scholarly journals Effects of Ammonia Inhalation and Acetic Acid Pretreatment on Colonization Kinetics of Toxigenic Pasteurella multocida within Upper Respiratory Tracts of Swine

1998 ◽  
Vol 36 (5) ◽  
pp. 1260-1265 ◽  
Author(s):  
T. D. C. Hamilton ◽  
J. M. Roe ◽  
C. M. Hayes ◽  
A. J. F. Webster
Keyword(s):  
Acetic Acid ◽  
Respiratory Tract ◽  
Nasal Cavity ◽  
Pasteurella Multocida ◽  
Atrophic Rhinitis ◽  
Upper Respiratory Tract ◽  
Acid Pretreatment ◽  
Morphometric Index ◽  
Upper Respiratory ◽  
Kinetics Of

Pigs reared in intensive production systems are continuously exposed to ammonia released by the microbial degradation of their excrement. Exposure to this gas has been shown to increase the severity of the disease progressive atrophic rhinitis by facilitating colonization of the pig’s upper respiratory tract by Pasteurella multocida. The etiological mechanism responsible for this synergy was investigated by studying the colonization kinetics of P. multocida enhanced by ammonia and comparing them with those evoked by an established disease model. Three-week-old Large White piglets were weaned and allocated to five experimental groups (groups A to E). Pigs in groups A and B were exposed continuously to ammonia at 20 ppm for the first 2 weeks of the study. Pigs in group C were pretreated with 0.5 ml of 1% acetic acid per nostril on days −2 and −1 of the study. On day 0 all the pigs in groups A, C, and D were inoculated with 1.4 × 108 toxigenic P. multocida organisms given by the intranasal route. The kinetics of P. multocida colonization were established by testing samples obtained at weekly intervals throughout the study. The study was terminated on day 37, and the extent of turbinate atrophy was determined by using a morphometric index. The results of the study showed that exposure to aerial ammonia for a limited period had a marked effect on the colonization of toxigenic P. multocidain the nasal cavities of pigs, which resulted in the almost total exclusion of commensal flora. In contrast, ammonia had only a limited effect on P. multocida colonization at the tonsil. The exacerbation of P. multocida colonization by ammonia was restricted to the period of ammonia exposure, and the number ofP. multocida organisms colonizing the upper respiratory tract declined rapidly upon the cessation of exposure to ammonia. During the exposure period, the ammonia levels in mucus recovered from the nasal cavity and tonsil were found to be 7- and 3.5-fold higher, respectively, than the levels in samples taken from unexposed controls. Acetic acid pretreatment also induced marked colonization of the nasal cavity which, in contrast to that induced by ammonia, persisted throughout the time course of the study. Furthermore, acetic acid pretreatment induced marked but transient colonization of the tonsil. These findings suggest that the synergistic effect of ammonia acts through an etiological mechanism different from that evoked by acetic acid pretreatment. A strong correlation was found between the numbers of P. multocida organisms isolated from the nasal cavity and the severity of clinical lesions, as determined by using a morphometric index. The data presented in the paper highlight the potential importance of ammonia as an exacerbating factor in respiratory disease of intensively reared livestock.

scholarly journals Contributory and Exacerbating Roles of Gaseous Ammonia and Organic Dust in the Etiology of Atrophic Rhinitis

1999 ◽  
Vol 6 (2) ◽  
pp. 199-203 ◽  
Author(s):  
T. D. C. Hamilton ◽  
J. M. Roe ◽  
C. M. Hayes ◽  
P. Jones ◽  
G. R. Pearson ◽  
...  
Keyword(s):  
Respiratory Tract ◽  
Pasteurella Multocida ◽  
Exposure Period ◽  
Gaseous Ammonia ◽  
Atrophic Rhinitis ◽  
Upper Respiratory Tract ◽  
Large White ◽  
Type D ◽  
Epidemiological Surveys ◽  
Upper Respiratory

