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The Influence of Exogenous Multienzyme Preparation and Graded Levels of Digestible Lysine in Sunflower Meal-Based Diets on the Performance of Young Broiler Chicks Two Weeks Posthatching

T. Mushtaq^*,1, M. Sarwar^*, G. Ahmad, M. U. Nisa^* and A. Jamil

^* Institute of Animal Nutrition and Feed Technology, and Department of Chemistry, University of Agriculture, Faisalabad, Pakistan 38040; Sadiq Brothers Poultry, Rawalpindi, Pakistan 46000

¹ Corresponding author: tmmirza{at}fsd.paknet.com.pk

	ABSTRACT

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The study was conducted to investigate the effect of adding multienzyme preparation (Rovabio Excel AP, Adisseo Asia Pacific Pte Ltd., Singapore) at 2 inclusion levels of sunflower meal (SFM; 20 and 30% of the diets) with 3 levels of digestible Lys (0.8, 0.9, and 1.0%) with and without enzyme in a 2 x 2 x 3 factorial arrangement. Each diet was offered to 4 replicates of 51 one-day-old straight-run Hubbard broiler chicks (n = 2448) in a practical vegetable-based mash diet having 2,750 kcal of ME/kg and 19% CP during 2 wk posthatching (1 to 14 d of age). Feed formulation was based on digestible amino acids, which were calculated from the CP and DM contents of each ingredient using AminoDat 2 (Degussa Corp., Allendale, NJ). The enzyme used in this study was authenticated by the supplier to have minimum level of endo-1,4-ß xylanase (22,000 visco units/g) and endo-1,3(4)-ß glucanase (2,000 AGL units/g) and was added at the rate of 50 mg/kg of finished diet. No significant effect of enzyme or level of SFM was observed on BW gain (BWG), feed intake, or mortality during the experimental period. The BWG and feed:gain for birds fed on 30% SFM with enzyme were comparable to those fed on 20% SFM without enzyme during 1 to 14 d of age. However, enzyme at 20% SFM depressed the BWG (P 0.006) and feed conversion ratio (P 0.027). A quadratic (P 0.036) response of digestible Lys was noted for BWG, whereas it was linear (P 0.001) for feed:gain during 1 to 7 and 1 to 14 d. A level of 1.0% digestible Lys was observed best for BWG and feed:gain. For BWG, 0.8 and 0.9% digestible Lys was comparable when it was used at 30% SFM, along with enzyme. In conclusion, enzyme supplementation during 2 wk posthatching has no remarkable effect when used in SFM-based diets. Moreover, digestible Lys may be lowered to 0.8% during the first week but not less than 1.0% during the second week post-hatching.

Key Words: enzyme supplementation • digestible lysine level • sunflower meal • young broiler

	INTRODUCTION

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Growth of broilers during the first week of life plays an important role in subsequent growth and performance. Hence, the trend is now shifting from starting diets to prestarting diets for attaining desired BW in less time. These high growth rates can only be achieved by using quality dietary protein ingredients. Among the protein sources, soybean meal (SBM) is considered as an excellent protein source due to its good amino acid (AA) profile and high digestibility values (Leeson and Summers, 2001). However, in countries like Pakistan, where SBM is not cultivated and must be imported for use in animal feeds, its use at higher levels is limited due to economical reasons.

Sunflower has a great capability to adapt to different climatic and soil conditions and is, therefore, cultivated worldwide for oil extraction (Ravindran and Blair, 1992). Sunflower meal (SFM), the byproduct rendered by the oil industry, is used as a protein source in animal nutrition. Sunflower meal has a variable CP content (29 to 45%), depending on the dehulling and oil extraction process in inverse relation to its fiber contents [32 to 14% crude fiber (CF)]. However, its use in poultry feed is limited due to its high fiber and Lys deficiency in addition to its low digestion coefficient for Lys (Villamide and San Juan, 1998).

Recent reliance on vegetable proteins in poultry diets offers some challenges, particularly for younger birds in terms of their digestibility as a result of higher fiber content, complex protein structure, and, in some cases, residual antinutrients that lead to poor nutrient utilization. Digestive enzyme activities (units/kg of BW) measured in the pancreas and intestinal contents increases with age (Nitsan et al., 1991). The development of secretion of digestive enzymes in the posthatched chick could also be a limiting factor in digestion and, subsequently, in food intake (Krogdahl and Sell, 1989; Noy and Sklan, 1995; Sklan, 2001), leading to inefficient growth by birds, poor feed conversion ratios, and poor livability. The insufficient enzyme activity for early chicks may possibly be complemented through exogenous enzyme supplementation to promote digestion and utilization of diets.

