on Alfalfa Pasturage

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					   Tympany in Cattle with Special
Reference to its Occurrence while Grazing
         on Alfalfa Pasturage
                               By R. A. MCINTOSH,*
T YMPANY-an excessive accumulation of gases in the rumen-is doubt-
      less the most common digestive ailment affecting the bovine species.
     Under normal conditions a small amount of gas accumulates which is
regurgitated. But when the physiological function of the rumen is disturbed
by an excessive food intake or for other reasons, its contents undergo fer-
mentation with the consequent liberation of a large amount of gas. This not
being regurgitated as rapidly as formed soon distends the walls of the organ
to an extent which paralyses movement and consequently normal regurgita-
tion becomes impossible. Further the distended organ by pressure on the
diaphragm rapidly brings about asphyxia.
      Little if any literature on the subject is seen in Veterinary periodicals
at the present time. There are, however, certain other features of the con-
dition which Veterinarians should have knowledge of and which are worthy
of consideration. These have reference to the occurrence of bloat and its
etiological factors particularly when cattle are grazing on alfalfa.
      Previous to the 1937 season there were a number of years in which
prolonged dry spells of weather occurred in Ontario. During those seasons
large numbers of cattle were lost as a result of bloat. At times, on some
farms, the owners were forced to keep a constant watch over their herds.
Some farmers sold their herds because of the difficulty they were experi-
encing with the condition. In these instances it was not a case of one or two
animals bloating, rather whole herds were affected and created a serious
condition for the farmers concerned.
      Literature on the subject refers to the causes of tympany as being the
overeating of succulent food. Veterinarians know that an overfeed of chop
or any other food that has fermenting possibilities will give rise to bloating.
Among the pasturages provided for animals the legumes are most danger-
ous, particularly when cattle are first turned into such forage and also when
 it is damp or wet. Of the legumes used for pasture alfalfa occupies the
premier place wherever it can be successfully grown. While it is admitted
that bloating may occur when cows are first turned in on it also when it is
wet and damp, this is not half of the story for these theories regarding this
 legume in particular are not constant. As a matter of fact, on those oc-
 casions referred to when large numbers of animals were affected, the cattle
had been on alfalfa regularly and they would bloat whether the forage was
  *Dr. R. A. McIntosh, Ontario Veterinary College, Guelph, Department of Diseases of Cattle,
  Obstetrics and Therapeutics.
OCTOBER, 1937                                                           VOL. I -No. 1    23
wet or dry. It occurred during drouths when there was little or no moisture
either in the form of rain or dew.
                      Possible Connection with Soil Fertility
      It is not easy to explain why bloat should occur with great frequency
under these circumstances but the writer is inclined to the belief that it
may depend upon chemical factors within the plant itself rather than any
other feature. In discussing the matter with keen and observant live stock
men certain significant items have been learned. Among these is the fact
that if the alfalfa is grown on land that has been fertilized and properly
farmed, cows may pasture on it day in and day out with impunity. The fol-
lowing incident will afford a practical illustration.
     An Oxford County farmer who keeps his land in a high state of fertility
pastured his cows on alfalfa without having any trouble with bloat. His
son had purchased an adjoining farm which had become badly run down
and his cows on an alfalfa pasture just over the fence were bloating. They
undertook a simple experiment. The son's bloating cows were put in the
home pasture and the father's cows which had not bloated were put in the
pasture on the rundown farm. Now the disease picture changed in so far as
the cows were concerned for the father's cows began to bloat while the
son's cows became normal. It is obvious that the reason must exist in the
clover itself.
     On another farm, a farmer was having so much trouble with bloat in
his herd that he sold the whole herd to another farmer who took them home
and put them on alfalfa pasturage where the land was in a good state of fer-
tility. No further bloating occurred in this group of animals. The farmers
who have the least trouble with bloating are those whose alfalfa fields are
in a high state of fertility, while those who have the greatest amount of
trouble are farmers whose pasture land is in a worn-out condition. This
feature may be looked upon as one of the most important when bloating
occurs while cattle are on alfalfa.
                           Effective Treatment Varies
      There are other features which are worthy of consideration. Regardless
of how good alfalfa may be, cows prefer grasses. How often it will be ob-
served where there is a little grass growing in an alfalfa field that it is kept
cropped down closely! Moreover, where both forms of pasturage are avail-
able the cattle will spend more time on the grass and keep it eaten down
