PARALYSIS OF THE HIND PARTS.
In ill-fed, weak, unthrifty cows palsy of the hind limbs and tail may appear in the last weeks of pregnancy. The anus and rectum may participate in the palsy so far as to prevent defecation, and the rectum is more or less completely impacted. Exposure to wet and cold are often accessory causes, though the low condition, general weakness, and the pressure on the nerves going to the hind limbs are not to be forgotten. Something may be done for these cases by a warm, dry bed, an abundant diet fed warm, frictions with straw wisps or with a liniment of equal parts of oil of turpentine and sweet oil on the loins, croup, and limbs, by the daily use of ginger and gentian, by the cautious administration of strychnia (1 grain twice daily), and by sending a current of electricity daily from the loins through the various groups of muscles in the hind limbs. The case becomes increasingly hopeful after calving, though some days may still elapse before the animal can support herself upon her limbs.
EXTRAUTERINE GESTATION (FETUS DEVELOPING OUTSIDE THE WOMB).
These curious cases are rare and are usually divided into three types: (1) That in which the fetus is formed in or on the ovary (ovarian gestation); (2) that in which it is lodged in the Fallopian tube, or canal between the ovary and womb (tubal gestation); and (3) that in which it is lodged in the abdominal cavity and attached to one or more of its contents from which it draws its nourishment (abdominal gestation). Undoubted cases of the first and last varieties are recorded as occurring in the cow. The explanation of such cases is to be found in the fact that the actively moving sperm cells (spermatozoa) thrown into the womb have made their way through the Fallopian tubes to the ovary. If they met and impregnated an ovum in the tube, and if the consequent growth of that ovum prevented its descent and caused its imprisonment within the tube, it developed there, getting attached to and drawing nourishment from the mucous walls. Such product has its development arrested by compression by the undilatable tube, or, bursting through the walls of the tube, it escapes into the abdomen and perishes. If, on the contrary, the spermatozoa only meet and impregnate the ovum on or in the ovary, the development may take place in the substance of the ovary, from which the fetus draws its nourishment, or the impregnated ovum, escaping between the ovary and the open end of the tube, falls into the abdominal cavity and becomes adherent to and draws nourishment from some of the abdominal organs (womb, bowel, liver, stomach, etc.).
Symptoms.—The symptoms are those of pregnancy, which may be suddenly complicated by inflammation (peritonitis), owing to rupture of the sac containing the fetus; or at full term signs of calving appear, but no progress is made; an examination with the oiled hand in the vagina or rectum finds the womb empty and its mouth closed. Further examination will disclose the fetal sac attached in some part of the abdominal cavity and containing the more or less perfectly developed body of a calf. In the most hopeful cases the fetus perishes at an early stage of gestation, becomes inclosed in a fibrous sac, and is slowly absorbed, its soft parts becoming liquefied and removed and the bones remaining encysted. In some cases the bones have finally sloughed into the rectum or through an artificial opening in the side of the belly.
Treatment.—Little can be done in such cases except to quiet pain and excitement by anodynes (opium, chloral, etc.) and leave the rest to nature. A fistula discharging bones may be dilated and the bones extracted, the sac being then washed out with a solution of 10 grains bichlorid of mercury in a quart of water. In certain cases with a live calf a skillful operator may be justified in cutting into the abdomen and extracting the calf with its membranes, using the lotion just named as an antiseptic.
PROLONGED RETENTION OF THE FETUS.
Even when the fetus has developed within the womb it may fail to be delivered at the proper time; labor pains have quickly subsided and the cow resumed her usual health. In such cases the calf dies, and its soft parts are gradually liquefied and absorbed, while its bones remain for years in the womb inclosed in the remains of the fetal membranes. These may be expelled at any time through the natural channels, or they may remain indefinitely in the womb, not interfering with the general health, but preventing conception.
If the true condition of things is recognized at the time of the subsidence of the labor pains, the mouth of the womb may be dilated by the fingers, by the insertion of sponge tents, or by a mechanical dilator ([Pl. XX], fig. 6), the fetal membranes may be ruptured and the calf extracted. After the removal of the calf and its membranes the danger of putrid poisoning may be obviated by injecting the antiseptic solution advised in the paragraph above.