Imágenes de páginas

substitute for the misnomer “hog cholera,” but since the gastric lesions are the least common, and not, by any means, always present, probably the best name is that adopted by Dr. Klein, i. e., "contagious pneumo-enteritis."

This disease does not depend upon the particular kind or quantity of food consumed, upon the character or nature of the soil, nor any peculiarities of breeding; but, like yellow fever and cerebro-spinal meningitis in man, must be attributed to the presence of a specific poison in the atmosphere. Certain foods may operate, from the extreme sensibility of the bowels, to render the attacks more violent and fatal, but these consequences should never be confounded with this special virus, which is, per se, in every instance, the cause of “hog cholera.” It does not appear necessary for me to go through a long and precise description of the history, symptoms, &c., &c., of this disease, as the reports of the Department of Agriculture contain this in extenso.

The first thing to be appreciated by those who suffer by this malady is the fact that this is an infectious disease, due to a specific poison, which is transmitted from place to place, and from herd to herd, through the media of the atmosphere; by the clothes and implements employed by man; in the hair of dogs that have eaten carcasses which were affected with cholera ; in the plumage of birds, (buzzards and ravens principally,) and freuqently by streams of matter into which infected hogs have droped their fæces.

Allowing the sick to herd with the well, of course, is a fertile source of the contagion. It is estimated that the germs of this poison can be transmitted from the emanations arising from an unburied carcass through the atmosphere, and cause contagion at from one half to one mile. Appreciating then the character of the disease, and its mode of propogation, what are the indications for treatment, both preventive and curative? The answer is so pertinent that it seems like a waste of words to hint, even that legislation is necessary t oinduce men to conform to these indications. Yet such is the case. As the disease is now treated, the sick are, in most instances, allowed to run with the healthy; they eat from the same trough ; they occupy the same litter; they breathe the same air. The emanations from the fæces of the sick (probably the most fertile source of the contagion) are breathed in daily by the well; the carcasses of those which have succumbed to this affection are dragged out and left lie on top of ground, and often on high points of land where the wind has every possible chance to disseminate these poisonous germs. As a rule, no disinfectants are employed. So long as this treatment is pursued, hog cholera will exist and spread.

As soon as one death has chronicled the existence of this disease in a herd, there should be a vigilant watch kept on all the rest. The


should be, at once, thoroughly cleaned by white-washing the sides and scrubbing the floors, and applying crude carbolic acid or chloride of lime on the trough, floor, and on the manure pit. A bottle of carbolic acid, with the cork removed, should be hung up in the pen. If any new cases develop, remove, immediately, to as great a distance as possible, from the well, and place the siek in charge of a person who is not to have, on any consideration, access to the healthy. Bury or burn all dead bodies without delay. Be profuse in the application of disinfectants in and about the pens of the sick.

A vast number of preventive "remedies” have been heralded, but I believe them generally to posssess little or no virtues. The best, probably, of all these is charcoal. It posseses the virtues of a disinfectant to a high degree, and is readily eaten by hogs. Sulphur, antimony, copperas, &c., &c., have been used, and, although tonics, like sulp: iron, may fortify the system to a certain extent against the disease, they can have little to do with eradicating the poison.

Insolation, disinfection, and a proper and immediate disposal of all dead bodies are the sine-quanons toward breaking up and exterminating this disease. If these measures will not be followed without legislation, then pass laws, and appoint competent men to enforce them, and reasonably hope for a deliverance from this evil.

So far ascurative treatment is concerned it seems to me to be impracticable to carry it out; un'ess we had a specific. All that need to be done is, I think, to isolate the sick in well-ventilated, well-littered, and thoroughly disinfected stables; if the bowels are costive, to give an oleaginous purgative; if a diarrhoea is persistent, to give an astringrnt; to keep before them a charred log; to give them lime water with their milk, and to meet special developments as they arise. A course of vegetable and mineral tonics will be found advantageous during convalescence.

Health is so slow in being resumed, in most cases, that it is a question to decide whether there is not more economy in killing the sick, as soon as the symptoms are well marked, than in treating them through a convalescence which sometimes extends to months.

The government must appreciate the necessity of these preventive means, and grant sufficient appropriations to effectually carry them out, before much good can result, and these enzootics and epizootics be held in check.

CHARLES B. MICHENER, D. V. S., Veterinary Surgeon of Pennsylvania State Board of Agriculture.


By Prof. J. STAUFFER, Lancaster, Pa.

