Poultry By-product Meal Research Articles

Dietary supplementation of black soldier fly (Hermetica illucens) meal modulates gut microbiota, innate immune response and health status of marron (Cherax cainii, Austin 2002) fed poultry-by-product and fishmeal based diets.

The present study aimed to evaluate the dietary supplementary effects of black soldier fly (Hermetia illucens) (BSF) meal on the bacterial communities in the distal gut, immune response and growth of freshwater crayfish, marron (Cherax cainii) fed poultry-by-product meal (PBM) as an alternative protein source to fish meal (FM). A total of 64 marron were randomly distributed into 16 different tanks with a density of four marron per tank. After acclimation, a 60-days feeding trial was conducted on marron fed isonitrogenouts and isocalorific diets containing protein source from FM, PBM, and a combination of FM + BSF and PBM + BSF. At the end of the trial, weight gain and growth of marron were found independent of any dietary treatment, however, the two diets supplemented with BSF significantly (P < 0.05) enhanced haemolymph osmolality, lysozyme activity, total haemocyte counts, and protein and energy contents in the tail muscle. In addition, the analysis of microbiota and its predicted metabolic pathways via 16s rRNA revealed a significantly (P < 0.05) higher bacterial activity and gene function correlated to biosynthesis of protein, energy and secondary metabolites in PBM + BSF than other dietary groups. Diets FM + BSF and PBM + BSF were seen to be associated with an up-regulation of cytokine genes in the intestinal tissue of marron. Overall, PBM + BSF diet proved to be a superior diet in terms of improved health status, gut microbiota and up-regulated expression of cytokine genes for marron culture.

Apparent digestibility coefficients of selected protein ingredients for pirarucu Arapaima gigas (Teleostei: Osteoglo ssidae)

Apparent digestibility coefficients (ADCs) of nine protein ingredients were determined for pirarucu Arapaima gigas , a Neotropical fish species with great aquaculture potential in the Amazon. ADCs of crude protein, energy and dry matter were determined by feces sedimentation in cylindrical-conical tanks. Experimental diets were composed of 795 g kg -1 of the reference diet, 5 g kg -1 of chromic oxide and 200 g kg -1 of the following test ingredients: fish by-product meal, salmon by-product meal, poultry by-product meal, hydrolyzed feather meal, meat and bone meal, blood meal, soybean meal, corn gluten meal and corn gluten feed. Blood meal, meat and bone meal and corn gluten feed resulted in low ADCs for pirarucu, whereas corn gluten meal, poultry by-product meal and soybean meal were better digested, indicating that these ingredients may be potential protein sources in feed formulations for pirarucu. The other animal protein ingredients presented intermediate ADCs values and, together with blood meal and meat and bone meal, they demonstrate that the nutritional quality of the animal by-products tested could be improved, especially by enhancing the processing methods of this group of ingredients.

Poultry by-product meal as dietary protein source for dourado, Salminus brasiliensis: an economic appraisal

ABSTRACT: The dourado, Salminus brasiliensis, a large, carnivorous, Neotropical, Characin, is highly regarded for fish farming and sport fishing alike. However, studies on the farming and husbandry of dourado are still scarce. This study evaluated the performance of dourado fed diets formulated so as to contain increasing levels of poultry by-product meal as a replacement for fish meal and aimed to identify the maximum level of replacement to maximize profit. The trial was set up in a closed recirculation system with controlled water quality (temperature 27 °C, dissolved oxygen 6.5 mg L−1, pH 7.4, and ammonia 0.25 mg L−1). Juvenile fish were stocked in tanks in a completely randomized design, acclimatized to system conditions and experimental diets, and then fed twice a day for 66 days with extruded, nutritionally complete diets (40 % digestible protein and 4020 kcal kg−1 digestible energy), formulated to contain 0, 20, 40, 60, 80 or 100 % poultry meal as a surrogate protein source for fish meal. Performance parameters – average weight gain, specific growth rate, feed consumption, feed conversion rate, protein efficiency rate, productive value of protein, energy retention rate, survival rate – did not differ (p > 0.05). To minimize the effects of influential data, the robust regression method was used and profit maximization analysis revealed that replacing 33.3 % of dietary fishmeal by poultry by-product meal maximizes profit in the farming of dourado.

