Growth performance
The results pertaining to growth performance in terms of phase wise body weight gain (BWG), feed intake (FI) in terms of (g/b) and feed conversion ratio (FCR) as influenced by dietary inclusion of different levels of rice DDGS with or without enzymes in the diet of broiler chicken are presented in the Table 4.
Body weight gain
During pre-starter phase, BWG was significantly (P<0.01) higher in control as compared to 12.5 and 15% rice DDGS groups. The BWG was significantly (P<0.01) higher in 15% rDDGS group as compared to 12.5% rDDGS group in pre-starter phase. There was no significant (P>0.05) difference in BWG in starter phase between different levels of rice DDGS. However in finisher and overall phases, BWG was significantly (P<0.01) lower in 15% rDDGS group as compared to control and 12.5% rice DDGS group.
During pre-starter phase, BWG was significantly (P<0.05) higher in protease and multienzymes groups as compared to xylanase and without enzyme groups. Body weight gain was significantly (P<0.05) higher in xylanase groups as compared to other groups during starter phase. However in finisher and overall phases, BWG was significantly (P<0.01) higher in all enzymes supplemented groups (X, P and M) as compared to without enzyme groups.
Interaction of rice DDGS and enzymes showed that during prestarter phase, BWG was significantly (P<0.01) higher in T2 as compared to T1, T5, T6, T8, T9, T10 and T11 groups. Body weight gain was significantly (P<0.01) higher in T6 as compared to T1, T2, T5, T8 and T11 groups during starter phase. During finisher phase, BWG was significantly (P<0.01) higher in T4, T7 and T8 as compared to T1, T5, T9, T10, T11 and T12 groups. However in overall phase, BWG was significantly (P<0.01) lower in T1,T5, T9, T11 and T12 groups as compared to other dietary treatments. Thus, interaction of rice DDGS and enzymes showed beneficial effects in protease supplemented group in rice DDGS diets.
Our results are in agreement with
ICAR-CARI Annual Report (2015),
Gupta (2016) and
Rao et al., (2016). Addition of rice DDGS up to 10% level did not exert any adverse effect on BWG of broiler chickens (
ICAR-CARI, 2015).
Gupta (2016) reported up to 10% rice DDGS have shown significantly (P<0.05) higher BWG in layers with protease supplementation.
Rao et al., (2016) reported BWG was not affected by incorporating rice DDGS up to 10%, but depressed significantly at 15% level in broiler.
Feed intake
The results revealed that no significant (P>0.05) difference was observed in feed intake by incorporating different levels of rice DDGS at 0, 12.5 and 15% levels with or without enzymes supplementation (X, P, M) or due to interaction of rice DDGS and enzymes.
Our results are in disagreement with
Gupta (2016) and
Rao et al., (2016). Gupta (2016) reported dietary inclusion of rice DDGS upto 10% showed significantly (P<0.01) higher feed intake in layer chicken.
Rao et al., (2016) reported rice DDGS at 15% level depressed feed intake during in layer.
Feed conversion ratio
The results revealed that during pre-starter phase, FCR was significantly (P<0.05) poor in 15% rice DDGS level as compared to 0 and 12.5% levels. There was no significant (P>0.05) difference in FCR in starter phase between different levels of rice DDGS. However in finisher and overall phases, FCR was significantly (P<0.01) poor in 15% rDDGS level as compared to 0 and 12.5% rDDGS levels.
Effect of with or without enzymes and interaction of rice DDGS and enzymes on phase wise FCR revealed that no significant (P>0.05) difference between different dietary treatments and control. There was no significant (P>0.05) difference in FCR in pre-starter and starter phases with or without enzymes. However in finisher and overall phases, FCR was significantly (P<0.01) better in all enzymes (X, P and M) supplemented groups as compared to without enzyme groups.
Our results are in agreement with
ICAR-CARI Annual Report (2015),
Gupta (2016) and
Rao et al., (2016). Addition of rice DDGS up to 10% level did not exert any adverse effect on FCR of broiler chickens (
ICAR-CARI, 2015).
Gupta (2016) reported protease enzyme supplementation was found significantly (P<0.05) beneficial in terms of FCR in layer up to 10% inclusion level of rice DDGS.
