IN SACCO DEGRADABILITY OF WHEAT STRAW TREATED WITH UREA AND FIBROLYTIC ENZYMES

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1 Indian J. Anim. Res., 48 (1) : 21-26, 2014 DOI /j AGRICULTURAL RESEARCH COMMUNICATION CENTRE IN SACCO DEGRADABILITY OF WHEAT STRAW TREATED WITH UREA AND FIBROLYTIC ENZYMES Sayar Ahmad Mir* 1, M.S. Pannu, Ovais Aarif 2 and Nazam Khan 3 Department of Animal Nutrition, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana , India Received: Accepted: ABSTRACT The present investigation was undertaken to study the effect of different levels of exogenous fibrolytic enzymes applied on untreated and urea fermented wheat straw on the digestion kinetics of DM and NDF. The untreated wheat straw and the enzyme treated wheat straw had comparable chemical composition while urea treated wheat straw with urea (3.5:96.5) resulted in higher total ash associated with simultaneous decline in organic matter content, The proportion of rapidly soluble fraction, degradation rate and effective degradation for DM and NDF was highest in case of urea fermented wheat straw treated with 0.2% enzyme level but the effect was not significant from the fermented wheat straw treated with 0.2% enzyme level.the insoluble but degradable fraction for both DM and NDF also varied in different enzyme level treatments but its value was highest in case of untreated wheat straw as compared to enzyme and urea treated wheat straw. Key words: Digestion kinetics, Fibrolytic enzyme, Wheat straw. INTRODUCTION Increasing the nutrient availability for better utilization of crop residues has been a primary focus of research in dairy cattle nutrition. Over the years, significant improvement in forage cell wall digestibility has been achieved through forage breeding programs and agronomic advances. Despite these improvements, forage digestibility continues to limit the utilization of available energy by ruminants and correspondingly, contributes to excessive nutrient excretion by livestock. It is a well known fact that lignin acts as a physical barrier and impedes microbial breakdown of these materials. There are various methods of increasing forage utilization and increasing the productive efficiency in ruminants. One such method is the use of exogenous fibrolytic enzymes which hold promise as a means of increasing forage utilization and improving the productive efficiency of ruminants. The objective of this study was to check nutritional evaluation of untreated wheat straw, urea treated wheat straw, fibrolytic enzyme treated wheat straw, urea and fibrolytic enzymes treated wheat straw on degradability of fibrous feed material. MATERIALS AND METHODS The experiment was performed in the department of Animal Nutrition, GADVASU, Ludhiana. Three healthy adult rumen fistulated male buffaloes weighing kg were used in this study. Proper care was taken to avoid infection at fistula site throughout the experimental period. The ration of these animals was roughage based. The nutrient requirements were met through seasonal greens and concentrate mixture as per Kearl (1982). Digestion kinetic studies were started after three weeks of adaptation period The wheat straw used for studying the digestion kinetic parameters of dry matter and neutral detergent fiber in in sacco experiment was treated with enzymes just before putting samples in the nylon bags. The level of the enzyme product (FIBERZYME) provided by Zeus Biotech Ltd. containing main fibrolytic enzymes viz Cellulase, Xylanase, Glucanase, Mannanase, Pectinase, & galactosidase and Lignase used in * Corresponding author s mirsayarvet@gmail.com 1-3 National Dairy Research Institute, Karnal (India)

2 22 INDIAN JOURNAL OF ANIMAL RESEARCH this experiment was 0.1, 0.2 and 0.3 kg per tonne of feed. Degradability of DM and NDF was assessed by incubating the sample in triplicate in the rumen of three fistulated buffaloes for 0, 3, 6, 9, 12,18, 24, 36, 48, 60,72, 84 and 96 hours by nylon bag technique. Different digestion kinetic parameters of dry matter and cell wall were calculated according to Orskov and Mc Donald (1979). The calculations for potential and effective degradabilities of neutral detergent fibre (NDF) were based as per the method described by McDonald (1981). Preparation of fermented wheat straw (FWS): In one batch four quintals of wheat straw was spread on floor