Growth performance, digestibility, and blood biochemical parameters of Nile tilapia (Oreochromis niloticus) reared in floating cages and fed poultry by-product meal

ABSTRACTA 120-day feeding trial was conducted in floating cages to evaluate growth performance and digestibility of Nile tilapia (Oreochromis niloticus) juveniles fed diets containing different levels of poultry by-product meal (PBM) as a replacement for fishmeal. Nile Tilapia with an average body weight of 56.6 ± 0.28 g were used in this experiment. Five diets were formulated to contain graded levels of PBM at 0%, 5%, 10%, 20%, and 30% poultry by-product meal (PBM) and are referred as PBM0, PBM5, PBM10, PBM20, and PBM30, respectively. Groups of 25 Nile tilapia were fed close to the apparent satiation, three times a day. The results showed that growth performance, survival and whole-body composition for fish fed the experimental diets were not significantly different (P > .05) than fish fed the control diet. Apparent digestibility of dry matter, protein, lipid and amino acids of fish fed the PBM20 and PBM30 were lower compared to the other treatments (P < .05). The PBM dietary levels significantly lowered total protein, high-density-lipoprotein (HDL) and cholesterol concentration. The results of this study indicated that good quality PBM can be used up to 30% in commercial diets for Nile tilapia without any adverse effect.

Bioprocessed poultry by-product meals on growth, gut health and fatty acid synthesis of juvenile barramundi, Lates calcarifer (Bloch).

Poultry by-product meal (PBM) has been utilised as a substitute of fishmeal (FM) in many aquaculture species. However, little information is known regarding the use of bioprocessed PBM (BPBM) in aquaculture production. This study was undertaken to investigate whether replacing FM with BPBM improved growth performance, gut morphology and fatty acid synthesis of juvenile barramundi, Lates calcarifer. The PBM was bioprocessed by baker yeast, Saccharomyces cerevisae and Lactobacillus casei. The BPBM was used to replace FM at 75% and 100% (75BPBM and 100BPBM) contrasting against unprocessed PBM (75PBM and 100PBM) at the same levels and FM based diets as the control. Juvenile barramundi with a mean initial weight of 3.78±0.16 g were stocked at a density of 20 fish per tank. After the 42 days of study, the final weight, specific growth rate and feed conversion ratios of fish fed 75PBM and 75BPBM were not significantly different from the control. However, 100% supplementation diets of 100PBM and 100BPBM resulted in reduced performance in all growth and feed variables except total feed intake and survival. The hind gut microvillus density was significantly higher (P<0.05) in fish fed 75BPBM, whereas the microvillus diameter remained unaffected with the other experimental diets when compared to the control. A reduction in eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids of fish muscles led to a lower Σn−3/Σn−6 ratio in all dietary groups when compared to the control. The percentage of Σn-3 PUFAs decreased in 100% FM replacement diets of 100PBM and 100BPBM, while Σn−6 PUFAs increased when both bioprocessed and unprocessed PBM protein was increased in the diets. Fish fed bioprocessed diets had higher fatty acid hypocholesterolemic/hypercholesterolemic ratios (HH), indicating improved suitability for human consumption.

Microbiological status based on 454-pyrosequencing and volatilome analysis of gilthead seabream (Sparus aurata) fed on diets with hydrolyzed feather meal and poultry by-product meal as fishmeal replacers

The effect of two experimental diets with different animal protein sources on sensory, microbiological and chemical attributes of Sparus aurata flesh stored at chilling temperatures were explored through sensory evaluation, tag-pyrosequencing of the 16S rRNA gene (V3–V4 region) and SPME–GC/MS. respectively. The 50% replacement of fishmeal by either hydrolyzed feather meal (HFM) or poultry by-product meal (PBM), did not affect the initial microbial composition of seabream. Differences were observed on spoiled fish indicating that the diet with non-ruminant processed animal protein (PAPs) in combination with the applied storage conditions affect the selection of spoilage microbiota. Minor differences were also detected in volatile compounds profile of PAP-fed seabream showing no strong effect on flesh quality of fish. This research constitutes the baseline for further investigation on the use of non-ruminant PAPs in fish diets in order for aquaculture to produce a high quality of farmed fish for the consumer.

