J. Appl. Poult. Res.
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J APPL POULT RES 2008. 17:202-210. doi:10.3382/japr.2007-00038
© 2008 Poultry Science Association
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Research Reports

The Effects of a Natural Antibiotic Alternative and a Natural Growth Promoter Feed Additive on Broiler Performance and Carcass Quality1

N. P. Buchanan*, J. M. Hott*, S. E. Cutlip*, A. L. Rack*, A. Asamer{dagger} and J. S. Moritz*,2

* Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV 26506; and {dagger} Delacon Biotechnik, Steyregg, Austria

2 Corresponding author: Joe.Moritz{at}mail.wvu.edu


   SUMMARY
TOP
 SUMMARY
DESCRIPTION OF PROBLEM
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSIONS AND APPLICATIONS
 REFERENCES AND NOTES
 
The use of subtherapeutic levels of antibiotics in poultry feed improves performance and morbidity in broiler chickens. However, consumer pressure related to the potential development of antibiotic-resistant bacteria has resulted in the development of nonantibiotic feed additives that may also improve broiler performance. Essential oils, organic acids, and phytogenic compounds enhance production of gastric secretions, stimulate blood circulation, and reduce levels of pathogenic bacteria. The objective of the current study was to assess the use of Biostrong 505+ and Biostrong 510 as natural growth promoters in broiler chickens. Assessment was based on the performance and carcass quality of broilers fed either a maximum-yield or a least-cost commercial broiler diet. The maximum-yield diet improved broiler performance and carcass quality. Biostrong 505+ can be used to improve feed conversion and breast yield when incorporated into diets devoid of antibiotics. This improvement in feed conversion and breast yield was accentuated when Biostrong 505+ was used in conjunction with a maximum-yield diet. Biostrong 510 improved feed conversion when used in poultry diets containing antibiotics.

Key Words: broiler production • phytogenic feed additive • antibiotic alternative


   DESCRIPTION OF PROBLEM
TOP
 SUMMARY
 DESCRIPTION OF PROBLEM
MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSIONS AND APPLICATIONS
 REFERENCES AND NOTES
 
In the 1950s, the US Food and Drug Administration approved the use of subtherapeutic levels of antibiotics in animal feeds. Antibiotics are fed to production animals to prevent disease and promote growth [1]. However, the use of antibiotics in animal feeds has been linked to antibiotic-resistant bacteria [2, 3]. Consequently, many countries have banned the use of subtherapeutic levels of antibiotics in production animal rations. The United Kingdom banned the use of penicillin and tetracycline for growth promotion in the 1970s [4]. The United States banned the use of enrofloxacin in 2005 [5]. Sweden and Denmark banned all growth-promoting antibiotics in 1986 and 1999, respectively [4]. As a result of the ban, weanling pigs in Denmark were reported to encounter severe health problems requiring treatment with antibiotics at levels exceeding those required for subtherapeutic use [6]. On the basis of these data, a US ban on growth-promoting antibiotics in hog feed was estimated to increase disease-treatment costs by $4.50/pig per year or $700 million over a 10-yr period [6]. The Council for Agricultural Science and Technology estimates that a ban on subtherapeutic antibiotics in all livestock feed would result in aggregate losses of $1 million to $28 billion over a 5-yr period [7]. Moreover, broiler producers may lose up to $12 billion over a 5-yr period if no substitutes are used in lieu of antimicrobial drugs [8]. To thwart a potential economic hardship and alleviate problems associated with antibiotic resistance, phytogenic feed additives have been developed as alternatives to antibiotics.

A variety of substances are used in conjunction with, or as alternatives to, antibiotics in poultry diets. Probiotics, prebiotics, organic acids, and plant extracts have all shown promising results for use in organic poultry production [9]. These alternatives are necessary because federal regulations prohibit the use of conventional antibiotics and growth promoters in organic production [10]. Formic, acetic, and propionic acids reduce the prevalence of Salmonella and Campylobacter bacteria found in the intestines of broilers [11, 12]. Moreover, Clostridium perfringens, Salmonella Typhimurium, and Escherichia coli may be controlled through the use of essential oils derived from plant extracts [13].

