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Pig: Breeding, Rearing, and Marketing, The
Chapter 3. Cross-Bred Pigs
Sanders Spencer
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       _ CHAPTER III. CROSS-BRED PIGS
       This term has a varying meaning to different persons. There are those who term a pig a cross-bred unless it be bred from parents of recorded pedigree, or those which possess pedigrees capable of registration. Others claim that a cross-bred is any pig which is bred indiscriminately from boar and sow of no particular type or breeding--in fact common pigs of the country; whilst still others declare that the title of cross-bred can be legitimately applied only to a pig whose parents were of two different pure breeds in contradistinction to a pig sired by a pure bred boar, and from a common sow, or the diverse way.
       It is not for us to determine the knotty point, but we may venture the opinion that the two first definitions of a cross-bred are not convincing to us, since in order to produce a cross-bred it is necessary to have a sire, or a dam, or both of defined breeds. Probably the most correct definition of a cross-bred animal is one bred from the mating of sire and dam of two distinct breeds, but the term is now loosely applied to an animal begotten by a sire or from a dam of pedigree breeding, the other parent being of no particular breed.
       This system of breeding has become somewhat common owing to the comparatively small outlay required in the purchase of a boar as compared with the purchase of both boar and sows, and also to the belief which is general that a greater improvement in the produce is noticeable when the boar is pure bred and the sows of ordinary or no particular breed, than if the sows are pure bred and the boar a common bred one. In addition to this there is the important point that the pure bred boar should be able to beget at least fifty litters in a year whereas the pure bred sow will not produce more than two litters annually, so that the advantage obtainable from the outlay on one pure bred boar is twenty-five times as great as is possible from the purchase of a pure bred sow.
       There is also another advantage to the owner of a boar who has only a limited number of sows, he can allow his neighbours to make use of his boar on payment of a liberal service fee, which combined will partially pay for the prime cost of the boar.
       A considerable number of pig breeders are influenced in the purchase of a pure bred boar rather than of a sow by the belief that pure bred sows are neither so prolific nor such good mothers as are common bred sows. This belief was even more common in years gone by than it is at the present time, and it must be candidly confessed that there existed substantial grounds for it. Some fifty years since it became fashionable, particularly amongst those who had suddenly become rich by trade or in other ways, to exhibit live-stock at the agricultural shows. They may have been animated by the laudable desire of endeavouring to assist farmers and stock breeders generally, or a desire to gain a place in the sun may have had some slight influence. As the majority of these exhibitors of stock had no special knowledge of stock, they were compelled to place themselves entirely in the hands of their managers and stockman, who generally received by arrangement a certain percentage of the prize money won by the stock. It was then only natural that they gave far more attention to the show points of the animals in their charge than to the breeding qualities.
       The supply of pedigree animals was also very limited at about the period mentioned so that it was much more difficult to avoid too close breeding, nor was there the same care taken in the private record of the pedigrees of the animals bred. These various causes combined led to a loss of vitality amongst the so-called pedigree stock, and this weakening of the constitution showed itself in a reduction in the number of the offspring and in the power of the dam to furnish its young with a full supply of well-balanced milk.
       There is little doubt that in the third quarter of the past century a considerable proportion of the pedigree sows were not so prolific as they ought to have been, nor did they produce and rear thoroughly well so many pigs at each litter as the common sow of the country was capable of doing. A more general study of stock breeding has tended to compel attention to the practical apart from the show points of pedigree pigs, but probably the strongest influence has been the formation of the various breed societies, and the registration of the produce including the number, sex, and sire of the pigs. These entries most clearly showed those breeders of pigs who had paid most attention to the utility points of their pigs, especially those particular points in which pedigree pigs were generally believed to be deficient. The succeeding records of sows of the same families afforded the best possible confirmation of the belief which was becoming general that prolificacy like many other qualities was most certainly hereditary. This recorded proof that pure bred animals and especially pigs were not necessarily slow breeders, helped vastly to increase the demand for pedigree animals for crossing purposes in the breeding of commercial stock.
       The enormous benefit which has resulted from the use of pedigree sires is most clearly proved in the Irish live stock. The so-called premium bulls and boars are pedigree animals purchased by or with the sanction of the Live Stock Commissioners and placed at the service of the general public at a somewhat reduced fee, the Government paying to the owner an annual premium of some [L]15 for each bull, and a certain sum for each boar.
       It is alleged that the original improvement in the ordinary pig stock of those parts of Ireland where pig-keeping on a considerable scale is followed, was due to the purchase in England of numbers of Large White boars, as after experiments carried out in Denmark, these boars were found to effect the greatest improvement in the common country pigs and to render them far more suitable for conversion into the kind of bacon which was in most general demand, and of course realised the highest price. For the beginning of the vast improvement in the Irish pig which has followed the importation of these Large White boars, the Irish bacon curers must receive the credit, as they joined together in the purchase of these boars which were distributed in those districts from which the various factories drew their supplies of fat pigs.
       A similar plan was adopted by Messrs. Harris of Calne who purchased some hundreds of boars of the Large White breed, and at first lent them on certain conditions to pig breeders, but later on resold the young boars by auction for whatever they would fetch, their object being to secure the use of these boars in order to render the farm pigs more suitable for the purposes of their trade as bacon curers.
       There may or may not be any grounds for the belief that the sire has a greater influence in the external form of the joint produce than does the dam, but this belief has also had its influence in determining breeders of cross breds to use the pure bred sire on the ordinary stock of the country, rather than the reverse way. There is no doubt that apart from the improvement in the general quality of the produce of the pure bred sire there results a general uniformity of the young stock, which is a great recommendation when they are placed on the market either as stores, or when fattened for the butcher or bacon curer. This uniformity of type and character in the young stock would be more noticeable still if the buyers of the pure bred sires were to continue their purchases from the same herds, providing that the owners of them were sufficiently careful in avoiding incestuous breeding.
