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Whey, obtained from cheese manufacturing, has a significant environmental impact due to its organic load and volume produced. Therefore, validating technologies that allow its valorization due to its content of ingredients of high nutritional or functional value becomes relevant for the dairy industry. Microparticulate whey protein (MWP) has been used to produce cheeses and has the potential to improve process performance. We seek to develop and optimize the characteristics of a MWP to be used to make white cheese. For this, factors such as temperature, from 73 to 93°C, and retention time from 3 to 17 min of the heat treatment were evaluated. We assessed zeta potential, particle size, color, protein retention coefficient, and cheese yield as response variables using a response surface design with 14 experiments. Optimum conditions were 93°C for 5.4 min retention. In the white cheese production, two inclusion percentages were tested: 3 and 5% (w/w); and the impact on characteristics like yield, protein retention, and texture was evaluated with respect to a control cheese that was not added with MWP. We found that 3% inclusion is more suitable because it keeps textural characteristics closer to traditional cheese. The MWPs add value to whey and cheese by improving performance and enabling the retention of proteins of high biological and nutritional value.

Whey is a liquid by-product obtained by cheese elaboration, which is not completely used due to the large quantities produced. As a result, the whey is poured into rivers and soils and becomes a pollutant agent. The valorization of acid whey using membrane clarification was evaluated, where the effect of temperature and membrane cut-off were studied using acid whey. Permeability was three times higher at 70°C than 50°C (163.2±11.1 y 62.4±9.2 L/m2 .h, respectively) for membranes with a cut-off of 0.2 µm. Furthermore, the permeate flux for this cut-off was three, six and ten times higher compared with the cut-off of 300, 150 y 50 kDa at 70°C, respectively. The clarification stage was scaled-up with 0.2 µm membranes, achieving about 22 L of whey filtered for Batch mode until a volume reduction factor (VRF) of 5 with protein retention of 68%. In Fed-Batch mode, the retention of protein was 61%, but the filtration could be carried out for longer, reducing fouling and filtering almost the double of the quantity of whey compared with Batch mode. In all cases, the turbidity of permeates was lower than 12 NTU (reduction >99%), regardless of whey turbidity whose values might be superior to 12,000 NTU. [ABSTRACT FROM AUTHOR]

Prawns (Macrobrachiumrosenbergii) is one of the freshwater shrimp species native to Indonesia. Shrimp prawns are the most popular of all freshwater shrimp because of its large size and has a high economic value in both domestic market and abroad. Problems commonly encountered in the cultivation of prawns currently includes several factors such as water quality, disease and feed. Efforts that can be done is by feeding in sufficient quantity and quality and not excessive is a very decisive factor. Technical constraints on the level of farmers are limited in supply mains quality. Therefore, efforts are needed to tackle these problems by managing the stock of prawns parents. This study aims to determine the addition of cod liver oil on a commercial feed can increase protein retention and energy retention prawns (Macrobrachium rosenbergii). This research was carried out experimentally with a completely randomized design (CRD). The treatments were given a dose of cod liver oil 0% (control), and the treatment 1-4 using a 3% increase each treatment dose. Analysis of data using ANOVA followed by Duncan test. Based on the research results giving cod liver oil on a commercial feed effect on increasing protein retention and energy retention of lobster meat. Retention of the best protein found in 4 treatments with a dose of 12%, while the retention of the best energy contained in the second treatment with a dose of 6%.

Litopenaeus vannamei is a leading commodity whose economic value. Targets of vannamei's production increasing every year. One of important factor in the success of shrimp farming is feed. Research about feed fish directed to the creation of feed fish whose economical and safe for the environment, therefore is required an efforts to provide alternative feed through feed supplement. One of the material that can be supplemented in feed is chitosan. Chitosan can increase the specific growth rate and protein retention of vannamei. This study aims to determine the effect of chitosan supplementation in commercial feed for specific growth rate and protein retention of Litopenaeus vannamei. The research method used was completely randomized design (RAL) and performed with five treatments chitosan supplementation (0%, 1%, 2%, 3% dan 4%) experimental animal used was ten shrimps as five replication in each treatment. The main parameters were observed are specific growth rate and protein retention of vaname. Supporting parameters were observed is water quality. The results showed that chitosan supplementation in commercial feed for 30 days of maintenance give an effect on the specific growth rate and protein retention of vaname. The highest specific growth rate was obtained in treatment with 4% chitosan supplementation that not significantly different with treatment 3% chitosan supplementation. Protein retention was incresed in treatment with 4% chitosan supplementation that not significantly different with treatment 3% chitosan supplementation.

