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Application and Limitations of Exogenous Fibrolytic Enzymes in Animal Nutrition

Debasish Satapathy Tapas Kumar Dutta Anupam Chatterjee
Vol 8(8), 21-34

Dairy industry and poultry industry in India are facing downfall due to low availability and low digestibility of feeds and forages. Ruminants are fed straw based diet which has a very low digestibility. To increase its digestibility, various exogenous fibrlolytic enzymes can be used like cellulase, xylanase, pectinase, amylase etc. These enzymes either can be applied to the feed prior to feeding to hydrolyze the structural carbohydrates or can be directly fed to animals during feeding. The application of these enzymes may improve digestibility of feed, increase feed intake, which may lead to higher feed efficiency, higher growth rate and higher milk production. But care should be taken regarding selection of enzyme, mode and time of application, concentration of enzyme for optimum activity. Therefore, more research is needed to study the specific enzyme for different substrate instead of using a generalized group of enzyme.

Keywords : Cellulase Fibrolytic Enzyme Nonruminants Ruminants Xylanase

In Indian condition, dairy animals are preferably raised up on low quality native grasses, crop residues and agro-industrial by-products because of low availability of fodder and high cost of concentrates. The green roughage, dry roughage and concentrate are deficit up to 62.76, 23.46 and 63.00% of requirement (Kore, 2014). These feeds are low in energy and protein owing to high fiber, lignin and silica. Ruminant animals have the ability to convert low quality feeds into high quality protein due to ruminal microorganisms that synthesize and secrete β 1-4 cellulase enzyme complex, thereby allowing hydrolysis of plant cell wall components. High fiber content of fibrous feeds prevents the access of ruminal enzymes to the plant cell wall and reduce nutrient digestibility (Abdel-Aziz et al., 2015; Elghandour et al., 2015; Togtokhbayar et al., 2015). The fodders fed to farm animals have high crude fiber and medium digestibility. Thus to improve the digestibility, it is important to break down the linkage between cellulose, hemicellulose and lignin. Digestibility of fiber can be improved by different rumen manipulation techniques. Exogenous enzyme application is one of the rumen manipulation techniques that can be used to improve the digestibility of feeds and improved production performance (Rojo et al., 2015; Salem et al., 2015; Valdes et al., 2015).  In recent years, use of Exogenous Fibrolytic Enzymes (EFE) has been identified as a promising alternative to improve forage utilization by ruminants (Beauchemin et al., 2003). The potential of enzymes to increase the performance of cattle (Bhasker et al., 2012), buffaloes (Gaafar et al., 2010), lambs (Salem et al., 2012) has been reported previously. Apart from that, broiler industry is also going through a crisis of food supply because of high cost of traditional feeds like maize, soyabean meal etc. Therefore, there should be an approach either to provide alternate feed sources which have fewer digestibilities or to increase the digestibility of those feeds. Digestibility of sunflower meal can be increased by use of exogenous enzyme (Alagawany et al., 2015). Alternate feed sources are known to contain many anti nutritional factors, which are harmful to the animals. Therefore, removal of those antinutritional factors either by different chemicals or by use of antidote enzyme is essential in animal nutrition. Chemicals such as NH3, NaOH can be used to improve the digestibility of feeds and remove deleterious factors, but may also lead to huge loss of DM (Lynch et al., 2014). Therefore, use of exogenous fibrolytic enzyme is on high research interest as digestibility of fiber fraction reaches to a maximum level of 65-70% even under ideal condition (Yang et al., 2011; Chung et al., 2012; Mohamed et al., 2013)

Sources of Enzymes

Enzyme products are derived primarily from four bacterial (Bacillus subtilis, Lactobacillus acidophilus, L. plantarum and Streptococcus faecium), three fungal (Aspergillus oryzae, Trichoderma reesei and Saccharomyces cerevisiae) species and some yeasts (Subramaniyam and Vimala, 2012). Enzymes are produced from bacteria and fungi by fermentation process. Fermentation has been classified into Solid State Fermentation (SSF) and Submerged Fermentation (SmF) mainly based on the type of substrate used during fermentation. In solid state fermentation, solid substrates like bran, bagasses are used. In this case, the fermentation takes place in a slow and steady manner but for a very long period which leads to controlled release of nutrients. But in case of submerged fermentation or liquid fermentation process, liquid substrates like broth, molasses are used. These types of substrates are used in a very rate leading to rapid production of enzymes. So the substrates should be replaces or supplemented with nutrient at a faster rate (Subramaniyam and Vimala, 2012).

SmF is usually implemented in case of bacterial enzyme production, due to the requirement of higher water potential (Chahal, 1983). SSF is preferred when enzymes have to be extracted from fungi, which require lesser water potential. More than 75% of the industrial enzymes are produced using SmF. One of the major reason being that SmF supports the utilization of genetically modified organisms to a greater extent than SSF. Fungi produce more cellulase from bacteria still isolation of cellulase from bacteria are now becoming more popular. Because of the following reasons-

  1. Higher growth rate of bacteria
  2. Bacterial cellulase are more complex and provide better function
  3. Bacteria can sustain in highly variable environment (Sujani and Seresinhe, 2015).

Cellulase are produced using both fungi and bacteria with more emphasis on the use of fungi because of their capability to produce ample amounts of enzymes (Subramaniyam and Vimala, 2012) and often less complex than bacterial cellulase and easy for extraction and purification. Bacteria, yeasts and filamentous fungi have been identified as suitable candidates to produce xylanases (Kamble and Jadhav, 2012). According to another study, new xylanase producing Gram positive bacteria has been isolated from termite gut (Matteotti et al., 2012).

