Department Of Marine Sciences

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https://ir.unilag.edu.ng/handle/123456789/3388
From its inception in 1962, the University of Lagos has been identified as a potential centre for the development of Marine Biology and Fisheries in Nigeria. At that time, it was the only University/ Institution in Nigeria situated by the sea and it was obvious that it was most suitable for the development of such disciplines. In the absence of a Faculty of Agriculture and taking full benefit of its location by the sea, lagoon and river, the University of Lagos is one of the very rare institutions in the world suitable for the establishment of a Marine Biology and Fisheries programme.

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Browsing Department Of Marine Sciences by Author "Aderolu, A. Z."

Now showing 1 - 16 of 16
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    Open Access
    ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF SOME NIGERIAN GREEN LEAFY VEGETABLES
    (Ethiopian Journal of Environmental Studies & Management, 2018) Edada, U. P. ;; Lawal, M. O. ;; Aderolu, A. Z.
    This study evaluated the antioxidant and antimicrobial properties of Piper guineense, Ocimum gratissimum, Murraya koenigii and Gongronema latifolium leave extracts using ethanol, petroleum-ether and aqueous media. The scavenging activities of the extracts was measured with free radical 2, 2-diphenyl-1-picrylhydrazyl, flavonoid and phenolic contents were assessed by spectrophotometry while, gas chromatographic flame ionization detector was used for phytochemical screening of the extracts. The micro-broth dilution and agar diffusion methods were used to assess Minimum inhibitory and bactericidal concentrations of the extracts respectively. The different leaves extracts differed significantly (P<0.05) at 25, 50, 75 and 100µg/ml of radical scavenging activities, with the lowest and highest values recorded at 25 and 100µg/ml respectively. The aqueous extract of G. latifolium had the highest value (67.60 ± 0.12mg GAE/100g DW) while, petroleum ether extract of P. guineense had the lowest value (30.65 ± 0.06mg GAE/100g DW) of total phenolic content. The highest and lowest flavonoid contents were found in petroleum ether extract of P. guineense (80.75 ± 0.37mg Rutin/g DW) and in aqueous extract of M. koenigii (36.27 ± 0.62mg Rutin/g DW). Phytochemicals screening indicated that the extracts were rich in steroids, terpenoids, tannins, saponins, phlobatannins, cardiac glycosides and alkaloids. The petroleum ether, ethanol and aqueous extracts were active against the growth of S. epidermidis, P. aeruginosa, K. pneumonia, E. coli, S. aureus, and S. typhimurium. This study proved that all crude extracts showed robust antioxidant and antimicrobial potentials which, could be harnessed for both their health and nutritional benefits in fisheries.
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    Open Access
    Biodegradable rice husks in laying bird's diet: Performance and egg quality parameters
    (Livestock Research for Rural Development, 2004) Iyayi, E.; Onilude, A.; Eniola, I.; Aderolu, A. Z.
    Rice husks were subjected to biodegradation using the fungus Trichoderma viridii, and included in traditional diets for laying hens at rates of 20, 30 and 40%; a diet with 20% undegraded rice husk was used as control. Biodegradation of rice husk led to improvements in nutritional composition (higher crude protein; less fibre) than the untreated material. However, there was no difference in feed intake or hen-housed egg production between the diets with undegraded or biodegraded rice husk at the 20% level. Increasing the level of biodegraded rice husk from 20 to 40% resulted in a linear decrease in egg production.
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    Open Access
    Changes in Nutritional Value of Rice Husk during Trichoderma viride Degradation
    (Bulgarian Journal of Agricultural Science, 2007) Aderolu, A. Z.; Iyayi, E. A.; Onilude, A. A.
    Possible improvement in nutritional status of rice husk using Trichoderma viride a fungus was investigated over a period of 40 days. Proximate composition was significantly (P<0.05) improved with microbial treatment except the ether extract, which fell on day 40. With the mineral content of the biodegraded samples, both the calcium and sodium contents rose, the only exception being the potassium content, which fell below that of the undegraded sample. Biodegradation also resulted in improvement in the energy content of the treated samples when compared to the untreated but no regular pattern was observed over the period studied. Significant reduction in the cell wall content of the rice husk was observed as the period of degradation increases. The least value for NDF and ADF was obtained on Day 40 while the least value for hemicelluloses was obtained by the 30th day.
