186 DISEASES OF THE FEET. 



seldom possible, except when the equine cargo is small as com- 

 pared to the size of the vessel. Inaction can also be a predisposing 

 cause, as the following paragraph shows. Laminitis sometimes 

 occurs from want of exercise on land, when horses are tied up in 

 stalls or boxes, owing to injury or disease, and are not allowed to 

 lie down ; and also when they refrain from lying down, owing to 

 the fact of their suffering from certain diseases, especially those of 

 the chest. Horses, under natural conditions, spend such a large 

 proportion of their time in almost constant movement, that the 

 usual long periods of enforced idleness in the stable have a very 

 deleterious effect on the soundness of the legs, by the consequent 

 congestion which is set up, particularly in their feet. 



2. Excessive work, especially at fast paces and on hard ground. 

 The amount of work capable of producing the disease, is propor- 

 tionate to the ability of the feet to bear it with impunity. Here 

 continued want of exercise has a particularly strong predisposing 

 efiect. Thus, horses which in ordinary working condition, could 

 trot for thirty miles on a hard road without any bad result, would 

 in all probability get laminitis, if walked, say, five miles imme- 

 diately on landing after a month's journey by sea ; provided they 

 had to stand up the whole time, and had had no exercise. Equally 

 bad effects would of course be produced under similar conditions 

 on land. Inattention to the predisposing influence which want of 

 exercise has in setting up laminitis, was the cause of many 

 thousands of landed horses being rendered unfit for service during 

 the late South African war. Laminitis brought on by excessive 

 work is much more intractable than laminitis due to all other 

 causes, except that of infection of the womb after foaling. 



3. Intestinal congestion, caused by indigestible food, severe pur- 

 gatives, etc. Purgatives like aloes and Epsom salts act by pro- 

 ducing congestion of the mucous membrane of the intestine, which 

 causes a discharge of watery fluid from that membrane into the 

 bowel, and consequent purging. When food is to blame in this 

 respect, it generally consists of wheat, barley, or maize given in 

 excessive quantities. ' 



i. Inflammation of the womb from foaling (septic metritis). 

 This form of the disease (parturient laminitis) very rarely occurs, 

 unless the foetal membranes (after birth) have been retained for at 

 least twelve hours, especially in heavy breeds, such as Shires ; and 

 light mares bear retention better than cart mares. Tisserant, 

 who, in 1846, was the first to note this particular form of laminitis, 

 stated that it generally occurs after abortion, or a difficult delivery. 

 It is an extremely dangerous variety of laminitis. 



5. Debilitating diseases, like influenza, particularly when they 

 weaken the action of the heart, predispose to laminitis. 



