Detection of macrocyclic trichothecene mycotoxin in a caprine (goat) tracheal instillation model.

This study demonstrates the detection and dynamics of macrocyclic trichothecene mycotoxin (MTM) tissue loading using a commercially available assay in a goat model. The detection of MTMs has been difficult and complex due to the uncertainty of what tissues to examine and when to sample. Twelve goats (two groups of each) were instilled with Stachybotrys chartarum conidial suspension via the trachea.

Effects of inhaled fine dust on lung tissue changes and antibody response induced by spores of opportunistic fungi in goats.

Objective: To investigate the effects of sterile fine dust aerosol inhalation on antibody responses and lung tissue changes induced by Mucor ramosissimus or Trichoderma viride spores following intratracheal inoculation in goats.

Animals: 36 weanling Boer-Spanish goats.

Procedures: 6 goats were allocated to each of 2 M ramosissimus-inoculated groups, 2 T viride-inoculated groups, and 2 control (tent or pen) groups.

Effects of aerosolized feedyard dust that contains natural endotoxins on adult sheep.

Objective: To determine the clinical, clinicopathologic, and histologic effects of aerosolized feedyard dust that contains natural endotoxins on adult sheep.

Animals: Eighteen 3-year-old Saint Croix sheep.

Procedure: A prospective randomized controlled study was conducted.

Effects of aerosolized class C fly ash in weanling goats.

Objective: To determine effects of repeated aerosol exposures to fly ash dust on respiratory tracts of tent-confined goats.

Animals: 12 weanling Boer-Spanish crossbred goats.

Procedure: Goats were randomly assigned to 2 groups: fly ash treatment group (principal goats, n = 6) or control group (control goats, 6).

Virulence of fungal spores determined by tracheal inoculation of goats following inhalation of aerosolized sterile feedyard dust.

Objective: To compare the virulence of spores of 7 fungi by tracheal inoculation of goats following exposure of goats to an aerosol of sterilized feedyard dust. Animals-54 weanling Boer-Spanish goats.

Procedure: A prospective randomized controlled study was conducted.

Effect of transport stress on respiratory disease, serum antioxidant status, and serum concentrations of lipid peroxidation biomarkers in beef cattle.

Objective: To determine the effect of transportation stress on serum concentrations of oxidative stress biomarkers of calves.

Animals: 105 crossbred beef steer calves (mean [+/-SD] body weight, 207 +/- 21.2 kg).

Comparison of the type and number of microorganisms and concentration of endotoxin in the air of feedyards in the Southern High Plains.

Objectives: To determine the bacterial, fungal, and endotoxin concentrations in aerosolized ambient air during the winter and summer in feedyards located in the Southern High Plains, identify aerosolized microbial pathogens, and determine the size of microbial and dust components.

Sample Population: Aerosol samples were obtained from 7 feedyards.

Procedure: Aerosol samples were collected upwind, on-site, and downwind from each feedyard at a point 1 m above the ground by use of biological 2- and 6-stage cascade impactors.

Diversity of Salmonella serovars in feedyard and nonfeedyard playas of the Southern High Plains in the summer and winter.

Objective: To compare Salmonella isolates cultured from feedyard and nonfeedyard (control) playas (ie, temporary shallow lakes) of the Southern High Plains.

Sample Population: Water and muck (sediment) samples were obtained from 7 feedyard playas and 3 nonfeedyard playas in the winter and summer.

Procedure: Each water and muck sample was enriched with sulfur-brilliant-green broth and incubated in a shaker at 37 degrees C for 24 hours.

Effects of aerosolized dust in goats on lung clearance of Pasteurella and Mannheimia species.

The objective was to determine whether the inhalation of large quantities of feedyard dust predisposed the animals to pulmonary bacterial proliferation. Two control groups, C1 and C2, did not receive dust treatments, and two principal groups (P1 and P2) received a total of 14 dust treatments each. The C1 and P1 groups of goats each received a transthoracic challenge of live Mannheimia haemolytica (4 x 10(6) colony forming units, CFU) The C2 and P2 groups of goats each received a transthoracic challenge of live Pasteurella multocida (1.

Bovine adenovirus serotype 7 infections in postweaning calves.

Objective: To detect bovine adenovirus serotype 7 (BAV-7) infections in calves by use of viral isolation and serologic testing.

Animals: 205 postweaning calves.

Procedure: 121 calves were assembled by an order buyer through auction markets in eastern Tennessee and transported to New Mexico where they were commingled with 84 healthy ranch-reared calves.

Effects of vaccination prior to transit and administration of florfenicol at time of arrival in a feedlot on the health of transported calves and detection of Mannheimia haemolytica in nasal secretions.

Objective: To determine effects of vaccination prior to transit and prophylactic administration of florfenicol at time of arrival at a feedyard on health of cattle and colonization of the nasopharynx by Mannheimia haemolytica (MH).

Animals: 121 steers from Tennessee and 84 steers from New Mexico.

Procedure: Half of the steers were vaccinated before transport to a feedyard.