and sprayed with solution of 14 Kg urea dissolved in 200 litres of water. The straw was mixed thoroughly and stacked by manual pressing. After 10 days, the stack was dismantled from one side and the fermented straw was fed to the experimental animals. Digestion kinetic parameters: Different digestion kinetic parameters of dry matter and cell wall were calculated according to Orskov and Mc Donald (1979). The calculations for potential and effective degradabilities of neutral detergent fibre (NDF) was done as per the method described by McDonald (1981). Statistical analysis: The Data was analysed by using one way analysis of variance (Snedecor and Cochran 1989) for statistical differences in the treatment means. The overall means for all the parameters were compared using Duncan s multiple range test. (Duncan 1995). RESULTS AND DISCUSSION Digestion kinetic characteristics of enzyme treated wheat straw: The values for the rapidly soluble fraction (a) in case of DM of wheat straw treated with different enzyme levels are comparable in untreated wheat straw and 0.1% enzyme treated wheat straw and are statistically non significant. The values for a in 0.2% and 0.3% enzyme treated wheat straw were comparable and were statistically non significant. However the first two groups i.e untreated wheat straw and 0.1% enzyme treated wheat straw were significantly lower from the last two i.e. 0.2% and 0.3% enzyme treated wheat straw. The highest value is observed in 0.3% enzyme level as shown in Table 1 and lowest in untreated wheat straw. The higher value at 0.3% enzyme level could be because of faster leaching of soluble cell contents. Pinos-Rodrýguez et al (2008) also found that exogenous fibrolytic enzymes increased the soluble fraction of DM (P< 0.01). fraction (b) also varied in different enzyme level treatments and its value is highest in case of untreated wheat straw as compared to enzyme treated wheat straw. The value decreased from ± in untreated wheat straw to 58.7 ± 0.44 in 0.3% enzyme treated wheat straw. The 0.2% enzyme treated wheat straw is comparable with 0.1% and 0.3% in b but statistically significant from untreated wheat straw. Dean et al (2007) reported similar findings. Degradation rate (c) ranged from to The highest value is observed in 0.3% enzyme level and is comparable with 0.2% enzyme treated wheat straw but statistically significant from untreated and 0.1% enzyme treated wheat straw. However, the lowest value was observed in untreated wheat straw. The average value for rate or degradation was 0.035, 0.04, and in untreated, 0.1%, 0.2% and 0.3% enzyme treated groups respectively. This may be due to synergistic activities of exogenous fibrolytic enzymes (EFE) and endogenous microbial enzymes. The effective degradation at an assumed out flow rate of passage 0.05 h -1 is highest in 0.3% enzyme level and lowest in untreated wheat straw. The 0.2% enzyme level is comparable with 0.1% and 0.3% but statistically higher (p< 0.05).from untreated wheat straw. It is evident that effective degradation values of all the treatments were lower than the true digestible values, indicating that a part of potentially digestible fraction was being prematurely passed out of the rumen along with other digesta. The true digestibility in animals fed 0.1% and 0.2% enzyme treated wheat straw is comparable and is statistically significant from animals fed untreated and 0.3% enzyme treated wheat straw. However, it is highest in animals fed 0.3% enzyme treated wheat straw. In the present study the rumen fil l% were highest in group fed untreated wheat straw and lowest in group fed 0.3% enzyme treated wheat straw and is statistically significant (p< 0.05).. The reason of higher value in untreated wheat straw could be slow fermentation rate that led to higher degree of rumen fill and thus limits the DM intake. Higher rumen fill values are indicative of highest load in rumen and

