Home >> Surgery-and-obstetrics >> Affections Of The Ear to Wounds Of Special Regions >> Sterility


STERILITY By sterility is meant the failure on the part of an animal, male or female, to procreate its species; the terms unfruitful, infertile, and barren are also applied to such unprofitable members of the herd, stud, or flock. Sterility is a disease, or rather a symptom of disease, of the reproductive organs which causes continuous, and increasing loss to agriculture. Whilst only the fringe of this complex and highly specialized subject can be touched upon in the space at our disposal, it is hoped to deal somewhat fully with the important question of prevention. At the outset it must be frankly admitted that certain problems still remain unsolved; and the breeding powers of many valuable animals are suffered to fall into dis use largely because sterility has not received the detailed consideration which it deserves. Although breeding lies at the very foundation of agriculture, it is common knowledge that infertility, like contagious abortion, is increasing, especially under intensive systems of manage ment. This deplorable and -constant waste of good breeding material cannot be allowed to continue under conditions which make special efforts to improve British stock-breeding more than ever necessary. Among the many prob lems requiring present attention are emphatic ally those which relate to the pathology of breeding.

Losses. In many herds and studs the exist ence of a certain number of infertile animals has come to be regarded as natural or inevitable. Unless the sterility figure exceeds three to five per cent, few if any precautions are taken, and no treatment is attempted. This general state ment, to which there are commendable excep tions, applies particularly to farm and dairy animals which are often useful for other purposes.

The loss is less real and less apparent when the cow can be fattened for the butcher. But a valuable 1000 or 1200-gallon cow of a deep milking strain is clearly sacrificed if no serious efforts are made to overcome or prevent the disease of the womb and other organs on which sterility as a rule depends. The loss is both immediate and remote. It is excessive in breeds like the Jersey and Ayrshire, whose beef value is small, whilst it is very serious indeed in high priced pedigreed animals of any species which are kept solely for breeding and show purposes. The keep of these barreners, their deterioration, the absence of offspring, and interference with the perpetuation of valuable strains, the serious reduction in the milk supply, the sale of too many individuals, together with the wear and tear of the male, are matters which claim earnest attention. Although the annual wastage is difficult to determine, it is generally conceded that the loss both to individual owners and to the State is enormous. It is probably the case that about 25 per cent of mares and 8 per cent of cows in the United Kingdom are sterile. These figures are merely rough averages founded partly on the writer's personal experience, partly on information furnished by individuals and societies. Needless to say, the figures vary greatly in different parts of the country, more particularly in cattle. Thus 20 per cent of the cows and heifers in abortion-infected districts are not uncommonly attacked. No statistics are available in regard to cows and bitches. Figures relating to horses are practically con fined to thoroughbreds; for, until recently, only thoroughbred breeders were required to make an annual return showing what their brood mares were doing, whether they produced a foal or were barren. Owing to the lack of proper records, most of the Breeding Societies are unaware of the extent to which infertility prevails among the animals in which they are specially interested. There is, however, a brighter side to the picture.

Notwithstanding the existence of contagious abortion, sterility may be largely prevented by proper hygienic measures before, during, and after parturition in all animals. There is no doubt that the problem of control is susceptible of solution in a much larger measure than is ordinarily supposed. The intelligent anticipa tion of the effect of little causes before they become big ones will go a long way to solve the problem of this slowly-developing and insidious disease. Whilst we cannot make every animal productive, experience has shown that the number of temporary and permanent cases of sterility can be reduced very materially. But the help which science can give to Nature must be fully recognized, as shown by the intelligent co-operation of the up-to-date breeder and his expert veterinarian. With closer collaboration between the sciences of veterinary surgery and agriculture, and a thorough application of rational preventive measures, marked develop ments may be expected in the near future. We would not underestimate the difficulties, but these must be overcome by increased knowledge and sheer hard work. There is no doubt that a great demand will be maintained all over the civilized world for highly - bred British stock, particularly horses, cattle, and sheep. That this demand will be met is evidenced by the brisk competition at recent sales, and the deter mination of the patriotic breeder to prepare for future requirements regardless of present cost. Amongst other encouraging signs of the times are: the selection and branding for stud pur poses of imported mares by the army author ities; the system of grants and premiums for small as well as large farm animals; and the annual registration and examination of stallions initiated by the Board of Agriculture.

Need for Investigation.It is a regrettable fact that British breeders, veterinarians, and scien tists have hitherto paid scant attention to sterility, although the subject is of paramount importance and interest both from the economic and scientific standpoints. What is required is a more thorough knowledge of the principles of breeding, the use and abuse of the male, the general management and feeding of both sexes, the structure and functions of the reproductive organs, and, above all, a clear conception of the immense influence of parturition and abortion in the production of infertility. The time is rapidly approaching, we venture to predict, when the progressive agriculturist will no longer permit the accumulation of"drones"in the form of irregular breeders and barreners, and when every effort will be made to stop the constant supply of recruits. The scientific knowledge which is lacking can only be gained by research work along experimental lines. In this connection it may be opportune to mention the decision of the Development Commission some years ago to make a substantial annual grant for research in animal breeding in Scot land. The scheme includes experimental work on farms and in laboratories, particularly in the larger animals, in which sterility is not only most prevalent but most wasteful.

