Search Results (154)

This study presents findings from two discrete experimental processes that examined the impact of lameness events on two consecutive, critical time points in the annual production cycle of dairy cattle (early in puerperium—first study, and later at the onset of the reproductive period—second study) regarding liver function, glucose levels, milk production, body condition score, and back fat thickness. In the first study, 47 cows (lame group n = 22, control group n = 25) were monitored from 10 days ante partum (ap) to 46 days post-partum (pp). In the second study, 79 cows (lame group n = 52, control group n = 27) were monitored from day 28 ± 5 pp to day 65–72 ± 5 pp. Lame cows had greater gamma-glutamyl transferase (GGT) concentrations in the blood serum compared to control cows (25.83 vs. 23.56, p = 0.02, respectively) early in puerperium, whereas the two groups did not differ in the second study. The concentration of glutamate dehydrogenase (GLDH) was lower for lame compared to control cows in both studies (17.24 vs. 24.60, respectively, p = 0.02 in the first study, and 30.50 vs. 51.10, respectively, p = 0.02 in the second study). The concentrations of aspartate transaminase (AST) and glucose did not differ between groups in both studies. Lame cows had a lower body condition score (BCS) and backfat thickness (BFT) scores compared to the control in both studies overall. The lame cows of the first study experienced a significant loss of milk production, especially during the second month of lactation, while in the second study, milk production remained unaffected. Conclusively, lame cows have lower BCS and BFT values, whereas milk yield can be negatively affected only if lameness occurs early in the puerperium, probably beginning at the dry period. However, the current research shows that acutely lame cows, as described in this study, exhibit only mild alterations in liver function compared to non-lame ones. Full article

This paper introduces RWA-BFT, a reputation-weighted asynchronous Byzantine Fault Tolerance (BFT) consensus algorithm designed to address the scalability and performance challenges of blockchain systems in large-scale IoT scenarios. Traditional centralized IoT architectures often face issues such as single points of failure and insufficient reliability, while blockchain, with its decentralized and tamper-resistant properties, offers a promising solution. However, existing blockchain consensus mechanisms struggle to meet the high throughput, low latency, and scalability demands of IoT applications. To address these limitations, RWA-BFT adopts a two-layer blockchain architecture; the first layer leverages reputation-based filtering to reduce computational complexity by excluding low-reputation nodes, while the second layer employs an asynchronous consensus mechanism to ensure efficient and secure communication among high-reputation nodes, even under network delays. This dual-layer design significantly improves performance, achieving higher throughput, lower latency, and enhanced scalability, while maintaining strong fault tolerance even in the presence of a substantial proportion of malicious nodes. Experimental results demonstrate that RWA-BFT outperforms HB-BFT and PBFT algorithms, making it a scalable and secure blockchain solution for decentralized IoT applications. Full article

Blockchain technology is an emerging decentralized and distributed technology that can maintain data security. It has the potential to transform many sectors completely. The core component of blockchain networks is the consensus algorithm because its efficiency, security, and scalability depend on it. A consensus problem is a difficult and significant task that must be considered carefully in a blockchain network. It has several practical applications such as distributed computing, load balancing, and blockchain transaction validation. Even though a lot of consensus algorithms have been proposed, the majority of them require many computational and communication resources. Similarly, they also suffer from high latency and low throughput. In this work, we proposed a new consensus algorithm for consortium blockchain for a leader selection using the reputation value of nodes and the voting process to ensure high performance. A security analysis is conducted to demonstrate the security of the proposed algorithm. The outcomes show that the proposed algorithm provides a strong defense against the network nodes’ abnormal behavior. The performance analysis is performed by using Hyperledger Fabric v2.1 and the results show that it performs better in terms of throughput, latency, CPU utilization, and communications costs than its rivals Trust-Varying Algo, FP-BFT, and Scalable and Trust-based algorithms. Full article

Wireless technologies now take every part of one’s everyday life. As such, it will be no longer a surprise if a blockchain system is composed of wirelessly connected nodes. However, wireless communication is known for its inherent unreliability caused by noise, interference, limited bandwidth, etc. Motivated by this fundamental problem, this paper investigates the impact of wireless communications on the performance of three representative consensus mechanisms, viz., proof of work (PoW), proof of stake (PoS), and proof of coverage (PoC). It features a comprehensive analytical framework that mathematically derives metrics quantifying the scalability and the level of decentralization of the three consensus mechanisms, constituting a key contribution of this work. The paper then proceeds to present extensive simulation results as a means to confirm the underpinning theoretical findings. Overall, we emphasize that the framework’s holisticity will allow it to be applied to diverse consensus mechanisms. Full article