The aim of the current trial was to test whether leucine affected growth and accretion including test any effects on leucine upon stress. Quadruplicate tanks each containing 50 Atlantic salmon (Salmo salar) (mean start body weight of 524 ± 28 g) were fed diets containing 27.3, 30.0, 35.0 and 41.0 g leucine/kg diet for 74 days. Two tanks per dietary group were exposed to a stressor (5 min chasing) three days a week to test whether enriched leucine diet aid coping with chronic stress, while two tanks per dietary groups were left unstressed. The stressed fish consumed less feed and grew less than the unstressed fish, irrespective of diet. Leucine inclusion did not affect protein accretion, but leucine retention declined with increasing dietary leucine in both stressed and unstressed fish. No difference between the stressed or unstressed fish was present. Leucine did not affect relative liver size, but unstressed fish had slightly higher relative liver size compared with stressed fish (p = 0.05). Free leucine in the muscle and liver was not affected by dietary leucine, but unstressed fish had higher concentration of valine and isoleucine in the muscle compared with the stressed fish. Muscle of fish fed elevated leucine had lower mRNA expression of murf1 (p = 0.037) and higher expression of ppara (p = 0.012). Muscle of stressed fish had higher expression of the oxydative genes mnsod (p = 0.049) and catalase (p = 0.037) compared with the fish left unstressed, while in liver, there were no differences of expression of any of the genes tested. In conclusion, diets enriched in leucine had minor effects and neither protein accretion nor growth was affected in either stressed or unstressed fish. [ABSTRACT FROM AUTHOR]

This study with juvenile rainbow trout evaluated the effects of dietary exposure to deoxynivalenol (DON) at industrially relevant doses (up to 1.6 mg/kg) on growth performance, the liver, and the gastrointestinal tract. Fifteen groups of 30 fish each were given one of five dietary treatments in triplicate: (1) control diet (CON; DON < 100 µg/kg feed), (2) naturally DON-contaminated diet (ND1) with a DON content of 700 µg/kg in the feed, (3) ND2 with a DON content of 1200 µg/kg feed, (4) a pure DON-contaminated diet (PD1) with 800 µg/kg of DON in the feed, and (5) PD2 with DON at a concentration of 1600 µg/kg in the feed. The feeding trial lasted eight weeks: six weeks of restrictive feeding followed by two weeks of ad libitum feeding. Exposure to DON during restrictive feeding for six weeks did not affect the growth performance of trout but did lead to a reduction in retained protein in fish fed with higher doses of DON in the ND2 and PD2 groups. During the two following weeks of ad libitum feeding, feed intake was similar among all groups, but body weight gain was lower in the ND2 and PD2 groups and feed efficiency was higher in PD2 (week 8). Histopathological assessment revealed liver damage, including altered nuclear characteristics and haemorrhages, in groups fed higher doses of natural DON (ND2) after just one week of restrictive feeding. Liver damage (necrosis and haemorrhage presence in ND2) was alleviated over time (week 6) but was again aggravated after ad libitum exposure (week 8). In contrast, gastrointestinal tract damage was generally mild with only a few histopathological alterations, and the absence of an inflammatory cytokine response was demonstrated by PCR at week 8. In conclusion, ad libitum dietary exposure of rainbow trout to either natural or pure DON resulted in reduced growth (dose-dependent), while restrictive exposure revealed time-dependent effects of natural DON in terms of liver damage.

A two‐phase feeding trial was conducted to estimate the dietary histidine requirement of juvenile and post‐juvenile rainbow trout for maximum growth and protein retention. Twelve isonitrogenous experimental diets were formulated where diet 1 was an 8% fishmeal basal diet having 0.5% histidine. Histidine was added to diets 2–6 to achieve levels of 0.7, 0.9, 1.1, 1.3 and 1.5% histidine respectively. Diets 7–12 were identical to diets 1–6 except for pellet size. In trial 1, fish (4 g) were fed test diets 1–6, and in trial 2, fish (40 g) were fed diets 7–12, to four replicate tanks per diet for 12 weeks. A nutrient digestibility trial was also conducted with trout from trial 2. Growth performance and feed utilization were not significantly influenced by dietary histidine supplementation above the basal diet level in either rainbow trout juveniles or post‐juveniles. Supplementation of histidine significantly increased protein and histidine digestibility, and it was lowest in the basal diet group. The highest histidine retention was in the lowest dietary histidine treatment group, and histidine retention progressively decreased at each increase in dietary histidine. In post‐juvenile trout, the same pattern was observed except that for the two lowest histidine levels, retention was similar and high. Finally, considering the overall growth and nutrient retention performances, the dietary histidine requirement is relatively higher in post‐juvenile trout (>0.6%) rather than juvenile trout (0.6%) under the present experimental conditions. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effects of lysine and histidine supplementation on growth performance, gene expression, blood parameters and quality of the fillet in Nile tilapia, Oreochromis niloticus (n = 192; 136.14 ± 2.32 g). Fish were distributed into four groups and fed a control diet without lysine and histidine supplementation (CON), supplemented with lysine (LYS), histidine (HIS) or lysine and histidine (LYS + HIS) and fed until apparent satiety for 90 days. Growth performance increased significantly in fish fed diet LYS + HIS (p <.05). The fillet body weight gain and fillet yield increased by 26.61% and 2.74% unit, respectively, compared to fish fed CON diet (p <.001). Compared to the control group, fish fed diets showed decreased whole‐body lipid and plasmatic triglycerides coupled to increased mRNA levels of MyoD and myogenin in the skeletal muscle and higher texture attributes of fillets (p <.05). There was a substantial negative correlation between body lipids and hardness of fillets. Overall, the combined supplementation of lysine and histidine optimizes growth performance, expression of muscle growth‐related genes and flesh quality attributes in grow‐out Nile tilapia. [ABSTRACT FROM AUTHOR]