Breeding Records.Within the last decade the excellent practice of keeping records, parti cularly milk records, has come into vogue in many well - managed dairy herds. The pro cedure is adopted at the present time mainly by those dairy-farmers who are in a position to breed their own stock. Apart from these for tunate individuals, the question may be asked:"How many breeders keep a systematic record of the breeding performances of their animals ?"Again:"Is the service card in universal use in the case of pure-bred stock, and, if so, is it duly completed in every detail, and indexed or posted up for future reference ?"It must be admitted that the Stud and Herd Books of the United Kingdom, other than the General Stud Book, give few or no details of the number of females served and the number of living offspring produced, whilst returns of barren mares and cows are conspicuous by their absence. It is surely of great import to be told the number of services performed by a certain sire and the number of resulting full-term pregnancies. Nor are the members of the various breeding societies enlightened in regard to other important matters in which they are, presumably, interested both from a pecuniary and a scientific standpoint.

No doubt these books are framed for a different purpose, but we are glad to note that more information is becoming available with regard to sires. Reverting to the dam: the history of each animal; its behaviour at par turition, with the fate of the afterbirth; the periods and character of cestrum, etc., these and other data would not only assist the breeder in the conduct of his business but they would prove of inestimable value in the elucidation of the sterility problem.

Empirical Methods.The inability of the breeder to perpetuate certain strains owing to the persistent barrenness of some of his best animals, together with the regrettable confusion which exists in the minds of some as to the real cause, is responsible for the employment of the quack, whose colossal ignorance is only equalled by his supreme self - confidence. Generally speaking, a curtain is drawn across his many failures. In cases in which apparent success has attended his blindly - directed efforts, a change of sire, some alteration in the details of management, or time alone may have effected a cure in females which were only temporarily sterile, whilst both"operator"and owner remain in ignorance as to the cause. Further more, the amateur is sometimes the cause of serious injury and infection, complications which may render a simple case incurable. Yet, in spite of the"certain cures,"both medicinal and operative, sterility is steadily increasing in this and other countries.

Structure and Function.The following brief description will, it is hoped, enable the reader who is unfamiliar with the form, position, and uses of the female genital organs to follow our subsequent remarks with more interest and comprehension. There is less need to refer to the simpler genital apparatus of the male. The principal female organs are the ovaries, uterus or womb, vagina, and vulva. The first two are situated in the abdomen and may be readily examined in the mare and cow with the hand in the back bowel, called the rectum, and in the passage called the vagina. The ovaries in the mare are about the size of a duck's egg, some what kidney-shaped, smooth, firm, and notched; they lie under the loins a little behind the kidneys, above the intestines. Each ovary is attached to, and in communication with, the uterus on its own side; but they are rather widely separated. In the cow they are much smaller, rather less than a walnut, and situated close to the entrance of the pelvis. The uterus in all animals is made up of a small main por tion or body, terminating behind in a neck, and dividing in front into two branches called horns; these horns are long and curved, tapering at their anterior extremities where they communi cate with the ovaries. The mare's uterus is shaped like the letter y, being firmly suspended and spread well forward in the abdomen; the cow's womb, on the other hand, curves back wards, bringing the extremities of the horns and the ovaries within easy reach from the vulva. In both animals the neck or cervix is a short thick tube which projects backwards into the vagina in the form of a tap-like projection called the os uteri, or more often the"os."The cervix may be regarded as the mouth of the womb, for it opens at its anterior end into the body of the uterus. The passage which connects the uterus and cervix with the external parts is termed the vagina, which is about ten inches long, and is lodged entirely in the pelvic cavity. The rectum lies above the vagina and the bladder below it. The vagina is succeeded by the vulva, which opens under the tail just below the anus. Proceeding in the opposite direction, the genital canal, as it is called, is formed by the vulva, the vagina, the neck, body, and horns of the uterus, which reach to the ovaries. At one end we have the vulva, at the other the ovaries. The whole canal is lined by a red, velvety, moist and delicate covering called the mucous membrane, which is easily injured by rough handling, strong disinfectants, or as the result of copulation and parturition. The mus cular tissue which forms part of the canal wall is present in greatest amount in the uterus, especially during pregnancy. Here it consti tutes the principal expelling force which gives birth to the foetus. The function or use of the ovary is to mature and discharge the ovum or egg which scientists call the germ cell. The discharge of the ovum is essential to reproduc tion, and it only takes place during the period of cestrum, or rutting. If connection with the male takes place about the same time, the male cell or sperm present in the semen deposited in the genital canal, penetrates and fertilizes the female cell. The fertilized ovum then reaches and becomes attached to the now pregnant uterus, from which it derives its nourishment. The result is the develop ment of the young animal which we call the foetus. Coincidently with these changes, im portant alterations take place in the dam, mainly in the uterus. In nearly every case the cervix remains sealed throughout preg nancy. The words gestation and pregnancy need no explanation; they indicate the period which begins with conception and ends with birth. Estrum or heat is the expression of sexual desire in the female. In the domestic animals it occurs at more or less fixed periods, and is characterized by certain symptoms which are peculiar to each species. It is a well-known fact that impregnation can only occur during °estrum; hence all breeders look for the signs, and endeavour to cover the animal at the right time; if not properly in season, the connection may not take place, or the female may be injured during the service. Two essential phenomena occur at this time in all animals: in the first place, the ripe follicle containing the ovum forms like a blister on the surface of the ovary; it bursts and the ovum is set free ready to meet the male sperm, as already mentioned; the second is the softening and opening up of the cervix to admit the male fertilizing fluid (semen) into the uterus. From this it is evident that conception requires an open, healthy genital canal, containing the necessary active germ cells, male and female. This leads us in natural sequence to a considera tion of the causes of failure on the part of an animal to conceive, which depend upon some departure from .these normal (healthy) condi tions.