The phytogenic feed additive Biostrong 505+ [14] was developed for poultry and is marketed as a product that will improve the stability of intestinal microflora [15]. Biostrong 505+ contains a proprietary blend of plant extracts (microencapsulated essential oils, bitter substances, pungent substances) and an acid complex. Another phytogenic feed additive, Biostrong 510 [14], is marketed to be used in conjunction with antibiotics to optimize performance in poultry by enhancing the retention of essential nutrients and minerals [16]. Biostrong 510 contains a proprietary blend of plant extracts such as essential oils, bitter substances, pungent substances, and saponins.

The essential oils found in Biostrong 5059+ and Biostrong 510 occur naturally under the surface of plants for protection against fungi, bacteria, and viruses [15, 16]. These essential oils stimulate the intestinal lining and digestive glands, resulting in an increase in the production of endogenous enzymes [16]. Bitter substances are found in herbs and stimulate the secretion of gastric juices [15, 16]. The pungent substances are found in plants such as paprika, garlic, and onion and are purported to function by increasing blood circulation, leading to faster detoxification of the whole metabolism [15].

The objective of this study was to assess the use of Biostrong 505+ and Biostrong 510 as natural growth promoters in 2 different commercial broiler diet formulations. Assessment was based on the performance and carcass quality of broiler chickens.


   MATERIALS AND METHODS
TOP
 SUMMARY
 DESCRIPTION OF PROBLEM
 MATERIALS AND METHODS
RESULTS AND DISCUSSION
 CONCLUSIONS AND APPLICATIONS
 REFERENCES AND NOTES
 
A diet formulation (maximum yield or least cost) x phytogenic feed additive (additive or no additive) factorial design was used to provide a total of 4 dietary treatments for the Biostrong 505+ experiment and 4 additional treatments for the Biostrong 510 experiment: Max/505+, Max/ No505+, Least/505+, Least/No505+, Max/510, Max/No510, Least/510, and Least/No510. The Biostrong 505+ and the Biostrong 510 experiments were conducted during the same time period. However, each experiment was conducted in different floor-pen rooms and statistical analysis was performed separately. The maximum-yield and least-cost diets were formulated based on Cobb-Vantress Inc. [17] recommendations (Table 1Go). When applicable, a premix containing Biostrong 505+ was included in the diet at 0.05% (0.025% active 505+) and a premix containing Biostrong 510 was included in the diet at 0.05% (0.015% active 510). Diets formulated for the Biostrong 505+ experiment excluded antibiotics. Diets formulated for the Biostrong 510 experiment contained the antibiotic bacitracin methylene disalicylate [18] included at 0.05% of the total ration.


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  		Table 1. Diet formulations
 
Three-phase feeding (starter, grower, finisher) was used (Table 1Go). All 8 diets were conditioned by using a short-term conditioner [0.31x 1.30 m (1.02 x 4.25 ft), 10 s retention time] set at a constant temperature of 82.2°C (180°F) and a saturated steam pressure of 262 kPa (38 psi at guage). Pellets were formed by using a Master Model California Pellet Mill with a 4.76x 44.96 mm (3/16 x 1.77 in.) die. Starter diets were crumbled and fed from 0 to 18 d. Grower and finisher diets were fed in pelleted form from 19 to 30 d and 31 to 40 d, respectively.

A total of 1,344 Cobb 500 broilers [17] of mixed sex were obtained from a commercial hatchery at hatch. Broilers were randomly allotted to 1 of 64 floor pens [0.69 x 2.44 m (2.26 x 8.00 ft)] located in 2 rooms joined by a woven-wire barrier that allowed heat and ventilation to move freely between the rooms. Rooms were located in a cross-ventilated negative-pressure house with forced-air brooders. The first room contained the Biostrong 505+ treatments and the second room contained the Biostrong 510 treatments. Broilers were provided with feed and water, supplied through Kuhl [19] feed pans adapted to hoppers and Ziggity [20] nipple drinkers, for ad libitum consumption. Temperature of the rooms was maintained at 32.2°C (90.0°F) and decreased to 21.1°C (70.0°F) during the 0- to 3-wk period. For the 3- to 6-wk period, the temperature remained at 21.1°C (70.0°F).