Types of Enzymes

The types and activity of enzymes produced can be diverse depending on the strain selected, the substrate they are grown on and the culture conditions used (Gashe, 1992; Lee et al., 1998). A huge number of enzymes are needed for degradation of structural carbohydrate of plant cellwall (Morgavi et al., 2012). Common commercially available enzymes are cellulases and xylanases, but a lot of secondary enzymes are also available in the market like amylases, proteases, esterases, or pectinases. Further carbohydrate breaking enzymes or group of enzymes can be classified as endoglucanases and exoglucanases based up on their site of action (Zhang and Lynd, 2004). For degradation of protein fraction, amylolytic (Noziere et al., 2014; Gencoglu et al., 2010) and proteolytic (Eun and Beauchemin, 2005; Vera et al., 2012) enzymes can also be applied. Fibrolytic enzymes are mainly of two types i.e. for cellulose hydrolysis and for hemicellulose hydrolysis. Enzymes for cellulose hydrolysis are endoglucanase, cellobiohydrolase, β-glucosidase, while enzymes for hemicellulose hydrolysis are endoxylanases, β-1,4-xylosidases. Some other enzymes are also included under fibrolytic enzymes like acetyl xylan esterase, ferulic acid esterase, α-D-glucoronidase, α-L-arabinofuranosidase.

Mechanism of Action of Enzymes

Primary target of exogenous enzymes are cellulose and hemicellulose. Cellulose is a branched complex structure. Therefore, degradation is not simple and needs a group of enzymes. Cellulases are a group of enzymes that hydrolyse cellulose or β-(1,4)-glucan. Enzymes belonging to this class are cellobiohydrolases, endoglucanases and β-glucosidases or cellobiases. Cellobiohydrolases act on crystalline parts of cellulose, whereas endoglucanases are believed to cleave at the amorphous regions of the polymer. These two enzymes produce cellobiose from cellulose. Finally, cellobiose is acted by cellobiase or β-glucosidases to produce glucose that is simple sugar which can be digested or utilized by the animals (Rabinovich et al., 2002).

Xylan is the major component of hemicellulose and is, after cellulose, the second most abundant polysaccharide in nature. Xylans account for 30–35% of the cell wall material of annual plants (grasses and cereals), 15–30% of hardwoods and 7–10% of softwoods. They are also branched compounds, which need a group of enzymes known as xylanases for degradation. Partial hydrolysis of hemicellulose effective for viscosity reduction. However, for complete hydrolysis synergistic action of several xylanases is needed. The side-chain cleaving ‘accessory’ enzymes remove the substituent groups and the 1,4-β-D-xylosidase cleaves xylobiose and xylooligosaccharides into xylose monomers (Shallom and Shoham, 2003). The accessory enzymes for total hydrolysis of arabinoxylan include α-L-arabinofuranosidase, acetyl xylan esterase and feruloylesterase, P- coumaric acid easterase and α-Dglucuronidase. Hydrolysis by xylanases of cereal xylans releases oligosaccharides consisting of xylose or xylose and arabinose residues (Paloheimo et al., 2010).

Application of Enzymes

Application of enzymes can be done through different methods such as pre-treatment on the feeds for a period of time or at the time of feeding or providing directly into the rumen. Which is the best method, is  yet to be finalized. But it can be stated that method of application of enzyme should be selected basing on the type of feed and feed components. Adding enzymes to the feed prior to feeding provides enough time for the enzymatic action on fibrous carbohydrates leading to hydrolysis of the fibers and availability of monomer units to animals.  Yang et al. (2000) reported that fibrolytic enzyme addition to concentrates one month before feeding increased diet digestion and milk production by dairy cows. Again, Shadmanesh (2014) observed increase in milk yield and SNF by feeding TMR mixed with fibrolytic enzyme prior to feeding. However, Lynch et al. (2014) reported no effect of exogenous fibrolytic enzyme application during ensiling of alfalfa on nutritive value, rather more loss of DM when applied along with ferulic acid easterase inoculum.

Effect of Enzymes on Dairy Cattle

Mohamed et al. (2013) reported that supplementing fibrolytic enzyme (with TMR at the time of feeding) to early lactating dairy cows increased milk production significantly without affecting DMI. Supplementing cellulase and xylanase mixture (1:1) @1.5g/kg DM to Sahiwal cows increased the CF and NDF digestibility leading to increased milk production (Miachieo and Thakur, 2007). Gado et al. (2009), Holtshausen et al. (2011) and Arriola et al. (2011) also reported similar results. Klingerman et al. (2009) observed significant increase in milk production without affecting milk fat and milk protein due to supplementation of exogenous fibrolytic enzyme. Tewoldebrhan et al. (2017) also reported improved feed conversion efficiency and lowered somatic cell count without affecting the milk production and milk composition in Holstein cows when supplemented with β-mannanase @ 0.1% of DM. However, a nonsignificant change in milk production was observed by Diler et al. (2014) due to supplementation of direct fed microbials and enzyme mixture. Similar result was also observed by Elwakeel et al. (2007). However, they suggested that slight differences of milk production might be due to repartitioning of energy between milk and body reserves for cows receiving enzymes.

Exogenous fibrolytic enzyme feeding resulted in increased sugar release from fibers leading to increased TVFA concentration, decreased rumen pH. Rumen liquor protein and nitrogen concentration was at optimum concentration by supplementing exogenous fibrolytic enzyme (240mg/kg TMR) which indicated better utilization of carbohydrate and protein in nonpregnant Gir and crossbred dairy cows (Lunagariya et al., 2017). Supplementing exogenous fibrolytic enzymes with corn or sugarcane silage had no significant effect on eating behavior, nutrient intake, rumen fermentation pattern, and microbial protein synthesis. But this supplementation increased NDF digestibility and N absorption of low quality forage like sugarcane silage in dairy cows (Gandra et al., 2017). Similar to this other studies also revealed no effect of fibrolytic enzyme supplementation on feed intake (Peters et al., 2015; Silva et al., 2016). But Romero et al. (2016) reported increased DMI, OMI and CPI due to supplementation of exogenous enzyme (cellulase and xylanase) @ 1ml or 3.4ml per kg Bermuda grass based TMR without affecting the milk composition. Beauchemin and Holt- shausen (2010) suggested that the stage of lactation plays a vital role for effectiveness of exogenous fibrolytic enzyme application in case of dairy cows. Proteolytic enzyme supplementation resulted in increased digestibility of DM, OM however decreased the DMi and Milk yield. Although, dairy efficiency that is milk/DMI was increased (Eun and Beauchemin, 2005).

