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Few people are aware of the great extent to which fowls are infested with
are rarely seen, because they are seldom voided,
No doubt, therefore, a slight ventilation of
When a fowl's entrails are drawn and laid out they present somewhat the appearance shown in the illustration, Fig 1. The crop is shown at a, the gizzard at b, the duodenum at C, the small intestine at dd, the two cæca at e e, and the cloaca at f. The small intestine is partially held together by a thin transparent membrane, the mesentery, also shown in the illustration.
Strange as it may seem, this small tube er. tending from mouth to vent, from a to f, is subject to the attacks of more than a dozen different parasites, all more or less injurious.
It is sometimes said that these parasites do no harm, but this is a fallacy. The truth is
that in moderate numbers parasites oftimes do Fig. 1.-Intestinal canal of the
not inconvenience their host very much. Only
when their numbers rise much above the average b, gizzard. c, duodenum.
quantity found among animals in a state of
nature do the parasites cause serious injury. s, cloaca.
Any reasoning person will at once see, however,
that domesticated animals, on account of the nature of their confinement, are much more liable to parasites than wild
common fowl. a, crop.
animals, and fowls are subject to this rule. A fowl scarcely ever acquires parasites except from another fowl, directly or indirectly. Hence, the closer the confinement the more chance there is of infection. This accounts for the great abundance of worms in fowls in confined town runs.
Turning now to figure 1, it is to be noted that all parts of the intestine are subject to the attacks of worms, and it is a remarkable fact that each part
has its own particular
more particularly in the Fig. 3.-Female Heterakis inflexa, Fig. 2.-Female Heterakis infiexa, small intestine, small
c, vulva. natural size.
round worms more par
ticularly in the cæca. In this article attention will be confined to the two round-worms most commonly found in the small intestine and the cæca.
The appearance of the larger of these worms is well shown in figures 2, 3, and 4. Figure 2 shows a female worm, natural size. Figure 3 shows another female with more particularity, also natural size. Figure 4 shows a a male worm, natural size. It will be noted that the males are somewhat smaller than their mates, and also slightly different in appearance. The natural habitat of these large worms is the small intestine of the fowl, the part lettered d d in figure 1, and they do not occur elsewhere in the bird. Sometimes younger specimens of a smaller size will be found among these full-grown worms; but these are rather rare—so rare indeed that thus far no sharp-eyed naturalist has secured drawings of them.
The adult worms are round, somewhat shiny and transparent. They move slowly, or hardly at all, which fact seems to have secured them the name inflexible, the technical name being Heterakis inflexa. These worms appear to live mostly upon the contents of the fowl's intestines, and to do no harm by biting and sucking blood, as do some other species. They are therefore of small annoyance to the fowl, so long as their numbers are few. When, however, their numbers are great they cause a stoppage of the bowels, and serious consequences are sure to follow.
The greatest loss is to be feared when these worms find their way into young chickens. Chickens are much more delicate than older fowls, and suffer more accordingly. Many of the young Fig. 4. - Male Heterakis ingera, chickens that die so mysteriously are killed by worms.
The anatomy of the Heterakis inflexa is very interesting, and is well shown in the illustrations on page 751. These figures are admirable, and will enable anyone with the aid of a good magnifier to determine the worm with certainty.
Epidemics of this worm are not infrequent.
natural size; a, head; b, tail.
The second worm we have to mention is found, as a rule, only in the two blind sacs known as the cæca. Here they often literally swarm. Like the H. inflexa, they are round, whitish worms, but they are very much smaller,
being not more than
sometimes more than Fig.5.-Female worms of Heterakis 100 of these little Fig. 6.-Male forms of Heteretis papillosa, natural size. These wretches are found
papillosa, natural size. Tbese worms are found in the two
worms are found in the long dark sacs (ceca) mainly com in a single cæcum, dark sacs (cieca) mainly co posing the posterior part of
posing the posterior part of the intestine of the fowl. which means 200 to
the fowl's intestine. 300 in a single fowl.
