MALFORMATIONS AND MONSTROSITIES.

Otago Witness, Issue 2087, 22 February 1894, Page 8

MALFORMATIONS AND MONSTROSITIES.

We (North British Agriculturist) have several inquiries as to the nature and causes of such conditions. They depend upon impaired, arrested, or abnormal development of the ova or embryo. But in many cases it is difficult to discover their determining causes. The mother may not, so far as is known, have been subjected to accident, fright, or rough treatment. In other cases the monstrosity is reasonably ascribed to the pregnant animal having had a serious fall, having been struggling in an awkward position, or having a bad fright, Inlamb ewes that have been terrorised by stray dogs not infrequently produce imperfect or deformed lambs, and are likewise apt to lamb prematurely. Some monstrosities, it is believed, depend upon a faulty state of the male semen or of tho female ova anterior to or at the time of impregnation. Deformed chicks can be artificially produced from sound eggs which have been sharply shaken, kept during incubation in an upright position, perforated so as to cause admission of a little air, or the shell in part covered with varnish. But uniform results are not always produced by any of these methods. The same injury to the egg does not always produce the same abnormal effects. Various congenital deformities are met with in the domestic animals, but whether they are more common than in the ferine Btate is not known. Alike in human and other species, the cranial and palatine sutures sometimes close hardily and imperfectly. Occasionally this condition is greatly aggravated ; the formation of the bones of the skull and face is early arrested, and the brain, not subjected to pressure, is unusually large and soft. Cavitieß of the thorax or abdomer, tho latter more frequently, may be open, and their viscera, usually of great bulk, float free in the uterus. In an early stage of evolution, the growth of one or more organs is liable to be checked. The whole of one or more limbs, or portions of such limbs, may be absent, shrunk, or deformed. The body is sometimes twisted, usually either laterally, or the fore or hind limbs are drawn .close together, the four limbs of the roached hunchback being found in the passages. Twin monstrosities occur in which the duplicated parts are more or less perfect. These were formerly ascribed to two ova coalescing, but are now believed to result from duplication of parts during the earlier stages of development. It is in thjs way that extra limbs, digets, and other parts are formed. But what forces determine such duplication is not explained. Many ef these monstrosities obviously cause much trouble and risk in parturition.