No. 7. 



Bots. 



223 



Bots. 



Of all the insects that irritate and injure 

 tliat noble animal the Horso, there is none 

 pcrliaps more vexatious or more pernicious, 

 in all its stages of existence, than the Bot. 

 Its parent, the Horse or Gad-fly of the farmer, 

 the QDstrus Equi of the veterinarian, is com- 

 mon in the autumn, and it is tlien that the 

 mischief which is performed by its method of 

 perpetuating its species, is usually accom- 

 plished. The bot itself is the larva; or catter- 

 pillar of the fly, and the manner of its intro- 

 duction into the stomach of the horse, where 

 it is to prepare for its final transformation, is 

 a curious illustration of the means provided 

 the insect to eflect the end designed. 



The male of the gad-fly is rarely observed, 

 but the female, during the season it occupies 

 in depositing its eggs, may be seen, with the 

 extremity of its body turned under and for- 

 wards, busily engaged in darting up to cer- 

 tain places about the horso, and at every such 

 movement attaching an egg to a hair, where 

 it usually remains, ready, on the slightest ap- 

 plication of the tongue of the animal, to throw 

 open the lid or valve with which it is pro- 

 vided, and leave the minute bot or grub on 

 the tongue, to find its way to the stomach of 

 the horse with its drink or its food. Lii<e 

 many other insects of a similar class, no 

 sooner has the fly deposited its eggs, than it 

 either falls to the earth and dies, or slowly 

 flies away to perish. 



The time occupied by the egg in coming 

 to maturity, is partly depending on the tem- 

 perature, or its position on the animal ; but it 

 never exceeds a few days ; and at times, the 

 application of a moist warm hand will show 

 they are ready for hatching in twenty-four 

 hours. Wlien, by the action of the tongue, 

 the grub has been removed into the stomach, 

 it attaches itself to the insensible coat of that 

 organ, by the two little hooks with which it 

 will be seen the head is provided. Here it 

 makes a small opening, into which its head 

 or muzzle is plunged, and where it feeds on 

 the juices or mucous which the stomach in 

 that state affords. In this [)osition it remains 

 during the winter, and until the early part of 

 summer, when it detaches itself, and mixing 

 with the contents of the stomnch, is voided 

 with the excrementitious matter. As soon 

 as it reaches the earth, it burrows at once be- 

 neath it, where it remains in the clirysalis 

 state for a number of weeks, and then emerges 

 a perfect fly, busily engaged in the propaga- 

 tion and perpetuation of its species. Such is 

 the history of the common bot ; the one that 

 most frequently falls under the notice of the 

 farmer, and is the most injurious to the ani- 

 mal. 



Besides the above bot, tliere is another, 



called from its colour the red bot. It is 

 smaller than the common bot, and the fly 

 which is its pur-nt Ims never been siitisfac- 

 torily described. It is generally considered 

 more injurious than tlie common one, but 

 probably without sufficient reason. Tlierc is 

 still a third species, the (llslnis hemorrhoi- 

 diiiis, or fundament bot, which makes its ap- 

 pearance within the anus and about the tail, 

 the egg of which, it is ascertained, is deposited 

 by a fly, while the intestine is partially de- 

 veloped in voiding the excrements. These 

 bots occasionally produce a little irritation 

 of the p;irts, but otherwise do not seem to 

 l^roduce injury. They are generally easily 

 detached by the application of a little linseed 

 oil. 



Very discordant opinions are entertained 

 among veterinarians, and among farmers, re- 

 specting the effects which the presence of 

 bots in the stomach of the horse produces on 

 the animal. Some contend that the bot is 

 never injurious ; that it never perforates the 

 stomach of the living animal ; that the deaths 

 attributed to the bot, should be placed to the 

 account of the colic; and that when the 

 stomach is found perforated, as it frequently 

 is, it is done by the insect in seeking to make 

 its escape from the change that ensues after 

 the death of the animal ; and that, conse- 

 quently, all the nostrums that have been pre- 

 scribed for the dislodgment of the bot, are ab- 

 surd if not positively injurious. An able and 

 interesting discussion of this subject, was car- 

 ried on in the 13th and 14th volumes of the 

 American Farmer, between Dr. Harden, Mr. 

 Ellis, and others, during which a mass of 

 facts were adduced, proving that if death was 

 not caused by the perforation of the stomach 

 by the bot, it did cause death by choking up 

 the passages leading to or from the stomach. 

 This agrees with the statements of the best 

 European writers on the diseases of the horse. 

 Thus the Cyclopedia, issued by the Society 

 for the Difltision of Useful Knowledge, says, 

 " In a few instances, the bot has been de- 

 cidedly injurious ; fastening themselves on the 

 edges of the opening into the wind-pipe, they 

 have produced a cough, which no mpdicine 

 could alleviate, and which, increasing with 

 tlie growth of the bot, has ended in an irrita- 

 tion under which the animal has sunk. They 

 have also travelled flirther than the stomach, 

 and have irritated and choked the first intes- 

 tine, and thus destroyed the horse; and even 

 in their natural habitation, under probably 

 some diseased state of the stomach, arisin"' 

 from other causes, they have perforated it 

 and caused death." 



Mr. Youatt, in his work on the Horse, 5jcys 

 the bot " cannot be removed by medicine, be- 

 cause they are not in that part of the stomach 

 to which medicine is usually conveyed ; and 



