Evaluation of babassu meal in feed for layer hens during the growth phase

Studies were conducted to evaluate the nutritional value and inclusion levels of babassu meal (BM) in the diet of grower layer pullets in substitution to wheat meal. Digestibility, metabolism and growth trials were conducted. Twelve cecectomized roosters were used in the digestibility assay to determine the coefficients of standardized digestibility of amino acids (CSDAA). The metabolism trial was conducted with 30 adult roosters to determine the apparent metabolizable energy corrected for nitrogen (AMEn) of BM. A growth trial was performed to determine replacement levels of wheat midds by BM diet using 360 six-week-old commercial layer pullets. BM was included at the 0, 75 and 150 g/kg of BM, during grower and development rearing phases, respectively. Feed intake, body weight gain, and feed conversion were evaluated. BM AMEn was determined as 1,474 kcal/kg, on as-fed basis. The CSDAA determined for BM were below 88% for all AA. The inclusion of BM in the feed of grower layers (7-18 week) significantly decreased feed intake (p < 0.05), but significantly improved body weight gain and feedconversion ratio (p < 0.05) at 15% inclusion level. Considering the nutritional value and performance results, BM can replace wheat midds in diets of grower layer pullets.

Growth responses and yield of heterotis (Heterotis niloticus) on artificial diet

The growth responses and yield of Heterotis niloticus on artificial diets of varying protein levels were studied in a bid to assess the implication of feeding Heterotis in intensive fish production venture for a rearing period of 84 days. One hundred and twenty juvenile H.niloticus were fed for 12 weeks on 28%, 31%, 34% and 37% dietary crude protein levels. The fish were reared in 4 concrete tanks stocked at the rate of 10 fish per M super(2) 100,00/hectare). Consequently, the weight gain, food conversion ratio, serum protein and albumin-globulin ratio were determined to assess the growth and state of health of the fish. The yield was appraised through economic considerations of cost of production of fish and diets (feed). The varying crude protein levels significantly influenced mean weight gain, percentage weight gain and food conversion ratio however, the 37% crude protein in diet produced the best growth. The serum protein was highest in fish raised on 31% crude protein diet while the highest value was recorded for albumin-globulin ratio on diet containing 34% crude protein. The yield from treatments 1, 2, 3, and 4 were 114.38 of/84 days 571.9kg/g hect);146.79g/84 days 733.95kg/hect), respectively. However, treatment 3 recorded the highest value for profit index

Effects of fish-meal, cow blood-meal, and sorghum diets on food utilization and growth of cage cultured Sarotherodon niloticus

The growth responses and feed utilization of Sarotherodon niloticus held in metal cages in a pond and fed diets containing fish-meal, cow blood-meal or sorghum was studied. Results indicate that the best growth, feed conversion and protein efficiency ratio were obtained with the diet containing 60% fish-meal. The growth performance of fish on 40% fish-meal, and 40% and 60% blood meal were not significantly different, and were quite close to the performance with 60% fish-meal. The growth and food utilization of fish on 84% sorghum diet was significantly lower than the rest. The Caged fish without supplemental feeding had a light gain in weight. All fish with supplemental feeding appeared healthy. It is concluded that cow blood meal at 40% or 60% inclusion in diet can adequately replace fish-meal in S. niloticus supplemental diet in pond culture

The effect of replacement of soyabean meal with blood meal on the growth of mudfish Clarias anguillaris (L) fingerlings

Blood meal and full fat soyabean meal were mixed in different proportions to give 0%, 10%, 25%, 50%, 75%, 90% and 100% meal in the protein fraction of the diet and fed to Claria anguillaris fingerlings in floating hapas. The growth performance of the fingerlings were monitored for 84 days. At the end of the experiment the mean weight of the fingerlings increased in the level of blood meal up to 50% blood meal in the diet after which there was a decline in the mean weight of the fish. This same level of blood meal gave the best specific growth rate, feed conversion efficiency and protein efficiency ratio. Thus the nutritive value of blood meal was enhanced by the addition of an equal level of full fat soyabean meal in the diet