Beneficial effects of tuna hydrolysate in poultry by-product meal diets on growth, immune response, intestinal health and disease resistance to Vibrio harveyi in juvenile barramundi, Lates calcarifer

This study was conducted to investigate the effects that tuna hydrolysate (TH) supplementation in poultry by-product meal (PBM) diets would have on growth, immunity and resistance to Vibrio harveyi infection in juvenile barramundi, Lates calcarifer. Five isonitrogenous and isocaloric diets containing fishmeal (FM) without TH supplementation (control) and four diets with 10% TH supplementation viz. a FM protein diet (FMBD + TH), a 75% PBM protein diet (LPBM + TH) and two 90% PBM protein diets, either bioprocessed (BPBM + TH) or unprocessed (HPBM + TH), were formulated for juvenile barramundi, Lates calcarifer. The diets were fed to triplicate groups of juvenile barramundi (average pool weight 12.63 ± 0.11 g) for 10 weeks. Significantly (P < 0.05) higher final body weights and specific growth rates were noted in fish fed with FMBD + TH and BPBM + TH diets when compared to the control. Transmission electron microscopy observation of fish distal intestines revealed a significant enhancement of microvilli length in fish fed FMBD + TH and BPBM + TH whereas scanning electron microscopy analysis found no significant difference in microvilli density. A bacterial challenge with Vibrio harveyi was conducted for 14 days after the growth trial to test the immune response and survival of barramundi. In the pre-challenge condition, a significant reduction in blood glucose was found in BPBM + TH compared to the control, and fish in the post-challenge at 24 h had higher glucose levels compared to fish in the pre- and post-challenge conditions at 72 h. The serum lysozyme activity was significantly higher in FMBD + TH and BPBM + TH compared to the control and fish at 72 h post-challenge exhibited higher lysozyme activity in each treatment compared to all dietary groups in the post-challenge condition at 24 h and to HPBM + TH and BPBM + TH in the pre-challenge condition. Fish fed FMBD + TH, LPBM + TH and BPBM + TH diets had significantly higher survival to the bacterial challenge than fish in the control and HPBM + TH. These results showed that PBM supplemented with TH could successfully replace FM without compromising growth, however, bioprocessed PBM supplemented with TH (BPBM + TH) may significantly improve growth performance, immune response, intestinal health and disease resistance in juvenile barramundi.

Effects of different dietary protein sources on the immunological and physiological responses of marron, Cherax cainii (Austin and Ryan, 2002) and its susceptibility to high temperature exposure

A two phased feeding trial was conducted to evaluate the effects of alternative protein sources on the immunophysiological responses of marron. During the phase I, marron were fed with five alternative protein supplemented diets for 90 days, while in phase II, the same marron were exposed to elevated temperature (30 °C) and their immunophysiological responses were investigated post exposure. Five isoproteic (crude protein 30%) and isoenergetic diets were prepared by containing fishmeal, poultry by-product meal, feather meal, lupin meal, and meat and bone meal as the main protein source. A hundred and fifty juvenile marron (Cherax cainii) of the average weight 9.09 ± 0.21 g were randomly distributed into 15 tanks (three replicates per feeding treatments). In the Phase I, general immune response parameters, such as, total haemocyte count (THC), proportion of hyaline cells, neutral red retention time (NRRT), phagocytic rate (PR), heamolymph bacteraemia, and condition indices of marron were investigated. The highest (P < 0.05) THC among dietary protein sources was obtained in marron fed with PbM at the end of experiment. Marron fed with FeM protein sources resulted in the highest survival rate followed by PbM fed group. Longer microvilli length (3.83 ± 0.18 μm) was demonstrated in marron fed with PbM diet. Diets containing FM and PbM protein sources revealed significantly (P < 0.05) lower number of microvilli/group than diets containing FeM and LM. The results demonstrated that different dietary protein sources in the marron diets did not detect significant (P > 0.05) change of the condition indices throughout the experiment period, however highest Hiw and Hid was recorded in marron fed with PBM at day 45. The PR of marron fed dietary protein from PbM did not change significantly after temperature exposure. Increased NRRT, PR and haemolymph bacteraemia was observed with dietary feeding of FM at the end of the trial. However, results revealed that PbM could be an alternative protein source for culture of marron as reflected in terms of increased THC, longer microvillus length and improved susceptibility to high temperature exposure. Overall, result could serve as useful baseline data in developing cost effective potential diets for marron aquaculture.

