Pelleted Feed Research Articles

Effects of Formulated Pellet Feed or Live Fish Food on the Intestinal and Aquaculture Water Microbial Communities in Goldfish, Carassius auratus

This study investigates the impact of different diets on fish growth and bacterial community structure present in the intestine of goldfish (Carassius auratus) and their aquaculture water under recirculating water conditions. We assumed that different types of diet would form different intestinal microbiota that may affect host growth. Using Illumina MiSeq high-throughput sequencing, we analyzed bacterial communities in goldfish fed with formulated pellet feed, Tubifex worms (Limnodrilus hoffmeisteri), and an alternating diet of both. Over a 14-day feeding trial, no significant differences in juvenile goldfish growth were observed between groups. After 7 days, diet changes significantly influenced the abundance and diversity of intestinal bacteria, with the alternating diet notably enhancing bacterial diversity in both the intestines and water. However, these differences in bacterial diversity decreased by day 14. The results indicate that diet type affects microbial community diversity in the intestines and water of goldfish, and that goldfish intestines maintain a stable core bacterial community structure. This highlights the potential for optimizing diet types to enhance microbial health and stability in aquaculture systems and, in addition, provides an important scientific basis for alternative diets in goldfish aquaculture in the industry.

Effects of Nesting Material and Housing Parameters on Feed Wastage Behavior in Female Swiss Webster Mice.

Feed wastage in laboratory mice, also known as chewing or grinding behavior, is problematic for program management and animal welfare. The destruction of pelleted feed without consumption produces a powder accumulation on the cage floor called orts. Ort accumulation disrupts the cage microenvironment and can clog Lixits resulting in flooding. Moreover, added labor adds cost, and cage disruption increases animal stress. Published studies examining the behavior and ways to mitigate it have had inconsistent results, and the cause or causes have not yet been fully identified. The purpose of this study was to identify methods to reduce the development of chewing behavior in laboratory mice. Female Swiss Webster (Tac:SW) mice (n = 144) were randomly assigned to one of 8 groups (12 cages per group) with 2 housing densities (single and pair) and 4 nesting material paradigms. Mice were housed on clean bedding for 8 wk and then soiled bedding for the next 8 wk. Chewing behavior was evaluated by feed weight, cage weight, and feed scores. The addition of a Diamond Twist significantly increased ort production, while nest transfer decreased it but not significantly. Pair housing increased overall orts but not when adjusted for animal number. These results identified potential contributing factors to chewing behavior. However, further research is needed to elucidate the exact causes and solutions.

Comparing Different laboratory Methods for Measuring the Feed Pellet Durability

Comparing Different laboratory Methods for Measuring the Feed Pellet Durability

Effect of tarhana soup on serum lipid profile in BALB/c male mice fed a high-fat-diet

Aim: With industrialization, there has been an increase in chronic diseases due to continuous change of nutrition. Tarhana is a traditional grain-based product fermented by lactic acid bacteria in Turkish cuisine. This study aims to evaluate possible effects of tarhana on the impaired lipid profile parameters and serum glucose values in male BALB/c mice fed a high-fat diet. Materials and Methods: Male BALB/c mice were grouped into three different strain male mice groups: control group (n=10), high fat diet (HFD) (n=10) and high fat diet supplemented with tarhana (n=10). Standard pellet feed was given to the control group, high-fat feed with 60% fat content in the HFD group, high-fat feed and 0.3 mL (8-10mL/kg) of tarhana were given to the other group. Results: A significant difference was detected in epididymal fat weights, lipid profiles and serum glucose values between the groups (p<0.05). Conclusion: It may have beneficial effects in many metabolic diseases, especially coronary heart disease and diabetes with its positive effects on lipid profile, epididymal adipose tissue and glucose level.

Penerapan Mesin Pencetak Pelet Untuk Pakan Ternak Di Desa Sambigede Pakisaji Malang

