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the movements of the animals requiring greater exertion. But animals liv. ing in level countries have less powerful extremities, not well adapted for running; even short marches will make them tired, and their breathing difficult; because their locomotion on the level soil required no great exertion of the extremities and lungs.
Heat and cold exert a great influence upon plants and animals, and, therefore, as a necessary consequence, upon the formation of particular races. Animals of the same species living in different climates often present considerable differences. In hot climates, the animals remain smaller and possess the so-called dry structure, because their organization is formed of fine compact bones and powerful muscles, but produces very little fat. Animals imported into this climate from regions of a temperate climate will change in respect to skin and hair as well as to color and instinct. In the hot climate of Cuba the cattle have thin hair and often are entirely bare, and the imported dogs have become brown and smaller. The geese and hens lay smaller eggs, (Rowlin). In Syria, the cats, rabbits and goats have very long and soft hair; in Corsica, the horses, dogs and other ani. mals become speckled; in Paraguay our domestic cat, since its importation
300 years ago, has become smaller, the trunk much thinner, the limbs more puny, the hair shorter, more glossy, thinner and lying close to the skin. It seldom pairs with freshly imported specimens. In the Paraguayan sheep the character of the Spanish sheep has wholly disappeared; they are smaller, the wool short and very rough, and the mutton lean and white, But the influence of the cold climate at far north or on high mountains is apparent in the small size and mostly compact form of the animals, a change of color, harder skin and thicker hair. The hogs of the Paramos have curley hair, and the wild cattle there, living at an elevation of 7,500 feet, have a thicker skin than those in the valleys. The African house dogs are bairless, or have thin hair only, but when transported in more northern climates, hair again appears on them after several generations.
The amount of vapor in the air and the dryness and moisture of the soil, likewise have a powerful influence. The atmosphere always contains vapors, a proper amount of which is necessary for animals. But when it is in too limited quantities, plants as well as animals, obtain too little of it, and the consequence is a too copious perspiration through the skin, but for the former, a defective development causing a want of proper nutriment for the animals. The plants and animals of moister countries and regions excel those of drier climates by their more rapid growth and larger size. Even the hair of many animals becomes coarser and rougher in wet climates; hence very fine sheep gradually lose their fineness of wool. A larger amount of moisture is necessary for cattle which thrive well in
wet climates, as is known to be the case in the countries bounded by the North Sea, and many mountains where the atmospheric precipitations are copious.
The organization of animals depends on these influences, and when they are not changed in the course of time, the external and internal characteristics of the animals must remain constant. Thus it is explained why countries enjoying the same climate have the same or at least homogeneous native animals.
But cattle transferred from one region into another where the influences are different, will immediately change their exterior and interior characteristics, and this for the better or worse, according as the new place of abode is more or less conducive to their well-being than the former; and even smaller differences of climate exert a visible influence upon animals living in a state of nature.
The original native country of animals is considered to be the natural area for their spread or propagation, allowing, of course, in its centre or at several places the most perfect development of the race in question. Such a natural area is of different extent; either it forms a contiguous territory, or is sometimes separated by intervening areas in which other races are spread. The boundaries of these areas may be divided into horizontal and vertical. The former are northern and southern, and the latter ascending, mostly pretty well defined. At the periphery or the boundary line of other regions of a different nature the perfection of the races will disappear, and the purity and beauty of the races will be impaired, and other forms origi nate, as mentioned on a preceding page.
But in their native countries the characteristics of the natural races are often the more difficult to efface through the artificial influences of feeding and keeping, the older these races are. It is scarcely possible wholly to efface all those interior and exterior characteristics, or when the attempt is successful, it is only for a short time or in individual cases, and the original soon reappears.
PRODUCTION OF ARTIFICIAL, OR SO-CALLED CULTIVATED
RACES. With the improvements in agriculture and cattle breeding, an attempt was made to establish new races; and more recently the English have in an eminent degree succeeded in producing races, or rather tribes and breeds, fully adapted to the various demands of agriculture and national economy.
Through a proper and judicious system of feeding and keeping cattle, it is almost always possible to a certain degree to protect them from the unfavorable influences of the climate, and to produce upon the same soil and under the same climatic conditions, tribes of animals of a different form and structure. By a constant system of in-and-in breeding, or more especially by a properly regulated method of crossing, or by the breeding of animals according to a definite plan; thus by a certain kind of food of a certain chemical composition, given in larger or smaller quantities, by giving more voluminous or concentrated food, in a wet and prepared, or in a dry and natural state, man may exert a very powerful influence upon the pro duction of certain definite animal forms and their useful qualities. In this respect astonishing results may be obtained within a short time, by keeping them warmer or cooler in stables, or wholly in the open air, by keeping them alternately, at the proper times, in the stable or on the pasture, and by employing all available means to establish a certain desired useful quality.