USING OF ANIMAL BY PRODUCTS AS AN ALTERNATIVE PROTE

Four diets were formulated to include different sources of animal by-products as a protein source in Nile tilapia (5.79 ± 0.05 g) diets. The first group fed diet containing fish meal (T1), while the 2nd, 3rd and 4th groups fed a mixture of poultry by-product meal (PBM), animal by-product meal (ABM) and kitchen waste meal (KWM) at 50:25:25 (T2); 25:50:25 (T3) and 25:25:50 (T4) ratio, respectively. All diets were formulated to be isonitrogenous and isolipidic. After 120 days, apparent digestibility and growth parameters were measured. The obtained results revealed that, the chemical composition of fish meal had the highest value of protein followed by PBM and KWM. Fish meal had higher essential amino acids content, except for the threonine and arginine amino acids, followed by PBM and ABM. The highest apparent digestibility of crude protein and ether extract were recorded in T1 and T2 followed by T4 and T3 groups. T1 and T2 groups exhibited significantly (P&lt;0.05) the highest growth performance over fish fed T3 and T4 diets. It could be suggested that using of waste protein sources especially containing high PBM as a replacement for fish meal to reduce the feed cost per Kg fish Production.Key words: animal by products; aigestibility; aish meal; arowth; Nile tilapia

Optimization of rendering process of poultry by-products with batch cooker model monitored by electronic nose

The best available controlled technology for transforming the disposal of animal by-products and mortalities is rendering. Two aspects of rendering process are mentioned in this research; product quality and emissions. A model of batch cooker with temperature, pressure and agitator speed controllers was designed and developed in order to optimize the process and to investigate the effect of changes in rendering conditions on quality of poultry by-product meal and also on pollutant emissions. An electronic nose system was designed and built based on metal oxide semiconductor sensors to monitor the gases emitted from batch cooker model. Also, GC-MS was used to identify the emitted components. In order to optimize the rendering process, response surface methodology was performed on temperature, cooking time and agitator speed variables. Results showed that the temperature of 140 °C (internal pressure equivalent to about 3.2 bar), the cooking time of 45 min and the agitator speed of 20 rpm optimized the process of batch cooking to maximize the percentage of protein and minimize the percentage of fat, moisture content, energy consumption and emission of pollutants. By GC-MS analysis, about 100 compounds include hydrocarbons, volatile fatty acids, sulfur-containing compounds, alcohols, ketones, aldehydes, and furans were observed in the emission of a batch cooker model. The major groups were organic acids and amides. Principle component analysis showed the most suitable sensors for detecting unpleasant odors from rendering plants.

Autolyzed Yeast (Saccharomyces cerevisiae) Supplementation Improves Performance While Modulating the Intestinal Immune-System and Microbiology of Broiler Chickens

The objective of this study was to evaluate the effects of dietary autolyzed yeast (AY; Saccharomyces cerevisiae) supplementation on growth performance, immune system, and intestinal bacterial count in broiler chickens. A total of 1,260 one-day-old male Ross AP95 chicks were placed in a completely randomized design (4 treatments, 7 replicates each, and 45 birds/replicate). The treatments were: basal diet – negative control (NC); basal diet supplemented with 55 ppm of zinc bacitracin – positive control (PC); NC + 0.2% of AY; NC + 0.4% of AY. The diets were formulated based on corn-soybean meal with 5% inclusion of wheat bran and 5% of poultry by-product meal. At 7 days of age, all birds were eye drop-vaccinated with live vaccine against coccidiosis. At 8 and 21 d of age, one chicken per pen was then euthanized by cervical dislocation to collect ileal and cecal contents for enumeration of Enterococcus sp., Escherichia coli and Lactobacillus sp. Yet, ileal samples were collected to analyze the gene expression of Claudin-1, IL-1β, IL-4, TLR-4 and MUC-2 through real time PCR. On d 21, it was observed that the inclusion of 0.2% of AY improved FCR (P < 0.05) when compared to the NC treatment. In the overall experimental period, the inclusion of zinc bacitracin and 0.4% of AY improved FCR (P < 0.05) compared to the NC group. On d 8, supplementation of 0.2 % of AY increased Enterococcus and both concentrations of AY reduced Lactobacillus in the ileal digesta compared to birds supplemented with zinc bacitracin. On d 21, 0.2% of AY reduced E. coli in the cecal digesta. On d 8, AY supplementation downregulated the expression of TLR-4 vs. the PC group (P = 0.04). On d 21, supplementation of AY upregulated the expression of IL-1β (P < 0.05) vs. the NC group. Supplementation of AY improved the growth performance of broiler chickens vaccinated against coccidiosis, partially explained by the modulation of the intestinal microbiota and immune-system.

