An estimation of greenhouse gas emission from livestock in Bangladesh.

OBJECTIVES: The study was undertaken to investigate the greenhouse gas (GHG) emission from livestock in Bangladesh. MATERIALS AND METHODS: The GHG emission inventory of livestock in Bangladesh was estimated according to the tier 1 approach of the Intergovernmental Panel on Climate Change (IPCC) using livestock population data from 2005 to 2018. It was also extrapolated for the next three decades, according to the growth of the livestock population. RESULTS: According to the calculation, the GHG emission from livestock was 66,586 Gg/year CO2 equivalent (CO2e) in 2018. This emission may rise to 69,869, 80,618, 94,638, and 113,098 Gg/year CO2e in 2020, 2030, 2040, and 2050, respectively. The share of enteric methane, manure methane, direct nitrous oxide emission, and indirect nitrous oxide emission in the total GHG emissions represented 44.0%, 3.6%, 51.5%, and 0.9%, respectively, in 2018. It may arise at a rate of 1.54%-1.74% annually until 2050. CONCLUSION: The GHG inventory may guide professionals to formulate and undertake the effective mitigation measures of GHG emissions from livestock in Bangladesh. However, this inventory can be amended following the tier 2 approach recommended by the IPCC if necessary data are available at the national level.

Role of asymptomatic carriers and weather variables in persistent transmission of malaria in an endemic district of Assam, India.

BACKGROUND: Malaria transmission is perennial in the Assam-Arunachal Pradesh interstate border areas in the Sonitpur district of Assam, India. A yearlong study was carried out on the incidence of symptomatic and asymptomatic malaria and the role of asymptomatic malaria carriers in persistent transmission of the disease. The relationships between malaria incidence and weather parameters were also investigated. METHODS: Active and mass blood surveys were conducted on a monthly basis in Bengenajuli, Sapairaumari Pathar, and Nigam villages near the Assam-Arunachal Pradesh border. Epidemiological indices were estimated for malaria-positive cases. Multiple linear regression between monthly malaria incidence and monthly average temperature, and relative humidity along with monthly total rainfall was carried out. The known malaria vectors collected in CDC light traps were identified and recorded. RESULTS: Slide positivity rate (SPR) and Plasmodium falciparum percent (Pf%) for symptomatic malaria were 26.1 and 79.8, respectively. Prevalence of malaria vectors was observed throughout the year with varying density. Anopheles philippinensis/nivipes and A. annularis were predominant among the seven known vector species recorded currently. Asymptomatic parasitemia was detected throughout the year with SPR ranging from 4.8 to 5.3. Monthly rainfall with 1-month lag had the highest correlation (r=0.92) with SPR. The relationship between SPR and weather factors was established as SPR=-114.22+0.58 Tmin+1.38 RH+0.03 RF (R2=0.89; p=0.00). CONCLUSION: Low and relatively constant levels of asymptomatic parasitemia was present in the study area. High malaria vector density and presence of asymptomatic malaria parasite carriers were responsible for persistent malaria transmission in the region. This study concludes that passive detection and prompt treatment of asymptomatic carriers is essential for preventing persistent disease transmission. Rainfall along with some other weather variables may be used for predicting the malaria epidemics in the region. The predictive information could be useful to target resources more effectively.

Black fly (Simulium sp) composition, daytime biting activity and possible onchocerciasis infection in north-east, India.

Pupal stages of Simulium were collected and identified from various breeding habitats of twelve locations in northeastern India. Simulium flies, while attempting to land on human were collected between 07:00-17:00 hrs to understand the biting pattern. Seven species belonging to three sub-genera, Eusimulium (1), Gomphostilbia (1) and Simulium (5) belonging genus Simulium were encountered. Out of total seven species recorded, S. (E) aureohirtum, S. (G) tenuistylum and S. (S) rufibasis were predominant and shared 30.3%, 29.9% and 27.6% of total collection. Stream breeding habitat contributed 47.3% of total catch and was found to be preferred breeding habitat (p < 0.0001). S. (S) christophersi and S. (G) tenuistylum were recorded for the first time from the northeastern region of India. Simuliids biting rhythm showed bimodal pattern and were more active during sunny day (p < 0.0001). Microscopic dissection of simuliids (n = 266) did not incriminate simuliids as vector of onchocerciasis.

Growth performance and survival rate of Macrobrachium rosenbergii (De Man, 1979) larvae using different doses of probiotics.

The efficiency of probiotics (Ecomarine) in rearing of Macrobrachium rosenbergii larvae was evaluated in a commercial prawn hatchery for five weeks. Stage-1 (zero age) larvae (of length: 2 mm; weight: 0.12 mg) were stocked at the rate of 100 L(-1). The experiment determined the growth rate, survival rate of the larvae for the both treatment and control groups. Final average weight were found 8.39 ± 3.28E-04 and 8.18 ± 2.86E-04 mg and length were found 9.08 ± 0.649 and 9.02 ± 0.081 mm for treatment and control group respectively. Comparatively higher growth performance was observed in treatment than control. Post Larvae (PL) was first observed 20th days of culture in treatment tanks whereas PL in control tanks was found 24th days of culture. Survival rate was found 58 and 46% in treatment and control group respectively. There was significant (p < 0.05) survival rate between two experiment groups. This study revealed that probiotics could be better in quality seed production of M. rosenbergii while significant changes were not noticed in the physic-chemical parameters i.e., water temperature, salinity, DO, pH, nitrate-NO2, hardness and alkalinity observed in both the treatments.