scholarly journals Oviposition of Aedes aegypti and Aedes albopictus on Ovitraps in Dry and Rainy Seasons in Southern Vietnam

2021 ◽  
Vol 37 (3) ◽  
pp. 169-171
Author(s):  
Takashi Tsunoda ◽  
Huynh Thi Thuy Trang ◽  
La Hoang Huy ◽  
Le Nguyen Thuy Duy ◽  
Pham Thi Thuy Ngoc ◽  
...  

ABSTRACT Ovitraps were set inside and outside of 15 households in December 2012 (dry season) and August 2013 (rainy season) in 2 communes (An Thanh and Phu Hoa) of Binh Duong Province in southern Vietnam. Eggs laid in the ovitraps were collected after 4 days, dried, and soaked in water. Hatched larvae were transferred to cups and reared to adulthood to identify the species. The rate of positive ovitraps did not differ between December and August for Aedes aegypti, but it was lower in December for Ae. albopictus. The number of eggs laid per ovitrap by Ae. aegypti did not differ between December and August, while that for Ae. albopictus decreased significantly in December in both communes. Moreover, Ae. albopictus laid eggs in ovitraps placed outside the households. Therefore, it is necessary for future studies to investigate whether the major source containers for oviposition had dried in the dry season or Ae. albopictus entered diapause, leading to these observations.

Insects ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 58
Author(s):  
Carlos F. Marina ◽  
J. Guillermo Bond ◽  
Kenia Hernández-Arriaga ◽  
Javier Valle ◽  
Armando Ulloa ◽  
...  

Indoor and outdoor ovitraps were placed in 15 randomly selected houses in two rural villages in Chiapas, southern Mexico. In addition, ovitraps were placed in five transects surrounding each village, with three traps per transect, one at the edge, one at 50 m, and another at 100 m from the edge of the village. All traps were inspected weekly. A transect with eight traps along a road between the two villages was also included. Population fluctuations of Aedes aegypti and Ae. albopictus were examined during 2016–2018 by counting egg numbers. A higher number of Aedes spp. eggs was recorded at Hidalgo village with 257,712 eggs (60.9%), of which 58.1% were present in outdoor ovitraps and 41.9% in indoor ovitraps, compared with 165,623 eggs (39.1%) collected in the village of Río Florido, 49.0% in outdoor and 51.0% in indoor ovitraps. A total of 84,047 eggs was collected from ovitraps placed along transects around Río Florido, compared to 67,542 eggs recorded from transects around Hidalgo. Fluctuations in egg counts were associated with annual variation in precipitation, with 2.3 to 3.2-fold more eggs collected from ovitraps placed in houses and 4.8 to 5.1-fold more eggs in ovitraps from the surrounding transects during the rainy season than in the dry season, respectively. Aedes aegypti was the dominant species during the dry season and at the start of the rainy season in both villages. Aedes albopictus populations were lower for most of the dry season, but increased during the rainy season and predominated at the end of the rainy season in both villages. Aedes albopictus was also the dominant species in the zones surrounding both villages. The numbers of eggs collected from intradomiciliary ovitraps were strongly correlated with the numbers of eggs in peridomiciliary ovitraps in both Río Florido (R2adj = 0.92) and Hidalgo (R2adj = 0.94), suggesting that peridomiciliary sampling could provide an accurate estimate of intradomiciliary oviposition by Aedes spp. in future studies in these villages. We conclude that the feasibility of sterile insect technique (SIT)-based program of vector control could be evaluated in the isolated Ae. aegypti populations in the rural villages of our baseline study.


2018 ◽  
Vol 4 (2) ◽  
Author(s):  
Sardjito Eko Windarso dkk

The increasing of malaria cases in recent years at Kecamatan Kalibawang has been suspected correspond with the conversion of farming land-use which initiated in 1993. Four years after the natural vegetation in this area were changed become cocoa and coffee commercial farming estates, the number of malaria cases in 1997 rose more than six times, and in 2000 it reached 6085. This study were aimed to observe whether there were any differences in density and diversity of Anopheles as malaria vector between the cocoa and mix farming during dry and rainy seasons. The results of the study are useful for considering the appropriate methods, times and places for mosquito vector controlling. The study activities comprised of collecting Anopheles as well as identifying the species to determine the density and diversity of the malaria vector. Both activities were held four weeks in dry season and four weeks in rainy season. The mea-surement of physical factors such as temperature, humidity and rainfall were also conducted to support the study results. Four dusuns which meet the criteria and had the highest malaria cases were selected as study location. Descriptively, the results shows that the number of collected Anopheles in cocoa farming were higher compared with those in mix horticultural farming; and the number of Anopheles species identifi ed in cocoa farming were also more varied than those in the mix horticultural farming.Key words: bionomik vektor malaria, anopheles,


