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Evaluation of Zeolites in the Diet of Broiler Chickens1
Evaluation of Zeolites in the Diet of Broiler Chickens1 P. W. WALDROUP, G. K. SPENCER, and N. K. SMITH Department of Animal Sciences, University of Arkansas, Fayetteville, Arkansas 72701 (Received for publication October 4, 1983)
1984 Poultry Science 63:1833-1836 INTRODUCTION
Zeolites, minerals of volcanic origin, are crystalline, hydrated aluminosilicates of alkali and alkaline earth cations, having an infinite, three-dimensional structure (Mumpton and Fishman, 1977). Hatieganu et al. (1979) reported that the addition of zeolites in the feed of broilers at between 5 and 9% improved growth 9 to 12% and feed utilization by 12%. Willis et al. (1982) reported that addition of certain zeolites to broiler rations at 21 days gave significant improvements in body weight gains and feed efficiency. Because previous studies from this station (Waldroup and Ragland, 1977; Sellers et al, 1980) failed to show response from the addition of different types of clays and inert fillers to broiler diets, studies were conducted to examine the possible response to addition of zeolites to the diet of broiler chickens. MATERIALS AND METHODS
Two experiments were conducted to determine the effects of zeolites on broiler chickens using diets considered to be adequate in all known nutrients. Diets used in this study were formulated to meet or exceed nutrient requirements suggested by the National Research Council (NRC, 1977) for the appropriate age. Diets contained yellow corn, soybean meal, a commercial animal-vegetable fat blend,
1 Published with the approval of the Director, Arkansas Agricultural Experiment Station.
and meat and bone meal as intact sources of energy and protein. Diets were fortified with vitamin and trace mineral mixes that were considered to be nutritionally adequate. Ingredient composition values reported by the NRC (1977) were used in formulation. The composition of diets used in these experiments is given in Table 1. In the first experiment, all diets were formulated to contain 3.20 kcal/g metabolizable energy, the base energy value used in establishing nutrient requirements by the NRC. In the second experiment, all chicks were fed to 21 days of age using the same formulation as used in Experiment 1. Three diet series were then used from 21 days to the conclusion of the study. These diets contained 1.25, 3.75, and 6.25% added fat in Series A, B, and C, respectively. Diets were formulated to optimum energy density with amino acids, calcium, and inorganic phosphorus maintained in ratio with energy. All diets contained monensin (99 mg/kg) from 1 to 42 days and zinc bacitracin (55 mg/kg) throughout the study. In both experiments, all chicks were fed a common basal diet from 1 to 21 days of age with test diets containing zeolite fed for the remainder of the study. Sexed chicks of a commercial broiler strain were obtained from a local hatchery and were randomly allocated into pens. In the first experiment there were 35 chicks of each sex per pen while in the second trial there were 25 chicks of each sex per pen. The pens were 5.2 m 2 and contained two hanging tube-type feeders and an automatic waterer. Wood shavings were used as litter over concrete floors.
1833
Downloaded from http://ps.oxfordjournals.org/ at Serials Section, Dixson Library on June 9, 2015
ABSTRACT Two experiments were conducted in which zeolites were added to broiler diets at the 1% level beginning at 21 days of age. In one study, diets with different energy levels were used to determine if an interaction existed between zeolite supplementation and nutrient density. No beneficial effects of zeolite supplementation on body weights were observed in either experiment. There were no statistically significant differences in feed utilization between diets with and without zeolites, and the numerical differences could be accounted for by the addition of 1% inert zeolite. (Key words, zeolites, broilers, nutrition)
3.07 19.22
18.00
100.00
19.86
3.18
100.00
3.11 17.53
20.51
3.32 18.70
3.22 18.11
100.00 100.00 100.00
100.00 3.28
.37 .10 .50 .01
.37 .10 .50 .01 .37 .10 .50 .00 .37 .10 .50 .08
.37 .10 .50 .07
.37 .10 .50 .06
1.43 2.01 1.42 1.95
62.62 27.34 6.25
1.42 1.83
1.44 1.94
1.42 1.83
66.62 25.28 3.75
C
0
7.31 23.22 1.25
B
42 to 49 days
0
A
Experiment 2
0
1.39 1.76
57.44 31.88 6.25 0
C
0
62.28 29.68 3.75
B
0
67.10 27.47 1.25
A
3.20
100.00
.49 .72 .40 .10 .50 .03
72.10 18.79 1.87 5.00
42 to 47 days
Supplied per kilogram of diet: 100 mg iron, 100 mg manganese, 100 mg zinc, 100 mg copper, 1 mg iodine.