Effect of Enzymes on Beef Cattle

In case of beef steers, DMI and DMD were found to be increased after due to application of fibrolytic enzyme after harvesting of Bermudagrass (Krueger et al., 2008). In another study by Varges et al. (2013), they reported no effect of fibrolytic enzyme on body weight gain, feed conversion efficiency but improved carcass characteristics and tenderness. Atrian and Shahryar (2012) found that application of fibrolytic enzyme @ 14ml/10kg alfalfa hay had a positive effect on daily gain and DMI. Again they stated that there should be a limitation of application i.e. application @19ml/10kg hay had a negative effect on growth performance. Contradicting to these studies Salem et al. (2011) reported no significant growth in goat due to fibrolytic enzyme supplementation while apparent digestibility of NDF and ADF was increased. A study conducted by Balci et al. (2007) exhibited better daily weight gains, total weight gains and feed conversion rates. Positive effect of fibrolytic enzyme on Barley and wheat based dried distillers grain has been observed by He et al. (2014 and 2015). In an experiment on beef cattle, Romero et al. (2013), reported that digestibility of hay depend on its maturity i.e. 5 week mature hay had higher digestibility while that of 13 week hay had low digestibility even after fibrolytic enzyme application. Russell et al. (2016) reported decreased NDF digestibility and non-differed ADF digestibility of whole shell corn due to addition of enzyme in beef steers.

Effect of Enzymes on Buffaloes

Buffaloes are known to consume more amount of straw and fodder than that of cattle. But, poor utilization capacity of forages by the animal is main constraint in buffalo husbandry. Therefore, there is high need for improving the digestibility of the forages in case of buffaloes. Several experiments have been carried out regarding effect of exogenous fibrolytic enzymes on buffalo performance. Through in vitro experiment, Malik and Bandla (2010) specified a dose of exogenous enzyme and when that dose was supplemented to male buffalo calves along with probiotics, digestibility of OM, ADF and NDF was improved significantly leading to higher ADG and feed efficiency. Nawaz et al. (2016) also reported similar results. However, contradictory result has been observed by Reddy et al. (2016) who reported no effect of exogenous fibrolytic enzyme and live yeast culture on performance of buffalo bulls. Similarly, addition of enzyme to urea treated straw had no effect on digestibility of wheat straw in case of buffalo because of rapid production of ammonia and alkaline pH (Rehman et al., 2014). Thakur et al. (2010) defined the dose of the enzyme (Cellulase and xylanase) in an experiment and suggested that supplementation of enzyme @ 1.5gm/kg DM of TMR had more pronounced effect on growth performance in buffalo as compared to 3gm/ kg DM and non supplemented group. Shekhar et al. (2010) and Mosy et al. (2016) have reported improved nutrient digestibility and higher milk production due to addition of exogenous fibrolytic enzyme in case of Murrah buffalo and Egyptian buffalo, respectively. Supplementation of enzyme decreased the rumen pH, increased the ruminal TVFA, ruminar ammonia and nitrogen fraction which is an indication of better digestibility of feeds (Rajamma et al., 2014).

Effect of Enzymes on Sheep and Goat

In case of goats, supplementation of fibrolytic enzyme with TMR improved NDF and ADF digestibility by 10 and 9.1%, respectively. It also resulted in higher concentration of TVFA and acetate with higher bacterial count. So feed efficiency was found to be higher because of enzyme supplementation (Yuangklang et al., 2017). Bhasker et al. (2013) observed similar rumen fermentation pattern in sheep due to cellulose-xylanase mixture. But they also observed no significant effect on rumen pH, DMI and rumen nitrogen content. Higher growth rate in Mangolian lambs were also observed due to cellulase supplementation by Togtokhbayar et al. (2017). High doses of Exogenous Fibrolytic Enzymes (EFE) (0, 5, 10g/ Kg DM of oat straw) were evaluated for their effects on lamb performance (Bueno et al., 2013). Resulting from enzyme treatment, intake decreased linearly (p<0.04) with increasing enzyme doses without changing the weight gain, feed conversion, digestibility and ruminal fermentation parameters. Similar results of unchanged weight gain and dry matter intake were also evident in the study by Torres et al. (2013). Salix babylonica leaves extract along with enzyme had a pronounced effect on meat quality as compared to enzyme supplementation alone (Cayetano et al., 2013; Valdes et al., 2015). Wang and Xue (2016) also reported no significant effect of enzyme supplementation on nutrient digestibility, nitrogen retention, energy metabolism and methane emission in Boer goats. Contradicting to these Salem et al. (2015) reported improved feed intake, nutrient digestibility, nitrogen balance and rumen fermentation pattern in case of sheep, due to supplementation of Atriplex halimu and enzyme cocktail.

