Physical Quality Of Feed Research Articles

Effect of Soybean Meal Substitution Using Raintree (Samanea saman) Seed Meal on the Physical Quality of Feed and Growth Performance of the Juvenile White Shrimp, Litopenaeus vannamei

Effect of Soybean Meal Substitution Using Raintree (Samanea saman) Seed Meal on the Physical Quality of Feed and Growth Performance of the Juvenile White Shrimp, Litopenaeus vannamei

Effects of a novel bacteria meal (FeedKind®) on the physical properties of extrudates

The development of fishmeal (FM) alternatives for feed in aquaculture is essential for sustainable and economic fish farming. A study was undertaken to evaluate the potential of a novel bacteria meal (FeedKind® (FK)) as fishmeal substitute. There are significant differences between fishmeal and FeedKind® in viscosity, water absorption, water-soluble protein, oil absorption and other physicochemical properties, which in turn affects the physical quality of feed. Increasing FK content will enhance the pellet durability (P < 0.05) and the expansion (P < 0.01), and decrease the oil leakage (P < 0.05) of the extruded feed pellets. This indicates that FK can be used as a feasible substitute for FM to improve the physical qualities of low-starch floating extrudates. The optimal lower moisture content (24.3%−24.9%) and temperature (127.6 ℃−136.7 ℃) requirement in extrusion after FM is replaced by FK is conducive to reducing the consumption of water and electric energy in the drying process, which contributes to the low carbon emissions and sustainable production of fish feed.

The Effect of Fermentation on Increasing the Physico-Chemical Quality of Fish Feed Based on Food Waste

Fish feed is the crucial aspect of aquaculture activities, 70% of production costs are spent on feed availability. However, the high price of commercial feed causes a decrease in farmers' profits, so a solution is needed to reduce feed costs. Food waste has a good potential to be used as a fish feed material. The fermentation of food waste should improve its quality and ensure that food waste is safe to use as feed material. As a result of various tests of Proximate, FTIR, SEM, and Physical Quality test it has been shown that the fermentation process can significantly improve the nutritional quality of food waste without changing the functional groups and the reduction of the particle size after the fermentation process is also capable to improve the physical quality of feed. We conclude that the fermentation process is the best method of improving the physical and chemical quality of food waste and the addition of fermented food waste meal to feed did not negatively affect the physical quality of feed produced.

The use of tunicate (Ciona intestinalis) as a sustainable protein source in fish feed – Effects on the extrusion process, physical pellet quality and microstructure

The aim of this research was to study the effect of the replacement of fishmeal (FM) or soy protein concentrate (SPC) by tunicate meal (Ciona intestinalis) on the extrusion process, physical pellet quality, pellet expansion, and microstructure. The experiment was based on a 3-component simplex-centroid mixture design. Models with R2 in the range of 0.574–0.999 (P = 0.03 to < 0.0001) were established for specific mechanical energy (SME), temperature behind extruder die (Tdie), apparent dough viscosity in the extruder die (Vdie), pellet hardness, durability, expansion, and microstructure parameters. Increase in SME and Tdie were mainly explained by the reduced lipid content in the feed mix due to the replacement of FM with tunicate or SPC. Reduced Vdie was mainly an effect of increased tunicate level and with the lowest value found for the pure tunicate blend. There was an increase in volumetric expansion and open porosity by replacement of SPC with tunicate, explained by this decrease in Vdie. Reduced hardness and durability were found for blends high in SPC due to incomplete plasticisation. Extrudate expansion, fat adsorption capacity and leakage were explained by the extrudate microstructure measured by X-ray microtomography. Within the boundary of the chosen design, 64% of the FM can be replaced by tunicate meal without compromising physical feed quality. Due to its viscosity behaviour, tunicate meal can improve pellet expansion and fat absorption capacity of extruded feed.