The Biostrong 505+ and Biostrong 510 experiments were conducted simultaneously in separate rooms. Each room contained 8 blocks, and each block was composed of a group of 4 pens. Every treatment within an experiment (Biostrong 505+ or Biostrong 510 experiment) was represented in each block in the respective room. Broilers were placed at a stocking density of 21 birds/pen [0.065 m2/bird (0.70 ft2/bird)]. All broilers were reared on built-up litter obtained from a commercial broiler house and transported to the West Virginia University poultry farm.

Live weight gain (LWG), feed intake, feed conversion (FC), and percentage mortality (Mort) were determined from 0 to 18 d, 19 to 30 d, 31 to 40 d, and 0 to 40 d. Foot pad lesion (FPL) scores were determined on d 40 by using the method outlined by Dawkins et al. [21]. Litter samples were taken from each pen, mixed within treatment, and analyzed for DM [22] and microbial content [23] on d 0 and 40.

On d 40, two male broilers per pen, ±100 g of the mean pen weight for males, were processed at the West Virginia University pilot processing plant. Carcass weight (CW), bone-in breast yield (BY), and fat pad yield (FPY) data were obtained. All animals were reared according to protocols established by the West Virginia University Animal Care and Use Committee.

Statistical Analysis
Statistical analyses were performed separately for the Biostrong 505+ and the Biostrong 510 experiments. The GLM ANOVA procedure of SAS Institute [24] was used to explore significance among treatment means for the Biostrong 505+ group and Biostrong 510 group. A male-to-female ratio was used as a covariate for performance analysis. Significant effects were further explored by using Fisher’s LSD test. A diet formulation x phytogenic feed additive randomized complete block factorial analysis was used to explore the main effects and interactions for each measured variable. Means were considered significantly different at P < 0.05.


   RESULTS AND DISCUSSION
TOP
 SUMMARY
 DESCRIPTION OF PROBLEM
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
CONCLUSIONS AND APPLICATIONS
 REFERENCES AND NOTES
 
Litter Samples Analyses
The DM and microbial content of litter samples obtained on d 0 and 40 are described in Table 2Go. Litter analyses are presented as supporting data and to show that a potential immune challenge was present.


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  		Table 2. Litter DM and microbial content (d 0 and 40)
 
Biostrong 505+
Performance data for the 0- to 18-d, 19- to 30-d, and 31- to 40-d periods were analyzed. Only performance data for the 0- to 40-d period is discussed (Table 3Go). To negate the effects of varying LWG, the BY and FPY are reported as a percentage of CW.


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  		Table 3. Performance and carcass quality data for 0- to 40-d broiler chickens in the Biostrong 505+ experiment1
 
Broilers fed Max/505+ had lower FC (P < 0.05) and higher BY (P < 0.05) compared with broilers fed the other treatments. Antibiotic alternatives have been shown to decrease the prevalence of pathogenic gut microflora [11–13]. The ingredients comprising Biostrong 505+ may decrease pathogenic gut microflora. For example, essential oils, bitter substances, and organic acids, all components of Biostrong 505+, have been shown to reduce the prevalence of pathogenic bacteria such as Clostridium perfringens, E. coli, and Salmonella Typhimurium [13, 25, 26]. In return, stability of the residual gut microflora may improve and the metabolic costs associated with immune function may be reduced. As a result, more energy from the maximum-yield diet may have been available for muscle accretion. Stanley et al. [27] reported a decrease in intestinal coliform count and a subsequent increase in BW when broilers were fed an antibiotic alternative (yeast culture residue) compared with broilers fed a control diet. Additionally, Leeson et al. [26] reported increased breast meat weights for broilers fed 0.2% butyric acid compared with broilers fed a control diet. Biostrong 505+, when used in conjunction with a maximum-yield diet, resulted in the lowest FC (P < 0.05) and the highest BY (P < 0.05).