ABSTRACT Pigs reared commercially indoors are exposed to air heavily contaminated with particulate and gaseous pollutants. Epidemiological surveys have shown an association between the levels of these pollutants and the severity of lesions associated with the upper respiratory tract disease of swine atrophic rhinitis. This study investigated the role of aerial pollutants in the etiology of atrophic rhinitis induced by Pasteurella multocida. Forty, 1-week-old Large White piglets were weaned and divided into eight groups designated A to H. The groups were housed in Rochester exposure chambers and continuously exposed to the following pollutants: ovalbumin (groups A and B), ammonia (groups C and D), ovalbumin plus ammonia (groups E and F), and unpolluted air (groups G and H). The concentrations of pollutants used were 20 mg m−3 total mass and 5 mg m−3 respirable mass for ovalbumin dust and 50 ppm for ammonia. One week after exposure commenced, the pigs in groups A, C, E, and G were infected with P. multocida type D by intranasal inoculation. After 4 weeks of exposure to pollutants, the pigs were killed and the extent of turbinate atrophy was assessed with a morphometric index (MI). Control pigs kept in clean air and not inoculated with P. multocida (group H) had normal turbinate morphology with a mean MI of 41.12% (standard deviation [SD], ± 1.59%). In contrast, exposure to pollutants in the absence of P. multocida (groups B, D, and F) induced mild turbinate atrophy with mean MIs of 49.65% (SD, ±1.96%), 51.04% (SD, ±2.06%), and 49.88% (SD, ±3.51%), respectively. A similar level of atrophy was also evoked by inoculation with P. multocida in the absence of pollutants (group G), giving a mean MI of 50.77% (SD, ±2.07%). However, when P. multocida inoculation was combined with pollutant exposure (groups A, C, and E) moderate to severe turbinate atrophy occurred with mean MIs of 64.93% (SD, ±4.64%), 59.18% (SD, ±2.79%), and 73.30% (SD, ±3.19%), respectively. The severity of atrophy was greatest in pigs exposed simultaneously to dust and ammonia. At the end of the exposure period, higher numbers of P. multocida bacteria were isolated from the tonsils than from the nasal membrane, per gram of tissue. The severity of turbinate atrophy in inoculated pigs was proportional to the number of P. multocida bacteria isolated from tonsils (r 2 = 0.909, P < 0.05) and nasal membrane (r 2 = 0.628, P< 0.05). These findings indicate that aerial pollutants contribute to the severity of lesions associated with atrophic rhinitis by facilitating colonization of the pig’s upper respiratory tract byP. multocida and also by directly evoking mild atrophy.

Atrophic rhinitis: the influence of the aerial environment

1990 ◽  
Vol 50 (1) ◽  
pp. 173-182 ◽  
Author(s):  
J. F. Robertson ◽  
D. Wilson ◽  
W. J. Smith
Keyword(s):  
Respiratory Tract ◽  
Pasteurella Multocida ◽  
Stocking Density ◽  
Atrophic Rhinitis ◽  
Upper Respiratory Tract ◽  
Live Animal ◽  
Large Numbers ◽  
Viable Bacteria ◽  
Upper Respiratory ◽  
Severity Of The Disease

ABSTRACTInfectious atrophic rhinitis is a disease of the upper respiratory tract of pigs, characterized in the live animal by deformation of the snout and conchal atrophy. However, the severity of the disease in pigs on commercial units is highly variable and air quality may be implicated as a significant factor in addition to the recognized pathogens. In this study the aerial environment was monitored in 49 pig buildings on 12 commercial farrowing-finishing units. A total of 1117 pigs from the 12 farms were examined individually at commercial slaughter weight to quantify the severity of conchal atrophy, using snout scoring and morphometric techniques.A number of significant relationships were shown between environmental variables in the farrowing house and the severity of conchal atrophy. Mean snout score (MSS) and the percentage of snouts from each herd sample with a score of three or more (SS3) were correlated with total bacterial counts (r = 0·78 (P < 0·01) and 0-83 (P < 0·01) respectively), counts of 10 [mi to >15 urn particles (r = 0·67 (P <0·05), 0·73 (P <0·05)) and concentrations of gravimetric dust (r = 0·65 (P <0·05), 0·64 (P <0·05)). Concentrations of ammonia were correlated with SS3 (r = 0·68 (P <0·05)).Dust in the first-stage weaner houses was again a significant component of the aerial environment associated with the severity of the disease. MSS and SS3 were correlated with counts of 10 urn to >15 μm particles (r = 0·66 (P <0·05), 0·68 (P <0·05)), concentrations of respirable dust (r = 0·67 (P <0·05), 0·63 (P <0·05)), total dust (r = 0·75 (P <0·05), 0·87 (P <0·001)), and gravimetric dust (r = 0·83 (P <0·01), 0·88 (P <0·001)). The results support the theory that the mass or number of particles present as inspirable aerosols, and the presence of large numbers of viable bacteria may compromise the local defence mechanism of the upper respiratory tract in the pig and facilitate colonization by Bordetella bronchiseptica and Pasteurella multocida. Saturation deficit in the second-stage weaner houses was correlated with both mean morphometric index and SS3 (r = 0·860 (P <0·01) and 0·683 (P <0·05) respectively), and volumetric stocking density in the finishing houses was correlated with both MSS and SS3 (r = -0·84 (P <0·01), -0·64 (P <0·05)). It is hypothesized that the severity of the disease may be lessened by reducing the concentrations of dust, microbes and ammonia which may play a significant role in the development of the disease.