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    Open Access
    Dietary Effects of Coconut Oil and Peanut Oil in Improving Biochemical Characteristics of Clarias gariepinus Juvenile
    (Turkish Journal of Fisheries and Aquatic Sciences, 2009-01-23) Aderolu, A. Z.; Akinremi, O. A.
    Attempt in reducing the high cost of feeding in aquaculture through the use of energy rich oils was taken as a means of protein sparing action. Juveniles of Clarias gariepinus with an average weight of 20.0±1.20 g were allotted at random, 5 fish per tank in a total of ten tanks and were fed five isocalorific and isonitrogenous diets containing 5% and 10% graded levels of coconut oil and peanut oil, respectively over a period of 6 weeks. Results obtained showed that fish fed diets containing graded levels of oil had significantly higher (P<0.05) weight gain, feed efficiency ratio and specific growth rate when compared to the control diet that had no oil. Among the oil diets, 5% inclusion level of peanut oil gave the highest feed and protein efficiency ratios (1.75 and 4.37, respectively). No significant difference was observed in weight gain, feed conversion ratio, and specific growth rate between fish fed 10% coconut oil and 10% peanut oil. The cholesterol level is lower in the control diet (198 mg/dl) compared to other diets with values ranging from 220-260 mg/dl. Carcass analysis shows no significant difference between the control diet and others in terms of the crude protein values; but the ether extract result of the carcass is significantly higher in the control compared to other diets (25.62>16.86). The lowest economic conversion ratio of 0.51 was obtained on the 5% peanut feed as compared to 0.73 for the control. Diet 1-4 which had graded level of oil had better ratios of feed conversion and economic conversion than the control without oil inclusion. Inferences from this study conclusively support the inclusion of graded levels of coconut and peanut oil in the diets of Clarias gariepinus for better growth and economic value in the sustenance of aquaculture.
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    Open Access
    Dietary effects of Sun- hemp (Crotalaria juncea Linn.) in the diet of African catfish, Clarias gariepinus juveniles
    (actaSATECH, 2012) Lawal, M. O.; Aderolu, A. Z.; Adeyemi, B.; Aarode, O. O.
    With an increasing interest in new feedstuff sources, the seeds of wild plants including the tribal pulses are receiving more attention, because of their high resistance to diseases and pests and in addition, they exhibit good nutritional qualities. The seed of Crotalaria juncea was used to replace soybean meal at 5%, 10%, 15%, 20%, 25%, 30% inclusion levels respectively and the control diet was set up without the test ingredient. C. gariepinus juveniles used for the experiment were fed to satiation thrice daily and their water was changed every other day. The weekly feed supplies and weight gains were recorded and used to compute the growth, nutrient utilization and the economic parameters. There were significant differences (P<0.05) in all the growth and nutrient utilization parameters examined. The highest average weight gain (AWG) was recorded in the control treatment (107.69+2.41g) while the least value (66.09+0.48g) was recorded in fish fed with D6 (30%). Similar patterns of results were observed in the other growth parameters as well as nutrient utilization parameters. The best values for Pin, ICA and ECR were recorded in diet 2 after the CTR compared with other dietary treatments. The packed cell volume, white blood cell and haemoglobin were significantly (P<0.05) higher in the control than other tests. Similarly, the control recorded significant (P<0.05) values in the proximate composition of carcass . Sun-hemp seeds do not have any adverse effect on haematological parameters, and carcass proximate composition of the fish. Furthermore, the cost analysis showed that more profit awaits the farmer if diet 2 (10% sun-hemp seed and 20% soy bean inclusion level) is adopted in addition to the medicinal values of the test ingredient.
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    Open Access
    Dietary effects of yam peels on the growth and haematology of Clarias gariepinus(Burchell, 1822) Juveniles.
    (The Zoologist, 2012) Lawal, M. O.; Aderolu, A. Z.; Ajayi, J. A.; Soyinka, O. O.