Causes. It is now recognized that many of the factors which limit or prevent fertility are merely predisposing or contributory causes, whilst the actual cause is often a definite diseased condition of some part or parts of the genital organs. It is rare to find the male totally and permanently sterile, although he may prove an indifferent stock-getter or actually sterile at times. That the female is much oftener affected than the male is not surprising when we consider the number and nature of the risks to which she is exposed, especially as the result of parturition. The female organs are also more complex than the male, and they are therefore more to disease, the uterus in particular. Sometimes loss of function rather than struc tural change appears to be the cause of the trouble; for example, the semen is thin and weak, or cestrum is absent, irregular, or ex cessive. The uterus may be quite healthy, but the ovary fails to form or discharge the ovum. On the other hand, fertilization of a healthy ovum is of no avail if the ovum cannot obtain a firm attachment to the uterus on account of disease. A cure cannot be claimed if successful efforts to impregnate an animal are followed by early abortion. But it is common knowledge that abortion frequently leads to sterility; indeed the two conditions are so intimately asso ciated that they have been described as different phases of the same disease.

What may be termed mismanagement is re sponsible for a certain number of infertile animals; this includes errors in diet, work, or exercise; over-use; withholding the bull; and, possibly, in-breeding. Many foods are blamed for causing sterility, but the evidence is by no means convincing. Generally speaking, nitro genous foods like peas and beans increase vigour and therefore sexual desire; whilst grains, maize, and similar materials are less active in this respect. The fact is that the constituents of a rational diet are of minor importance, provided the diet is suited to the circumstances of the particular case. At the same time stimulating artificial foods are best avoided for breeding animals. It should be remembered that the presence of pronounced cestrum is no guide as to the female's ability to breed, nor is the power to copulate any criterion of sexual soundness in the male. After all, it is the amount of food, rather than the actual constituents of the diet, which is the important point. This depends upon the age, the amount of work, and the number of services on the part of the male. Thus, a stallion serving, say, eighty mares, or a bull a hundred cows, requires a generous diet rich in proteids; but the ration needs to be considerably reduced during the off season. Most harm is undoubtedly done by over-feeding. This is a common practice in animals intended for shows and for the sale yard. The intensive system of management, to which pure-bred stock in particular are subjected, is probably responsible for most of the sterile young bulls and heifers. At the same time the extent to which high-feeding per se is responsible is not always clear, for it is frequently accompanied by insufficient exercise. If, in addition, the cow has a long milk ancestry, several factors combine to weaken the genital organs and to make them sluggish. In some instances, how ever, the laying-on of fat appears to be the result, not the cause, of the sterility; the in fertile animal may exhibit a tendency to fatten. With regard to exercise, there is a general con sensus of opinion that confinement, like over feeding, lessens fertility, and that bulls, no less than mares and stallions, should receive regular work in order to preserve their breeding powers. Bulls in confinement become increasingly lazy and heavy after four years old, and their fer tility rapidly diminishes. Plenty of freedom is always advisable for the smaller animals. The opposite conditions, poverty and overwork, are relatively unimportant, except perhaps in young males. A mare in poor condition usually con ceives, but systematic overwork may cause her to slip her foal. If the foal is carried to full term it suffers from insufficient milk. Our next point, excessive sexual use, has reference only to the sire. Not infrequently, when par turition is required to take place at a certain season, the powers of a male are overtaxed by too frequent use during a comparatively limited period. Abuse of this kind is commonest among young bulls when first put to stud, especially when they are allowed to get down in condition. The result is not difficult to foresee; the semen becomes watery and less potent, the male sperms sluggish and few in number, and the act of copulation is indifferently performed and in creasingly unsuccessful. If neglected, the young bull becomes unable to copulate. Incidentally his heifers and cows come in season again at regular intervals, and the whole time-table and internal economy of the herd are disarranged. Again, some stallions are allowed too many mares at the beginning of the season before they are properly conditioned for stud purposes by a rational system of management. The prepara tion of the stallion by means of regular work and moderate judicious feeding will materially increase the number of foals, provided he is allowed only a few mares during the first few weeks. Later on, during the heavy part of the season, all authorities are agreed as to the neces sity of generous feeding and the maintenance of good condition for the proper performance of the work. Practically all breeders limit their stallions to a certain number of mares according to age and other considerations; but it is highly important that the animal should be in good hard condition at the beginning of the season, not too fat and soft. Age is seldom an obstacle to conception. Whilst it is true that the semen of very young males is of low fertilizing power, yet a young sire of breeding age is always more prolific than an old animal, provided he has been properly fed (not overfed) and cared for. Again, many brood mares continue to produce foals with more or less regularity to a good old age. Yet every one knows the difficulty which is experienced in impregnating a mare covered for the first time late in life. Those which have been in work for a number of years require a long run at grass. It must be admitted, how ever, that as age advances there is a tendency to senile decay of the essential organs of repro duction, the ovaries and testicles, which of course reduces or abolishes fertility. We believe that heavy fat males, and females which have not been regularly bred, suffer most in this respect. Without discussing the merits and demerits of early breeding, it is a matter of common ex perience that mating at a reasonably early age tends to insure regularity in breeding and a proper activity of the mammary glands. With regard to lactation, experts are agreed that when a mare served late in life becomes pregnant, she is frequently short of milk when she foals. At this stage we would direct attention to the prac tice of withholding the bull which prevails, in normal times, in some large dairy herds. The object is, naturally, to prevent cows calving down during the off season when there is less demand for milk. The London market may be cited as an example. By systematically pre venting animals from breeding, sterility, at least of a temporary nature, may easily be induced. We have repeatedly observed difficulty in getting cows in calf which have been subjected to this unnatural interference. Another contri butory cause of comparatively slight importance is This acts by reducing vigour and therefore the fertility of the domestic animals. Highly-bred and in-bred males are considered by some to be less potent, but a great deal depends upon their rational handling. Lastly, climatic and nervous influences call for some mention. They include extremes of heat and cold, changes in the environment, and excitability. Spring is, of course, the natural or ideal time for concep tion to take place. Thus cows which cannot be got in calf whilst tied up during the winter frequently become pregnant when turned out with the bull in the early summer. Mares are most prone to suffer from undue excitement; they appear to be very sensitive in the vagina, which may be in a state of spasm. The mare strains violently after the service and ejects the semen. This pronounced irritability is not due, as a rule, to any injury or disease of the passage or hind parts. Rather is it a matter of tem perament. A good gallop or a long spell at the plough will frequently settle a nervous mare and enable her to conceive. In this connection it is interesting to note that the Arabs often gallop such mares to a standstill, and then put the horse over them. Ejection of the semen may be prevented by pouring or dashing cold water over the loins, walking the mare about in order to distract her attention, or by the appli cation of the twitch. In some cases it may be necessary to administer a dose of sedative medicine shortly before copulation.

