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Pig: Breeding, Rearing, and Marketing, The
Chapter 7. The Sow's Udder
Sanders Spencer
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       _ CHAPTER VII. THE SOW'S UDDER
       One of the most important points in connection with the reproduction of the species of our various domestic animals is the provision of a full supply of milk for the young in the early portion of their existence. Nature herself has set us a good example in a duplicated source of milk supply even amongst animals which usually produce only one animal at a birth. If this duplication be necessary under such conditions, it must be imperative on us to select those sow pigs which are intended for breeding pigs which possess a well-formed udder, having a full supply of teats, and these of good shape and properly placed on the belly of the sow. Not only is this necessary to ensure the rearing of a fairly numerous litter of pigs in a satisfactory manner, but it is held that the number of teats possessed by a sow indicates to a remarkable extent the probable degree of prolificacy of the sow. One can readily understand that nature would not be likely to endow a sow with the power to produce a larger number of young at each birth than she would be able to rear. Of course it may be said that the sow of the present day is not as nature first made her, in that, by selection and by feeding, the number of pigs produced at each birth is now so much larger than the litters of the wild sows, which have some seven or eight teats and farrow at each litter a similar number of pigs. On the other hand, neither the number of teats nor of the young is fixed either in the domesticated sow, or the sow in a wild state, so that by continued selection we are able to permanently increase, within limits, the production of larger litters and the increased supply of milk for their sustenance when young.
       The provision of a suitable udder is even of more importance with the domesticated than with the sow running wild, since the latter produces each year one litter only, and that in the season of the year when the young are less dependent on their dams; whereas the domesticated sow is expected to rear at least two litters per year, and frequently owing to want of care on the part of the owner the young pigs are farrowed at the most unfavourable time of the year.
       Apart from the provision of a certain number of teats there is another point to be considered, the power of the sow to produce milk enough to satisfy the given number of pigs. This of course varies with each family or tribe of pigs, and even with the various members in it, so that to obtain the best results selection must be made of the produce of those sows which give the largest quantity of the most nutritious milk. There exists amongst pig keepers a difference of opinion as to the number of pigs each sow should be allowed to rear, probably the average of this number would be ten for a mature sow, and seven or eight for a first litter. If so, the selected sow pig should possess twelve teats, as frequently one of these may not give a full supply of milk from either natural or accidental causes. The teats should be regular in size and form. It is not uncommon to find one or more of the teats of a sow much smaller in size than the others. These smaller teats will produce a reduced quantity of milk, so that the pigling which is unfortunate enough to decide on making this small teat its very own--and each pigling is confined by the others to its own special teat--is certain to be less well developed than its brothers and sisters, even if it should succeed in surviving.
       The necessity for the teats being placed equidistant the one from the other arises from the desirability of each pig having room to suck comfortably. Should two of the teats be closely placed the two pigs will probably fight, when not only will sores be caused on the cheeks of the pigs, but the milk in the teats not properly drawn will gradually cease to flow.
       Another point of great importance is that the teats should commence as near as possible to the fore legs--this for two reasons: it gives more room for the pigs to suck as they grow larger; the other and more important one is that the teats most forward on the udder of the sow produce the larger quantity of milk, or milk of a better quality. It will be almost invariably found that the pigs sucking the foremost teats thrive the best.
       It is advisable to avoid the selection of a female pig for breeding purposes from a sow which has large and coarse teats, as these invariably accompany coarseness of skin, bone, hair, and flesh, this in turn affects the sale value of the carcase. It will also be found that those sows with a neat and compact udder, with fine teats, will give more milk and a better quality than sows possessing a coarse and flabby udder.
       Another weakness to be avoided when selecting a sow pig for breeding purposes is that which is commonly termed a blind teat, since it is undoubtedly hereditary in addition to being useless for the purpose of rearing pigs. The normal teat projects boldly from the udder, whereas the blind teat is almost flat or on a level with the udder. In appearance it resembles a ring of skin with a depressed nipple in its centre. At the time of parturition the blind teat contains milk to the same extent as do the other teats, but it promptly dries up since it is impossible for the little pigs to extract the milk from it since the nipple recedes as soon as the pigling attempts to clasp it with its lips and tongue, instead of becoming more extended so that the little pig can suck the milk from it.
       An ideal udder can be briefly described as one possessing at least twelve fully developed teats, the more the better--these should commence from a point as near the fore legs of the sow as possible, and be placed as nearly as possible an equal distance the one from the other.
       Some persons hold that large teats and much loose skin are sure indications that the sow has proved to be a good milker. This is a mistaken view; it is with sows as with cows, the most prolific milkers are those with well formed and soft udders which almost disappear when the lactation period has passed. _