A few weeks before the Field induced Dr. Klein to take up the question of grouse disease and to go to Scotland to investigate, the author had prevailed upon M. Pasteur to offer to examine the disease, and it was after this was announced in the Times and Morning Post that Dr. Klein began his work. The author regretted that he did undertake it, because it just prevented the necessary grouse being sent to M. Pasteur, and that great man had a way not only of discovering bacilli but also of some way of killing them. Dr. Klein may or may not have discovered the bacillus of the grouse disease, but if so he never gave the disease to a healthy grouse, nor did he even attempt to discover a cure for or prevention from the disease, and however interesting to science his discovery may have been, it was of no use in practice. If he did really discover the cause of the disease, and if grouse are only subject to take the disease in the same manner as the creatures to which he administered his disease, then there appears no escape from the conclusion that the disease is injected under the skin of healthy grouse.

Every one knows that grouse disease generally shows signs of its coming, and yet when it really attacks a bird the latter often dies within a few hours. The author consequently does not believe that the bare legs and dull plumage associated with grouse disease always imply that the birds have the disease, but only that they are in a condition in which they can more easily take it, or have had and recovered from it. This view is supported by the fact that, after the last attack of grouse disease in Badenoch, it was noticed when the birds re-started to breed that the young ones were well feathered on the legs and the old birds were not. What had happened to those old grouse? Had they had the disease and recovered from it, or had they only had that predisposing indisposition that causes the leg feathers to fall off and the other feathers to look dull? If they had had the disease, then it is not as fatal as Dr. Klein’s experiments suggest. The chances are that tapeworm or any other parasites, or even prolonged wet summers or bad food, will predispose the grouse to the reception of bacilli, possibly by midge bites on bare legs conveying disease from the sick to the healthy. This view is supported by the fact that the grouse never get the disease, however bad their food and however bare their legs in the hard winter weather, but only when it is warm and damp and there are lots of midge flies.

It has often been said that all game birds and domestic poultry are subject to the same diseases, and it is frequently suggested that the grouse disease, pheasant disease, and fowl diseases are all one and the same. That is an extraordinary belief, because pheasant disease nearly always occurs when the foster-parents from the barn door remain perfectly healthy. These views have had a still further upset in the summer of 1906, by the fact that a large number of foster-mothers died of enteritis, but without any of the pheasants becoming sick. It is quite clear that the pheasant disease of the rearing-fields is as much a mystery as it was before pathological research began, and is one of those things that is waiting for investigation. How it is spread is not even known. Post-mortem examinations without bacteriological research are freely made, and opinions as freely offered, generally ending in a recommendation to keep fewer birds. This advice is very wisely not followed by those who want more, not less, sport. And the preservers have this in their favour, that pheasants increase in numbers every year in spite of disease. Game preservers are in these times well aware that opinions given on a mere inspection of the internal organs can neither lead to true knowledge of the cause of deaths nor even to wise suggestions of how infection may be avoided. It is not known whether the chicks catch the disease from the breath of already diseased birds, from foul feeding on excretatainted ground, or from inoculation by means of fleas or other vermin. Although these points could be set at rest in a week when disease breaks out, it never has been done. It seems more likely that, as in cramps, the disease bacillus is present in soils suitable for it, and not in others, or else that some soils favour the development of the diseases in the birds. The only way known to avoid either of these diseases is to avoid the ground on which they occur, but numbers of birds do not create either disease. The perfect health usually found on the game farms proves this. There they generally have as many pheasants on 100 acres as sportsmen expect on 10,000 acres. As with grouse, the greater the stocks the more healthy the birds seem to be.

Partridges are most attacked by a disease known as “the gapes.” Hand-reared birds can be dealt with more or less successfully by means of fumigation. Carbolic acid crystals are volatilised on a hot shovel within a closed coop containing the affected birds. However, this is a clumsy way of dealing with the matter, and the best plan is to move the birds that show signs of being troubled with the disorder to the woods, where they can get lots of insect food as it falls from the trees. This applies to both partridges and pheasants. In the wild state the former are most subjected to “gapes” when the weather is very hot and dry. It is not known how the worm that is the cause of the trouble gets into the air passages.

There is a large number of other diseases to which game birds are subject, but a preserver who can avoid those mentioned need not trouble about the others. That is the reason they are not mentioned in this work on Shooting.

