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The stinging catfish, Heteropneustes fossilis (Bloch, 1974) is a commercially important fish species in Asia. This is an important food fish as is enriched with high amounts of protein, iron and calcium. The current research demonstrates the population structure, size at sexual maturity, spawning- and peak-spawning season and fecundity of H. fossilis in an important wetland ecosystem - Gajner Beel in northwestern Bangladesh with an aim of its sustainable conservation through induced breeding and aquaculture practices. A total of 426 stinging catfish captured from the Gajner Beel through monthly sampling from January to December 2019 used in the study. Total length (TL), standard length (SL) and body weight (BW) of individual fishes were measured. The size ranges were with 6.70–24.10 cm TL, 1.37–83.94 g BW. Gonads were removed carefully through ventral dissection and weighted. Lm was 14.02, 13.5, 13.0 and 15.0 cm based on maximum length (Lmax), TL vs. GSI (%), TL vs. SL and logistic model, respectively. Monthly variations of GSI and maturation stages were confirmed in April to August as spawning season and June as peak spawning month. Fulton’s condition factor (KF) was found to be with significant relations with GSI values. Fecundity was 1,730 to 23,870 and significantly correlated with both TL and BW. Temperature has been increasing 0.029 °C/year with the falling of rainfall at 2.96 mm/year in the study area. Environmental factors -Temperature, rainfall, dissolved oxygen and pH were found to be significantly correlated with GSI. We found the optimal range of temperature (29–31 °C), rainfall (350–380 mm), dissolved oxygen (5.0–6.0 mg/l) and pH (7.1–7.5) for spawning of H. fossilis. The paper recommended the policy guidelines to pave the ways of the aquaculture, conservation and management of H. fossilis in the changing eco-climatic events through specific management measures.

This paper reports the first benchmarking of smallholder tilapia farming practices in rural northern Zambia, measuring fish growth, feed utilization and water quality parameters, using a participatory action research approach. The effects of three different feeding regimes that are currently used in smallholder farming systems in northern Zambia on the growth of the native tilapia, Oreochromis macrochir, were tested with 15 farmers (40% female), each having three ponds (one pond per feed treatment per farmer = 45 in total), over eight months in 2016–2017. The three feed treatments included: (1) formulated feed only comprising maize and soybean; (2) goat manure only; and (3) formulated feed and manure together. Three hundred (300) O. macrochir mixed-sex fingerlings, 0.5 ± 0.1 g average weight, were stocked in each pond. Water quality (pH, dissolved oxygen, and water temperature and transparency) was measured monthly, as was fish growth in each pond by randomly sampling thirty (30) fish and taking individual weights and lengths. Results showed that the water quality parameters were broadly similar in the different feed treatments over the eight-month experiment period, except for the water transparency values that were higher in the feed only treatment when compared to the other two treatments at months four through eight. Means for survival rate, weight gain, specific growth rate, total amount of fish harvested, and yield were all higher for the feed and manure together treatment than the other two feed treatments at the end of the experiment. A linear mixed-effects regression analysis that controlled for several fixed effects and included pond as a random effect found that the feed and manure together treatment increased fish growth by 10.8 ± 3.7 g at month eight compared to the manure only treatment. The analysis also found a negative effect on fish growth (−9.4 ± 3.8 g) in ponds that used the feed only treatment. The pond effect accounted for 10.1% of the total variance in the data at month eight. Future research and development efforts in Zambia should examine more closely the factors that influence fish growth and that make up the pond effect to determine which innovations and better management practices could help smallholder farmers increase the productivity of their ponds.

This paper estimates metabolic rate and physiological response associated with different activity intensities through controlled climate chamber experiments. We investigate the effect of activity intensity, personal and environmental factors on the subjects' heart rate, oxygen consumption, energy expenditure, and metabolic rate (Mr). Forty-eight adult Indian subjects categorized based on age, gender, Body Mass Index (BMI), ethnicity and dietary practices are subjected to different temperature, relative humidity, and air velocity set-points. Cardio-Pulmonary Exercise Test (CPET) and Resting Metabolic Rate (RMR) Test are performed in a climate camber based on appropriate experimental protocols. We find substantial variation in the physiological responses concerning activity intensity. The difference in Mr for different age and BMI groups is statistically significant. Mr of stationary activities exhibits marginal variation with temperature change. However, Mr of non-stationary activities shows significant variation with temperature variations. The effect of relative humidity on Mr is significant for non-stationary activities. Ethnicity and dietary habits of the subjects depict good relationship with the mean Mr for non-stationary activities. There is a significant difference observed in the metabolic stabilisation period for different age group categories in non-stationary activities. We present the impact of these intrinsic variations of Mr on thermal comfort estimations.

The Red Maasai are indigenous sheep breeds known for their adaptability in arid and semi-arid environments while the Dorper is known for its good mutton production. A field experiment cross breeding program for the two breeds was set up in 2003 to exploit these traits. In this paper, we present the genetic parameters for birth weight (BWT), weaning weight (WWT) and weight at nine months (MWT) for pure Red Maasai (RRRR), pure Dorper (DDDD), 75% Dorper (DDDR) and 50% Dorper (DDRR) breeds. The genetic parameters were estimated by fitting four different multivariate animal models while ignoring or including maternal effects. The model with the lowest Akaike’s Information Criterion (AIC) was chosen as the best model for the estimation of genetic parameters. The average annual genetic gain of the studied traits for each breed group was estimated by regressing the estimated breeding values on year of birth. Records from 5442 lambs recorded over a period of 17 years (2003-2019) were used in this analysis. The breed group, sex, type of birth, season of birth and age of the dam significantly (P

Due to the characteristics of rapid transmission of COVID-19 and extended survival time on the plastic surface, resulting in a sharp increase in the number of microplastics (MPs) in sludge. In this paper, different amounts of terephthalate (PET) were added to four earthworm-assisted sludge treatment wetland (ESTW) reactors to investigate the effect of MPs on the operation process of ESTW. The results show that the addition of a small number of MPs had little effect on the ESTW reactor, and the negative impact was evident when a large number of MPs. The organic matter removal efficiency (TCOD 72.1%) and sludge stability (VS/TS 31.0%) of the ESTW4 reactor with 200000 particles/kg were the worst. The plant height, root length and chlorophyll growth of the ESTW4 reactor were significantly inhibited, and the yield of CAT increased significantly, which proved that a large number of MPs had noticeable side effects on plants. The number of MPs (35.21particles/kg) and small size MPs (62.6%) in earthworm casts reached maximum, CAT (38.1U/mg prot) and AChE (14.3U/mg prot) have the same trend in ESTW4. A large number of MPs during the ESTW reactor lead to an obvious oxidative stress reactions and lasting neurotoxicity of earthworm. Additionally, the type and quantity of bacteria in the ESTW reactor could reduce when the MPs adding too much.