20.00
100.00
100.00
23.00
.51 .64 .40 .10 .50 .10
.52 .51 .40 .10 .50 .23
3.20
65.83 24.04 2.88 5.00
56.38 31.95 4.41 5.00
3.20
21 to 42 days
Oto 21 days
21 to 42 days
Supplied per kilogram of diet: 6600 IU vitamin A, 2200 IU vitamin D 3 , 6.6 IU vitamim E, 3.3 mg menadione, 5.5 mg riboflavin, 33 mg niacin, 8.8 mg pantothenic acid, 495 mg choline, 1.1 mg thiamin, 1.1 mg pyridoxine, .0099 mg vitamin B 1 2 , .11 mg biotin, .66 mg folacin, 1 mg selenium, 62.5 mg ethoxyquin.
2
1
Calculated analysis Metabolizable energy, kcal/g Protein, %
Yellow corn Soybean meal Blended fats Meat and Bone meal Ground limestone Dicalcium phosphate Iodized salt Trace minerals 1 Vitamin premix 2 DL-Methionine Total
Ingredient
Experiment 1
TABLE 1. Composition of experimental diets (% of mixture)
om http://ps.oxfordjournals.org/ at Serials Section, Dixson Library on June 9, 2015
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ZEOLITES FOR BROILERS
1835
TABLE 2. Effects of zeolite supplementation on body weight gain and feed utilization by broilers (Experiment 1)
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In the first trial, beginning at 21 days of age, 16 pens of chicks were fed the unsupplemented control diets while an equal number were fed a diet in which 1 part of corn was replaced with 1 part of zeolite. In the second experiment, each of the three diet series was fed without zeolite supplement. In three additional groups, 1 part of zeolite was blended with 99 parts of each of the three test diets. Each of these six treatment groups was fed to eight pens of chickens. In both studies, all diets were fed free-choice in pellet from. Body weights and feed consumption were determined at 21, 43, and 47 days of age in the first experiment and at 21, 42, and 49 days in the second experiment. Feed efficiency data were corrected for the weight of birds that died during the study. The data were subjected to the analysis of variance using SAS release 82.2B (SAS Institute, 1982).
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RESULTS
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In the first experiment, the replacement of 1 part of corn in the diet by an equal amount of zeolite had no effect on body weight at 42 or 47 days of age (Table 2). For the period from 21 to 47 days, during which time zeolite was fed, there were no significant differences in feed utilization between the treatment groups. Chickens fed the diet with zeolite generally had slightly lower feed utilization than those fed the unsupplemented control diet; however, if corrected for the 1% inert zeolite, values for the two treatments were almost identical. Similar results were found in the second experiment (Table 3). At 21 days of age, during
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Downloaded from http://ps.oxfordjournals.org/ at Serials Section, Dixson Library on June 9, 2015
Grams gain/gram feed 1 to 21 days 1 to 42 days 1 to 47 days 21 to 42 days 42 to 47 days
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No zeolite
• * .
1836
WALDROUP ET AL.
ACKNOWLEDGMENTS The authors express their appreciation to the Occidental Minerals Corporation and to PhelpsDodge Zeolites for financial support of these trials.