THE EFFECTS OF DIFFERENT DIETARY PROTEIN SOURCES ON THE GROWTH PERFORMANCES AND BODY COMPOSITION OF THE ROCK PORGY, OPLEGNATHUS FASCIATUS

This study investigated the effects of different dietary protein sources on the growth performance and muscle composition of the rock porgy, Oplegnathus fasciatus. Four isonitrogenous (48% crude protein) and isolipidic (10% crude lipid) diets were formulated with Peruvian fishmeal (PFM), Taiwanese fishmeal (TFM), poultry by-product meal (PBM) and meat and bone meal (MBM), respectively. The rock porgy (mean initial weight 10.58 g) were reared in 12 tanks and fed with one of the four treatment diets in triplicate for six weeks. The rock porgy fed with diet TFM had significantly higher weight gain than those fed with the other treatment diets. However, the rock porgy fed with diet MBM had significantly lower weight gain than those fed with the other treatment diets. Survival for all treatment groups ranged from 90 to 100%. Feed conversion ratio (FCR) of the rock porgy fed with diet TFM was lower than that of the fish fed with the other diets. The hepatosomatic index (HSI) of the rock porgy fed with diet PFM was lower than that of the fish fed with the other diets. The specific growth rate (SGR) of the rock porgy fed with diets TFM, PFM and PBM was significantly higher than that of fish fed with diet BMB. Therefore, it is suggested that TFM is the optimum protein source for the rock porgy.

DESIGN AND MANUFACTURE OF A COOKING UNIT FOR PRODUCING POULTRY BY-PRODUCTS MEAL AS NON-TRADITIONAL FEED

Test Experiments were carried out to design, manufacture and evaluate the performance of a cooking unit used for rendering poultry abattoir residues (intestines and legs residues) and investigate the effect of using these by-products in feeding Nile tilapia fish. The performance of the manufactured cooker was studied under the following parameters: Three different poultry abattoir treatments were 100% intestines, 50% legs + 50% intestines and 100% legs under four different agitating speeds 20, 30, 40 and 50 rpm and was evaluated taking into consideration the following indicators: productivity, cooking efficiency, total losses, specific energy and criterion costs through the first experiment. With regard to the second experiment was aimed to investigate the effect of different levels of poultry by-product meal on the feed utilization and whole-body composition of Nile tilapia fish. Growth performance was studied taking into consideration both of feed efficiency ratio and protein efficiency ratio. The results reveal that the highest values of machine productivity and cooking efficiency were (52.30 kg.h-1 and 97.90%), while the lowest values of the total losses and criterion cost were (2.10% and 1500 LE.Mg-1), respectively under agitating speed of 40 rpm with adjusting vapor pressure on 2 bar using 50% intestines + 50% legs residue. Furthermore, the obtained results show that there is no difference in growth performance and feed utilization between Nile tilapia fish when feeding on diets have 25 and 50% of poultry by-product meal i.e. 75 and 50% of fish meal.