The actual cause of sterility usually has its seat in the genital organs themselves, which are affected with some disease. Abnormalities are rare. The young animal is born fully developed and potentially productive in nearly every instance. Needless to say, when certain parts are defective or absent at birth, sterility is the invariable result. These anomalous conditions occur in rig colts with abdominal testicles, in hermaphrodites with genital organs of both sexes, in hybrids like mules, and in the case of some twins. It is generally recognized that the female of twin calves, the so-called free-martin, is nearly always infertile. Another peculiar abnormality, familiar to shorthorn breeders, which interferes with or prevents copulation, is observed in"White Heifer Disease"due to the persistence of the hymen or adhesion of the walls of the vagina. Unlike most congenital defects, it is amenable to treatment by opening up the closed passage and preventing reunion during the healing process. Of more importance are those diseases which can be brought more or less under control, and which are very prevalent in barren animals. We refer particularly to chronic inflammations of the uterus and cervix, and cysts in the ovaries. These inflammations frequently follow abortion, and, to a less extent, ordinary parturition, owing to the fact that infection of the uterus readily takes place at such times. In many herds the number of cases of abortion bears a close relation to the number of sterile cows and heifers. By infection we mean the invasion of micro-organisms, which occurs, apart altogether from abortion, when the genital passages are injured during the birth of the fcetus. Retention of the afterbirth is also a prolific cause of infection, and therefore of sterility. In mares abortion is a less common cause of sterility, although many mares, like cows, abort either at grass or at work before the twelfth week. This early"invisible"abortion is seldom observed. The mare is tried regularly with the horse until she suddenly comes in season. Unless this occurs too late in the year, she usually becomes pregnant a second time, and carries her foal to full term. Cows, on the other hand, usually go aver to the bull several times after abortion at all stages of pregnancy. It is a well-known fact that mares seldom slip their foals a second time in succession. But sometimes the fertilized ovum or embryo is not expelled at once. It dies in the uterus and is retained there for a time, being eventually got rid of as a more or less destroyed mass. When this happens, the uterus may be converted into an abscess. The cause of such early abortions must be sought for in disease of the mucous lining of the uterus, which prevents the proper nourishment of the ovum, and its intimate attachment, which ought to take place during the second month of pregnancy. Before pro ceeding further, attention should be directed to the close relation which exists between the genital organs, whereby inflammatory processes beginning in the cervix or uterus frequently spread to the ovaries or vagina, or both. The ovaries may be first affected, in which case the disease generally extends to the uterus. Hence, in examining mares and cows which have been barren for some time, the veterinary surgeon may find signs of disease in several organs, each of which requires different handling. The owner will realize that these complications in evitably delay, and sometimes prevent, recovery. Taken in the early stage, however, the affection is, generally speaking, simple and uncomplicated, and admits of a fairly rapid cure. The fact that the cervix is more frequently affected in mares accounts for the success which attends the indis criminate practice of"opening the womb"and the operation known as artificial insemination. Disease of the neck or cervix may arise from injuries in copulation, or rough handling by amateurs; but many cases are due to laceration and bruising during difficult or precipitate labour. It is therefore not surprising that

maidens are seldom affected.