Current parenteral containers used for the storage and delivery of protein-based drugs, contain silicone oil which may seep into the protein solution and can result in adsorption, aggregation and denaturation of the protein. Tightly adherent surface coatings prepared by radio frequency glow-discharge (RFGD) plasma polymerization are described in this paper. Using this robust technique, methacrylic acid (MA) (hydrophilic), hexamethyldisiloxane (HMDSO) (hydrophobic), tetraglyme (TG) (hydrophilic) were plasma polymerized onto glass. In addition, HMDSO and MA were copolymerized to create a plasma polymerized HMDSO-MA (hydrophobic) surface. Untreated glass and glass dip-coated in PDMS were used as controls. TG and MA plasma coatings adsorbed the least amount of protein in all pH conditions. Interestingly HMDSO-MA retained significantly lesser protein compared to HMDSO and dip-coated PDMS samples. In the presence of Polysorbate 80 (PS80) all plasma polymerized coatings adsorbed and retained negligible amounts of protein, compared to controls. Furthermore, the peak glide force of plasma coated syringes did not significantly increase compared to syringes without plasma coating. Due to the versatility of RFGD plasma, this process is scalable and could potentially be used for the treatment of hypodermic syringes used for the storage and delivery of protein-based therapeutics. [ABSTRACT FROM AUTHOR]

The efficiency of SID Lys utilization (kSID Lys) in gilts and sows during early (days 48 to 52), mid (days 75 to 79), and late gestation (days 103 to 107) was investigated using 88 pregnant females (PIC 1050; 27 gilts, 27 parity 1 sows, 34 parity 2+ sows; 192.96 ± 22.84 kg at days 42 ±1 of gestation) and whole body nitrogen (N) retention balance studies. Females were assigned to 1 of 4 SID Lys levels ranging from 40% to 70% of the daily SID Lys requirements above maintenance for a parity 1 sow according to the NRC (2012) gestating sow model in each gestation period. Experimental diets were isocaloric (3,335 kcal ME/kg) and isoproteic (11.75 % CP) and dietary indispensable AA were set to meet or exceed 100% of AA:Lys ratios. The slope of the linear response to graded SID Lys intake was defined as kSID Lys. With the aim of increasing the accuracy of kSID Lys estimates, gilt data from the current study was combined with gilt data from a previous study conducted at the same facility using 4 SID Lys levels ranging from 60% to 90% of the daily SID Lys requirements above maintenance for gilts according to the NRC (2012) gestating sow model. Whole body Lys retention of the combined gilt data set was assessed with different broken-line and nonlinear models. The kSID Lys was 0.65, 0.38, and 0.52 for early-, mid-, and late-gestation, respectively, in gilts. A linear response to graded SID Lys intake was found in late gestation only in parity 1 and 2+ sows; kSID Lys was determined as 0.44 and 0.52 in late gestation for parity 1 and parity 2+ sows, respectively. There were no differences in kSID Lys in late gestation between parities. For the combined gilt data, the model of best performance (reduced error and greater goodness of fit) was the Hoerl model. Maximum kSID Lys (i.e., g SID Lys retention/g SID Lys intake) in gilts was 0.67, 0.54, and 0.53 in early, mid, and late gestation predicted at 7.2, 9.1, and 13.5 g of SID Lys intake/d, respectively, based on the Hoerl model. Maximum SID Lys retention in gilts was similarly predicted at 8.5, 10.5, and 20.9 g of SID Lys intake per day in early, mid, and late gestation and resultant kSID Lys of 0.61, 0.51, and 0.44, respectively. The findings of this study demonstrate that kSID Lys varies by stage of gestation and SID Lys intake level and that, at least in gilts, a dynamic kSID adjusted for daily intake more adequately reflects biological response and hence allows more precise feeding of pregnant females. [ABSTRACT FROM AUTHOR]