Sambigede Village, District. Pakisaji is one of the areas that has high potential in the livestock sector in Malang Regency, the potential is around 20 thousand poultry, 100 cattle, and there are also 3 fish farming groups. So far, the animal feed pellets given by breeders are natural feed in the form of bran and other grains. Animal feed pellets, which are often referred to as pellets, are one of the most important things to pay attention to in the livestock industry, Pellets are a source of nutrition that has a huge impact on livestock, especially poultry breeders, but breeders in this village still have difficulty producing pellets because limited knowledge and technology. So it is necessary to implement an animal feed pellet printing technology machine to provide animal feed pellets in the form of feed pellets independently. The aim of this community service is to diffuse Appropriate Technology for animal feed pellet printing machines by providing knowledge and skills about how to make feed pellet products, and operation and maintenance of animal feed pellet printing machines to partners. Based on the implementation that has been carried out, production increases can be actualized to increase the production of feed pellets 40 kg/hour, so that the implementation of an animal feed pellet printing machine can provide a relatively large contribution to increasing productivity, quality, and turnover for community groups in Sambigede Village, Pakisaji, Malang.. Kata Kunci: pellet machine, pellet press machine, appropriate technology

Experimental Research on Breakage Characteristics of Feed Pellets under Different Loading Methods

Particle breakage is a common phenomenon during the processes of production, storage, and transportation. Because of the requirements for pellet integrity in poultry farming, research on the breakage characteristics of feed pellets is necessary. In this paper, repeated compression tests under different loading forces and repeated impact tests under different air pressures were carried out with feed pellets as the research object. The breakage behaviors were described, and the particle size distribution of feed pellets was analyzed quantitatively. The results revealed a positive correlation between crack density in feed particle beds and loading force. The compression process was divided into three stages based on force–displacement curves. The size of the feed pellets during repeated impacts decreased continuously and was negatively correlated with air pressure. The Weibull function accurately described the particle size distribution, with R2 values exceeding 0.97 and 0.96. The Weibull parameters showed a steady breakage degree in compression tests and a growing breakage degree in impact tests. The variation in energy and pulverization rate under different loading conditions was examined as the number of loading cycles increased. The relationship between energy and pulverization rates was fitted, showing that both parameters increased with loading cycles in different loading methods. The model of Vogel and Peukert could describe the relationship between energy and pulverization rate well, with R2 values exceeding 0.94. The minimum energy required for pellet breakage was higher in compression than in impact due to the compaction of the feed particle bed during repeated compression. The results can provide basic theory and data support for breakage characteristics and quality evaluation of feed pellets.

Functional morphology and ontogeny of mouthparts and mouth aperture of Panulirus ornatus and Sagmariasus verreauxi: Implications towards formulated feeds development

Development of formulated feed is now a focal point in advancing the aquaculture of spiny lobster species. This study investigated the functional morphology of two spiny lobsters, Panulirus ornatus and Sagmariasus verreauxi, by analysing mouthpart morphology and mouth aperture. The analysis is focussed on determining likely feed preference based on morphology with the aim to provide knowledge for the development of formulated feeds. There is a strong correlation between the mouth aperture being approximately 4.0 and 7.5% of the carapace length of S. verreauxi and P. ornatus juvenile and adult lobsters, respectively. This finding provides knowledge for development of a species-specific tool that could be used in experimental studies to define optimal dimensions of artificial manufactured pellets in relation to the size of the lobster. Differences in mouthpart morphology through ontogeny included increase of calcification and robustness, and this is likely to reflect a different requirement in the texture (softness/hardness) of the pellet as the animals develop. Spines and setation are a prominent feature of the mouthpart morphology and differ between species and during ontogeny. Spines on maxillipeds II and III and crista dentata on maxillipeds III are likely to play an important role in holding and manipulation of feed prior to ingestion. Pellet texture may need to accommodate these differences in species and age specific mouthpart ontogeny. Ontogenetic changes in setation were found, with much richer setation proportionally to the size of mouthpart in first instar juvenile lobsters, which decreases with size increase. Furthermore, species-specific differences indicate function shifts in mouthparts with life stages. This may indicate differences in filter feeding capacity with age and between species, as reported for other decapods. This is unlikely to be of high importance in pellet feeding but may represent an avenue of investigation for first feeds in juveniles. Collectively, the differences during ontogeny and between species suggest that formulated feeds may need to be tailored to species and life stage, particularly regarding pellet dimensions and texture.

Effects of high-level dietary distillers dried grains with solubles supplemented with multienzymes on growth performance, nutrient utilization, intestinal morphology, and pellet quality in broiler chickens.

