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Pig: Breeding, Rearing, and Marketing, The
Chapter 10. Weaning Pigs
Sanders Spencer
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       _ CHAPTER X. WEANING PIGS
       There are few points in connection with the breeding and feeding of pigs on which there is a greater diversity of opinion and practice than on the question of the weaning of the young pigs.
       For instance, take the age at which it is most satisfactory to take the pigs off the sow. This practice varies greatly in different districts, and even in the same district where one would naturally suppose that the determining influences would be similar weaning at five or six weeks old.
       One pig breeder will declare that a little pig of five or six weeks old should be and is able to support itself alone, and will act accordingly. Should perchance a litter weaned thus early cease to grow the excuses made will be various.
       The weather is at fault, it is either too hot or too cold, or the sharps, etc., on which they have been fed were not good or sweet, that the sow's milk was not sufficiently plentiful, or it was wanting in nutriment. In fact, any excuse will be made rather than the actual cause admitted.
       In far too many instances the real reason for the want of thrift on the part of the young pigs taken from their mother when they are not more than five or six weeks old is that their digestive organs are not sufficiently developed as to enable them to digest enough food to nourish them properly.
       Another excuse often made for what we consider to be undue haste in weaning young pigs is the alleged desire of the owner not to waste the time of the sow. He is anxious to have her served again and hasten the arrival of the next litter.
       Occasionally it is found to be unnecessary to wean the pigs for this purpose as the sow will come in heat and can be served by the boar, but if she should become in pig the result will be much the same so far as the pigs are concerned, since as soon as the sow has conceived the milk will promptly cease or become very reduced in quantity and quality.
       On the other hand, if the sow does not stand to the boar time may be wasted. It is most unlikely that the sow will again become in heat for some three weeks, whereas this almost always occurs within a few days of the weaning of the litter of pigs.
       Then another extreme, and one which is practised by some pig breeders, is to allow the young pigs to remain on the sow until the former are from ten to twelve weeks old. It is claimed for this practice that the young pigs grow much faster when left on the sow than when weaned, and that less food is consumed for a live weight increase from a given quantity of food. Also, it is said that food of more inferior kind can be fed to the sow than could be fed to the pigs if they were weaned, and thus the sow and litter are kept at less expense, and that if the pigs are not weaned until nearly three months, the milk of the sow will have gradually ceased to flow, and the pigs will not miss the help from their dam. Their digestive organs will then have become sufficiently developed to enable them to make the best use of the food given to them, and they will sustain no check in thrift or growth when they are weaned.
       In this question of weaning pigs the good old fashioned plan of following the middle course will probably be found to be the best. Anyway, it was the one which we followed for a great number of years and found the results generally satisfactory for the following among other reasons.
       As a breeder of pure bred pigs for sale as boars or yelts for breeding purposes, we were naturally anxious to give the pigs a good start in life so that we should be able to sell them as quickly as possible, and that they should thrive when they came into the possession of their new owners, and thus prove the best possible advertisement of our herds. As a rule we found that if the pigs were allowed to remain on the sows until they were some eight weeks old they were quite strong enough to fend for themselves, that by gradually increasing the length of time which the sow was allowed to remain from the pigs, the latter became accustomed to exist without the mother's milk, and as the milk of the sow naturally dried up when the pigs partially ceased to withdraw it, no trouble was experienced with inflamed udders as is usually or commonly the case when the pigs are suddenly weaned from a sow which is in full milk.
       There is also another advantage apart from that to the sow and pigs, it is that the sow will almost invariably come in heat within three or four days of the weaning, and with the best possible chance of becoming in pig.
       Some pig keepers are more inclined to wean their litter of pigs at an early age, and then if the sow be low in condition to baulk her at the first time of [oe]strum. There are objections to this--one of them is that there is frequently a difficulty in getting the sow to conceive after she has been baulked. Why this should be so we have not been able to ascertain. We only record what we know to be a fact.
       In our opinion this difficulty is one of the strongest points in favour of the practice of allowing the young pigs of a sow with her first litter, or of an old sow which has become low in condition (either from having had too many pigs left on her, or from other natural cause), to remain on the sow for a longer period than about eight weeks. Some persons will keep the pigs on the sow until they are nearly three months old in the belief that both sow and pigs are benefited, and that the pigs can be kept quite as cheaply if not more so when unweaned than weaned. They also claim that the sow is so much stronger and better fitted to prepare for another litter. Experiments have been carried out in the United States which go far to prove that the first of these two claims is founded on fact; and it has further been demonstrated that certain foods can be fed to the sow without affecting the thrift and health of the pigs which could not with safety be fed to the latter direct, yet when fed through the sow the pigs will thrive on the milk produced therefrom. It is entirely a question of the cost of a rest for the sow during the extra two or three weeks, and the benefit to the sow and her pigs.
       One occasionally sees in the press a claim for what is considered to be a great achievement in that some one has bred three litters of pigs from one sow within the year. There really is something wonderful in this since of the fifty-two weeks constituting a year, the sow would be carrying her pigs some forty-eight weeks. This would allow only four weeks for the two litters of pigs to be suckled, and this would also include the few days between the pigs being weaned and the sow coming in heat. Apart from the natural difficulty of successfully breeding three litters of pigs from one sow within twelve months, there exists a far greater possibility of loss rather than of gain from unduly hurrying on the arrival of each litter of pigs from a sow, especially of the profitable kind of sow.
       Some forty years since when Small Whites, Small Blacks, and short thick Berkshires were fashionable, the number of pigs in each litter was few, and the number reared still fewer, owing to the limited quantity of milk furnished by the sow. Now, the Large Black, the Large White, the Middle White, the Lincolnshire Curly Coat, the old Gloucester Spots, the Tamworth, the Cumberland, and even the sows of most of the local breeds of pigs are expected to rear nine or ten pigs each litter. Even if it were possible for a sow to bring forth three litters within the year, she could not possibly do justice to them either before or after the piglings arrived in this world; and further, the life of such a sow would of necessity be a short one. It must not be forgotten that in the production of each litter of pigs the sow is compelled to manufacture from 20 to 30 lbs. of flesh, skin, hair, etc., which together constitute the newly farrowed pig, and very frequently this has to be accomplished on a far too limited supply of suitable food. _