Biofloc technology (BFT) is an advanced aquaculture method that uses microbial communities to enhance water quality and support aquatic species cultivation. Our research aims to delve into the pivotal role of aeration intensity within BFT systems, revealing its influence on microbial community structures, water quality, and nutrient cycling for L. vannamei culture. Three aeration levels were set with intensities of V75 (75 L/min), V35 (35 L/min), and V10 (10 L/min). The results showed that the lowest aeration intensity (V10) resulted in larger floc sizes and a reduction in the 2D-fractal dimensions, indicating a decreased overall structural complexity of the bioflocs. In addition, water quality parameters, including total ammonia nitrogen and nitrite, remained low across all treatments, highlighting the water-purifying capacity of biofloc. While protein and lipid contents in biofloc did not differ significantly among treatments, docosahexaenoic acid (DHA) levels were highest in the V75 treatment, suggesting that higher aeration promotes the accumulation of essential fatty acids. RDA analysis revealed that microorganisms like Ruegeria sp. and Sulfitobacter mediterraneus negatively correlated with ammonia and nitrite levels, suggesting their key role in converting ammonia to nitrite and nitrate in marine nitrogen cycles. The functional annotation of metagenomes across different aeration levels showed the similarly active roles of microorganisms in nitrogen metabolism and protein synthesis. In conclusion, while variations in aeration intensity affect floc size and the accumulation of essential fatty acids in biofloc, they do not significantly impact overall water quality or core microbial functions in L. vannamei aquaculture. Future research should focus on the effects of aeration strategies on microbial community dynamics and the integration of these data with performance metrics in L. vannamei. These insights can help optimize biofloc cultivation and enhance environmental sustainability in the aquaculture industry. Full article

Donkey slaughter in West Africa has received limited scientific attention, despite increasing over recent years. This study aimed to explore factors affecting donkey welfare, both ante-mortem and at slaughter, in the Upper East region of Ghana. A total of 134 donkeys at five different slaughter points were assessed using animal-based indicators. Slaughter involved either blunt force trauma (BFT) using a wooden pole (1 location) or a metal hammer (2 locations); or non-stun ventral neck incision (VNI) (2 locations). Time to loss of consciousness (or return) was assessed, with behavioural and brainstem signs of sensibility/consciousness. Negative human–animal interactions occurred ante-mortem, with animals struck multiple times and handled using aversive methods. Donkeys hit on the head with the wooden pole were five times more likely to be ineffectively concussed (p < 0.001, OR: 5.4, CI: 1.9–15.4) compared to the hammer and took significantly longer to lose consciousness (p < 0.001). The mean time to loss of corneal reflex for those hit by wooden pole was 166.9 s (SD 21.1; range: 79–425 s), compared to just one animal displaying corneal reflex for 59 s after being hit by metal hammer. For those animals slaughtered through VNI, corneal reflex was observed for a mean time of 96.5 s (SD 4.3, range 26–164 s). The findings of this study highlight major concerns regarding the methods used for donkey slaughter in the Upper East region in Ghana, particularly regarding aversive ante-mortem handling and prolonged time to loss of consciousness during VNI and ineffective BFT in inducing unconsciousness by concussion. Full article

This study evaluated water quality, growth, and partial budget analysis (PBA) for Penaeus vannamei, comparing super-intensive Biofloc Technology (BFT) and Recirculating Aquaculture Systems (RAS). The 69-day trial used 100 L units with two treatments (RAS and BFT), each with three replicates. Shrimp were initially reared in a 30-day nursery to a weight of 0.10 ± 0.04 g and then stocked at 500 shrimp m⁻³. Biofloc growth in BFT was promoted by maintaining a C:N ratio of 15:1, adding dextrose when total ammonia nitrogen (TAN) reached 1 mg L⁻¹. Probiotics (3 g m⁻³) were administered daily to both groups. TAN levels in BFT initially spiked but stabilized after 36 days. Vibrio abundance was initially higher in RAS, but by the end of the trial, it was higher in BFT. Final weight, weekly growth ratio, and yield were greater in BFT, whereas feed conversion ratio (FCR) and water use were higher in RAS. Survival rates were 83.33% in BFT and 88% in RAS. BFT achieved a superior net benefit/cost compared to RAS. Although RAS more effectively controlled nitrogenous compounds, BFT exhibited better growth performance, with higher final weights, lower FCR, and better Vibrio management. The partial budget analysis indicated an economic advantage for BFT, with a net positive benefit of $2270.09 when shifting from RAS to BFT due to lower operating costs and higher shrimp yield. Among these two sustainable production systems, BFT was more productive while utilizing less natural resources. Full article

