The mossy frogs of the genus Theloderma Tschudi comprise 28 described taxa (Sivongxay et al. 2016; Frost 2022), which are distributed from north-eastern India and Myanmar to southern China, across the peninsula of Indochina and Malaysia, to Indonesia (Poyarkov et al. 2015; Frost 2022). Theloderma albopunctatum is a small-sized taxon that is assigned to the T.-asperum species complex (Poyarkov et al. 2015, 2018; Sivongxay et al. 2016; Dever 2018). For long time, it has been believed to be a synonym of T. asperum. However, genetic analyses revealed that both taxa show significant differences. Currently, populations south of the Isthmus of Kra (southern Thailand, Malayan peninsular) are assigned to T. asperum, while populations north of it (southern China, northern and central Vietnam, adjacent Laos, south-eastern Cambodia) are assigned to T. albopunctatum. In addition, this species complex might contain further cryptic species (cf. Nguyen et al. 2015; Poyarkov et al. 2015) and according to Chunskul et al. (2021) four genetic groups do exist: group A comprises T. albopunctatum from southern and central Vietnam, Laos, central and north-eastern Thailand; group B is composed of populations from northern Vietnam and China; group C ranges from north-western Vietnam to northern Thailand and Myanmar; and group D is distributed in northern Vietnam (Thanh Hoa).
An account of two cases seen in Sarawak, both being Europeans and in bothAncylostoma caninum being responsible. Infection was acquired in a swampy part of the golf course which is frequented by pariah dogs heavily infected with this parasite. Many treatments proved unavailing, cure at length being obtained by rubbing oil of chenopodium into the track for ten minutes. Subsequently 1 part of this oil was mixed with 3 parts of castor oil, the mixture being applied in the same way. Whilst the one application to one area was sufficient, it took 10 to 14 days to work over both feet in each case
Hookworm-related cutaneous larva migrans (HrCLM) is a zoonosis which is endemic in many sub-tropic and tropical countries including Malaysia. We report a case of a 40-year old plantation worker who presented with a pruritic rash on his abdomen. It is important for clinicians to diagnose and treat HrCLM promptly as this condition results in considerable morbidity when treatment is delayed.
The levels of susceptibility of C. p. fatigans larvae from four different localities in Malaya to DDT, dieldrin, malathion, fenthion, diazinon and Sevin have been studied; their toxicity was: diazinon > fenthion > malathion > dieldrin > DDT > Sevin.Larvae from different localities showed a wide range of susceptibility to the chlorinated hydrocarbon insecticides, dieldrin (40x) and DDT (10x), but the organophosphorus compounds and the carbamate compound, Sevin, gave consistent results from all localities. One strain from a rural area (Lamir) was the most susceptible to all insecticides and has been used as a reference strain for related studies on the development of resistance.
Control of ticks and tick-borne pathogens is a priority for human and animal health. Livestock-holders extensively rely on acaricide applications for tick control. Different groups of acaricides including cypermethrin and amitraz have been consistently used in Pakistan. There has been a gap in understanding the susceptibility or resistance of Rhipicephalus microplus, the most prevalent tick in Pakistan, to acaricides. The present study aimed to molecularly characterize cypermethrin and amitraz targeted genes such as voltage-gated sodium channel (VGSC) and octopamine tyramine (OCT/Tyr) of R. microplus ticks in Khyber Pakhtunkhwa (KP), Pakistan to monitor the acaricides resistance. Tick specimens were collected from cattle and buffaloes in northern (Chitral, Shangla, Swat, Dir, and Buner), central (Peshawar, Mardan, Charsadda, Swabi, and Nowshera), and southern districts (Kohat, Karak, Lakki Marwat, Tank, and Dera Ismail Khan) of KP, Pakistan. Different concentrations of commercially available cypermethrin (10%) and amitraz (12.5%) were prepared for in vitro larval immersion tests (LIT). In LIT, the average mortality rate of immersed larvae was recorded that was increased gradually with an increase in the concentration of specific acaricide. The larvae's highest mortality rates (94.5% and 79.5%) were observed at 100-ppm of cypermethrin and amitraz, respectively. A subset of 82 