Definition. Causes: bleeding, watery repair, hydroæmia, repair of
globules, changes in red globules, in bone marrow. Cause of
chronicity; profuse secretions; moplasms; parasites; chronic
exhausting diseases; defective diet or hygiene; diseases of jaws or
throat; overwork; toxic substances. Symptoms: pallid mucosæ, weakness,
perspiration, soft tissues, small pulse, palpitation, anæmic
heart—arterial and venous murmurs, depilation, indigestion,
costiveness, urine clear, abundant, emaciation. Lesions: blood poor in
globules, embryonic, and other abnormal red globules, fatty
degeneration, blood clot. Treatment: remove causes, diet, hygiene,
sunshine.
_Definition._ Bloodlessness; Deficiency of blood; Lack of red blood
globules. The last named is the condition to which the term is
habitually applied.
_Causes._ Anæmia is not so much a disease, as a result of a great many
debilitating and exhausting conditions. =Hæmorrhage= the most direct
cause of anæmia determines at first an actual lack of blood (oligæmia)
and of blood pressure, which may be sufficient to cause fainting and
death. In case of survival the amount of blood is rapidly made up by
absorption from all available sources of liquid in the economy, but the
blood so restored is essentially hydroæmic having an excess of water and
a lack of globules and dissolved solids. If however the loss has been
moderate the quality may be restored in a few days. Buntzen found that
after moderate bleeding the volume is restored in a few hours; after a
profuse hæmorrhage in 24 to 48 hours. After bleeding to 1.1 to 4.4 per
cent. of the body weight the increase of the red globules may be noticed
after 24 hours, and is completed in 7 to 34 days. It is noteworthy that
during this repair the bone marrow becomes much redder and more
cellular, and that new red cells found in the blood are nucleated
(Neumann) and contain less hæmoglobin (Ott). The absence of hæmoglobin
is nearly in proportion to the amount of the hæmorrhage (Bizzozero,
Salvioli). If the hæmorrhage is slow and continuous this repair is
counterbalanced and the anæmia is much more persistent.
=Profuse secretion= as of milk (cows, goats, ewes, bitches, on poor
feeding), of liquid fæces, urine, or pus often determine a marked and
even dangerous anæmia.
The rapid growth of multiple =tumors= as of _melanosis_ in gray horses
has been noticed to cause profound anæmia (Bouley).
Perhaps no cause is more potent than the attacks of =parasites= and
especially such as live by sucking the blood. The numerous strongyli of
the lungs, stomach, and intestine, the tricocephalus, and allied round
worms, the trematodes of the liver, and the cytodites of birds furnish
striking examples of the bloodless and debilitated condition which they
may produce. In man ankylostomata causes anæmia in Egypt, Italy (St.
Gothard) and elsewhere, and bothriocephala in different countries.
=Chronic exhausting diseases= especially those which affect the
digestive organs and mesenteric glands are prolific causes. So with
Bright’s disease.
Connected with these are =defects in diet or hygiene=. Starvation,
unsuitable, innutritions, or indigestible food, too laxative food, damp,
dark, draughty or unventilated stables, and irregularity in feeding,
watering and work are all potent factors in inducing anæmia.
=Diseases of the masticatory apparatus= (broken jaw, diseased teeth,)
preventing the preparation of food, and pharyngeal troubles interfering
with deglutition are other causes. Finally overwork is not to be
forgotten.
=Toxic anæmia= may occur from the ingestion of lead, mercury, or
arsenic.
_Symptoms._ These may be little marked at the outset in slowly
developing cases. Extra pallor of the mucous membranes, fatigue and even
breathlessness on slight exertion, a small, weak, pulse, with a tendency
to become rapid, with violent heart beats, when excited.
At a more advanced stage the mucosæ, especially the buccal, are pale and
thin, the muscles are soft, flabby and weak, fatigue and perspiration
are easily induced, the feet are advanced more nearly in the median line
of the body, and the toes strike on any obstacles, the pulse is weak,
small and quick, and the heart easily excited even to palpitation, and
with an occasional anæmic murmur with the first heart sound. Arterial
and venous murmurs may be present. The hairs are easily detached.
Appetite and digestion fail, there is costiveness, a full secretion of
urine of a clear aspect, the subcutaneous fat disappears and the skin
feels thin and limp (paper skin in sheep), the hair dry and lusterless,
the wool flattened (clapped). The weakness and emaciation go on
increasing and dropsies appear in the limbs, under the trunk and jaw and
in the internal cavities.
_Pathology._ _Lesions._ Apart from the causes, the morbid conditions are
mainly found in the blood. The watery state of the blood, the lack of
red globules (even to but 2,000,000 per cubic millimeter), the absence
of albumen (76 per 1000 in place of 83), the loose coagulum with excess
of buffy coat, and the excess of serum are characteristic. The presence
of large, nucleated (myelogenous) red cells, of spherical bodies smaller
than the normal red cells (microcytes), and of irregularly shaped red
cells (poikilocytes) is characteristic, the latter especially of
pernicious anæmia. As the disease advances fatty degeneration of heart,
liver, kidneys, and other organs are complications and tend to aggravate
the disease, by counteracting repair of the globules—thus establishing a
vicious circle. All the organs are pale and flaccid, the arteries empty,
the veins contain a little blood, forming pale clots. In the cases
considered, all the result of another disease, the lack of blood and of
the solid and vital elements in that which remains, entails imperfect
function in all the vital processes, including sanguification itself,
and in this way an anæmia once established tends to perpetuate and
aggravate itself.
_Treatment._ The anæmia above considered being largely symptomatic, or
resultant from other diseases, the first consideration as regards both
prevention and treatment is to prevent or cure such diseases. Where
dietetic or hygienic, a liberal diet, and good hygiene will meet every
demand in the early stages. In the warm season an open air life is most
important. In case of a drain by over-secretion (milk) this must be
judiciously checked. In bitches it will often be needful to wean several
of the puppies. A rich and very digestible diet (oats, beans, linseed,
oil meal, milk, gruel), in small compass, and suited to the genus and
individual, with iron and bitters, and in the herbivora carminatives,
will suit many cases. Muriate of iron, with strychnine or nux vomica;
iron sulphate, sodium chloride and nux; or dialysed iron, or some other
soluble ferruginous salt, with quinia, gentian, or some other bitter
will serve a good purpose. For the dog saccharated carbonate of iron or
citrate of iron and ammonia with quinia or strychnine, in pill form, is
convenient. With poor digestion muriatic acid and pepsin may replace the
iron at first. Beef teas may often be given with advantage, even to the
herbivora, and injections of defibrinated ox blood night and morning
have proved of service. In extreme anæmia, as from hæmorrhage,
transfusion, or its equivalent, must be resorted to. A normal saline
solution (0.6 per cent. NaCl), boiled, may be thrown into the peritoneum
or subcutaneous connective tissue, or defibrinated blood, may be
injected into the peritoneum. Transfusion is the dernier resort.