The study investigates the economic aspects of red tilapia (Oreochromis sp.) production using biofloc technology under different electrical energy sources. Conducted at the El Vergel Fish Farming Association in Arauca, Colombia, the study examines four energy treatments: conventional energy (CE), combined conventional and photovoltaic energy (CPVE), full photovoltaic energy (PVE), and simulation of photovoltaic energy generating surplus for nighttime use (PVES). The water quality and zootechnical performance met the species requirements, with dissolved oxygen decreasing as fish size increased. The PVE treatment had the highest initial investment due to solar panels and battery costs, but it also had the lowest operating energy costs. However, the overall costs of the PVE treatment increased due to depreciation and maintenance. Feed was the largest production cost, followed by labor in most treatments, while depreciation was a major cost for the PVE treatment. The total operating cost (TOC) of the photovoltaic energy systems (PVE and PVES) was lower compared to that of conventional energy (CE), with PVES showing the highest cost savings. The reduction in energy costs highlights the potential for solar energy systems to enhance the economic viability of aquaculture production, making these systems a favorable option for sustainable production in the long term. Full article

This review evaluates regenerative aquaculture (RA) technologies and practices as viable pathways to foster resilient, ecologically restorative aquaculture systems. The key RA technologies examined include modern periphyton technology (PPT), biofloc technology (BFT), integrated multitrophic aquaculture (IMTA), and alternative feed sources like microalgae and insect-based diets. PPT and BFT leverage microbial pathways to enhance water quality, nutrient cycling, and fish growth while reducing environmental pollutants and reliance on conventional feed. IMTA integrates species from various trophic levels, such as seaweeds and bivalves, to recycle waste and improve ecosystem health, contributing to nutrient balance and reducing environmental impact. Microalgae and insect-based feeds present sustainable alternatives to fishmeal, promoting circular resource use and alleviating pressure on wild fish stocks. Beyond these technologies, RA emphasizes sustainable practices to maintain fish health without antibiotics or hormones. Improved disease monitoring programs, avoidance of unprocessed animal by-products, and the use of generally recognized as safe (GRAS) substances, such as essential oils, are highlighted for their role in disease prevention and immune support. Probiotics are also discussed as beneficial microbial supplements that enhance fish health by promoting gut microbiota balance and inhibiting harmful pathogens. This review, therefore, marks an important and essential step in examining the interconnectedness between technology, agroecology, and sustainable aquaculture. This review was based on an extensive search of scientific databases to retrieve relevant literature. Full article

Background: The resection of tumors of the proximal fibula includes the removal of the lateral collateral ligament (LCL) and biceps femoris tendon (BFT) attachment. The aim was to describe and evaluate a surgical reconstruction technique in terms of functional outcome and knee joint stability. Methods: We analyzed the outcome of six patients, treated by a proximal fibula resection. The reconstruction of the attachments of the LCL and BFT was performed with two suture anchors, fixed onto the tibia at the level of the proximal tibiofibular joint (PTFJ). The postoperative knee flexion strength as well as the lateral knee joint stability were compared to the contralateral side using a digital scale and stress X-ray. Patient-reported outcome measures and postoperative complications were documented. Results: No lateral instability and no significant loss of knee flexion strength could be observed (p = 0.075). One persistent postoperative peroneus paresis was reported. High functional outcome was achieved with a mean MSTS score of 92.2%. Conclusions: The resection of the proximal fibula with the reinsertion of the LCL and the BFT using bone anchors in the PTFJ seems to provide a good functional outcome, with a low level of associated comorbidities. Full article

This review aims to advance the development of biofloc technology (BFT), providing more sustainable and efficient practices for the farming of the Japanese sea cucumber (Apostichopus japonicus). BFT is a sustainable aquaculture method that promotes nutrient recycling and effective carbon source management, offering significant advantages such as improving water quality, enhancing growth performance, and boosting the physiological activity and disease resistance of cultured animals. In A. japonicus farming, the optimal carbon source is glucose, and the ideal carbon-to-nitrogen (C/N) ratio ranges between 15 and 20. Microbial additives, such as the Bacillus species, have been shown to enhance biofloc formation and growth, as well as the immune responses in A. japonicus. However, the technology also faces limitations, including finding suitable biofloc culture protocols that match the physiological habits of A. japonicus and potential challenges with biofloc stability under varying environmental conditions. Based on existing research, this review discusses these limitations in the farming of A. japonicus. Additionally, it compares biofloc farming models for other economically important aquatic species. By addressing these key aspects, this review offers insights to enhance BFT performance, ultimately contributing to more efficient and sustainable A. japonicus aquaculture practices. Full article

