_ There are few points in the breeding of stock on which a greater variation of opinion has been confidently expressed than on the origin of the domesticated pig. It has been contended that our various types had a common origin in the wild hog, and that the difference in form, colour, and character amongst the local breeds is due, in the main, to the requirements, imaginary or real, of the interested residents in the particular districts. On the other hand, it is asserted with equal confidence, and probably with the same amount of actual proof, that it would be impossible so to improve the wild hog by selection as to render it the equal of the domesticated hog. There must, therefore, have been an infusion of blood of a cultivated breed of pigs to acquire even that amount of success which was noticeable in the improved pig of a century, or less, ago. Unfortunately, for this argument, it has not been possible to obtain any information of value as to the alleged source of origin of this cultivated breed of pigs.
Again, those pigs which possess in a marked degree early maturity, fine quality of flesh, and those other characteristics of the improved pig, are so various in colour, that one cultivated breed only could not have been utilised in the general improvement.
All the ancient writers on pigs appear to have experienced the same difficulty when endeavouring to discover the sources of origin of the material which might have been used in the production of the pig which in their time was looked upon as the domesticated and improved pig of the period. This difficulty extends even to the present day. So far as is known there exists no actual proof that the domesticated hog has been evolved in any particular way other than by continued selection of those animals for breeding purposes which possessed in the greatest degree those particular qualities held in the highest estimation at the time.
Of course, the soil, climate, etc., of the district in which pigs are reared have a certain amount of influence, but this is noticeable to a much lesser extent with pigs than with horses, cattle, or sheep, since under the present system of pig-breeding the greater portion of the food used in the different districts is of a very similar character--indeed, much of it has a common origin--having been imported from abroad.
As a rule, comparatively speaking very little difference is noticeable in the development, form, and character of pigs bred in the various parts of the country, whereas with some of the other domesticated animals a very considerable change follows the removal of sheep of a pure breed from one district to another. The quality and quantity of the wool, flesh, and bone are all affected. An exactly similar effect is noticeable when horses of a particular breed are moved from one district to another. For instance, a Shire foal bred in the Fens may possess the characteristic bone, flesh, and hair, yet if it be moved into portions of the Eastern counties where the soil is of a totally different character, it will when matured have lost, to a very considerable extent, its peculiar characteristics of bone and hair. The changes wrought may be due in small measure to climate, but the predominant cause must be due to the variation in the food grown on soils of a different character.
This question of the original cause or causes of the varying colour of the pigs in different localities appears to be equally difficult of solution. As to the continuation in certain districts of pigs of one colour, custom and even prejudice have a great effect. So strong is this prejudice that some persons will even declare that the pork of pigs of the fashionable colour in the neighbourhood is superior to that from pigs of any other colour. As this weakness is common in districts where black and where white pigs are kept it must be admitted that prejudice alone must be the foundation of the belief.
Probably the safest conclusion to arrive at with respect to the variation in colour of the pigs noticeable in certain districts is that in the long ago the native pig in the wild state was of the colour of the soil and the herbage in which it sheltered, and was thus less conspicuous to its enemies, whether human or animal. A marked instance of this is to be found in the colour of the common or original pig found in some parts of the country where the soil is of a decidedly red colour. In the district referred to one actually hears some farms spoken of as "red land farms." What more natural than to find in the districts in which land of this hue predominates that the pigs should be a red rusty hue such as was the original colour of that breed of pigs now called the Tamworth breed.
Some persons, who do not agree with this theory of the origin of the various coloured pigs, cite as a proof of their belief the fact that in so many districts the pigs are of a mixed colour, and that this peculiar marking is equally as general in localities as is any particular or special colour in the pigs. This is perfectly true, and it is probably due to exactly the same causes, fancy, prejudice, or custom. The residents in certain districts have grown accustomed to certain things or certain forms, and are loth to change; the manufacturer of any article must humour the actual or fancied requirements of his customers if he is to secure success; and in a similar manner the breeder of pigs has to consider and to produce pigs of the form, size, and colour which are most in demand. Further if, as confidently alleged, there is a preference in some districts for pork from pigs of a certain colour, then the butcher naturally offers a higher price for pigs of that colour which most fully satisfy the fancies of his customers, and thus we find a similarity of form and colour in the pigs of various districts.
As to the origin of these parti-coloured pigs, the explanation offered is that even in pre-railway times there was a certain amount of interchange of the different local breeds of stock. This would be affected in various ways, which need not be specified.
At the present time we have several defined and distinct breeds of pigs which have secured recognition at our principal agricultural shows. Indeed it may be claimed that the exhibitions of live stock which have become so general in all parts of the country have been one of the chief factors in fixing to a certain extent the type and character of certain local breeds. Within the memory of the present writer the classification of pigs at our principal shows was of a very simple character; it consisted of classes for pigs of a white colour and for pigs of any other colour. There was no attempt at any definition as to size, form, and quality of the pigs. These points were left entirely to the judges, who naturally were led to favour pigs of the type which they bred. There was thus a greater amount of uncertainty as to the success of an exhibitor's stock than at the present time. This uncertainty--save as to the members of the Show Committees or their friends--was increased by the unfair system of withholding from the knowledge of the average exhibitor the names of those selected to judge.
The necessity of some definition, if only of colour, quickly became obvious. At first classes were established for pigs of certain colours; then the prizes were offered for pigs of certain breeds, which were more or less loosely defined. Now at the chief shows the pigs exhibited in the various classes must be qualified for entry in the herd books of the particular breeds.
At the Royal Agricultural Shows there have been classes for pigs of the Large White, Middle White, Berkshire, Tamworth, Large Black and Lincolnshire Curly Coated breeds; whilst for the next show classes for pigs of the so-called Gloucestershire Old Spots breed are to be included. As showing the changes which are in progress it may be noted that two breeds of pigs which had classes provided for them at the Royal and some other Shows have become extinct. These were the Small White and the Small Black breeds--the sole cause of their disappearance being the unsuitability of the pigs of the breeds to supply the present requirements of the consumer. _