In the natural way, namely, by the uninterrupted natural influences upon the animals, new races are gradually formed only when the animals migrate into regions of a different nature, but artificial races are produced in a much shorter time, if the soil and climate are not too unfavorable to the plan pursued; for every impediment is removed, and every thing employed conducive to the development of the animals for the purpose of attaining certain desirable qualities. As the sculptor, in clay or stone, &c., forms his ideals, so likewise, the rational breeder will succeed in gradually producing animals of different forms and nature, if he is able constantly to fulfill the conditions necessary for that purpose. In this respect, the doctrine of animal production has of late justly been termed "zootechnics.” The breeder may, to a certain degree, overcome the climatic influences in producing certain animal qualities, if be persistently pursues a definite and correct system of breeding, and possesses protecting stables, suitable pastures and food and fodder. But if the one or the other factor is disregarded or entirely absent, he will be less successful; and finally, if every thing is left to nature, all the various tribes will soon present but one type, namely, that produced by the existing natural factors; for man can never overcome nature, but attain great results only when he understands her laws, knows how she works and changes, and constantly observes and follows her operations. "From this point of view, the long continued dispute may be considered as decided, as to whether the climate alone exerts its influence upon the formation of races or tribes, which many deny altogether, and are inclined to hold the formation of races to be dependent solely upon the option and action of man.
METHODS OF BREEDING.
IN-AND-IN BREEDING AMONG FAMILIES.
The term "in-and-in breeding" signifies the pairing of the nearest and nearer kin in one and the same family. · In-and-in breeding is the means of preserving unchanged, or cultivating the type of those two animals paired together at the beginning, for the reason that generally either animal transmits its peculiar qualities to its progeny, and this receives, by hereditary transmission, the qualities of both the parent animals. If the animals produced in this way, after reaching the state of maturity, are again paired exclusively with their sire or dam, and afterward the sisters and brothers, and so the following generations are again paired with one another, the original type of the stock animals must be preserved in a uniform manner, provided that external influences do not impede the growth and development of the animals.
By in-and-in breeding, if the new productions are consistently paired together, the tribe is produced, and nearly all tribes of recent times originated, or are originating in this way from a single one or several pairs. The celebrated breeder Bakewell, in founding his famous race of cattle, is said to have adopted and perfected the method of in-and-in breeding; the same plan was pursued by the brothers Collings.
Although the pairing among members of families has great advantages, yet if the pairing of the nearest member of a family is continued through several generations, or for too great a period, and the animals are not selected with proper care, this system will be found to bave corresponding disadvantages. The effects and the advantages and disadvantages of in-and-in breeding are, as yet, not fully understood, and therefore we shall enlarge somewhat on this subject. Sinclair, years ago, pointed out the ad. vantages of in-and-in breeding, but he did not deny that if it was continued too long, imbecility and barrenness were the unavoidable consequences.
That in-and-in breeding among hogs causes a decrease in their prolificacy and a poor development in their offspring, has of late been shown, especially in the breeding of English races; and still more recently Rhode, in his essay "on the nurture and use of the domestic hog,” (Greifswalde and Leipsic, 1860) says that the breeding of blood relations is very objectionable. A long continued pairing of the nearest members of families among sheep, has injurious effects, and it has even been considered to be the cause of the vertigo.
Nathusius adds to his monograph on "Shorthorn Cattle," (Berlin, Bossellman, 1857) an appendix on in-and-in breeding, or pairing of near relations, in which he states the following points in regard to his system of breeding:
“The breeding with the nearest blood relations, especially among cattle, must often be re-adopted whenever it becomes necessary to establish cer. tain qualities in breeding animals, and to produce higher degrees of improvement.
“But great precaution is required, because a long continued in-and-in breeding has often produced barrenness and debility in the offspring.
“In general, therefore, in and-in breeding should not be adopted in large herds, or among common working cattle, since among them such a minute observation of the individuals as the breeder of the improved race of ani. mals must exercise, would actually be impossible.”
Justinus, in his “Principles of Horse Breeding," says that those breeders are sadly mistaken who believe that unconditional in-and-in breeding produces more perfect animals, but, on the contrary, it becomes injurious if the breeding animals are defective. In respect to the in-and-in breeding of cattle, we append the following views : · David Low says, in his "Practical Agriculture,"_"This system has its limitation ; for nature will not conform to our combinations if they deviate too far from the usual way. It is a well-known fact that by the pairing of near relations, the volume of the bone decreases and fattening qualities increase; but on the other hand, the productions are much more delicate and subject to diseases. Therefore, if these combinations are continued with very excellent animals to a certain point, in order to insure constancy in the hereditary transmission of their qualities, we commit an act of violence against nature, if we go too far in this respect. The race possesses the ad. vantages of early maturity and of fattening sooner and more easily ; but they lose their vigor and energy, the females do not give the requisite quantity of milk for nursing their young, and the males lose their procreative power and capability of propagating the race. Many breeders have sustained great losses by carrying in-and-in breeding too far, for the purpose of bringing a race to the culmination of perfection.
Settegast, in his paper"On Breeding,” says: “The injurious consequences of in-and-in breeding are not so great and striking amorg cattle and horses as among hogs and sheep, but they must prove pernicious in the end."
II. von Nathusius, in his “Views on Breeding,” (Stockhardt's Agricul.