Atmosphere ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1622
Author(s):  
Alcindo Mariano Souza ◽  
Cláudio Moisés Santos e Silva ◽  
Bergson Guedes Bezerra

The caatinga is considered South America’s largest seasonally dry tropical forest (SDTF) and one of the most vulnerable endemic biomes in relation to climate change. The surface albedo in caatinga is relevant to understanding the role of this biome in the climate of the Northeast region of Brazil. Thus, a comparative analysis was conducted between the albedos of preserved and anthropized caatinga (pasture). Data were collected using CNR4-type net radiometers during the dry and rainy seasons. The mean albedo values were higher in the Pasture both in the dry and rainy season, with values of 0.181 and 0.177, respectively. In the caatinga, the mean albedo values were 0.137 in the dry season and 0.146 in the rainy season. The hourly average values for albedo, taken between 6:30 a.m. and 4 p.m., with intervals of 30 min, were also higher in the pasture. For convenience, this study uses local standard time (LST), which is 3 h behind from coordinated universal time (UTC). The greatest dispersions in the frequencies of the mean hourly albedo values occurred in the early morning and late afternoon. Some of the consequences of this study is the confirmation that there is an increase in albedo in caatinga replaced by pasture and this causes a reduction in the net radiation and also the finding that a region where there is adequate pasture management also enables albedo management and from solar radiation. And that further studies can indicate the impacts on temperature and precipitation, especially in warmer periods during the dry season.


2017 ◽  
Vol 38 (6) ◽  
pp. 3657
Author(s):  
Luana de Fátima Damasceno dos Santos ◽  
Edgard Cavalcanti Pimenta Filho ◽  
Edilson Paes Saraiva ◽  
Dermeval Araújo Furtado ◽  
Walter Esfrain Pereira ◽  
...  

This study aimed to evaluate the sexual behavior of 'Morada Nova' breeding sheep reared in the Brazilian semi-arid during dry and rainy seasons in a semi-intensive system. The behavioral data were gathered from 4 rams and 114 ewes, among which 55 during the rainy season and the other 59 females in the dry season. The behavioral observations were conducted from 6 am to 5 pm, during both periods. The observations were carried out continuously and split into 'event' (execution frequency) and 'state' (execution time). During the rainy season, the breeding sheep showed the most efficient sexual behavior, with a shorter reaction time (RT) and less frequent mount attempts (MA), being of 122 sec and 2.97, respectively. However, throughout the dry period, some sexual behaviors such as sniffing the urogenital of females (SUF), penis exposure (EXP), head tossing (HT), and courting of females (FC) became more frequent, mainly in the afternoon, as with the flehmen response (FR). Male courting behavior was more evident in the rainy season during the end of the day, remaining less active during the dry period. Sexual behavior intensity in 'Morada Nova' sheep varies throughout the day, especially in the dry season.


2020 ◽  
Author(s):  
Joannitta Joannides ◽  
Mawuli Dzodzomenyo ◽  
Faustus Azerigyik ◽  
Eudocia Esinam Agbosu ◽  
Deborah Pratt ◽  
...  

AbstractAedes-borne viral diseases mainly Yellow Fever (YF), Dengue (DEN), Zika (ZIK) and Chikungunya (CHK) have contributed to many deaths’ in the world especially in Africa. There have been major outbreaks of these diseases in West Africa. YF outbreaks have occurred in Ghana. Although Ghana has not recorded any outbreak of DEN, ZIK and CHK, the risk is high due to its proximity to West African countries where outbreaks have been recently been recorded. This study assessed the risk of transmission of Yellow fever (YFV), Dengue (DENV), Chikungunya (CHKV) and Zika (ZIKV) viruses in Larabanga and Mole Game Reserve areas in Northern Ghana. The immature and adult stages of Aedes mosquitoes were collected from Larabanga and Mole Game Reserve area. There was a significant (P>0.001) number of mosquitoes collected during the rainy season than the dry season. A total of 1,930 Aedes mosquitoes were collected during the rainy season and morphologically identified. Of these, 1,915 (99.22%) were Aedes aegypti and 15 (0.22%) were Aedes vittatus. During the dry season, 27 Aedes aegypti mosquitoes were collected. A total of 415 Ae. aegypti mosquitoes were molecularly identified to subspecies level of which Aedes (Ae) aegypti aegypti was the predominant subspecies. Both Ae. aegypti aegypti and Ae aegypti formosus exist in sympatry in the area. All Aedes pools (75) were negative for DENV, ZIKV and CHKV when examined by RT-PCR. Three Larval indices namely House Index, HI (percentage of houses positive for Aedes larvae or pupae), Container Index, CI (the percentage of containers positive for Aedes larvae or pupae) and Breteau Index, BI (the number of positive containers (with larvae and/or pupae per 100 inspected houses) were assessed as a measure for risk of transmission. The HI, CI and BI for both sites were as follows; Mole game reserve (HI, 42.1%, CI, 23.5% and BI, 100 for rainy season and 0 for all indices for dry season) and Larabanga (39%, 15.5% and 61 for rainy season and 2.3%, 1.3% and 2.3 for dry season). The spatial distribution of Aedes breeding sites in both areas indicated that Aedes larvae were breeding in areas with close proximity to humans. Lorry tires were the main source of Aedes larvae in all the study areas. Information about the species composition and the potential role of Aedes mosquitoes in future outbreaks of the diseases that they transmit is needed to design efficient surveillance and vector control tools.


