Part 8
After the breeder has successfully established his flock, and given them an excellent character, he soon encounters a serious evil. He must "breed in-and-in," as it is called--that is, interbreed between animals more or less nearly related in blood--or he must seek rams from other flocks, at the risk of losing or changing the distinctive character of his flock, hitherto so carefully sought, and built up with so much painstaking. The opponents of in-and-in breeding contend that it renders diseases and all other defects hereditary, and that it tends to decrease of size, debility, and a general breaking up of the constitution. Its defenders, on the other hand, insist that, if the parents are perfectly healthy, this mode does not, of itself, tend to any diminution of healthfulness in the offspring; and they likewise claim--which must be conceded--that it enables the skilful breeder much more rapidly to bring his flock to a particular standard or model, and to keep it there much more easily--unless it be true that, in course of time, they will dwindle and grow feeble.
So far as the effect on the constitution is concerned, both positions may be, to a certain extent, true. But it is, perhaps, difficult always to decide with certainty when an animal is not only free from disease, but from all tendency or predisposition towards it. A brother or sister may be apparently healthy--may be actually so--but may still possess a peculiarity of individual conformation which, under certain circumstances, will manifest itself. If these circumstances do not chance to occur, they may live until old age, apparently possessing a robust constitution. If tried together, their offspring--by a rule already laid down--will possess this individual tendency in a double degree. If the ram be interbred with sisters, half-sisters, daughters, granddaughters, etc., for several generations, the predisposition toward a particular disease--in the first place slight, now strong, and constantly growing stronger--will pervade, and become radically incorporated into, the constitution of the whole flock. The first time the requisite exciting causes are brought to bear, the disease breaks out, and, under such circumstances, with peculiar severity and malignancy. If it be of a fatal character, the flock is rapidly swept away; if not, it becomes chronic, or periodical at frequently recurring intervals. The same remarks apply, in part, to those defects of the outward form which do not at first, from their slightness, attract the notice of the ordinary breeder. They are rapidly increased until, almost before thought of by the owner, they destroy the value of the sheep. That such are the common effects of in-and-in breeding, with such skill as it is commonly conducted, all know who have given attention to the subject; and for these reasons the system is regarded with decided disapprobation and repugnance by nine out of ten of the best practical farmers.
The sheep-breeder can, however, avoid the effects of in-and-in breeding, and at the same time preserve the character of his flock, by seeking rams of the same breed, possessing, as nearly as possible, _the characteristics which he wishes to preserve in his own flock_. If this rule is neglected--if he draws indiscriminately from all the different varieties or families of a breed--some large, and some small--some long-woolled, and some short-woolled--some medium, and some superfine in quality--some tall, and some squatty--some crusted over with black gum, and some entirely free from it--breeding will become a mere matter of hap-hazard, and no certain or uniform results can be expected. So many varieties cannot be fused into one for a number of generations--as is evidenced by the want of uniformity in the Rambouillet flock, which was commenced by a promiscuous admixture of all the Spanish families; and it not merely happens, as between certain classes of Saxons, that particular families can never be successfully amalgamated.
If, however, the breeder has reached no satisfactory standard--if his sheep are deficient in the requisites which he desires--he is still to adhere to the breed--_provided the desired requisites are characteristic of the breed he possesses_--and select better animals to improve his own inferior ones. If he has, for instance, an inferior flock of South-Downs, and wishes to obtain the qualities of the best Down dams, he should seek for the best rams of that breed. But if he wishes to obtain qualities _not characteristic of the breed he possesses_, he must cross with a breed which does possess them. If the possessor of South-Downs wishes to convert them into a fine-woolled sheep similar to the Merino, he should cross his flock steadily with Merino rams--constantly increasing the amount of Merino, and diminishing the amount of South-Down blood. To effect the same result, he would take the same course with the common sheep of the country, or with any other coarse race.
There are those, who, forgetting that some of the finest varieties now in existence, of several kinds of domestic animals, are the result of crosses--bitterly inveigh against the practice of crossing, under any and all circumstances. It is, it must be admitted, an unqualified absurdity, as frequently conducted--as, for example, an attempt to unite the fleece of a Merino and the carcass of a Leicester, by crosses between those breeds; but, under the limitations already laid down, and with the objects specified as legitimate ones, this objection to crossing savors of the most profound prejudice, or the most unblushing quackery. It is neither convenient, nor within the means of every man wishing to start a flock of sheep, to commence exclusively with full-bloods. With a few to breed rams from, and to begin a full-blood stock, the breeder will find it his best policy to purchase the best common sheep of his country, and gradually grade them up with Merino rams. In selecting the ewes, good shape, fair size, and a robust constitution, are the main points--the little difference in the quality of the common sheep's wool being of no consequence. For their wool, they are to look to the Merino; but good form and constitution they can and ought to possess, so as not to entail deep-rooted and entirely unnecessary evils on their progeny.