Exogenous enzyme supplementation may lead to increased feed intake and digestibility of forages leading to increased weight gain. This has been supported by Mijinyawa et al. (2016), who observed increased feed intake, weight gain and average daily gain in bucks fed sugarcane bagasse with enzyme supplementation were significantly (p<0.05). Nutrients digestibility followed similar pattern except for Dry matter (DM), CP and CF which were not significant. They concluded that urea treatment with enzyme supplementation has positive effect on performance of fattening Red Sokoto bucks. Another study was conducted to investigate the effects of adding cellulolytic enzyme “Asperozym” or Tomoko® to the diets on the performance of goats. The diets supplemented with either enzymes showed significantly (p<0.05) increased digestibility of all nutrients with significant effect on rumen liquor parameters (Kholif and Aziz, 2014).

Effect of Enzymes on Non-Ruminant Animals

In an experiment on growing pigs, Schertz et al. (2016) reported 7% faster growth rate (p=0.03) due to supplementation of exogenous enzyme with protease and carbohydrase activity. Lu et al. (2016) also reported higher body weight gain, ADG and apparent total tract digestibility because of supplementation of xylanase, β-glucanase and phytase. Contradicting to this, O’shea et al. (2014) reported no effect of xylanase and protease on pigs, which are fed diets based on rapeseed meal, and dried distillers grain despite of higher ileal digestibility. They suggested that that this might be due to lower average daily feed intake. Yang et al. (2017) reported that supplementing xylanase improved the crude protein digestibility while phytase supplementation improved digestibility of calcium and phuophorus. However, supplementing both enzymes impaired the effectiveness of xylanase leading to reduced NDF digestibility. This might be due to alteration in hindgut flora composition because of phytate that led to deactivate xylanase.

In case of poultry birds, exogenous enzyme supplementation is needed to increase the feeding value of raw materials, to reduce the variation in nutrient quality of ingredients and to reduce the incidence of wet litter (Bedford, 2000). Broiler farmers are taking a step back from feeding soyabean meal to birds because of its high cost. Therefore, unconventional feed for protein sources are being used. One of the unconventional feed is sunflower meal (SFM). Alagawany et al. (2017) reported that SFM could replace soyabean meal up to 50% with addition of exogenous enzyme (xylanase, protease and amylase) and could provide improved growth performance, activity of digestive enzymes and carcass traits. Nikam et al. (2016 and 2017) also suggested that using of enzymes like xylanase, ß-D-glucanase, cellulase, mannanase and pectinase to diets based on guarmeal, rapeseed meal, cottonseed meal improves body weight gain and feed intake. Naik et al. (2017) and Santhi et al. (2014) have observed similar results of exogenous enzyme supplementation on broilers and turkey, respectively.

Limitations or Challenges for Use of Exogenous Enzyme

Though use of exogenous enzymes have a lot of advantages, its use is limited because of its price and again some scientists reported no effect of this type of supplementation in animals fed with concentrate based diet. Before use of enzymes, some basic knowledge regarding enzyme and substrate should be acquired for optimum result.

Specificity of the Exogenous fibrolytic Enzyme to the Substrate

A particular enzyme can break a specific linkage. Therefore, enzymes are feed specific according to their chemical structure. Example- Enzymes effective for improving dry matter digestibility of corn silage were different from enzymes required for alfalfa hay digestion (Colombatto et al., 2003).

Time of Application

As discussed earlier time of application of enzyme for optimum action is essential. Whether the enzyme should be fed to to the animal during feeding or application of enzyme should be done on the feed just before feeding should be analyzed as per the type of feed.

Rate and Level of Enzyme Application

Low dose of enzyme application may not exploit its optimum hydrolytic potential. Similarly overdose also may lead to molecular crowding leading to decreased dry matter intake and digestibility. (Bommarious et al., 2008). Optimum level of enzyme should be applied on the feed and when used in combination, optimum ratio of enzymes should be identified for optimum result (Thakur et al., 2008)

Influence of pH and Temperature

Enzyme activity is pH specific and enzyme activity reaches its optimum potential at a particular range of temperature. By studing the effect of 18 commercially available endoglucanase and xylanase at different temperatures and pH, Adesogan et al. (2014) reported that 78 and 83% of the these enzymes exhibited endoglucanase and xylanase activity at 50°C, however, 77 and 61% had optimal activity at pH 4 to 5, respectively.

Inappropriate Choice

Choice of enzyme for hydrolysis of structural carbohydrate should be substrate specifc. Inappropriate choice of enzyme may hydrolyse other available sugars leading to less effectiveness of feed. Some exogenous fibrolytic enzymes were developed for other applications such as textiles, food, nonruminant diets or paper. Therefore, such EFE often lack sufficient potency and specificity for improving the use of fibrous ruminant feeds (Adesogan et al., 2014).


Exogenous enzymes can be used in ruminant and non-ruminant nutrition in an appropriate way and at roper concentration to improve the feed utilization capacity of animal, to improve the digestibility of feed, to improve the growth rate and weight gain and also to improve the milk production. Appropriate choice of the enzyme should be done basing on the target feed chemical composition of target feed. Future studies can be carried out giving emphasis on enzyme specificity and enzyme mode of action.


