1.Hexon and fiber gene changes in an attenuated fowl adenovirus isolate from Malaysia in embryonated chicken eggs and its infectivity in chickens
Norfitriah M SOHAIMI ; Mohd H BEJO ; Abdul R OMAR ; Aini IDERIS ; Nurulfiza M ISA
Journal of Veterinary Science 2018;19(6):759-770
Fowl adenovirus (FAdV) is distributed worldwide and causes economic losses in the poultry industry. The objectives of this study were to determine the hexon and fiber gene changes in an attenuated FAdV isolate from Malaysia in specific pathogen-free chicken embryonated eggs (SPF CEE) and its infectivity in commercial broiler chickens. SPF CEE were inoculated with 0.1 mL FAdV inoculum via the chorioallantoic membrane (CAM) for 20 consecutive passages. The isolate at passage 20 (E20), with a virus titer of 10(8.7)TCID₅₀/mL (TCID₅₀, 50% tissue culture infective dose), was inoculated (0.5 mL) into one-day-old commercial broiler chicks either via oral or intraperitoneal routes. The study demonstrated that 100% embryonic mortality was recorded from E2 to E20 with a delayed pattern at E17 onwards. The lesions were confined to the liver and CAM. Substitutions of amino acids in the L1 loop of hexon at positions 49 and 66, and in the knob of fiber at positions 318 and 322 were recorded in the E20 isolate. The isolate belongs to serotype 8b and is non-pathogenic to broiler chickens, but it is able to induce a FAdV antibody titer. It appears that molecular changes in the L1 loop of hexon and the knob of fiber are markers for FAdV infectivity.
Adenoviridae
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Amino Acids
;
Chickens
;
Chorioallantoic Membrane
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Eggs
;
Fowl adenovirus A
;
Liver
;
Malaysia
;
Mortality
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Ovum
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Poultry
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Serogroup
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Specific Pathogen-Free Organisms
;
Viral Load
2.Influence of citronella and chlorpyrifos on Chrysomya megacephala (Fabricius) and Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae) infesting rabbit carcasses
Denis, C.I. ; Nordin, N.H. ; Azman, A.R. ; Abdul Wahab, R. ; Ismail, D. ; Omar, B. ; Mahat, N.A.
Tropical Biomedicine 2018;35(3):755-768
Influence of citronella and chlorpyrifos on oviposition and duration for completing
life cycles for Chrysomya megacephala and Chrysomya rufifacies infesting decomposing
rabbit carcasses was studied. Male rabbit carcasses (n = 12) were equally divided into
control, citronella- and chlorpyrifos–treated groups, and left to decompose for 14 consecutive
days. C. megacephala was the first necrophagous fly oviposited in all control and citronellatreated
carcasses followed by C. rufifacies. Although initial oviposition of C. megacephala
was delayed (4-6 hours) in citronella-treated carcasses (P < 0.05), prolongation in completing
its life cycle was not observed. Neither delayed initial oviposition nor prolonged life cycle for
C. rufifacies in citronella-treated carcasses was observed. Oviposition was delayed for
chlorpyrifos-treated carcasses (0.42 g/L), and eclosion of eggs remained unsuccessful. The
findings deserve consideration because these chemicals are easily accessible and can be
used by cunning criminals to confuse forensic entomologists while estimating minimum postmortem
interval.