Physical inability to copulate may be observed in either sex, more especially in the male, from adhesions, tumours, inability to erect or intro duce the penis, or disparity in size. In the latter instance the female is too small or too large for the male. Sometimes the male animal is able to mount and introduce the penis, but he is powerless to complete the act. This occurs in stallions which suffer from excessive erection, and it is curious to watch their be haviour with mares in use; the large penis may or may not be able to enter the vagina; if so, no semen is discharged, and hence there is an absence of the characteristic wave-like movement on the under surface of the penis and the organ is withdrawn still erect. These symptoms should be carefully observed, for they always mean that the male is useless.

Sterility is thus due to many causes, some of which cannot be enumerated here. Briefly, it arises from functional derangement or organic defects, the result of mismanagement or disease. We might add that the cause may be readily apparent, or it may require several examina tions by an expert. In exceptional cases it may elude the most careful search.

Symptoms. The fact that the animal fails to breed may be sufficient, or more than sufficient, for some owners. But close observation of its behaviour is necessary for the accurate diagnosis and cure of the disease. The most prominent symptom in the female in all domestic animals is the occurrence of abnormal cestrum—that is to say, the heat is too frequent, excessive, too short or weak, or altogether absent. It is evident that we have three different things to consider, viz. the periods, the degree or intensity, and the duration of the cestrum, any or all of which may be at fault. In the first place, the animal comes in season too frequently or at too long intervals. Here the period is at fault. Whilst the normal period naturally varies in each species, in the healthy cow and heifer, for example, cestrum occurs every three weeks, or twenty to twenty-two days. Most cows take the bull six to eight weeks after calving; some may even come in heat in four to six weeks; on the other hand, the signs of cestrum are generally delayed for several months in deep milkers, and to a less extent in those cows which are suckling their calves. In the second place, the degree of heat varies greatly; in some it is very excessive, constituting what is called nymphomania. This condition, which may be slight or very marked, is characterized by frequent or constant general and sexual excitement; there is loss of condition and diminished milk secretion; affected animals cease to thrive, become irritable and restless, whilst they tend to mount and annoy others, and even become positively vicious. Mares frequently kick; they are very ticklish and squeal, as a rule, when touched, and they often pass urine in small quantities. As regards age, nymphomania is mostly observed in mares past middle age, in cows between the fourth and the seventh calf, and in bitches which have been bred several times. The symptom is uncommon in sheep, goats, and pigs, whilst heifers are rarely affected. The nymphomaniac cow is generally called a buller. This is a useful term, for it gives a good idea as to the animal's condi tion. In most cases cysts are present in the ovaries; they are the chief cause of \ the ex aggerated cestrum, although the latter symptom may be absent. The cysts interfere with the formation of healthy ova with resulting sterility. But nymphomania is also produced by chronic inflammations of the uterus and cervix; indeed, one frequently finds the whole genital canal from the ovaries to the vulva more or less affected. Thirdly, the duration of the cestrum is brief or prolonged. If too short and weak, it may be unobserved, especially during the night; sometimes it is prolonged for several days. The average duration in a healthy cow is about sixteen to twenty-four hours. In animals which are closely confined for long periods cestrum is often weak, although the periods and duration are quite normal. No disease may exist in such cases, which are quite common in dairy cows. The cows may not even go out to water for six months, and cestrum may be so slight in some of them that it passes off unnoticed, except by a very careful cowman. The presence of a blood-stained discharge from the vulva shows that heat has just taken place; but it is too late to offer thd bull. A little blood is commonly seen in cows on the second day after the onset of cestrum, provided con ception has not occurred. It is therefore a bad sign for the breeder after service with the bull.

Lastly, cestrum may be quite absent, and the cow or heifer is known as a dumb buller. Naturally, if connection has taken place before cestrum ceased to make its appearance, the animal may be thought to be pregnant. Here, again, the ovaries and uterus may be diseased, as in the opposite condition, nymphomania; but on inserting the hand into the rectum and feeling the ovaries we have frequently found a fleshy growth, the removal of which has been followed by cestrum and conception. Before leaving the important subject of cestrum, we would point out that the above symptoms are usually, but not always, associated with sterility. But it seems a confusion of cause and effect to attribute the sterility to the abnormal cestrum. Animals so affected are sterile, not because they exhibit abnormal cestrum but because of physical changes in the genital organs arising from disease of these parts. The altered char acter of the heat is a symptom of this disease. Again, some infertile subjects come regularly in season and take the male; but such cases are exceptional, and careful observation will often detect some alteration, however slight, in the duration or intensity of the cestrum, with, possibly, some of the following local symptoms. From what has been said, it is plain that the characters of the cestrum constitute a valuable indication of the animal's soundness from a breeding point of view. These characters should, we venture to say, be entered in the herd or stud book for future guidance.