With the increasing cost of bulk raw materials and advancements in the feed enzyme industry, corn distillers dried grains with solubles (DDGS) have shown more opportunities for use in broiler diets. Supplementation with multiple enzymes could mitigate anti-nutritional factors in DDGS, enhance nutrient digestibility, and thereby increase its utilization in broiler diets, leading to reduced feed costs. This study evaluated the effects of multienzyme supplementation on growth performance, nutrient utilization, intestinal morphology, and pellet quality in broiler chickens fed diets containing conventional levels of DDGS (C-DDGS) and higher levels of DDGS (H-DDGS). A total of 800 1-day-old Cobb 500 chicks was assigned to four dietary treatments with eight replicates of 25 birds each: C-DDGS (5% DDGS in Starter and 10% in Grower), C-DDGS + Enzyme (C-DDGS diet supplemented with multienzyme), H-DDGS (10% and 20%) + Enzyme (H-DDGS diet supplemented with multienzyme, 10% DDGS in Starter and 20% in Grower), and H-DDGS (15% and 30%) + Enzyme. The C-DDGS + enzyme diet increased (p < 0.05) body weight gain (BWG), reduced the feed conversion ratio, enhanced (p < 0.05) digestibility of dry matter (DM), crude protein, and hemicellulose (HC), and improved (p < 0.05) intestinal villus height and villus: crypt ratio of broilers. The H-DDGS (10% and 20%) + enzyme diet exhibited no difference in (p > 0.05) growth performance, nutrient digestibility (except HC), and intestinal morphological parameters, whereas the H-DDGS (15% and 30%) + enzyme diet decreased (p < 0.05) feed intake and BWG and reduced (p < 0.05) energy and DM digestibility by impact (p < 0.05) intestinal morphology compared with the C-DDGS enzyme-free diet. The H-DDGS diet had lower (p < 0.05) pellet hardness and poorer durability than the C-DDGS diet. Supplementing multienzyme in the C-DDGS (5% and 10%) diet improved growth performance from day 0 to 28 and diminished growth performance in the H-DDGS (15% and 30%) diet by influencing intestinal morphology and feed pellet quality in broiler chickens. In addition, when supplemented with multienzyme, the dietary DDGS level can be safely included at levels of 10% in 0-7 days and 20% in 8-28 days of age.

Alterations in captive Alexandrine parakeet (Palaeornis eupatria) gut microbiome and metabolome in response to dietary change

The Alexandrine parakeet (Palaeornis eupatria), also known as the Alexandrine parrot, is a critically endangered species in the world and a national second class protected animal. Current knowledge on gut microbiome and metabolome of captive Alexandrine parrots is limited. In the current study, we characterized the effect of dietary change with pellet feeding on the gut microbiome and metaboliome in Alexandrine parrots using 16S gene sequencing and liquid chromatography with tandem mass spectrometry (LC-MS/MS). Total of 12 Alexandrine parrots were used in a cross-over study with each period for 10 days. The results showed that dietary change with pellet feeding did not affect alpha indices of gut microbiota. Cyanobacteria, Firmicutes and Proteobacteria were the predominant bacterial phyla in the gut of Alexandrine parrot with Cynobacteria being the highest. Change of diet significantly increased the relative abundance of Actinobacteria and decreased Spirochaetota. The relative abundance of Fusobacteriota tended to increase with pellet feeding. No treatment effects were observed between the control and pellet feeding groups at the genus level. Based on the annotation results from Clusters of Orthologous Genes (COG) database, dietary change with pellet feeding significantly increased the relative abundance of genes coding for extracellular structures and lipid transport and metabolism. Metabolomics analysis combined with enrichment analysis revealed that dietary change altered the concentrations of gut metabolites as well as the metabolic pattern, and significantly affected the concentrations of fecal metabolites involved in isoflavonoid biosynthesis, flavonoid biosynthesis, nucleotide metabolism etc. In summary, dietary changes with pellet feeding affected the gut microbial composition and metabolites to some extent. The relevance of current findings to Alexandrine parrots' health and potential zoonosis need further exploring.

Screening of Organic Acid Type and Dosage in Drinking Water for Young Rabbits.