2021 ◽  
Vol 6 ◽  
pp. 41-46
Author(s):  
E. C. I. Molokwu ◽  
N. N. Umunna ◽  
S. M. Dennis

THE effect of bone meal supplementation on pregnancy and plasma phosphorus level in White Fulani (Bunaji) cattle was investigated over a 13-month period. The monthly mean plasma levels of inorganic phosphorus for supplemented Cows varied from 4.63mg/100ml in dry season to 8.09mg/100ml in the rainy season in contrast to 3.07 to 7.09/100ml in the dry and rainy seasons respectively, for the controls. Bonemeal supplementation resulted in earlier conception and calving. Fifty percent of the supplemented cows calved by the end of the period of supplementation in contrast to 25 percent of the controls. By two months after the study period, 100% of cows that received the supplementation had conceived compared with 87.50% of the controls. It is concluded from the study that bonemeal is a practical method for improving the fertility of White Fulani cattle in the grazing areas of Nigeria where soil and forage are deficient in phosphorus 


2021 ◽  
Vol 24 (2) ◽  
pp. 192-196
Author(s):  
P. D Halle ◽  
M. A. Raji ◽  
N. D. G. Ibrahim

A ten-year (1986 - 1995) record of necropsy report on diagnosed livestock diseases in Zaria, Kaduna State is evaluated to determine the prevalence and seasonal occurrence of the major livestock diseases in the Northern part of Nigeria. A total 1093 animals comprising 132 cattle, 240 goat 318 shell, 20 horses, 47 pigs and 336dogs were examined at necropsy. Some diseases such as cowdriosis, Pneumonia, Ectoparasitism, and Haemonchosis showed seasonal fluctuation while others like Babesiosis, Trypanosomiasis and physical injuries were evenly distributed throughout the year. The major problem of livestock in Zaria was Pneunonia (247 cases) with a seasonal occurrence of 38.6% and 61.31% for the dry and rainy seasons respectively. During the rainy season, cowdriosis (17.42%) in cattle, Pneumonia (25.0%, 21.10% and 20.0%) in goats, sheep and horses; gastroenteritis (14.89%) and starvation/malnutrition (14.89%) in pigs and rabies (8.93%) in dogs were the major problems. Starvation/malnutrition (4.17%) in Goats and gastroenteritis (12.5%) were more prevalent during the dry season. The relevance during of this report to effective control measures for the livestock resources in Nigeria is also highlighted.


2020 ◽  
Vol 21 (2) ◽  
pp. 219-226
Author(s):  
Sumaryati Sumaryati ◽  
Asri Indrawati ◽  
Dyah Aries Tanti

ABSTRACTBig cities with valley or basin topography such as Bandung, generally have problems with air pollution due to the inversion layer and photochemical smog formations. The inversion conditions cause photochemical smog settling so that the air looks dark on the surface. This study was conducted to analyze the character of inversion events in Bandung due to vertical temperature changes. The inversion layer is obtained from the TAPM (The Air Pollution Model) model and in situ measurement of vertical temperatures by flying a temperature sensor to get the temperature profile. The TAPM running model is carried out in July and December following the dry and rainy seasons. In situ temperature observations are carried out in September 2018 using a drone according to the dry season and data corresponding to the rainy season using data from previous research with a radiosonde balloon. The running model results show that the inversion layer in the rainy season is stronger and more persistent than in the dry season. The inversion layer at night until morning occurs at the surface level, then the inversion layer rises, and finally, the inversion layer breaks up around 10:00 in July and around 12:00 in December. Validation with in situ measurements shows similarity in the pattern. The inversion event correlates with the subsidence and dilution of smog and photochemical smog pollutants from the edge of the Bandung Basin area.Keywords: basin, urban, photochemical smog, inversionABSTRAKKota besar dengan topografi berbentuk lembah atau cekungan seperti Bandung, umumnya memiliki masalah dengan polusi udara karena adanya pembentukkan lapisan inversi dan smog fotokimia. Kondisi inversi menyebabkan terjadinya pengendapan smog fotokimia, sehingga udara terlihat gelap pada permukaan. Penelitian ini dilakukan untuk menganalisis karakter kejadian inversi di Cekungan Bandung akibat dari perubahan temperatur vertikal. Lapisan inversi diperoleh dari model TAPM (Model Polusi Udara) dan pengukuran in situ temperatur vertikal dengan menerbangkan sensor suhu untuk mendapatkan profil suhu. Running model TAPM dilakukan pada bulan Juli dan bulan Desember berkesesuaian dengan musim kemarau dan hujan, sedangkan pengamatan temperatur in situ dilakukan pada bulan September 2018 dengan menggunakan wahana drone yang berkesesuaian dengan musim kemarau, serta untuk data yang berkesesuaian dengan musim hujan menggunakan data hasil penelitian sebelumnya dengan wahana balon radiosonde. Hasil running model menunjukkan, lapisan inversi pada musim hujan lebih kuat dan lebih persisten dari pada musim kemarau. Lapisan inversi pada malam sampai pagi hari terjadi pada level permukaan, kemudian lapisan inversi ini naik dan akhirnya lapisan inversi pecah sekitar pukul 10:00 pada bulan Juli dan sekitar pukul 12:00 pada bulan Desember. Validasi dengan pengukuran in situ menunjukkan kemiripan pola. Kejadian inversi berkorelasi dengan pengendapan dan pengenceran polutan smog dan smog fotokimia dari pinggir Cekungan Bandung. Kata kunci: cekungan, urban, smog fotokimia, inversi


