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One of the variables leading to the global spread of COVID-19 cases is the weather, which includes temperature and air quality. In this study, an investigation of the association between precipitation and COVID-19 cases was conducted to provide useful information on the possibility of this climate factor (precipitation) on the progression of COVID-19 cases for an appropriate management strategy. Secondary COVID-19 and rainfall data obtained from the Ministry of Health and the Meteorological Department in Malaysia were used for the study. The collected data were subjected to Pearson correlation analysis. The results of this study showed that both rainy days and rainfall amount were insignificant to COVID-19 cases, indicating that rainfall amount was not associated with COVID-19 transmission in Terengganu, Malaysia. Thus, this discovery could be used to inform individual and COVID-19 supervisors and the government as it prepares for the new weather season.

Field efficacy of anticoagulant rodenticides against rat infestation in oil palm plantation was carried out in a comparative study between five rodenticide baits. They were first-generation anticoagulant rodenticide baits, coumatetralyl, chlorophacinone and warfarin, and second-generation anticoagulant rodenticide baits, flocoumafen and brodifacoum. A control plot was left untreated for comparison purposes. In general, all treatments were effective to reduce the fresh rat damage on oil palm fresh fruit bunch (FFB) below the threshold level (5.0%) except for warfarin bait treatment. In the final round of baiting (5th round), the flocoumafen bait recorded the lowest fresh rat damage on FFB at 1.54 ± 0.14%. Coumatetralyl, chlorophacinone and brodifacoum recorded 2.95 ± 0.73%, 2.42 ± 0.57% and 4.30 ± 0.53% of fresh rat damage on FFB at the end of the study. The least effective was warfarin treatment which recorded 5.40 ± 0.18% in the final round of baiting. Only flocoumafen, coumatetralyl and chlorophacinone baits recorded more than 70.00% of rat damage reduction throughout the study as compared to pre-treatment. The brodifacoum treatment recorded rat damage reduction up to 58.70% and warfarin treatment was in the range of 13.58%-33.62%. All the rodenticide treatments managed to reduce the relative abundance of the estimated rat population in the field at the end of the study, except in the control plot.

The bagworm, Metisa plana Walker (Lepidoptera: Psychidae) is one of the major pests causes defoliation of oil palm leaves, resulting in severe yield loss of oil palm production. In this study, rhamnolipid, a biosurfactant produced by Pseudomonas aeruginosa USM-AR2, was tested for its effectiveness in causing mortality of bagworms. A total of 13 treatments were tested, namely mixtures of different doses of rhamnolipid and neem oil as well as cypermethrin, as chemical insecticides that are commonly used in oil palm plantations, to control bagworms. The results showed that the mixture of 200 ppm rhamnolipid and 30000 ppm neem oil, and a single treatment of 30000 ppm neem oil recorded 83.33% mortality at five days after treatment (DAT). The chemical insecticide treatment by cypermethrin recorded 100% mortality at 2 DAT. The lowest efficacy was observed on the mixture of 100 ppm rhamnolipid and 10000 ppm neem oil, producing 50% at 5 DAT and 73.33% of mortality at the end of the observation. Probit analyses showed that the LT50 score for single treatment of rhamnolipid of 100ppm and 200ppm were 5.22 DAT and 4.61 DAT. Meanwhile, the LT90 scores for 100ppm and 200ppm rhamnolipid were 13.08 DAT and 11.07 DAT respectively.

Five non-paired-translocated wild caught barn owl (Tyto alba javanica) transferred from Jerantut, Pahang in Peninsular to Lahad Datu in Sabah, Malaysia were tested for diet preference by size, and species and fecundity in captivity. Testing was done in flight cages where owls were free to select from a combination of three local rodent species distinguished into two size categories; large and small. Jacobs’ index confirmed that smaller rats were taken in greater numbers and took the shortest number of days to 100% consumption at Day 5 than larger ones. Preference for body parts consumed varied according to diet size and species. In the same period as the prey preference study, two females reproduced twice ranging from intervals of 44 to 63 days with an average clutch size of 6.8 eggs. Hatching rates ranged from 0% to 83% and fledging rates ranged from 0% to 75%. These results may have practical importance in the propagation of barn owls in their new environment as they will be exposed to different prey in terms of species and size range.