R. microplus ticks was subjected to extract genomic DNA, followed by PCR to amplify partial fragments of VGSC (domain-II) and OCT/Tyr genes. The BLAST results of the consensus sequence of VGSC gene (domain-II) showed 100% identity with the acaricides susceptible tick sequence from the United States (reference sequence). Obtained identical sequences of OCT/Tyr genes showed maximum identity (94-100%) with the identical sequences reported from Australia (reference sequence), India, Brazil, Philippines, USA, South Africa, and China. Thirteen single nucleotide polymorphisms (10 synonymous and three non-synonymous) were observed at various positions of partial OCT/Tyr gene fragments. The SNP at position A-22-C (T-8-P) in OCT/Tyr gene has been linked to amitraz resistance in R. microplus ticks. Molecular analysis and LIT bioassay's findings indicate the availability of resistant R. microplus ticks in the KP region. To our understanding, this is the first preliminary study to monitor cypermethrin and amitraz resistance via molecular profiling of cypermethrin and amitraz targeted genes (VGSC and OCT/Tyr) in combination with in vitro bioassays (LIT) in R. microplus ticks from Pakistan.
The fall armyworm (Spodoptera frugiperda) is a major economic pest in the United States and has recently become a significant concern in African and Asian countries. Due to its increased resistance to current management strategies, including pesticides and transgenic corn, alternative management techniques have become more necessary. Currently, silicon (Si) is being used in many pest control systems due to its ability to increase plant resistance to biotic and abiotic factors and promote plant growth. The current experiments were carried out at the College of Plant Protection, Gansu Agricultural University, Lanzhou, China, to test the effect of Si on lifetable parameters and lipase activity of fall armyworm and vegetative and physiological parameters of maize plants. Two sources of Si (silicon dioxide: SiO2 and potassium silicate: K2SiO3) were applied on maize plants with two application methods (foliar application and soil drenching). The experiment results revealed that foliar applications of SiO2 and K2SiO3 significantly (P≤0.05) increased mortality percentage and developmental period and decreased larval and pupal biomass of fall armyworm. Similarly, both Si sources significantly (P≤0.05) reduced lipase activity of larvae, and fecundity of adults, whereas prolonged longevity of adults. Among plant parameters, a significant increase in fresh and dry weight of shoot, stem length, chlorophyll content, and antioxidant activity was observed with foliar applications of Si. Root fresh and dry weight was significantly (P ≤ 0.05) higher in plants treated with soil drenching of SiO2 and K2SiO3. Moreover, SiO2 performed better for all parameters as compared to K2SiO3 and control treatment. The study conclusively demonstrated a significant negative effect on various biological parameters of fall armyworm when plants were treated with Si, so it can be a promising strategy to control this pest.
This study was conducted to clarify the development of free neuromasts with growth of the barramundi, Lates calcarifer. A pair of free neuromasts was observed behind the unpigmented eyes in newly hatched eleutheroembryos with a mean total length of 1.93 mm, and two-hour-old eleuthero-embryos could respond to an approaching pipette. At 2 days after hatching, the egg yolk sac was mostly consumed, the eyes were pigmented, and the larvae commenced feeding on rotifers. Free neuromasts increased in number with growth and commenced developing into canal neuromasts in barramundi 15 days old with a mean total length of 8.07 mm. The average length of the major axis of the trunk free neuromasts attained approximately 12.9-15.5 microm, and the number of sensory cells was 15.4-17.5 at 15-20 days old. Developed cupulae of free neuromasts were observed in 1-day-old eleutheroembryos. The direction of maximum sensitivity of free neuromasts, determined from the polarity of the sensory cells, coincided with the minor axis of the lozenge-shaped outline of the apical surface of the free neuromasts. The polarity of trunk neuromasts was usually oriented along the antero-posterior axis of the fish body, but a few had a dorso-ventral direction. On the head, free neuromasts were oriented on lines tangential to concentric circles around the eye.