Author(s):  
B.M. Neves ◽  
E.J.B. Lima ◽  
C.D. Pérez

The present work records for the first time the association between ophiuroids and the octocoral Carijoa riisei. Carijoa riisei is a colonial octocoral very abundant in the littoral of Pernambuco (Brazil), with growth by creeping stolons with an arborescent structure creating an optimal environment for epibionts. The objectives of the work were to identify the species of Ophiuroidea associated with C. riisei, and to verify the existence of seasonality through the density, abundance and frequency of sampled taxa. Due to the known relationship between the ophiuroids and sponges related in the literature, the sponges founded associated with C. riisei were recorded. Seasonal samples of the beaches of Porto de Galinhas and Guadalupe were realized. In Guadalupe, 39 and 21 ophiuroids (dry and rainy seasons respectively) belonging to the families Ophiactidae (Ophiactis savignyi, Ophiactis lymani) and Ophiotrichidae (Ophiotrhix angulata) were identified. Ophiactis savignyi stood out in all the analysed stations (48.72% in dry season and 52.38% in rainy season). The average density of the ophiuroids was 10.74 ind/100 g of C. riisei, varying from 12.56 ind/100 g in the dry season to 8.92 ind/100 g, in the rainy season. Amongst the species of ophiuroids recorded in the samples, O. savignyi showed 80% and 100% frequency of occurrence in the dry and the rainy seasons, respectively, and O. lymani showed 80% during the dry season. The presence of O. lymani in Guadalupe constitutes the first record in Pernambuco state. Taking into account that all the ophiuroids collected in Guadalupe were considered juveniles (1–3 mm of disc diameter), the microhabitat created by C. riisei may be utilized as a recruitment place for some ophiuroids. No ophiuroids were found at Porto de Galinhas beach, just as for sponges. On the other hand, the ophiuroids were always found with sponges in Guadalupe beach. For this reason, the ecological relation of the ophiuroids with C. riisei could be observed as an occasional relation, in the way that the octocoral supplies a support structure to the growth of the many sponges that have given a favourable habitat to shelter ophiuroids.


2020 ◽  
Vol 147 ◽  
pp. 02020
Author(s):  
Ratih Ida Adharini ◽  
Namastra Probosunu ◽  
Atika Arifati ◽  
Tika Drastiana ◽  
Fitriana C. Rusnasari

The intertidal zone is a transition area between sea and land with unique characteristics. This research aimed to determine the diversity and types of fish in the intertidal zone of Sundak Beach, Yogyakarta, Indonesia. This research was conducted in December 2016–September 2017 along the intertidal zone of Sundak Beach. Fish samples were collected by fishermen twice a month using a hand net and hand line in an area of 22,000 m2 by random sampling. Water quality data included air and water temperatures, pH, salinity, tides, rainfall intensity, and substratum. Fish samples were identified, and the total length and weight were measured. Results showed that carnivores and herbivores were dominant during the rainy season, whereas carnivores and omnivores were dominant during the dry season. Total of 179 fish, which were grouped into 18 families and 31 species. The diversity species index was 1.067 (intermediate diversity) during the rainy season but 0.19 (low diversity) during the dry season. The dominancy index was low (0.11–0.34) during the dry season, whereas during the rainy season was higher (0.18–0.72). The study concluded that the intertidal zone of Sundak Beach has a good condition as nursery, feeding, and spawning grounds for fishes.


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