Local Symptoms. In the cow a valuable and fairly constant symptom is relaxation and sinking of the ligaments on one or both sides of the pelvis. This causes the muscles to fall in, and the hip or quarter becomes distinctly flattened. The most marked alteration occurs on each side of the root of the tail; in this situation the firm, tense, cord-like ligament disappears and there is formed a pronounced hollow in which the wrist or arm may be placed. The softening and sinking of this ligament certainly occurs to a slight extent during healthy °estrum, and to a much greater degree in cows preparing to calve. Indeed, all breeders recognize this sign of approaching parturition to which the expression"the bones are down"is often applied. But in healthy cows about to calve the sinking is temporary and equal on both sides, whereas in disease it is permanent, excessive, unequal, or confined to one side. As a rule the hollows point to some disease of the genital organs, especially of the ovaries. Again, a slight slimy discharge may issue from the vulva, adhering to the long hairs and soiling the tail and hind parts. When the uterus is affected, this discharge is more abundant and mixed with dirty, creamy or thin watery pus; the vagina, too, is generally relaxed and widely dilated, and the cervix is wide open instead of being closed, or nearly so, between the periods of °estrum. These four symptoms, viz. the hollows at side of tail, the open vagina and cervix, and the slimy discharge, are often present in nymphomania, as well as in dumb cestrum. Contraction or closure of the cervix is also met with in all animals. That portion of the cervix which projects backwards into the vagina, called the"os,"is very often the seat of disease in mares; it becomes thickened, hard, often ulcerated, bleeds readily, and the opening is displaced downwards and to one side. In addition, the cervical canal—in other words, the passage through the neck of the womb— is twisted, requiring care and patience in intro ducing the finger. The closure of the cervix prevents the semen of the stallion entering the uterus. Lastly, the inflammatory changes already referred to, which are commonly found in the uterus and ovaries of sterile animals, require the expert, with his hand in the rectum, for their detection. These affections of the uterus are often mild in the early stages; they commence some days after parturition or abor tion, and, seeing that they may produce com paratively little disturbance of the general health for some time, their existence may not be suspected by the attendant. Nevertheless there is more or less straining for a few days, and a purulent discharge which may gradually subside, only to reappear at the first cestrum. The appetite may suffer, whilst the milk yield is always below par. It is well recognized that a cow does not come to her full milk so long as a discharge is present. If the owner wisely calls in his veterinary surgeon at this early stage the latter soon discovers that the uterus is thickened, swollen, and longer than normal; and already, in some cases, the ovaries have become cystic, large blebs or blisters being dis tinctly felt on the surface or in their substance. (Estrum soon becomes irregular, or fails to make its appearance; the cervix is closed, and the discharge collects in the uterus to an inordinate extent. If connection has previously taken place, pregnancy may be presumed, but this assumption is easily dispelled by means of an internal examination. It is certainly possible for pregnancy to occur in slight cases of uterine trouble (uterine catarrh); but, for reasons already stated, abortion is liable to follow in a few weeks. Many cows suffering from the disease under consideration (chronic metritis) steadily lose condition, become unthrifty, and give little milk unless rational and timely measures are adopted.

Diagnosis. In dealing with the problem of sterility in all the domestic animals, the most important thing of all is early and accurate diagnosis. It is clear that we must treat the right spot, know what is worth treating, and get the case early in order to effect a speedy cure before complications have set in. Although prevention should be the chief aim of all con cerned, few endeavours have been made to check the disease at its source. One reason for this unfortunate policy of laisser-faire is the ignorance which still exists in the public mind as to the actual starting-point. Let us take a typical case in a cow which has been"over"repeatedly to the bull and shows no signs of holding; she may have aborted or had a difficult calving; in either case she probably retained her cleansing (afterbirth) and suffered from a discharge, with slight straining occasion ally, for some weeks. The fact that the uterus was diseased was, however, not recognized owing to the insidious nature of the trouble.

The infection, which is invariably present in such cases, was allowed to take its course, until extensive and often incurable changes have taken place, not only in the uterus, but also in the ovaries and other parts. The result is much loss of time and waste of money in main tenance for want of simple hygienic precautions during and after calving. It is true that slight infections sometimes recover spontaneously; but the disease, if unchecked, is generally pro gressive and leads to permanent loss of breeding power. In other words, most cases are simple in their inception; by and by they become difficult or impossible to treat, or not worth treating.

One of the most important duties of the veterinarian is the detection of pregnancy in its early stages. This is necessary in order to avoid mistakes, and also to allow treatment to be begun without delay. Disease of the uterus may be mistaken for early pregnancy, or vice versa. Most breeders can recall with sorrow valuable dams which were sold or killed as barren, and which proved to be pregnant.

We have always advised, and carried out, the examination of every animal in the herd. This is all the more necessary when abortion or sterility has prevailed to any extent, in order to concentrate one's efforts on the best animals which have not been too long affected. In the cow and mare pregnancy can be detected with reasonable accuracy as early as the sixth to the tenth week; in heifers carrying their first calf, between the fourth and sixth week. A second or third examination may be required at this early date if the uterus is not quite normal, and when no proper record has been kept. The latter will greatly assist the expert in coming to a decision, not only in regard to pregnancy, but in the whole procedure which he decides to adopt in the owner's best interests.