Bariatric surgery may induce protein malabsorption, although data are scarce. This study aims at evaluating dietary protein bioavailability after different bariatric surgeries in rats. Diet-induced obese Wistar rats were operated for vertical sleeve gastrectomy (VSG) or Roux-en-Y gastric bypass (RYGB). The control group was composed of pair-fed, sham-operated rats (Sham). Two weeks after surgery, rats were fed a 15N protein meal. Protein bioavailability was assessed by determination of 15N recovery in the gastrointestinal tract and organs 6 h after the meal. Fractional protein synthesis rate (FSR) was assessed using a flooding dose of 13C valine. Weight loss was the highest in RYGB rats and the lowest in Sham rats. Surprisingly, RYGB (95.6 ± 0.7%) improved protein digestibility (P = 0.045) compared with Sham (93.5 ± 0.5%) and VSG (93.8 ± 0.6%). In contrast, 15N retained in the liver (P = 0.001) and plasma protein (P = 0.037) was lower than in Sham, with a similar trend in muscle (P = 0.052). FSR was little altered by bariatric surgery, except for a decrease in the kidney of RYGB (P = 0.02). The 15N distribution along the small intestinal tissue suggests that dietary nitrogen was considerably retained in the remodeled mucosa of RYGB compared with Sham. This study revealed that in contrast to VSG, RYGB slightly improved protein digestibility but altered peripheral protein bioavailability. This effect may be ascribed to a higher uptake of dietary amino acids by the remodeled intestine. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to determine the efficiency of utilizing SID Lys and Thr for whole-body protein retention (kSIDLys and kSIDThr) in pregnant gilts. In Exp. 1, 45 gilts (158.0 ± 8.0 kg at day 39.4 ± 1 of gestation) in 2 groups were used in a 3-period nitrogen (N)-balance study. Gilts were assigned to 1 of 4 diets set to provide 60, 70, 80, and 90% of predicted daily SID Lys requirement for protein retention (NRC, 2012) in each of early (day 41 to 52, 10.44 g/d), mid- (day 68 to 79, 9.60 g/d), and late gestation (day 96 to 107, 16.04 g/d). Diets contained 3,300 kcal ME/kg and 11.6% CP; given at a rate of 2.13 kg/d in early and mid-gestation and at 2.53 kg/d during late gestation. The 12-d balance period (7-d adaptation; 5-d urine and fecal collection) was based on total urine collection using urinary catheters and determination of fecal N digestibility using indigestible marker. The SID Lys required for whole-body protein retention was estimated using the NRC (2012) model and the predicted Lys content of each gestation pool. Lysine efficiency at each diet Lys level was calculated as the ratio of daily Lys retention and SID Lys intake. The linear and quadratic response in whole-body N and Lys retention and Lys efficiency for each balance period was determined. The kSIDLys was determined from the slope generated by regressing whole-body Lys retention vs. SID Lys intake, with y -intercept set to 0. In Exp. 2, 45 gilts (165.7 ± 13.6 kg at day 39.1 ± 2 of gestation) were assigned to 1 of 4 diets set to provide 60, 70, 80, and 90% of the predicted daily SID Thr requirement for protein retention in each of early (6.46 g/d), mid- (6.05 g/d), and late gestation (9.75 g/d). Animal management, N-balance procedure, data collection and calculation, and statistical analyses were patterned from Exp. 1. In early and mid-gestation, whole-body N retention, as well as Lys and Thr retention, was not affected by the dietary SID Lys and Thr. In late gestation, there was a linear increase (P < 0.001) in whole-body N, Lys and Thr retention. The kSIDLys and kSIDThr in late gestation were determined to be 0.54. The lack of response in whole-body protein retention in early and mid-gestation may in partly reflect excess Lys and Thr intake. Lysine and Thr efficiency calculated at the lowest dietary Lys and Thr was 0.49 and 0.32 in early gestation and 0.61 and 0.52 in mid-gestation, respectively. Based on the available evidence, kSIDLys and kSIDThr do not appear to be constant throughout gestation. [ABSTRACT FROM AUTHOR]

Abstract To further optimize practical diets with respect to IAA requirements, this study was conducted to confirm and refine the tryptophan requirement, which is a potentially limiting AA in our matrix of ingredients. In order to ensure the best information on Trp requirement, our study used wide range of Trp levels and quality of fit of the models for calculating requirement estimates. Twelve iso‑nitrogenous and isoenergetic diets (practical defined ingredients) containing 30% protein and 8% lipid were formulated to meet the nutritional requirement of juvenile Nile tilapia (Oreochromis niloticus) with the exception of tryptophan. A basal diet deficient in tryptophan was assigned to meet all other known nutrient requirements of the Nile tilapia. L-tryptophan was then added to the basal diet at 0.04% increments to produce tryptophan levels ranging from 0.21 to 0.61% of the diet. The diet which supported the best performance of Nile tilapia in previous work, was used as a reference diet. Each diet was fed to three replicate groups of juvenile Nile tilapia (7.9 ± 0.1 g) in a recirculation system for eight weeks. Saturation kinetic model, broken line models with linear or quadratic ascending portions, were used to evaluate dose-response relationships of thermal-unit growth coefficient, apparent net protein retention, tryptophan retention against dietary tryptophan. Akaike weights were calculated and used for model selection in addition to the model's overall R 2. The tryptophan requirement of juvenile Nile tilapia was estimated at 0.31% (0.25–0.37%), 0.33% (0.26–0.39%), 0.25% (0.24–0.25%), 0.27% (0.25–0.31%) of the diet for optimum growth, tryptophan deposition, feed efficiency, and apparent net protein deposition (95% of maximum value), respectively. Highlights • The study was conducted using Nile tilapia to confirm and refine the tryptophan requirement, which is a potentially limiting AA in our matrix of ingredients. • Saturation kinetic model, broken line models with linear or quadratic ascending portions, were used to evaluate dose-response relationships of thermal-unit growth coefficient, apparent net protein retention, tryptophan retention against dietary tryptophan. Akaike weights were calculated and used for model selection in addition to the model's overall R 2. • The tryptophan requirement of juvenile Nile tilapia was estimated at 0.31% (0.25–0.37%), 0.33% (0.26–0.39%), 0.25% (0.24–0.25%), 0.27% (0.25–0.31%) of the diet for optimum growth, tryptophan deposition, feed efficiency and apparent net protein deposition (95% of maximum value), respectively. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the nutritional value of pasta enriched with legume or wheat gluten proteins and dried at varying temperature. A total of four isonitrogenous experimental diets were produced using gluten powder/wheat semolina (6/94, g/g) pasta and faba bean flour/wheat semolina (35/65, g/g) pasta dried at either 55°C (GLT and FLT, respectively) or 90°C (FVHT and GVHT, respectively). Experimental diets were fed to ten 1-month-old Wistar rats (body weight=176 (sem 15) g) for 21 d. Growth and nutritional, metabolic and inflammatory markers were measured and compared with an isonitrogenous casein diet (CD). The enrichment with faba bean increased the lysine, threonine and branched amino acids by 97, 23 and 10 %, respectively. Protein utilisation also increased by 75 % (P <0·01) in FLT in comparison to GLT diet, without any effect on the corrected faecal digestibility (P >0·05). Faba bean pasta diets' corrected protein digestibility and utilisation was only 3·5 and 9 %, respectively, lower than the CD. Growth rate, blood composition and muscle weights were not generally different with faba bean pasta diets compared with CD. Corrected protein digestibility was 3 % lower in GVHT than GLT, which may be associated with greater carboxymethyllysine. This study in growing rats clearly indicates improvement in growth performance of rats fed legume-enriched pasta diet compared with rats fed gluten–wheat pasta diet, regardless of pasta drying temperature. This means faba bean flour can be used to improve the protein quality and quantity of pasta. [ABSTRACT FROM AUTHOR]

