Research Results - (PDF, 101 mb) - USAID

Other Contributions
Contributions To U.S. Agriculture
1. Studies on genetic resistance to H. contortus
by goats in Kenya are directly applicable to U.S.
sheep and goats. The studies on vaccination
against H.contortus also are directly applicable
to small ruminants in the U.S.
2. The DNA probe for C.ruminantiumorganisms
can be used to help prevent entry of this
disease into the U.S. This preventive measure is
important because heartwater occurs in some
Carribean islands.
Contributions To Host Country Agriculture
Contributions are listed under achievements,
Linkages and Networking
We believe that our work with CCPP has
direct application to other countries because of
the occurrence of clinical signs of the disease in
at least 33 countries in Africa, the Middle East,
and western Asia. Morbidity and mortality
rates of 100% and 68%, respectively, in susceptible
herds made development of an appropriate
vaccine an important priority. To extend the use
of the vaccine SR-CR5P scientists have developed,
it is necessary to document the presence
of F38 (the putative causative agent of CCPP) in
countries where the disease occurs. To date, F38
has been isolated from CCPP cases in Sudan,
Tunisia, South Yemen, Chad, and Turkey. Since
F38 is difficult to isolate, a serologic test specific
for F38 would aid in identifying the presence of
the organism in additional countries.
Several serologic tests detect serum
antibodies to F38. Routine use of these tests is
constrained by lack of equipment and trained
personnel. Recently, a latex agglutination test
(LAT) for field detection of goats with antibodies
to F38 polysaccharide was developed by SR-
CRSP scientists. The specificity of LAT was
further confirmed by evaluating specific growth
inhibiting rabbit antJiera to various Mycoplasma
isolates.
92
Nine hundred and fifty-four goat serum
samples from Mali were evaluated by the LAT
and 354 (37%) were positive. Since the LAT
detects antibodies to a F38 polysaccharide that
are not induced by other goat Mycoplasmas, it is
assumed that F38 infects goats in Mali.
Although confirmatioi, of the presence of
F38 requires isolation of the organism from
goats with CCPP, the LAT can be used to identify
herds in new countries where F38 isolation
is likely.
Publications
Thesis
Suryakant D. Waghela. A cloned DNA probe to
detect Cowdria ruminantiumin infected animals
and Amblyomma variegatumticks. Unpublished
Ph.D. thesis. Washington State University,
Pullman, Washington, 1989.
Publications in refereed journals
Shompole, S.P., Waghela, S.D., Rurangirwa, F.R.
and McGuire, T.C. 1989. Cloned DNA probes
identify Anaplasma ovis in goats and reveal a
high prevalence of infection. Journal of Clinical
Microbiology. 27:2730-2735. (Previously reported
as in press.)
Dilbeck, P.M., .Evciminnn, J.F., Crawford, T.B.,
Ward, A.C.S., Leathers, C.W., Holland, C.J.,
Mebus, C.A., Logan, LL., Rurangirwa, F.R. and
McGuire, T.C. 1990. Isolation of a previously
undescribed Rickettsia from an aborted bovine
fetus. Journal of Clinical Microbiology. 28:814­
816. (Previously reported as submitted for
review.)
Mwamachi, D.M., Rurangirwa, F.R., Musoke,
A.J. and McGuire, T.C. Immune colostrum
induces trypanotolerance in goat kids challenged
with Trypanosoma congolense. Acta
Tropica. (In press; previously reported as
submitted for review.)
Rurangirwa, F.R., McGuire, T.C., Mbai, L.,
Ndung'u, L and Wambugu, A. Preliminary
field test of lyophilised contagious caprine