290 
SURGERY AND TRANSPLANTATION 
Horse anti-bovine lymphocyte serum (ALS) 
was prepared by the injection of bovine lymph- 
ocytes in horses. The lymphocytes were col- 
lected, by the technique of Chanana and 
Cronkite,*' from the thoracic duct of clinically 
normal calves. The lymphocytes were separated 
from the lymph by low speed centrifugation, 
washed twice in Hank's balanced salt solution 
and injected into horses. On 3 occasions, 14 
days apart, each horse received approximately 
75 X viable lymphocytes by intravenous 
injection and 7 to 10 days after the third injec- 
tion it was exsanguinated. The blood was al- 
lowed to clot and the serum separated and 
heated to 56° C for 30 minutes to inactivate 
complement. Merthiolate 1 : 10,000 was added as 
a preservative and the serum was stored at 
-10°C. 
Treatment of calves with ALS was started 6 
days before transplantation of allografts and 
xenografts. The calves were given approxi- 
mately 2 ml/kg of ALS subcutaneously either 
daily or every second day. 
The calves given prednisolone acetate re- 
ceived 1 mg/kg daily ; the time of the first dose 
ranged from 2 days before to 2 days after sur- 
gery. Dosage was reduced to 0.5 mg/kg 14 days 
after transplantation. 
To study the host's immunologic response to 
a heart xenograft and determine the capability 
of ALS to suppress rejection, goat hearts were 
transplanted, heterotopically to the thorax of 
calves. A technique was developed that permit- 
ted transplantation of the goat heart with less 
than 30 minutes ischemia after it was taken 
from its primary host. With this technique, the 
goat heart was removed and flushed with 1 liter 
of saline at 4° C containing 10 units/ml of hep- 
arin. The brachiocephalic and pulmonary ar- 
teries were joined by end-to-side anastomoses to 
the brachiocephalic and pulmonary arteries of 
the calf through a left intercostal thoracotomy. 
RESULTS AND DISCUSSION 
Male calves of dairy breeds (Holstein, Ayr- 
shire, or Guernsey) weighing 160 to 180 pounds 
were preferred to calves of beef breeds. Beef 
calves were .indesirable because they were more 
difficult to handle, had a smaller thoracic cavity 
and had more perivascular fat which compli- 
cated dissection. Males were preferred as fe- 
males were often culled from a herd because of 
illness, whereas male calves were commonly 
reared carefully for veal production and were 
sold in excellent condition. Calves in excess of 
150 pounds were usually weaned from milk (or 
a milk substitute) and were functioning as 
ruminants. Thus, they required only grain,° 
hay, water and salt^ ad libitum. In addition, 
these older calves seemed more resistant to pul- 
monary complications during ventilation and 
cardiopulmonary bypass. We found it better to 
use weaned calves that occasionally bloated (see 
below) because they were less prone to pulmon- 
ary complications during surgery. 
During inhalation anesthesia, ventilation and 
thoracotomy special attention must be given to : 
(1) controlling ruminal distension (bloat) and 
excessive secretion that may obstruct airways, 
(2) induction of anesthesia, (3) intubation, 
hay, water and salt^ ad libitum. In addition, 
and (4) maintenance of normal acid-base bal- 
ance and oxygen tension. 
Abdominal distension in the calf results from 
continuous fermentation and accumulation of 
gas in the rumen during surgery.'^ Because of 
the calf's rather small thoracic cavity, abdomi- 
nal distension severely impairs pulmonary func- 
tion and decreases venous return from the cau- 
dal vena cava. Ruminal distension and the 
possibility of regurgitation and inhalation pneu- 
monia during induction of anesthesia were re- 
duced by withholding food for 24 hours before 
surgery to decrease the amount of fermentable 
material. In addition, the rumen, which is on 
the left side, was decompressed if it became dis- 
tended during or after surgery; this was done 
with a 14 gauge, 2 inch needle, inserted into the 
rumen through the left flank caudal to the last 
rib. A piece of rubber tubing was attached to 
the needle and the free end was placed under 
water to control the odor. 
During anesthesia there was increased secre- 
tion of saliva and tracheal and bronchial mucus 
which if allowed to accumulate would have im- 
paired ventilation. Secretion was effectively 
stopped by the preanesthetic administration of 
" Calf Startena, Ralston Purina Co., Checkerboard Square, St. 
Louis, Missouri. 
E Salt Brick Morton Salt Company, Chicago, Illinois. 
