Common Diseases of Farm Animals Part 9

_The preventive treatment_ consists in avoiding conditions that may favor or cause an inflammation of the gland. Animals that have highly developed mammary glands should be fed a light diet just before and following parturition. Following parturition, a dose of Epsom or Glauber's salts may be given. If the young does not take all the milk, the udder should be milked out as clean as possible. Ma.s.saging the udder by kneading or stroking may be practised.

The following _treatment_ is recommended: The application of a thick coating of antiphlogistin once or twice daily is a useful remedy. If the udder becomes badly swollen, it should be supported with a bandage.

Extensive inflammation may be treated by the application of cold in the form of packs of cracked ice. Irrigating the gland with a four per cent water solution of boric acid is an important treatment for certain forms of mammitis. Abscess formation or suppuration should be promptly treated by opening and treating the abscesses. If gangrene occurs, it may be necessary to remove a part, or the whole of the udder.

The giving of milk discolored with blood may be treated by applying camphorated ointment twice daily.

SORE AND WARTY TEATS.--Irritation to the teats by filth, cold, moisture and injuries cause the skin to become inflamed, sore and scabby.

_Preventive treatment_ is the most satisfactory. Sore teats may be treated by applying the following ointment after each milking: vaseline ten parts and oxide of zinc one part. Pendulous warts may be clipped off with a sharp pair of scissors. Castor oil applied to the wart daily by rubbing may be used for the removal of flat warts.

"MILK-FEVER" OR POST-PARTUM PARALYSIS.--This is a disease peculiar to cows, especially heavy milkers that are in good condition. It most commonly occurs after the third, fourth and fifth calving. The disease usually appears within the first two or three days after calving, but it has been known to occur before, and as late as several weeks after calving. The cause is not certainly known. The Schmidt theory is that certain toxins are formed in the udder, owing to the over activity of the cells of the glandular tissue.

[Ill.u.s.tration: FIG. 20.--A case of milk-fever.]

_The symptoms_ are characteristic of the disease. At the very beginning of the attack the cow stops eating and ruminating, becomes uneasy, switches the tail, stamps the feet, trembles, staggers when forced to walk and finally falls and is unable to get up. At first she may lie in a natural position; later, as the paralytic symptoms become more p.r.o.nounced, the head is laid against the side of the body and the animal seems to be in a deep sleep (Fig. 20). In the more severe form the cow lies on her side, consciousness is lost and the paralysis of the muscles is marked. The different body functions are interfered with; the urine is retained, bloating occurs, respirations are slow, pulse weak and temperature subnormal or normal.

_Preventive treatment_, such as feeding a spare diet during the latter period of pregnancy, is not always advisable. Heavy milkers should be given one-half pound of Glauber's salts a day or two before calving, and the dose repeated when the cow becomes fresh. Cows affected with milk-fever seldom die if treated promptly.

The _treatment_ consists in emptying the udder by milking and injecting air or oxygen gas into the gland until it is completely distended (Fig. 21).

The milk-fever apparatus should be clean, and the air injected filtered.

Before introducing the milking tube into the milk duct, the udder should first be washed with a disinfectant, and a clean towel laid on the floor for the gland to rest on. After injecting the quarter, strips of muslin or tape should be tied around the ends of the teats to prevent the escape of the air. If the cow does not show indications of recovery in from four to five hours, the treatment should be repeated.

[Ill.u.s.tration: FIG. 21.--Milk-fever apparatus: pump; filter; rubber tubing; and milk tube.]

It is very necessary to give the cow a comfortable stall and protect her from any kind of exposure. No bulky drenches should be administered. If she lies stretched out, the fore parts should be raised by packing straw under her. This is necessary in order to prevent pneumonia, caused by regurgitated feed entering the air pa.s.sages and lungs. It is very advisable to give her the following mixture for a few days after the attack: tincture of nux vomica two ounces, and alcohol six ounces. One ounce of this mixture may be given four times daily in a little water.

QUESTIONS

1. Name the generative organs of the female.

2. Name the generative organs of the male.

3. Give the causes of sterility or impotency in the male and female.

4. Give the treatment of impotency in the male and female.

5. Describe the probable signs of pregnancy; positive signs of pregnancy.

6. Describe the hygienic care of the pregnant female in a general way.

7. Name the different forms of abortion; give the causes.

8. Describe the preventive treatment of infectious abortion.

9. Give a general discussion of the physiology of parturition.

10. What are the common causes of difficult birth?

11. What parts of the foetus may present themselves at the inlet of the pelvic cavity? What are the different positions of the foetus?

12. What attention should be given the mother at the time of parturition?

13. What attention should be given the young immediately after birth?

14. Give the causes of retention of the fetal membranes; state the method of removing them.

15. Give the causes and treatment of inflammation of the udder.

16. Give the cause of milk-fever; give the treatment.

CHAPTER VIII

DISEASES OF THE RESPIRATORY APPARATUS

GENERAL DISCUSSION.--The respiratory apparatus may be divided into two groups of organs, anterior and posterior. The anterior group, the _nostrils, nasal cavities, pharynx, larynx_ and _trachea_, is situated in the region of the head and neck. The posterior group, the _bronchial tubes_ and _lungs_, is situated in the chest or thoracic cavity.

