Preparation of fish waste silage and its effect on the growth performance and meat quality of broiler chickens

Recycling of animal protein wastes in the formulation of feed for Labeo rohita and Mystus vittatus-a comparative evaluation

Lactic acid bacteria (LAB) are key players in the fermentation of organic wastes and their recycling as feedstuff for fish. Whey, a common dairy byproduct in India, is a cheap source of LAB and can be used to ferment animal byproducts. An experimental study was designed to explore whether the whey fermented animal protein blend (WFAPB) could be used as a fishmeal replacer in the formulation of feed for both stomach-less carp fish Labeo rohita and stomach-bearing catfish Mystus vittatus. Experiments were performed with five isoproteinous, isolipidous, and isoenergetic feeds with WFAPB replacing fishmeal (FM) by 0% (T1), 25% (T2), 50% (T3), 75% (T4), and 100% (T5). Fifteen days of laboratory experiments with these experimental feeds revealed that more than 50% FM replacement level could result in excess postprandial absorption (6 h) of some essential and non-essential amino acids in the plasma of both fish. The postprandial absorption was more in M. vittatus than L. rohita. Ninety-day experiments were conducted in outdoor cement vats to measure growths and deposition of amino acids (AA) in muscle. Regression analysis was performed to find the optimal FM replacement based on four growth parameters and fifteen AA deposition in muscle. A two-phase fuzzy methodology was used to obtain Pareto-optimal replacement levels for each fish. The results demonstrated that FM replacement levels were 7.63% and 36.79% respectively for L. rohita and M. vittatus when only four growth parameters were considered. However, based on the FM replacement level that maximized deposition of 15 amino acids and growth parameters, it was found that 12.23% and 40.02% replacement of FM by the WFAPB was ideal respectively for L. rohita and M. vittatus. The results revealed that only a fraction of both essential and non-essential amino acids absorbed in plasma could be converted into protein and deposited as bound amino acids in the muscle. It is concluded that fermentation by whey is an inexpensive, easily available, and environmentally sustainable technique to recycle animal protein in the formulation of feed for fish, and the stomach-bearing carnivorous fish are more efficient in utilizing fermented animal protein blend than the stomach-less carps.

Synergism of fermented feed and ginseng polysaccharide on growth performance, intestinal development, and immunity of Xuefeng black-bone chickens

Microbial fermented feed (MF) is considered a valuable strategy to bring advantages to livestock and is widely practiced. Oral supplementation of Ginseng polysaccharide (Gps) eliminated weight loss in chickens following vaccination. This study investigated the effects of the combined use of Gps and MF on growth performance and immune indices in Xuefeng black-bone chickens. A total of 400 Xuefeng black-bone chickens at the age of 1 day were randomly assigned to four groups. Normal feed group (Control group), ginseng polysaccharide (200 mg/kg) group (Gps group), microbially fermented feed (completely replace the normal feed) group (MF group), and microbially fermented feed and add ginseng polysaccharide just before use (MF + Gps group). Each group contained 5 pens per treatment and 20 birds per pen. The body weight and average daily gain in the Gps, MF, and MF + Gps groups increased significantly (P < 0.01), while the feed conversion ratio decreased significantly (P < 0.01). The combined use of MF and Gps showed a synergistic effect. There was no significant difference in villus height (cecal) between the experimental group and the Con group. The crypt depth of the three experimental groups exhibited a significantly lower value compared to the Control group (P < 0.05). The V/C ratio of the Gps group and MF + Gps was significantly increased (P < 0.05), but there was no significant difference in the MF group. Moreover, the diarrhea rate of the Gps and the MF + Gps groups was lower than that of the Con group, while that of the MF + Gps group decreased the mortality rate (P < 0.05). The serum tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6) levels in the MF, Gps, and MF + Gps groups decreased significantly (P < 0.01), the serum immunoglobulin G (IgG) levels increased significantly (P < 0.01), while the combination of MF and Gps had a synergistic effect. The combined use of Gps and MF not only further improved growth performance and immune parameters, but also reduced the diarrhea rate and mortality.

Effects of a new generation of fish protein hydrolysate on performance, intestinal microbiology, and immunity of broiler chickens

This study was conducted to evaluate the effects of co-dried fish protein hydrolysate (CFPH) on broilers performance, intestinal microbiology, and cellular immune responses. Five hundred one-day-old (Ross 308) male broilers were allocated to four treatments with five replicates of 25 birds in a completely randomized design. The experimental treatments included four levels of CFPH (0% as the control, 2.5%, 5%, and 7.5%) in the isonitrogenous and isocaloric diets. During the experiment, body weight (BW) and feed intake (FI) were periodically recorded in addition to calculating average daily gain (ADG), feed conversion ratio (FCR), liveability index, and European broiler index (EBI). In addition, cellular immune responses were evaluated at 30 days of age. On day 42, ileal contents were obtained to examine the microbial population. Based on the findings, Dietary supplementation of 5 and 7.5% CFPH increased the percentage of the thigh while decreasing the relative weight of the gizzard compared to the control group. The highest relative length of jejunum was observed in birds receiving 2.5 and 5% CFPH, and its highest relative weight belonged to birds fed with 5% CFPH. The number of coliforms, enterobacters, and total gram-negative bacteria in the intestines of birds receiving CFPH was less than that of the control group. In general, the application of CFPH in broiler nutrition can decrease the level of soybean meal in diet and it can be considered as a new protein supplement in poultry production. It is suggested to study the incorporation of this new supplement in other livestock's diets.