Organic acids (OAs) are employed in animal feed to regulate gastrointestinal disorders and diarrhoea thanks to their ability to modulate the gastrointestinal environment and their antimicrobial capacity. However, there is not enough evidence regarding the most adequate OA and its effectiveness in rabbit farming. Therefore, the aim of this study was to screen and evaluate the response of young rabbits to six OAs, administered via drinking water, at three different concentrations (pH levels). Organic acids (acetic, ACET; formic, FOR; propionic, PROP; lactic, LAC; citric, CIT; and butyric, BUT) were tested at three concentrations (pH 3, 4, and 5). A negative control (CON; non-acidified water) was also included. We used 240 weaned rabbits (28 days old) divided into 2 batches. In each batch, animals were randomly allocated to 1 of the 19 experimental treatments and were housed in group cages of 6 animals per cage, treatment, and batch. Among the 240 rabbits, an additional cage with 6 animals was included to determine the initial physiological state of the animals. All animals were fed with commercial pelleted feed throughout the whole experiment. The duration of the study was 7 days, until 35 days of age. At 31 and 35 days of age, in each batch, three animals per day and treatment were slaughtered. The pH of the digestive contents in the fundus, antrum, duodenum, jejunum, ileum, and cecum, as well as the gastric pepsin enzyme activity, was measured. Water and feed consumption per cage and individual body weight (BW) were recorded daily. The type and dosage of OAs affected water intake. ACET 3, PROP 3, and BUT 3 reduced water intake compared to CON, negatively impacting feed intake and weight gain. FOR and CIT acids led to the highest BW and weight gain at 35 days, compared to PROP, LAC, and BUT (p < 0.05); showing ACET intermediate values. While OAs had limited effects on gastric and small intestine pH, acidified water at pH 4 and 5 lowered ileum and caecum pH (p < 0.05) compared to pH 3. Acidified water at pH 4 showed the highest (p < 0.05) pepsin activity compared to pH 3 and pH 5. Considering the limited sample size and short-term assessment period of our screening test, the OAs with the highest potential for use in post-weaning rabbits were FOR, ACET, and CIT at pH 4. The selected combinations did not exhibit any early adverse effects in young rabbits. These results should be further confirmed in a broader population of animals. It would also be advisable to extend the application of OAs over longer periods to evaluate their effects throughout the entire growing period of rabbits.

Peculiarities of the existence of a focus cyatocephalosis among wild and cultivated salmon fishes in the reservoirs of the Izhora upland of the Leningrad region

One of the conditions for maintaining fish health in aquaculture is to control and prevent the presence of disease agents in the water supply sources of fish farms. The main advantages of industrial aquaculture to prevent the spread of parasites can be considered the use of groundwater and pellet feed. The use of an underground water source completely eliminates the possibility of the spread of parasites. In the case of using river, lakes or pounds water the consumption of pellets feed by fish should exclude their eating of invertebrates — intermediate hosts of parasites with a complex life cycle. However, we have found singles Cyathocephalus truncatus (Pallas, 1781) cestodes in juvenile rainbow trout in industrial conditions. This served as the basis for research on the spread of this parasite both in natural reservoirs and fish farms of various types located within the Izhora upland. Cyathocephalus truncatus cestode is a dangerous parasite with a complex life cycle that is widespread mainly in salmon fish. The paper presents experimental data highlighting the impact of fish farming factors and nutritional selectivity on the spread of the parasite. Special attention was paid to the infestation of Salvelinus lepecheni grown in the FSGCR in order to replenish the natural population. As a result of our research conducted over three years, fish of this species have not been invaded by the parasite in both industrial and experimental conditions. This indicates the safety of juveniles reproduced in the FSGCR for settlement in natural reservoirs. In order to determine the boundaries of the natural focus of cyatocephalosis, 106 specimens of salmon fish from 8 reservoirs were tested for infection. Methods of preventing disease in flowing pools are proposed. It has been suggested that the preservation of the focus is ensured by the progenis of the cestode procercoids, excluding the need for a definitive host (fish) to maintain the helminth population in isolated hydraulic water sources.

Evaluating the Effect of Live Brine Shrimp (Artemia franciscana) on Growth Performance in Ornamental Fish, Cyprinus rubrofuscus (Lacepede, 1803)

Feeding is a critical factor for both cultured and ornamental fish species. This study aimed to evaluate the effects of live brine shrimp (Artemia franciscana) on the growth and biochemical composition of fish. In the present study, sixty days feeding trail was conducted on the growth performance of ornamental fish, koi carp (Cyprinus rubrofuscus). The type of food such as live feed, nutrient-enriched prepared feed and commercial feed exerted a significant impact on the growth and body composition of fish. The specific growth rate is high in live brine shrimp fed fishes followed by prepared food. After 60 days experiment showed that the maximum length and weight of live brine shrimp fed fishes were 7.5 ± 0.9 cm and 5.3 ± 1.7 gm, respectively. The survival rates of the fish were 100 % under all feeding groups. The biochemical profiles of the fish varied significantly between the different feeding regimes. These results suggest that live feed is more effective than pelletized feed for ornamental fish culture.

