The present study was conducted on 320, one-day old commercial straight run broiler chicks for a period of six weeks. The birds were randomly divided into eight treatment groups i.e. A, B, C, D, E, F, G and H comprising of 40 birds in each treatment with two replications of 20 birds in each replicate. Treatment group A served as control. Treatment group B was control with β-mannanase enzyme. Guar meal through feed was incorporated @ 5%, 10%, 15% with β-mannanase 5g, 10g and 15g /100 kg of feed to D, F, H Treatment groups. However plain GM was incorporated through feed to treatment groups C, E and G @ 5, 10, and 15 percent respectively. There were significant differences (P<0.05) observed for weekly gain in weight, weekly feed consumption and weekly feed conversion ratio when the diet was supplemented with β-mannanase enzyme up to 5 percent level of incorporation of GM. Body weights at 6thweek were 2031, 2218, 1946, 2112, 1768.50, 1849.50, 1663.50 and 1726g for treatment groups A, B, C, D, E, F, G and H respectively. The cumulative weight gain at 6th week were 1986, 2173.50, 1901, 2067, 1723.50, 1804.50, 1618.50 and 1681 g for treatment groups A, B, C, D, E, F, G and H respectively. The Cumulative feed consumption exhibited significant differences (P<0.05) at 6th week. The feed consumption at the end of 6th week was 3422, 3623.50, 3318.50, 3500, 3278, 3334.50, 3264.50, and 3290 g for treatment groups A, B, C, D, E, F, G and H, respectively. The cumulative feed conversion ratio also revealed significant findings at the end of 6th week. The FCR was 1.72, 1.66, 1.74, 1.69, 1.90, 1.84, 2.01 and 1.95 for the A, B, C, D, E, F, G and H, respectively. The total cost of broiler production was Rs. 131.62, 136.97, 131.76, 137.15, 133.66, 135.65, 133.86 and 135.24 for treatment groups A, B, C, D, E, F, G, and H, respectively. The net profit per bird was highest for Treatment group B (Rs.36.07), followed by D (Rs.27.58), A (Rs.26.79), C (Rs.20.02), F (Rs.8.61), E (4.28), H (-0.61) and G (Rs.-4.11). However profit per bird was more in the control group supplemented with β- mannanase enzyme @ 5 g /100 kg of feed followed by GM supplemented @ 5 % with β- mannanase enzyme @ 5 g /100 kg of feed. The results of the present study clearly inferred that lower level i.e. @5 % replacement of soya Doc with toasted guar meal had exhibited beneficial effects with respect to BWG,FCR and economics of broiler production with supplementation of β- mannanase enzyme. It can be further be concluded that addition of toasted guar meal above 10 and 15% cannot work as a potential tool for partial replacement of soya Doc in poultry diet even after the supplementation of β- mannanase enzyme because of adverse effect of guar meal on broiler performance.
The poultry sector in India has undergone a paradigm shift with annual growth rate of 5.57% and 12.44% in egg and broiler production, respectively. The poultry sector plays vital role in improving the global food security status of the consumers. It has transformed from mere backyard poultry farming into a poultry industry. This transformation has involved sizeable investments in breeding, hatching, rearing, processing of poultry meat & eggs. The poultry farmers in India have moved from rearing non-descript birds to rearing of Ven-cobb, Ross and Hubbard as hybrid broilers strains, which ensure faster growth, good livability, excellent feed conversion and high profits to the poultry farmers. The industry has grown largely due to the initiative of private enterprise, government intervention, considerable Indigenous poultry improved genetics capabilities, and support from the complementary veterinary health, poultry feed, poultry equipment and poultry processing sectors. Commercial and small holder poultry enterprises are growing, thereby increasing demand for poultry feeds. Soybean and fishmeal have traditionally been the main protein sources in poultry feeds, but with the growth of the poultry sector and the World’s population, it is difficult to meet the increasing demand of chicken, egg and meat. Due to shortages and cost consideration, it is inevitable that more consideration is given to alternative protein supplements to be utilized in poultry feeds. Poultry production has been inadequate due to the shortage of and subsequent high price of protein sources. A possible way to reduce poultry feed cost is finding alternative to conventional protein sources which are inexpensive, efficient and locally available. Hence, there exists a need to consider alternative source of protein.