An 8‐week feeding trial was conducted to investigate the dietary protein requirement of juvenile mandarin fish, Siniperca scherzeri, a demersal freshwater piscivore with high commercial value in East Asia. Five isolipidic (100 g/kg) and isoenergetic (20 MJ/kg) practical diets were formulated to contain graded levels of 450, 500, 550, 600, and 650 g/kg crude protein, using mackerel fishmeal as the sole source of protein. Each of the five test diets was fed to visual satiety to triplicate groups of fish (initial mean body weight ± SE; 20.1 ± 0.2 g) reared in a recirculating freshwater system over the experimental period. Fish growth performance in terms of weight gain tended to improve with increasing dietary protein level, and the highest values were observed in those fish fed the 600–650 g/kg diets. Feed intake significantly declined as the protein content of the diet increased. Feed efficiency and protein retention tended to increase with increasing dietary protein levels, from 450 to 600 g/kg, and then declined when dietary protein content further increased to 650 g/kg. A similar trend was also found for the protein efficiency ratio, although the observed changes did not reach statistical significance. Whole‐body composition and plasma biochemical parameters were not significantly affected by the dietary protein content. Based on these findings and a broken‐line model of growth, 614.4 g/kg seems to be the proper amount of protein in a practical diet for >20 g mandarin fish. [ABSTRACT FROM AUTHOR]

The research was conducted to know the effect and to determine the best utilization of the chiken feather silage meal as a substitute for fish meal protein source in the feed formula of Colossoma macropomum. This study used experimental method based on Completely Randomized Design (CRD) with 5 treatments and 3 replications. Five diets (33% isoprotein and 3.85 kcal/g diet isoenergi) were formulated with substitution of the chiken feather silage meal to fishmeal protein. These substituted 0, 25, 50, 75 and 100 % (A, B, C, D and E respectively) of the fishmeal protein. Parameters observed and analyzed were: survival rate, specific growth rate, feed conversion ratio, protein efficiency ratio, protein retention and protein digestibility. The results showed that the treatment had no effect on survival rate, specific growth rate, feed conversion ratio, protein efficiency ratio, and protein retention but the effect on protein digestibility. Based on these results, it can be concluded that fishmeal protein can be substituted with the chiken feather silage meal up to 100% in the feed formula of Colossoma macropomum.

Two trials were conducted to determine net protein requirements and the use of metabolizable protein (MP) for growing ram lambs when fed diets with different concentrate levels and roughage quality. In a comparative slaughter trial, eighty-four ½ Dorper × ½ Santa Inês ram lambs (18.0 ± 3.3 kg of BW) were individually penned and divided into 2 diet groups differing in roughage source: low-quality (sugarcane bagasse) roughage (LQR) or medium-quality (coastcross hay) roughage (MQR). In each group, 7 lambs were randomly selected and slaughtered after a 10 days adaptation period (baseline). Other 21 lambs from each diet group were fed ad libitum and slaughtered at 25, 35, or 45 kg of BW, and the remaining 28 lambs (14 from each diet group) were submitted to 1 of 2 levels of feed restriction (70 or 50% of the ad libitum intake). Body N content and retention were determined. In the second trial, 6 ram lambs (44.3 ± 5.6 kg of BW) were kept in metabolic cages and used in a 6 × 6 Latin square experiment designed to determine N digestibility and microbial N synthesis, and to compute MP supply by the 2 diets and 3 levels of intake. Nitrogen intake and microbial N synthesis were greater for the animals fed the MQR diet than for those fed the LQR diet ( P  < 0.05). Neither the endogenous and metabolic N losses, nor the net protein requirements for growth differed between diets ( P  > 0.05). However, the proportion of MP used for both maintenance and growth was lower for the animals fed the MQR diet ( P <  0.05), likely because of an excess of MP reaching duodenum of these animals. We concluded that a reduction of the concentrate level in diets for growing ram lambs, achieved by improving the quality of the diet roughage, allows a greater supply of MP and may contribute to reduce diet protein concentration. [ABSTRACT FROM AUTHOR]

