292 
SURGERY AND TRANSPLANTATION 
Diarrhea was a particularly serious condition 
in the calf. It resulted in rapid dehydration and 
severe metabolic acidosis. When it occurred, 
fluid was given intravenously at a rate of up to 
150 ml/kg/24 hr, depending upon the severity 
of the diarrhea. The metabolic acidosis was 
treated with sodium bicarbonate based on either 
acid-base determinations on arterial blood or on 
estimates of bicarbonate deficit.^^ 
Immediately after operation the calves were 
placed in sternal recumbency and the lungs 
were hyperinflated to expand areas of atelec- 
tasis. The endotracheal tube was removed, after 
the laryngeal reflex had returned, without de- 
flating the cuff so as to remove any ingesta that 
had accumulated in the trachea above the cuff. 
The calf was given oxygen through a nasal tube 
if after surgery the PaOo of the calf while 
breathing room air was less than 70 mm. Hg. 
Five liters per minute of oxygen were adminis- 
tered through a polyethylene catheter placed 
approximately 15 cm. into a naris and secured 
to the external naris with a simple interrupted 
suture. 
During intrauterine development, the calf 
produces only small amounts of immuno- 
globulins--^'* insufficient to protect it against 
postnatal infection. Thus, for defense against 
diseases, the neonatal calf must rely on 
the immunoglobulins obtained soon after birth 
from the dam's colostrum.^^'^^ When a related 
ruminant, the fetal lamb, is given allogeneic 
skin grafts at 85 days or later in gestation they 
are rejected and have a mononuclear cell 
infiltrate.^'^ The cellular immune response of 
the neonatal calf to genetically foreign skin and 
organ grafts is prompt and vigorous and is pre- 
sumably present in utero. A breed difference 
has been noted in the humoral antibody re- 
sponse of newborn calves. 
Suppression of the cellular immune response 
of calves with a number of immunosuppressive 
agents has been reported. It has been possible to 
prolong the survival of allografts and xeno- 
grafts and tumor transplants with whole-body 
irradiation, i« by depletion of lymphocytes,^^ 
and with antilymphocyte serum (ALS) either 
alone or with prednisolone.^^ 
Marshak et al.i» successfully transplanted 
lymphosarcoma from cows to unrelated calves 
given 200 rads of whole-body irradiation but 
the rate of success was low, and the mortality 
rate from the effects of irradiation was high. 
Depletion of lymphocytes by extracorporeal 
irradiation of lymph^" prolonged the survival 
of skin allografts for 20 days. This technique, 
however, is impractical for organ transplant 
studies. 
In the calf ALS is superior to other 
immunosuppressants.^^ It has prolonged the 
survival of skin allografts and xenografts and 
heart xenografts. Its use also permitted the suc- 
cessful transplantation of bovine lymphosar- 
coma.-- 
The ALS caused a febrile response, depres- 
sion of the total leukocyte and absolute lympho- 
cyte counts (Figure 1). Discontinuation of ALS 
treatment resulted in graft rejection after a 
gradual increase in the total leukocyte and abso- 
lute lymphocyte counts. Continued administra- 
tion of ALS resulted in thrombocytopenia and a 
gradual decrease in the packed cell volume. 
During ALS treatment calves were able to re- 
spond to bacterial infection with a neutrophilia 
(Figure 2). 
Bacterial infections in ALS-treated calves 
were, in most instances, easily controlled with 
antibiotics. It was impossible to prevent or 
treat, however, polyarthritis caused by Myco- 
plasma hovimastitidis in ALS-treated calves. 
The onset of the arthritis was sudden, and 
Figure 1. — Changes in the total leukocyte and absolute 
lymphocyte counts of calves given 2 ml/kg of ALS 
every second day. 