It is, of course, useless to argue against such a number of worms causing the fowl no inconvenience. Nevertheless, it is astonishing to find the fowls carrying this great number of parasites, in fairly good health. Not so, bowever, with young chickens. These suffer severely from even a few such worms, and many are fatal.
Again, our figures, especially those on p. 752, will enable anyone by the aid of a lens to positively identify this worm, which is technically known as Heterakis papillosa.
Treatment. The great thing to remember is that fowls become infested with worms only by means of other worms. Worms arise only from worins, and this is the whole secret of preventive measures. Of course, the fowl-parasites may in their life-history pass through other animals than fowls, but there is no evidence of this, so far, in the case of either of the worms here described. The whole question of where these worms came from, therefore, simmers down to thisWhat fowls did the worms come from? What fowls had worms, whose eggs, passing out with excrement, in some manner found their way into the fowls at present infested? Perhaps some new fowl bought and introduced into the run brought with it worms, and eggs or young of these worms were thus scattered about the run and found their way into the other fowls.
What lesson shall we learn from this? We learn this, that greater care should be taken in the disposal of hen-manure. All careful poultry-keepers clean up under the roosts frequently, because they have been taught to do so. They will be glad to find their practice upheld by such powerful arguments from the student of worms, and those poultry-keepers who have not followed the practice may now be induced to do so in the hope of extra profit, which of course arises in two ways, (1) the preservation of the manure, (2) healthier fowls with greater egg-producing powers. Connected with this subject is the raking up and occasional spading of the whole run, which is very beneficial in keeping worms in check, especially if the ran be damp.
Another matter of consequence is the arrangement of the roosts. Most of the manure collects under the roosts; it is, therefore, advisable to keep the fowls entirely away from under the roosts, which can be done by carrying wire-netting to the floor immediately under the roost, in such a manner that the droppings fall through out of reach of the fowls. The manure should not be allowed to become dry and converted into dust, for in that case it
may, in the form of dust, containing worm-eggs, blow about the yard and contaminate the food.
Never throw the fowls' food on the ground in an infested run. Have a special clear place for them to feed on, and from time to time saturate this - place with boiling water, concentrated solution of copperas, or some other powerful disinfectant.
Be especially careful with young chickens. There is where the greatest losses occur. Apply the above rules vigorously to them, and no fear need then be entertained of mysterious deaths from worms.
There is another precaution that might sometimes be taken against the infection of poultry by worms, namely, an occasional change in the run. Of course this involves some little expense. What of that, if it is recouped in eggs and poultry! Where several kinds of poultry are kept it is advisable to divide the lot up into fowls, turkeys, ducks, &c., and give each a separate run, and then from year to year change the turkeys with the fowls or ducks. The rationale of this practice is as follows:-The worms that infest fowls are, as a rule, not found in turkeys and ducks, and vice versa, so that there is little danger of infection in allowing fowls to occupy a turkey-run or a duckrun. Right here it is well to remark that if the fowl-run is so situated as during rains to drain into the turkey-run, any worm-eggs or young worms on or near the surface of the ground in the fowl-run would be washed in among the turkeys, and in that case changing the fowls to the turkey-run would be of little avail, so far as concerned keeping the fowls free from worms.
There is no doubt that moisture is necessary to advance the development of the eggs of parasitic worms after they are voided with the excrement. Any brook to which fowls have access may therefore be a fertile source of infection. It is much better to supply the fowls with water known to be good and pure. “Any water is good enough for fowls” is a bad rule to follow. Fowl-runs should be kept well drained.
Of course many of the foregoing suggestions are unnecessary, unless the fowls actually suffer from worms. Some of them, however, should always be in force, as they apply to the general health of the run regardless of worms.
There have been violent outbreaks of worms in the past, and no doubt the same will occur in future. A word as to procedure in such cases may therefore find a place here.