3 Vol. 48, No. 1, TABLE 1: Digestion kinetic parameters of DM of untreated wheat straw treated with different enzyme levels. Parameters Untreated 0.1% Enzyme 0.2% Enzyme 0.3% Enzyme a, % 7.99 a ± a ± b ± b ± 0.23 b, % c ± bc ± ab ± a ± 0.44 UDF, % c ± b ± ab ± a ± 0.55 ED, % 42.1 a ± b ± bc ± c ± 0.58 TD, % a ± b ± b ± c ± 0.57 RF,% b ± b ± a ± a ± 0.12 c, h a ± b ± c ± c ± are negatively correlated with voluntary intake. Undegradable fraction is highest in group fed untreated wheat straw and lowest in group fed 0.3% treated wheat straw. The animals fed 0.2% enzyme treated wheat straw is comparable with animals fed 0.1% and 0.3% treated wheat straw. The lower value in group fed 0.3% treated wheat straw was because of higher degradation of structural polysaccharides in the rumen and eventually the higher values of (a+ b). Digestion kinetic characteristics of fermented wheat straw treated with different enzyme levels The values for the rapidly soluble fraction (a) in the fermented wheat straw treated with different enzyme levels are comparable in urea treated wheat straw and 0.1% enzyme treated wheat straw and are statistically non significant. The values for a in 0.2% and 0.3% enzyme treated wheat straw are comparable and are statistically non significant. However the first two groups i.e fermented wheat straw and 0.1% enzyme treated fermented wheat straw are statistically significant from the last two i.e. 0.2% and 0.3% enzyme treated fermented wheat straw. The highest (29.54± 0.18) value is observed in 0.3 % enzyme level and lowest (23.96± 1.82) in fermented wheat straw (Table 2). The higher value in 0.3% enzyme level is because of faster leaching of soluble cell contents. fraction (b) also varied in different enzyme level treatments and its value is highest in case of fermented wheat straw as compared to enzyme treated fermented wheat straw. The b in 0.2% enzyme treated fermented wheat straw is comparable with 0.3% enzyme treated fermented wheat straw but statistically significant from untreated and 0.1% enzyme treated fermented wheat straw. This is because of leaching of soluble cell contents by the enzyme action. These findings are consistent with that of Dean et al (2007) Degradation rate represented as c varied from 0.04 to The highest value is observed in 0.3% enzyme level and lowest in fermented wheat straw. These findings are consistent with that of Wang et al (2001). The value of c in animals fed 0.1% enzyme treated fermented wheat straw were comparable with animals fed fermented and 0.2% enzyme treated fermented wheat straw but statistically significant from animals fed 0.3% enzyme treated fermented wheat straw. However, the lowest value was observed in fermented wheat straw. The average value for rate or degradation was 0.04, 0.042, and in TABLE 2: Digestion kinetic parameters of DM of fermented wheat straw treated with different enzyme levels. Para meters Fermented Wheat straw 0.1% Enzyme 0.2% Enzyme 0.3% Enzyme a, % a ± a ± b ± b ± 0.18 b, % 56.96± 0.14 c 55.84± 0.06 b 54.86± 0.24 a 54.78± 0.43 a UDF, % b ± b ± a ± a ± 0.24 ED, % a ± b ± c ± c ± 0.27 TD, % 61.06± ± ± ± 0.37 RF,% b ± a ± a ± a ± 0.12 c, h a ± ab ± b ± c ± 0.001

4 24 INDIAN JOURNAL OF ANIMAL RESEARCH fermented, 0.1%, 0.2% and 0.3% enzyme treated fermented wheat straw groups respectively. This may be due to synergistic activities of EFE and endogenous microbial enzymes. The effective degradation at an assumed out flow rate of passage 0.05 h -1 is highest in 0.3% enzyme level and is comparable with animals fed 0.2% enzyme treated fermented wheat straw. The lowest value of Ed is found in animals fed fermented wheat straw. It is evident that effective degradation values of all the treatments were lower than the true digestible values, indicating that a part of potentially digestible fraction was being prematurely passed out of the rumen along with other digesta. The true digestibility in all the groups of animals is comparable and is statistically non significant. However the lowest value is observed in animals fed urea treated wheat straw and highest value was observed in animals fed 0.3% enzyme treated fermented wheat straw. In the present study the rumen fill values were highest in group fed fermented wheat straw and lowest in group fed 0.3% enzyme treated fermented wheat straw and is statistically significant. The rumen fill in animals fed 0.1, 0.2 and 0.3% enzyme treated wheat straw is comparable and statistically non significant but statistically significant from the animals fed fermented wheat straw. The reason could be slow fermentation rate that led to higher degree of rumen fill and thus limits the DM intake. Higher rumen fill values are indicative of highest load in rumen and are negatively correlated with voluntary intake. Undegradable