Abstract: In this study, two different dietary protein levels were tested (500 and 600 g/kg) in meagre juveniles of approximately 2 g, to determine whether a higher body protein diet would favour muscle growth. Results showed that meagre survival and growth were not affected by different levels of dietary protein. However, a higher content of protein was observed in the body composition of meagre fed the P60 diet (656 g/kg versus 624 g/kg). When fish were 82 days after hatched (DAH), protein retention efficiency was significantly higher in fish that were fed the P50 diet (37.1% versus 32.5%). Muscle cellularity changed considerably from the beginning to the end of the trial. The contribution of fibre hyperplasia to muscle growth was reduced although still accounted for 30% in 96 DAH meagre. Several differences were found in the frequency of fibres with areas between 1,000 μm2 and 2,200 μm2 between younger and older meagre, but no effect was found associated with dietary protein. This study suggests that neither growth nor muscle cellularity of fast‐growing juvenile meagre is positively affected by an increased dietary protein levels. [ABSTRACT FROM AUTHOR]

A 12 week growth study was carried out to investigate the supplemental effects of dietary garlic powder (GP) on growth, feed utilization and whole body composition changes of fingerling sterlet sturgeon Acipenser ruthenus (averaging weight, 5.5 g). Following a 24-h fasting, 540 fish were randomly distributed to each of 18 tanks (30 fish/tank) under a semi-recirculation freshwater system. The GP of 0.5% (GP0.5), 1% (GP1), 1.5% (GP1.5), 2% (GP2) and 3% (GP3) was added to the control diet (GP0) containing 43% protein and 16% lipid. After the feeding trial, weight gain (WG) of fish fed GP1.5, GP2 and GP3 were significantly higher (p

Methionine-choline-deficient ( MCD) mammals are known to accumulate liver TAG probably due to phosphatidylcholine ( PC) deficiency and thus assembly of VLDL and transport of lipids from liver to peripheral organs. To assess whether supplementation of choline could spare methionine and secure a healthy liver metabolism, by reducing the endogenous PC synthesis without interfering with lipid transport and distribution, Atlantic salmon with initial BW of 700 g were fed adequate (1.9 g Met/16 gN) or surplus methionine (2.5 g Met/16 gN) diets of which were supplemented with choline or not for a period of 19 weeks. Fish fed the low-methionine diets had reduced growth ( p = .013) due to reduced protein gain ( p = .007), while lipid gain slightly improved in fish fed the choline-supplemented diets ( p = .047). Also, feed conversion improved when fed surplus methionine ( p < .001), while choline supplementation had no impact on feed conversion. No interaction between choline and methionine on growth performance or retention existed. Phospholipid status in liver and muscle was not affected by treatments, and no liver TAG accumulation occurred at the methionine levels used. Gene expression of ApoB100 necessary for assembling VLDL or pemt necessary for endogenous PC synthesis was unaffected by treatments. Capacity of methylation ( MAT, BHMT) within the liver was not affected by treatment nor was the gene expression of enzymes in liver transsulfuration ( CBS or CDO). Methionine status within liver was unaffected by treatments, while free methionine reduced in those fish fed the low-methionine diets in muscle and plasma. Cystathionine and taurine were elevated when fed surplus methionine. Choline supplementation had no impact on sulphur amino acid metabolites in either tissue. Neither did choline supplementation improve TAG mobilization from liver to muscle. To conclude, choline does not improve endogenous phospholipid synthesis or transport of TAG from liver to muscle depot when added to diets containing 1.9 g Met/16 gN, while surplus methionine improved growth and protein retention, indicating that 1.9 g Met/16 gN is enough to support a healthy liver metabolism, but too low to support muscle protein deposition in adult salmon fed high plant protein diets for longer periods of time. [ABSTRACT FROM AUTHOR]

The purpose of this work was to evaluate the effect of the temperature (50 and 60 °C) of a NaOH cleaning solution during the diafiltration of a binary mixture of bovine serum albumin and β-lactoglobulin, through a 300 kDa tubular ceramic membrane along repeated operational cycles. To this aim, final permeate volume, membrane and fouling resistances and individual protein concentration were analyzed. At the end of each individual study, the membranes were characterized by liquid-liquid displacement porosimetry. As a result, 50 °C was found to be the most appropriated temperature due to its higher capability to restore the initial membrane resistance and the higher efficiency achieved in terms of protein separation. Both conditions fulfilled without altering the structural properties of the membrane as given by porosimetric analysis. In contrast, a great fouling resistance involving null protein transmission occurred when cleaning was performed at 60 °C. [ABSTRACT FROM AUTHOR]