Cluster bean (Cyamopsis tetragonoloba) commonly known as guar is derived from Sanskrit word “GAU AAHAR” meaning cow fodder or otherwise fodder of livestock, is also known by many other names such Khutti, Davari etc. Guar is a drought summer tolerant annual legume currently grown for its high concentration of galactomannan gum which is used as a thickener in food, cosmetics and pharmaceuticals as well as in oil well drilling mud, ore flotation, papermaking, and even explosives. India leads the list of the major guar producing countries of the world contributing to around 80% in world’s total production of around 7.5 lacs to 10 lacs tons, Tyagi et al. (2015).
Guar meal is a relatively inexpensive high protein meal produced as a by-product of guar gum industry. The protein content of guar meal ranges between 36 to 60% depending on fraction type. Guar meal results from combinations of two fractions, the germ and hull containing approximately 60 and 35% protein, respectively (Conner, 2002). The germ and hull compose approximately 44 and 21% of the guar bean, respectively. Guar meal left after removal of gum i.e. the endosperm from both hull and germ of guar seed is potential alternative protein feed. Chemical composition of toasted guar meal was reported as 50.27% protein, 5.32% ether extract, 6.24% crude fibre, 7.08% total ash, 1.28% acid insoluble ash, 31.09%. The crude protein contents of germ, hull and endosperm (gum) are 45, 35, 5-6 %, respectively, Tyagi et al. (2015) these fractions contain residual gum in different concentrations. Guar gum is a highly viscous galactomannan polysaccharide. Guar gum is composed of 65% mannose and 35% galactose, Dinani et al. (2017)
Inspite of rich nutritive value of guar meal, its use may limit due to presence of antinutritional factors such as trypsin inhibitor and β-mannas. The trypsin inhibitor acts on the trypsin and chymo trypsin in the digestive tract thereby interfering the feed utilization. The effect of these antinutritional factors may be reduced by toasting of feed material. Whereas, β-mannas a linear polysaccharides significantly reduces growth and increases feed: gain ratio in broilers (Daskiran et al., 2004), β-mannanase enzyme is found effective in degrading β-mannas of feed thereby improving metabolizable energy, growth and feed conversion in broilers (McNaughton et al., 1998).
Materials and Methods
The present study was carried out on 320, healthy day old ven-cobb straight run broiler chicks for a period of 42 days (6 weeks) from 22nd March to 2nd May 2017 in the Department of Poultry Science, College of Veterinary and Animal Sciences, MAFSU, Parbhani. The broiler birds obtained from M/s. Venkateswara Hatcheries Pvt. Ltd. Pune, Dist. Pune, Maharashtra. On arrival, the chicks were weighed and distributed randomly into eight treatment groups viz, A, B, C, D, E, F, G and H with two replicates of 20 chicks in each. The brooding was carried out with electric hover brooders as source of heat and light. Brooding was continued until 2 weeks of age in the respective pen of each replication and treatment group. Toasted guar meal was purchased from local market and the β– mannanase enzyme was procured from Advanced Bio-Agrotech Limited, Pune, India having concentration of 1,05,187IU/g. The toasted guar meal was added in the feed at three different dose levels viz, 5%, 10%, and 15%. However the enzyme β– mannanase was incorporated @ 5g, 10g and 15g per quintal of feed respectively. The feed was prepared as per BIS (2007), at the feed mixing plant, Department of Poultry Science, College of Veterinary and Animal sciences, MAFSU, Parbhani. The experimental design used in the present study for housing the broilers is presented in Table 1.
Table 1: Experimental design used for housing of broilers in the present study
|Treatment Group||Treatment Group Details||No. of Birds/Replication||No. of Replicates||Total No. of Birds|
|A||Standard broiler diet||20||2||40|
|B||Standard broiler diet with 5g β –mannanase||20||2||40|
|C||Standard broiler diet with toasted guar meal @ 5% replacing soya DOC||20||2||40|
|D||Standard broiler diet with toasted guar meal @ 5% replacing soya DOC with 5g β- mannanase||20||2||40|
|E||Standard broiler diet with toasted guar meal @ 10% replacing soya DOC||20||2||40|
|F||Standard broiler diet with toasted guar meal @ 10% replacing soya DOC with 10g β- mannanase||20||2||40|
|G||Standard broiler diet with toasted guar meal @ 15% replacing soya DOC||20||2||40|
|H||Standard broiler diet with toasted guar meal @ 15% replacing soya DOC with 15g β- mannanase||20||2||40|
The ingredients, nutrient composition of diets had been given in Table 2. The differences among treatment groups were determined by analyzing the data generated, by using Randomized Block Design (Snedecor and Cochran, 1988). The treatment means were compared by least square means and Analysis of Variance. The replicate means were used for all the parameters to generate the data for statistical analysis. The mortality data was subjected to express the percent mortality per treatment group. The simple statistical methods were used for calculating the cost of production and economics of broiler production.