A diet formulation effect was observed for LWG (P = 0.0034), FC (P = 0.0001), CW (P = 0.0001), BY (P = 0.0301), and FPY (P = 0.0127). Significant effects associated with LWG and FC were consistent for the duration of the experiment. The maximum-yield diets improved FC (P < 0.05) for all experimental periods. Improvement in LWG was observed for the 19- to 30- d period (P = 0.0545) and the 31- to 40-d period (P = 0.0047; data not presented). Feeding the maximum-yield diet resulted in increased performance and improved carcass quality compared with the least-cost diet. By design, the maximum-yield diet had higher amino acid and CP levels.

The incorporation of Biostrong 505+ into either formulation resulted in improved FC (P = 0.0109) and BY (P = 0.0577). Parks et al. [28] reported similar improvements in FC when an antibiotic alternative containing mannanoligosaccharides was fed to male turkeys. Feed intake, Mort, and FPL were not affected by diet formulation or phytogenic feed additive inclusion (P > 0.05).

Biostrong 510
Performance data for the 0- to 18-d, 19- to 30-d, and 31- to 40-d periods were analyzed. Only performance data for the 0- to 40-d period is discussed (Table 4Go). To negate the effects of varying LWG, the BY and FPY are reported as a percentage of CW.


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  		Table 4. Performance and carcass quality data for 0 to 40 d broiler chickens in the Biostrong 510 experiment1
 
Feeding Least/No510 reduced the incidence of FPL compared with all other dietary treatments (P < 0.05). A diet formulation (P = 0.0042) effect and phytogenic feed additive (P = 0.0259) effect were observed for FPL. Feeding least-cost diets resulted in a reduced incidence of FPL. Litter samples from pens containing broilers fed maximum-yield diets contained approximately 9.50% more moisture than pens containing broilers fed least-cost diets (Table 2Go). The exclusion of Biostrong 510 resulted in a reduced incidence of FPL. This finding was unexpected. Biostrong 510 contains saponins that have been reported to reduce gaseous ammonia and increases animal welfare [29, 30]. However, litter samples from pens containing broilers fed Biostrong 510 contained 5.25% more moisture than did litter samples from pens containing broilers fed no Biostrong 510 (Table 2Go). Perhaps this increase in moisture negated the positive effects associated with saponins.

Carcass weight was larger for broilers fed Max/No510 compared with all other broilers (P < 0.05; Table 4Go). This finding was unexpected, given that no differences in LWG were observed (P > 0.05). Perhaps differences in CW and LWG are a result of differences in the birds that were selected to be processed. For the LWG analysis, straight-run broilers were used. A male-to-female covariate was used to control variation in the numbers of males and females among pens. However, CW, BY, and FPY were measured only in males.

The inclusion of Biostrong 510 resulted in decreased CW (P = 0.0001; Table 4Go). However, the inclusion of Biostrong 510 did not affect LWG (P = 0.8646). Perhaps these conflicting results are due to the aforementioned variation in the sex of broilers used for LWG and CW analyses. Moreover, the conflicting CW data may be explained by fluctuations in the effect of Biostrong 510 on LWG throughout the experiment. In the 0- to 18-d period, the inclusion of Biostrong 510 in either diet formulation resulted in decreased LWG (P = 0.0570). However, in the 19- to 30-d period, LWG improved only when Biostrong 510 was included in the maximum-yield diet (P = 0.0279; data not presented). The inclusion of Biostrong 510 did not affect LWG for the 30- to 40-d period (P = 0.6482).