The NRC (1994) has lowered the required level of total dietary Lys for 1- to 21-d-old chicks from 1.20 to 1.10% of diet. The same AA requirements cannot be applied to all birds under all dietary, environmental, and body-compositional conditions, but the ideal ratios among them remain similar, and, thus, an accurate requirement for Lys needs to be established (Baker and Han, 1994; Baker et al., 2002). Sklan and Noy (2003) estimated the digestible Lys requirements as 0.92 and 0.96% for BW and feed efficiency at 7 d of age. The estimate, however, did not differ greatly from the NRC (1994) requirements for 0 to 21 d of age, which was 1.10% total Lys or 0.97% digestible Lys (assuming 88% digestible Lys in a corn-SBM diet). Halvey el al. (2000) reported that early starvation in chicks affects the dynamics of satellite cells’ (myogenic precursor cells) proliferation and, ultimately, muscle growth of birds. The bird responses during 7 d post-hatching remains the same in later stages, even if the dietary specification changes), possibly due to both changes in lipogenesis and altering plasma insulin-like growth factor I concentration (Rosebrough et al., 1996).

Most of the studies on exogenous enzyme supplementation and AA requirements conducted during the past decades that addressed the young birds’ response for the starter phase (0 to 21 d of age) did not consider the first week posthatching when the yolk sac is present to meet the birds’ nutritional requirements, and digestive enzyme activities are insufficient to properly digest the diets having complex nutrients. The present study, therefore, was conducted to investigate the effect of multienzyme supplementation at 2 inclusion levels of SFM and 3 levels of digestible Lys, with the applicability of the ideal AA ratio concept for better nutrient utilization that could be reflected in live bird’s performance in diets having lower CP and ME than those recommended by the NRC (1994).

	MATERIALS AND METHODS

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Birds and Management
All the experimental procedures were approved by the Ethics Committee of the University of Agriculture, Faisalabad, Pakistan. A total of 2,448 one-day-old straight-run Hubbard broiler chicks were obtained from a local hatchery and were randomly allotted to 1 of 48 floor pens (51 birds in each replicate) with rice straw as bedding material over a concrete floor. A floor space of 0.074 m² was allotted for 1 bird in a 9.29 x 2.79 m open-sided house having movable sidewall curtains. Each pen was equipped with 1 tube feeder and 1 manual drinker. On 11 d of age, the tube feeder was replaced with a round-bottom feeder. The house temperature was maintained at 32.2°C during the first week of age and 29.5°C during the second week of age. Birds were vaccinated for infectious bronchitis at 2 d of age, for Newcastle disease at 4 d, and for infectious bursal disease at 8 d of age. Birds were revaccinated for Newcastle disease at 11 d of age and for infectious bursal disease at 14 d of age. A 24-h continuous light was provided throughout the experiment.