The toxicity and sub-lethal effects of two anticoagulant rodenticides; bromadiolone and chlorophacinone on barn owls, Tyto javanica were evaluated through aviary and field studies. In aviary study, T. alba showed behavioural aberrations less frequently took to flight and losing weight as early as on the fifth day after a meal of three rodenticide fed rats. Bromadiolone and chlorophacinone were found to have high degree of toxicity to T. alba. This finding is crucial since T. alba had been reported to consume up to three rats per night and this would certainly increase their potential exposure to secondary poisoning. HPLC analysis showed detection of residue in pellets regurgitated by T. alba can be used to indicate exposure of the latter to both compounds. However, blood residue method is limited to exposure duration of the compounds; the technique can only detect recent exposure to bromadiolone and chlorophacinone. The amounts of residue detected in the pellet samples for chlorophacinone were 69.9 to 81.6 μg/day or equivalent to 17.2 % to 27.4 % of the compound consumed and corresponding values for bromadiolone were 27.2 % to 34.5 % (72.24 – 85.77 μg/day). This suggests that the amounts of bromadiolone retained in the tissue of the rat were higher than chlorophacinone. Thus, a greater potential for secondary poisoning of bromadiolone than chlorophacinone can be deduced from this study. Field studies were conducted to evaluate the sub-lethal effects of bromadiolone and chlorophacinone on breeding performance, growth performance of nestling, thinning of eggshell and home range of T. alba in oil palm plantations. The breeding performances (clutch size, brood size and fledging success) of T. alba in rodenticides treated areas were lower in comparison to rodenticide free area. The lower reproductive performance was the consequence of secondary poisoning on T. alba. This is substantiated by the detection of high residues in the pellets collected in both the rodenticide t

The poten­tial sec­ondary haz­ards of two anti-coagulant roden­ti­cides com­monly used in Malaysian oil palm plan­ta­tions were eval­u­ated through feed­ing tri­als with cap­tive barn owls. A total of 12 adult barn owls (six pairs) were assigned to two roden­ti­cide treat­ments and a con­trol. The two treat­ments were rats fed with bro­ma­di­olone (0.005% a.i) and chloropha­ci­none (0.005% a.i) respec­tively. All roden­ti­cide treated owls received four poi­soned rats at Day 1, 3, 5 and 7 and a non-poisoned rat on each inter­ven­ing day for 30 days. Each barn owl of the con­trol group received a non-poisoned rat through­out the study. The reli­a­bil­ity of a non-invasive tech­nique such as an esti­ma­tion of anti-coagulant roden­ti­cide residue in regur­gi­tated pel­lets and blood sam­ples, were also eval­u­ated. Barn owls showed behav­ioural aber­ra­tions such as coarse breath­ing, fre­quent clos­ing of the eyes and reduced fly­ing activ­ity as early as Day 5 after con­sum­ing three poi­soned rats. The weight recorded at Day 7 after treat­ment showed that all treated owls reg­is­tered a reduc­tion in weight. The owls in the con­trol group on the con­trary gained weight. Bro­ma­di­olone and chloropha­ci­none were found to have high degree of tox­i­c­ity on cap­tive barn owls. After feed­ing the birds with as few as four poi­soned rats in a week the signs of tox­i­c­ity in birds such as haem­or­rhages (beak) and haematoma (wing) were found. This find­ing is very cru­cial since barn owls have been reported to con­sume up to three rats per night and this would cer­tainly increase their poten­tial expo­sure to lethal sec­ondary poi­son­ing. The detec­tion of residue in the pel­lets regur­gi­tated by barn owls can be used to indi­cate expo­sure of the lat­ter to both com­pounds. How­ever, as the blood residue method is lim­ited to the expo­sure dura­tion of the com­pounds, this tech­nique can only detect recent expo­sure to bro­ma­di­olone and chloropha­ci­none. The amou

This study investigated the effects of the first generation anticoagulant rodenticide chlorophacinone and the second generation rodenticide bromadiolone on the population and breeding performances of barn owls at oil palm plantations. Three treatment plots were established: one baited with chlorophacinone, one with bromadiolone, and the third kept rodenticide-free. Four rat-baiting campaigns which coincided with barn owl breeding season were carried in the rodenticide-treated plots. The occupancy rate of nest boxes, clutch size, brood size and fledging rates of the barn owls in each plot were monitored weekly throughout the study. Freshly regurgitated pellets from barn owls were collected from all occupied nest boxes at weekly intervals during the development of nestlings in each breeding season. The results show that the occupancy rate of the nest boxes was significantly higher in the rodenticide-free area compared with both rodenticide-treated areas. Similarly, the breeding performances, such as clutch size, brood size and fledging success, were higher in the rodenticide-free area compared with the rodenticide-treated areas. Results of high performance liquid chromatography (HPLC) analysis showed that 20.56% (mean residue: 1 .335 ± 0.073 lg/g) and 28.89% (mean residue: 0.777 ± 0.032 lg/g) of the collected regurgitated pellet samples from the rodenticide-treated areas contained bromadiolone and chlorophacinone residue, respectively. The mean brood size and fledging success of the barn owls showed a strong negative correlation with the mean concentration of rodenticide residues present in the regurgitated pellets and with the percentages of pellets detected having such residues (R2 k 0.44, P < 0.05). Similarly, the mean clutch size of barn owls was negatively correlated with the mean concentration of rodenticide residues and with the percentages of pellets detected with these residues. However, the correlation was not significantly different (R2 k 0.34, P > 0.05). I

In oil palm plantations chemical control is still the principal means of reducing pest numbers when their population levels are high. In this study, a series of field trials investigating the efficacy of several application techniques for insecticides against bagworm, Metisa plana, were carried out in oil palm plantations. The efficacy of the ground spraying technique for four insecticides (trichorfon, lambda cyahothrin, cypermethrin EC and cypermethrin EW) as well as a bio insecticide