fraction is highest in group fed fermented wheat straw and lowest in group fed with 0.3% enzyme treated fermented wheat straw (Table 2). The undegradable fraction in animals fed fermented wheat straw and 0.1% enzyme treated fermented wheat straw were comparable. Values are also comparable in animals fed 0.2% and 0.3% enzyme treated fermented wheat straw. The lower value in group fed 0.3% treated fermented wheat straw could be because of higher degradation of structural polysaccharides in the rumen. Digestion kinetic characteristics of NDF of enzyme treated wheat straw: The values for the rapidly soluble fraction (a) in wheat straw treated with 0.2% and 0.3% levels are comparable and are statistically non significant. The values for a in 0.1% enzyme treated wheat straw is comparable with untreated wheat straw and is statistically non significant. The highest value is observed in 0.3%enzyme level and lowest in untreated wheat straw.the higher value in 0.3 % enzyme level could be because of faster leaching of soluble cell contents. fraction (b) also varied in different enzyme level treatments but its value is highest in case of untreated wheat straw as compared to enzyme treated wheat straw. The 0.2% enzyme treated wheat straw is comparable with 0.3% enzyme treated wheat straw but statistically significant from untreated wheat straw as shown in Table 3. Hence our findings are consistent with that of Dean et al (2007). Degradation rate (c) for NDF varied among different enzyme level treatments. It changed from in untreated group to 0.047in 0.3% enzyme treated group. The highest value is observed in 0.3% enzyme level and statistically significant from other groups. However, the lowest value was observed in untreated wheat straw. The average value for rate of degradation was 0.035, 0.04, and in untreated, 0.1%, 0.2% and 0.3% enzyme treated groups respectively. This may be due to synergistic activities of exogenous fibrolytic enzymes (EFE) and endogenous microbial enzymes. The effective TABLE 3: Digestion kinetic parameters of NDF of untreated wheat straw treated with different enzyme levels. Parameters Untreated 0.1% Enzyme 0.2% Enzyme 0.3% Enzyme a, % 7.42 a ± a ± b ± b ± 0.41 b, % b ± ab ± a ± a ± 0.68 UDF, % b ± b ± a ± a ± 0.77 ED, % ± ± ± ±.052 TD, % ab ± ab ± ab ± b ± 0.63 RF,% c ± ab ± a ± a ± 0.20 c, h a ± ab ± bc ± c ± 0.001

5 degradation at an assumed out flow rate of passage 0.05 h -1 is highest in 0.3% enzyme level but statistically non significant from other groups. It is evident from the Table 3 that effective degradation values of all the treatments were lower than the true digestible values, indicating that a part of potentially digestible fraction was being prematurely passed out of the rumen along with other digesta. The true digestibility is highest in animals fed 0.3% enzyme treated wheat straw and statistically significant from other groups. In the present study the rumen fill values were highest in group fed untreated wheat straw and lowest in group fed 0.3% enzyme treated wheat straw and is statistically significant.the reason could be slow fermentation rate that led to higher degree of rumen fill and thus limits the DM intake. Higher rumen fill values were indicative of highest load in rumen and were negatively correlated with voluntary intake. Undegradable fraction is highest in group fed untreated wheat straw and lowest in group fed 0.3% enzyme treated whi ch i s statistically comparable with animals fed 0.2% enzyme treated wheat straw (Table 3). The lower value in group fed 0.3% treated wheat straw was because of higher value of c. D igestion kinetic characteristics N D F of fermented wheat straw treated with different enzyme levels: The values for the rapidly soluble fraction (a) in wheat straw treated with 0.2% and 0.3% levels are comparable and are statistically non significant. The values for a in 0.1% treated wheat straw is comparable with fermented wheat straw and is statistically non significant. The highest value (28.13± 0.40) is observed in 0.3 % level and lowest (22.22± 1.02) in untreated wheat straw (Table 4). The higher value in 0.3% enzyme level could be because of faster leaching of soluble cell contents. Vol. 48, No. 1, These observations are in consistent with Pinos Rodr yguez et al (2008). fraction (b) in Table 4 also varied in different enzyme level treatments