  1. Abdel-Aziz NA, Salem AZM, El-Adawy MM, Camacho LM, Kholif AE, Elghandour MMY and Borhami BE. 2015. Biological treatments as a mean to improve feed utilization in agriculture animals-An overview. Journal of Integrative Agriculture. 14: 534–43.
  2. Adesogan AT, Ma ZX, Romero JJ, Arriola KG. 2014. Ruminant nutrition symposium: Improving cell wall digestion and animal performance with fibrolytic enzymes. Journal of animal science. 92(4):1317-30.
  3. Alagawany M, Attia AI, Ibrahim ZA, Mahmoud RA, El-Sayed SA. 2017. The effectiveness of dietary sunflower meal and exogenous enzyme on growth, digestive enzymes, carcass traits, and blood chemistry of broilers. Environmental Science and Pollution Research. 24(13):12319-27.
  4. Alagawany M, Farag MR, Abd El-Hack ME, Dhama K. 2015. The practical application of sunflower meal in poultry nutrition. Advances in Animal and Veterinary Science. 3:634–648
  5. Arriola KG, Kim SC, Staples CR and Adesogan AT. 2011. Effect of fibrolytic enzyme application to low-and high-concentrate diets on the performance of lactating dairy cattle. Journal of Dairy Science. 94(2):832-841.
  6. Atrian P and Shahryar HA. 2012. Effect of fibrolytic enzyme treated alfalfa on performance in Holstein beef cattle. European Journal of Experimental Biology. 2(1):270-273.
  7. Balci F, Dikmen S, Gencoglu H, Orman A, Turkmen II, Biricik H. 2007. The effect of fibrolytic exogenous enzyme on fattening performance of steers. Bulgarian Journal of Veterinary Medicine. 10(2):113-118.
  8. Beauchemin KA and Holtshausen L. 2010. Developments in enzyme usage in ruminants. Enzymes in farm animal nutrition. 206-230.
  9. Beauchemin KA, Colombatto D, Morgavi DP and Yang WZ. 2003. Use of Exogenous Fibrolytic Enzymes to Improve Feed Utilization by Ruminants. Journal of Animal Science. 81: 37-47.
  10. Bedford MR. 2000. Exogenous enzymes in monogastric nutrition—their current value and future benefits. Animal Feed Science and Technology. 86(1):1-3.
  11. Bhasker TV, Nagalakshmi D and Rao DS .2012. Exogenous Fibrolytic Enzyme Cocktail for Improvement of Nutrient Utilization from Sorghum Stover in Cattle. Indian Journal of Dairy Science. 65: 324-328.
  12. Bhasker TV, Nagalakshmi D and Rao DS. 2013. Development of appropriate fibrolytic enzyme combination for maize stover and its effect on rumen fermentation in sheep. Asian-Australasian journal of animal sciences, 26(7):945.
  13. Bommarius AS, Katona A, Cheben SE, Patel AS, Ragauskas AJ, Knudson K, Pu Y. 2008 Cellulase kinetics as a function of cellulose pretreatment. Metabolic engineering. 10(6):370-381.
  14. Bueno AL, Martínez GM, García PH, García JM and Pérez FP. 2013. Evaluation of high doses of exogenous fibrolytic enzymes in lambs fed an oat straw based ration. Animal Nutrition and Feed Technology, 13(3):355-362.
  15. Cayetano JA, Salem AZM, Mariezcurrena BMA, Rojo R, Cerrillo-Soto MA, Gado H and Camacho LM. 2013. Effect of adding Salix babylonica extracts and exogenous enzymes to basal diets on the meat quality of growing Suffolk lambs.
  16. Chahal, DS. 1983. Foundations of Biochemical Engineering Kinetics and Thermodynamics in Biological Systems. In ACS Symposium Series. 207:42.
  17. Chung YH, Zhou M, Holtshausen L, Alexander TW, McAllister TA, Guan LL, Oba M, Beauchemin KA. 2012. A fibrolytic enzyme additive for lactating Holstein cow diets: Ruminal fermentation, rumen microbial populations, and enteric methane emissions. Journal of dairy science. 95(3):1419-1427.
  18. Colombatto D, Morgavi DP, Furtado AF and Beauchemin KA. 2003. Screening of exogenous enzymes for ruminant diets: Relationship between biochemical characteristics and in vitro ruminal degradation. Journal of Animal Science. 81(10):2628-2638.
  19. Diler A, Kocyigit R, Yanar M and Aydin R. 2014. Effect of feeding direct-fed microbials plus exogenous feed enzymes on milk yield and milk composition of holstein friesian cows. Veterinarija ir Zootechnika. 65(87): 11-16.
  20. Elghandour MMY, Salem AZM, Martínez Castañeda JS, Camacho LM, Kholif AE and Vázquez Chagoyán JC. 2015. Direct-fed microbes: A tool for improving the utilization of low quality roughages in ruminants. Journal of Integrative Agriculture. 14: 526–33.
  21. Elwakeel EA, Titgemeyer EC, Johnson BJ, Armendariz CK and Shirley JE. 2007. Fibrolytic enzymes to increase the nutritive value of dairy feedstuffs. Journal of Dairy Science. 90(11):5226-5236.
  22. Eun JS, Beauchemin KA. 2005. Effects of a proteolytic feed enzyme on intake, digestion, ruminal fermentation, and milk production. Journal of dairy science. 88(6):2140-2153.
  23. Gaafar HMA, Abdel Raouf EM and El Reidy KFA. 2010. Effect of Fibrolytic Enzyme Supplementation and Fiber Content of Total Mixed Ration on Productive Performance of Lactating Buffaloes. Slovak Journal of Animal Science. 43: 147-153.
  24. Gado HM, Salem AZM, Robinson PH and Hassan M. 2009. Influence of exogenous enzymes on nutrient digestibility, extent of ruminal fermentation as well as milk production and composition in dairy cows. Animal Feed Science and Technology. 154(1): 36-46.