Fed-batch and perfusion cell culture processes used to produce therapeutic proteins can use microfilters for product harvest. In this study, new explicit mathematical models of sieving loss due to internal membrane fouling, external membrane fouling, or a combination of the two were generated. The models accounted for membrane and cake structures and hindered solute transport. Internal membrane fouling was assumed to occur due to the accumulation of foulant on either membrane pore walls (pore-retention model) or membrane fibers (fiber-retention model). External cake fouling was assumed to occur either by the growth of a single incompressible cake layer (cake-growth) or by the accumulation of a number of independent cake layers (cake-series). The pore-retention model was combined with either the cake-series or cake-growth models to obtain models that describe internal and external fouling occurring either simultaneously or sequentially. The models were tested using well-documented sieving decline data available in the literature. The sequential pore-retention followed by cake-growth model provided a good fit of sieving decline data during beer microfiltration. The cake-series and cake-growth models provided good fits of sieving decline data during the microfiltration of a perfusion cell culture. The new models provide insights into the mechanisms of fouling that result in the loss of product sieving. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1323-1333, 2017 [ABSTRACT FROM AUTHOR]

Two experiments were conducted to study the possibility of utilizing enzyme incubated rape seed meal (RSM) in broiler diets (1 to 42 day of age). The RSM was anaerobically incubated with non-starch polysaccharide hydrolyzing enzymes (cellulase 1,500 IU, xylanase 250 IU and pectinase 125 IU per kilogram) for 300 minutes (processed RSM1, experiments 1 and 2) and 600 min (processed RSM2, experiment 2). Processed and raw RSM contained similar concentration of glucosinolates (275 and 288 mM/g, respectively). During the experiment 1, maize-soybean meal control diet (CD), two diets with raw (RRSM) and processed RSM (PRSM1) at 100 g/kg each were prepared. In the experiment 2, RRSM, PRSM1 and PRSM2 were included each at 3 levels (50, 100 and 150 g/kg). Each diet was offered to 9 replicates having 5 birds in each. Body weight gain (BWG), feed intake (FI), feed efficiency (FE), ready to cook (RTC) yield and breast weight were depressed by incorporating RRSM (experiments 1, 2). As a result of this study, PRSM1 significantly reduced FI, maintained BWG and improved FE compared to the control group. BWG was not affected by including PRSM1 and PRSM2 up to 100 and 50 g/kg, respectively but depressed at higher inclusion levels compared to the CD. The BWG in processed RSM fed groups were higher than the respective level of raw RSM fed groups. Retention of energy and protein were improved by incorporating processed RSM compared to those fed RRSM. Based on the data, it is concluded that enzyme (cellulase, xylanase and pectinase) incubated RSM for 300 minutes improved the nutritional value, which can be incorporated up to 100 g/kg in broiler diet without affecting performance and slaughter variables, which can be attributed to the improved retention of energy and protein in RSM based diets. [ABSTRACT FROM AUTHOR]

Proper nutrient management is essential for the environmental sustainability of aquaculture. While increasing daily rations generally may lead to improved growth rates, this does not necessarily mean that nutrients are utilized more efficiently. To investigate how ration size affects partitioning of dietary nutrient intake, the effects of meal size on growth and metabolism were examined in triplicate groups of adult Nile tilapia ( Oreochromis niloticus ) receiving daily rations corresponding to 1, 2, 3, or 4% of their biomass. While biomass gain and specific growth rates were positively correlated with ration size, feed conversion and protein retention were most efficient at ration sizes of 3%. Although the magnitude of the SDA response following feeding also increased with ration size, this was not proportionate to meal size. Therefore the metabolic cost of meal processing (SDA coefficient) was found to be lowest in the 3% ration group. The lowest rates of nitrogen excretion as well as the lowest SDA coefficients were also observed for fish receiving meal sizes corresponding to 3% of their body mass. In contrast, fish fed ration sizes of 1% displayed a reduction in apparent digestibility of protein, nitrogen free extract and dry matter, in addition to excreting a disproportionate amount of ingested nitrogen as ammonia and urea. [ABSTRACT FROM AUTHOR]

The objective of the research was to know the best method of processed-shrimp wastes on protein consumption and retention. Experiment was designed using completely randomized design with five treatments of ration and four replications. Treatments were basal ration with added by 5% shrimp waste. Treatments were D0 (basal diet + non treated shrimp waste), D1 (basal diet + shrimp waste hydrolyzed by 3% NaOH), D2 (basal diet + shrimp waste hydrolyzed by 6% NaOH), D3 (basal diet + shrimp waste hydrolyzed by 5% H2O2), and D4 (basal diet + shrimp waste fermented by Aspergillus niger). The total number of treated chicken was 20 broiler of MB 202 strain. To compare the effect of treatments, data was analyzed using least square difference. Results showed that the treated shrimp waste had potential to use as protein source in broiler diet and the best consumption and retention protein was found in hydrolysis shrimp waste by 3% NaOH and 5% H2O. (Animal Production 12(1): 1-5 (2010)Key Words: shrimp waste, protein consumption, protein retention, broiler, Aspergillus niger

