Finally, with no small proportion of them combinations of the different foods are mere questions of convenience, they holding to the notion that the all-important essential is quantity, and, food being food always, quality is a trivial matter. These are some of the most noticeable faults which appear in the practices of breeders of to-day, and in the face of them it is not surprising that failures are so frequent and such a large proportion of dogs are so often out of condition if not the victims of disease.

The first point of essential interest and importance to be considered is the proportion which the several ingredients of the mixed diet should bear to one another. Unfortunately no rule which will admit of wide application can be fixed here, for the requirements are influenced by the age, amount of exercise, condition of health, seasons of the year, individual peculiarities, etc. A puppy, young and growing, needs in proportion a more generous quantity of animal food - milk or meat for muscle and bone building than he will after he has matured and his structure is complete. During the hunting season and while his muscles are being constantly drained as it were by his work a dog can not only assimilate more meat, but actually requires a much larger proportion, than he that is kept much of the time on the chain and allowed but little exercise. This important fact can perhaps be given greater prominence by the assurance that an excessive indulgence in meat has much the same effect upon dogs as upon members of the human family; and surely no one will gainsay that while men who work hard, as with the pick and shovel, can eat freely of meat twice and three times daily and be none the worse for it, were students, book-keepers, or others of sedentary occupations, to attempt such a diet, in a short time they must become dyspeptic, bilious, and otherwise disordered.

In estimating the daily quantity of meat some modification is allowable and often demanded according to the physical condition. Considering the fact that this food tends to produce firmness of muscle with an absence of superfluous fat, while vegetable food on the other hand tends to increase the deposition of fat, manifestly in many instances of underweight it is advisable to give less meat and more vegetable food. In some instances, also, the requirements are the reverse of these, and, as always with bitches that are too fat, it is necessary to feed largely if not entirely on meat until good form is restored.

This, by the way, bears specially on bitches that are not in-pup. And yet such treatment would be safe for those that were, provided with them the increase in the amount of meat was made gradually and there was a corresponding gradual increase in the amount of exercise. But lest the reader draw wrong conclusions here it is urged that assuming the bitch to be one that had been accustomed to a diet consisting of about one-third meat, to put her on to all meat while she was in whelp would be hazardous were she afterward given the same amount of exercise which she had been having and no more. Furthermore, during gestation a bitch could not safely bear the amount of work that a dog fed entirely on meat must have had she been given but an average amount of exercise up to that period.

In estimating the daily quantity of meat an allowance must be made for the season of the year, since the digestive and all other functions of the body vary under the influence of cold and heat - the former stimulating them and the latter depressing them. And manifestly were these variations ignored and the same quantity of meat given daily all the year around, diarrhoea and other disturbances of the digestive organs would be likely to occur in hot weather; moreover, the tendency to skin diseases attended with intolerable itching would then be decidedly greater, in consequence of the system being clogged with impurities, which are inevitable where the excretory organs are unnecessarily taxed, as they always are when too much animal food has been taken into the stomach.

Possessing as they do the power of accommodating themselves to changes in diet, quite pronounced individual peculiarities in relation to tolerance of certain foods must often be encountered in dogs, and these must be considered in estimating the quantity of meat required.

For instance, toy terriers cannot bear much meat because they are peculiarly susceptible to its stimulating effect and are quickly and seriously disturbed by an excess; the results of which are an impairment of the integrity of the blood, a feverish condition of the system, skin eruptions and falling off in coat.

Again, there are physiological drains upon the constitution, such as that felt by the nursing mother or by the dog much used in the stud, and unusual demands upon it, as in sickness, which have to be provided for by an increase of the daily quantity of meat.

It must be remembered, also, that in many morbid conditions this food must be almost wholly relied upon, not alone because there is a decided repugnance for nearly all other foods but because this is the only one that languid digestion can readily dispose of.

Meat produces a greater feeling of satiety than any other food and forms a greater stay to the stomach because that organ is the seat of digestion and is occupied by it for a longer time. And this fact has a bearing on the question of quantity, for obviously a dog fed once a day only can dispose of and more than likely requires a greater quantity of meat daily than another given two or three meals each day.

It is plainly evident from this that dogs cannot be fed by rule, and that the proportions of ingredients of their diet must be intelligently estimated and varied according to existing circumstances.

Before going further it will be well to compare briefly the relations and effects of animal and vegetable foods. The former are identical in composition with the structures to be built up and kept in repair. On the other hand, although no such identity appears in vegetable foods, yet to a marked extent they agree in composition with animal foods, and all that is necessary for the human body at least can be supplied by the vegetable kingdom solely. But the process required for the digestion of vegetable foods is more complex than that required for animal foods, and while the digestive apparatus of man, built upon a more extended scale, can properly dispose of both kinds of foods with nearly if not quite equal ease, owing to its much simpler construction that of the dog is better adapted to animal than to vegetable foods; and although it can successfully deal with the latter its capabilities in this direction are narrower than those of the digestive apparatus of man.