But an additional word may perhaps be said on grouse disease. A Departmental Committee of Investigation has been formed by the late President of the Board of Agriculture to investigate the disease. One of its first acts was to issue a pamphlet to correspondents to show what had already been said and thought about the disease. None of these old faiths are in agreement with Dr. Klein’s conclusions as they stand, but it only needs one factor to be assumed to bring them into agreement, as will be seen by the following table:—

It may be remarked that it is no answer to say that tapeworm cannot be a cause of predisposition to disease, because it is always present. It is greatly more in evidence some years than in others. The author never in any other year than 1873 saw quantities of shot grouse from which tapeworms exuded in yards of entangled mass from the shot wounds of the dead birds. Then, however, they did so, and had to be withdrawn from the birds before the latter could be bagged. The birds could not have been left upon the moor, because the dogs would have gone back for them. Yet with all these worms the only evidence of disease was an absence of much leg feathering. The owner of Glenbuchat has been good enough to tell the author that disease broke out there in 1872 after the shooting season, but he never before heard of any disease in that year, and as a matter of fact the grouse at Aldourie, in Inverness-shire, not far away, bred well in 1873, and only were attacked by the disease later than the shooting season of that year. But even 1874, the great disease year, was by no means universally bad. That autumn they had a splendid crop of grouse in perfect health at Crossmount, in Perthshire. The Rannoch Lodge ground was only fair that year, but the author’s party there was credited in the Scotch papers with the record bag for that season, probably wrongly, as there was not one bird for five compared with the little moor of Crossmount. 1873 was very wet in the August and September shooting season, and the writer never before or since saw so many midges as in that season. That grouse disease does not attack in winter (although many grouse die then and in the spring of various complaints) also tends to prove that the bacilli must have an intermediate host that is not in evidence in the cold weather. Then the disease is not known in Ireland and in the Lews, where the climate is mild and damp and encouraging to midge flies. But there is really no place that the midge can attack a grouse as long as he is full feathered, and in the mild climate even if there were starvation there would not be bad food. But it may very well be that the bacilli do not exist in Ireland or the Lews, and until it is proved that they do exist there it is beside the mark to set aside the evidence to be had where they do exist, only because it does not conform to that of a place where they are unknown.

For some reason that the author is not aware of, the Field, which commissioned Dr. Klein’s investigations, seems to have thrown over his conclusions entirely. Without any remark upon the wisdom or otherwise of this course, it is necessary to show how thoroughly it disagrees with them. At random the author takes the issue of October 6th, 1906, and he finds therein these four references to grouse disease. At page 581 is stated that “pneumo-enteritis is the technical name of the grouse disease.” On page 591, Mr. W. B. Tegetmeier writes: “During the present year the number of grouse that I have seen affected by disease has been unusually small, not half a dozen from all parts of the kingdom. The extension of the disease to blackcock is an interesting fact that should be known. The disease appears to confine itself almost exclusively to gallinaceous birds.”

On the same page the Field says: “Partridges were practically exempt from pneumo-enteritis as long as they were allowed to breed naturally, but overcrowded on foul ground they will become as subject to it as pheasants.” And on page 592, in reference to pheasants it is said, “The birds died from very severe pneumo-enteritis.” On September 22nd, page 531, Mr. Tegetmeier has an article in which he seeks every means of discovering why foster-mothers have died of the disease and the pheasants have not died. Consequently, it is evident that the journal treats this disease as one and the same in all species of gallinaceous birds. But Dr. Klein said at page 38 of his book on grouse disease, “In pigeons and fowls the subcutaneous inoculation is not followed by any, not even a local, positive result; the animals remained lively and well.” In fact, Dr. Klein failed to give the disease he had discovered to fowls or any gallinaceous birds whatever, but he said, “The most striking results were obtained on the common bunting and the yellow-hammer, for the injection of a small drop of the broth culture into the leg is followed by fatal results.”

Obviously, if the Field is right now, Dr. Klein did not discover the grouse disease bacillus. And if he did discover it, any fowls dead from or sick with disease may at once be regarded as victims of something else; and other gallinaceous birds must be suspected in consequence of being refractory to the grouse disease.

The author’s belief is that Dr. Klein did discover the bacillus, although he failed to prove it, and that his experiments on buntings, fowls, and other creatures went to suggest that the grouse is not a natural host of the bacilli, that it or its virus becomes attenuated or weakened every time it passes through a grouse, but that, on the contrary, it becomes more virulent in passing through buntings and yellow-hammers. This was suggested by the weakness of the virulence from the bacilli cultivated from the diseased autumnal grouse after a severer spring outbreak, and it is also suggested by the fact that in such cases the grouse do not die rapidly, and that it is a slow disease from which perhaps some grouse recover; whereas they do not recover in the spring. The writer’s suggestion is, therefore, that when the bacillus is carried from grouse to grouse it may be weakened, but that in spring it is not originated in the grouse, but in some creature unknown, and possibly a migrant bird of the bunting, hammer, or finch families. The importance of finding this out, and testing the attenuation theory more thoroughly in live grouse, is obvious, for if it is true that the blood of successive grouse gradually weakens the bacilli or their virus, then it is clear that the safety of grouse will be the constant presence of some few diseased grouse on the moor.

The author only dwells on this aspect because it is not receiving as much attention as some others, which are constantly being discussed, and are therefore less necessary to mention.

At present thought is mostly in the contrary direction. But it is to be hoped and believed that the Commissioners will investigate every possible view from a scientific standpoint, and more important still, from a practical one. For instance, if on a disease affected moor grouse can be kept in health in a pen of midge-proof netting, we shall hardly need to know where the midge gets his poison, but shall be exceedingly likely to dry up his breeding-places and exterminate him as nearly as may be.