REFERENCES Hatieganu, V., I. Puia, O. Popa, and G. Baltan, 1979. Utilizarea zeolitilor naturali in hrana animalelor (sinteza). [The use of natural zeolites in the feeding of animals (synthesis)] . Zootech. Med. Vet. 33:27-34. Mumpton, F. A., and P. H. Fishman, 1977. The application of natural zeolites in animal sciences and aquaculture. J. Anim. Sci. 45:1188—1203. National Research Council, 1977. Nutrient Requirements of Domestic Animals. 1. Nutrient Requirements of Poultry. Natl. Acad. Sci., Washington, DC. SAS Institute, Inc., 1982. SAS User's Guide: Statistics, 1982 ed. SAS Inst., Cary, NC. Sellers, R. S., G. C. Harris, Jr., and P. W. Waldroup, 1980. The effects of various dietary clays and fillers on the performance of broilers and laying hens. Poultry Sci. 59:1901-1906. Waldroup, Park W., and D. R. Ragland, 1977. Spent filter clay as a potential feed ingredient for broiler diets. Nutr. Rep. Int. 16:249-254. Willis, W. L., C. L. Quarles, D. J. Fagerberg, and J. V. Shutze, 1982. Evaluation of zeolites fed to male broiler chickens. Poultry Sci. 61:438—442.
Downloaded from http://ps.oxfordjournals.org/ at Serials Section, Dixson Library on June 9, 2015
which time all chickens had been fed the same diet, all groups had essentially identical performance. There was no effect of zeolite addition on the body weight or on feed utilization during the test period of 21 to 49 days. Chickens fed diets containing higher levels of added fat weighed more and had better feed utilization, but there was no interaction of dietary fat and zeolites. Chickens fed diets containing zeolite had slightly lower feed utilization values than those fed unsupplemented diets, but if corrected for the 1% inert material, the values would be almost identical. The results of these two experiments indicate that the addition of 1% zeolite to the diet of broiler chickens failed to have any beneficial effects on their performance to market age. Willis et al. (1982) demonstrated considerable differences in the response to zeolites from different geographical locations and it is possible that this may have accounted for the lack of response in these studies. However, in two previous studies from this station, the addition of a wide range of inert clays and fillers at several levels in the diet of broiler chickens failed to produce any improvement in performance of broilers (Waldroup and Ragland, 1977; Sellers et al, 1980). The present studies are in agreement with these reports.
1984 Poultry Science 63:1833-1836 INTRODUCTION
Zeolites, minerals of volcanic origin, are crystalline, hydrated aluminosilicates of alkali and alkaline earth cations, having an infinite, three-dimensional structure (Mumpton and Fishman, 1977). Hatieganu et al. (1979) reported that the addition of zeolites in the feed of broilers at between 5 and 9% improved growth 9 to 12% and feed utilization by 12%. Willis et al. (1982) reported that addition of certain zeolites to broiler rations at 21 days gave significant improvements in body weight gains and feed efficiency. Because previous studies from this station (Waldroup and Ragland, 1977; Sellers et al, 1980) failed to show response from the addition of different types of clays and inert fillers to broiler diets, studies were conducted to examine the possible response to addition of zeolites to the diet of broiler chickens. MATERIALS AND METHODS
Two experiments were conducted to determine the effects of zeolites on broiler chickens using diets considered to be adequate in all known nutrients. Diets used in this study were formulated to meet or exceed nutrient requirements suggested by the National Research Council (NRC, 1977) for the appropriate age. Diets contained yellow corn, soybean meal, a commercial animal-vegetable fat blend,