    This study investigated the growth performance, nutrient utilization and haematology of Clarias gariepinus juveniles fed with graded levels of yam peels (YMP). Replacement levels of 0 % (Control diet, CTR), 5 % (Diet 1), 10 % (Diet 2) and 15 % (Diet 3) for maize meal were tried. Feeds were fed to triplicate groups of ten fish per tank twice daily to satiation for eight weeks. Diet had effects (p<0.05) on Mean weight gain (MWG), Specific growth rate (SGR) and Mean voluntary feed intake (MVFI) across treatments. Fish fed with CTR recorded highest values for MWG (138.00±2.21g), SGR (2.12±0.01%) and MVFI (0.95±0.06g) while Diet 3 had least values for MWG (92.82±5.85g), SGR (1.69±0.06%) and MVFI (0.66±0.01g). Feed conversion ratio (FCR) and Protein efficiency ratio (PER) had significant differences (p<0.05) among the test diets, with the control diet having the highest values for FCR (0.95±0.05) and PER (2.32±0.13). Significant differences (p<0.05) were also recorded in the values of Packed cell volume (PVC), Red blood cells (RBC), Haemoglobin (Hb) and White blood cells (WBC) across diets. The poor growth performance coupled with reduced physiological activities of YMP at different inclusion levels tested, suggests that it could not favourably replace maize meal in the diet of C. gariepinus.
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    Open Access
    Effects of acute and sub-lethal concentrations of phostoxin on weight changes and haematology parameters of Clarias Gariepinus
    (Journal of Environmental Extension, 2008-01) Aderolu, A. Z.; Ayoola, S. O.; Agwu, K. I.
    Fish are sensitive to a wide variety of chemicals and toxic conditions. In aquatic environment, organophosphate may cause several physiological and biochemical defects in fishes. Clarias gariepinus (mean weight 10±0.1g) was exposed to acute and sub-lethal concentrations of phostoxin to evaluate the toxicity of phostoxin organophosphate. Effect of phostoxin on haematological parameters and weight changes of juvenile Clarias gariepinus was also investigated. The concentrations used during the acute toxicity test were 1.00, 2.0, 4.00, 6.00 mg/l with a control of 0.00mg/l; while the concentrations of the toxicant used during the 28-days sublethal exposure were 0.60, 0.40, 0.20 mg/l with a control of 0.00 mg/l. The lethal concentration (LC50) value of phostoxin was 2.20mg/l for 96h of exposure. The results obtained from the sublethal exposure showed that there was a progressive decrease in weight gain of fish as the concentration of the toxicant increased. Also, haematological indices indicated that the fish became hyperglycaemic and hypoproteinaemic and the severity of this condition were directly proportional to the phostoxin concentration. C.gariepinus is susceptible to phostoxin; therefore use of phostoxin in disinfection on/near fish farm or area close to aquatic environment should be discouraged.
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    Open Access
    Effects of graded activated charcoal in rice husk diets for mud catfish, Clarias gariepinus juveniles (Teleostei: Clariidae)
    (Iranian Society of Ichthyology, 2016-09) Aderolu, A. Z.; Lawal, M. O.; Adesola, T. T.
    This study investigated the growth performance, nutrients utilization and haematology of Clarias gariepinus juveniles fed with graded activated charcoal (AC) in rice husk (RH) diet. Eight diets were formulated; Control diet 1 (without RH and AC), Control diet 2 (+AC), Diet 3 (2.5% RH), Diet 4 (2.5% RH+AC), Diet 5 (5.0% RH), Diet 6 (5.0% RH+AC), Diet 7 (7.5% RH), Diet 8 (7.5% RH+AC). Diets were fed to triplicate groups of ten fish per tank thrice daily to satiation for eight weeks. Fish fed Diet 4 recorded highest values for mean weight gain (MWG) (75.71±1.76g), SGR (2.40±0.03%/day) and PER (3.22±0.15) while fish fed Diet 7 had the least values for MWG (59.50±1.21g), SGR (2.09±0.03g) and PER (2.39±0.10). The AFI did not record significant difference (P>0.05) while FCR had significant difference (P<0.05) across diets, with Diet 4 having the best value for FCR (0.86±0.04). Diets of RH lower cholesterol, PCV and Hb levels in the experimental fish though, the inclusion of AC to the test diets resulted in a nonsignificant increase in the levels of these parameters. The values of WBC and RBC did not show significant differences (P>0.05) amongst diets however, Diets 1 and 2 recorded the highest values for WBC (14500±707.11) and RBC (6.15±0.91) with the least values (9000±2828.43 and 5.15±0.21, respectively) for these parameters recorded with Diets 3 and 7. The improved growth recorded at 2.5% inclusion level of AC suggests that activated charcoal could favourably be added to the feed of C. gariepinus juveniles.