Characterisation of discharge and flow rate predictions for asymmetric wedge-shaped hoppers

It is important to understand the flow behaviour inside wedge-shaped hoppers and accurately predict the discharge rate for the processing and handling of granular materials, regardless of whether the wedge hopper is symmetric or asymmetric. In this paper, the discrete element method (DEM) was used to reveal the flow behaviour of pellet feed in an asymmetric wedge-shaped hopper from the discharge rate, flow pattern, velocity distribution, normal contact force between particles and free-fall arch. The results showed that, with the hopper angle decreasing, the area of the active region of the particles increased, the stagnation zone decreased, and the free-fall arch became unstable. When the unilateral hopper angle was less than 45°, the discharge rate of the wedge-shaped hopper increased, and the average discharge rate reached the maximum value of 1.070 kg s−1 when the left and right hopper angles were equal to 15°. In addition, using the discharging mass proportion coefficient to represent the size of the region in which the unilateral hopper angle affected the flow of particles in the hopper, the hopper angle term in the Brown and Sellers model was corrected. The predictive errors of the corrected discharge rate model were less than 7.6% and 3.3% in the simulated and actual discharging tests respectively, which was better than that of the Brown and Sellers model. The results of the study could provide a theoretical basis for the intelligent upgrading of feed accurate handling equipment, and provide a reference basis for the design of asymmetric wedge-shaped hopper.

Intestinal flora analysis and serum metabolomics reveal the effectiveness of Bacillus coagulans BC66 in treating bacterial enteritis in bullfrogs

Bacterial enteritis is a major disease of bullfrogs that is characterized by rapid onset, high infectivity, and high mortality. This disease causes significant economic losses to the bullfrog farming industry and threatens food and environmental safety. Bacillus coagulans has gained more and more attention in the field of livestock and poultry replacement resistance due to its common advantages of acid-producing bacterial inhibition by Lactobacillus lactis and heat resistance of Bacillus subtilis suitable for feed pelleting. In this study, the therapeutic effect of B. coagulans BC66, administered as a feed supplement, on bacterial enteritis in bullfrogs was revealed based on intestinal flora analysis and serum metabolomics. Bullfrogs with bacterial enteritis were administered B. coagulans BC66 in feed for 20 days, where the concentration of the bacterial solution was 100 billion CFU/g, during which the number of treatments totaled 20, then studies were conducted to analyze intestinal histomorphology, the expression of intestinal proinflammatory factors, microbial diversity of the intestinal mucosa, immune indexes, and metabolite levels in serum. Compared with the untreated group, treatment of bullfrogs with B. coagulans BC66 resulted in repair of the intestinal tissue, a significant reduction in the expression of proinflammatory factors IL-1β, IL-8, IL-17, and TNF-α, increased diversity of microorganisms in the digestive tract, a decreased number of pathogenic bacteria, an increase in the number of probiotics, elevated levels of alkaline phosphatase, lysozyme, lactate dehydrogenase, glycolysin, and creatine kinase, upregulated levels of D-alkaline phosphatase, upregulated D-amino acid metabolism and aminoacyl-tRNA biosynthesis, and downregulated sphingolipid metabolic pathways. These results showed that B. coagulans could effectively treat bacterial enteritis in bullfrogs, increasing their survival rate, enhancing microbial homeostasis of the intestinal tract, reducing the occurrence of inflammation, and enhancing their immune ability. Taken together, the findings of this study provide insight that may aid the management of disease in the bullfrog farming industry, thereby ensuring improved food and environmental safety.

Effect of Adding Date Palm Pollen and Physical Diet Form on Productive Performance and Egg Quality of Female Quail

This experiment was conducted to estimate the main effect of adding Data palm pollen (DPP) and the form of diet on the productive performance of female quail compliant with: Hen day egg production (HD), Egg weight (EW), Egg mass (EM), Feed intake (FI) and Feed conversion ratio (FCR) and eggs quality of quail compliant with: Shape index (ShI %), shell weight (%), yolk weight (%), albumen weight (%), Yolk index (YI%), Albumen Index (AI%) and Hough unit (HU). For eight weeks, from February 14 to April 13, 2023. Two hindered fifty-two female quail with age about forty-seven days were divided into six treatments, each including forty-two birds with three replicates (four ten quail of each). The treatments were T1: 0% DPP with mash feed form, T2: 0% DPP with pellet feed form, T3: 0.5% DPP with mash feed form, T4: 0.5% DPP with pellet feed form, T5: 1% DPP with mash feed form and T6: 1% DPP with pellet feed form. The quail were fed a productive diet with 2794 kcal/kg energy and 18.39% crude protein, and similar rearing conditions. Results showed there were significant effects in the percentage of HD, EW., EM, and (FCR) in treatments with DPP and pellet feed form when compared with the other treatments, as well as an improvement in egg quality in treatments with DPP and pellet feed form when compared with the other treatments.

