CHAPTER XI 

 GENERAL DISEASES : ORGANIC, FUNCTIONAL AND CONTAGIOUS * 



531. In this chapter we consider the commonest 

 diseases of the horse, with the general causes, 

 chief symptoms, and the best method of treat- 

 ment. I neither go into detail nor make mention 

 of uncommon diseases. The practice of experi- 

 menting with a horse is a dangerous one, and 

 therefore it is always advisable to call in pro- 

 fessional aid when anything serious is suspected. 

 It is a common practice amongst grooms and 

 others to " fill " a horse with patent drugs that in 

 most cases do more harm than good. The fewer 

 drugs kept in the stable the better. It is im- 

 possible to lay down hard and fast rules for the 

 treatment of any one disease, as different practi- 

 tioners use different methods, and the horse and 

 its surroundings vary so much as to necessitate 

 a variation in tlie details of treatment. 



The methods of treatment are those that have 

 met with the most success in the past few years, 

 but as new ideas and new drugs are being 

 brought forward every day, it is impossible to be 

 absolutely up to date in everything. The pro- 

 gress made in the manufacture of vaccines has 

 changed very considerably the treatment of many 

 infectious diseases. 



532. Temperature. — This is taken at the anus 

 by moistening the thermometer and inserting it 

 well in. A good thermometer registers in thirty 

 seconds ; it is safer, however, to leave it in for 

 one minute. Care must be taken to shake the 

 mercury down to about 96° before using the 

 thermometer ; this may be done by holding it 

 firmly in the hand and shaking it as if trying to 

 remove a drop of gum from the bulb. Always 

 wash the thermometer with an antiseptic before 

 putting it back in the case. The normal tempera- 

 ture is 100° F., or 38° C. ; in the human being 

 it is 98-4° F., or 37° C. 



The temperature of a mare may be one-half 

 to one degree Fahrenheit higher. Young horses 

 as a rule register a higher temperature than old 

 ones. The temperature is generally higher in 

 the evening and lower in the morning. During 

 work, during digestion, and while in a warm 

 atmosphere the temperature is higher. Cold 

 water or a cold atmosphere lowers the tempera- 

 ture [see Sees. 150-1). 



* For Surgical Diseases, see. Chapter IX. ; for Diseases of the 

 Foot, «ec Chapter XVIII. 



533. The Pulse. — The beats of the heart are 

 generally taken by pressing the first finger on the 

 submaxillary artery (glosso-facial), which passes 

 under the lower edge of the lower jaw bone, just 

 in front of the expanded portion at the angle of 

 this bone. (See P. 137.) The artery must be 

 lightly pressed just inside the hollow between 

 the rami of the lower jaw. At this point three 

 vessels pass under the bone, submaxillary artery 

 in front, submaxillary vein, and Steno's duct 

 from the parotid gland behind. The first finger 

 must be used in feeling the pulse. Normal pulse 

 is thirty-five to forty-five beats a minute. A wiry 

 pulse is one in which the artery is hard and 

 small, like a small wire. Normally, the pulse 

 should be fairly full and quite steady in its 

 action. 



Tlie Heart Sounds. — The cardiac sounds are 

 taken by holding the ear against the chest just 

 behind the elbow, with the leg held forward. A 

 stethoscope should be used, as it is difBcult to 

 hear the heart sounds distinctly with the naked 

 ear. The true sound is thus : Lubb-dupp-Lubb- 

 dupp. The first is a long, booming sound, due to 

 contraction of the ventricle and, simultaneously, 

 the vibrations of the auriculo-ventricular valves. 

 The second is a short sound, due to the sudden 

 closing of the large semi-lunar valves of the 

 arteries above the auricles (aortic and pulmonary 

 arteries). 



534. Respiration. — A horse breathes normally 

 when at rest at the rate of twelve to fifteen 

 respirations per minute. This is counted by 

 watching the horse's flanks. 



The murmur of the lungs is noticed by hold- 

 ing the ear, or, preferably, a stethoscope, against 

 the side of the horse's chest. The inspiration is 

 louder than the expiration. In some cases the 

 expiration can scarcely be heard. In horses that 

 are very fat it is difficult to hear the respiratory 

 murmur. In rare cases this murmur is undetect- 

 able for no apparent reason. The murmur is 

 produced by the friction of the air entering the 

 alveoli. The normal murmur is a soft, moist 

 purring sound, without any jerks or harshness. 

 It sounds like the noise made by the air coming 

 out from a pair of hand bellows when gently 

 blown. Near to the trachea at the entrance to 

 the lung can be heard the additional noise of the 



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