[NOTE BY THE SECRETARY.—Numerous inquires having been received from correspondents, relative to the habits of various insects deemed injurious to the cabbage plant, and sundry specimens (some of which were the friends of the truck growers and the enemies of the real causes of damage) having been sent to this office, I referred the whole question to Mr. Stauffer, who replies as follows:] Secretary Pennsylvania Board of Agriculture :

DEAR SIR: Mr. Harris described the pot-herb Pontia as the “ Pontia Oleracea " in the seventh volume of the New England Farmer, in 1829, nearly fifty years ago; and what he then said has been very little improved upon in point of fact. I might copy verbatim what is published at page 270 in Flint's edition of 1862. For what is said of the “ Pontia Oleracea" applies to the multitorm group of species known as the " Pieris," adopting Schrank's generic name instead of that of “ Pontia,” under which generic name, Vincent Köllar, described three species in his excellent Treatise on Insects injurious to Gardens, &c., translated by J. and M. Loudon, with notes by J. O. Westwood, F. L. S., London, 1840. Our Pieris rapae is considered identical with the European species said to have been intro

[graphic][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][ocr errors][ocr errors][subsumed][ocr errors][subsumed][subsumed][subsumed][subsumed][ocr errors][subsumed][subsumed]

Fig. 1. Pieris Rapae, female, depositing eggs on a cabbage leaf,
Fig.2. Natural Size of wings showing the upper surface
Fig.3.a. A catterpillar having formed

the band and hung itself in the loop:
6. À chrysalis, c. Aparasitic fly. Fig$ 4.5 & 6. Larva. Fig. 7. Eggs & hatching magnified.
Fig. 8. Male P. Rapae. Fig. 9. Oleracea Fig. 10.P Protodice


[ocr errors]

duced from England to Canada, in 1856 or 1857. It was first taken in Quebec, in 1859; in 1864, it had spread about forty miles from Quebec as a center; in 1866, it was taken in the northern parts of New Hampshire and Vermont; in 1868, it had advanced still further south, and taken around Boston and a few in New Jersey. Fig. 9 represents P. Oleracea of Harris. Fig. 8 the male, and 1 and 2 the female, P. Rapæ, and Fig. 10 the P. Protodice, or so called southern form, with their larvæ or catterpillars, Figs. 4, 5, and 6, on the cabbage leaf. My attention was first called more particularly to this subject from specimens sent by the editor of “Moore's Rural New Yorker," August, 1870, of the P. Rapae. I may be excused from giving a full description of the difference in the spots and colors of the various species mentioned, when I state, that according to the lenghtly report by H. S. Scudder, (in Proc. Boston Soc. Nat. Hist., viii, 1861, 178,) setting forth the interchange of names of species described by Harris, Boisduval, and Kirby of the P. Oleracea, and P. Rapae of Europe, and the P. Protodice which he says is the American representative of the European daplidice, the Alpine Callidice, the Siberian lencodice, the South American autodice, the Arabian glanconome, and the South African hellica.

The illustrations will answer as well as lengthly descriptions. Scudder also says: “No possible step in the gradation from one extreme to the other is wanting, and both extremes are found equally among numerous examples from as widely distant places as Massachusetts and the Great Slave Lake, though the suite of specimens compared, indicate that thie paler forms are more commonly met with in the southern localities, and the more heavily marked ones are the characteristic forms of the north,” this is at variance with P. Oleracea and P. protodice. The character and habits of all are substantially the same. The variation in color or spots of the perfect insect or catterpillar. Notwithstanding, we may consider them as a group of pests to the cabbage garden, but we may state here that there are other insects that infest the cabbage, and in order to write intelligently I design to confine each group to its own order or sub-division.

The Pieris belong to the diurnal or day-flying butterflies. Order-LEPIDOPTERA, (scale winged, hence the German name Staubflügler, also called Schmetterling.) The states through which insects pass may be adverted to the egg, the larva, the pupa, and the imago or perfect insect. There are common names that should be properly used; the larvæ, whether smooth or hairy of butterflies and moths, we call caterpillars; those of beetles, grubs ; of flies, maggots. The word worms applies to the earthworm and should be confined to true vermes. As the pupæ of butterflies are often tinged of a golden color or jeweled, the Greeks called them chrysalides, and the Romans aureliæ. We term them chryalids.

The female Pieris deposits her eggs in twos or threes, sometimes in greater number, scattered along the ribs of the cabbage leaves on the underside. They may be seen hovering over the cabbage bed or other cruciferous plants in the latter part of May and the beginning of June, this is a good time to catch them with a bag-net of muslin or thin netting over a hoop, on a pole; they fly low and rather sluggish. To capture and destroy them before their eggs are deposited, is to nip the evil in the bud, and as the old adage has it, “ an ounce of prevention is better than a pound of cure.” These eggs are about the one fifteenth of an inch in length—pear shaped—of yellowish color, and have a series of longitudinal ribs. Figs. 7, d, e, and ), show the egg enlarged, the position of the young larva, and the manner of its escape from the egg. They are hatched in a week or ten days, the young larvæ immediately take their station along the veins of

« AnteriorContinuar »