Experimental Diets and Bird Performance
All ingredients used in this study were obtained from a commercial feed mill (SB Feed Mills, Islamabad, Pakistan). The SFM had 32% CP, 20.5% CF, 3.54% ether extract, 1.39% ash, and 1,288 kcal of ME/kg. Two levels of SFM, 20 and 30%, were used with 3 levels of digestible Lys (0.8, 0.9, and 1.0%) in a factorial design of 2 x 3 in 6 dietary combinations in isonitrogenous and isoenergetic diets (Table 1). Total and digestible AA were calculated from analyzed DM and CP contents of each ingredient using AminoDat 2.0 (Degussa Corp., Allendale, NJ). However, feed formulation was based on digestible AA. The ME value of each ingredient was calculated by a regression equation provided by the NRC (1994). Diets were formulated by linear formulation method using WinFeed 2.8 (WinFeed Ltd., Cambridge, UK). The nutrient specifications were lower than the NRC (1994) requirements for broiler starter diets (for 0 to 21 d). The digestible AA met or exceeded the ideal AA ratio, as suggested by Baker and Han (1994), in which digestible Lys was considered as reference AA to calculate other indispensable AA. Each diet was converted into 2 portions. One portion was mixed with vitamin and mineral premix, whereas other portion was mixed with vitamin and mineral premix plus enzyme at 50 mg/kg (Rovabio Excel AP, Adisseo Asia Pacific Pte Ltd., Singapore) of finished feed. Cane molasses and oil was added thereafter. The supplemental enzyme activities reported by the supplier were 22,000 visco units/g (equivalent to 1,400 units/g) for endo-1,4-ß xylanase (EC 3.2.1.8 [EC] ) and 2,000 units/g for endo-1,3(4)-ß glucanase (EC 3.2.1.6 [EC] ). One visco unit of endo-1,4-ß xylanase is defined as the amount of enzyme that hydrolyzes the substrate, reducing the viscosity of the standard wheat arabioxylan solution to give a change in relative fluidity of 1 (dimensionless unit)/min per milligram of enzyme, whereas 1 xylanase unit is defined as the release of oligomers from chromophore-bound xylan, which are not precipitable by ethanol, equivalent to an absorbance of 1.23 units at 590 nm. One glucanase unit of endo-1,3(4)-ß glucanase is defined as the release of oligomers from a chromophore-bound glucan, which are not precipitable by ethanol, equivalent to an absorbance of 0.820 units at 590 nm. Endo-1,4-ß xylanase activity was assayed by the method described by Baily et al. (1992), with 1% oat-split xylan as the substrate for enzyme activity at 60°C. Each of the experimental diets (total of 12 dietary combinations) were offered to 4 replicates in mash form, and data were collected until 14 d of age. Feed and water were at will throughout the experiment.

Statistical Analyses
The experimental design was completely randomized with factorial structure. All the statistical analyses were performed by Minitab 13.3 (Minitab Inc., State College, PA). Pen mean was an experimental unit. Effect of enzyme addition (with and without), SFM (20 and 30%), and digestible Lys (0.8, 0.9, and 1.0%) were statistically analyzed as 2 x 2 x 3 factorial design by the GLM method of ANOVA (Mead et al. 1993). The level of significance was 0.05, unless otherwise stated.

	RESULTS

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The analyzed nutrient composition of the experimental diets was in close agreement with the calculated analyses. The aflatoxin contents of diets ranged from 42 to 63 µg/kg. The analyzed enzyme activity was 39.07 µmol/min per milligram for xylanase. The BW gain (BWG) during 1 to 7 and 1 to 14 d of age are presented in Table 2. The ANOVA summary is shown in Table 3. The BWG during 1 to 14 d of age was not influenced either by enzyme or level of SFM and increased linearly with digestible Lys contents of the diets. No significant effect of enzyme was observed at any age for BWG. The BWG for 0.8 and 0.9 % of digestible Lys were comparable during 1 to 7 d of age, whereas difference between these 2 levels was remarkable during 1 to 14 d of age. No significant difference of any other interaction was observed on BWG. Feed intake tended to decrease with the enzyme addition. The FI was not statistically significant either by digestible Lys or SFM at any stage. The digestible Lys requirement during the first week was lower compared with second week.

	DISCUSSION

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Addition of 20 and 30% of SFM in the experimental diets resulted in increases in dietary CF (Table 1). The results of the present study showed nonsignificant effects of adding 20 or 30% SFM on BWG, FI, feed:gain, or mortality. Enzyme addition failed to show any significant effect on overall performance of the bird. The depression with enzyme addition was particular at 20% of SFM in the diet (Table 2). The results of the present study are in line with those of Leeson et al. (1987), who replaced SFM to 100% of SBM and reported no adverse effect on performance and energy utilization when Lys was added as the limiting AA. Villamide and San Juan (1998) suggested that depression caused by the high inclusion of dietary SFM is due to the difference in digestibility values for AA, which can be fixed if diet is formulated from true digestible AA. The results of the present study disagree with the findings of Swain et al. (1996), who reported an improvement in performance in high-CF sunflower cake with a multienzyme addition. The difference may be due to the different enzyme combination used in their study. Kocher et al. (2000) reported an improvement in the nutrient digestibility due to enzyme addition at high inclusion of SFM. They, however, did not observe any improvement in the live performance of the birds. Attia et al. (2003) showed no effect of commercial enzyme preparation Optizyme (Optivite, Retford, Nottinghamshire, UK) in dehulled SFM and reported no effect of SFM at 5, 10, or 15% on mortality. Cowan et al. (1999) reported an improvement in performance due to pectinase addition in SFM-based diets in female broilers. They reported a significant effect of pectinase at low- or medium-Lys diets and no difference in high-Lys diets. However, in the present study, no significant effect of enzyme addition was observed, even at very low digestible Lys (i.e., 0.80%) diets.