Rao et al., (2016) reported rice DDGS significantly (P<0.05) improved feed efficiency at 5 and 10% levels but at 15% level feed efficiency was depressed significantly compared to control in broiler chickens. In our results, poor growth performance at 15% rice DDGS group may be associated with poor energy and protein digestibility. No other research work is available in the literature regarding augmenting feeding value of rice DDGS through dietary addition of enzymes in broilers.
Nutrient utilization
The results pertaining to nutrient utilization as affected by feeding different levels of rice DDGS with or without enzymes are presented in (Table 5). The results revealed that no significant (P>0.05) difference was found in dry matter and gross energy metabolizability, nitrogen retention, calcium and phosphorous retention (%) of the diet by incorporating different levels of rice DDGS at 0, 12.5 and 15% levels and interaction of rice DDGS with enzymes. Enzymes supplementation on nutrient utilization revealed that no significant (P>0.05) difference was found between treatments in calcium and phosphorous retention (%). The DMM, nitrogen retention and AME of the diets were significantly (P<0.01) increased in enzymes (X, P and M) as compared to without enzyme groups. The GEM was significantly (P<0.01) higher in xylanase enzyme groups as compared to multienzymes and without enzyme groups, but there was no significant (P>0.05) difference between xylanase and protease enzyme groups.
Our results are in agreement with
Gupta (2016).
Gupta (2016) reported that DMM, nitrogen, calcium and phosphorus retention (%) of laying hens did not differ significantly (P>0.05) up to 10% addition of rice DDGS in layer diet. Similarly
Raju et al., (2021) reported that rice DDGS could be fed to chicks up to 10% in the diet without affecting nutrient utilization in terms of DM digestibility and protein retention. No other study is available in the literature regarding nutrient utilization of rice DDGS with enzyme supplementation by poultry birds.
In our results, poor energy, DMM and nitrogen retention of rice DDGS may be associated with level and type of crude fiber present and type of protein quality. The rice DDGS is high gross energy and protein feed but their availability to the body is limited. Better nutrient utilization may be associated with improved energy and protein digestibility by enzyme supplementation. Their supplementation hydrolyses fiber fraction, reduces the digesta viscosity and nutrient encapsulation, thereby increases nutrient utilization in the body.
Cost economics
The results pertaining to cost economics in broiler chicken as affected by feeding different levels of rice DDGS with or without enzymes are presented in Table 5. Feeding different levels of rDDGS (0, 12.5 and 15%) levels revealed that feed cost per kg live weight and meat yield was significantly (P<0.01) lower in 12.5% rDDGS level as compared to 0 and 15% rDDGS levels. Feed cost per kg live weight was significantly (P<0.01) higher in control as compared to 12.5 and 15% rice DDGS level. Enzyme (xylanase, protease and multienzymes) supplementation revealed that feed cost per kg live weight was significantly (P<0.05) lower in all three enzymes (X, P and M) supplemented groups as compared to without enzyme supplementation. However, protease enzyme showed numerically lower feed cost per kg live weight as compared to xylanase and multienzymes supplementation. Interaction of rice DDGS and enzymes did not show any significant (P>0.05) difference in feed cost. Thus, it concluded that 12.5% rice DDGS with protease found to be most cost effective. Live weight and meat yield due to 12.5% rice DDGS reduced feed cost per kg feed consumed by 9.52 and 9.60 respectively. Protease enzyme supplementation in 12.5% rice DDGS further reduced feed cost per kg live weight by 3.03%. Multienzymes supplementation found to be most cost effective in corn-soya diet and it reduced feed cost per kg live weight by 1.84%.
Our results are in agreement with
Gupta (2016) who reported that increasing the level of rice DDGS from 0 to 10% tended to reduce the feed cost significantly (P<0.01) with protease supplementation in layer. No other literature available on the economic aspects of rice DDGS addition. Protease supplemented group showed lower feed cost per kg live weight numerically as compared to xylanase and multienzymes supplemented groups due to relative lower cost of protease enzyme used in this study. There was no significant (P>0.05) difference among protease, xylanase and multienzymes supplemented groups per kg live weight gain. Feed cost per kg live weight was reduced significantly (P<0.05) in all three enzyme supplemented groups (xylanase, protease and multienzymes) due to better growth performance and nutrient utilization in rice DDGS diet.