but its value is highest in case of fermented wheat straw as compared to enzyme treated wheat straw. The 0.2% enzyme treated wheat straw is comparable and statistically non significant with 0.3% enzyme treated wheat straw. Degradation rate (c) for NDF varied from to The highest value is observed in 0.3% enzyme level and statistically non significant from animals fed 0.2% enzyme treated fermented wheat straw. However, the lowest value was observed in fermented wheat straw. The average value for rate or degradation was 0.04, 0.048, and in untreated, 0.1%, 0.2% and 0.3% enzyme treated groups respectively. This may be due to synergistic activities of EFE and endogenous microbial enzymes.the effective degradation at an assumed out flow rate of passage 0.05 h -1 is highest in 0.3% enzyme level but statistically non significant from 0.1% and 0.2% enzyme treated fermented wheat straw and statistically significant from fermented wheat straw only.it is evident that effective degradation values of all the treatments were lower than the true digestible values, indicating that a part of potentially digestible fraction was being prematurely passed out of the rumen along with other digesta. The true digestibility is highest in animals fed 0.3% enzyme treated fermented wheat straw and statistically significant from fermented and 0.1% enzyme treated wheat straw. In the present study, the rumen fill values were highest in group fed fermented wheat straw and lowest in group fed 0.3% enzyme treated fermented wheat straw and is statistically significant as shown TABLE 4: Digestion kinetic parameters of NDF of fermented wheat straw treated with different enzyme levels. Parameters Fermented wheat straw 0.1% Enzyme 0.2% Enzyme 0.3% Enzyme a, % a ± a ± b ± b ± 0.40 b, % c ± b ± a ± a ± 0.21 UDF, % b ± b ± a ± a ± 0.21 ED, % a ± b ± b ± b ± 0.78 TD, % a ± a ± ab ± b ± 1.22 RF,% c ± bc ± ab ± ab ± 0.15 c, h a ± a ± b ± b ± 0.001

6 26 INDIAN JOURNAL OF ANIMAL RESEARCH i n (Table 4). The reason coul d be sl ow fermentation rate that led to higher degree of rumen fill and thus limits the DM intake. Higher rumen fill values were indicative of highest load in rumen and were negatively correlated with voluntary intake. Undegradable fraction is highest in group fed with fermented wheat straw and lowest in group fed 0.3% enzyme treated which is statistically non significant with animals fed 0.2% enzyme treated wheat straw (Table 4). The lower value in group fed 0.3% enzyme treated fermented wheat straw could be because of higher rate of passage. CONCLUSIONS The effect of exogenous fibrolytic enzymes was enhanced when used along with urea treated wheat straw in comparison to untreated wheat straw. This study also concludes that 0.2% exogenous fibrolytic enzyme treatment of wheat straw was the best level. REFERENCES Dean D. B., Adesogan A. T., Krueger N A., Littell R. C.(2007). Effects of treatment with ammonia or fibrolytic enzymes on chemical composition and ruminal degradability of hays produced from tropical grasses. Animal Feed Science and Technology 145: Duncan D. B.,( 1955). Multiple range and multiple F tests. Biometrics 11: 1-42 Kearl L. C,. (1982). Nutrient Requirements of Ruminants in Devloping Countries. International Feedstuffs Institute, Utah Agriculture Experiment Station Utah State University, Logan Utah. McDonald I., (1981). Arevised model for the estimation of protein degradability in the rumen. Journal of Agriculture Science Camb 96: Orskov E. R and McDonald I. (1979). The estimation of protein degradability in the rumen from incubation measurements weighted according to rate of passage. Journal of Agriculture and Science Camb 92: Pinos-Rodruýguez J. M., Morenob R., Gonzalez S. S., Robinson P. H., Mendoza G., lvarez G. A. (2008). Effects of exogenous fibrolytic enzymes on ruminal fermentation and digestibility of total mixed rations fed to lambs. Animal Feed Science and Technology 142: Snedecor G. W and Cochran W. G. (1989). Statistical Methods, 7 th edn. The Iowa State University Press, Ames, Iowa. Wang Y., McAllister T. A., Rode L. M., Beauchemin K. A., Morgavi D. P., Nsereko V. L., Iwaasa A. D and Yang W. (2001). Effects of an exogenous enzyme preparation on microbial protein synthesis, enzyme activity and attachment to feed in the Rumen Simulation Technique (Rusitec). British Journal of Nutrition 85: