PRINCIPLES OF VETERINARY SURGERY 17 



of regeneration. Connective tissue is prone to fill the spaces 

 not occupied by other cells, and this is a marked picture in 

 pathological processes. 



In pathological repair, the new tissue takes its origin 

 from the adjacent tissues of the same kind if the lesion is 

 slight; but in chronic abscesses and cases of severe wounds 

 and burns, etc., with extensive loss of substance, granula- 

 tions form which are ultimately replaced by cicatricial or con- 

 nective tissue. This imperfect partial regeneration forms a 

 scar. 



When the normal processes of repair are interfered with 

 by mechanical or chemical agents, or particularly by the in- 

 vasion of micro-organisms, an inflammatory process sets up. 

 The granular tissue by which repair was being effected at 

 once shows marked changes. If infiltrated with a serous or 



fibrinous fluid, then an exudative inflammation is the result; 



« 

 if leucocytes predominate, then it is a purulent inflammation. 



In all cases the pure healing process is stopped until the dis- 

 turbing cause is removed. 



DIRECT AND INDIRECT HEALING.— Every wound 

 heals by the formation of new tissue. If this is microscopic 

 in amount, as in a perfectly coaptated wound, direct or pri- 

 mary union is effected, and there remains no visible scar. 

 This is also known as healing by "first intention." Indirect 

 or secondary healing occurs in wounds which have suffered 

 an extensive loss of substance and therefore require the for- 

 mation of a large amount of new tissue. This can readily 

 be seen with the naked eye. In some cases it may be neces- 

 sary to hold in contact two granulating surfaces until they 

 fuse together, sometimes called healing by "third intention." 



SIMPLE REPARATIVE PROCESSES. 



The pathological conditions to be repaired usually consist 

 of wounds, infections, or some organic lesion; and the repar- 