1 Published with the approval of the Director, Arkansas Agricultural Experiment Station.
and meat and bone meal as intact sources of energy and protein. Diets were fortified with vitamin and trace mineral mixes that were considered to be nutritionally adequate. Ingredient composition values reported by the NRC (1977) were used in formulation. The composition of diets used in these experiments is given in Table 1. In the first experiment, all diets were formulated to contain 3.20 kcal/g metabolizable energy, the base energy value used in establishing nutrient requirements by the NRC. In the second experiment, all chicks were fed to 21 days of age using the same formulation as used in Experiment 1. Three diet series were then used from 21 days to the conclusion of the study. These diets contained 1.25, 3.75, and 6.25% added fat in Series A, B, and C, respectively. Diets were formulated to optimum energy density with amino acids, calcium, and inorganic phosphorus maintained in ratio with energy. All diets contained monensin (99 mg/kg) from 1 to 42 days and zinc bacitracin (55 mg/kg) throughout the study. In both experiments, all chicks were fed a common basal diet from 1 to 21 days of age with test diets containing zeolite fed for the remainder of the study. Sexed chicks of a commercial broiler strain were obtained from a local hatchery and were randomly allocated into pens. In the first experiment there were 35 chicks of each sex per pen while in the second trial there were 25 chicks of each sex per pen. The pens were 5.2 m 2 and contained two hanging tube-type feeders and an automatic waterer. Wood shavings were used as litter over concrete floors.
1833
Downloaded from http://ps.oxfordjournals.org/ at Serials Section, Dixson Library on June 9, 2015
ABSTRACT Two experiments were conducted in which zeolites were added to broiler diets at the 1% level beginning at 21 days of age. In one study, diets with different energy levels were used to determine if an interaction existed between zeolite supplementation and nutrient density. No beneficial effects of zeolite supplementation on body weights were observed in either experiment. There were no statistically significant differences in feed utilization between diets with and without zeolites, and the numerical differences could be accounted for by the addition of 1% inert zeolite. (Key words, zeolites, broilers, nutrition)
3.07 19.22
18.00
100.00
19.86
3.18
100.00
3.11 17.53
20.51
3.32 18.70
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100.00 3.28
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62.62 27.34 6.25
1.42 1.83
1.44 1.94
1.42 1.83
66.62 25.28 3.75
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B
42 to 49 days
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Experiment 2
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57.44 31.88 6.25 0
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100.00
.49 .72 .40 .10 .50 .03
72.10 18.79 1.87 5.00
42 to 47 days
Supplied per kilogram of diet: 100 mg iron, 100 mg manganese, 100 mg zinc, 100 mg copper, 1 mg iodine.
20.00
100.00
100.00
23.00
.51 .64 .40 .10 .50 .10
.52 .51 .40 .10 .50 .23
3.20
65.83 24.04 2.88 5.00
56.38 31.95 4.41 5.00
3.20
21 to 42 days
Oto 21 days
21 to 42 days
Supplied per kilogram of diet: 6600 IU vitamin A, 2200 IU vitamin D 3 , 6.6 IU vitamim E, 3.3 mg menadione, 5.5 mg riboflavin, 33 mg niacin, 8.8 mg pantothenic acid, 495 mg choline, 1.1 mg thiamin, 1.1 mg pyridoxine, .0099 mg vitamin B 1 2 , .11 mg biotin, .66 mg folacin, 1 mg selenium, 62.5 mg ethoxyquin.
2
1
Calculated analysis Metabolizable energy, kcal/g Protein, %
Yellow corn Soybean meal Blended fats Meat and Bone meal Ground limestone Dicalcium phosphate Iodized salt Trace minerals 1 Vitamin premix 2 DL-Methionine Total
Ingredient
Experiment 1
TABLE 1. Composition of experimental diets (% of mixture)
om http://ps.oxfordjournals.org/ at Serials Section, Dixson Library on June 9, 2015
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ZEOLITES FOR BROILERS
1835
TABLE 2. Effects of zeolite supplementation on body weight gain and feed utilization by broilers (Experiment 1)
t ^
Body weight, g 21 days 42 days 47 days
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In the first trial, beginning at 21 days of age, 16 pens of chicks were fed the unsupplemented control diets while an equal number were fed a diet in which 1 part of corn was replaced with 1 part of zeolite. In the second experiment, each of the three diet series was fed without zeolite supplement. In three additional groups, 1 part of zeolite was blended with 99 parts of each of the three test diets. Each of these six treatment groups was fed to eight pens of chickens. In both studies, all diets were fed free-choice in pellet from. Body weights and feed consumption were determined at 21, 43, and 47 days of age in the first experiment and at 21, 42, and 49 days in the second experiment. Feed efficiency data were corrected for the weight of birds that died during the study. The data were subjected to the analysis of variance using SAS release 82.2B (SAS Institute, 1982).