Peningkatan Produksi Melalui Formulasi Pakan Berbasis Potensi Lokal Sebagai Alternatif Pakan Buatan Pada Budidaya Ikan Lele

Doktor Mengabdi (DM) activities develop partnerships in orderto overcome the problem of higher feed prices, which have a small profit or even a loss. This is exacerbated if, during harvest, the price of catfish per kilogram decreases. The urgency needed to solve these problems is then met by training on the formulation and manufacture of self-sufficient feed based on the potential of local ingredients. The activity partners were BUMDES of Labruk Lor Village and the "Mina Agung Mandiri" Fish Farming Group, which was further assisted by the Lumajang District FisheriesService. The results that have been applied to this activity include: 1) socialization with approaches and providing understanding to activity partners; 2) counseling and training to increase knowledge about good and correct fish farming and making fish feed independently by utilizing abundant raw materials in the surrounding area; and 3) The practice or direct application of making fish feed includes flouring the raw materials for making fish feed, mixing all the raw material compositions for making fish feed, and printing using a fish feed pellet printing machine. 4). Evaluation and monitoring of the implementation of activities 5). Evaluating the impact of activities, both the impact on the economy and fish growth, This activity provides farmers with theability to make feed independently and shows an increase in the profit yields of fish farming production by up to 40%. Furthermore, based on the measurements carried out, it showthat the water quality of each partner's pond is still in optimal conditionfor fish growth and does not indicate any diseases that attack the growth and development of the fish being cultivated.

Evaluation and economic analysis of fermented fish viscera silage in diets for tambaqui (Colossoma macropomum) and its effects on the physical quality of pellets, growth performance, health parameters.

The production of silage using fish viscera can be carried out with straightforward methods and permits the exploitation of nutrients that are usually discarded. This process fosters the concept of circular aquaculture. The aim of this study was to evaluate the inclusion of increasing levels of fish viscera silage (VS) on the physical quality of the feed pellets and their effects on their growth performance, health parameters and on economic indices when the experimental extruded feed was offered to tambaqui. A fermented fish VS produced in-house was included in increasing levels on a wet-basis in the formulation of five experimental diets (VS 0%, VS 5%; VS 10%; VS 15%and VS 20%). Juvenile tambaqui (~22.6 g) were stocked in fibreglass tanks of 700 L (n = 4; 21 fish per tank) with a recirculation system and the five experimental diets were attributed in a completely randomized design. The fish were fed with the experimental diets (to apparent satiation) for 13 weeks. At the end of the trial, no significant differences were observed for production performance. Fish fed with the highest inclusion level of VS presented the highest concentration of plasma cholesterol, but this was still within acceptable values for this species. The inclusion of fish VS in diets for juvenile tambaqui reduced the activity of the plasma ALT enzyme, confirming normal liver function. Extruded feed containing fish VS had a production cost of US$ 0.95 per kg, which does not significantly impact the economic indices. Up to 20% of fish VS can be included in the extruded feed formulation for juvenile tambaqui without impairing growth performance or affecting health parameters.

Morphological and structural analysis of Penaeus vannamei mandibles and an attempt at real-time cannibalism monitoring based on passive acoustics