scholarly journals Effect of Ovalbumin Aerosol Exposure on Colonization of the Porcine Upper Airway by Pasteurella multocida and Effect of Colonization on Subsequent Immune Function

1998 ◽  
Vol 5 (4) ◽  
pp. 494-498 ◽  
Author(s):  
T. D. C. Hamilton ◽  
J. M. Roe ◽  
C. M. Hayes ◽  
A. J. F. Webster
Keyword(s):  
Pasteurella Multocida ◽  
Upper Airway ◽  
Respiratory Pathogen ◽  
Atrophic Rhinitis ◽  
Upper Respiratory Tract ◽  
Aerosol Exposure ◽  
Morphometric Index ◽  
Upper Respiratory ◽  
Dose Dependent Increase ◽  
Dose Dependent

ABSTRACT Seventy-three piglets were weaned at 1 week of age, randomly assigned to 10 groups (A to J), accommodated in stainless steel exposure chambers, and exposed continuously to a controlled environment containing aerosolized ovalbumin. The concentrations of ovalbumin dust were as follows (milligrams per cubic meter): A and F, 16.6; B and G, 8.4; C and H, 4.2; D and I, 2.1; E and J, 0. At weekly intervals, the pigs were bled via venipuncture and anesthetized for nasal lavage and tonsilar biopsies performed for subsequent bacteriologic analysis. At 2 weeks of age, the pigs in groups A to E were challenged with toxigenicPasteurella multocida (108 CFU pig−1), and at 6 weeks of age, the pigs were euthanatized. At postmortem, the extent of turbinate atrophy was assessed on the snout sections by using a morphometric index. Exposure to aerial ovalbumin resulted in a dose-dependent increase in serum antiovalbumin immunoglobulin G (IgG; P < 0.001) and serum antiovalbumin IgA (P < 0.001). Exposure also caused a significant increase in the numbers of P. multocidaorganisms isolated from the upper respiratory tract (P< 0.001) and a corresponding increase in turbinate atrophy, as judged by the morphometric index (P < 0.001). Concurrent challenge with P. multocida and ovalbumin resulted in a significant decrease in both the IgG and IgA responses to ovalbumin (P < 0.001). These results show that ovalbumin exposure increases pig susceptibility to P. multocidacolonization and that toxigenic P. multocida modifies the serum IgG and IgA responses to ovalbumin in the pig. Both of these effects may enhance the virulence of this respiratory pathogen and so influence the pathogenesis of atrophic rhinitis in pigs.

Changes in the parameters of nasal breathing and parameters of the upper respiratory tract during orthognathic operations in patients with II and III skeletal class of jaw anomalies

2020 ◽  
pp. 22-27
Author(s):  
S.Sh. Gammadaeva ◽  
M.I. Misirkhanova ◽  
A.Yu. Drobyshev
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Nasal Septum ◽  
Cross Sectional Area ◽  
Upper Respiratory Tract ◽  
Sectional Area ◽  
Nasal Breathing ◽  
Cross Sectional ◽  
Skeletal Class ◽  
Upper Respiratory

The study analyzed the functional parameters of nasal breathing, linear parameters of the nasal aperture, nasal cavity and nasopharynx, volumetric parameters of the upper airways in patients with II and III skeletal class of jaw anomalies before and after orthognathic surgery. The respiratory function of the nose was assessed using a rhinomanometric complex. According to rhinoresistometry data, nasal resistance and hydraulic diameter were assessed. According to the data of acoustic rhinometry, the minimum cross-sectional area along the internal valve, the minimum cross-sectional area on the head of the inferior turbinate and nasal septum and related parameters were estimated. According to the CBCT data, the state of the nasal septum, the inferior turbinates, the nasal aperture, the state of the nasal cavity, and the linear values of the upper respiratory tract (nasopharynx) were analyzed. The patients were divided into 4 groups according to the classification of the patency of the nasal passages by