The effect of poultry protein concentrate and phosphorus supplementation on growth, digestibility and nutrient retention efficiency in barramundi Lates calcarifer

Two experiments were conducted on juvenile barramundi testing the replacement of regular poultry by-product meal (PBM) with a premium grade poultry protein concentrate (PPC). In the first experiment, a series of five iso-nitrogenous and iso-calorific dietary treatments composed of incrementally increasing levels of PPC from 0% to 20%, substituting PBM were formulated (PPC0, PPC5, PPC10, PPC15, PPC20). The diets were restrictively pair-fed to 63g barramundi for 56 days. In the second experiment, a series of four iso-nitrogenous, iso-calorific and iso-phosphoric dietary treatments composed of incrementally increasing levels of PPC from 0% to 20% substituting PBM were formulated (PPC0+P, PPC6.7+P, PPC13.3+P, PPC20+P). An additional dietary treatment was formulated without any phosphorous supplementation (PPC20-P). The diets were restrictively pair-fed to 69g barramundi and the PPC20+P and PPC20-P were also tested when fed to satiation for 42 days. Experiment 1 demonstrated a clear linear trend towards poorer growth performance and feed utilisation when increasing the level of PPC in the diet. Significant differences were noted for final weight, weight gain, SGR and FCR (P<0.05) in the fish fed diets PPC15 and PPC20 compared to the PPC0. Protein retention efficiency and the apparent biological value of protein and energy was lower (P<0.05) in the PPC20 compared to the PPC0 fed fish. The apparent digestibility of crude protein, gross energy, phosphorous and several amino acids all increased with increasing level of PPC in the diet. In experiment 2, using iso-phosphoric diets, the reverse trend was demonstrated whereby increasing PPC improved the performance of barramundi. Significant differences were noted for the final weight, weight gain, SGR and FCR (P<0.05). When comparing the PPC20+P and the PPC20-P fed fish, there was a clear negative impact of not supplementing phosphorus, which was further compounded in fish fed to satiation (interaction, P<0.05). There were no significant differences in nutrient retention with the exception of calcium which increased with increasing PPC, and energy retention being higher in fish fed PCC20+P than PCC20-P treatments. The results of these two experiments demonstrate that the effective replacement of regular PBM with high quality PPC is achievable and when the diets are supplemented with phosphorus to an inclusion >1.5%, promotes faster growth, for fish fed restrictedly and to satiation. The results indicate a pressing need to redefine the phosphorus requirement of barramundi juveniles, notably to ensure the scope for growth is not affected when testing the nutritional value of novel protein sources.

Effect of fishmeal replacement by poultry by-product meal on growth performance, proximate composition, digestive enzyme activity, haematological parameters and gene expression of gilthead seabream (Sparus aurata )

Effect of fishmeal replacement by poultry by-product meal on growth performance, proximate composition, digestive enzyme activity, haematological parameters and gene expression of gilthead seabream (<i>Sparus aurata</i> )

A comparison of in-vivo and in-vitro methods for assessing the digestibility of poultry by-product meals using barramundi (lates calcarifer); impacts of cooking temperature and raw material freshness

Rendered terrestrial animal by-product meals (ABPM) are commonly used in aquafeeds for fish and shrimp. However, the nutrient composition and digestibility of these products is often variable due to differing processing conditions. As such, the aquafeed industry could benefit from technologies that rapidly assess the nutritional quality of ABPM prior to purchase and their incorporation into aquafeeds. To be useful, new technologies would need to accurately reflect the results of traditional assays such as in-vivo apparent digestibility. This study presents a comparison of three methods for assessing the protein digestibility of poultry by-product meals (PBMs) that were subjected to different cooking temperatures (between 110 °C to 145 °C) and pre-rendering storage times (between 0 and 8 h). The first method was a traditional in-vivo assessment of digestibility based on indirect techniques and the collection of faecal material from Barramundi (Lates calcarifer). The second was the in-vitro pepsin nitrogen digestibility assay applied at pepsin concentrations of 0.2% and 0.0002%, respectively. The third method employed a two-step, membrane bioreactor (also known as a gastro intestinal model or GIM), based on digestive enzymes collected from the gut of Barramundi. In-vivo protein digestibility of PBMs ranged from 57% to 83%, being lowest in PBM that had been purposely overheated (145 °C) and highest in PBM subjected to the lowest cooking temperature (110 °C). In-vivo amino acid digestibility followed similar trends. Estimates of protein digestibility and protein hydrolysis based on the pepsin assays and the GIM were highly correlated with in-vivo protein ADCs. Estimated protein digestibility based on the pepsin assays was similar in magnitude to those determined in-vivo. Estimates of protein digestibility based on the GIM (protein hydrolysis) were highly correlated with the other methods, but the values estimated using GIM were much lower. Despite this discrepancy the GIM data could be modelled with a high degree of certainty using quadratic functions, and these functions could be used to reliably estimate digestibility of protein from PBMs, at least for the data generated in this study. All methods were sensitive enough to distinguish between PBMs that had been carefully treated prior to rendering or PBM that had been purposely overheated. The use of GIM technology requires further development, however it offers a great deal of promise and the opportunity to rapidly assess the protein quality of many different raw materials.