Growth performance of Heteroclarias fed maggot meal at varying inclusion levels

70-day growth trial was conducted with Heteroclarias: Heterobranchus bidorsalis X Clarias gariepinus (mean weight 0.64~c0.006g) fed diets based on various inclusion levels of Maggot Meal. The fishmeal in the control diet was replaced with maggot meals at 25%, 50%, 75% and 100% levels to supply 40% crude protein in the final diets. The trails were conducted in glass tanks (60cmx30cmx30cm). Evaluation of growth parameters and nutrient utilization of the fish was based on weight gains, protein intake, protein efficiency ratio, net protein utilization, feed conversion efficiency and carcass analysis. Best growth and feed conversion efficiency were obtained with the 75% dietary inclusion of maggot meal. There was no significant differences (P>0.055) between the group of fish on 50% and 75% dietary inclusion maggot meal in growth performance and protein efficiency ratio but, there was a significant (P<0.05) difference in the NPU (Net Protein Utilization) and protein gain between the control diet and those fed on maggot meals. There was no marked variation in the survival rate of fish on all diets

The effect of feeding rate on the growth, food conversion and protein efficiency of silver dollar, Metynnis schreitmulleri (AHL), fry

A 30-day experiment was conducted to determine the effects of varying feeding rates on the growth of fry of silver dollar, Metynnis schreitmulleri (Ahl). Silver dollar fry with an average initial body weight of 1.100 ± 0.029 g were collected from a local fish breeder and fed a diet (35% protein and 6% fat) at the rate of 3, 6 and 9% of body weight per day in two equal meals. Per cent weight gain increased from 54.54 to 118.18 with increased feeding rates, which were significantly different (p<0.05) from each other. The highest specific growth rate was obtained in the fry fed at 9% body weight per day. In another study for 30 days, the effects of feeding frequency on growth, feed conversion and protein efficiency of silver dollar fry were evaluated. Groups of silver dollar fry with an initial individual weight of 0.700 ± 0.019 g were offered feed continuously for 24 hours during the day or night at different time intervals with varying meal sizes. The night time feeding with two meals gave the lowest weight and length gains (0.985 g and 0.30 cm). The growth rates of fish fed during day with three equal-sized meals are significantly (p<0.05) higher (4.66%) than the other treatments.

Growth of juvenile freshwater prawn Macro brachium mslcolmsonii fed with various protein diets containing different biowastes

An experiment was conducted with juvenile prawns Macrobrachium malcolmso11ii, (0:76± 0.01 ro 0.94-::tO.Ol g) w evaluate various protein source diets. Six diets containing 20%, 25%, 30%, 35%, 40%,and 45% of crude protein were formulated, and fed to prawns in the form of pellet to evaluate their suitability. The experiment was designed for 60 days and sampling was made at every 15 days interval. At the end of the study period growth, feed conversion ration (FCR) specific growth rate (SGR), feed efficiency and survival were determined for prawns in each dietary treatment. Among the above five feeds poor FCR and higher weight gain observed in 35% protein diet (B-4). Similarly specific growth rate and feed efficiency are also highest with diet containing 35% protein. The dietary protein levels above 35% exerts a decrease in growth of prawn was observed in the present study. The feed efficiency ratio and protein efficiency ratio decreased with the increased dietary protein levels. It is concluded that 35% protein diet could be suitable with optimum protein supply for Macrobrachium malcolmsonii Therefore, above and below this 35% protein level in the formulated feed leads to metabolic stress which lowers the conversion efficiency and wastage of nutrients.

Feed utilization and wastage in semi-intensive pond culture of mahseer, Tor putitora. (Ham.)

Mahseer, Tor putitora with 12.75, 12.11, and 12.02g of initial weight were fou · J to attain a net weight gain of 12.0 kg, ll.5 kg, and 11.4 kg respectively in pond-1 (commercial feed), pond-2 (farm-made feed), and pond-3 (farm-made feed), respectively against 78.2 kg, 70.3 kg, and 68.1 kg feed fed. Gross energy contents in fish were 1359.3 Kcal/kg, 1281.5 Kcal/kg and 1266.6 Kcal/kg, respectively in pond-1, pond-2, and pond-3 against 3630.4, 3876.9 and 3570.5 Kcal/kg energy in the feed fed. Only 9.4%, 10.5% and 13.7% of the protein, and 8.9%, 3.4% and 3.3% of the lipid fed to fish were converted into muscle respectively in pond-1, pond-2 and pond-3. It was observed that the higher the protein content in feed, the lower the rate of conversion in muscle; the same was also true for lipid. It is supposed that feed derived wastes contribute potentially to water quality deterioration and eutrophication. Lower feed conversion, higher nitrogenous and phosphatic concentrations and higher plankton biomass in the ponds are all supportive to this observation.