Results and Discussions
The data for means for the weekly cumulative weight gain of broiler chickens at different age groups are presented in Table 3.The mean weekly cumulative weight gains at 1st week of age were 105.00, 109.00, 104.00, 107.00, 102.00, 103.00, 100.00 and 101.50 g for treatment groups A, B, C, D, E, F, G and H, respectively. The mean weekly cumulative weight gain at 2nd week of age for treatment groups A, B, C, D, E, F, G and H were 373.50, 381.00, 369.00, 377.00, 337.00, 347.00, 330.00 and 334.00 g, respectively. The highest weekly cumulative weight gain at 3rd week of age was observed for treatment group B (716.50 g) followed by treatment group D (709.00 g), treatment group A (699.50 g), treatment group C (692.50 g), treatment group F (652.50 g), treatment group E (632.50 g), treatment group H (627.00) and treatment group G (620.50).
|Feed Ingredients||Pre-Starter ration||Starter ration||Finisher ration|
|Control||5% GM||10%GM||15% GM||Control||5% GM||10%GM||15% GM||Control||5% GM|
|Deoiled Soya-bean meal||34||29||24||19||32||25||20||24||17||12|
|Toasted guar meal||0||5||10||15||0||5||10||0||5||10|
|Maize glutein meal||0||1||1.1||2.5||0||2||2.5||3.5||5.5||6|
Table 2: Percent ingredient and nutrient composition of broiler rations used in experiment
Table 3: Cumulative weight gain (g) of broilers supplemented with toasted guar meal and β- mannanase enzyme for 1-6 week period
Means with different superscript within the column differ significantly
The mean weekly cumulative weight gain at 4th week of age for treatment groups A, B, C, D, E, F, G and H were 1141.00, 1193.50, 1107.50, 1167.50, 998.50, 1055.50, 923.50 and 967.00 g, respectively. The mean weekly cumulative weight gain for treatment groups A, B, C, D, E, F, G and H at 5th week of age were 1560.00, 1683.00, 1494.00, 1611.50, 1349.50, 1422.50, 1251.00 and 1307.00 g, respectively. The mean weekly cumulative weight gain at 6th week of age for treatment groups A, B, C, D, E, F, G and H were 1986.00, 2173.50, 1901.00, 2067.00, 1723.50, 1804.50, 1618.50 and 1681.00 g, respectively.
The statistical analysis of variance of data revealed significant (P<0.01) influence on weekly live body weight of birds Table 4.
Table 4: ANOVA for weekly body weights (g) of broilers supplemented with toasted guar meal and β- mannanase enzyme for 1-6 week period
The birds from the treatment group B receiving control diet with β-mannanase recorded highest body weight among the various treatment groups. However, the birds from treatment group H receiving a diet with replacement of soya Doc by toasted guar meal with supplementation of β-mannanase @ 15gm/ 100kg of feed recorded significantly low body weight followed by treatment group G, treatment group E, treatment group F, treatment group C, A and D. Significant improvement in body weight was achieved by supplementation of β-mannanase 5gm/100kg feed over rest of the treatment groups. Similar trend of significant increase in body weight was observed for treatment group D receiving the diet with toasted guar meal @5%replacement of soya Doc and supplementation of β-mannanase @ 5gm/100kg of feed. Rest of the treatment groups had weekly body weight lower as compared to the control group (A).
Similar findings with respect to body weight gain were reported with the soya Doc with toasted guar meal @ 5% and with supplementation of β-mannanase @ 5gm/100 kg of feed. This clearly indicates that the growth depression properties of toasted guar meal may be ameliorated by treating the diet with β-mannanase enzyme capable of hydrolyzing the β -mannanans. It has been found that supplementation of β-mannanase enzyme to toasted guar meal based diet up to 5% replacement to soya Doc helps in overcoming the growth depressing properties of toasted guar meal. However beyond 5% replacement of soya Doc with toasted guar meal had deleterious effects on body weight. These negative impacts on body weight may be related to intestinal viscosity, diarrhea, and increased intestinal viscosity and decreased digestive enzyme activity throughout the small intestine.