DHA (22:6n-3) supplementation is valuable in Totoaba macdonaldi fish oil-free feeds containing poultry by-product meal and beef tallow

It was evaluated the effect of DHA (extract from Aurantiochytrium sp.) inclusion in diets formulated with poultry by-product meal (PBM) using beef tallow (TALLOW) to fulfill the lipid demand in substitution of fish oil (FO) in juvenile totoaba (9.5 ± 0.1 g). With this purpose four diets were formulated to contain PBM with FO (PBM + FO positive control) or TALLOW (PBM + TALLOW negative control) and two diets containing different levels of DHA; one supplemented with 50% (PBM + TALLOW+50%DHA) and 100% DHA (PBM + TALLOW+100%DHA), based on DHA requirements for marine carnivore fish. After nine weeks, no signs of fatty acid (FA) deficiency were noticed; survival was above 92% across dietary treatments, and production performance was also similar, with exception of feed conversion ratio and viscerosomatic index. Tissues proximate composition was affected by dietary treatments. Tallow-based diets increased hepatic lipid content. However, 100% DHA supplementation adjusted this effect. Overall blood parameters were not influenced by tallow inclusion, except for triglycerides. Fish fed the PBM + TALLOW diet exhibited significant higher levels of triglycerides compared to those fed the PBM + FO diets. However, the DHA supplementation in both levels amended this effect. The FA profile in the liver and muscle tissues were affected and reflected the dietary fatty acid composition to some extent. Tallow-based diets exhibited significantly higher levels of MUFAs (e.g., 18:1n-9) and reduced levels of SFAs than those fed the PBM + FO control diet. Muscle tissue of fish fed the PBM + TALLOW diet exhibited significantly lower levels of DHA and EPA than that fed PBM + FO diet. However, DHA supplementation partially corrected this effect by enhancing DHA content in muscle. The magnitude of LC-PUFA “sparing effect” in the present study was limited due to the elevated levels of dietary 18:2n-6 from the PBM that accumulated in the muscle tissue in the extent of the LC-PUFAs. In summary, the current results provide valuable insights regarding dietary DHA in juvenile totoaba towards formulating fish oil-free diets. Dietary PBM and beef tallow successfully replaced FO in the context of production performance and overall blood parameters. DHA supplementation was beneficial for enhancing the levels of this human health-promoting fatty acid in the muscle tissue. Also, it might increase fish performance reducing the need of using fish oil in aquafeeds. We suggest that towards fish oil-free aquafeed formulations it is essential to balance the dietary fatty acids. Concomitant to this fact, it will be necessary to reduce the lipid content in PBM to facilitate feed formulation.

Growth Performance and Feed Utilization of Low-Cost Artificial Feeds for Juvenile Asian Horseshoe Crab Culture

ABSTRACT A feeding experiment was undertaken for 84 days to investigate the growth performance and the feed utilization of two horseshoe crab species from partial replacement of fish meal (FM) with blood meal (BM), meat and bone meal (MBM), and poultry by-product meal (PBM) in their diet. Triplicate groups of Tachypleus tridentatus or Carcinoscorpius rotundicauda were fed nine isonitrogenous (digestible protein 40%) and isoenergetic (digestible energy 14 MJ kg-1) diet treatments. For both species, the growth performance, that is, final individual body weight and thermal-unit growth coefficient (TGC), and feed utilization, that is, including feeding rate (FR) and feeding efficiency ratio, of the juveniles fed with PBM and MBM at 2:1 ratio were higher than those of juveniles fed with diets containing PBM and MBM at 1:1 ratio at the same FM replacement level. Final individual body weight, TGC, and FR of the two species fed with the 100% FM replacement diets were significantly lower than in other diet treatme...

