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CROSSING. By crossing-amalgamation of blood or races—in the more limited (agricultural) sense of the term, we understand the pairing of animals of different races or tribes, e. g. of the Shorthorn and Devon races of cattle. But in common practice, pairing among the kindred breeds or tribes of one race is also considered a crossing. This view is not objectionable, either, since a commixture of two different kinds of blood takes place. The productions of the crossings mentioned are called bastards, (mongrels) according to the agricultural doctrine of breeding, but in the sense of natural history, a bastard originates only from the pairing of different classes and species of animals, and is generally unfruitful, as, e. g. the bastard between the ass and zebra; but the productions obtained by the common crossing, the pairing among races, tribes and breeds, are always fruitful.
By crossing, the various properties of two or more races, tribes or breeds, may be combined and preserved in the productions originating from such. a commixture of blood. In pairing animals of a badly built race with those of a well built one, the first productions, as to their structure, must be a medium one between the two races. The same is true in respect to the earlier or later development and the useful qualities of the animals. If all the conditions of a successful crossing are secured, it becomes the means of producing a larger size, a better form, and more useful qualities of establishing a new breed pretty surely, and sooner than it can be done by in-and-in or thorough breeding.
But to cross successfully, the following points must be observed, otherwise success and final results will be problematical, or at least retarded :
1. The animals must not differ too much from 'each other, or be too heterogeneous in size and form, their anatomical proportions, or in color and qualities. If too large and small, too short and long, too high and low built animals are paired together, the productions are generally deformed, and if the color of the breeding animals is too different, an unpleasant combination of color will result, which will not assume a fixed type in the offspring, but always change. The old rules in cattle breeding, "Pair like to like," or "like paired with like produces like,” hold good here to a cer. tain extent, otherwise a crossing should never be undertaken. Now, as the many various races are very different as to form and color, so they are heterogeneous in their interior structure, which is not externally so apparent. Experience teaches that certain individual tribes, being not very heterogeneous in size and form, will not amalgamate easily or never successfully, so that their offspring will always more closely resemble the one or the other of the parent animals, and not stand, as to their forms and properties, between both. Families, kinds breeds and tribes of one race will generally commingle more readily than those of different races.
Where crosses between breeds of cattle, of which successful crosses are not yet known, are intended to be made on a large scale, prudence demands to institute at first experimental crosses, lest money, time, feed and labor be wasted.
2. The male animals to be selected for crossing, if the breeder aims at definite characteristics of the race, must possess purity of race and constancy, or an extraordinary individual power of hereditary transmission ; otherwise the results of this system of breeding will be of little value or uncertain. Animals descending from breeds or families not long established themselves, and not possessing a fixed type, will not always transmit their properties with certainty, but ancestral defects will often reappear. Bulls taken from the boundary line of a territory where a certain breed of cattle are spread, are not to be commended for crossing, because they do not possess the power of transmitting their properties with certainty, on account of their mixed blood and not fully established constancy.
As to how long it will take cattle produced by crossing to obtain a fixed type and the perfect constancy in transmission of it, an annual meeting of the Agricultural Association of Scotland held at Inverness some years ago, gave the following interesting data :
Harvey, of Tillygreig, said that in breeding Durham cattle, a case occurred to him where a bull-calf had been dropped in the eighth generation which, on account of its black and white color, could not be registered as a Shorthorn in the herd-book. Grant Duff, of Eden, one of the most promipent breeders in Scotland, stated that he prcduced a perfect hornless Angus bull by the sixth crossing of the hornless Angus cattle with Shorthorn bulls. A Mr. Horne, and several other rational breeders gave it as their opinion that a head of cattle with only one crossing in its pedigree, could never be acknowledged as a full blood animal; and while others did not venture stating their views as to when cattle crossed with Shorthorn bulls would possess so much of Shorthorn blood as to be considered fullblood Shorthorn cattle, all present agreed that purity of blood in the male animals used for crossing is the chief condition for a successful and proper crossing, and that since the first cross excells all the following ones in valuable qualities, a second crossing should be attempted in exceptional cases only.
3. The food for cattle to be formed into a new tribe, must not differ too much in quality and quantity from that given to the animals from among which the breeding animals were chosen; for otherwise the useful qualities aimed at and found in that tribe from among which the breeding bulls were selected, can not be fully developed. The same rule applies to the manner of keeping and using the animals. He who believes to be able to
make small cattle heavier and better with scanty feeding, by merely crossing them with bulls of a larger kind, of better milking or fattening qualities—which absolutely demand a better feeding-will surely wait in vain for permanently favorable results from his procedure, but will injure his original stock instead of improving them.
Crosses may be instituted for various purposes. They may be : 1. A regular and constant crossing, the object of which is to establish a
In cases where the present stock does not meet the demands of the owners, and the necessary means for procuring a new stock are wanting, the breeders, if they always exclude their own bulls from breeding, procure bulls from the tribe with which the crosses were commenced, may gradually exterminate the original type and supplant the tribe introduced, even to a small fraction of its totality.