The results in the present study are in agreement with the Dinani et al. (2010) who revealed that 15% toasted guar meal with enzyme supplementation improved the overall growth performance of broilers. Similarly Gharaei et al. (2012) observed that guar meal can be safely use up to 6% in broilers and with supplementation of β-mannanase showing further improvement in performance of broiler chicks. Rama Rao et al. (2014) revealed that supplementation of xylanase, glucanase, mannanase improved the performance of Vanraja chicken compared to those fed guar meal @ 200 mg/kg feed without enzyme. Similar to the present study, Imran et al. (2014) observed improved growth rate by supplementation of β-mannanase. Similar findings were reported by Nasrala (2015), Ahmad and Abou-Elkhair(2016) and Khaleed et al. (2017). The supplement of NSP enzymes was found to be beneficial in guar meal based diets for improvement in body weights in broilers as revealed by Nikam et al. (2017). In contrast to the present findings Kamran et al. (2002), Lee et al. (2003b), Bhutia (2006),Tyagi et al. (2011), Mohayaye and Kamiri (2012) revealed no significant effects in body weight gain of broilers with β-mannanase supplementation in guar meal based diets.
The data for means for the cumulative feed consumption of the broiler at different age groups are presented in Table 5.
Table 5: Weekly cumulative feed consumption (g) of broilers supplemented with toasted guar meal and β- mannanase enzyme for 1-6 weeks period
*Means of different superscript differ significantly each other
The mean cumulative feed consumption at 1st week of age were 135.50, 139.00, 134.50, 137.50, 133.00, 133.50, 134.00 and 132.50 g for treatment groups A, B, C, D, E, F, G and H respectively. The mean cumulative feed consumption at 2nd week of age for treatment groups A, B, C, D, E, F, G and H were 482.50, 489.00, 478.50, 485.00, 472.00, 475.50, 472.00 and 472.50 g, respectively. The mean cumulative feed consumption at 3rd week of age for treatment groups A, B, C, D, E, F, G and H were 956.50, 969.00, 949.00, 960.50, 942.00, 944.00, 941.00 and 944.00 g, respectively. The mean cumulative feed consumption at 4th week of age for treatment groups A, B, C, D, E, F, G and H were 1669.00, 1729.00, 1622.00, 1695.50, 1591.00, 1634.50, 1595.00 and 1605.00 g, respectively. The mean cumulative feed consumption at 5th week of age for treatment groups A, B, C, D, E, F, G and H were 2553.00, 2712.00, 2442.00, 2607.00, 2432.00, 2485.50, 2418.50 and 2439.00 g, respectively. The mean cumulative feed consumption at 6th week of age were 3422.00, 3623.50, 3318.50, 3500.00,3278.00, 3334.50, 3264.50 and 3290 g for treatment groups A, B, C, D, E, F, G and H, respectively. The overall mean weekly feed consumption for birds were 1536.41, 1610.25, 1490.83, 1564.16, 1474.66, 1501.25, 1470.83, and 1480.50 g for treatment groups A, B, C, D, E, F, G and H, respectively.
The analysis of variance for overall cumulative feed consumption revealed significant (P<0.01) difference among various treatment groups Table 6.
Table 6: ANOVA for weekly cumulative feed consumption (g) of broilers supplemented with toasted guar meal and β- mannanase enzyme for 1-6 week period
Significantly higher cumulative feed consumption (P<0.01) was observed for treatment group B followed by treatment group D which clearly indicated that β-mannanase is responsible for hydrolyzing the trypsin inhibitors as well as the mannas fraction from the soybean meal and toasted guar meal respectively thereby reducing the intestinal viscosity and maximizing utilization of the feed nutrients by broilers. On other hand significantly lower cumulative feed consumption was observed for birds feed on toasted guar meal supplemented at 10 and 15 % level with or without β-mannanase. These results inferred that the supplementation of guar meal at higher percentage above 10 and 15 % levels reported to exhibit detrimental effects on growth performance of broilers, this may be due to increased intestinal viscosity due to some indigestible polysaccharides like residual guar gum, trypsin inhibitors and haemagglutinins present in TGM which are responsible for increased intestinal viscosity and decreased the feed intake. These results are in accordance with Lee et al. (2005), Dinani et al. (2010), Turki et al. (2011), Tyagi et al. (2011), Gharaei et al. (2012), Nasrala et al. (2015) and Ahemad and Abu-Elkhair (2016).