Photography and the flexible fibreoptic rhinolaryngoscope

1986 ◽  
Vol 100 (1) ◽  
pp. 41-46 ◽  
Author(s):  
J. M. Lancer
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Upper Respiratory Tract ◽  
Pathological Anatomy ◽  
Medical Practitioners ◽  
Upper Respiratory

SummaryDocumentation of normal and pathological anatomy is important to all medical practitioners. The ability to visualize and photograph the upper respiratory tract has been revolutionized by the advent of the flexible fibreoptic rhinolaryngoscope (FFRL), which demonstrates a one-instrument capability for the examination and photodocumentation of the ears, nasal cavity, nasopharynx, larynx, hypopharynx and trachea (Selkin, 1984). If a large natural maxillary ostium, or surgical window, is present, the antrum may also be examined.

scholarly journals Kinetics of BoHV-1 Dissemination in an in Vitro Culture of Bovine Upper Respiratory Tract Mucosa Explants

ILAR Journal ◽  
2012 ◽  
Vol 53 (1) ◽  
pp. E43-E54 ◽  
Author(s):  
L. Steukers ◽  
A. P. Vandekerckhove ◽  
W. Van den Broeck ◽  
S. Glorieux ◽  
H. J. Nauwynck
Keyword(s):  
Respiratory Tract ◽  
In Vitro Culture ◽  
Upper Respiratory Tract ◽  
Upper Respiratory ◽  
Kinetics Of

scholarly journals Asymptomatic COVID-19 Adult Outpatients identified as Significant Viable SARS-CoV-2 Shedders 

2021 ◽  
Author(s):  
Marie Glenet ◽  
Anne-Laure Lebreil ◽  
Laetitia Heng ◽  
Yohan N’Guyen ◽  
Ittah Meyer ◽  
...  
Keyword(s):  
Respiratory Tract ◽  
Control Measures ◽  
Upper Respiratory Tract ◽  
Rna Detection ◽  
Viral Loads ◽  
Infection Control Measures ◽  
Infected Adult ◽  
Asymptomatic Adult ◽  
Upper Respiratory ◽  
Kinetics Of

Abstract Differential kinetics of RNA loads and infectious viral levels in the upper respiratory tract between asymptomatic and symptomatic SARS-CoV-2 infected adult outpatients remain unclear limiting recommendations that may guide clinical management, infection control measures and occupational health decisions. In the present investigation, 496 (2.5%) of 17,911 French adult outpatients were positive for an upper respiratory tract SARS-CoV-2 RNA detection by a quantitative RT-PCR assay, of which 180 (36.3%) were COVID-19 asymptomatic. Of these adult asymptomatic viral shedders, 84.4% had mean to high RNA viral loads (Ct values<30) which median value was significantly higher than that observed in symptomatic subjects (P=0.029), and 50.6% were positive by cell culture assays of their upper respiratory tract specimens. Our findings indicate that COVID-19 asymptomatic adult outpatients are significant viable SARS-CoV-2 shedders in their upper respiratory tract playing a major potential role as SARS-CoV-2 transmitters in various epidemiological transmission chains, promoting COVID-19 resurgence in populations.

scholarly journals Preventive and therapeutic role of nasal irrigation in management of acute respiratory disease during COVID-19 pandemic and beyond

2021 ◽  
pp. 58-64
Author(s):  
V. M. Svistushkin ◽  
Zh. T. Mokoyan
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Distribution Area ◽  
Upper Respiratory Tract ◽  
Saline Irrigation ◽  
Nasal Irrigation ◽  
Wide Range ◽  
Upper Respiratory ◽  
Nasal Saline Irrigation ◽  
Tract Infections

