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The Availability of Zinc in Various Compounds to Broad Breasted Bronze Poults1
340
T. W. SULLIVAN
Poultry Sci. 37: 1245-1246. Supplee, W. C , R. D. Creek, D. L. Blamberg and G. F . Combs, 1959. Zinc in poult diets. Poultry Sci. 38: 1253.
Young, R. J., H. M. Edwards, Jr. and M. B. Gillis, 1958. Studies on zinc in poultry nutrition. 2. Zinc requirement and deficiency symptoms of chicks. Poultry Sci. 37:1100-1107.
The Availability of Zinc in Various Compounds to Broad Breasted Bronze Poults 1 SULLIVAN
(Received for publication May 17, 1960)
A
CONSIDERABLE number of recent investigations have concerned the zinc requirement of chickens and turkeys. This work was stimulated by the results of studies conducted by O'Dell and Savage (1957) and Supplee et al. (1958). Compounds which have been used as zinc sources in the various investigations include zinc carbonate, zinc chloride, zinc oxide, zinc sulfate and certain zinc proteinates. A few comparisons have been made, but only one detailed study has been conducted to determine the biological availability of zinc from various sources to chicks and poults. Roberson and Schaible (1958) reported that the zinc in zinc sulfate and zinc chloride was equally available to starting chicks. One-hundred parts per million (ppm.) of zinc from each compound was added to a zinc-deficient, purified diet. This level of supplementary zinc, however, was more than three times the amount required by chicks. No definite conclusions regarding availability can be drawn from these data. Pensack et al. (1958) studied the relative growth-stimulating effect of several organic and inorganic zinc salts for chicks. Levels of 6, 20 1
Published with the approval of the Director as Paper No. 1036, Journal Series, Nebraska Agricultural Experiment Station.
and 40 ppm. of zinc from each source were added to a cerelose-casein-gelatin diet. Zinc was equally available from all sources (zinc carbonate, zinc oxide, zinc chloride and zinc proteinates) tested. Scott (1959) reported that zinc chloride, zinc oxide and possibly zinc carbonate could be used effectively in poultry rations. The results of Kienholz et al. (1959) indicated that the zinc in un-autoclaved field peas was not available to chicks, or that the peas contained a heat-labile factor which increased the requirement for zinc. Edwards (1959) has conducted a detailed study of the availability to chicks of zinc in various compounds and ores. Two levels, 10 and 20 ppm. of zinc from each material, were fed in a purified diet of low zinc content. The growth data obtained indicated that the zinc in zinc sulfate, willemite, zinc carbonate, zinc metal, zinc oxide (technical grade), smithsonite, hemirophite, zinc oxide (A.R. grade) and zincite was relatively available to the young growing chicken. The zinc in sterling black and brown crude ore was of lower availability and that from sphalerite and franklinite was relatively unavailable. The present investigation was undertaken to determine the relative availability of zinc from various compounds to Broad Breasted Bronze (BBB) poults.
Downloaded from http://ps.oxfordjournals.org/ at Purdue University Libraries ADMN on June 11, 2015
T . W.
Department of Poultry Husbandry, University of Nebraska, Lincoln 3, Nebraska
341
AVAILABILITY OF ZINC
EXPERIMENTAL PROCEDURE
The experiments were of 28 days duration. Individual body weights were taken at weekly intervals and the total diet consumption of the 20 birds assigned to each dietary treatment was determined at the termination of each experiment. When experiments 2 and 3 were terminated, the incidence of distinct zinc-deficiency symptoms in the legs and feathers of surviving birds was determined. When experiment 3 was terminated, three birds of TABLE 1.—Zinc compounds tested for availability of zinc to poults, 0-4 weeks of age Name and description Zinc carbonate (technical grade) Zinc chloride (A.R. grade) Zinc oxide (technical grade) Zinc sulfate (technical grade) Zinc sulfate (U.S.P. grade)
RESULTS AND DISCUSSION
The effect of supplementary zinc from various compounds on the growth of poults, 0-4 weeks of age, is shown by the data presented in Table 2. In experiment 1, where 40 ppm. of zinc from each compound was added to the basal diet, there were no significant differences between the gains of poults fed the various sources of supplementary zinc. The gains of those birds fed the unsupplemented basal diet were significantly less (P<.01) than the T A B L E 2.—Effect of supplementary zinc from various compounds on the growth of poults, 0-4 weeks of age. Average gain in 4 weeks, grams1'2 Source of supplementary zinc5
Experiment 1
210_
359
379
344
378
Experiment 2
_136
362
382
417
423
348 429
Experiments
146
259
244"