  25. Gandra JR, Miranda GA, Goes RH, Takiya CS, Del Valle TA, Oliveira ER, Junior JF, Gandra ER, Araki HM and Santos AL. 2017. Fibrolytic enzyme supplementation through ruminal bolus on eating behavior, nutrient digestibility and ruminal fermentation in Jersey heifers fed either corn silage-or sugarcane silage-based diets. Animal Feed Science and Technology231: 29-37
  26. Gashe BA. 1992. Cellulase production and activity by Trichoderma sp. A‐Journal of Applied Microbiology. 73(1): 79-82.
  27. Gencoglu H, Shaver RD, Steinberg W, Ensink J, Ferraretto LF, Bertics SJ, Lopes JC, Akins MS. 2010. Effect of feeding a reduced-starch diet with or without amylase addition on lactation performance in dairy cows. Journal of dairy science. 93(2):723-732.
  28. He ZX, He ML, Walker ND, McAllister TA and Yang WZ. 2014. Using a fibrolytic enzyme in barley-based diets containing wheat dried distillers grains with solubles: ruminal fermentation, digestibility, and growth performance of feedlot steers. Journal of animal science. 92(9):3978-3987.
  29. He ZX, Walker ND, McAllister TA and Yang WZ. 2015. Effect of wheat dried distillers grains with solubles and fibrolytic enzymes on ruminal fermentation, digestibility, growth performance, and feeding behavior of beef cattle. Journal of animal science. 93(3): 1218-1228.
  30. Holtshausen L, Chung YH, Gerardo-Cuervo H, Oba M and Beauchemin KA. 2011. Improved milk production efficiency in early lactation dairy cattle with dietary addition of a developmental fibrolytic enzyme additive. Journal of Dairy Science. 94(2):899-907.
  31. Kamble RD, Jadhav AR. 2012. Isolation, identification and screening of potential cellulase-free xylanase producing fungi and its production. African Journal of Biotechnology. 11(77):14175-14181.
  32. Kholif AM and Aziz HA. 2014. Influence of feeding cellulytic enzymes on performance, digestibility and ruminal fermentation in goats. Animal Nutrition and Feed Technology. 14(1): 121-136.
  33. Klingerman CM, Hu W, McDonell EE, DerBedrosian MC and Kung L. 2009. An evaluation of exogenous enzymes with amylolytic activity for dairy cows. Journal of dairy science. 92(3):1050-9.
  34. Kore KB. 2014. Fodder production and grassland management. In: Farm Animal Management, Principal and Practices. Singh, R.R. and Islam, M.M. (Edr), New India Publishing Agency, New Delhi, India.
  35. Krueger NA, Adesogan AT, Staples CR, Krueger WK, Kim SC, Littell RC and Sollenberger LE. 2008. Effect of method of applying fibrolytic enzymes or ammonia to Bermudagrass hay on feed intake, digestion, and growth of beef steers. Journal of animal science. 86(4): 882-889.
  36. Lee B, Pometto AL, Demirci A and Hinz PN. 1998. Media evaluation for the production of microbial enzymes. Journal of agricultural and food chemistry.46(11): 4775-4778.
  37. Lu H, Preynat A, Legrand-Defretin V, Geraert PA, Adeola O, Ajuwon KM. 2016. Effects of dietary supplementation of exogenous multi-enzyme mixture containing carbohydrases and phytase on growth performance, energy and nutrient digestibility, and selected mucosal gene expression in the small intestine of weanling pigs fed nutrient deficient diets. Canadian Journal of Animal Science. 96(2):243-51.
  38. Lunagariya PM, Shah SV, Gupta RS, Parnerkar S, Pansuriya H, Khaire K and Patel GR. 2017. Effect of Supplementation of Exogenous Fibrolytic Enzymes in Total Mixed Ration on Rumen Fermentation Pattern in Dairy Cows. The indian journal of veterinary sciences and biotechnology. 12(3).
  39. Lynch JP, Jin L, Lara EC, Baah J and Beauchemin KA. 2014. The effect of exogenous fibrolytic enzymes and a ferulic acid esterase-producing inoculant on the fibre degradability, chemical composition and conservation characteristics of alfalfa silage. Animal Feed Science and Technology. 193:21-31.
  40. Lynch JP, O’kiely P, Murphy R, Doyle EM. 2014. Changes in chemical composition and digestibility of three maize stover components digested by white‐rot fungi. Journal of animal physiology and animal nutrition. 98(4):731-738.
  41. Malik R and Bandla S. 2010. Effect of source and dose of probiotics and exogenous fibrolytic enzymes (EFE) on intake, feed efficiency, and growth of male buffalo (Bubalus bubalis) calves. Tropical Animal Health and Production. 42(6): 1263-1269.
  42. Mattéotti C, Bauwens J, Brasseur C, Tarayre C, Thonart P, Destain J, Francis F, Haubruge E, De Pauw E, Portetelle D and Vandenbol M. 2012. Identification and characterization of a new xylanase from Gram-positive bacteria isolated from termite gut (Reticulitermes santonensis). Protein expression and purification. 83(2):117-27.
  43. Miachieo K and Thakur SS. 2007. Effect of exogenous fibrolytic enzymes on the productive performance of lactating Sahiwal cows. Indian Journal of Animal Nutrition. 24(1):27-30.
  44. Mijinyawa MA, Lamidi OS, Abdu SB, Umar H, Muhammad HA and Bala AG. 2016. Effect of treated and untreated sugarcane bagasse with or without enzyme supplementation in total mixed ration on performance of red Sokoto bucks. Journal of Animal Production Research. 28(2): 150-160.
  45. Mohamed DE, Borhami BE, El-Shazly KA, Sallam SM. 2013. Effect of dietary supplementation with fibrolytic enzymes on the productive performance of early lactating dairy cows. Journal of Agricultural Science. 5(6):146.
  46. Morgavi DP, Kelly WJ, Janssen PH and Attwood GT. 2013. Rumen microbial (meta) genomics and its application to ruminant production. Animal. 7(1): 184-201.
