Complete Replacement Of Fish Meal Research Articles

Morphometric evaluation of changes in the digestive tract of rainbow trout (Oncorhynchus mykiss) due to fish meal replacement with soy protein concentrate

Effects of the complete replacement of fish meal (FM) by soy protein concentrate (SPC) in high-energy diets (23 MJ kg−1 gross energy) on intestinal and liver histology were investigated in rainbow trout (Oncorhynchus mykiss). We developed a novel morphometric method to quantify the changes at the macro- and micromorphology level. Fish were acclimatized to the diet for 90 d and were then fed 1.0 g kg BW−1 d−1 once per day for 14 d before 10 fish per diet were randomly sampled, 6 h after their last meal. Fold height, epithelium length, stroma proportion of the proximal and distal intestines were not affected by the diet. No significant diet effect was detected on the features of the valve in the distal intestine. Fold height was linked to epithelium length in the proximal and distal intestines and this relationship was not modified by FM replacement. Enterocyte height and width were lower in SPC-fed fish in the distal intestine, but in the proximal intestine their morphology was not affected by the diet. There was no diet effect on the number of cells infiltered between the enterocytes in the proximal and distal intestines. The enterocyte nucleus was closer to the apex in the proximal and distal intestines in SPC-fed fish, but the features of the nucleus were not affected by the diet. The mean hepatocyte volume was on an average 36% lower in SPC-fed fish and was positively correlated to the hepatosomatic index for fish fed this diet only. In conclusion, SPC used in the present study did not either cause inflammatory reaction of the gut nor affected the epithelium surface. We suggest that the modifications due to SPC are linked to variations in the metabolic status of the enterocyte.

Partial and complete replacement of fish meal by broad bean meal in feeds for Nile tilapia, Oreochromis niloticus, L., fry

A 16-week feeding experiment was conducted to study the feasibility of using broad bean meal (BBM) as a replacement for fish meal (FM) for Nile tilapia Oreochromis niloticus fry, initial average weight 1.9±0.18 g. FM (50% of the diet) was used as sole sources of animal protein in the control diet 1. The replacement levels of BBM in diets (2–5) were 25%, 50%, 75% and 100% of the FM. Methionine (1%) and lysine (0.5%) were added to each diet except the control diet. Three groups of fish were fed each of five isonitrogenous (31.2% CP) and isocaloric (20.1 kJ g−1), and performance was compared against a nutritionally balanced control diet at the end of the experiment. Nile tilapia fed the diet containing 50% BBM exhibited comparable growth with those fed the FM-based control diet. Digestibility of protein, energy and lipid decreased with increasing levels of BBM above 50% of total replacement FM into the diet. Incorporation of BBM in the diets significantly affected the moisture, fat and energy of whole fish body. These results suggest that BBM can replace 50% of the FM in diet for Nile tilapia fry, without adverse effects on fish performance.

Complete Replacement of Fish Meal by Soybean Meal with Dietary L‐Lysine Supplementation for Nile Tilapia Oreochromis niloticus (L.) Fingerlings

AbstractThe effect of complete replacement of fish meal by soybean meal (SBM) with the dietary L‐lysine supplementation in prepared diet was studied in Nile tilapia fingerlings. Five isonitrogenous (33.2% crude protein) and isocaloric (4.8 kcal gross energy/g of diet) diets were formulated. Diet 1 was similar to a high quality commercial tilapia diet, containing 20% fish meal and 30% SBM. Diets 2–5 contained 55%, 54%, 53%, and 52% SBM and 0.5%, 1.0%, 1.5%, and 2.0% L‐lysine supplementation, respectively. After 10 wk, there was a significant difference in the final individual weight, final body length (cm), weight gain (%), specific growth rate (SGR), feed conversion ratio (FCR), protein effkiency ratio (PER), and food intake among flsh groups (P≤ 0.05). The best bal individual weight, final individual length (cm), weight gain (%), specific growth rate, feed conversion ratio, protein efficiency ratio (PER), and food intake were recorded in fish fed diet 2, which contained 55% SBM and 0.5% L‐lysine. There was a significant difference between it and diet 1 (control). Moisture in fish flesh was not significantly different (P > 0.05) among treatments and averaged 75.13%, while percentage protein was significantly dltrerent (P≤ 0.0% and the best result was achieved in flsh fed diet 2 and diet 1 (control). The highest values of digestibility coefficients of protein, fat and energy were recorded in groups of fish fed diet 2. These suggest that a diet with 55% SBM supplemented with 0.5% L‐lysine can totally replace fish meal in a diet for Nile tilapia fingerlings, without adverse effect on fish performance.

