Techniques for the long-term collection of lymph from the unanaesthetized foetal lamb in utero.

Abstract

SummarySurgical techniques are described for establishing chronic fistulae in the thoracic, intestinal, lumbar and popliteal lymph ducts of foetal lambs in utero. These fistulae have remained patent and enabled lymph to be collected for periods of up to 5 days. The Iambs have been born spontaneously or delivered by Caesarean section with their fistulae intact and still flowing.Lymph flow rates were 9–18 ml./hour from the thoracic duct, 2.8–8.6 ml. /hour from the intestinal duct, 2.8–9.2 ml./hour from the lumbar trunk and 0.6 ml./hour from the popliteal duct.The protein concentration of foetal thoracic duct lymph was 2.30 g./100 ml. immediately after cannulation, the intestinal lymph 2.37 g./100 ml. and the lumbar lymph 2.12 g./100 ml.The cells of foetal lymph were almost all small and medium lymphocytes and only an occasional cell was found in mitosis. Drainage of the thoracic duct lymph for 36 hours drastically reduced the number of lymphocytes in the lymph, suggesting that, as in the adult sheep, most of the lymphocytes in foetal lymph are recirculating cells.