  47. Morsy TA, Kholif AE., Kholif SM, Kholif AM, Sun X and Salem AZ, 2016. Effects of two enzyme feed additives on digestion and milk production in lactating Egyptian buffaloes. Annals of Animal Science. 16(1): 209-222.
  48. Naik RP, Reddy AR, Reddy KK, Jyothi J. 2017. Effect of Encapsulated Amylase Enzyme on the Performance and Digestibility of Energy in Broilers. International Journal of Current Microbiologyand Applied 6(3):2098-2104.
  49. Nawaz H, Shahzad N, Saif-ur-Rehman M and Ali M. 2016. Effect of feeding xylanase and cellulase treated oat silage on nutrient digestibility, growth performance and blood metabolites of Nili Ravi buffalo calves. Pakistan Journal of Agricultural Sciences. 53(4).
  50. Nikam MG, Reddy VR, MVLN R, Reddy KK, Narasimha J. 2016. Effect of Dietary Supplementation of Non Starch Polysaccharide Hydrolyzing Enzymes on Broilers. International Journal of Agricultural Science and Research. 6(3): 389-396.
  51. Nikam MG, Reddy VR, Raju MV, Reddy KK, Narasimha J. 2017. Effect of Dietary Supplementation of Non Starch Polysaccharide Hydrolyzing Enzymes on Performance of Broilers Fed Diets Based on Guar Meal, Rape Seed Meal and Cotton Seed Meal. International Journal of Livestock Research. 7(2):180-190.
  52. Nozière P, Steinberg W, Silberberg M, Morgavi DP. 2014. Amylase addition increases starch ruminal digestion in first-lactation cows fed high and low starch diets. Journal of dairy science. 97(4):2319-2328.
  53. O’Shea CJ, Mc Alpine PO, Solan P, Curran T, Varley PF, Walsh AM, Doherty JV. 2014. The effect of protease and xylanase enzymes on growth performance, nutrient digestibility, and manure odour in grower–finisher pigs. Animal Feed Science and Technology. 189:88-97.
  54. Paloheimo M, Piironen J and Vehmaanperä J. 2010. Xylanases and cellulases as feed additives. Enzymes in Farm Animal Nutrition (2nd Edition). 12-53.
  55. Peters A, Meyer U, Dänicke S. 2015. Effect of exogenous fibrolytic enzymes on performance and blood profile in early and mid-lactation Holstein cows. Animal Nutrition. 1(3):229-38.
  56. Rabinovich ML, Melnick MS and Bolobova AV. 2002. The structure and mechanism of action of cellulolytic enzymes. Biochemistry (Moscow). 67(8): 850-871.
  57. Rajamma K, Kumar DS, Rao ER and Nath DN. 2015. In vitro evaluation of total mixed rations containing different roughage-concentrate ratios supplemented with or without fibrolytic enzymes. Animal Science. 9(2):63-69.
  58. Rajamma K, Srinivas Kumar D, Raghava Rao E and Narendra Nath D. 2014. Effect of fibrolytic enzymes supplementation on rumen fermentation of buffalo bulls fed total mixed rations. International Journal of Agricultural Sciences and Veterinary Medicine. 2: 106-113.
  59. Reddy PR, Kumar DS, Rao ER and Rao KA. 2016. Nutritional Evaluation of Total Mixed Rations Supplemented with Exogenous Fibrolytic Enzymes and/or Live Yeast Culture in Buffalo Bulls. Indian Journal of Animal Nutrition. 33(1): 54-58.
  60. Rehman AU, Nisa MU, Shazad A, Sarwar M, Khan OA and Sharif M. 2014. Chemical composition and digestion kinetics of urea-molasses treated wheat straw ensiled with fibrolytic enzyme in ruminally cannulated buffalo bulls. Journal of animal and plant sciences. 24: 36-39.
  61. Rojo R, Kholif AE, Salem AZM, Elghandour MMY, Odongo NE, De Oca, RM, Rivero N and Alonso MU. 2015. Influence of cellulase addition to dairy goat diets on digestion and fermentation, milk production and fatty acid content. The Journal of Agricultural Science, 153(8): 1514-1523.
  62. Romero JJ, Macias EG, Ma ZX, Martins RM, Staples CR, Beauchemin KA and Adesogan AT. 2016. Improving the performance of dairy cattle with a xylanase-rich exogenous enzyme preparation. Journal of dairy science. 99(5):3486-3496.
  63. Romero JJ, Zarate MA, Queiroz OC, Han JH, Shin JH, Staples CR, Brown WF, Adesogan AT. 2013. Fibrolytic enzyme and ammonia application effects on the nutritive value, intake, and digestion kinetics of bermudagrass hay in beef cattle. Journal of animal science. 91(9):4345-4356.
  64. Russell JR, Sexten WJ and Kerley MS. 2016. Soybean hull and enzyme inclusion effects on diet digestibility and growth performance in beef steers consuming corn-based diets. Journal of animal science. 94(6): 2436-2440.
  65. Salem AZ, Alsersy H, Camacho LM, El-Adawy MM, MMY Elghandour M, Kholif AE, Rivero N, Alonso MU, Zaragoza A. 2015. Feed intake, nutrient digestibility, nitrogen utilization, and ruminal fermentation activities in sheep fed Atriplex halimus ensiled with three developed enzyme cocktails. 60(4): 185–194.
  66. Salem AZ, El-Adawy M, Gado H, Camacho LM, González-Ronquillo M, Alsersy H and Borhami B. 2011. Effects of exogenous enzymes on nutrients digestibility and growth performance in sheep and goats. Tropical and Subtropical Agroecosystems.;14(3):867-874.
  67. Salem AZM, Hassan AA, Khalil MS, Gado HM, Alsersy H and Simbaya J. 2012. Effects of Sun-Drying and Exogenous Enzymes on Nutrients Intake, Digestibility and Nitrogen Utilization in Sheep Fed Atriplex Halimus Foliages. Animal Feed Science and Technology. 171: 128-135.
  68. Santhi D, Thyagarajan D and Ramesh,J. 2014. Effect of exogenous cellulase supplementation in feed on turkey poult performance. Indian Veterinary Journal. 91(02): 9-11.