_The nostrils_ are the anterior openings of the air pa.s.sages. The nasal cavities are situated in the anterior region of the head, and extend the entire length of the face. Each cavity is divided into three long, narrow pa.s.sages by the two pairs of turbinated bones. The lining membrane is the nasal mucous membrane, the lower two-thirds or respiratory portion differing from the upper one-third, in that the latter possesses the nerve endings of the olfactory nerve and is the seat of smell. The five pairs of head sinuses communicate with the nasal cavities. Posteriorly and near the superior extremity of the nasal pa.s.sages, are two large openings, the guttural, that open into the pharyngeal cavity.

_The pharynx_ is a somewhat funnel-shaped cavity. The walls are thin and formed by muscles and mucous membrane. This is the cross-road between the digestive and respiratory pa.s.sages. In the posterior portion of the cavity there are two openings. The inferior opening leads to the larynx and the superior one to the oesophagus. All feed on its way to the stomach must pa.s.s over the opening into the larynx. It is impossible, however, for the feed to enter this opening, unless accidentally when the animal coughs. The cartilage closing this opening is pressed shut by the base of the tongue when the bolus of feed is pa.s.sed back and into the oesophageal opening.

_The larynx_ may be compared to a box open at both ends. The several cartilages that form it are united by ligaments. It is lined by a mucous membrane. The posterior extremity is united to the first cartilaginous ring of the trachea. The anterior opening is closed by the epiglottis. Just within is a V-shaped opening that is limited laterally by the folds of the laryngeal mucous membrane, the vocal chords.

_The trachea_ is a cylindrical tube originating at the posterior extremity of the larynx, and terminating within the chest cavity at a point just above the heart in the right and left bronchial tubes. It is formed by a series of cartilaginous rings joined together at their borders by ligaments and lined by a mucous membrane.

_The bronchial tubes_ resemble the trachea in structure. They enter the lungs a short distance from their origin, where they subdivide into branches and sub-branches, gradually decreasing in calibre and losing the cartilaginous rings, ligaments and muscular layer until only the thin mucous membrane is left. They become capillary in diameter, and finally open into the infundibula of the air cells of the lungs.

_The lungs_ take up all of the s.p.a.ce in the thoracic cavity not occupied by the heart, blood-vessels and oesophagus. This cavity resembles a cone in shape that is cut obliquely downwards and forward at its base. The base is formed by the diaphragm which is pushed forward at its middle. It is lined by the pleura, a serous membrane, that is inflected from the wall over the different organs within the cavity. The median folds of the pleura divide the cavity into right and left portions. A second method of describing the arrangement of the pleura is to state that it forms two sacks, right and left, that enclose the lungs. The lungs are the essential organs of respiration. The tissue that forms them is light, will float in water, is elastic and somewhat rose-colored. Each lung is divided into lobes, and each lobe into a great number of lobules by the supporting connective tissue. The lobule is the smallest division of the lung and is formed by capillary bronchial tubes, air cells and blood-vessels. It is here that the external respiration or the exchange of gases between the capillaries and the air cells occurs.

VENTILATION.--It is agreed by all persons who have investigated the subject, that unventilated stable air is injurious to animals. At one time it was believed that the injurious effects resulting from the breathing of air charged with gases and moisture from the expired air and the animal's surroundings, were due to a deficiency in oxygen. It is now believed that the ill-effects are mainly due to the stagnation of air, the humid atmosphere, and the irritating gases emanating from the body excretions.

The common impurities found in _stable air_ are carbonic and ammonia gas, moisture charged with injurious matter and dust from the floor and bodies of the animals. As a rule, the more crowded and filthy the stable, the more impurities there are in the air. If any of the animals are affected with an infectious disease, such as tuberculosis or glanders, the moisture and dust may act as carriers of the disease-producing germs. Infectious diseases spread rapidly in crowded, poorly ventilated stables. The two factors responsible for this rapid spread of disease are the lowered vitality of the animal, due to breathing the vitiated air, and the greater opportunity for infection, because of the comparatively large number of bacteria present in the air.

_The purpose of stable ventilation_ is to replace the stable air with purer air. The frequency with which the air in the stable should be changed depends on the cubic feet of air s.p.a.ce provided for each animal, and the sanitary conditions present. The princ.i.p.al factor in stable ventilation is the force of the wind. In cold weather it is very difficult to properly ventilate a crowded stable without too much loss of animal heat and creating draughts.

For practical purposes, the _need of ventilation_ in a stable can be determined by the odor of the air, the amount of moisture present and the temperature. It is impossible to keep the air within the stable as pure as the atmosphere outside.

All dangers from injury by breathing impure air, or by draughts can be eliminated by proper stable construction, attention to the ventilation and keeping the quarters clean.

[Ill.u.s.tration: FIG. 22.--A case of catarrhal cold.]

CATARRH (COLD IN THE HEAD).--Catarrh is an inflammation of the mucous membrane lining the nasal cavities that usually extends to the membrane lining of the sinuses of the head. It may be acute or chronic. The inflammation very often extends to the pharynx and larynx. Cold in the head is more common in the horse than in any of the other animals (Fig. 22).

_The most common causes_ of "colds" are standing or lying in a draught, becoming wet, and exposure to the cold. "Colds" are common during cold, changeable weather. Horses that are accustomed to warm stables, are very apt to take "cold" if changed to a cold stable and not protected with a blanket. Most animals are not affected by the cold weather if given dry quarters and a dry bed. Irritation to the mucous membrane by dust, gases and germs is a common cause. Influenza and colt distemper are characterized by an inflammation of the respiratory mucous membranes. In the horse, chronic catarrh is commonly caused by diseased teeth, and injuries to the wall of the maxillary sinus. In sheep, the larvae of the bot-fly may cause catarrh.