Fermentation Products That Mitigate Foodborne in Cattle and Poultry.

Prior studies revealed that yeast fermentation products, specifically XPC™ and related products (Diamond V, Cedar Rapids, IA), serve as viable food safety tools across multiple food animal species including cattle and poultry. Providing this supplement in feed leads to reduced prevalence, load, virulence, and antibiotic resistance of foodborne pathogens such as and O157:H7. These findings are worthy of further study, especially when coupled with the enhanced growth and performance observed with these products.

Doxycycline as an inhibitor of p-glycoprotein in the alpaca for the purpose of maintaining avermectins in the CNS during treatment for parelaphostrongylosis.

Meningeal worms (Parelaphostrongylus tenuis) are a common malady of alpacas, often refractory to conventional treatments. Ivermectin is a very effective anthelmintic used against a variety of parasites but this drug is not consistently effective against alpaca meningeal worms once the parasite has gained access to the CNS, even if used in a protracted treatment protocol. Ivermectin is not effective against clinical cases of P.

Amelioration of salmonellosis in pre-weaned dairy calves fed Saccharomyces cerevisiae fermentation products in feed and milk replacer.

Salmonellosis is an insidious and potentially epidemic problem in pre-weaned dairy calves. Managing this disease, or any other diarrheal disease, is a financial burden to producers. Calf mortalities and medicinal treatments are overt costs of salmonellosis, while hidden costs include hampered weight gains and persistent intestinal colonization of the pathogen.

Effects of subtherapeutic concentrations of antimicrobials on gene acquisition events in Yersinia, Proteus, Shigella, and Salmonella recipient organisms in isolated ligated intestinal loops of swine.

Objective: To assess antimicrobial resistance and transfer of virulence genes facilitated by subtherapeutic concentrations of antimicrobials in swine intestines.

Animals: 20 anesthetized pigs experimentally inoculated with donor and recipient bacteria.

Procedures: 4 recipient pathogenic bacteria (Salmonella enterica serotype Typhimurium, Yersinia enterocolitica, Shigella flexneri, or Proteus mirabilis) were incubated with donor bacteria in the presence of subinhibitory concentrations of 1 of 16 antimicrobials in isolated ligated intestinal loops in swine.

Beta-lactam antibiotics prevent Salmonella-mediated bovine encephalopathy regardless of the β-lactam resistance status of the bacteria.

This study assessed the capacity of β-lactam antibiotics to prevent salmonella-mediated encephalopathy in calves given the putative neuroprotective effects of these drugs of increasing glutamate export from the brain. Both ampicillin and ceftiofur prevented the development of encephalopathy despite resistance of the inoculated Salmonella enterica serovar Saint-Paul isolate to both drugs. A glutamate receptor antagonist also prevented this salmonella-mediated encephalopathy.

Expression of a collagenase that enables blood-brain barrier penetration for Salmonella implicated in bovine encephalopathies.

Recent studies identified strains of Salmonella that induce encephalopathies in calves exposed to stressful situations. In order to cause neurologic signs (such as ataxia, head tilt, and partial blindness), the strain must be able to cross the blood-brain barrier (BBB). One possible way is through the break down of tight junctions, which regulate the permeability of the BBB and can be weakened by enzymes such as collagenases.

Comparisons of Salmonella conjugation and virulence gene hyperexpression mediated by rumen protozoa from domestic and exotic ruminants.

Recent studies have identified a phenomenon in which ciliated protozoa engulf Salmonella and the intra-protozoal environment hyperactivates virulence gene expression and provides a venue for conjugal transfer of antibiotic resistance plasmids. The former observation is relegated to Salmonella bearing the SGI1 multiresistance integron while the latter phenomenon appears to be a more generalized event for recipient Salmonella. Our previous studies have assessed virulence gene hyperexpression only with protozoa from the bovine rumen while conjugal transfer has been demonstrated in rumen protozoa from cattle and goats.