In small animals like the bitch, in which a full internal examination cannot be made, the puppies may be felt through the abdominal wall towards mid-term. The following summary of points to be noted in the veterinary examina tion of breeding animals for sexual soundness may be of some interest: (a) Female 1. General character of cestrum.

4. Appearance of external genitals, vulva and vagina.

5. Internal examination, both rectal and vaginal. To obtain reliable information, make at least two, one between and one during cestrum.

6. Complete breeding record.

7. Reaction of vaginal mucus, tested with litmus-paper.

8. Observe act of copulation and subsequent behaviour.

N. B. Pay special attention to the state of the"os"(cervix), which should be open and soft during cestrum, firm and closed to a great extent at other times.

(b) Male 1. External examination of drawn-out penis; also scrotum (purse), testicles and other parts.

2. Pass catheter, if required.

3. Internal examination through the rectum.

4. If able to copulate, closely observe the act, and note if semen is ejaculated.

5. Collect semen from vagina immediately after connection, and examine with the micro scope.

Prevention and Treatment.This resolves itself, so far as prevention is concerned, into a thorough understanding and avoidance of the causes which we have mentioned. In the actual handling of barren animals, however, effects rather than causes have to be dealt with. The measures which are adopted for cattle are also applicable, with certain modifications, for mares and the smaller species. Reference has been made to the fact that sterilityis largely dependent on the accidents and diseases connected with parturition. We would add that when a cow aborts, has a difficult calving, suffers from a vaginal discharge, or holds her cleansing, the veterinarian should be consulted early in order that he may combat the infection and prevent the diseases which give rise to infertility. The significance of checking the sterility disease at its source has not been sufficiently realized. At a later stage, when the mischief has been done, an external and internal examination will enable the practitioner, assisted by the breeding record, to determine the nature and extent of the disease, and, further, whether a cure is probable within a reasonable time; if incurable, the cow will of course be prepared for the butcher and slaughtered when the milk yield ceases to be profitable. Only those cows and heifers which are worthy of retention in the herd will be placed under treatment. At parturition, the chief thing to remember is to avoid infection, which is very apt to occur from even slight wounds inflicted during birth; from dirty hands and instruments, ropes, syringes, etc.; from dirty surroundings, and from retention of the after birth. The latter is very common, even more so after abortion than full-term birth, and although it cannot be prevented, its evil effects may be counteracted to a great extent by thorough and frequent cleansing and dis infection of the uterus. The early and com plete removal of the afterbirth is always desir able, but not always attainable, and the owner would do well to leave the matter to the discre tion of his professional adviser. The hygienic precautions which should be observed will be familiar to every farmer and breeder who has been troubled with abortion, joint-ill, and similar diseases. The animal's surroundings should be clean before calving, but during and after birth the floor and box should be repeatedly cleansed and disinfected, fresh straw laid down, and the hind parts, including the vulva, washed frequently with a mild disinfectant solution. Vaginal and uterine injections are of the greatest importance in difficult births, twins, or in cows and heifers which hold the cleansing; but we would point out that it is not safe to allow a cowman or attendant, however careful he may be, to interfere with the uterus. Apart from rupture, which may easily occur, unskilled hands often do more harm than good. We recall several valuable cows and heifers which were killed or ruined in this way, and hence we may be permitted to utter a word of warning. The vagina, however, may and should be gently syringed two or three times a day with an ordinary quart brass enema pump, to which a fairly stiff rubber tube is made to plug on, not screw on. As an alternative, the ordinary wooden nozzle may be covered with rubber tubing, which is allowed to project a little in front of the nozzle. Any of the following solutions may be employed at blood heat: (1) I. per cent of cresol solution (Liquor Cresolis Co. B.P.) or Jeyes' fluid, three tablespoon fuls to a gallon of water; (2) permanganate of potash, or Condy's fluid, 1: 1000. The fluid is added to the water until it is a nice claret colour; (3) perchloride of mercury, 1: 8000 10,000. For bulls and rams, in which the opening of the sheath is very narrow, a metal tube may be attached to an extra-long ball rubber syringe. In addition, the long hairs in front of the sheath should be cut short. The above solutions may be made a little stronger for washing the external parts; but if the strength recommended is exceeded for syringing the vagina and sheath, irritation and severe straining may be set up, especially in young animals. In the case of very sensitive heifers, and where there is much inflammation in any animal, it may be wise to stop the injections, and to use capsules instead. One more remark about vaginal injections may be opportune. It should not be supposed that douching the vagina will suffice to control or prevent infection of the uterus. Employed alone, their value is very limited. They must be supplemented by irriga tion of the uterus itself.

The above treatment should be continued twice daily, later on, once a day, until the dis charge has ceased for several days—generally about the If a little fresh discharge makes its appearance at the first cestrum after parturition, several more injections should be given. Under no circumstances should copula tion be permitted until cestrum is quite normal, and the genital organs are in a healthy condi tion. Just before connection takes place it is well to douche the vagina with a warm solution of bicarbonate of soda in the pro portion of one or two teaspoonfuls, to an imperial quart of water.