Physical feed quality and starch content causes a biological response in Atlantic salmon (Salmo salar L)

The aim of this study was to investigate the effect of starch content and pellet physical quality on the biological response in Atlantic salmon. Salmon feeds with a large variation in physical quality were produced by the adjustment of dietary starch inclusion (92 g kg−1 or 64 g kg−1), preconditioner oil (0.0 or 11.0 kg h−1), extruder moisture addition (13.5 or 27 kg h−1) and drying temperature (38 °C or 70 °C). The variables impacted physical quality for the 12 feed codes and with hardness S (standing) and Durability measured in the range of 39–212 N and 39–94 %, respectively. Gently dried feed (38 °C) was harder and more durable than conventionally dried (70 °C). This could be explained by the phase transition theory and drying in the mobile rubbery phase above the glass transition temperature (Tg) for the gently dried feed codes. All feed codes were evaluated in Atlantic salmon performance and digestibility trials. There was a significant difference between the codes for weight gain (%; P < 0.001), specific and thermal growth rate (P < 0.01) and protein efficiency ratio (P < 0.01). Growth was negatively associated with increased starch content, hardness and durability parameters and reduced solubility, fat content and gross energy. The most important physical properties affecting growth performance were Hardness S, Durability and Doris dust, parameters that may represent feed hydration- and dissolution rates. This study documents that the impact of pellet physical quality should be considered when evaluating the results from biological fish trials.

Comparison of new and conventional processing methods for their effects on physical properties of fish feed

At present, aquafeed is made mainly by low-moisture extrusion cooking. To further improve feed quality, we developed a new process featuring high-moisture extrusion with a twin-screw extruder and a specially designed cooling die. In this study, aquafeed was made with two mash formulations (with or without wheat flour) by low moisture (conventional) or high moisture (new) extrusion under the same temperature (138 °C). Fresh and/or dried extrudates were evaluated for visual appearance, physical quality (water absorption and hardness with soaking time, bulk density, pellet durability, water stability and oil absorption capacity), chemical composition and degree of starch gelatinization. Results show that processing methods, feed formulation and post-extrusion drying all had significant effects on the visual appearance and physical quality of feed. The new feed (NF) was less expanded and less porous than conventional feed (CF), leading to significant reduction in oil absorption capacity, about 85 % of CF.Upon contact with water, fresh and dried CF absorbed water quickly and disintegrated easily, while NF absorbed water slowly and maintained a soft texture (around 50 g/mm2, comparable to fish fillet texture) even after 24 h of soaking. Dry matter loss from NF was significantly less than CF, after 6 h shaking in water. Due to its compact texture, NF had higher pellet durability than CF, with a bulk density greater than 1 g/cm3. Addition of wheat flour to the mash made CF more porous, harder in texture and less water stable but exerted a limited effect on NF. Therefore, the new process produced aquafeed that was soft in texture, durable, and extremely water-stable, while making addition of starch or other binder unnecessary. Although an increase in drying cost for NF is expected, the new method offers a good alternative to produce specialty feed and a promising strategy to reduce water pollution issues associated with aquaculture.

The effect of the level of mixer-added water and mash conditioning temperature on parameters monitored during pelleting and phytase and xylanase thermostability

Exogenous enzymes have been used in broiler and swine rations to improve nutrient utilization and reduce feed costs, both of which improved the efficiencies of live production. Feed manufacturers have also utilized practices, such as warm mash conditioning temperatures (CT) and the addition of moisture at the mixer or mash conditioning chamber, to maintain adequate physical feed quality. While the impact of warm conditioning practices on enzyme thermostability had been well described, the impact of mixer-added water (MAW) on enzyme thermostability was scarcely investigated in previous literature. The present experiment intended to investigate the interaction of three mash CT and three levels of MAW on the thermostability of a phytase and xylanase mixer-added enzyme within a swine gestation diet in a 3 × 3 factorial randomized complete block design. The mash CT included 80, 86, and 92 °C and the levels of MAW included 0, 10, and 20 g/kg. Parameters monitored during the pelleting process included pellet durability index (PDI), pellet mill energy consumption (PMEC), and the change in temperature between hot pellets and conditioned mash (Δ T). Conditioning mash at 92 °C resulted in a 22.5 percentage-point reduction in phytase recovery in conditioned mash and a 70.1 percentage-point reduction in phytase recovery in pellets when compared to diets pelleted at 80 °C (P < 0.01). The xylanase, however, was not affected by mash CT. Phytase and xylanase recovery in pellets was not affected by the level of MAW. As PDI and PMEC increased, phytase recovery in pellets relative to unconditioned mash decreased (P < 0.01). As Δ T increased, phytase recovery in pellets relative to unconditioned mash increased (P < 0.01). Xylanase denaturation was poorly described by the parameters monitored during pelleting, likely because it was minimally denatured during pelleting. A robust multiple regression model was generated to predict phytase activity in pellets relative to unconditioned mash (R2 = 0.95; P < 0.01) when the controlled factors and monitored parameters were combined in a predictive model. In conclusion, the primary site of enzyme denaturation in a pilot scale pellet mill was the pellet mill die and MAW did not affect enzyme recovery.

