Biosafety assessment of laying hens fed different treatments of black soldier flies (Hermetia illucens) under doxycycline stress.

The black soldier fly (BSF, Hermetia illucens) is a resource insect that can utilize livestock and poultry feces. However, BSFs may also increase the risk of transmission of antibiotic resistance genes (AGRs) that are widespread in livestock and poultry farm environments. Therefore, we aimed to evaluate the biosecurity risks of different BSF treatments in the laying chicken food chain using the "chicken manure-BSF-laying hens" model. Our results indicated that different BSF treatments significantly affected antibiotic residue, ARGs, MGEs, bacterial antibiotic resistance, and bacterial microbial community composition in the food chain of laying hens fed BSFs. These risks can be effectively reduced through starvation treatment and high-temperature grinding treatment. Comprehensive risk assessment analysis revealed that starvation combined with high-temperature milling (Group H) had the greatest effect.

Development of amine-sensitive intelligent film with MIL-100(Fe) as function filler based on anthocyanins/pectin for monitoring chilled meat freshness.

To enhance the amine-sensitivity of intelligent films for accurate monitoring of chilled meat freshness, different additions (0, 1, 2, 3 wt%) of MIL-100(Fe) were incorporated into the matrix composed of anthocyanins (ANs) and pectin (P). Results indicated that the tensile strength, thermal stability, barrier performance and absorption capacity of the films with MIL-100(Fe) were improved significantly (p < 0.05). Especially, the film with 2 % MIL-100(Fe) exhibited the best performance due to its compact structure and the highest crystallinity. Additionally, adsorption isotherms of the films with MIL-100(Fe) were fitted on the Langmuir and the Freundlich isotherm, and adsorption kinetics were fitted on the pseudo-second-order model and Elovich model, respectively (R2 > 0.96), suggesting a combined mechanism of chemisorption and intraparticle diffusion. Besides, when the films were exposed in ammonia environment, they changed color from purple to blue-violet, finally to green. Ultimately, film with 2 % MIL-100(Fe) was used to monitor the chilled meat freshness, as expected, similar color variation was observed at three stages of meat freshness (fresh, sub-fresh, and spoiled), which enabled the accurate differentiation of meat freshness. Thus, films with MIL-100(Fe) demonstrated the potential to be amine-sensitive intelligent packaging for monitoring chilled meat freshness in real time.

[Decreased expression of aquaporin 4 (AQP4) in brain tissue of rats with thermoplegia is associated with encephaledema].

Objective To study the characteristics of the expression of aquaporin-4 (AQP4) in the brains and astrocytes of rats with thermoplegia. Methods Sixty healthy male Sprague-Dawley rats weighing (250±30) g were randomly divided into control group and model group. The quiet exposure method with high temperature (40DegreesCelsius) and high humidity (70%) was used to make a typical rat model of thermoplegia to monitor rectal temperature and record onset time every 10 minutes. When the temperature of stressed rats reached 42.5 DegreesCelsius, it was regarded as onset time of the disease. The rats in both groups were placed at 26DegreesCelsius with humidity 60% later. After 5-hour observation and their behavior evaluation, the rats were killed and their brain tissues were taken for measuring the water content of the tissues. The astrocytes of the rats were cultured at 37DegreesCelsius and 41DegreesCelsius. AQP4 mRNA and protein expression were detected by reverse-transcription PCR and Western blot analysis. Results Compared with the control group, the expression of AQP4 mRNA and protein were significantly lower in the model group than in the control group. Conclusion High temperature may lead to the destruction of blood-brain barrier and the down-regulation of AQP4 mRNA and protein expression in experimental rats, which can induce the occurrence and development of cerebral edema in experimental rats.