The maximum-yield diet improved CW (P = 0.0011), BY (P = 0.0003), and FPY (P = 0.0083) compared with the least-cost diet (Table 4Go). Furthermore, the inclusion of Biostrong 510 in either formulation improved FC (P = 0.0438). Essential oils from cinnamon, pepper, and oregano have been shown to improve digestibility in chickens receiving supplemented diets [25]. Additionally, saponins have been reported to increase the absorption of nutrients [31]. The essential oils and saponins present in Biostrong 510 may have led to increased digestibility of nutrients.

Use of a maximum-yield diet improved broiler performance and carcass quality. Moreover, Biostrong 510 can be used in conjunction with antibiotics to improve FC. Live weight gain, feed intake, and Mort were not affected by the diet formulation or phytogenic feed additive (P > 0.05).


   CONCLUSIONS AND APPLICATIONS
TOP
 SUMMARY
 DESCRIPTION OF PROBLEM
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSIONS AND APPLICATIONS
REFERENCES AND NOTES
 

  1. A commercial maximum-yield diet improved broiler performance and carcass quality compared with a least-cost diet.
  2. Biostrong 505+ can be used to improve FC and BY when incorporated into diets devoid of antibiotics. This improvement in FC and BY was accentuated when Biostrong 505+ was used in conjunction with a maximum-yield diet.
  3. Biostrong 510 improved broiler FC when used in poultry diets containing antibiotics. However, the prevalence of FPL was increased when Biostrong 510 was used in these poultry rations.


   FOOTNOTES
 
1 The use of the trade names Biostrong 505+ and Biostrong 510 in this publication does not imply endorsement of the products mentioned or criticism of similar products not mentioned. Back


   REFERENCES AND NOTES
TOP
 SUMMARY
 DESCRIPTION OF PROBLEM
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSIONS AND APPLICATIONS
 REFERENCES AND NOTES
 