Efecto del transporte y de un sistema automático de alimentación sobre la calidad física y química de los piensos granulados para pollos de engorde

Evaluamos los efectos del transporte y del sistema de alimentación automática sobre las características químicas y físicas de los alimentos peletizados para pollos de engorde en la etapa final de producción. Las muestras se recogieron en dos días y en dos gallineros diferentes, ambos equipados con el mismo tipo de sistema automático de alimentación de placas. Las muestras se recolectaron a la salida del secador de peletización (PEL), a la salida del camión a granel (CAM) y a los 0 (LIN0), 50 (LIN50) y 100 (LIN100) metros de la línea de alimentación, para el análisis de actividad del agua, materia seca, materia mineral, proteína bruta, MEP (Método de Evaluación de Pelletización, Embrapa), IDB (Índice de Durabilidad del Bolita) y porcentajes gruesos y finos. Empleamos un diseño de bloques completos al azar con cinco tratamientos (puntos de recolección) y cinco repeticiones. Los resultados indican que la calidad física de la alimentación se vio afectada negativamente por los factores involucrados en el proceso de transporte, con mayor actividad de agua (P

Water-soluble protein level in fishmeal affects extrusion behaviour, phase transitions and physical quality of feed

The aim of this research was to investigate the effect of water-soluble protein (WSP) as a plasticizer in the fish feed extrusion process and the impact on physical pellet quality. A three-factor central composite design was used to study the influence of the variables WSP in the feed mix, and steam and water addition in the extruder. Regression models with r2 in the range of 0.862–0.976 (P < 0.001) were established for specific mechanical energy (SME), pellet hardness, cutting strength, sectional expansion index, length, bulk density, oil adsorption capacity and extrudate flow-starting temperature (Tf). Addition of WSP had a positive effect on SME and improved the physical pellet quality, while moisture had the opposite effect. Expansion parameters showed a complex relationship and were influenced by all the studied process variables. Increase in WSP and moisture content had a comparable effect on Tf reduction. This opens up the possibility to obtain a satisfactory ‘cook’ at reduced moisture level with a potential for significant reduction of the energy consumption during drying of the extrudate. Overall conclusion from the experiment is that WSP can be used as a processing aid for the fish feed industry, serving multiple purposes as nutrient, plasticizer and binder in extruded fish feed.

Standardized method for the Holmen pellet tester (NHP100) as a tool for evaluating the physical quality of fish feed

The fish feed production industry requires reliable methods measuring the physical quality of feed before it is being released to the customer. The Holmen pellet tester (NHP 100) could be adapted for this purpose, but the special characteristics of fish feed require particular care during testing. The aim of the study was to determine the standardized conditions for using the Holmen tester as a tool measuring the durability of fish feed. Screening tests were performed on commercial fish feed samples to assess the effects of temperature, pressure and cleaning the instrument between runs. The operating pressure was found to be the most important factor that can influence the results. The temperature of the operating air can also alter the results; increased temperatures can cause oil to melt and leak from the pellets. Cleaning the instrument between analyses can also affect the results. This study shows that when these factors are maintained at a standardized level, the Holmen pellet tester is a valuable tool for assessing the physical quality of fish feed giving additional information on the quality of feed pellets compared to other durability tests like DORIS.