Satisfactory results have followed crossing a Down ram--small, compact, exceedingly beautiful, fine and even fleeced--with large-sized Merino ewes. The half-blood ewes were then bred to a Merino ram, and also their female progeny, and so on. The South-Downs, from a disposition to take on fat, manifested themselves, to a perceptible extent, in every generation, and the wool of many of the sheep in the third generation--seven-eighths blood Merino, and one-eighth blood Down--was very even, and equal to medium, and some of them to good medium Merino. Their fleeces were lighter than the full-blood Merinos, but increased in weight with each succeeding cross back toward the latter. The mutton of the first, and even of the second cross was of a beautiful flavor, and retained, to the last, some of the superiority of South-Down mutton.
Results are also noted of breeding Leicester ewes--taking one cross of the blood, as in the preceding case--toward the Merino. The mongrels, to the second generation--beyond which they were not bred--were about midway between the parent stock in size--with wool shorter, but far more fine and compact than the Leicester--their fleeces about the same weight, five pounds--and, altogether, they were a showy and profitable sheep, and well calculated to please the mass of farmers. Their fleeces, however, lacked evenness, their thighs remaining disproportionately coarser and heavy.
A difference of opinion exists in relation to the number of crosses necessary before it is proper to breed from a mongrel ram. Some high authorities assert that it does not admit of the slightest doubt that a Merino, in the fourth generation, from even the worst-woolled ones, is in every respect equal to the stock of the sire--that no difference need to be made in the choice of a ram, whether he is a full-blood, or a fifteen-sixteenths--and that, however coarse the fleece of the parent ewe may have been, the progeny in the fourth generation will not show it.
Others, however--while admitting that the only value of blood or pedigree, in breeding, is to insure the hereditary transmission of the properties of the parent to the offspring, and that, as soon as a mongrel reaches the point where he stamps his characteristics on the progeny, with the same certainty that a full-blood does, he is equally valuable, provided he is, individually, as perfect an animal--contend that this cannot be depended upon, with any certainty, in rams of the fourth Merino cross. They assert that the offspring of such crosses invariably lack the style and perfection of thorough-bred flocks. The sixth, seventh, or eighth cross might be generally, and the last, perhaps, almost invariably, as good as pure-blood rams; yet pure blood is a fixed standard, and were every breeder to think himself at liberty to depart from it in his rams, each one more or less, according to his judgment or caprice, the whole blood of the country would become adulterated. No man, assuredly, can be authorized to sell a ram of any cross, whether the tenth, or even the twentieth, as a full-blood.
It is of the utmost importance for those _commencing_ flocks, either of full-bloods, or by crossing, to select the choicest rams. A grown ram may, by methods which will hereafter be described, be made to serve from one hundred to one hundred and fifty ewes in a season. A good Merino ram will, moderately speaking, add more than a pound of wool to the fleece of the dam, or every lamb got by it, from a common-woolled ewe--that is, if the ewe at three years old sheared three pounds of wool, the lamb at the same age will shear four. This would give one hundred or one hundred and fifty pounds of wool for the use of a ram for a single season; and every lamb subsequently got by him adds a pound to this amount. Many a ram gets, during his life, eight hundred or one thousand lambs. Nor is the extra amount of wool all. He gets from eight hundred to one thousand half-blooded sheep, worth double their dams, and ready to be made the basis of another and higher stride in improvement. A good ram, then, is as important and, it may be, quite as valuable an animal as a good farm-horse stallion. When the number of a ram's progeny are taken into consideration, and when it is seen over what an immense extent, even in his own direct offspring, his good or bad qualities are to be perpetuated, the folly of that economy which would select an inferior animal is sufficiently obvious.
It will be found the best economy in starting a flock, where the proper flocks from which to draw rams are not convenient, to purchase several of the same breed, of course, but _of different strains of blood_. Thus ram No. 2 can be put on the offspring of No. 1, and the reverse; No. 3 can be put on the offspring of both, and both upon the offspring of No. 3. The changes which can be rung on three distinct strains of blood, without in-and-in breeding close enough to be attended with any considerable danger, are innumerable.
The brother and sister, it will be born in mind, are of the same blood; the father and daughter, half; the father and granddaughter, one-fourth; the father and great-granddaughter, one-eighth; and so on. Breeding between animals possessing one-eighth of the same blood, would not be considered very close breeding; and it is not unusual, in rugged, well-formed families, to breed between those possessing one-fourth of the same blood.