A linear (P 0.001) effect of digestible Lys was observed for feed:gain during 1 to 14 d of age. The results showed that 0.8 or 0.9% digestible Lys was below the birds’ requirements, and extra benefit can be taken by increasing the digestible Lys of the diet. The results are in close agreement with those reported by Knowles and Southern (1998), who estimated 1.0 and 1.1% digestible Lys for maximum daily BWG and feed:gain, respectively. The NRC (1994) lists a requirement of 1.1% Lys for broilers during 0 to 21 d of age (0.97% digestible Lys, assuming 88% digestibility in a corn-soy diet). The digestible Lys requirements were different at 2 different ages for average daily gain in the present investigation (data not shown). During first week posthatching, a level of 0.8% digestible Lys was sufficient for BWG, whereas it was 1.0% for 1 to 14 d. The low digestible Lys requirement during first week posthatching may be due to the presence of endogenous yolk, which contributes a greater part of the nutrients during the first week posthatching (Noy and Sklan, 1999). As the bird’s age increases, the yolk no longer contributes Lys, and digestible Lys requirement increases. Moreover, the endogenous proteolytic secretions during the first week posthatching are not great enough to fully utilize the high-digestible Lys (Krogdahl and Sell, 1989). The addition of an enzyme cocktail failed to show any significant effect during the first week that was otherwise expected. A greater dose or a different enzyme combination may be tried to boost up the response to high-digestible Lys for optimum performance in young birds. However, for feed:gain a level of 1.0% digestible Lys was observed best at both stages. Han and Baker (1991) reported that the digestible Lys requirement of 0- to 3-wk-old chicks was 1.01% for maximum BWG and FI and 1.21% for maximum feed efficiency. Also, total Lys requirements of 1.15% (1.02% digestible Lys) and 1.26% (1.12% digestible Lys) have been reported for BWG and feed efficiency, respectively (Baker and Han, 1994).

The present study demonstrated a linear effect of digestible Lys for both BWG and feed:gain. Similarly, Baker et al. (2002) observed a digestible Lys requirement of 0.97 and 1.02% for maximum BWG and feed efficiency, respectively. The study, however, was conducted on purified diets and cannot be applied as it is on practical commercial diets due to greater variation in the digestibility values of different feed ingredients and some positive or negative associative effects. Moreover, they used a graded supplementation technique for estimation of digestible Lys requirements. The limitation of the technique is that at high levels of AA in question, second-limiting AA becomes first-limiting AA, whereas in the present study, all of the AA were increased with the increasing level of digestible Lys. The reason for high-digestible Lys requirements in the present study may also be due to low CP and ME contents of the diets, and it seems that increasing digestible Lys may be beneficial in low-nutrient density diets.

In conclusion, SFM up to 30% of the diet has no adverse effect on the performance and livability of broiler chicks during 2 wk posthatching. A xylanase and glucanase combination failed to show any remarkable improvement in the performance of young chicks. The digestible Lys of the diet should not be less than 1.0% for young broilers.

	ACKNOWLEDGMENTS

 
The study was funded by the Higher Education Commission of Pakistan under the title "Merit Scholarship for PhD Studies in Science and Technology". The material support was provided by Research and Development Farms, Sadiq Brothers Poultry, Islamabad, Pakistan. We thank M. Aslam Mirza for valuable suggestions for this manuscript.

Received for publication January 17, 2006. Accepted for publication June 25, 2006.

	REFERENCES

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
Attia, Y. A., M. A. Al-Harthi, and A. A. El-Deek. 2003. Nutritive value of undehulled sunflower meal as affected by multienzyme supplementation to broiler diets. Arch. Geflü gelk. 67:97–106.

Baily, M. J., P. Biely, and K. Poutanen. 1992. Interlaboratory testing of methods for assay of xylanase activity. J. Biotechnol. 23:257–270.