Passing to a consideration of the sterile mare and cow, the causes are as numerous and varied as the short cuts to cure, hence no routine line of treatment can be laid down. Each case must be dealt with on its merits by the veterinary practitioner with the full co-operation of the owner and attendants.

As a rule, what may be termed a"combined treatment"is necessary; briefly, this consists in crushing cysts in the ovaries, massaging and cleansing the uterus, opening up the cervix, and performing artificial insemination. One or several of these and other surgical procedures may be indicated, and the operations may require to be repeated. Drugs can often be dispensed with, although tonics and sedatives may be useful in certain cases. Those drugs which excite sexual desire are frequently administered by amateurs, but, as a rule, they have no effect in assisting the formation of healthy sperm and ova. Sometimes, we admit, when the genital organs have been merely sluggish, cestrum being weak or even absent, successful copulation has followed their use. More often, they only succeed in causing irrita tion, aggravating the disease, and in setting up a kind of false cestrum without increasing fertility. Drugs of this nature are capable of great abuse; they should only be administered by professional advice to animals in which no disease can be discovered after several careful internal examinations. Rather would we recommend strict attention to exercise, work, and feeding, with frequent consort with the male when disease is absent. Backward maiden mares should be frequently teased by the stallion, the cervix examined, and the uterus massaged by means of the hand in the rectum. These manipulations seldom fail when the disorder is merely functional, un accompanied by any structural change. We have referred to the beneficial effects of work in such cases. Fat sluggish mares are often put to hard work until cestrum appears, and served immediately they are unyoked. Pedigreed cows, which are too fat and therefore indifferent breeders, tend to become vigorous and fertile at the plough. Such work is, however, usually restricted to bulls. In some obscure cases of sterility, in different species, we have known a change of environment produce good results.

It is also a fact that a change of stallion, especi ally a stallion of another breed, sometimes proves effective.

Nymphomania is variously dealt with accord ing to the case. The"combined treatment" at which we have hinted will probably be successful in the earlier stages, with attention to diet and work. Sedative medicines afford only temporary relief, but they may be very useful in controlling the irritation whilst surgical treatment is in progress. The operation for removal of the ovaries, known as ovariotomy, may be necessary. It may be performed in cows, bitches, and other animals, but mares are more often spayed for this reason, with suc cessful results, if the mare is not too old and too long affected. But we must remember that the ovaries may be diseased without the mani festation of vice and excessive sexual desire. When only one ovary is affected, with or without nymphomania, its removal may enable the mare to breed. This partial operation is always worth a trial in valuable breeding stock, large or small.

Inability to copulate may also require surgical interference: for example, the removal of tumours, and the breaking down of adhesions, in both male and female external organs. Con traction or complete closure of the cervix is popularly supposed to be a common cause of sterility, hence rough attempts are often made to dilate a perfectly healthy organ ! Disease of this part can only be properly handled by a surgeon, and the operation may require a good deal of time and patience.

Artificial insemination is a very popular operative procedure for barren mares. It is less necessary, but occasionally beneficial, in other animals such as bitches. Females sired by very small or very large males, of their own or a different species, are also sometimes in seminated. The operation consists in introduc ing the semen of the male, after connection, into the uterus of the same or another mare by means of a special syringe. It may be practised when any obstruction exists to the natural passage of the semen into the uterus. This obstruction may be present in the cervix, vagina, or vulva, most frequently, as we have seen, in the cervix. Conditions which prevent copulation, or which destroy the male sperm, are also overcome in this way. Another advantage is that artificial insemination conserves the powers of the male, Given several mares in season at one time, the semen from one service can be utilized to impregnate them all, provided certain precau tions are observed. It is obvious that in cases where the trouble is situated further forward, viz., in the ovary or uterus, the operation can serve no useful purpose, and attempts to in seminate such animals only tend to cast discredit both on the operation and the operator. In properly selected cases, experience has shown that 90 per cent of inseminated mares conceive when the method is properly carried out. Lastly, we would deprecate the common prac tice of"trying"barren mares and other animals at frequent intervals when the sterility is due to some of the organic changes mentioned above. Sexual excitement in such cases merely delays recovery; and connection should not be allowed to take place until the disease from which they are suffering has been cured.

Conclusion.Although most of the remarks in this paper refer to the mare and cow, we might add that they apply also, with certain modifica tions, to sheep, pigs, and dogs. The handling of sterile animals, especially the larger species, is trying and exacting work; but the results obtained are well worth the pains taken, provided the owner realizes the difficulties which have to be overcome. The writer hopes that he has been able to explain some of these difficulties, and thereby enable the intelligent breeder to avoid them or to tackle them promptly at an early stage when they are much more easily dealt with. But it should be recognized that opera tive treatment cannot be expected to produce immediate results, at any rate in old-standing cases. Sterility is essentially a chronic disease, and it is well to remember that there is no specific for its cure. Treatment must depend on the practitioner's detection of the cause; and the breeder can render great assistance by supplying full particulars of his animals, and by encouraging his men to carry out the minor details of the treatment to the letter. What is wanted is constant care, attention to detail, and patience.

animals, uterus, disease, mares and cestrum