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RESULTS
<*> "S, Ci.
In the first experiment, the replacement of 1 part of corn in the diet by an equal amount of zeolite had no effect on body weight at 42 or 47 days of age (Table 2). For the period from 21 to 47 days, during which time zeolite was fed, there were no significant differences in feed utilization between the treatment groups. Chickens fed the diet with zeolite generally had slightly lower feed utilization than those fed the unsupplemented control diet; however, if corrected for the 1% inert zeolite, values for the two treatments were almost identical. Similar results were found in the second experiment (Table 3). At 21 days of age, during
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Downloaded from http://ps.oxfordjournals.org/ at Serials Section, Dixson Library on June 9, 2015
Grams gain/gram feed 1 to 21 days 1 to 42 days 1 to 47 days 21 to 42 days 42 to 47 days
Plus zeolite
* *
X 0 0 N T-i ^ O 4»
No zeolite
• * .
1836
WALDROUP ET AL.
ACKNOWLEDGMENTS The authors express their appreciation to the Occidental Minerals Corporation and to PhelpsDodge Zeolites for financial support of these trials.
REFERENCES Hatieganu, V., I. Puia, O. Popa, and G. Baltan, 1979. Utilizarea zeolitilor naturali in hrana animalelor (sinteza). [The use of natural zeolites in the feeding of animals (synthesis)] . Zootech. Med. Vet. 33:27-34. Mumpton, F. A., and P. H. Fishman, 1977. The application of natural zeolites in animal sciences and aquaculture. J. Anim. Sci. 45:1188—1203. National Research Council, 1977. Nutrient Requirements of Domestic Animals. 1. Nutrient Requirements of Poultry. Natl. Acad. Sci., Washington, DC. SAS Institute, Inc., 1982. SAS User's Guide: Statistics, 1982 ed. SAS Inst., Cary, NC. Sellers, R. S., G. C. Harris, Jr., and P. W. Waldroup, 1980. The effects of various dietary clays and fillers on the performance of broilers and laying hens. Poultry Sci. 59:1901-1906. Waldroup, Park W., and D. R. Ragland, 1977. Spent filter clay as a potential feed ingredient for broiler diets. Nutr. Rep. Int. 16:249-254. Willis, W. L., C. L. Quarles, D. J. Fagerberg, and J. V. Shutze, 1982. Evaluation of zeolites fed to male broiler chickens. Poultry Sci. 61:438—442.
Downloaded from http://ps.oxfordjournals.org/ at Serials Section, Dixson Library on June 9, 2015
which time all chickens had been fed the same diet, all groups had essentially identical performance. There was no effect of zeolite addition on the body weight or on feed utilization during the test period of 21 to 49 days. Chickens fed diets containing higher levels of added fat weighed more and had better feed utilization, but there was no interaction of dietary fat and zeolites. Chickens fed diets containing zeolite had slightly lower feed utilization values than those fed unsupplemented diets, but if corrected for the 1% inert material, the values would be almost identical. The results of these two experiments indicate that the addition of 1% zeolite to the diet of broiler chickens failed to have any beneficial effects on their performance to market age. Willis et al. (1982) demonstrated considerable differences in the response to zeolites from different geographical locations and it is possible that this may have accounted for the lack of response in these studies. However, in two previous studies from this station, the addition of a wide range of inert clays and fillers at several levels in the diet of broiler chickens failed to produce any improvement in performance of broilers (Waldroup and Ragland, 1977; Sellers et al, 1980). The present studies are in agreement with these reports.