It has long been known, that nasal saline irrigation is a safe and effective method, which is routinely prescribed by otorhinolaryngologists to prevent and to treat a wide range of pathologies. There are a lot of publications on different irrigation techniques and methods. This literature review discusses the key parameters of nasal irrigation, including tonicity, pH, and the additional components, and explains how they affect the effectiveness of the procedure. The vast majority of available publications did not found any possible changes in the effectiveness of solutions with different pH close to neutral meaning. Whereas, the volume of the irrigated solution, increases the efficiency of the irrigation in direct proportion. Thus, the largest distribution area of the solute is noted when washing with a large volume of liquid. Nasal saline irrigation is an effective treatment option for patients with several acute and chronic diseases and for postoperative care after rhinosurgery. Moreover, nasal irrigation might be used as an effective non-specific method for prevention of acute upper respiratory tract infections. Irrigation of the nasal cavity reduces the mucus viscosity and promotes its faster elimination, along with pathogens fixed in it. Additionally, irrigation with isotonic saline solutions increases the hydration of the underlying water base, which enhances the frequency of ciliary beat and reduces the concentration of local inflammatory mediators. COVID-19 pandemic situation due to lack of any specific antiviral drugs dictates the necessity of an effective non-specific preventive option, which could be introduced worldwide. The so-called full volume lavage of the nasal cavity allows for better cleaning of the nasal cavity and effective moisturizing of the mucous membrane. It is the timely cleansing and moisturizing that are most important for maintaining the normal activity of the local protective mechanisms of the upper respiratory tract.

scholarly journals Role of the Dermonecrotic Toxin of Bordetella bronchiseptica in the Pathogenesis of Respiratory Disease in Swine

2002 ◽  
Vol 70 (2) ◽  
pp. 481-490 ◽  
Author(s):  
Susan L. Brockmeier ◽  
Karen B. Register ◽  
Tibor Magyar ◽  
Alistair J. Lax ◽  
Gillian D. Pullinger ◽  
...  
Keyword(s):  
Respiratory Tract ◽  
Respiratory Disease ◽  
Bordetella Bronchiseptica ◽  
Atrophic Rhinitis ◽  
Upper Respiratory Tract ◽  
Dermonecrotic Toxin ◽  
Etiologic Agents ◽  
Upper Respiratory ◽  
Phosphate Buffered Saline

ABSTRACT Bordetella bronchiseptica is one of the etiologic agents causing atrophic rhinitis and pneumonia in swine. It produces several purported virulence factors, including the dermonecrotic toxin (DNT), which has been implicated in the turbinate atrophy seen in cases of atrophic rhinitis. The purpose of these experiments was to clarify the role of this toxin in respiratory disease by comparing the pathogenicity in swine of two isogenic dnt mutants to their virulent DNT+ parent strains. Two separate experiments were performed, one with each of the mutant-parent pairs. One-week-old cesarean-derived, colostrum-deprived pigs were inoculated intranasally with the parent strain, the dnt mutant strain, or phosphate-buffered saline. Weekly nasal washes were performed to monitor colonization of the nasal cavity, and the pigs were euthanized 4 weeks after inoculation to determine colonization of tissues and to examine the respiratory tract for pathology. There was evidence that colonization of the upper respiratory tract, but not the lower respiratory tract, was slightly greater for the parent strains than for the dnt mutants. Moderate turbinate atrophy and bronchopneumonia were found in most pigs given the parent strains, while there was no turbinate atrophy or pneumonia in pigs challenged with the dnt mutant strains. Therefore, production of DNT by B. bronchiseptica is necessary to produce the lesions of turbinate atrophy and bronchopneumonia in pigs infected with this organism.

Measurement of Local Mass Transfer Coefficients in a Cast Model of the Human Upper Respiratory Tract

1986 ◽  
Vol 108 (1) ◽  
pp. 12-18 ◽  
Author(s):  
L. M. Hanna ◽  
P. W. Scherer
Keyword(s):  
Mass Transfer ◽  
Respiratory Tract ◽  
Nasal Cavity ◽  
Upper Respiratory Tract ◽  
Transfer Coefficients ◽  
Mass Transfer Coefficients ◽  
Local Mass ◽  
Local Mass Transfer ◽  
Cast Model ◽  
Upper Respiratory

Local mass transfer coefficients measured using the naphthalene sublimation technique in an acrylic cast model of the human upper respiratory tract are reported as the Sherwood numbers for the corresponding regions. A steady air flow rate of 12 L per min was used for all measurements. Values of the Sherwood number are seen to be highest in the nasal cavity and proximal nasopharynx while a minimum value occurs just downstream from the larynx. Local values of the Nusselt number obtained in the trachea and proximal nasal cavity assuming a complete heat and mass transfer analogy agree well with in-vivo physiological measurements. The mass transfer coefficients found can be incorporated into an analytical model of respiratory heat and water vapor transfer or into a model of pollutant gas uptake in the respiratory tract.

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