158 PRINCIPLES AND PRACTICE OF MILK HYGIENE 



A thick cord-like induration, about the thickness of a lead 

 pencil, extending vertically through the middle of the teat, is a 

 symptom of catarrhal mastitis ; also nodular indurations in the 

 walls of the teat canal and milk cistern. Only slight alterations 

 may be present in the milk, or none at all. 



Atrophy is usually a symptom of an existing or previously 

 existing catarrhal mastitis. Milk from the affected quarter 

 may contain the organism responsible for the condition even 

 when it shows no perceptible changes. 



(For the changes in milk occurring during udder disease 

 see pages 105-110.) 



Firm, nodular swellings, not hot or painful, situated in the 

 superficial parts of the udder tissue, which are not movable and 

 which can be reduced by strong pressure, are retention cysts, 

 formed by the blocking of the milk ducts. 



(6) SPECIAL EXAMINATION 



The character of the special examination will depend 

 upon the information obtained during the general 

 examination. 



If fever is suspected the temperature should be taken 

 with a thermometer and an examination made for the 

 other symptoms of fever (chill; irregularity of the sur- 

 face temperature, especially of the extremities ; accelera- 

 ation of the pulse and respiration, loss of appetite, depres- 

 sion, albuminuria ) . In cattle the increase in temperature 

 as shown by the thermometer does not always correspond 

 to the degree of fever indicated by the other symptoms. 



When thoracic disease is suspected the chest wall 

 should be percussed. Areas of hepatization and solidifi- 

 cation may thus be discovered. The area of the lungs 

 of cattle which can be percussed is limited, however, and 

 unfortunately tubercular solidifications usually occur 

 below this area. Percussion may reveal painful condi- 

 tions of the lungs and pleura and may also produce 

 cough. 



