scholarly journals Environmental sampling to assess the bioburden of Mycobacterium avium subspecies paratuberculosis in drylot pens on California dairies

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e8081 ◽  
Author(s):  
Tapakorn Chamchoy ◽  
Deneice R. Williams ◽  
John M. Adaska ◽  
Randall J. Anderson ◽  
Sharif S. Aly
Keyword(s):  
Mycobacterium Avium ◽  
Environmental Samples ◽  
Mycobacterium Avium Subspecies Paratuberculosis ◽  
High Reliability ◽  
Intraclass Correlation ◽  
Economic Losses ◽  
Dairy Herds ◽  
Environmental Sampling ◽  
Sampling Protocol ◽  
Central California

Mycobacterium avium subspecies paratuberculosis (MAP) is a bacterium that can cause substantial economic losses in infected dairy herds due to reduced milk production and increased cow-replacement costs. In order to control MAP in dairies with drylot pens, a standardized environmental sampling protocol to quantify MAP in fecal slurry was developed based on an existing protocol for freestall pens. Specifically, following a 24 h hold of the flush, a grab sample of approximately 10 ml of fecal slurry was collected every 1 m along the flush lane of the drylot pens, avoiding individual cow fecal pats. To determine the reliability and repatability of the new environmental sampling protocol for estimation of MAP bioburden at the pen level, two collectors simultaneously collected fecal slurry samples every day for 3 days from six drylot cow pens on two Central California dairies. During the study period no cow movement between pens was allowed with the exception of sick cows. The study herds had MAP seroprevalence of 5.8% and 3.2%, respectively, based on whole pen serum ELISA results. Variance components models for quantitative real-time PCR (qPCR) results showed samples collected from different pens on different dairies accounted for greater variablitiy in MAP concentration (65%), while samples collected by different collectors had the least variability (0.1%). In contrast, variability in MAP concentration in environmental samples collected on different days had 25% variability. The intraclass correlation coefficient showed high reliability (93%) of environmental sampling simultaneously by different collectors. In contrast, the reliability of environmental sampling at different days was 65%, which was similar to the reliability for sampling by different collectors on different days. Investigators can expect high reliability when employing the new environmental sampling protocol along with qPCR testing of environmental samples from drylot pens.

scholarly journals Electrochemical Detection of Serum Antibodies Against Mycobacterium avium Subspecies paratuberculosis

2021 ◽  
Vol 8 ◽  
Author(s):  
Kaoru Hatate ◽  
J. Hunter Rice ◽  
Karsten Parker ◽  
J. Jayne Wu ◽  
Amy Turner ◽  
...  
Keyword(s):  
Electrochemical Detection ◽  
Mycobacterium Avium ◽  
Magnetic Beads ◽  
Mycobacterium Avium Subspecies Paratuberculosis ◽  
Diagnostic System ◽  
New Method ◽  
Economic Losses ◽  
Dairy Herds ◽  
Redox Active ◽  
Active Probe

Mycobacterium avium subsp. paratuberculosis (MAP) causes a chronic inflammatory intestinal disease, called Johne's disease (JD) in many ruminants. In the dairy industry, JD is responsible for significant economic losses due to decreased milk production and premature culling of infected animals. Test-and-cull strategy in conjunction with risk management is currently recommended for JD control in dairy herds. However, current diagnostic tests are labor-intensive, time-consuming, and/or too difficult to operate on site. In this study, we developed a new method for the detection of anti-M. paratuberculosis antibodies from sera of M. paratuberculosis-infected animals. M. paratuberculosis antigen-coated magnetic beads were sequentially reacted with bovine serum followed by a horseradish peroxidase (HRP)-labeled secondary antibody. The reaction of HRP with its substrate was then quantitatively measured electrochemically using a redox-active probe, ferrocyanide. After optimization of electrochemical conditions and concentration of the redox-active probe, we showed that the new electrochemical detection method could distinguish samples of M. paratuberculosis-infected cattle from those of uninfected cattle with greater separation between the two groups of samples when compared with a conventional colorimetric testing method. Since electrochemical detection can be conducted with an inexpensive, battery-operated portable device, this new method may form a basis for the development of an on-site diagnostic system for JD.

scholarly journals Detection of Mycobacterium avium subspecies paratuberculosis in environmental samples from infected Czech dairy herds

2021 ◽  
Vol 66 (No. 1) ◽  
pp. 1-7
Author(s):  
V Fichtelova ◽  
A Kralova ◽  
P Fleischer ◽  
V Babak ◽  
K Kovarcik
Keyword(s):  
Quantitative Pcr ◽  
Mycobacterium Avium ◽  
Environmental Samples ◽  
Diagnostic Method ◽  
Bacterial Culture ◽  
Dairy Herds ◽  
Environmental Sampling ◽  
Time Saving ◽  
Culture Positive

