500 Cyst-affected Beef and Pork. [part iii. 



the most important practical observation that, when a calf is infected, and slaughtered 

 some nine or ten months subsequently, the cysts will be found to have become 

 degenerated in all parts of the body ; gritty calcareous spots {^perfectly harmless) alone 

 remaining to mark the situation formerly occupied by the living parasite. Such 

 being the case, the probability of the flesh of cattle being infected with cysticerci 

 diminishes in proportion as the animal is over two years of age. It is believed that 

 a somewhat similar rule may be applied to pigs, although no definite experiments 

 have, as far as I have been able to ascertain, been recorded. In Calcutta it is the 

 young growing pig which is liable to be infected in this manner, and many of the 

 Chinese butchers are aware of this fact, so that the slaughtering of a pig suspected 

 of harbouring measles is delayed for some months, even though the animal be fat and 

 in every other way eligible for the market. 



The diagnosis of this condition in pigs and cattle before death is by no means 

 easy, unless the number of parasites be very great ; although in some of the seaports 

 of Northern Europe, trained men have been appointed, who have acquired considerable 

 precision in detecting the disease in pigs intended for exportation. The general 

 condition of the animal may be bad or excellent ; symptoms of local irritation may 

 exist or they may not, so that no precise method of diagnosis can be given. If, 

 however, the cysts be extensively distributed throughout the tissues of the animal, 

 their existence may very generally be detected by passing the finger along the eyelids 

 or inserting it into the mouth, and feeling more especially the mucous membrane at 

 the root of the tongue, beneath which the little cysts may often be felt as nodules 

 about the size of peas. If felt, the slaughtering of the animals should be deferred 

 for six or twelve months, or until these nodules disappear. The method of detecting 

 the presence of trichince* in the flesh of the pig and in human flesh infected thereby, 

 namely, cutting out a fragment of muscle with a sort of harpoon, is not applicable 

 to the detection of cysticerci, for in probably nine cases out of ten the piece of 

 muscle thus scooped out would contain no trace of the parasite. 



The only reliable preventive measure at our disposal is proper cooking of all 

 meat ; by this I mean exposing every particle of the meat to an amount of heat 

 sufficient to destroy the vitality of each cysticercus. 



With the view of ascertaining definitely what exact amount of heat is required 

 to do this I have made numerous experiments with cyst-infected meat in all stages 

 of growth, a brief resume of which is here given. When a living cysticercus is 

 removed from its host and placed on the stage of the microscope and watched for 

 some time its muscular tissue is seen to contract and expand, and it is even able to 

 shift its position on the slide. Frequently, however, no such indications of life are 



* It is by no means uncommon to find that the prevalence of measled meat in a locality has been attributed 

 to the existence of the trichina gpiralis, which gives rise to what is called the tricMniasis or the " flesh-worm 

 disease " so prevalent in Germany a few years ago, and undue alarm has arisen from the misconception. This 

 worm belongs to a totally difEerent order, its mode of growth and multiplication is different, and the result 

 of infection on the human body vastly more serious. 