Nutritional requirements of the Iberian pig, a slow-growing, obese porcine breed, are not well defined and seem to differ from those of conventional or high-performing pigs. The effects of the dietary protein content and the feeding level on the utilisation of metabolisable energy (ME) and the rates of gain, protein, and fat deposition were studied with 81 Iberian castrates growing from 50 to 100 kg body weight (BW) by using the comparative slaughter technique. The animals were fed 4 diets providing 145, 120, 95, and 70 g ideal crude protein (CP) per kg dry matter (DM), and containing 13.94, 14.29, 14.56, and 14.83 MJ ME per kg DM, respectively. Three levels of feeding were evaluated: 0.60, 0.80, and 0.95 × ad libitum intake. Growth rate increased (linear and quadratic, P

The study was conducted using channel catfish and tilapia to evaluate the production performance of these fish to increasing levels of lysine from crystalline and intact lysine supplemented in practical diets. A practical lysine deficient basal diet was developed using corn protein concentrate (Empyreal® 75) as a primary protein source. To this diet either graded levels of crystalline lysine or similar levels from a high lysine corn protein concentrate (Lysto™) were added. In the channel catfish trial, the first five diets were designed to contain increasing levels of crystalline lysine (1.21%, 1.34%, 1.45%, 1.56%, and 1.72%) with an additional four diets using intact protein from a high lysine corn protein concentrate (1.40%, 1.57%, 1.77%, and 1.91% lysine). In the tilapia trial, lysine from two sources was added to 11 diets to produce analyzed lysine levels of 0.92%, 1.11%, 1.23%, 1.34%, 1.54% 1.65% in the first six diets using crystalline lysine and 1.13%, 1.38%, 1.61%, 1.81%, 2.02% in the last five diets using intact lysine. Results indicated that channel catfish and tilapia have positive performance with increasing lysine supplementation up to the requirement. Fish fed with the higher levels of lysine had the highest weight gain and lowest feed conversion ratio. The regression analysis on the increased level of inclusion of crystalline lysine and intact lysine showed no significant difference in slope. Based on the growth, feed conversion ratio and apparent net protein retention data obtained from this study, it can be concluded that the effectiveness of using intact lysine via high lysine corn protein concentrate as a lysine supplement is not significantly different from crystalline lysine. Thus, the high lysine corn protein concentrate is a feasible ingredient for aquaculture feeds, which can be used to balance the amino acid composition of the diet without addition of crystalline lysine. Statement of relevance Present study shows that high lysine corn protein concentrate is a feasible ingredient for aquaculture feeds, which can be used to balance the amino acid composition of the diet without addition of crystalline lysine. [ABSTRACT FROM AUTHOR]

Four diets were formulated to evaluate the partial to total substitution of fishmeal with poultry by-product meal ( PBM) (0, 33, 67 and 100 PBM) in diets for totoaba juveniles ( Totoaba macdonaldi). Amino acid profiles from diets and fatty acid content in diets and muscle tissue were used to assess the fish performance using PBM as fishmeal replacement. Stable isotopes of nitrogen (δ15N) were measured in muscle and liver tissue to quantify the retention of each protein source. At the end of the experimental period, the fish fed the 67 PBM diet had a significantly higher growth gain increase compared to the other treatments (almost 2000% over an 86 days period; TGC of 1.06). The total replacement of fishmeal with PBM led to low growth gain increase (ca. 220% over 72 days; TGC of 0.52) and increased mortality. Both fish performance and tissues' fatty acid composition suggest that the 100 PBM diet was deficient in essential fatty acids. An isotope-mixing model applied to isotope ratios of muscle and liver tissues of fish fed the 67 PBM tissues indicated that PBM was retained into muscle and liver tissue in a higher proportion than its level of inclusion in the diet. We conclude that PBM is a good source of nutrients for totoaba juveniles when used in up to 67% fishmeal replacement level in diets containing 52% protein leading to adequate growth rate and survival. [ABSTRACT FROM AUTHOR]

This study compares growth, intake and retention efficiencies of nutrients and energy between common sole ( Solea solea L.) fed ragworm ( Nereis virens, Sars), blue mussel ( Mytilus edulis L.) and an artificial (commercial) feed. Food types were fed to common sole (mean initial body weight: 44.9 ± 2.3 g) in excess three times a day over a 54-day-period. The growth rate in common sole fed the natural prey (8.5 g kg−0.8 d−1) was significantly higher compared to the growth rate in fish fed the artificial feed (5.1 g kg−0.8 d−1). Nutrient and energy intake was significantly lower in common sole fed the artificial feed than in fish fed natural prey. The only exception was fat intake which was higher in common sole fed the artificial feed in contrast to fish fed the natural prey. Nutrient and energy retention efficiencies were significantly lower in common sole fed the artificial feed than in fish fed the natural prey. In conclusion, the low growth in common sole fed the artificial feed was related to lower nutrient and energy intake as well as lower nutrient and energy retention efficiencies. It is suggested that reduced intake of the artificial feed might be related to the high dietary fat content of the artificial feed. [ABSTRACT FROM AUTHOR]