Influence of stocking density on the culture potential of freshwater catfish Pangasius pangasius in pond

Influence of stocking density on the production of freshwater catfish Pangasius pangasius with formulated feed in ponds was studied. The fish fry were collected from the Meghna river near Chandpur which is a natural breeding ground of this fish. Three stocking densities chosen during this experiment were 5000, 8000 and 11000 fry/ha with an initial weight of 42.57 ±2.51 g. The formulated feed was prepared in the laboratory which contained 45% fish meal, 30% mustard oil cake, 15% wheat bran and 10% rice bran to supply 40.48% protein in feed. The growth of P. pangasius in terms of net weight gain was 409.49, 266.49 and 236.37 g at the 5000/ha, 8000/ha and 11000/ha stocking densities respectively, which was statistically significant (p<0.05). High food conversion ratio (FCR) was also observed during this research study which ranged between 7.06 to 7.72. A production of 2.6 tons/ha at the stocking density of 11000/ha; 2.13 tons/ha at the stocking density of 8000/ha and 2.04 tons/ha at the stocking density of 5000/ha was obtained, while the growth of individual fish at the end of experiment was in opposite order. The result of this experiment indicates that stocking density has significant influence on the culture potential of freshwater catfish P.pangasius.

Effect of salinity on food consumption and growth of juvenile Nile tilapia (Oreochromi niloticus L.)

The effect of salinity (0, lO and 20%o, water temperature 28 ± l oC) on food consumption and growth of juvenile Nile tilapia, Oreochromis niloticus L. (9.94 ± 0.15 g) were investigated by feeding group of 20 fish at 2% body weight day. Individual food consumption was measured using X-radiography. There were no significant differences in growth or white muscle protein concentrations among groups. During feed deprivation, weight loss was similar for fish held at O%o and 10 %o salinity, but after 7 days over 50% of the fish maintained at 20%o salinity developed lesions covering 5-25% of the body. No significant relationships were observed between individual specific growth rates and food consumption rates within the groups. The fish in all salinity groups showed a negative correlation between specific growth rate and food conversion ratio. The coefficient of variation for wet weight specific food consumption and the mean share of meal for each fish were used as a measure of social hierarchy strength. A negative correlation was observed between coefficient of variation in food consumption and mean share of meal. The social hierarchy structure was similar in all salinities; 25% of the fish were dominant (18.29% above an equal share of meal) and 30% were subordinate (16.19% below an equal share of meal) and the remainder 45% fish fed theoretical share of meal (MSM, 5.26%).

Growth and survival of Penaeus monodon postlarvae fed shrimp head meal and fish meal as primary animal source of protein

Although shrimp head meal alone does not provide for good growth and survival, fish meal can provide high survival rate. The addition of shrimp head improves this diet. It is suggested that cholesterol present in shrimp could have caused this difference. Composition of the test diets is tabulated, as are proximate chemical analysis of the diets, and the mean initial weights, final weights, weight gains, survival rate, feed consumed, protein consumed, of Penaeus monodon postlarvae, feed conversion and protein efficiency ratio.

A preliminary study on the evaluation of casein, shrimp meal, squid meal and spirulina as protein sources of Penaeus monodon (Fabricius) postlarvae

P. monodon postlarvae were fed with fresh brown mussel (Modiolus metcalfei ) meat, and artificial diets containing casein, shrimp (Metapenaeus ensis ) meal, squid (Loligo ) meal, and Spirulina as protein sources at a rate of 20% of their biomass per day for a period of 10 days. No statistical difference was found among the weight gains of shrimp fed on various experimental diets. However, shrimp fed squid meal diet had highest weight gain followed by shrimp meal, fresh brown mussel meat, casein and Spirulina . Shrimp fed squid meal diet had a significantly better feed conversion and those receiving other experimental diets. Poorest fed conversion was observed in shrimp fed Spirulina . The protein efficiency ratio was statistically highest for the squid meal diet, with the lowest value again for Spirulina diets. Survival rate was significantly highest for shrimp fed the shrimp meal diet. No statistical differences were found among shrimp fed other experimental diets. Appropriate data are tabulated.

