ERGOT.

New Zealand Journal of Agriculture, Volume 3, Issue 5, 15 November 1911, Page 361

ERGOT.

An Experiment to test the Toxic Properties of Ergot towards Cattle, and, in Particular, the Production of Gangrene of the Feet by its Ingestion (socalled “ Ergotism ”).

C. J. Reakes,

jD.V.Sc., M.R.C.V.S. ; H. A. Reid, F.R.C.V.S., D.V.H.

©N the 29th June, 1911, two young cattle, a steer ' aged eighteen months and a yearling bull, were selected at the Wallaceville

Laboratory for the purpose of carrying out the above experiment. Both animals were carefully examined beforehand, and found to be in normal health and in moderately good condition.

Taylor, in his classic work on “ Poisons,” remarks, in reference to the effect of ergot on the human subject, that “ it does not easily cause death in one large dose, but its fatal operation appears to be more strikingly developed by its long-continued use in small or medicinal doses.” In this experiment it was therefore decided to commence with the medicinal dose, gradually increasing it if considered necessary. For convenience of dosage the liquid extract of ergot, 8.P., was employed. This preparation

represents a solution of ergot in the strength of lin 1. Each animal received daily, in the form of a drench, 4 c.c. (about 1 dram) of the liquid extract mixed with half a pint of water, this dose being doubled on the 7th July, eight days after the commencement of the experiment. On the 18th July the dose for the bull was again increased to 16 c.c. (4 drams), that for the steer remaining at half this quantity. On the 24th July the dose for each animal was fixed at 16 c.c. (4 drams). .

On the Bth August, forty days after commencing the experiment, no symptoms of poisoning nor other ill effect had been induced. The steer had lost condition slightly, but this was probably the result of bad weather and scarcity of grass-feed. The condition of the bull was very good, so that in his case the dose was further increased on the 16th August to 30 c.c., and finally, on the 9th September, to 40 c.c. (10 drams) daily. The maximum daily dose for the steer remained at 16 c.c. (4 drams). These quantities of the Liquid Extract of Ergot were given every day (with the exception of three days from the Bth August, when the experiment was unavoidably held over pending the arrival of a fresh supply of ergot, which had failed to come to hand when ordered) until the 26th September, covering a period of eighty-nine days for the entire experiment. No toxic symptoms having been set up throughout that time, it was decided to discontinue the dosage.

The steer, which, it will be remembered, was receiving the smaller dose, at one time suffered from diarrhoea, lost condition, and showed slight swelling of the hocks, but these symptoms were attributed to the presence of internal parasites (Strongylus ostertagi and 8. cervicornis), and gradually disappeared on the nutrition of the animal being improved by means of additional dry feed.

Altogether the bull calf received 65 oz., or 3J pints, of Liquid -Extract of Ergot, extending over a period of nearly three months, the steer receiving for the same length of time 2 pints. The climatic conditions prevailing at the time were not favourable to the resistant powers of the animals, the weather for the most part being cold and often very wet. At no period of the experiment was any lameness apparent, nor were any signs of disease of the extremities shown.

In order to ascertain whether the ergot produced any topical effect when brought into contact with an abraded surface, a quantity of the Liquid Extract was applied to a scarified area between the claws of a yearling heifer. This treatment was repeated for twelve days without producing any ill effect, the scarified portion at the end of that time having healed. '

Remarks.

In his work on “ Veterinary Medicine,” Finlay Dun states the dose of Liquid Extract of Ergot for cattle to be Ito 2 drams. The drug is pre-

scribed medicinally in order to check haemorrhage after calving, to promote contraction of the’ womb, and to hasten the expulsion of the afterbirth. The same authority writes that ergot given experimentally, in large or continued doses, causes ergotism, a condition characterized by derangement of the stomach and bowels, nausea, arid diarrhoea. ' Its effect upon the circulation causes dry gangrene, chiefly involving the extremities, ears, and tail, and may also produce inco-ordinate spasms, and sometimes epileptiform convulsions. Under “ Toxic Effects,” Dun mentions that these are not so marked in horses, cattle, sheep, and rabbits, as in men and dogs.

The following experiment is quoted in illustration of the above : “ Thirty cows amongst them took daily with impunity 37 lb. for three months ; two milk-cows had between them 9 lb. daily, with no further evil effect than that the butter was badly tasted. Twenty sheep amongst them ate daily for four weeks 9 lb. without injury. Dogs, on the contrary, suffered violent illness after receiving 6-12 drams, while 3 oz. proved fatal to a terrier bitch in twenty hours. Chronic poisoning occurs, especially in patients placed in unfavourable sanitary surroundings. . / .

Gangrene of the extremities is not, however, produced so readily as in man.”

Gilruth in 1905 carried out feeding-experiments on cattle and sheep, using a commercial sample of the dried ergot sclerotia for this purpose. The ergot was fed to the experimental animals mixed with damp chaff. In forty-five days a calf consumed 10| lb. of ergot, and in the same period a sheep ate 1| lb., while another sheep took fib. of the ergot-spurs. No ill effects followed.

Although insufficient in extent to be conclusive, the result of this present experiment goes to indicate that the effects of ingestion of ergot by cattle are not as appreciable as popularly supposed. It serves also in the same measure to support the conclusions arrived at concerning the cause of gangrene of the feet, a condition shown to be associated with the presence of a specific organism. (See Annual Report, Department of Agriculture, 1910.)

In connection with these experiments it is worthy of note that the unstable character of the active constituents of commercial ergot is generally recognized, many preparations and samples of the drug being found quite inactive. In view of this it is evident that further work is necessary, and it is proposed to carry out more feeding-experiments with freshly collected ergot if sufficient be obtainable, with the object of testing the matter under more natural conditions.- The results will be published in due course.

At the close of July foot-and-mouth disease existed on no less than .31,926 farms in Germany. ■ “