Cannibalism is a significant factor contributing to individual disability, mortality, and reduced shrimp production in commercial culture. The primary challenge of controlling cannibalism is the real-time and efficient monitoring of its occurrence. Here, we simultaneously captured high-speed video and feeding acoustics to match sound signals to feeding behaviors in Penaeus vannamei. Building upon a feeding acoustics signal acquisition system, passive acoustic monitoring (PAM) was utilized to detect differences in the acoustic signals produced when shrimps fed on broken feed, pellet feed, and meat fragments of P. vannamei (cannibalism). The morphological and structural characteristics of P. vannamei mandibles were analyzed using micro-CT, nano-indentation, and Raman testing. The main findings were: (1) Feeding on meat fragments resulted in a distinct high-frequency impulse train signal that may serve as an effective indicator for monitoring cannibalistic behavior during culture. (2) Shrimps produced similar and stable acoustic signals while consuming pellet feed, broken feed, or meat fragments; however, there were significant differences in the numbers of generated pulses (P < 0.05), with broken feed < pellet feed < meat fragments. (3) The mandibles consisted of thin anterior incisors and flat thick posterior molar processes, both with stratified structures; the mandibles exhibited greater elastic modulus and hardness values in their outer layers than inner layers, and calcium phosphate deposits were present in both incisors and molar processes. The collisions between incisors showed patterns that were highly synchronized with the acoustic feeding signals. This study has expanded research on passive acoustics monitoring in crustaceans and provided crucial data for the development of precious feeding technology in crustaceans.

Evaluating the growth performance of all male sex reversal and mixed ser tilapia (Oreochromis niloticus) cultured in earthen ponds in Binh Phuo province, Vietnam

The study was conducted to evaluate the growth performance, survival rate and yield of all male sex reversed and mixed sex Nile tilapia (Oreochromis niloticus) cultured in earthen ponds for 180 days. The reversed sex and mixed sex fingerlings (mean weight 7.43 ± 0.35 g) was randomly stocked in six earthen ponds (1,000 m2/pond). The stocking density maintained was 5 fish/m2. The stocked fish were fed a commercial pellet feed containing 35% crude protein. The feeding rate was adjusted according the size of fish, 5% at the beginning to 3% at harvest. Water environment parameters including dissolved oxygen (DO) (4.3 ± 0.8 mg/L), temperature (30 ± 0.7°C), NH3 (0.18 ± 0.2 mg/L), and pH (6.9 ± 0.5) were always within the appropriate range for the normal growth and development of tilapia. The growth rate of sex reversed tilapia was significantly higher (P &lt; 0.05) than that of mixed tilapia throughout the experiment. The harvest weight and length of reversed sex tilapia were 410.5 ± 5.15 g and 25.48 ± 0.48 cm, respectively, and were significantly higher than that of mixed sex tilapia (P &lt; 0.05). The survival rates and feed conversion ratio (FCR) of mono and mixed sex were 90.1% and 89.9%, respectively, but no significant differences were observed (P &gt; 0.05). The relationship of fish lengths and weights expressed by power function revealed that the slope of the length weight regression lines was normal for reversed sex (2.72) and mixed sex Tilapia (2.93) with the high correlation coefficient (&gt; 0.9). The findings of this study demonstrate that reversed sex tilapia has better growth performance compared to mixed sex tilapia. Therefore, reversed sex fingerlings should be used in commercial farming to increase tilapia production.

Biochemical characterization of purified phytase produced from Aspergillus awamori AFE1 associated with the gastrointestinal tract of longhorn beetle (Cerambycidae latreille)

ABSTRACT The need for industrially and biotechnologically significant enzymes, such as phytase, is expanding daily as a result of the increased use of these enzymes in a variety of operations, including the manufacture of food, animal feed, and poultry feed. This study sought to characterize purified phytase from A. awamori AFE1 isolated from longhorn beetle for its prospect in industrial applications. Ammonium sulfate precipitation, ion-exchange chromatography, and gel-filtration chromatography were used to purify the crude enzyme obtained from submerged fermentation using phytase-producing media, and its physicochemical characteristics were examined. The homogenous 46.8-kDa phytase showed an 8.1-fold purification and 40.7% recovery. At 70 C and pH 7, the optimum phytase activity was noted. At acidic pH 4–6 and alkaline pH 8–10, it likewise demonstrated relative activity of 88–95% and 67–88%, respectively. It showed 67–70% residual activity between 30 and 70 C after 40 min, and 68–94% residual activity between pH 2 and 12 after 2 h. The presence of Hg+, Mg2+, and Al3+ significantly decreased the enzymatic activity, whereas Ca2+ and Cu2+ enhanced it. Ascorbic acid increased the activity of the purified enzyme, whereas ethylenediaminetetraacetic acid (EDTA) and mercaptoethanol inhibited it. The calculated values for Km and Vmax were 55.4 mM and1.99 μmol/min/mL respectively. A. awamori phytase, which was isolated from a new source, showed unique and remarkable qualities that may find use in industrial operations such as feed pelleting and food processing.