316
345
377
Formula ZnCk ZnO ZnSOt-HsO ZnS04-7H20
54.0 1 45.61 71.6 36.41 22.7
1 Samples and zinc analysis data furnished by the Calcium Carbonate Company, 520 South Fourth Street, Quincy, Illinois.
1 Any two means not underscored by the same line are significantly different at the 5 percent level. 2 Each value was computed from the gains of 16t 18 and 16 surviving birds per treatment, respectively, in experiments 1, 2 and3 3. The level of supplementary zinc added to the basal diet in each experiment was as follows: 40 ppm., experiment 1; 30 ppm., experiment 2; and 20 ppm., experiment 3. The basal diet contained 14 ppm. of zinc by analysis.
Downloaded from http://ps.oxfordjournals.org/ at Purdue University Libraries ADMN on June 11, 2015
Straight-run BBB poults were used in all three of the experiments. The basal diet, composed largely of isolated soybean protein and sucrose, was identical, and the experimental procedure followed was essentially the same as that described in an earlier publication (Sullivan, 1960). The name, formula and percentage of zinc in each of the compounds tested are shown in Table 1. The dietary treatments consisted of the basal diet plus either 20, 30 or 40 ppm., depending on the experiment involved, of zinc from each compound. The unsupplemented basal diet, which contained 14.2 ppm. of zinc by analysis, served as the negative control in each experiment. Each dietary treatment was fed to two replicate groups of 10 poults each. Precautions were taken to prevent the ingestion of unknown quantities of environmental zinc; the feed troughs were coated with a plastic-type (phenolic modified polyester) finish. Distilled water, which was dispensed in glass founts, and the experimental diets were supplied ad libitum.
average weight from each experimental group were sacrificed to obtain bone samples. A femur, a tibiotarsus and a tarsometatarsus were taken from each. After the adhering tissue was removed, the length of each bone was measured in centimeters. The growth data from all three experiments and the bone measurements from experiment 3 were subjected to analysis of variance (Snedecor, 1956). Duncan's (1953) New Multiple Range Test for significance was used to compare the treatment means when significant differences were detected by the analysis of variance. In every instance the level of significance is 5 percent, except where the 1 percent level is specifically indicated.
342
T. W. SULLIVAN
T A B L E 3.—Effect of supplementary zinc from various compounds on feed, efficiency and survival of poults, 0-4 weeks of age Source of supplementary zinc1 None Experiment 1 Feed/gain Survival Experiment 2 Feed/gain Survival
|9,4
ZnO
ZnO.
1.69 19/20
1.60 18/20
1.71 18/20
1.63 1.65 19/20 19/20
1.49 1.38 19/20 20/20
1.50 1.48 19/20 19/20
2.45 1.65 10/20 18/20 3.07 8/20
1.88 17/20
Z n 7 ^9!
ca°-
1.94 1.72 1.61 1.66 19/20 20/20 20/20 18/20
1 The level of supplementary zinc added to the basal diet in each experiment was as follows: 40 ppm., experiment 1; 30 ppm., experiment 2; and 20 ppm., experiment 3. The basal diet contained 14 ppm. of zinc by analysis.