The objective of the present study was to evaluate the suitability of environmental sampling to screen Czech dairy herds to detect Mycobacterium avium ssp. paratuberculosis (MAP) and to find the most convenient location for the MAP detection in the lactating cow area. Environmental samples (ES, n = 72) from milking parlour holding pens (n = 19), milking alleyways (n = 19) and free-stall alleyways (n = 34) from 19 herds were simultaneously tested to detect MAP by a quantitative PCR (qPCR) and bacterial culture. Eight and thirteen samples from the milking parlour holding pens, twelve and eleven samples from the milking alleyways and eleven and eighteen samples from the free-stall alleyways were qPCR and culture positive, respectively. A 4.6 times higher probability of being culture positive than qPCR positive was detected for the assessable MAP detection results from the free-stall alleyways [P = 0.008 6, odds ration (OR) = 4.572 8)] and no association was found between the results from the milking parlour holding pens (P = 0.191 4) and the milking alleyways (P > 0.999 9) and the diagnostic method used. The percentage of qPCR-positive samples in the tested locations was detected for the milking alleyways (63.2%), free-stall alleyways and milking parlour holding pens. The herd infectious status was in agreement with 16 (84.2%), 14 (73.7%) and 12 (63.2%) qPCR results from the milking alleyways, free-stall alleyways (32.4%) and milking parlour holding pens (42.1%), respectively. No statistically significant differences were detected for these results (P = 0.396 1). MAP was detected by the qPCR and bacterial culture in all three locations where the ES were collected. We suggest an environmental sampling followed by MAP detection by qPCR as an easy-to-perform time-saving protocol for MAP screening in Czech dairy herds. Although the milking alleyways seem to be the most convenient location for the environmental sampling, this assumption was not statistically supported.

scholarly journals Modelling Bovine Granuloma Formation In Vitro upon Infection with Mycobacterium Avium Subspecies Paratuberculosis

2019 ◽  
Vol 6 (4) ◽  
pp. 80 ◽  
Author(s):  
J. Hunter Rice ◽  
Margaret M. McDaniel ◽  
Alyson Holland ◽  
Shigetoshi Eda
Keyword(s):  
Mycobacterium Avium ◽  
Mycobacterium Avium Subspecies Paratuberculosis ◽  
Clinical Signs ◽  
Host Cells ◽  
Economic Losses ◽  
Multiple Parameters ◽  
Cell Mediated Immune Response ◽  
A Cell ◽  
Vitro Model

Mycobacterium avium subspecies paratuberculosis (Map) causes chronic granulomatous disease in cattle and ruminant livestock, causing substantial economic losses. Current vaccines delay clinical signs but cannot train the immune system to fully eradicate latent Map. During latency, Map uses host defenses, cage-like macrophage clusters called granuloma, as incubators for months or years. We used an in vitro model to investigate the early coordination of macrophages into granuloma upon Map infection over ten days. We found that at multiplicities of infection (MOI; Map:macrophages) of 1:2 and below, the macrophages readily form clusters and evolve pro-inflammatory cytokines in keeping with a cell-mediated immune response. At higher MOIs, viability of host macrophages is negatively impacted. At 1:4 MOI, we quantified viable Map in our model and confirmed that intracellular Map reproduced over the first five days of infection. Host cells expressed Type 1-specific cytokines, and Map-infected macrophages displayed reduced motility compared to Map-exposed, uninfected macrophages, suggesting an important role for uninfected macrophages in the early aggregative response. Reported is the first in vitro JD granuloma model capturing Map and macrophage viability, size distribution of resulting clusters, motility of monocyte-derived macrophages, and cytokine response during clustering, allowing quantitative analysis of multiple parameters of the Map-specific granulomatous response.

scholarly journals Mycobacterium avium Subspecies paratuberculosis DNA and Antibodies in Dairy Goat Colostrum and Milk

2019 ◽  
Vol 6 (4) ◽  
pp. 96 ◽  
Author(s):  
Karianne Lievaart-Peterson ◽  
Saskia Luttikholt ◽  
Maaike Gonggrijp ◽  
Robin Ruuls ◽  
Lars Ravesloot ◽  
...  
Keyword(s):  
Mycobacterium Avium ◽  
Mycobacterium Avium Subspecies Paratuberculosis ◽  
Clinical Signs ◽  
Dairy Goat ◽  
Economic Losses ◽  
Dairy Goats ◽  
Convenience Sample ◽  
Milk Samples ◽  
Zoonotic Risk ◽  
Goat Population

Mycobacterium avium subspecies paratuberculosis (MAP) is endemic in the Dutch dairy goat population causing economic loss, and negatively influencing welfare. Moreover, there are concerns about a potential zoonotic risk. Therefore the industry’s objectives are to decrease MAP prevalence, limit economic losses as well as reduce the concentration of MAP in (bulk) milk. To diminish within-farm spread of infection, vaccination, age dependent group housing with separation of newborns from adults, as well as rearing on artificial or treated colostrum and milk replacers are implemented. However, the importance of MAP contaminated colostrum and milk as a route of infection in dairy goat herds is unknown. Therefore the aim of this study was to detect the presence of MAP DNA in colostrum and milk from dairy goats in infected herds. A convenience sample of 120 colostrum samples and 202 milk samples from MAP infected dairy goat herds were tested by IS900 real-time Polymerase Chain Reaction (PCR) for MAP DNA. Furthermore, 22 colostrum samples and 27 post mortem milk samples of goats with clinical signs consistent with paratuberculosis from known infected herds were tested. The majority of samples were from goats vaccinated against MAP. Positive or doubtful PCR results were obtained in none of the 120 and two of the 22 colostrum samples, and in eight of the 202 and four of the 27 milk samples Negative PCR results were obtained in the remaining 140 (99%) colostrum samples and 217 (95%) milk samples.

Sign in / Sign up

Export Citation Format

Share Document