TREMBLING IN SHEEP. LOUPING-ILL. INFECTIVE 

 MYELO- MENINGITIS. IXODIC TOXAEMIA. 



Definition : infective, tick-borne disease, characterized by meningo-mye- 

 litis. Animals susceptible : sheep, and possibly swine (Meek, Greig-Smith) 

 and cattle (Williams). Known in North Britain only in spring (in Sky e 

 also in autumn), on rough pasture with much brush, and wood ticks, 

 (Ixodes ricinus, erinaceous, marginatus or other). Experimental infection. 

 Bacteriology : Bacterium fluorescens /3 and 7 found in exudate and infect- 

 ing. Accessory causes : dried grass of previous year, brush, low condition, 

 cold, youth. Symptoms : incubation 10 to 30 days ; impaired innervation, 

 hypersesthesia, timidity, excitability, trembling, jerking, lack of coordina- 

 tion and balance, falling, convulsive struggling, jumping, rolling of eyes, 

 stiffness, opisthotonos, paresis, paralysis of hind — later of fore limbs, apathy. 

 Wry neck, arched back, stiff joints. Diagnosis from myelo-meningitis by 

 its enzootic appearance, in spring, on tick infested ground : irova paralytic 

 rabies^ also by absence of that disease locally ; from tetanus by its general 

 prevalence, the absence of tonic spasm, and presence of palsy ; from braxy 

 by the lack of emphysematous swellings, and of speedy sepsis ; from an- 

 thrax by usually healthy spleen and its confinement to sheep. Lesions : 

 cerebral meningitis with encrease of subarachnoid fluid, of myelon, red- 

 dened, .'oftened, also of other serosa, stomach, bowels, liver and kidneys. 

 Prevention : destroy ticks in winter by burning grass and brush, by plough- 

 ing and cropping ; or fence off y^, the pasture one year and the other half 

 next ; or lime soil ; or dip repeatedly in April, May and June to keep off 

 ticks ; avoid moving sheep iu these months : Give liberal feeding. Mor- 

 tality 10 to 20 per cent. 



Definition. Aii infective disease of sheep, iuocalated by ticks, 

 and producing a meningo-myelitis, with drowsiness, hyper- 

 se.sthesia, irritability, paresis and other nervous disorders. 



Animals susceptible. This is almcst exclusively a disease of 

 sheep, yet Meek and Greig-Smith claim to have seen it iu swine 

 that have eaten the raw carcasses of louping-ill sheep, or that 

 have ranged the tick infe.sted pastures, and in rabbits inoculated 

 with the microbe from the wound caused by the tick. W. Wil- 

 liams claims to have seen well marked cases in cattle, and heard 

 of cases in horses and swine. He speaks, however, rather ob- 

 scurely of ''the tick disease" and seemingly includes in this all 

 affections inoculated by ticks. 



Geographical Distribution. This di.sease has been hitherto de- 

 .scribed as existing in the northern part of Great Britain only, 



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