In the case of a violent epidemic the most urgent necessity is quarantine, Set apart a place lower down than the fowl run; all the better if it is on the side away from the prevailing wind. Into this place put all sick and suspected fowls. This separation is better both for the sick and the well ; the well are thus removed from a source of infection, while the sick, being separated, can be treated more successfully. The various suggestions given in the preceding pages should be vigorously applied to the quarantined fowls, and special precautions should also be taken with the healthy fowls. The necessity for these precautions will be well understood by those who have seen how fatal epidemics often are among fowls.
This brings us to the subject of medicines. The spectacle of a fullgrown man, with the aid of a silver spoon, endeavouring to persuade a dose of castor oil down the throat of a hen is such, that it is difficult to approach the subject in a serious spirit. Taking it for granted, however, that the novice has mastered the not difficult art of capturing a sick fowl, and opening its beak and discovering which hole the medicine should go down, a few useful remedies may be described.
Turpentine-in daily doses of not more than half an ounce is often used. A safe rule is one to three tea-spoonfuls, according to the size of the chicken, once a day for three days, and then an interval of a few days, then more turpentine, and so on, until the fowl recovers. This remedy is recommended for intestinal worms of any sort.
Areca Nut-powdered and mixed with butter or other fat may be given. It is made up into pills to which bran is often added. The dose is thirty to forty-five grains of the powdered areca nut. Any chemist will weigh out the doses. In my opinion this remedy should not be given often, or many times in succession.
Liquid male-fern extract—made into pills with bran or meal or four. Half a tea-spoonful will answer for a full-grown fowl.
These are among the best remedies, though others have been recommended. The medicines should be fresh, or they will do little good; and in general they should be followed the next day or later the same day with a tea-spoonful of castor oil.
It is better to rely on preventing than on curing.
Finally, for the benefit of specialists, I will append more complete descriptions of these worms than have been hitherto published, with a note on the young of one of the species.
2 13 52 52. 98 1. Heterakis inflexa, Rudolphi.- 6 8 1:2 2: 9 68• mm. The colourless skin is marked by plain transverse striæ, 20u apart, and on the margin of the body shows a crenate contour. There are no hairs or other appendages on the skin. The head is marked off by a trifling constriction, and is somewhat rounded in front, being devoid of cephalic setæ. The mouth is surrounded by three lips, each of which is three-lobed, the middle lobe being the largest. Apparently there are two low circular papillæ on the dorsal lip, and one each, broad and low, on the two submedian lips. There are no organs of vision, and apparently no lateral organs, at any rate the latter cannot be conspi. cuous. The pharynx is of a form natural to three large, somewhat hemi. spherical lips. The æsophagus assumes the following dimensions: just behind the pharynx it is one-third as wide as the neck; at a distance from the base of the pharynx equal to the width of the head, it swells a little, and then narrowing a little, proceeds, conoid, to the cardiac constriction, where it diminishes in a clavate manner, as shown in I, Fig. 7. The lining of the æsophageal tube shows, for the most part, as three longitudinal lines. The cardiac constriction is broad, and measures one-third as great as the corresponding body-width. The cardia is very flat, and there is no distinct cardiac cavity. The intestine is about one-third as wide as the body, and ends posteriorly in a rectum twice as long as the body is wide. The ventral excretory pore is located just behind the somewhat oblique nerve-ring. The longitudinal fields are one-third as wide as the body, and are coarsely granular in structure. The irregularly conoid tail ends in a blunt terminus, bearing an inconspicuous button. The anal region is & little elevated, as is also the region of the vulva. In a female 73 millimetres long the uterus was one-fourth to one-half a millimetre wide and 33 millimetres long. It was directed forward for 1} millimetres of its length, and then backward for another 11 millimetres, when it became bifurcate, the two branches extending in opposite directions half-way to the head, and half-way to the tail, then back to near the vulva. The eggs contained in the uterus are 48-52 x 73-82 H and are surrounded by an apparently structureless shell 4-5 u thick. The eggs begin gastrulation while in the uterus, and may possibly, before being laid, go on to the formation of an embryo.