Blockchain consensus mechanisms play a critical role in ensuring the security, decentralization, and integrity of distributed networks. As blockchain technology expands beyond cryptocurrencies into broader applications such as supply chain management and healthcare, the importance of efficient and scalable consensus algorithms has grown significantly. This study provides a comprehensive bibliometric analysis of blockchain and consensus mechanism research from 2014 to 2024, using tools such as VOSviewer and R’s Bibliometrix package. The analysis traces the evolution from foundational mechanisms like Proof of ork (PoW) to more advanced models such as Proof of Stake (PoS) and Byzantine Fault Tolerance (BFT), with particular emphasis on Ethereum’s “The Merge” in 2022, which marked the historic shift from PoW to PoS. Key findings highlight emerging themes, including scalability, security, and the integration of blockchain with state-of-the-art technologies like artificial intelligence (AI), the Internet of Things (IoT), and energy trading. The study also identifies influential authors, institutions, and countries, emphasizing the collaborative and interdisciplinary nature of blockchain research. Through thematic analysis, this review uncovers the challenges and opportunities in decentralized systems, underscoring the need for continued innovation in consensus mechanisms to address efficiency, sustainability, scalability, and privacy concerns. These insights offer a valuable foundation for future research aimed at advancing blockchain technology across various industries. Full article

Biofloc technology (BFT) systems heavily rely on microbiota to mitigate ammonia toxicity and manage essential nutrient cycling. Understanding the diversity and functional role of microbiota within BFT-applied aquaculture systems is crucial for ensuring sustainable operations. Though some studies exist on BFT microbiota, research on microbial differences in Japanese eel aquaculture is still limited, hindering the wider application of BFT systems. In this study, we analyzed the characteristics of water quality factors and microbiota in Japanese eel (Anguilla japonica) breeding water, applying the BFT system. Using a metabarcoding approach, the diversity and community structure of aquatic microbiota were compared between BFT and continuous flow (CF) systems. The pH was significantly higher in CF water, while total ammonia nitrogen (TAN) and nitrite (NO₂⁻-N) was higher in BFT water. Alpha diversity was significantly higher in BFT compared to CF systems, and it was correlated significantly with pH and TAN. In both BFT and CF water, the phyla Proteobacteria and Bacteroidota were found to be the most abundant. In the BFT water, a diverse array of bacterial taxa, including BFT-specific clades, were consistently present, while the microbiota in CF water was more variable and contained fewer specific taxa. In addition, bacterial functions related to nitrate reduction, sulfur compound oxidation, and chitinolysis were significantly more abundant in BFT than in CF systems. These findings highlight differences in water quality and microbiota between aquaculture systems, which can inform future research on the use of BFT for sustainable fish farming. Full article

This study aimed to evaluate and compare the effects of biofloc technology (BFT) and clear water (CW) on water quality physiological and productive performance of juvenile freshwater Northern River shrimp, Cryphiops caementarius under three stocking densities (100, 200, and 400 shrimp m⁻²). Shrimp with an initial body weight of 0.44 ± 0.07 g were stocked in 18 rectangular fiberglass tanks with a water volume 150 L for 290 days. During the experiment, water quality parameters stayed within acceptable ranges for shrimp growth. The highest survival rate was recorded in BFT treatments; however, the growth performance of shrimp in the treatments with the lowest stocking density was higher than that with the highest stocking density, regardless of whether BFT or CW was used. Transcriptional levels of heat shock protein (Hsp70) and superoxide dismutase (SOD) showed significant differences (p < 0.05) between treatments, particularly in BFT. These results indicate that an initial stocking density of 200 shrimp m⁻² appears to be appropriate for shrimp juveniles cultured in a BFT system. Thus, this technology emerges as an effective tool for river shrimp farmers looking to increase their stocking densities and improve the efficiency of their production systems in arid zones. Full article

The incorporation of aquaponics into saline integrated multitrophic aquaculture (IMTA) systems, employing biofloc technology (BFT), relies on the cultivation of halophytes capable of withstanding the physical–chemical conditions created by the unique microbial communities in BFT systems. This study aimed to evaluate the integration of the halophyte Salicornia neei with tilapia (Oreochromis niloticus) and marine shrimp (Litopenaeus vannamei) reared in BFT systems dominated by chemoautotrophic (CHE) and heterotrophic (HET) microorganisms over a period of 84 days in southern Brazil. Each BFT treatment had three replicates, composed of IMTA units. The stocking densities were 400 ind. m⁻³ (17 m³ circular tanks), 44 ind. m⁻³ (4 m³ circular tanks), and 30 ind. m⁻² (4.8 m² hydroponic benches) for shrimp, fish, and halophyte, respectively. The highest S. neei individual shoot production (up to 31 g per 30 days) was observed in the CHE treatment, along with favorable agronomic characteristics, possibly due to overall elevated nitrate (98.41 mg N−NO₃ L⁻¹) and phosphate concentrations (4.62 P−PO₄ L⁻¹). Shrimp in the CHE treatment displayed higher average final weight, specific growth rate, productivity, and survival (11.24 g, 2.88% day⁻¹, 3.86 kg m⁻³, and 90%, respectively) compared to the HET treatment. Results indicated no significant difference in tilapia zootechnical performance between treatments. Full article