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    Open Access
    Evaluation of antimicrobial and antioxidant properties of some herbs used in sub-Saharan Africa, Nigeria
    (Journal of Coastal Life Medicine, 2017) Lawal, M. O.; Aderolu, A. Z.; Oke, A.
    To examine antimicrobial and antioxidant potentials of Cissus populnea (C. populnea) root and Securidaca longipedunculata (S. longipedunculata) leaf and root extracts using aqueous, ethanol and petroleum-ether media.The free radical 2,2-diphenyl-1-picrylhydrazyl was used to measure scavenging activities of extracts, while phenol and flavonoid contents were estimated by spectrophotometry and the antibacterial screening of extracts was done using disc diffusion method. The extracts were tested against five strains of Gram positive and negative bacteria. Minimum inhibitory concentration of extracts in the screening assay was according to micro-broth dilution, and minimum bactericidal concentration was carried out by agar diffusion method. The ethanol extract of the S. longipedunculata leaf recorded the highest [(83.00 ±2.97) μg/mL] radical scavenging potential while the least value [(48.50 ± 2.55) μg/mL] was recorded for C. populnea root ethanol extract. The highest phenol content was found in the ethanol extract of C. populnea [(145.60 ± 0.85) mg gallic acid equivalent/g], while the least value [(87.75 ± 3.46) mg gallic acid equivalent/g] was recorded in petroleum ether extract of S. longipedunculata. The highest and lowest values [(81.30 ± 0.99) and (46.60 ± 1.98) mg rutin equivalent/g] of flavonoid were recorded with ethanol extracts of S. longipedunculata leaf and root, respectively. The aqueous and ethanol leaf and root extracts of S. longipedunculata were active against the growth of Escherichia coli, Staphylococcus aureus, Vibrio cholerae, Pseudomonas aeruginosa and Salmonella typhi. Similar results were observed with ethanol and aqueous root extracts of C. populnea for the same bacteria. All the crude plant extracts possessed strong antioxidant and antimicrobial activities qualifying them as medicinal herbs that could be included in animal feed production.
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    Open Access
    Evaluation of soybean meal replacement with sesame seed meal using activated charcoal as an additive in the diet of African catfish juveniles, Clarias gariepinus
    (International Journal of Aquatic Biology, 2016-02-25) Lawal, M. O.; Aderolu, A. Z.; Aarode, O. O.; Seriki, B. M.; Timothy, O. A.
    This study evaluated the effects of 0.25% activated charcoal added to sesame seed meal (SSM) in partial replacement of soybean meal (SBM) of juvenile Clarias gariepinus diet on growth and haematological parameters for 70 day experimental period. Six experimental diets were formulated as: control diet 1 (100% SSM without activated charcoal), control diet 2 (100% SSM plus 0.25% activated charcoal), diet 3 (50% SMB+50% SSM), diet 4 (50% SBM+50% SSM+0.25% AC), diet 5 (30% SBM+70% SSM) and diet 6 (30% SBM+70% SSM+0.25AC). The inclusion of activated charcoal recorded significant improvement in mean weight gain, mean feed intake, specific growth rate (SGR), protein intake (PI) and protein efficiency ratio (PER). The control diet 2 recorded the highest values for growth and nutrient utilization parameters while diet 5 recorded the least values for these parameters. The best values for mean weight gain (65.33±5.57 g), specific growth rate (2.56±0.12% / day) and feed conversion ratio (0.71±0.05) were recorded in fish fed control diet 2 while the worst values (41.30±3.82 g, 1.92±0.11% / day, and 1.07±0.07, respectively) for these parameters were observed with diet 5. However, haematological parameters did not differ significantly across the diets. Thus, from this study 0.25% activated charcoal could favorably be added to the feed of C. gariepinus for optimum performance without any adverse effect on the health status of the fish.
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    Open Access
    Growth and economic performance of Clarias gariepinus juveniles fed diets containing velvet bean, Mucuna pruriens, seed meal
    (AFRICAN JOURNAL OF AQUATIC SCIENCE, 2009-04-14) Aderolu, A. Z.; Akpabio, M. V.
