1.Haemonchus contortus: parasite problem No. 1 from tropics - Polar Circle. Problems and prospects for control based on epidemiology.
J Waller Peter ; P Chandrawathani
Tropical biomedicine 2005;22(2):131-7
There is no doubt that on a global basis, Haemonchus contortus is by far the most important parasite of small ruminants (sheep and goats). This is particularly more so now, with the development of high levels of resistance to both the broad and narrow spectrum anthelmintic drugs in H. contortus throughout the world. Epidemiological studies describe the lower environmental limits for haemonchosis to occur in sheep, as being a mean monthly temperature of 18C and approximately 50mm rainfall. Thus it has been generally recognised that H. contortus is a problem parasite restricted to the warm, wet countries where sheep and goats are raised. However, recent evidence shows that this parasite is apparently common even in northern Europe. Thus the need for sustainable control strategies for H. contortus is becoming much more pressing. This report highlights two examples of sustainable and highly efficient control programmes for H. contortus, that can be implemented in regions at the extremes of its geographic range (Malaysia and Sweden), where the authors have had direct involvement.
Parasites
;
upper case aitch
;
control
;
Haemonchus contortus
;
Sheep
2.Comparative seroprevalences of bovine trypanosomiasis and anaplasmosis in five states of Malaysia
Wahab A. Rahman ; Samantha Fong ; Chandrawathani, P. ; Nurulaini, R. ; Zaini, C.M. ; Premalaatha, B.
Tropical Biomedicine 2012;29(1):65-70
Abstract. A comparative seroprevalence study on bovine trypanosomiasis and anaplasmosis was conducted. Sera of adult cattle and buffaloes of different breeds from farms from five different states in Malaysia were collected and tested for the presence of Trypanosoma evansi antibodies by CATT and Anaplasma marginale antibodies by c-ELISA. Of the 116 samples, 14.7% tested positive for bovine trypanosomiasis and 77.6% for bovine anaplasmosis.
3.Therapeutic use of Lucilia sericata maggot in controlling bacterial bio-burden in Rat wound model
Borkataki, S ; Katoch, R ; Goswami, P ; Bhat, A. ; Bhardwaj, H.R ; Chakraborty, D ; Chandrawathani, P
Tropical Biomedicine 2018;35(3):627-638
Delayed wound healing due to extraneous bacterial contamination, antibacterial resistance and other associated factors are of great concern in dealing patients having chronically infected wound. Medicinal properties of certain maggots of Calliphoridae family are known for its effective wound debridement therapy. The objective of the study was to evaluate the wound healing potential of maggots of Lucilia sericata in an experimentally infected cutaneous wound model in Wistar rat. The study was carried out by using male Wistar rats (n=48) by creating excisional wounds and later contaminated with mixed population of gram positive and gram-negative bacteria. Animals were divided randomly in to four groups with 12 individuals each, being denominated as control, antibiotic treated, maggot treated, and antibiotic plus maggot combination treated group. Ten pre-sterilized maggots were applied per centimetre square wound bed for 24 hours. Different wound kinetics in L. sericata maggot treated wounds revealed significant reduction in wound area with maximum contraction, early elimination of bacterial bioburden as compared to group of infected control and group of rats receiving only antibiotic treatment. The histopathological examination of wounded tissue of maggot treated groups showed early and better epithelialization, collagenation and neovascularization with complete healing of wound in two weeks. The maggot effects on healing when used singly or in combination with antibiotic were recorded to be similar. The results of the present study clearly demonstrate that the maggots of L. sericata possesses a definite antibacterial action along with removal of dead tissues and effectively reduced the bacterial bio-burden in infected wound and induced wound healing quickly.
4.Molecular Characterization of Avian Infectious Bronchitis Virus Isolated in Malaysia during 2014-2016
Leow, B.L. ; Syamsiah Aini, S ; Faizul Fikri, M.Y ; Muhammad Redzwan, S. ; Khoo, C.K ; Ong, G.H. ; Basirah, M.A ; Norazura, B. ; Mazaitul, Z. ; Mohd Khairil, A. ; Mohd. Jihan, R ; Sohayati, A.R ; Chandrawathani, P.
Tropical Biomedicine 2018;35(4):1092-1106
Avian Infectious Bronchitis (IB) is a highly contagious disease which can cause
huge economic losses to the poultry industry. Forty five IB viruses (IBV) were isolated
from poultry in Malaysia during 2014-2016. Phylogenetic analysis of the spike glycoprotein
1 (S1) gene revealed that all isolates were clustered into five distinct groups. The
predominant type of IBV isolated was QX strains (47%), second was 4/91 type (27%),
followed by Malaysian strain MH5365/95 (13%), Massachusetts type (11%) and finally
Taiwanese strains (2%). Four types of S1 protein cleavage recognition motifs were found
among the isolates which includes HRRRR, RRSRR, RRFRR and RRVRR. To our knowledge,
this is the first report describing the motif RRVRR and are unique to Malaysian strains. Six
IBVs were grouped in Malaysian MH5365/95 strains. Among these, one isolate was different
from others where it only shared 82% identity with MH5365/95 and to others. It formed its
own branch in the Malaysian cluster suggesting it may be a variant unique to Malaysia.
Alignment analysis of the S1 amino acid sequences indicated that point mutations, insertions
and deletions contribute to the divergence of IB variants. This study indicated at least five
groups of IBV are circulating in Malaysia with most of the isolates belonged to QX strains.
As new IBV variants continue to emerge, further study need to be carried out to determine
whether the current available vaccine is able to give protection against the circulating
virus.