Physiological and Molecular Responses in the Gill of the Swimming Crab Portunus trituberculatus During Long-Term Ammonia Stress

Ammonia is a common environmental stressor encountered during aquaculture, and is a significant concern due to its adverse biological effects on vertebrate and invertebrate including crustaceans. However, little information is available on physiological and molecular responses in crustaceans under long-term ammonia exposure, which often occurs in aquaculture practices. Here, we investigated temporal physiological and molecular responses in the gills, the main ammonia excretion organ, of the swimming crab Portunus trituberculatus following long-term (4 weeks) exposure to three different ammonia nitrogen concentrations (2, 4, and 8 mg l–1), in comparison to seawater (ammonia nitrogen below 0.03 mg l–1). The results revealed that after ammonia stress, the ammonia excretion and detoxification pathways were initially up-regulated. These processes appear compromised as the exposure duration extended, leading to accumulation of hemolymph ammonia, which coincided with the reduction of adenosine 5′-triphosphate (ATP) and adenylate energy charge (AEC). Considering that ammonia excretion and detoxification are highly energy-consuming, the depression of these pathways are, at least partly, associated with disruption of energy homeostasis in gills after prolonged ammonia exposure. Furthermore, our results indicated that long-term ammonia exposure can impair the antioxidant defense and result in increased lipid peroxidation, as well as induce endoplasmic reticulum stress, which in turn lead to apoptosis through p53-bax pathway in gills of the swimming crab. The findings of the present study further our understanding of adverse effects and underlying mechanisms of long-term ammonia in decapods, and provide valuable information for aquaculture management of P. trituberculatus.

Correlation of Asthma with Ammonia Exposure and Other Risk Factors among Informal Workers of Poultry Farmers

Objective: To determine the prevalence of asthma and its corelation with ammonia exposure among informal workers of poultry farmers.Method: This study design was a cross-sectional analytic to 69 respondents using questionnaires, field observation, physical examination, spirometry measurement, and peak flowmeter test to diagnose work-related asthma and measurement of ammonia level in air environment of farm. All variable were bivariate tested by using Chi-square test or Fischer test. The variables which have p value <0,25 were included into multivariate analysis by using binary logistic regression.Results: The prevalence of asthma in poultry farmers was 21,74%. In bivariate analysis, there was a significant corelation between working periode (p = 0,035 with OR = 7,00) and smoking habit (p = 0,018 with OR = 5,603) with asthma. There was no significant corelation between age, sex, nutritional status, work location, education level and marital status with asthma. The result of measurement of ammonia level in the poultry farm enclosure on average is 2,329 ppm. Multivariate analysis was performed on several risk factors that fulfilled the requirement p <0,25 ie working periode, smoking habit, nutritional status, and work location. From the results of mutivariate found that workers with a history of smoking habits have the strongest corelation p = 0,013 with OR 17,305.Conclusion: The prevalence of asthma in poultry farmers was 21,74%. There was no significant corelation between ammonia exposure in the work environment with asthma. But there was a significant corelation between working periode and smoking habit with asthma.