Effects of Aerosolized Dust in Goats on Lung Clearance of Pasteurella and Mannheimia Species

Abstract

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 (1.0 x 10(6) CFU/goat). The results showed that dusted animals had fever when compared with non-dusted controls. In addition, dusted animals demonstrated a leukocytosis with neutrophilia after the first dust treatment that was not sustainable. Finally, dusted animals demonstrated pulmonary clearance of two potential bacterial pathogens that was not significantly different from that shown by control (not dusted) animals.

Feedlot Acute Interstitial Pneumonia

“…Perhaps hot or dusty weather simply puts the respiratory system under more pressure when it is already primed for AIP by 1 or more of the factors listed previously, pushing more cattle to a tipping point that leads to disease. Exposure of sheep or goats to repeated doses of aerosolized feedlot dust containing microorganisms and endotoxin did not lead to AIP, 24,25 and exposure to M haemolytica or P multocida did not induce serious lung disease in goats exposed to aerosolized feedlot dust. 25 Moreover, tracheal instillation of spores of fungi commonly found in feedlot dust did not induce AIP in goats.…”

“…Exposure of sheep or goats to repeated doses of aerosolized feedlot dust containing microorganisms and endotoxin did not lead to AIP, 24,25 and exposure to M haemolytica or P multocida did not induce serious lung disease in goats exposed to aerosolized feedlot dust. 25 Moreover, tracheal instillation of spores of fungi commonly found in feedlot dust did not induce AIP in goats. 26 These studies suggest that feedlot dust exposure alone is unlikely to cause AIP.…”

Bovine respiratory disease associated with Histophilus somni and bovine respiratory syncytial virus in a beef cattle feedlot from Southeastern Brazil

“…However, an experimental study did not demonstrate differences in pulmonary disease in cattle that were exposed or relative to those not exposed to dust particles (PURDY et al, 2003).Consequently, the climatic conditions during the dry dusty period might per se not have any direct effect on the development of BRD observed during this investigation, but when coupled with concomitant infectious pathogens, management and genetic factors can have an impact on the pathogenesis of BRD (TAYLOR et al, 2010). However, it must be highlighted that the onset of respiratory disease began long after the affected animals were conditioned within the feedlot, and not within the first few days/weeks on feed as is frequently described in BRD from North America (RIBBLE et al, 1995;GAGEA et al, 2006).…”

Evaluation of tulathromycin as an antimicrobial therapy in the caprine species

“…Bacterial respiratory disease is a common health concern in small ruminants with potential life-threatening consequences Martin, 2010;. The most frequently implicated bacterial agents in this disease complex are Mannheimia haemolytica, Pasteurella multocida, and Bibersteinia (Pasteurella) trehalosi, often complicated by Mycoplasma species Alley et al, 1999;Rahman & Singh, 1990;Shayegh et al, 2009; Murphy et al, 2010;Purdy et al, 2003;Yener et al, 2005). More importantly, these agents damage host defenses and predispose the lung to bacterial entry into lungs.…”

“…Stress associated with weather extremes, weaning, transport, and poor nutrition have all been implicated as predisposing factors associated with the development of pneumonia Purdy et al, 2003;Shafarin et al, 2009). M. haemolytica, P. multocida, and B.…”