Effects of dietary moisture content of extruded diets on physical feed quality and nutritional response in Atlantic salmon (Salmo salar)

Feeds in modern aquaculture must be of high physical quality to withstand mechanical impacts. However, physical quality of feed has been shown to affect nutritional responses. In this study, different physical feed qualities were created using different drying time. Effects on physical feed quality, feed intake, nutrient digestibility and growth in Atlantic salmon were investigated. Different drying times of four commercial-like diets resulted in dry matter contents of 95.9%, 94.1%, 92.3% and 90.8%. A fifth diet containing 70% dry matter was made by soaking pellets. Triplicate groups of Atlantic salmon (961 ± 12.1 g ind−1, mean ± SEM) were first fed ad libitum and thereafter a restricted ration. The diets differed significantly in bulk density, DORIS durability, hardness, water stability after 60 and 120 min, but not in water stability after 240 min. Feed intake and growth were not affected by physical quality of the dry diets, whereas soaking had a positive effect on feed intake. Restricted compared with ad libitum feeding increased nutrient digestibility, but digestibility was not affected by varying drying time among diets. However, soaking resulted in slightly reduced digestibility of starch. Most methods used to analyse physical quality did not correlate with feed intake and growth; only long-term water stability affected feed intake.

Influence of type of raw material on fishmeal physicochemical properties, the extrusion process, starch gelatinization and physical quality of fish feed

The aim of this study was to investigate the impact of two types of fish raw material on fishmeal (FM) physicochemical properties, specific mechanical energy, starch gelatinization and physical feed quality. Eleven feed mixes based on six independent FMs from herring (FMH) and five from sand eel (FMSE) were extruded according to standardized conditions. Type of fish raw material influenced FM physicochemical properties and had significant impact on starch gelatinization and pellet hardness. Multivariate models were established based on partial least squares regression (R2 = 0.637–0.999). Improved degree of starch gelatinization was associated with increased degree of protein hydrolysis (P = 0.011) and by replacement of FMH with FMSE in the feed mix (P = 0.012). A large span in pellet hardness was observed (4.9–94.1 N). Improved hardness was associated with decreased level of non-soluble protein (P < 0.001) and by replacement of FMSE with FMH (P < 0.001). For FMSE, improved hardness was associated with decreased level of non-soluble protein (P < 0.001) and increased degree of protein hydrolysis (P = 0.002), compressed bulk density (P = 0.039) and dust fraction (P = 0.001). The underlying physical and chemical mechanisms are discussed. The study documents differences in technical quality of FM produced from herring and sand eel with significant impact on fish feed extrusion and pellet quality.

Immunolocalization of succinate dehydrogenase in the esophagus epithelium of domesticated mammals.

Using immunohistochemistry and transmission electron microscopy (TEM), the esophagus epithelia of seven domesticated mammals (horse, cattle, goat, pig, dog, laboratory rat, cat) of three nutrition groups (herbivorous, omnivorous, carnivorous) were studied to get first information about energy generation, as demonstrated by succinate dehydrogenase (SDH) activities. Distinct reaction intensities could be observed in all esophageal cell layers of the different species studied reflecting moderate to strong metabolic activities. The generally strong staining in the stratum basale indicated that new cells are continuously produced. The latter feature was confirmed by a thick, and in the horse generally highly active stratum spinosum. Only in the pig, reaction intensity variations occurred, obviously related to differences in physical feed quality or restricted feed allocation. The immunohistochemical results were corroborated by the presence of intact mitochondria in the esophageal cells of all species and nutrition types studied, except for the horse. Possible relationships between SDH reaction intensities and feed structure, mass or consistency are discussed.

A review of the effects of ingredient composition and processing conditions on the physical qualities of extruded high-energy fish feed as measured by prevailing methods

Feed comprises the biggest cost in intensive fish farming and the quality of feed is therefore important. A vast body of research has been carried out in order to investigate nutritional quality of alternative ingredients. Effects of ingredients on physical quality are seldom included in these investigations. Physical quality of feed varies with ingredient composition and processing condition and may interfere with feed intake, nutrient digestibility and therefore growth performance of the fish. In this review, physical quality of extruded, high energy feed, and how ingredient composition and processing conditions affect the quality will be addressed. Various pellet properties will be discussed and methods used to evaluate physical quality will be reviewed.

