MUCUS IN EQUINE LOWER AIRWAY DISEASE

How Should Excessive Mucus Accumulation in the Airways Be Interpreted?: When Is Excessive Mucus Accumulation Observed? In classical antiquity, respiration was thought to be a cooling mechanism for the blood, and nasal mucus a discharge from the brain. The credit of pointing out the pathophysiological significance of the mucous apparatus to Western medicine belongs to René Théophile Hyacinthe Laennec (1819): Excess respiratory secretions became recognized as one of the cardinal signs and central problems in many respiratory diseases of humans. Healthy respiratory epithelium is covered by a thin (5-20 microns) mucus layer. For the purpose of this paper any (endoscopically) visible mucus accumulation is defined as excessive. Although excessive airway secretions are a hallmark of recurrent airway obstruction (RAO or heaves) (Robinson et al., 1996; Workshop), they are a characteristic but non-specific sign, associated with inflammation in various equine airway diseases of both non-infectious and infectious origin (Dixon et al., 1995). The amount of the observed mucus varies greatly between individuals, and in order to determine its significance a way to reliably quantify respiratory secretions must be found.

[1]  C. Basbaum,et al.  Persistent mucin glycoprotein alterations in equine recurrent airway obstruction. , 2001, American journal of physiology. Lung cellular and molecular physiology.

[2]  M. King,et al.  Tracheobronchial mucus viscoelasticity during environmental challenge in horses with recurrent airway obstruction. , 2010, Equine veterinary journal.

[3]  M. Forni,et al.  In vitro mucolytic activity of recombinant human deoxyribonuclease on equine tracheobronchial mucus , 2000, Veterinary Record.

[4]  P. Taylor,et al.  Retrospective study of the relationships between age, inflammation and the isolation of bacteria from the lower respiratory tract of thoroughbred horses , 2000, Veterinary Record.

[5]  B. Rush,et al.  Pulmonary distribution of aerosolized technetium Tc 99m pentetate after administration of a single dose of aerosolized albuterol sulfate in horses with recurrent airway obstruction. , 1999, American journal of veterinary research.

[6]  M. Olszewski,et al.  The pathogenesis of chronic obstructivepulmonary disease of horses , 1996 .

[7]  D. Love,et al.  Effects of posture and accumulated airway secretions on tracheal mucociliary transport in the horse. , 1996, Australian veterinary journal.

[8]  M. Olszewski,et al.  The pathogenesis of chronic obstructive pulmonary disease of horses. , 1996, The British veterinary journal.

[9]  B. McGorum,et al.  Equine pulmonary disease: a case control study of 300 referred cases. Part 2: Details of animals and of historical and clinical findings. , 1995, Equine veterinary journal.

[10]  B. McGorum,et al.  Comparison of cellular and molecular components of bronchoalveolar lavage fluid harvested from different segments of the equine lung. , 1993, Research in veterinary science.

[11]  P. Dixon.  Respiratory mucociliary clearance in the horse in health and disease, and its pharmaceutical modification , 1992, Veterinary Record.

[12]  P. Gray,et al.  Increased pulmonary production of immunoreactive 15-hydroxyeicosatetraenoic acid in an animal model of asthma. , 1992, The American review of respiratory disease.

[13]  E. Nagy,et al.  The effects of equine rhinovirus, influenza virus and herpesvirus infection on tracheal clearance rate in horses. , 1992, Canadian journal of veterinary research = Revue canadienne de recherche veterinaire.

[14]  L. Riddolls,et al.  Use of scintigraphy for the determination of mucociliary clearance rates in normal, sedated, diseased and exercised horses. , 1991, Canadian journal of veterinary research = Revue canadienne de recherche veterinaire.

[15]  G. De Vico,et al.  Atypical cilia in the tracheal epithelium of healthy horses. , 1991, Journal of comparative pathology.

[16]  F. Kaup,et al.  Ultrastructural findings in horses with chronic obstructive pulmonary disease (COPD). I: Alterations of the larger conducting airways. , 1990, Equine veterinary journal.

[17]  C. Sweeney.  Tracheal mucus transport rate in healthy horses. , 1989, American journal of veterinary research.

[18]  N. E. Robinson,et al.  Effects of atropine in ponies with recurrent airway obstruction. , 1988, Journal of applied physiology.

[19]  Coombs Sl,et al.  Observations on tracheal mucociliary clearance in horses. , 1987 .

[20]  P. Webbon,et al.  Observations on tracheal mucociliary clearance in horses. , 1987, Tierarztliche Praxis. Supplement.

[21]  R. Schlesinger,et al.  Clearance from the respiratory tract. , 1985, Fundamental and applied toxicology : official journal of the Society of Toxicology.

[22]  U. Schatzmann,et al.  [Bronchial secretion aspiration in the horse]. , 1972, Schweizer Archiv fur Tierheilkunde.