However, the studies reported by Bhutia (2006) are in contrast with present findings who reported that addition of feed grade commercial enzyme mix to broiler quail diet did not improved the overall feed intake. The data for the cumulative feed conversion ratio of broilers with supplementation of guar meal and β-mannanase through feed for 1-6 weeks duration through feed for 1-6 weeks period is present in Table 7 and also depicted.
The mean cumulative feed conversion ratios at 1st week of age were 1.29, 1.27, 1.29, 1.28, 1.30, 1.29, 1.34 and 1.30 for treatment groups A, B, C, D, E, F, G and H, respectively. The mean cumulative feed conversion ratios at 2nd week of age for treatment groups A, B, C, D, E, F, G and H were 1.29, 1.28, 1.29, 1.28, 1.40, 1.37,1.43 and 1.41, respectively. The mean cumulative feed conversion ratios at 3rd week of age for treatment groups A, B, C, D, E, F, G and H were 1.36, 1.35, 1.37, 1.35, 1.48, 1.44, 151 and 1.50, respectively. The mean cumulative feed conversion ratios for treatment groups A, B, C, D, E, F, G and H at 4th week of age were 1.46, 1.44, 1.46, 1.45, 1.59, 1.54, 1.72 and 1.66, respectively. The mean cumulative feed conversion ratios for treatment groups A, B, C, D, E, F, G and H at 5th week of age were 1.63, 1.61, 1.63, 1.61, 1.80, 1.74, 1.93 and 1.86, respectively. The mean cumulative feed conversion ratio for treatment groups A, B, C, D, E, F, G and H at 6th week of age were 1.72, 1.66, 1.74, 1.69, 1.90, 1.84, 2.01 and 1.95. The overall mean cumulative feed conversion ratios of birds at the end of experiment were 1.46, 1.44, 1.46, 1.44, 1.58, 1.54, 1.66 and 1.61 for treatment groups A to H, respectively.
Table 7: Cumulative feed conversion ratio of broilers at different age groups supplemented with toasted guar meal and β-mannanase
*Means of different superscript differ significantly each other
The statically analysis of variance of Table 8 for weekly cumulative FCR of broiler supplementation with toasted guar meal and β-mannanase rebuild highly significant influences (P<0.01).The superior cumulative feed conversion ratio was observed for treatment group D, treatment group B, treatment group C, treatment group A and inferior cumulative FCR was recorded for treatment group G, treatment group H and treatment E receiving more than 5% toasted guar meal with or without β-mannanase.
Table 8: ANOVA for weekly cumulative feed conversion ratio of broilers at different age groups supplemented with toasted guar meal and β-mannanase
A critical observation of data at 6th week for cumulative FCR revealed that up 5% addition of TGM with or without β- mannanase exhibited improvement in FCR. However, increased levels of TGM above 5% with or without β-mannanase enzyme showed deleterious effect on feed conversion ratio. The reasons for poor FCR may be increased in intestinal viscosity, reduced nutrient absorption from the intestinal villi because of binding effect of the complex and indigestible polysaccharides, such as guar gum. The present findings are in accordance with Kamran et al. (2002), Lee et al. (2003a), Larhang and Torki (2011), Turki et al., (2011),Gharaei et al. (2012), Rama Rao et al. (2014), Nasrala et al. (2015), Ahmed and AbuElhair.(2016), Khaled et al. (2017) also reported improved FCR in guar meal based diets supplementation with β-mannanase enzyme.
However, the present findings are contradictory with Grover et al. (2001), Bhutia (2006), Dinani et al.( 2010), Tyagi et al. (2011) and Ramteke et al. (2014) who reported that addition of enzyme did not improved the FCR in broilers. The economics of broiler production was carried out for different treatment groups and is presented in Table 9.
