Diversity of rodents and shrews in Tanzania and prevalence of their parasites: a case study of Zaraninge Coastal Forest and Gongo Village
Loading...
Date
2024-05
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Sokoine University of Agriculture
Abstract
Rodents are important in the ecology of mammals because they
serve as predators, prey, pests, and grazers. Their composition,
community structure, population density, and habitat utilization are
linked to environmental variables like resource availability and
biological interactions. In Zaraninge Coastal Forest, several studies
on rodents and shrews were undertaken before and after it the
Coastal Forest was incorporated to the Saadani National Park
(SANAPA). However, these studies focused on distribution and
diversity of specific species of mammals in the Coastal Forest. The
studies reported that human encroachment in the Coastal forest as
one of threats affecting the forest. Nonetheless, information on the
diversity of rodents and shrews and their parasites after annexing
the forest to the National park to enhance its protection was not
availed. Thus, there is a knowledge gap on the parasites of rodents
and shrews, given that the rodents and shrews are reservoirs of
parasites that can be potential agents of transmitting diseases to
human beings. So, it was crucial to investigate the diversity of
rodents and shrews, but also investigate the parasites hosted in
rodents and shrews that can transmit zoonotic diseases to human
beings. The findings from the study aimed to provide information on
the diversity of rodents and shrews, but also information of their
parasites of health importance as most outbreaks of rodent-borne
diseases in humans are commonly related to socio-economic
deficiencies. The study was carried out from May to October 2021.
The removal method using two types of traps –Sherman and
Havahart was used to collect rodents and shrews. For ectoparasites,
fur of the captured individuals were combed to dislodge
ectoparasites, and for hemoparasites, blood samples were collected
from a supra orbital vein and blood was smeared on glass slide to
make smears. In analysis the Paleontological Statistics (PAST)
Program version (3.22) and Microsoft Excel (2007) were used to
analyze the data, which determined the diversity and relative
abundance of rodents and shrews. The prevalence of parasites in he captured individuals was also investigated using the prevalence
formula in the study. The Chi-square test was employed to
investigate the link between the ectoparasites infestation and the
individuals' sexes. About 203 individuals were caught in this study,
where 197 individuals were rodents (Mastomys natalensis,
Gramomys dolichurus, Gerbilliscus leucogaster, Lemniscomys
rosalia, Cricetomys spp, Beamys hindei, Graphiurus murinus and
Xerus rutilus) and 7 individuals were the non-rodentia (Crocidura
hirta, Petrodromus tetradactylus and Galago spp. The study findings
revealed that the rodents’ diversity value was higher in the Coastal
Forest, than in the Gongo Fallow Lands. The diversity of rodents in
Zaraninge Coastal Forest obtained was 1.49 and that of Gongo
Fallow Land was 0.22, yet, there were no any statistically difference
on the diversity of the two sites. Meanwhile, the shrew diversity
appeared to be similar on both sites (0.6931). The trap success
(abundances) for rodents ranged from 4.60% to 0.03%, while for the
shrews ranged from 0.08% to 0.05%. The infestation of
ectoparasites to rodents and shrews, was higher (92.2%) in the
fallow lands of Gongo Village than in the Coastal forest which had
7.8%. However, the infection rate of hemoparasites to rodents and
shrews was also higher (95.1%) in the fallow lands than in the
Coastal forest (4.9%). There was no significant association of the
parasites infection and infestation to the sexes of the individuals
caught. Yet, the count of the ectoparasites was higher on the female
rodents and shrews (1035) than that of the male rodents and shrews
(1026). In this study, the ectoparasites obtained were the
Echinolaelaps echidninus, Boophilus spp, Xenopyslla brasiliensis
and Polyplax stephensi. E. echidninus had higher prevalence of
942.6% on rodents particularly on Mastomys natalensis while the
lower prevalence was seen in P. stephensi. In shrews, Boophilus
spp had the highest prevalence of 233.3% than other ectoparasites.
On the account of hemoparasites, Plasmodium sp had higher
prevalence of 59.8% while Bacillus sp had lower prevalence of
0.5%.Therefore, these findings raises a concern on the public health
of the nearby community, livestock and the wildlife since their interaction is inevitable. The parasites found in this study are of
zoonotic importance, hence it’s important to put emphasis on the
hygiene of the people and the environment so as to avoid any
eruption of the zoonotic diseases in the community. The findings on
diversity provide the information on the importance of the
conservation on habitats in order to preserve species. However,
higher captures on fallow lands alerts the community on developing
pests control strategies to protect their farms and houses from been
invaded by rodents. Further studies on rodents and shrews of peri-
domestic and domestic areas, reports on zoonotic diseases that
maybe found in the nearby community, development of strategies to
prevent rodents as destructive pest in farms are recommended so
as to get more detailed information on the rodents and shrews in
these areas
Description
MSc Dissertation
Keywords
Rodents, shrews, parasites, diversity, abundance, Zaraninge Coastal Forest