Prediction of apparent protein digestibility by in vitro pH-stat degree of protein hydrolysis with species-specific enzymes for Siberian sturgeon (Acipenser baeri, Brandt 1869)

In the present study in vivo apparent protein digestibility (APD) and in vitro degree of protein hydrolysis (DPH; pH-stat assay) of numerous feed ingredients (n = 10) were investigated in juvenile Siberian sturgeon (290 ± 22 g). The ingredients included: fish meal (FM; Clopeonella), meat and bone meal (MBM), poultry by-product meal (PBM), spray dried blood meal (BM), feather meal (FeM), solvent extract soybean meal (SBM), canola meal (CM), corn gluten meal (CGM), wheat gluten meal (WGM), and bakers' yeast (BY). APD values of the ingredients varied from 60 to 92.9% (feather meal and fish meal, respectively). APDs lower than 70% were found in blood meal (68.5%), soybean meal (66.2%), bakers' yeast (66%), canola meal (61%) and feather meal (60%). Also, the ingredients indicated APD values higher than 70%; corn gluten meal (74.3%), wheat gluten meal (76.9%), poultry by-product meal (83.1%) and meat and bone meal (85.6%). Higher DPH values (> 5%) were observed for fish meal, poultry by-product meal and wheat gluten meal; mid-range DPH values (3–5%) for corn gluten meal, meat and bone meal, soy bean meal, blood meal, bakers' yeast; and lower DPH values (<2%) for canola meal and feather meal. Linear regressions between in vivo APD and in vitro degree of DPH with enzyme extracts in feed ingredients for Siberian sturgeon resulted in a considerable correlation (R2 = 0.89–0.99). Also, linear regressions between APD and DPH suggested a close relationship between peptide bond breakage by pyloric caeca and intestine digestive enzymes and the ADP. As a result, this may be a useful tool to provide important nutritional information.

Comparative effect of advanced soy products or corn protein concentrate with porcine meal on growth, body composition, and distal intestine histology of Florida pompano, Trachinotus carolinus

The present study was designed to investigate the effects of diets containing advanced soy products (enzyme‐treated soy and fermented soy) or corn protein concentrate (CPC) in combination with porcine meal (PM) to completely replace poultry byproduct meal (PBM) on growth performance, body composition, and distal intestine histology of Florida pompano, Trachinotus carolinus. Four experimental diets were formulated to be isonitrogenous and isolipidic, to contain 400 g/kg crude protein and 80 g/kg lipid. A reference diet (PBM diet [PBMD]) contained 150 g/kg PBM and 495 g/kg soybean meal (SBM), and three test diets were formulated replacing PBM with 15 g/kg of CPC (CPC diet [CPCD]) or replacing all SBM and PBM with 535 g/kg fermented soy (fermented soybean meal diet [FSBMD]) or 451.3 g/kg enzyme‐treated soy (enzyme‐treated soybean meal diet [ESBMD]). All three test diets were supplemented with 38 g/kg of PM. Diets were fed based on a percentage of bodyweight adjusted after sampling the fish every 2 weeks to triplicate groups of Florida pompano juveniles (mean weight 8.06 ± 0.22 g). After 8 weeks of feeding, fish fed CPCD and ESBMD performed equally well in terms of final body weight, thermal growth coefficient, and percentage weight gain in comparison to fish fed PBMD. In all cases, feeding FSBMD resulted in poor feed conversion and lower feed intake compared to other treatments. Protein retention efficiency, whole‐body proximate composition, phosphorus, sulfur, potassium, magnesium, calcium, sodium, and zinc contents were not significantly influenced by the dietary treatments. The results obtained in the present histological study showed no significant differences in the thickness of serous layer, muscular layer, and submucosal layer of the intestine among treatments. Fish fed CPCD showed a significant widening of the lamina propria with an increase of cellular infiltration and higher presence of goblet cells compared to other dietary treatment. Based on these results, 451 g/kg ESBM or combination of 150 g/kg of CPC and 495 g/kg SBM supplemented with 38 g/kg PM can be utilized to develop a practical diet for juvenile Florida pompano without impacting growth, nutritive parameters, and several distal intestine health parameters.