       So many people appear to be content with the knowledge that the sire which they are purchasing has a recorded pedigree and is a pure bred sire eligible for entry in the herd book of its breed, but they forget that it is possible in the crossing of two pedigree animals of a similar breed to obtain as great a mixture of blood and points as in the mating of two cross-breds or two come-by-chances. Uniformity in a herd, stud, or flock can only be rendered comparatively certain by the continued use of sires of similar breeding. In making a compound, its character is determined by the proportion of the various ingredients used in its manufacture. So it is in the breeding of stock, those points which are most predominant in proportion in the blood of the sire and dam will, on the average, be represented in an equal degree in the joint produce. This it is which renders so impressive a sire which is descended from closely bred parents. Each of its forbears has handed down a proportion of its own particular characteristics so that the larger the number of animals amongst its forbears which possessed these particular points the greater the certainty of their being possessed by the produce. The meaning of this may be made more clear by pointing out that the result of the mixing together of various mixtures will depend entirely on the proportion of the substances used in the manufacture or compounding of those mixtures. In each animal is embodied the characteristics of its forbears.
       There exists generally an opinion that the produce of two parents of distinct breeds, or as it is termed a first cross is commonly superior to a pure bred of either of the two breeds represented by the parents. It is difficult to discover the cause of this, if it be a fact. If one of the parents were deficient in stamina the produce might conceivably be more robust, and it might also occasionally happen that the mixture of the qualities or properties possessed by the parents would result in improvement, as happens when a distinct new breed is originated; but as a rule the good and the bad qualities of the produce from the mating of two animals of diverse breeds are in direct proportion to the qualities possessed by the parents.
       The mere mixing of the blood of two animals differently bred cannot increase the good or bad properties, but the combination might possibly result in a blend more suitable for the purpose in hand.
       Another claim commonly made for the crossing of animals is that the risk of that delicacy of constitution which they assert is far too common amongst pure bred animals, and is due to close breeding, is hereby avoided. It must be admitted that in times past there was a certain amount of cause for this complaint of want of constitution amongst pedigree animals, but the cause has been considerably if not entirely removed by the more careful recording of the breeding, and by the more drastic screening out of any animals suspected of delicacy of constitution.
       The buyers of pure bred animals for crossing purposes have also become more careful in their selection. They have ceased to imagine that because the owner of certain animals most of which he has purchased is successful in winning prizes at the chief agricultural shows, the whole of the animals in his stud, herd, or flock must be of equal excellence or at all events sufficiently good for the production of profitable commercial stock. Action on this mistaken belief has led to much disappointment in the past, since the home bred animals may have been of totally different blood from those which have won prizes, and further they may not be inbred for a sufficiently long time on distinct lines to render them prepotent enough to impress their good qualities on their produce.
       Amongst the objections made to cross-breeding is the heavy cost of replacing the breeding stock, as to obtain a first cross, a succession of sires and dams must be purchased. Many persons meet this difficulty by merely buying sires of a breed similar to the first used, but then the produce ceases to be cross-breds and become grades until such time as by the use of a certain number of sires of a similar breed the produce become eligible for entry in the herd book of the sires which have been continuously used. This system of breeding insures a greater uniformity in the produce providing that the sires selected are of similar breeding, type, and character, than even by the system of crossing sire and dam of two pure breeds.
       The risk attending too close breeding as in the breeding of pure breds is also avoided provided that the herd from which the sires are bought is sufficiently large to furnish a change of blood, yet of similar breeding.
       No one possessing a knowledge of the ordinary farm stock of the country will for one moment deny that there is still vast room for improvement in our live stock, and particularly in our pigs, and it is equally the fact that our Government has not shown a readiness equal to that of some foreign Governments, and even of the authorities in some of our colonies to assist farmers in obtaining the use of improved sires. Take Canada as an instance. For years the Dominion Live Stock Branch has been purchasing and delivering free into districts needing them, male animals for the use of farmers and stock owners free, save stallions, for which a covering fee has to be paid sufficient to cover the insurance of the stallion. The other important condition which relates to all the sires provided by the authorities is that the cost of maintenance shall be paid by the Local Association which has the management of the sire and the arrangement of its services.
       Another noticeable point is that all the sires allocated to the various districts are Canadian bred, and so far as is possible are purchased in the province in which they are to be located. The object is undoubtedly to encourage in Canada the breeding of pure bred animals and may thus far be considered satisfactory, but it is acting on an assumption which may not be justified that there exists in the Dominion a sufficiency of stock equal in quality and breeding to those which it may be possible to import.
       Within the past three or four years our Board of Agriculture have taken some steps to assist our farmers to improve their stock. The assistance has taken the form of offering premiums of fixed amounts to private persons or associations who hired or purchased approved stallions, bulls, and boars which were placed at fixed fees at the service of the stock of the public. Already great benefit has been derived from the use of the stallions and bulls, and this to a far greater extent than in the pigs, as owing to an unfortunate condition which was attempted to be enforced as to the formation of pig clubs and impracticable conditions the number of boars located in the country has been much smaller than would have been had the conditions at present in force been adopted at the initiation of the scheme.
       The boar conditions are now of a similar character to those in force from the first with regard to stallions and bulls. In addition to the supply of male animals at comparatively low fees an attempt has been made to assist in the recording of the milk yield of cows, a matter of the highest importance. If only this could be extended to sows there would soon cease to be cause for the far too common complaint of the owners of sows of certain breeds of pedigree pigs, as to the limited quantity of milk which is provided by the sows for their litters of pigs. _