Entomologi forensik dapat ditakrifkan sebagai pengetahuan mengenai serangga yang berkait rapat dengan bangkai terutamanya manusia, dengan tujuan ia dapat digunakan dalam penentuan jangka masa pascakematian. Jangka masa pascakematian (PMI) dapat ditentukan dengan mengambil kira spesies serangga dan peringkat perkembangan setiap spesies tersebut. Oleh kerana penentuan jenis spesies memerlukan serangga berkembang ke peringkat dewasa dan ini mengambil masa yang lama, maka objektif utama kajian ini adalah untuk mengoptimumkan suhu dan kelembapan terhadap perkembangan serangga dengan menggunakan larva Chrysomya megacephala sebagai spesimen. Larva C. megacephala dipindahkan ke dalam bekas khas, kemudiannya dimasukkan ke dalam pengeram yang telah dilaraskan suhunya kepada 27, 30, 33, 36 dan 39°C. Selepas menentukan suhu optimum perkembangan larva, aras kelembapan relatif ditentukan. Ini dilakukan dengan menentukan tempoh masa yang diperlukan untuk mengembangkan telur C. megacephala hingga ke peringkat dewasa. Untuk itu aras kelembapan relatif dalam pengeram tersebut dilaraskan kepada 54.2, 57.6, 76.0 dan 67.5% (kawalan). Peringkat perkembangan C. megacephala direkodkan. Hasil yang diperolehi menunjukkan perkembangan C. megacephala lebih pantas pada suhu 33oC berbanding suhu-suhu lain yang digunakan. Aras kelembapan relatif yang optimum juga telah dikenal pasti iaitu pada 76.0%. Dengan menggunakan keduadua data didapati keseluruhan peringkat perkembangan C. megacephala iaitu daripada peringkat telur hingga dewasa dapat dipendekkan daripada 8 hingga 9 hari kepada 5 hari.
Perkembangan penggunaan insektisid sebatian organostanum(IV) terhadap Aedes aegypti telah diterokai dan diuji keberkesanannya bagi mengatasi masalah kerintangan insektisid sedia ada. Kajian ini dijalankan bertujuan menguji kesan insektisidal iaitu larvisidal dan adultisidal dua siri baru sebatian difenilstanum(IV) dan trifenilstanum(IV) alkilfenilditiokarbamat ke atas Ae. aegypti di makmal. Keempat-empat sebatian iaitu difenilstanum(IV) etilfenilditiokarbamat (DFEF), trifenilstanum(IV) etilfenilditiokarbamat (TFEF), difenilstanum(IV) butilfenilditiokarbamat (DFBF) dan trifenilstanum(IV) butilfenilditiokarbamat (TFBF) telah dijalankan ujian bioasai larvisidal ke atas larva instar ketiga Aedes aegypti. Kajian lanjutan diteruskan bagi sebatian yang telah menunjukkan aktiviti larvisidal terbaik untuk menguji kesan adultisidnya ke atas nyamuk betina Aedes aegypti. Hasil ujian bioasai larvisidal, didapati sebatian TFEF menunjukkan kesan larvisidal terbaik dengan nilai LC50 dan LC90 pada 0.082 ppm dan 0.184 ppm masing-masing. Sementara itu, sebatian TFBF juga menunjukkan kesan larvisidal yang baik dengan nilai LC50 dan LC90 masing-masing pada 0.108 ppm dan 0.273 ppm manakala kedua-dua sebatian DFEF dan DFBF didapati tidak menunjukkan kesan larvisidal yang baik. Ujian adultisidal pula, sebatian TFEF didapati tidak menunjukkan kesan adultisidal yang baik dengan nilai LC50 dan LC90 masing-masing yang agak tinggi iaitu 31,556.03 ppm dan 98,427.05 ppm. Walaupun sebatian TFEF didapati tidak menunjukkan kesan adultisid yang baik, ianya sangat berpotensi untuk dibangunkan sebagai larvisid. Namun begitu, kajian lanjutan perlu dilakukan untuk menjelaskan dan memastikan sebatian ini selamat digunakan sebagai larvisid.