Evaluation of Sun-Dried Water Fern, Azolla africana and Duckweed, Spirodela polyrrhiza in Practical Diets for Nile Tilapia, Oreochromis niloticus Fingerlings

Two aquatic plants: water fern, Azolla africana and duckweed, Spirodela polyrrhiza were evaluated as feedstuffs in production diets for Nile tilapia, Oreochromis niloticus fingerlings. Eleven diets (30% crude protein) containing fish meal protein substituted at a rate of 5, 10, 20, 30, and 100% for either of the plant ingredients were formulated. A diet without any of the plant ingredients served as the control. Nile tilapia fed diets containing duckweed showed superior growth performance. There were no significant differences (P > 0.05) in growth responses of fish fed either 10% duckweed and 5% water fern dietary inclusion or the control diet. There was a growth depression in fish with increased dietary inclusion of both plants. The most cost-efficient diet was obtained in a diet with 30% duckweed dietary inclusion. Results of this study indicated that duckweed and water fern could be substituted for fish meal protein up to 10% and 5%, respectively, in low-cost diets for Nile tilapia without compromising growth. However, complete replacement of fish meal or soybean meal by water fern or duckweed decreases growth rates and should not be used in tilapia diets.

Growth performance of two Indian major carps, catla [formula omitted] and rohu [formula omitted] fed diets containing different levels of Spirulina platensis

The influence of Spirulina platensis meal on the growth and carcass composition of two Indian major carps, catla, Catla catla and rohu, Labeo rohita was investigated in a 90-day culture trial. Four experimental diets were used and Spirulina replaced fish meal protein from the standard diet at 25%, 50%, 75% and 100% levels. There was no significant difference in the final weight attained by catla at all levels of Spirulina incorporation as compared to the fish-meal-based control diet. However, the replacement of fish meal by more than 25% Spirulina resulted in significantly superior growth of rohu. The specific growth rate and protein efficiency ratio recorded in rohu improved with higher levels of Spirulina inclusion, while in catla they did not differ significantly from the control treatment. In both the species, the digestibility of dry matter, protein and fat was found to improve marginally with increasing levels of Spirulina incorporation. The carcass composition showed an inverse relationship between protein and fat deposition. In general, fish fed with Spirulina diets had a significantly higher percentage of fat. The study demonstrated the usefulness of Spirulina for partial or complete replacement of fish meal in the diets of catla and rohu.

Preliminary studies on the complete replacement of fishmeal by house-fly-larvae-meal in weaner pig diets: Effects on growth rate, carcass characteristics, and some blood constituents

Ten Large White weaners with an average liveweight of 10.6 kg were assigned to two diets containing either fishmeal or house-fly-larvae-meal as the main protein source. The average daily gains of the pigs were 0.25 and 0.29 kg for the fishmeal and house-fly-larvae-meal diets, respectively. Feed conversion ratios were 3.64 and 3.29, and feed cost per kg gain were ¢2735.18 and ¢2470.89 for the fishmeal and house-fly-larvae-meal diets, respectively. Dressing percentage, fat measurements, and eye muscle area were not significantly affected (P

Further results of complete replacement of fish meal by means of poultry by-products meal in feed for trout fry and fingerling (Salmo gairdneri).

By further experiment lasting 44 days trout fingerlings were fed with feed containing 50% poultry by-products meal in order to prove the possibility of using it as sole source of animal protein. Water temperature was 10-15 degrees C. The daily weight gain amounted to 2.17% with a feed conversion of 1.62 kg feed/kg gain. The control group being fed with standard feed (FB) containing 51.5% fish meal reached a daily weight gain of 2.33% with a feed conversion of 1.39 kg feed/kg gain. Due to higher lipid content of test diet the test group reached a higher fat content than the control group (10% compared to 5.9%). Suggested recipe makes it possible to use poultry by-products meal in pelleted feed for trout fingerlings.

Partial and complete replacement of fishmeal by soybean meal in feeds for intensive culture of carp

Feeding experiments with carp were performed in plastic tanks, in cages and in experimental ponds, using pelleted rations of 25% total crude protein. Fishmeal was the only source of supplemental protein in the control ration, besides the basal ground grains. Partial replacement (40% of the fishmeal) by soybean meal in pond trials required only supplements of methionine and 5% oil in order to attain the same growth, protein and energy utilisation as with the control ration. When most or all of the fishmeal was replaced by soybean meal, supplements of methionine, 0.4–0.5% lysine and 10% oil were necessary to achieve gains, protein efficiency ratio (PER), net protein utilization (NPU), protein retentions and energy retentions equal to those of the control fishmeal ration. It was concluded that regular soybean meal contains 10–15% less available energy and 10–15% less available lysine for carp than the generally accepted values (as in NRC-NAS, Nutrient Requirements of Poultry, 1977).