2. A merely transient cross. If an in-and-in bred tribe lack the one or the other desirable qualities in regard to form, size or usefulness, &c., which are hard to acquire, or only after too long a period of time by in-and-in breeding, these properties may often be acquired safer and sooner by crossing them for one, two, or three generations with suitable bulls of another
3. A variable cross.—If certain points in respect to form, maturity of development, or useful qualities, can not be attained by an amalgamation of two different races, it may sometimes be accomplished by again crossing the tribe already mixed with a third race, or by a combination of three kinds of blood. This method has long since been pursued by the Englisb, and in more recent times adapted by the French; extraordinary success has resulted from it which could not have been attained by a single admixture of blood. As early as 1856, at the great cattle show in Paris, excellent productions of such double crossing were exhibited; for instance: of the Durbam, Swytz, and Normandy races. It was attempted to improve the Normandy race by Swytz blood, and in order to obtain fine bones, a rapid development, and better fattening qualities, an additional crossing with Durham bulls was resorted to. In France such double crosses have been instituted with the Durham, Holland, and Flemish races, and also with the Durbam, Ayreshire and Breton races. Of course, the last mentioned double crosses requires a thorough knowledge of the races, and great caution as to the selection of the animals and the length of time for which it is to be carried on; for otherwise it must prove injurious.
Finally, as to the question how long a cross once commenced is to be continued, no general answer can be given, but this depends on various influences and circumstances. If the crossed races are originally near akin (of a homogeneous nature), the object aimed at will always be accomplished within a shorter space of time. Besides, the more feeding, keeping, and use made of the animals are conformed to the natural condition of the new tribe, and the more favorable the climatic influences are, the sooner the crossing may terminate. But if the contrary is the case to a greater or less extent, it will take more time to produce even less perfect specimens, and as much longer period of time will be required to firmly establish the desired qualities in the offspring. Yet the crossing must always be continued till the productions have attained to a somewhat higher degree of improvement than was at first intended. A gradual deterioration of animals of mixed blood in their forms and qualities may generally be expected; but by pursuing the method just named, the desirable properties may be conserved for a long period of time.
The majority of rational breeders still contend that in any, even long continued crossing, a fraction of the common blood of the original tribe expressible in figures, will always remain in the improved animals, according to the amount of which reappearances of ancestral defects or back breeding may be expected in the future. The calculable process of improvement in a tribe is stated at the end of this
paper. From this it will be seen that great results may be derived from a cross on a small scale, if rationally managed, and if the necessary means for purchasing and proper feeding of suitable animals are provided. But to improve whole breeds and tribes requires very great care and a large sum of money, therefore crossing should take place to a limited extent only.
Crosses instituted and managed according to rational principles, and constantly aiming at fixed objects, are very advantageous and profitable; but, on the other hand, the disadvantages resulting from senseless and irrational mixtures of blood are very great and injurious. It frequently happens from ignorance that unsuitable animals of different tribes and breeds are bred together; now as these animals are heterogeneous to each other, and possess the defects of both tribes or breeds; and furthermore, since these admixtures of blood do not receive the proper attention in the feeding, keeping, and use of the animals, worthless productions of a bad form and color, and little utility will result. Any one directing his attention to this subject can not fail to observe the numerous defective animals possessing unpleasing shades of color, all the defects possible in their form with scarcely any useful qualities. But as in such an irrational method of breeding, these half-breed animals again are paired ad libitum, or being paired to one another, the results must grow worse and worse, and thus the families, breeds, and tribes of cattle must gradually deteriorate. It is this method of crossing against which rational breeders have always contended and must still conteud for a long time. As to the ignorance alluded to, from which such a pernicious method of breeding originates, we will quote here the words of Wolstein, the venerable instructor at the Veterinary School of Vienna. In his book “On Diseases of Cattle,” 1789, he says: “The farmer only who raises grapes and vegetables is instructed in his business, but the farmer who raises cattle knows nothing. He can not distinguish the breeds and tribes; he does not know what are bastards, or improved animals, or originals, "&c.
But frequently false parsimony and unpardonable indifference are the causes of such senseless pairing, and often the finest and best tribes of cattle are thereby ruined. This ought to be severely reprimanded, since such bad examples may be followed by others. Against this method followed even for a short time, the following experiences may serve as warnings.
It has often been observed in horses, hogs, and sheep, that the first impregnation of the female determined, to a greater or less extent, the character of the ensuing progeny. In the dog cases are on record where the first impregnation evidently had an influence upon the two ensuing conceptions. These experiences have been doubted by some, from the fact that in the human family it has been observed that adulterous wives bore children resembling their legitimate husbands; hence the proverb: "The child of adultry palliates the mother's shame;" but this only goes to confirm the observations in inferior animals above stated. There have also been cases, doubted by some writers, yet positively asserted by others, where widows baving bad children by their first husband and living happy with the second, bore children by the latter strangely resembling the former.
Several special cases of the so-called infection of the cow by the first impregnation, are stated in Fuchs' Pathological Anatomy of Domestic Animals, which we will insert here.
James McGillavary, Veterinarian at Hantly, in the Aberdeen Journal, says: “When a cow of the pure Aberdeen race is covered by a Shorthorn Teeswater bull, the blood of the cow becomes the more changed, the more the calf resembles the bull, and afterwards she no longer produces a calf of pure race or blood. It is apparent that the great variety of forms in herds is chiefly owing to this admixture of blood in the cow through the first bull covering her. A cow of the Aberdeen race was covered by a bull of the pure Teeswater race, and she bore a calf being & cross between the two races. In the following year a bull of her own race was brought to her, but the calf was likewise of a mixed race, and when two years old had very long horns, although both its parents had very short horns. In 1845, another young Aberdeen cow was covered by a bull descending from a cross between a cow crossed with a Teeswater bull. She brought forth a mongrel calf; and when afterwards paired with a bull of her own race, she likewise bore a cross calf so far as to form as well as