Baker, D. H., A. B. Batal, T. M. Parr, N. R. Augspurger, and C. M. Parsons. 2002. Ideal ratio (relative to lysine) of tryptophan, threonine, isoleucine, and valine for chicks during the second and third week posthatch. Poult. Sci. 81:485–494.[Abstract/Free Full Text]

Baker, D. H., and Y. Han. 1994. Ideal amino acid profile for chicks during the first three weeks posthatching. Poult. Sci. 73:1441–1447.[ISI][Medline]

Cowan, W. D., D. R. Pettersson, and P. B. Rasmussen. 1999. The influence of multi-component pectinase enzymes on energy and amino acid availability in vegetable proteins. Pages 85–88 in Proc. Aust. Poult. Sci. Symp. Vol. 11. University of Sydney, Australia.

Halvey, O., A. Goyra, M. Barak, A. Uni, and D. Sklan. 2000. Early starvation affects satellite cell proliferation and muscle growth in the chicks. J. Nutr. 130:858–864.[Abstract/Free Full Text]

Han, Y., and D. H. Baker. 1991. Lysine requirements of fast-and slow-growing broiler chicks. Poult. Sci. 70:2108–2114.[ISI][Medline]

Knowles, T. A., and L. L. Southern. 1998. The lysine requirement and ratio of total sulfur amino acids to lysine for chicks fed adequate or inadequate lysine. Poult. Sci. 77:564–569.[Abstract/Free Full Text]

Kocher, A., M. Choct, M. D. Porter, and J. Broz. 2000. The effects of enzyme addition to broiler diets containing high concentrations of canola or sunflower meal. Poult. Sci. 79:1767–1774.[Abstract/Free Full Text]

Krogdahl, A., and J. L. Sell. 1989. Influence of age on lipase, amylase, and protease activities in pancreatic tissue and intestinal contents of young turkeys. Poult. Sci. 68:1561–1568.[ISI][Medline]

Leeson, S., J. O. Atteh, and J. D. Summers. 1987. The replacement value of canola meal to soybean meal in poultry diets. Can. J. Anim. Sci. 67:151–158.

Leeson, S., and J. D. Summers. 2001. Nutrition of the Chicken. 4th ed. Univ. Books, Guleph, Ontario, Canada.

Mead, R., R. N. Curnow, and A. M. Hasted. 1993. Statistical Methods in Agriculture and Experimental Biology. 2nd ed. Chapman and Hall, London, UK.

Mushtaq, T., M. Sarwar, H. Nawaz, M. A. Mirza, and T. Ahmad. 2005. Effect and interactions of dietary sodium and chloride on broiler starter performance (hatching to twenty-eight days of age) under subtropical summer conditions. Poult. Sci. 84:1716–1722.[Abstract/Free Full Text]

National Research Council. 1994. Nutrient Requirements of Poultry. 9th rev. ed. Natl. Acad. Press, Washington, DC.

Nitsan, Z., G. Ben-Avraham, Z. Zoref, and I. Nir. 1991. Growth and development of the digestive organs and some enzymes in broiler chicks after hatching. Br. Poult. Sci. 32:515–523.[ISI][Medline]

Noy, Y., and D. Sklan. 1995. Digestion and absorption in the young chick. Poult. Sci. 74:366–373.[ISI][Medline]

Noy, Y., and D. Sklan. 1999. Energy utilization in newly hatched chicks. Poult. Sci. 78:1750–1756.[Abstract/Free Full Text]

Ravindran, V., and R. Blair. 1992. Feed resources for poultry production in Asia and the Pacific. II. Plant protein sources. World’s Poult. Sci. J. 48:205–231.

Rosebrough, W., A. D. Mitchell, and J. P. McMurty. 1996. Dietary crude protein changes rapidly alter metabolism and plasma insulin-like growth factor 1 concentration in broiler chickens. J. Nutr. 126:2888–2898.[Abstract/Free Full Text]

Sklan, D. 2001. Development of the digestive system of poultry. World’s Poult. Sci. J. 57:415–428.[ISI]

Sklan, D., and Y. Noy. 2003. Crude protein and essential amino acid requirements in chicks during the first week posthatch. Br. Poult. Sci. 44:266–274.[ISI][Medline]

Swain, B. K., T. S. Johri, A. K. Shrivastav, and S. Majumdar. 1996. Performance of broilers fed on high or low fibre diets supplemented with digestive enzymes. J. Appl. Anim. Res. 10:95–102.

Villamide, M. J., and L. D. San Juan. 1998. Effect of chemical composition of sunflower seed meal on its true metabolizable energy and amino acid digestibility. Poult. Sci. 77:1884–1892.[Abstract/Free Full Text]

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