    The partial replacement of fishmeal with mucuna seed meal in the diet of cultured juvenile Clarias gariepinus was tested over 70 days to determine their growth, nutrient and economic performance. The 25% fishmeal component of the control diet was replaced with 5–15% raw or processed mucuna seed meal and the fish were fed twice daily at 5% of their average body weight per day. The diet containing 5% raw mucuna seed meal resulted in the best specific growth rate (2.42% d–1), feed conversion ratio (2.05) and protein efficiency ratio (1.34), as well as the highest net profit of US$0.065 per fish and the best benefit-cost ratio of 1.32. The diet containing 15% processed seed meal produced the worst results. The processing of mucuna seed resulted in improved crude protein and ether extract and a 20% reduction in crude fibre.
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    Open Access
    Growth and economic performance of Nile Tilapia, Oreochromis niloticus (L.) fingerlings fed diets containing graded levels of sclerotium
    (Aquaculture, Aquarium, Conservation & Legislation, International Journal of the Bioflux Society, 2013-01-19) Lawal, M. O.; Aderolu, A. Z.; Aarode, O. O.
    This study was conducted to evaluate the effects of inclusion of sclerotium as a substitute for soybean meal in the diet of Oreochromis niloticus using growth performance, economy of production, haematological and biochemical parameters as indices. Four experimental diets comprising of control (CTR) without sclerotium and other three diets SC1, SC2 and SC3 containing 7.5, 10.0 and 12.5 % sclerotium, respectively. The experimental diets were fed to triplicate groups of fish fingerlings (0.81± 0.00g average body weight) for 70 days. The inclusion of sclerotium at 7.5% level recorded the best values for mean weight gain (MWG), specific growth rate (SGR) and feed conversion ratio (FCR). There was no significant difference (p>0.05) in the incidence cost (IC) and profit index (PI) among the diets however, the best results were achieved at 10% (SC2) inclusion level. The parked cell volume (PCV), haemoglobin (Hb), neutrophil and lymphocyte showed significant difference (p<0.05) between CTR and other three diets while there was no significant difference (p>0.05) in eosinophil among the four diets. Biochemical parameters recorded significant differences (p<0.05) among the four diets. Hence, due to the nutritional and therapeutic characteristics of sclerotium, its inclusion in the diet up to 12.5% could be tolerated by O. niloticus.
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    Open Access
    Growth performance of Clarias gariepinus fingerlings fed graded levels of dietary cooked Jatropha curcas seed meal based diet
    (The Egyptian Society of Experimental Biology, 2016) Jimoh, W. A.; Aderolu, A. Z.; Oladele-Bukola, M. O.; Abdulsalami, S. A.; Okemakin, F. Y.
    The effect of dietar y inclusion of Jatropha curcas on the growth per formance of Afr ican Catfish (Clar ias gar iepinus) was evaluated. Juveni les of Clar ias gar iepinus 225 in numbers were accl imatized for a week, weighed and al lotted into five dietar y treatments where soybean meal was replaced by cooked Jatropha curcas seed meal at 0, 25, 50, 75 and 100%. The diets (40% crude protein and 12% crude l ipid) were isoni trogenous and isol ipidic. Each treatment was repl icated three times wi th fi fteen fish per repl icate. Fish were fed 5% body weight on two equal propor tions per day for 56 days. Growth data were col lected on two-week interval basis. Growth per formance was evaluated usingweight gain (g) ; speci fic growth rate (%/day) ; feed conversion ratio (FCR) and protein efficiency ratio as indices. The resul ts from the study indicated that there was signi ficant di fference (p>0.05) in the weight gain, percentage weight gain, and other growth per formance parameters among the fish exposed to di fferent dietar y treatments. Growth of Clar ias gar iepinus reduced wi th increasing inclusion of cooked Jatropha curcas.
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    Open Access
    Growth performance of Clarias gariepinus fingerlings fed graded levels of dietary cooked Jatropha curcas seed meal based diet
    (The Egyptian Society of Experimental Biology, 2016) Jimoh, W. A.; Aderolu, A. Z.; Oladele-Bukola, M. O.; Abdulsalami, S. A.; Okemakin, F. Y.