Table 9: Economics of broiler production supplemented with toasted guar meal and β-mannanase enzyme
|1||Chick cost (Rs)||38||38||38||38||38||38||38||38|
|3||Feed cost Rs./kg|
|4||Feed cost Rs./bird|
|5||Misc. cost (Rs)/bird||8||8||8||8||8||8||8||8|
|6||Production cost Rs.||131.62||136.97||131.76||137.15||133.66||135.65||133.86||135.24|
|7||Av. Live wt. (g)||2031||2218.5||1946||2112||1768.5||1849.5||1663.5||1726|
|8||Sale receipt @ Rs. 78/kg live wt||158.41||173.04||151.78||164.73||137.94||144.26||129.75||134.62|
|9||Net profit/ bird||26.79||36.07||20.02||27.58||4.28||8.61||-4.11||-0.61|
|10||Net profit Rs. /kg||13.19||16.25||10.28||13.05||2.42||4.65||-2.47||-0.35|
The economics of broiler production of the experiment was worked out by considering the purchase rates of chicks ingredients, miscellaneous expenditure and the prices at which the birds were sold in the market on live weight basis. The cost of day old chicks, feed, medication, vaccination, litter and other overheads were considered while calculating the cost of production. However, the costs of labour were not considered in calculating the cost of production of the broilers as this experiment being a postgraduate research work. The cost of pre-starter, starter and finisher ration for all control and treatment groups are presented in Table 9.
The prices of pre-starter, starter and finisher ration of treatment groups A, B, C, D, E, F, G and H were variable because of supplementation of toasted guar meal with β- mannanase enzyme. The total cost of feeding of birds recorded as Rs. 85.62, 90.97, 85.76, 91.15, 87.66, 89.65, 87.86 and 89.24 for treatment groups A, B, C, D, E, F, G and H, respectively. The total feeding cost for treatment group A was lower followed by treatment group C, E, G, H, F, B and D. The cost of broiler production were Rs. 131.62, 136.97, 131.76, 137.15, 133.66, 135.65, 133.86 and 135.24 per bird for treatment groups A, B, C, D, E, F, G and H, respectively. The total cost of broiler production for treatment group A was lower followed by treatment groups C, E, G, H, F, B and D. The total sale price fetched from the bird sold on live weight basis for treatment group B (Rs.173.04) was highest followed by D (Rs.164.73), A (Rs.158.41), C (Rs151.78.),F(Rs.144.26),E (Rs.137.94) H (Rs.134.62) and G (Rs.129.75).The net profit per bird was higher as Rs.36.07 for treatment group B, followed by Rs.27.58,26.79,20.02,8.61,04.28,-,0.61and-4.11for treatment groups D,A,C,F,E,H ,and G, respectively. The net profit per kg on live weight basis for treatment group B was higher as Rs. (16.25) followed by A (Rs.13.19), D (13.05), C (10.28) F, (4.65) E, (2.42), H (-0.35) and G (-2.47)
The results of economic evaluation clearly indicated that the diet with toasted guar meal up to 5% and supplementation of β- mannanase resulted in highest net profit per bird compared to treatment group A (control) and rest of the treatment groups, except treatment group B. The highest profitability in treatment group B receiving a basal diet with β- mannanase was the influence of β- mannanase enzyme on performance of bird due to come bioavailability. The replacement of 5% soya Doc by toasted guar meal improved net profitability per bird by 2% when compared to control diet. However, other treatment group containing 10 and 15% toasted guar meal decease the relative profitability compared to control groups. This might be due to the lowest productive performance (body weight, feed conversion ratio, and higher mortality).The findings in the present study are in agreement with Kamran et al. (2002) revealed that the level of guar meal more than 5% in broiler ration decrease the feed cost but at the same time cost per kg live weight gain Increase compare to control. Similarly Salma et al. (2015) reported that inclusion of guar korma meal to the broiler diet as a partial replacement of soya meal improved the relative economic efficiency of diet compare to control diet. However, Bhutia (2006) reported that no effect of cost of production per kg live weight was observed, Tyagi et al. (2011) calculated the feed cost per kg live weight gain did not differ statically among control and guar meal fed groups in broilers.
It can be concluded from the present study that the performance of the broilers reared with toasted guar meal based diets was improved in terms of BWG, FI, FCR and economics with the supplementation β- mannanase enzyme @ 5 g /100 kg of feed in standard control diet followed by GM supplemented @ 5 % with β- mannanase enzyme @ 5 g /100 kg of feed. The results of the present study inferred that higher levels of GM (10 and 15 %) replacing the soya Doc had exhibited adverse effect on broiler performance and profitability. It can further be concluded that addition of toasted guar meal in poultry diet above 10 and 15% level cannot work as a potential tool for partial replacement of soya even after the supplementation of β- mannanase enzyme.