If, however, these rams of different strains are brought promiscuously, without reference to similarity of characteristics, there may, and probably will, be difference between them; and it might require time and skill to give a flock descended from them a proper uniformity of character. Those who breed rams for sale should be prepared to furnish different strains of blood, with the necessary individual and family uniformity.
GENERAL PRINCIPLES OF BREEDING.
Some few suggestions upon the general principles to be observed in breeding may not be superfluous here, referring the reader, who is disposed to investigate this subject in detail, to its full discussion in the author's treatise upon "Cattle and their Diseases."
As illustrative of the importance of _breeding only from the best_, taking care to avoid structural defects, and especially to secure freedom from _hereditary diseases_, since both defects and diseases appear to be more easily transmissible than desirable qualities, it may be remarked that scrofula is not uncommon among sheep, and presents itself in various forms. Sometimes it is connected with consumption; sometimes it affects the viscera of the abdomen, and particularly the mesenteric glands, in a manner similar to consumption in the lungs. The scrofulous taint has been known to be so strong as to affect the f[oe]tus, and lambs have occasionally been dropped with it; but much oftener they show it at an early age, and any affected in this way are liable to fall an easy prey to any ordinary or prevalent disease, which develops in such with unusual severity. Sheep are also liable to several diseases of the brain, and of the respiratory and digestive organs. Epilepsy, or "fits," and rheumatism sometimes occur.
The breeder's aim should be to grasp and _render permanent_, and increase so far as practicable, _every variation for the better_, and to reject for breeding purposes such as show a downward tendency. A remarkable instance of the success which has often attended the well-directed efforts of intelligent breeders, is furnished in the new Mauchamp-Merino sheep, which originated in a single animal--a product of the law of variation--and which, by skilful breeding and selection, has become an established breed of a peculiar type, and possessing valuable properties. Samples of the wool of these sheep were shown at the great exhibition in London, in 1851, as well as at the subsequent great agricultural exhibition at Paris, and attracted much attention.
This breed was originated by Mons. J. L. Graux. In 1828, a Merino ewe produced a peculiar ram lamb, having a different shape from the ordinary Merino, and possessing wool singularly long, straight, and silky. Two years afterward, Mr. Graux obtained by this ram one ram and one ewe, having the silky character of wool. Among the produce of the ensuing year were four rams and one ewe with similar fleeces; and in 1833, there were rams enough of the new sort to serve the whole flock of ewes. In each subsequent year, the lambs were of two kinds; one possessing the curled, elastic wool of the old Merinos, only a little longer and finer, and the other like the new breed. At last, the skilful breeder obtained a flock containing the fine, silky fleece with a smaller breed, broader flanks, and more capacious chest; and several flocks being crossed with the Mauchamp variety, the Mauchamp-Merino breed is the result.
The pure Mauchamp wool is remarkable for its qualities as a combing-wool, owing to the strength, as well as the length and fineness of the fibre. It is found of great value by the manufacturers of Cashmere shawls, and similar goods, being second only to the true Cashmere fleece, in the fine, flexible delicacy of the fibre; and when in combination with Cashmere wool, imparting strength and consistency. The quantity of this wool has since become as great as that from ordinary Merinos, or greater, while its quality commands twenty-five per cent. higher price in the French market. Breeders, certainly, cannot watch too closely any accidental peculiarity of conformation or characteristic in their flocks.
_The apparent influence of the male_ first having fruitful intercourse with a female, _upon her subsequent offspring by other males_, has been noticed by various writers. The following well-authenticated instances are in point:
A small flock of ewes, belonging to Dr. W. Wells, in the island of Granada, was served by a ram procured for the purpose. The ewes were all white and woolly; the ram was quite different, being of a chocolate color, and hairy like a goat. The progeny were, of course, crosses, but bore a strong resemblance to the male parent. The next season, Dr. Wells obtained a ram of precisely the same breed as the ewes; but the progeny showed distinct marks of resemblance to the former ram, in color and covering. The same thing occurred on neighboring estates, under like circumstances.
Six very superior pure-bred black-faced horned ewes, belonging to Mr. H. Shaw, of Leochel, Cushnie, were served by a white-faced hornless Leicester ram. The lambs were crosses. The next year they were served by a ram of exactly the same breed as the ewes themselves, and their lambs were, without an exception, hornless and brownish in the face, instead of being black and horned. The third year they were again served by a superior ram of their own breed; and again the lambs were mongrels, but showed less of the Leicester characteristics than before; and Mr. Shaw at last parted from these fine ewes without obtaining a single pure-bred lamb.
To account for this result--seemingly regarded by most physiologists as inexplicable--Mr. James McGillivray, V. S., of Huntley, has offered an explanation, which has received the sanction of a number of competent writers. His theory is, that when a pure animal of any breed has been pregnant by an animal of a different breed, such pregnant animal _is a cross ever after_, the purity of her blood being lost, in consequence of her connection with the foreign animal, and herself becoming a cross forever, incapable of producing a pure calf of any breed.