  1. Centers for Disease Control and Prevention, National Antimicrobial Resistance Monitoring System. 2005. National Antimicrobial Resistance Monitoring System (NARMS) frequently asked questions (FAQ) about antibiotic resistance—Why are antibiotics used in food-producing animals? http://www.cdc.gov/narms/faq_pages/7.htm Accessed March 2007.
  2. Holmberg, S. D., M. T. Osterholm, K. A. Senger, and M. L. Cohen. 1984. Drug-resistant Salmonella from animals fed antimicrobials. N. Engl. J. Med. 311:617–622.[Abstract]
  3. Glynn, M. K., C. Bopp, W. Dewitt, P. Dabney, M. Mokhtar, and F. J. Angulo. 1998. Emergence of multidrug-resistant Salmonella enterica serotype Typhimurium DT104 infections in the United States. N. Engl. J. Med. 338:1333–1339.[Abstract/Free Full Text]
  4. Food Marketing Institute. 2006. Low-level use of antibiotics in livestock and poultry. http://www.fmi.org/media/bg/antibiotics.pdf Accessed Aug. 2007.
  5. United States Food and Drug Administration, Department of Health and Human Services. 2005. Withdraw of approval of the new animal drug application for enrofloxacin in poultry. Docket No. 2000N-1571. United States Food and Drug Admin., Dept. Health and Human Serv., Washington, DC.
  6. Hayes, D. J., and H. H. Jenson. 2003. Lessons from the Danish ban on feed-grade antibiotics. Pages 1–12 in Briefing Paper 03-BP 41. Center for Agric. Rural Dev., Iowa State Univ., Ames.
  7. Council for Agricultural Science and Technology. 1981. Antibiotics in animal feeds. Report No. 88. Counc. Agric. Sci. Technol., Ames, IA.
  8. Matthews, K. H. 2001. Antimicrobial drug use and veterinary costs in U.S. livestock production. Agric. Inf. Bull. 766. US Dept. Agric., Econ. Res. Serv., Market and Trade Econ. Div. and Resour. Econ. Div., Washington, DC.
  9. Griggs, J. P., and J. P. Jacob. 2005. Alternatives to antibiotics in organic poultry production. J. Appl. Poult. Res. 14:750–756.[Abstract/Free Full Text]
  10. Agricultural Marketing Service. 2003. National Organic Program: Amendments to the National List of Allowed and Prohibited Substances. Final Rule. 7CFR Part 205. Fed. Regist. 68:61987–61993.
  11. Hinton, M., and A. H. Linton. 1988. Control of Salmonella infections in broiler chickens by the acid treatment of their feed. Vet. Rec. 123:416–421.[Abstract]
  12. Chaveerach, P., L. J. A. Lipman, and F. van Knapen. 2004. Antagonistic activities of several bacteria on in vitro growth of 10 strains of Campylobacter jejuni/coli. Int. J. Food Microbiol. 90:43–50.[CrossRef][Web of Science][Medline]
  13. Mitsch, P., K. Zitterl-Eglseer, B. Kohler, C. Gabler, R. Losa, and I. Zimpernik. 2004. The effect of two different blends of essential oil components on the proliferation of Clostridium perfringens in the intestines of broiler chickens. Poult. Sci. 83:669–675.[Abstract/Free Full Text]
  14. Biostrong 505+ and Biostrong 510, Delacon Biotechnik, Steyregg, Austria.
  15. Delacon Phytogenic Feed Additives. 2004. Biostrong 505—The preventative solution for profitable poultry fattening. Delacon Biotechnik, Steyregg, Austria.
  16. Delacon Phytogenic Feed Additives. 2004. Biostrong 510—The performizer for improved nutrient retention. Delacon Biotechnik, Steyregg, Austria.
  17. Cobb-Vantress Inc., Siloam Springs, AR.
  18. Bacitracin methylene disalicylate, 50 g/ton inclusion; Alpharma Inc., Fort Lee, NJ.
  19. Feed pan and hopper; Kuhl Corporation, Flemington, NJ.
  20. Water system; Ziggity Systems Inc., Middlebury, IN.
  21. Dawkins, M. S., C. A. Donnelly, and T. A. Jones. 2004. Chicken welfare is influenced more by housing conditions than by stocking density. Nature 427:342–344.[CrossRef][Medline]
  22. AOAC. 2002. Official Methods of Analysis. 17th ed. AOAC Int., Gaithersburg, MD.
  23. Great Lakes Scientific Inc., Stevensville, MI.
  24. SAS Institute. 2000. The SAS System for Windows 2000. Release 8.1. SAS Inst. Inc., Cary, NC.
  25. Hernández, F., J. Madrid, V. Garcia, J. Orengo, and M. D. Megías. 2004. Influence of two plant extracts on broilers performance, digestibility, and digestive organ size. Poult. Sci. 83:169–174.[Abstract/Free Full Text]
  26. Leeson, S., H. Namkung, A. Antongiovanni, and E. H. Lee. 2005. Effect of butyric acid on the performance and carcass yield of broiler chickens. Poult. Sci. 84:1418–1422.[Abstract/Free Full Text]
  27. Stanley, V. G., C. Gray, M. Daley, W. F. Krueger, and A. E. Sefton. 2004. An alternative to antibiotic-based drugs in feed for enhancing performance of broilers grown on Eimeria spp.-infected litter. Poult. Sci. 83:39–44.[Abstract/Free Full Text]
  28. Parks, C. W., J. L. Grimes, P. R. Ferket, and A. S. Fairchild. 2001. The effect of mannanoligosaccharides, bambermycins, and virginiamycin on performance of Large White male market turkeys. Poult. Sci. 80:718–723.[Abstract/Free Full Text]
  29. Westendarp, H. 2005. Saponins in nutrition of swine, poultry, and ruminants. Dtsch. Tierarztl. Wochenschr. 112:65–70.[Medline]
  30. Nazeer, M. S., T. N. Pasha, S. Abbas, and Z. Ali. 2002. Effect of Yucca saponin on urease activity and development of ascites in broiler chickens. Int. J. Poult. Sci. 1:174–178.
  31. Walker, R. D. 1993. The effects of a urease inhibitor on ascites mortality. Poult. Sci. 72(Suppl. 1):4. (Abstr.)




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