gains of birds fed any of the supplemented diets; this was the case in each of the three experiments. In experiment 2 the compounds were compared by adding 30 ppm. of zinc from each to the basal diet. Differences in availability were then evidenced by differences in body weight gains; the gains of poults fed ZnS04-7H 2 0 and zinc carbonate were significantly greater than the gains of poults fed zinc oxide and ZnSC>4 • H 2 0 . The gains of poults fed zinc chloride were significantly greater than those of poults fed ZnS04-H 2 0. The difference in growth response to zinc oxide and ZnS(VH 2 0 was not significant. In experiment 3, 20 ppm. of zinc from each compound was added to the basal diet. The gains of poults fed zinc carbonate, ZnS04-7H 2 0, and zinc chloride were significantly greater than the gains of poults fed zinc oxide and ZnSCVH^O. The response to zinc carbonate was significantly greater than the response to zinc chloride, but not significantly greater than the response to ZnS04-7H 2 0. The difference in the response to zinc oxide and ZnSCV H 2 0 was not significant. The effect of supplementary zinc from various compounds on feed efficiency and survival is shown by the data presented in Table 3. The feed efficiency of birds fed
Linear bone growth was used as a criterion for determining zinc availability, because in previous studies both chicks and poults fed diets limiting in zinc exhibited a shortening and thickening of the long bones. The bone length data, presented in Table 4, were taken from experiment 3 and are in close agreement with the growth data obtained in that test. Femur and tarsometatarsus samples from poults fed zinc carbonate and ZnSCV 7H 2 0 were of significantly greater length than similar samples from poults fed the other compounds. Tibiotarsus samples from poults fed zinc carbonate and ZnSC>4 • 7H2O T A B L E 4.—Effect of supplementary zinc from various compounds on bone development in poults four weeks of age Average1 bone length in centimeters Source of supplementary zinc2
Femur Tibiotarsus Tarsometatarsus
ZnS0< None •HsO
ZnO
ZnCIj
3.73 5.22
4.15 5.85
4.23 5.88
4.42 6.28
4.77 6.57
4.97 6.95
3.87
4.35
4.53
4.60
5.25
5.08
Zinc ZnS04 car- -7HiO bonate
1 Each value represents the average of six individual bone measurements, three from each replicate group per treatment in experiment 3. See footnote 1 of Table 2. 2 Twenty ppm. of zinc from each compound was added to the basal diet which contained 14 ppm. of zinc by analysis.
Downloaded from http://ps.oxfordjournals.org/ at Purdue University Libraries ADMN on June 11, 2015
Experiment 3 Feed/gain Survival
2.09 9/20
Zn
the unsupplemented basal diet was much poorer than the feed efficiency of poults receiving any of the supplemented diets. In experiment 1 the various zinc supplements affected feed efficiency similarly; however, in experiment 2 the poults fed ZnS04-H 2 0 showed poorer feed efficiency than did poults receiving the other zinc compounds. In experiment 3 poults fed zinc carbonate and ZnSO,r7H 2 0 showed the best feed efficiency. These data are in general agreement with the growth data. The survival data indicate that mortality was not excessive in any of the groups fed supplementary zinc, while fewer than 50 percent of the control birds survived the four weeks experimental period.
AVAILABILITY OF ZINC
343
TABLE 5.—Ejfect of supplementary zinc from various compounds on the incidence1 of zinc-deficiency symptoms in poults four weeks of age Source of supplementary zinc2 ZnS0 4 -H 2 0
ZnO
ZnCla
ZnS0 4 -7H„0
Zinc carbonate
Experiment 2 Leg symptoms Feather symptoms
10/10 10/10
9/18 5/18
14/19 8/19
2/20 1/20
2/19 1/19
5/19 2/19
Experiment 3 Leg symptoms Feather symptoms
8/8 8/8
17/17 16/17
19/19 15/19
19/20 11/20
16/20 7/20
16/18 9/18
1
Incidence of deficiency symptoms in surviving birds at the termination of the experiment. The level of supplementary zinc added to the basal diet was 30 ppm. in experiment 2 and 20 ppm. in experiment 3. The basal diet contained 14 ppm. of zinc by analysis. 2