closer than the alfalfa. This means that the grass is more palatable, more
acceptable to them, and more satisfying. If then they are on a pasture where
nothing but alfalfa is available it is not reasonable to assume that the cattle
may eat more alfalfa than they should in their desire to satisfy their appe-
tite. Again if cows are kept in the barns too long in the mornings at milking
time and they are turned back on the alfalfa when they are excessively
hungry, they may eat too much before stopping to ruminate. If they had
been fed a little grain or dry roughage to appease their hunger before going
to the pasture the likelihood of bloat would have been greatly reduced. If
the pasture in which cows graze is without shade, bloating will sometimes
occur particularly in excessively warm weather. Excessive warmth may
lend itself to bloating in two ways. It causes the alfalfa to wilt and the
consumption of wilted forage is in the writer's opinion just as dangerous
as wet forage. The excessive heat also affects the cattle. If there is no shade
available, the cattle may be observed standing about with their hair on end,
dull and unquestionably affected by the heat. Under these circumstances,
their digestive tract is not functioning, they do not ruminate and bloating
may follow. All of these little things have their significance when consider-
ing the circumstances under which bloating occurs while cattle are on legu-
minous pasturage.
                         Other Factors Worth Considering
      The treatment of this form of bloat is much the same as that occurring
from other causes. However, with this type of disease the Veterinarian
must act quickly. The first object in treatment in all cases where there is
immediate danger of asphyxia is to relieve the distended organ. This is
probably most quickly accomplished by the use of a trocar.
      Another method consists of standing the animal high in front and pass-
 ing a stomach tube. While the tube is in position, two quarts of water con-
taining an ounce of creolin may be pumped into the rumen. The tube should
be moved back and forth so as to distribute the creolin solution here and
 there throughout the cavity of the rumen. The creolin solution very ef-
 fectually arrests fermentation. When using the stomach tube to reduce
 bloat the purpose of standing the animal high in front is to allow the solid
 contents of the rumen to gravitate to the rear. This will bring the gas for-
 ward so that the moment the tube enters the rumen the gas escapes and
 the distention is overcome in a remarkably short time. 'The tube may plug.
 with ingesta and if it does, a little water should be pumped through it, the
 pump disengaged and thus allow the gas to escape. In simpler cases a car-
 minative and antacid drench is all that is required.
      In some instances where the gas is mixed with the ingesta and the
 whole rumen content is a seething, fermenting mass, the trocar does not
 give the measure of relief desired. If extreme distention has occurred under
 such circumstances a rumenotomy should be performed to allow the con-
 tents to spill out as quickly as possible. Before opening the rumen suture
 its walls to the skin incision so as to prevent food getting into the peritoneal
 cavity. Where a large number of animals are affected at the same time the
 Veterinarian would likely use different methods of tratment depending
 upon the severity of the different cases.
       It would be interesting to have practitioners submit.their methods of
 treatment for this condition for the sake of comparison and for the benefit
  of others.
      Unity promotes concord-community of interests, the same aims, the
  same objects give, if anything can, a feeling of comradeship, and the active
  co-operation of many men, while it favours friction, lessens the chances of
  misunderstanding and ill will.-Osler.
 OCTOBER, 1937                                                 VOL. I -No. 1   25
                        Dr. J. B. Collip, whose article on "The Endocrine
                        Glands and their Products-the Hormones" appears
                       in the current issue is a native of Belleville, Ontario
                        and a graduate of the University of Toronto. Since
                        graduation he has held the posts of lecturer and pro-
                        fessor at the University of Alberta. He came to
                        McGill University in 1927 and is now head of the
                        Department of Biochemistry in that institution.
                        Recognition of his eminence as a biochemist is in-
                        ternational. At home he has been honoured by the
                        Canadian Medical Association, Royal Society of
                        Canada and the University of Manitoba; in the Uni-
                        ted States by Harvard University and the University
                        of Pennsylvania and in Britain by the Royal Society
                        ind Edinburgh University. The Senate of the latter
institution recently selected him to receive the Cameron Prize which is an-
nually awarded to one who during the five years immediately preceding
"has made a highly important and valuable addition to practical thera-

                 Animal Diseases Research Institute, Hull, Quebec.


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