Suitable stocking density of tilapia in an aquaponic system

An aquaponic system was studied through the integrated culture of mono-sex GIFT and two types of vegetables viz. morning glory, Ipomoea reptans and taro, Colocasia esculenta in a recirculating system for 15 weeks. Tilapia fry of uniform size of 0.76 g were released in three treatments (stocking densities): 106 fish/m³ (T1), 142 fish/m³ (T2) and 177 fish/m³ (T3) to assess the effect of stocking density on the growth performance of fish. Fish were fed with a commercial feed containing 25% protein. Weight gain (g) of tilapia ranged from 19.41 to 32.67 g and was inversely related with stocking density. Percent weight gain varied between 2553.99 and 4298.68% and was significantly different among the treatments. SGR ranged from 3.09 to 3.59% per day and varied significantly. FCR varied from 2.19 to 2.69 and had a positive correlation with stocking density. The highest survival rate (%) was achieved in T1 (99%) followed by T2 (98%) and T3 (96%). Production of fish ranged from 3.43 to 3.52 kg/m³ and was inversely related with stocking density. The present study demonstrated that 106 fish/m³ was the best stocking density in terms of growth, food conversion ratio, survival and production for tilapia culture in the aquaponic system.

Core design options for high conversion BWRs operating in Th- 233U fuel cycle

Several options of fuel assembly design are investigated for a BWR core operating in a closed self-sustainable Th-233U fuel cycle. The designs rely on an axially heterogeneous fuel assembly structure consisting of a single axial fissile zone "sandwiched" between two fertile blanket zones, in order to improve fertile to fissile conversion ratio. The main objective of the study was to identify the most promising assembly design parameters, dimensions of fissile and fertile zones, for achieving net breeding of 233U. The design challenge, in this respect, is that the fuel breeding potential is at odds with axial power peaking and the core minimum critical power ratio (CPR), hence limiting the maximum achievable core power rating. Calculations were performed with the BGCore system, which consists of the MCNP code coupled with fuel depletion and thermo-hydraulic feedback modules. A single 3-dimensional fuel assembly having reflective radial boundaries was modeled applying simplified restrictions on the maximum centerline fuel temperature and the CPR. It was found that axially heterogeneous fuel assembly design with a single fissile zone can potentially achieve net breeding, while matching conventional BWR core power rating under certain restrictions to the core loading pattern design. © 2013 Elsevier B.V. All rights reserved.

Axial discontinuity factors for the nodal diffusion analysis of high conversion BWR cores

High conversion LWRs concepts typically rely on a heterogeneous core configuration, where fissile zones are interspersed with fertile blanket zones in order to achieve a high conversion ratio. Modeling such a heterogeneous structure of these cores represents a significant challenge to the conventional reactor analysis methods. It was recently suggested to overcome such difficulties, in particular, for the case of axially heterogeneous reduced moderation BWRs, by introducing an additional set of discontinuity factors in axial direction at the interfaces between fissile and fertile fuel assembly zones. However, none of the existing nodal diffusion core simulators have the capability of accounting for discontinuity of homogeneous nodal fluxes in axial direction since the fuel composition of conventional LWRs is much more axially uniform. In this work, we modified the nodal diffusion code DYN3D by introducing such a capability. The new version of the code was tested on a series of reduced moderation BWR cases with Th-U233 and U-Pu-MA fuel. The library of few-group homogenized cross sections and the data required for the calculation of discontinuity factors were generated using the Monte Carlo transport code Serpent. The results obtained with the modified version of DYN3D were compared with the reference Monte Carlo solutions and were found to be in good agreement. The current analysis demonstrates that high conversion LWRs can in principle be modeled using existing nodal diffusion core simulators. © 2013 Elsevier Ltd. All rights reserved.