    The effect of dietar y inclusion of Jatropha curcas on the growth per formance of Afr ican Catfish (Clar ias gar iepinus) was evaluated. Juveni les of Clar ias gar iepinus 225 in numbers were accl imatized for a week, weighed and al lotted into five dietar y treatments where soybean meal was replacedby cooked Jatropha curcas seed meal at 0, 25, 50, 75 and 100%. The diets (40% crude protein and 12% crude l ipid) were isoni trogenous and isol ipidic. Each treatment was repl icated three times wi th fi fteen fish per repl icate. Fish were fed 5% body weight on two equal propor tions per day for 56 days. Growth data were col lected on two-week interval basis. Growth per formance was evaluated using weight gain (g) ; speci fic growth rate (%/day) ; feed conversion ratio (FCR) and protein efficiency ratio as indices. The resul ts from the study indicated that there was signi ficant di fference (p>0.05) in the weight gain, percentage weight gain, and other growth per formance parameters among the fish exposed to di fferent dietar y treatments. Growth of Clar ias gar iepinus reduced with increasing inclusion of cooked Jatropha curcas.
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    Open Access
    Growth Performance, Nutrient Utilization, Metabolic and Digestive Enzymes Studies in Mrigal (Cirrhinus mrigala) Juveniles Fed Graded Levels of Carbohydrate
    (Israeli Journal of Aquaculture - Bamidgeh, 2015) Aderolu, A. Z.; Sahu, N. P.
    A 45-day experiment was carried out to evaluate the growth performance, digestive enzyme activity, and gene expression in mrigal fish Cirrhinus mrigala, fed graded levels of carbohydrate. Three isonitrogenous and isolipidic diets containing either 30, 40 or 50% carbohydrate were formulated using purified ingredients. One hundred and eight Cirrhinus mrigala fingerlings (av. wt. 5.83-6.08g) were equally divided into three groups in 9 plastic tanks of 150L capacity each. Each of the three experimental diets was fed to triplicate groups of fish held under natural light cycle of 12h daylight and 12h darkness. % Weight Gain (WGR), specific growth rate (SGR), feed conversion ratio (FCR) and hepato-somatic index (HSI) were evaluated and found to vary significantly (P<0.05) in relation to the level of carbohydrate in the experimental diets. No significant difference (P>0.05) was found in % weight gain, SGR, and FCR, between the 30% and 50% carbohydrate fed groups but HSI increased significantly across the inclusion levels. Amylase enzyme activity was highest in 40% fed group relative to the 30% and 50% groups. Chymotrypsin and trypsin activities were not significantly different between the 40% and 50% carbohydrate fed groups. Various metabolic enzyme activities in the muscle [aspartate aminotransferase (AST), alkaline amino transaminase (ALT) and malate dehydrogenase (DH)] varied significantly (P<0.05) in response to increased levels of carbohydrate. Gene expression among the digestive enzymes reflected both transitional and translation effect; amylase and trypsin exhibited higher expression with the increasing level of carbohydrate of the experimental diets but results were reversed for chymotrypsin expression. In our study, gene expression was initially significantly higher but then decreased. No consistent pattern was found among the different digestive enzymes.
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    Open Access
    Nutrient digestibility and egg production of laying hens fed graded levels of biodegraded palm kernel meal
    (Ghana Journal of Agriculture Science, 2005-05-07) Aderolu, A. Z.; Iyayi, E. A.; Onilude, A. A.
    A 20-week feeding trial involving 72 Isa brown-laying birds, in a completely randomized design, evaluated the nutrient digestibility and egg production of layers fed diets containing biodegraded palm kernel meal (PKM) at dietary levels of 20 per cent undegraded and 20, 30 and 40 per cent biodegraded PKM, respectively. Biodegradation slightly improved proximate and detergent fibre components compared to the undegraded sample. Among the fibre fractions, hemicellulose was most degraded, whereas acid detergent lignin was least. Proximate component digestibility was similar among the diets except at 40 per cent levels. With the detergent fibre component, increasing the level of the biodegraded PKM caused a significant difference (P<0.05) in fibre component digestibility. Increase in the quantity of biodegraded PKM resulted in significant differences in the values determined for feed intake, hen-day production, and average egg weight; but for egg length, yolk index, egg/yolk ratio and egg shell thickness, there was no significant difference. Despite the significantly lower hen-day production of Diet 3, the feed cost per egg produced was similar to the value determined for birds on Diet 1. It could, therefore, be concluded that when prices for soybean meal and maize are high , up to 30 per cent PKM could be used in layers’ diets.