due to their effects on fertility (Fray et al, 2000;Lanyon et al, 2014;Walz et al, 2015), milk production (Tiwari et al, 2007;McAloon et al, 2016), and, subsequently, culling (Murphy et al, 2006;Smith et al, 2010).…”

“…paratuberculosis (MAP), infectious bovine rhinotracheitis, and liver fluke are generally regarded as being widespread and endemic in the United Kingdom (Carslake et al, 2011;Sekiya et al, 2013). These diseases are known to have a significant effect on dairy production due to their effects on fertility (Fray et al, 2000;Lanyon et al, 2014;Walz et al, 2015), milk production (Tiwari et al, 2007;McAloon et al, 2016), and, subsequently, culling (Murphy et al, 2006;Smith et al, 2010).In Great Britain (GB) in 2005, the total costs of dairy and beef cattle endemic infectious diseases (disease, control, and prevention) were estimated to be as high as £10 million ($12.4 million) for Johne's disease and £61.1 million ($75.7 million) per annum for BVDV (Bennett and Ijpelaar, 2005). However, due to a lack of reliable prevalence data at national level, these figures are likely to underestimate the true situation.…”