Vol 27 No 2 December - The Indian Society for Parasitology

Journal of Parasitic Diseases
Vol. 27 (2) Dec. 2003, pp. 113-118
Distribution of trace metals in different proglottid regions of
Avitellina lahorea (Woodlands, 1927) and serum of sheep
V. VIJAYALAKSHMI*, K. RAMALINGAM & V. A. SATYAPREMA
P.G. & Research Department of Zoology, Govt. Arts College, Nandanam, Chennai-600 035,
Tamil Nadu, India
The distribution of trace metals in different proglottid regions of Avitellina lahorea (woodlands, 1927)
(anoplocephalid cestode) and serum of sheep host was determined by the use of an atomic absorption
spectrophotometer. The sodium content was found to be higher in the mature segments compared to both
immature and gravid segments. The electrolyte potassium level showed minimal concentrations in all the
three different regions. Calcium concentration showed consistent increase from immature to gravid regions.
The concentration of zinc, cobalt and selenium remained higher in the immature and mature regions when
compared to the gravid regions. Studies on selenium content in the parasite revealed that the parasitic
somatic tissue contained higher selenium levels than did the host somatic tissue.
Key Words : Avitellina lahorea; Proglottid; Trace metals.
INTRODUCTION
norganic elements play a significant role in the
Iphysiology, metabolism and immuno tolerance of
parasites. Thus an understanding about the trace metal
elements in the distribution of the host body and that of
the parasite is significant. It can give way to further
research to ascertain growth of the parasites by
elucidating specific mechanisms of poor or non
withdrawal of the essential elements without which the
parasite load will not persist in the host's body. m the
recent past there have been a few attempts to identify
and quantify certain inorganic elements in helminths
(Goodchild et al., (1962); Nadakal and Nair, 1982; Lal
and Kumar, 1985; Riggs et al., (1987); Pandey. and
Chowdhry, 1989 and Sures et al., 1997) or individual
elements in different groups of helminths (Chowdhury
and Singh, 1989, 1993 & 1995). Trace metals in broad
fish tapeworm Diphyllobothrium latum and blood of
carriers was analysed by Markkanen and Vuopala
(1965). Riggs et al. (1987) described elevated
selenium concentrations in the cestode
Bothriocephalus acheilognathi in comparison with the
tissues of two of its final host species. Certain
parasites, particularly cestodes of fish, can accumulate
* Corresponding Author
heavy metals at concentrations that are orders of
magnitude higher than those in the host tissues of the
environment (Sures et al., 1997).
Little information in available on the inorganic
composition of anoplocephalid parasites it was felt
+ +
that a quantitative study of Electrolytes (Na , K and
++
Ca ) and Trace elements (Co, Se and Zn) present in the
different proglottid regions adult A.lahorea would be
beneficial in supplementing other studies. In the
present report an attempt has been made to analyse the
probable role of certain elements during the
differentiation of proglottid regions of A.lahorea.
MA TERIALS AND METHODS
The tapeworms Avitellina lahorea (Woodland, 1927)
were collected from the intestine of naturally infected
sheep autopsied in the slaughterhouse at Chennai,
Tamil Nadu, India. The sheep intestines were
transported to the laboratory within half an hour of the
collection. In the laboratory each intestine was
carefully dissected and the tapeworms Were collected.
Then the worms were washed in distilled water to
render them free from intestinal contents and rinsed
quickly 3-4 times in normal saline. The immature,
mature and gravid proglottid region of the worm was
separated.