  69. Schertz LJ, Apgar GA, Lekatz LA, Lammers PJ. 2016. 303 Effect of feeding grower-finisher pig diets containing 20% soybean hulls with or without enzyme supplementation. Journal of Animal Science. 94(supplement 2):142.
  70. Shadmanesh A. 2014. Effect of dietary suppplement with fibrolytic enzymes on the productive performance of early lactating dairy cows. Indian Journal of Fundamental and Applied Life Sciences. 4(2): 396-401
  71. Shallom, D. and Shoham, Y. 2003. Microbial hemicellulases. Current Opinion in Microbiology. 6: 219–228.
  72. Shekhar C, Thakur SS and Shelke SK, 2010. Effect of exogenous fibrolytic enzymes supplementation on milk production and nutrient utilization in Murrah buffaloes. Tropical animal health and production. 42(7): 1465-1470.
  73. Silva TH, Takiya CS, Vendramini TH, de Jesus EF, Zanferari F and Rennó FP. 2016. Effects of dietary fibrolytic enzymes on chewing time, ruminal fermentation, and performance of mid-lactating dairy cows. Animal Feed Science and Technology. 221:35-43.
  74. Subramaniyam R and Vimala R. 2012. Solid state and submerged fermentation for the production of bioactive substances: a comparative study. International journal of science and nature.3: 480-486.
  75. Sujani S and Seresinhe RT. 2015. Exogenous enzymes in ruminant nutrition: A review. Asian journal of animal sciences. 9(3):85-99.
  76. Tewoldebrhan TA, Appuhamy JADRN, Lee JJ, Niu M, Seo S, Jeong S and Kebreab E. 2017. Exogenous β-mannanase improves feed conversion efficiency and reduces somatic cell count in dairy cattle. Journal of Dairy Science. 100(1): 244-252.
  77. Thakur SS, Tomar SK, Sirohi SK. 2008. In vitro DM and Cell wall degradability of total mixed rations influenced by exogenous fibrolytic enzymes supplementation. Indian Journal of Animal Nutrition. 25(3):219-23.
  78. Thakur SS, Verma MP, Babar A, Shelke SK. and Tomar SK, 2010. Effect of exogenous fibrolytic enzymes supplementation on growth and nutrient utilization in Murrah buffalo calves. Indian Journal of Animal Sciences. 80(12): 1217-1219.
  79. Togtokhbayar N, Cerrillo MA, Rodríguez GB, Elghandour MMY, Salem AZM, Urankhaich C, Jigjidpurev S, Odongo NE, Kholif AE. 2015. Effect of exogenous xylanase on rumen in vitro gas production and degradability of wheat straw. Animal Science Journal. 86: 765–71.
  80. Togtokhbayar N, Urankhaich C, Ayushjav O, Tsevegmed M and Odongo NE. 2017. Effects of exogenous cellulase and xylanase enzyme preparations on feed intake, nutrient digestibility, growth, and economics of rearing Mongolian lambs. Journal of Agriculture and Rural Development in the Tropics and Subtropics (JARTS). 118(1): 81-89.
  81. Torres N, Mendoza GD, Bárcena R, Loera O, González S, Aranda E, Hernández PA and Crosby M. 2013. Effects of various fibrolytic enzyme extracts on digestibility and productive performance of lambs fed a forage-based diet. Animal Nutrition and Feed Technology. 13: 381-389.
  82. Valdes KI, Salem AZM, Lopez S, Alonso MU, Rivero N, Elghandour MMY, Domínguez IA, Ronquillo MG and Kholif AE. 2015. Influence of exogenous enzymes in presence of Salix babylonica extract on digestibility, microbial protein synthesis and performance of lambs fed maize silage. The Journal of Agricultural Science. 153(4): 732-742.
  83. Vargas JM, Mendoza GD, Rubio-Lozano MD and Castrejón FA. 2013. Effect of exogenous fibrolytic enzymes on the carcass characteristics and performance of grain-finished steers. Animal Nutrition and Feed Technology. 13(3):435-439.
  84. Vera JM, Smith AH, ZoBell DR, Young AJ and Eun JS. 2012. Effects of an exogenous proteolytic enzyme on growth performance of beef steers and in vitro ruminal fermentation in continuous cultures1. The Professional Animal Scientist. 28(4):452-63.
  85. Wang L and Xue B. 2016. Effects of Cellulase Supplementation on Nutrient Digestibility, Energy Utilization and Methane Emission by Boer Crossbred Goats. Asian-Australasian journal of animal sciences. 29(2): 204.
  86. Yang HE, Son YS, Beauchemin KA. 2011. Effects of exogenous enzymes on ruminal fermentation and degradability of alfalfa hay and rice straw. Asian-Australasian Journal of Animal Sciences. 24(1):56-64.
  87. Yang WZ, Beauchemin KA and Rode LM. 2000. A Comparison of Methods of Adding Fibrolytic Enzymes to Lactating Cow Diets1. Journal of Dairy Science. 83(11):2512-2520.
  88. Yang YY, Fan YF, Cao YH, Guo PP, Dong B and Ma YX. 2017. Effects of exogenous phytase and xylanase, individually or in combination, and pelleting on nutrient digestibility, available energy content of wheat and performance of growing pigs fed wheat-based diets. Asian-Australasian journal of animal sciences. 30(1):57-63.
  89. Yuangklang C, Schonewille JT, Alhaidary A, Vasupen K, Bureenok S, Seanmahayak B, Wongsuthavas S and Beynen AC. 2017. Growth performance and macronutrient digestion in goats fed a rice straw based ration supplemented with fibrolytic enzymes. Small Ruminant Research. 154: 20-26.
  90. Zhang YH and Lynd LR. 2004. Toward an aggregated understanding of enzymatic hydrolysis of cellulose: noncomplexed cellulase systems. Biotechnology and bioengineering. 88(7):797-824.
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