To cross, _merely for the sake of crossing_, to do so without that care and vigilance which are highly essential, is a practice which cannot be too much condemned, being, in fact, a national evil, if pushed to such an extent as to do away with a useful breed of animals, and establish a generation of mongrels in their place--a result which has followed in numerous instances amongst every breed of animals.
The principal use of crossing is to raise animals for the butcher. The male, being generally an animal of a superior breed, and of a vigorous nature, almost invariably stamps his external form, size, and muscular development on the offspring, which thus bear a strong resemblance to him; while their internal nature, derived from the dam, well adapts them to the locality, as well as to the treatment to which their dams have been accustomed.
With sheep, where the peculiarities of the soil, as regards the goodness of feed, and exposure to the severities of the weather, often prevent the introduction of an improved breed, the value of using a new and superior ram is often very considerable; and the weight of mutton is thereby materially increased, without its quality being impaired, while earlier maturity is at the same time obtained. It involves, however, more systematic attention than most farmers usually like to bestow, for it is necessary to employ a different ram for each purpose; that is, a native ram, for a portion of the ewes to keep up the purity of the breed, and a foreign ram, to raise the improved cross-bred animals for felting, either as lambs or sheep. This plan is adopted by many breeders of Leicester sheep, who thus employ South-Down rams to improve the quality of the mutton.
One inconvenience attending this plan is the necessity of fattening the maiden ewes as well as the wethers. They may, however, be disposed of as fat lambs, or the practice of spaying (fully explained in "Cattle and their Diseases") might be adopted, so as to increase the felting disposition of the animal. Crossing, therefore, should be adopted with the greatest caution and skill, where the object is to improve the breed of animals. It should never be practised carelessly or capriciously, but it may be advantageously pursued, with a view to raising superior and profitable animals for the butcher. For the latter purpose, it is generally advisable to use males of a larger breed, provided they possess a disposition to fatten; yet, in such cases, it is of importance that the _pelvis_ of the female should be wide and capacious, so that no injury may arise in lambing, in consequence of the increased size of the heads of the lambs. The shape of the ram's head should be studied for the same reason.
In crossing, however, for the purpose of establishing a new breed, the size of the male must give way to other more important considerations; although it will still be desirable to use a large female of the breed which is sought to be improved. Thus, the South-Downs have vastly improved the larger Hampshires, and the Leicester, the huge Lincolns and the Cotswolds.
USE OF RAMS.
Merino rams are frequently used from the first to the tenth year, and even longer. The lambs of very old rams are commonly supposed not to be as those of middle-aged ones; though where rams have not been overtasked, and have been properly fed, little if any difference is discoverable in their progeny by reason of their sire's age. A ram lamb should not be used, as it retards his growth, injures his form, and, in many instances, permanently impairs his vigor and courage. A yearling may run with thirty ewes, a two-year-old with from forty to fifty, and a three-year-old with from fifty to sixty; while some very powerful, mature rams will serve seventy or eighty. Fifty, however, is enough, where they _run with_ the ewes. It is well settled that an impoverished and overtasked animal does not transmit his individual properties so decidedly to his offspring as does one in full vigor.
Rams, of course, are not to be selected for ewes by mere chance, but according as their qualities may improve those of the ewes. It may not be superfluous, though seemingly a repetition, to state that a good ewe flock should exhibit these characteristics: _strong bone_, supporting a roomy frame, affording space for a large development of flesh; _abundance of wool of a good quality_, keeping the ewes warm in inclement weather, and insuring profit to the breeder; _a disposition to fatten early_, enabling the breeder readily to get rid of his sheep selected for the butcher; and _a prolific tendency_, increasing the flock rapidly, and being also a source of profit. Every one of these properties is advantageous in itself; but when all are combined in the same individuals of a flock, that flock is in a high state of perfection. In selecting rams, it should be observed whether or not they possess one or more of those qualities in which the ewes may be deficient, in which case their union with the ewes will produce in the progeny a higher degree of perfection than is to be found in the ewes themselves, and such a result will improve the state of the future ewe-flock; but, on the contrary, if the ewes are superior in all points to the rams, then, of course, the use of such will only serve to deteriorate the future ewe-flock.
Several rams running in the same flock excite each other to an unnatural and unnecessary activity, besides injuring each other by constant blows. It is, in every point of view, bad husbandry, where it can be avoided, and, as customarily managed, is destructive to every thing like careful and judicious breeding. The nice adaptation which the male should possess to the female is out of the question where half a dozen or more rams are running promiscuously with two or three hundred ewes.