Analysis of pellet degradation of extruded high energy fish feeds with different physical qualities in a pneumatic feeding system

The aim of the present study was to investigate degradation of three commercial high energy extruded salmonid feeds, differing in physical quality, during pneumatic conveying in a feeding device at different airspeeds (25, 30 and 35ms−1) and feeding rates (9, 18 and 36kgmin−1). The physical quality of the feeds, with a diameter of 12mm, was measured as existing quality, DORIS value, hardness and durability index. Significant differences in the formation of small particles among the feeds were observed during pneumatic conveying. Increasing air speed (ms−1) increased the formation of fractures (particle size 2.4–10mm) and fines (particle size<2.4mm). Increasing the feeding rate (kgmin−1) had the opposite effect, causing a reduction in formation of fracture and fines. Despite the significant differences in physical quality among the diets, no good correlations were found between physical quality parameters and pellet degradation during pneumatic conveying. DORIS value, hardness and durability index could therefore not be used to predict the degradation of pellets during pneumatic conveying.The overall conclusion from the experiment was that the three feeds varied in degradation pattern during pneumatic conveying, and the pellet degradation was highest at high airspeed and at low feeding rate. None of the measured variables for physical feed quality could be used to predict the pellet degradation pattern in the feeding system.

Pea protein concentrate substituting fish meal or soybean meal in diets for Atlantic salmon (Salmo salar)—Effect on growth performance, nutrient digestibility, carcass composition, gut health, and physical feed quality

The effect of pea protein concentrate in diets for Atlantic salmon on growth performance, nutrient digestibility, carcass composition, blood chemistry, histology of the gastro-intestinal tract (GIT), and physical feed quality was investigated. A 12-week study was conducted using triplicate groups of Atlantic salmon with 0.16 kg initial weight kept in seawater. The dietary treatments consisted of one control diet based on high-quality fish meal (FM diet), one control diet containing 200 g kg−1 soybean meal (SBM diet), and two experimental diets containing 200 g kg−1 pea protein concentrate with either 350 or 500 g kg−1 crude protein (PPC 35% CP and PPC 50% CP diet), substituting for fish meal protein. There were no significant differences among dietary treatments for weight gain or feed intake, but there was a tendency (P<0.07) toward a lower feed conversion ratio in fish fed the PPC 50% CP diet. There were no differences in the digestibility of protein, fat, starch and most essential amino acids between the fish fed the FM and the PPC 35% CP or PPC 50% CP diets, but the PPC diets gave lower energy digestibility. The SBM diet gave reduced digestibility for protein, fat, starch, essential amino acids, and energy compared with the FM and the PPC diets. Also, feeding the PPC diets had no effect on body composition, while the SBM diet reduced (P<0.05) the content of carcass fat and energy compared with the FM diet. Feeding the PPC diets did not induce morphological changes in the intestine, or affect the size of the GIT. Brush border maltase activity and fecal trypsin activity were unaffected. Feeding the SBM diet increased the size of the stomach, decreased the size of the distal intestine (DI), induced morphological changes in the DI, reduced brush border maltase activity, and increased fecal trypsin activity compared with the FM and PPC diets. In conclusion, pea protein concentrate was shown to be a promising new protein ingredient for salmonids and could replace 20% of high-quality fish meal protein in the feed without any adverse effect on growth performance, carcass composition or histology of the DI.

Soybean meal improves the physical quality of extruded fish feed

The study was designed to investigate effects of processing of soybean meal on physical quality of extruded fish feed. Three diets were produced; one fish meal (FM) based control diet, and two diets with 40% amino acids from FM replaced by defatted, toasted soybean meal (SBM) or defatted, untoasted soybean meal (white flakes, WF). The diets were extruded under steady state standardized conditions. The WF diet was also extruded with an alternative screw-configuration and reduced screw revolution (RPM) generating a specific mechanical energy (SME) during the production similar to the FM and SBM diets. The WF feed from the first and second production is thus denoted as the WF1 diet and the WF2 diet, respectively. Partial replacement of FM with either SBM or WF improved the physical quality of feed in terms of breaking force and durability, bulk density was elevated and radial expansion reduced. Inclusion of WF increased the motor load, die pressure and SME of the WF1 diet compared to the FM and SBM diets, resulting in significantly longer pellets and higher bulk density. Extrusion of the WF2 diet with a less shearing screw configuration in combination with reduced screw rotation gave SME comparable to the energy consumption used during the production of the FM and SBM diets. The new processing conditions caused a significant reduction in length and diameter, and hence increased bulk density. Breaking force corrected for the diameter of the pellet was significantly higher for the WF2 diet produced with lower shear and screw rotation compared to the other three feeds produced under the same extruder conditions. The overall conclusion from the experiment was that durability and breaking force of extruded fish feed was significantly improved by inclusion of soy, regardless of previous heat treatment of this feed ingredient.