How is fish market waste managed in the Philippines?

Improper management of fish waste is one of the factors that makes Philippine fisheries unsustainable. A considerable portion of fish waste is produced in wet markets where bulk of fish products are sold. A comparison of existing practices in different municipalities can indicate the best points of intervention and identify existing traditional practices that can be promoted. This study interviewed stakeholders of the fisheries industry and collected information at the market level to determine existing fish waste management systems. From the responses gathered, the average daily production of fish waste in Philippine wet markets was 70.3 + 0.93 kg, with no significant differences across locations (p = 0.2501). Of the fish waste produced, 32.3 + 1.33 kg per wet market were disposed of, 18.9 + 0.81 kg were sold, and 19.1 + 1.15 kg were given away to stakeholders who re-use the fish waste. A significantly greater proportion of fish waste in rural areas were re-used compared to Metro Manila (p = 0.0311). Incentivizing innovations that maximize the use of derived fish waste at the municipal level, and promoting existing traditional practices, can prove effective in contributing to the Philippine circular economy while providing alternative sources of income for the stakeholders of the fisheries industry.

Seafood Waste Management Status in Bangladesh and Potential for Silage Production

Frozen shrimp and fish are the second most valuable export items from Bangladesh. Thus, in processing industries, a considerable amount of seafood waste is produced every year. Neglecting seafood waste leads to serious forms of wastage. The purpose of this survey-based study was to estimate the amount of seafood waste produced and understand the existing waste management practices in Bangladesh. Potential for seafood waste-based silage production and its utilization were also studied. Across the seafood industry, around 43,321 tons of seafood waste are produced every year. The highest amount of seafood waste is produced in Khulna, followed by Chittagong, Cox’s Bazar, Dhaka, and Sylhet. Local people consume a portion of fresh shrimp carapace and heads and gills of large fish. A portion of seafood waste is also used to feed aquaculture species. Moreover, parts of dried shrimp shells, appendages, and fish scales, air bladders, and fins are exported to some Asian countries. The prospect of fish silage production constitutes a promising new development for animal feed production in Bangladesh. The availability of waste materials from seafood processors and the demand from feed millers favor the conditions for silage production. However, in order for the seafood waste-based silage industry to flourish, the establishment of supply chains for seafood waste and end products (silage) is required. Studies on growth performance, muscle quality, and digestibility of animal feed with silage-based diets are required for farmed species.

Inclusion of fish waste silage in broiler diets affects gut microflora, cecal short-chain fatty acids, digestive enzyme activity, nutrient digestibility, and excreta gas emission

A study was conducted to determine the impacts of dietary inclusion of fish waste silage (FWS) substituting soybean meal (SBM) on the performance, gut microflora, cecal short-chain fatty acid, apparent ileal digestibility (AID), digestive enzyme activity, and excreta noxious gas emission in broiler chickens. A total of 720-day-old male broilers (Cobb 500) were randomly allocated to 3 dietary treatments with 12 replicates each accommodating 20 birds for 42 d. Birds received diets as follows: a corn-SBM-based diet (CON) and 2 diets that replaced SBM with FWS at 60 g/kg (FWS60) and 120 g/kg (FWS120). During the entire period, replacing SBM with FWS60 and FWS120 increased body weight gain and decreased feed conversion ratio (P < 0.05). The lowest pH values in the crop, proventriculus, duodenum, ileum, and ceca were observed in birds fed diets containing FWS60 and FWS120 (P < 0.05). Likewise, birds fed FWS60 and FWS120 had lower numbers of coliform and E. coli and higher Bifidobacterium and Lactobacillus count in the ceca than those fed CON (P < 0.05). Feeding FWS60 and FWS120 diets increased cecal butyrate and lactic acid contents (P < 0.05). Birds fed FWS120 diets had greater intestinal amylase and protease activity than birds fed CON (P < 0.05); however, no significant differences were recorded between the treatment groups for digestive enzymes activity in the pancreas. The use of both levels of FWS in broiler diet increased AID of crude protein and ether extract (P < 0.05). The lowest excreta ammonia concentration was recorded in birds fed FWS120 diet (P < 0.05). In conclusion, the inclusion of FWS in broiler diets could improve the performance by enhancing gut function, derived from the improved digestive enzyme activity and nutrient digestibility, as well as by elevating the population of beneficial bacteria and short-chain fatty acid contents. Therefore, the biological silage can be considered as a promising option for recycling and recovery of fish wastes and effectively be used in broiler diets.