Re trichinellosis in Georgia swine. We had only limited opportunity
to examine seropositive swine at slaughter. We obtained diaphrams
from a number (don't recall the exact figure, but between 20 and 40)
of either seropositive swine or swine from seropositive herds. By
digesting the entire diaphragm, we recovered larvae from only 3 sows.
They harbored, 1, 1, and 2 in the entire diaphragm. What does this
mean? I am uncertain. Possibly other larvae were calcified in the
tissue and were not revealed by the digestion procedure, or possibly
the swine had a wildlife species of Trichinella.
My graduate student, Dr. Kelly Mann, isolated Trichinella T5 from a
bobcat here in Georgia and identified it using DNA technics. Mr.
ChaoQun Yao, another student, has examined the infectivity of T5
versus that of T1 (spiralis). In swine he found that administration
of T5 caused seroconversion at 5 weeks after infection in contrast to
3 wai for spiralis. But, at necropsy 8 wai, T5 could NOT be
recovered from any of the tissues digested. There were also
differences in infectivity and fecundity in various laboratory hosts.
Of interest, examination of several immunodominant antigens by
recombinant DNA technics reveal few (less than 5% difference) in the
antigen sequences. Swine infected with spiralis cross-react with T5.