A prebiotic, Celmanax™, decreases Escherichia coli O157:H7 colonization of bovine cells and feed-associated cytotoxicity in vitro

<p>Abstract</p> <p>Background</p> <p><it>Escherichia coli </it>O157:H7 is the most common serovar of enterohemorrhagic <it>E. coli </it>associated with serious human disease outbreaks. Cattle are the main reservoir with <it>E. coli </it>O157:H7 inducing hemorrhagic enteritis in persistent shedding beef cattle, however little is known about how this pathogen affects cattle health. Jejunal Hemorrhage Syndrome (JHS) has unclear etiology but the pathology is similar to that described for <it>E. coli </it>O157:H7 challenged beef cattle suggestive that <it>E. coli </it>O157:H7 could be involved. There are no effective treatments for JHS however new approaches to managing pathogen issues in livestock using prebiotics and probiotics are gaining support. The first objective of the current study was to characterize pathogen colonization in hemorrhaged jejunum of dairy cattle during natural JHS outbreaks. The second objective was to confirm the association of mycotoxigenic fungi in feeds with the development of JHS and also to identify the presence of potential mycotoxins. The third objective was to determine the impact of a prebiotic, Celmanax™, or probiotic, Dairyman's Choice™ paste, on the cytotoxicity associated with feed extracts <it>in vitro</it>. The fourth objective was to determine the impact of a prebiotic or a probiotic on <it>E. coli </it>O157:H7 colonization of mucosal explants and a bovine colonic cell line <it>in vitro</it>. The final objective was to determine if prebiotic and probiotic feed additives could modify the symptoms that preceded JHS losses and the development of new JHS cases.</p> <p>Findings</p> <p>Dairy cattle developed JHS after consuming feed containing several types of mycotoxigenic fungi including <it>Fusarium culmorum</it>, <it>F. poae</it>, <it>F. verticillioides</it>, <it>F. sporotrichioides</it>, <it>Aspergillus</it><it>flavus</it>, <it>Penicillium roqueforti, P. crustosum, P. paneum </it>and <it>P. citrinum</it>. Mixtures of Shiga toxin - producing <it>Escherichia coli </it>(STEC) colonized the mucosa in the hemorrhaged tissues of the cattle and no other pathogen was identified. The STECs expressed Stx1 and Stx2, but more significantly, Stxs were also present in the blood clot blocking the jejunum. Mycotoxin analysis of the corn crop confirmed the presence of fumonisin, NIV, ZEAR, DON, 15-ADON, 3-ADON, NEO, DAS, HT-2 and T-2. Feed extracts were toxic to enterocytes and 0.1% Celmanax™ removed the cytotoxicity <it>in vitro</it>. There was no effect of Dairyman's Choice™ paste on feed-extract activity <it>in vitro</it>. Fumonisin, T-2, ZEAR and DON were toxic to bovine cells and 0.1% Celmanax™ removed the cytotoxicity <it>in vitro</it>. Celmanax™ also directly decreased <it>E. coli </it>O157:H7 colonization of mucosal explants and a colonic cell line in a dose-dependent manner. There was no effect of Dairyman's Choice™ paste on <it>E. coli </it>O157:H7 colonization <it>in vitro</it>. The inclusion of the prebiotic and probiotic in the feed was associated with a decline in disease.</p> <p>Conclusion</p> <p>The current study confirmed an association between mycotoxigenic fungi in the feed and the development of JHS in cattle. This association was further expanded to include mycotoxins in the feed and mixtures of STECs colonizing the severely hemorrhaged tissues. Future studies should examine the extent of involvement of the different STEC in the infection process. The prebiotic, Celmanax™, acted as an anti-adhesive for STEC colonization and a mycotoxin binder <it>in vitro</it>. Future studies should determine the extent of involvement of the prebiotic in altering disease.</p

Fine Spatio-temporal Resolution Temperature and Humidity iButton Data at the Colorado State University Mountain Campus, August 25 to September 28, 2018

Seventeen iButton sensors were installed along an elevational transect from the top of a lateral moraine (2804 m.a.s.l.) on the west side of the Colorado State University Mountain Campus (CSU-MC) across the South Fork of the Cache la Poudre River (2745 ma.s.l.) to the base of the lateral moraine on the west side of the CSU-MC. This transect was approximately on the north side of the trail from the Homestead Bridge toward Sky Ranch. Twelve (T01 to T12) were thermochron iButton sensors that measured temperature only, with a 0.5°C temperature and 10-minute temporal resolution. Five (T21 to T25/ RH21 to RH25) were hygrochron iButton sensors that measured temperature at 0.0625°C and 20-minute resolution, and relative humidity at 0.04%RH and 20-minute resolution. All sensors were suspended by a fob in a double-set of ordinary white kitchen funnels employed as radiation shields. A medium (12.7 cm tall and 12 cm in diameter) funnel was placed inside a large (15.2 cm tall and 14 cm diameter) outside funnel. The inside funnel had about twelve 0.64 cm diameter holes drilled into it. Each shielded sensor was placed approximately 2-m above the ground on the north side of an evergreen trees. Data were downloaded every two weeks by removing the sensor from the fab and inserting into a USB dongle. Data measured during downloading were removed as temperatures warmed during handling (0.1% of the data). All missing and removed data were assigned values of -9999. One hygrochron was in an area that receives fog/excessive dew, and recorded relative humidity greater than 100% for 26 of the 1446 20-minute measurements. Locations are UTM coordinates in UTM 13N WGS84 datum obtained using a Garmin eTrex 10 Global Positioning System. The sensor elevation was extracted from National Elevation Dataset 10-m digital elevation model