were of significantly greater length than samples from poults fed zinc oxide and ZnSCV H 2 0. There were no significant differences in the length of bone samples from poults fed zinc chloride, zinc oxide and ZnS0 4 -H 2 0. The effect of supplementary zinc from the various compounds on the incidence of zinc deficiency symptoms is shown by the data presented in Table 5. Zinc deficiency symptoms as evidenced by shortened legs, enlarged hocks and retarded feathering were exhibited by all of the surviving birds in the control groups. Poults fed zinc oxide and ZnSCVH^O showed a greater incidence of deficiency symptoms than did poults fed the other compounds. Practically all of the poults fed zinc oxide and ZnSCVH^O in experiment 3 showed abnormal bone and feather development, while poults fed the other compounds showed these conditions to a lesser degree. Abnormal leg development was definitely more pronounced than abnormal feather development in all of the groups. The data obtained in these experiments clearly indicate that the zinc in zinc carbonate and ZnS04-7H20 is readily available to starting poults. The zinc in zinc chloride was, perhaps, slightly less
available than the zinc in zinc carbonate and ZnS(V 7H 2 0. The deliquescent or hygroscopic nature of zinc chloride may have caused this to occur and would limit the use of this compound in poultry rations. Zinc oxide and ZnSOr H 2 0 were definitely inferior sources of zinc for starting turkey rations. These results are not in complete agreement with previously reported data. Edwards (1959) reported that the zinc in zinc oxide was equally or slightly more available than the zinc in ZnS04-7H 2 0. The zinc oxide and ZnS04-H 2 0 as well as the zinc carbonate used in the current study were technical grade compounds containing various impurities. It is possible, but quite unlikely, due to the amounts involved, that certain impurities could have been responsible for the relatively poor response to zinc oxide and ZnS04H20. In view of recent reports (Norris and Ziegler, 1959; Davis and Norris, 1960) there appears to be two distinct factors which influence the biological availability of minerals. These factors are: (1) the binding of metals by protein or some other moiety or additive in the diet such as free amino acids or ethylenediaminetetraacetic acid (EDTA) and (2) the particular solubility or some other property of the chem-
Downloaded from http://ps.oxfordjournals.org/ at Purdue University Libraries ADMN on June 11, 2015
None
344
T. W. SULLIVAN
ical form being used. In this study "availability" as determined by the latter has been investigated. The availability of zinc in the various compounds, as determined in this study, might be different in the presence of different proteins, other free amino acids or chelating agents such as EDTA. SUMMARY
ACKNOWLEDGMENT The author is grateful to the Central Soya Company, Inc., Chemurgy Division, 1825 Laramie Ave., Chicago 39, Illinois, for supplying the isolated soybean protein (Promine); to Merck and Company, Inc., Animal Science Research, Rahway, New Jersey, for supplying the vitamin B12, dbiotin, menadione, pyridoxine HC1, pteroylglutamic acid, riboflavin, thiamine HC1, calcium pantothenate and penicillin; to the Dow Chemical Company, Abbott Road Buildings, Midland, Michigan, for supplying the DL-methionine and glycine and to the Calcium Carbonate Company, 520 South Fourth Street, Quincy, Illinois
REFERENCES Davis, P. N., and L. C. Norris, 1960. Interference of soybean protein in the utilization of trace minerals. Informal Poultry Nutrition Conference, Chicago, 111. Duncan, D. B., 1953. Significant tests for differences between ranked treatments in analysis of variance. Technical Report No. 3, June 1953, Department of Statistics, Virginia Agri. Expt. Sta., Blacksburg, Va. Edwards, H. M., Jr., 1959. The availability to chicks of zinc in various compounds and ores. J. Nutrition, 69: 306-308. Kienholz, E. W., L. S. Jensen and J. McGinnis, 1959. Influence of autoclaving peas on response of chicks to supplemental zinc. Poultry Sci. 38:1218. Norris, L. C , and T. R. Ziegler, 1959. Some results of studies on the zinc requirements of chicks. Cornell Feed Service, No. 52: 1-3. O'Dell, B. L., and J. E. Savage, 1957. Potassium, zinc and distillers dried solubles as supplements to a purified diet. Poultry Sci. 36: 459-460. Pensack, J. M., J. N. Henson and P. D. Bogdonoff, 1958. The effects of calcium and phosphorus on the zinc requirements of growing chickens. Poultry Sci. 37: 1232-1233. Roberson, R. H., and P. J. Schaible, 1958. The zinc requirement of the chick. Poultry Sci. 37: 13211323. Scott, M. L., 1959. Zinc is important in rations for turkeys. Cornell Feed Service, No. 52: 3-4. Snedecor, G. W., 1956. Statistical Methods. 5th ed. The Iowa State College Press, Ames, Iowa. Sullivan, T. W., 1960. The zinc requirement of Broad Breasted Bronze poults. Poultry Sci. 40: 334-340. Supplee, W. C , G. F. Combs and D. L. Blamberg, 1958. Zinc and potassium effects on bone formation, feathering and growth of poults. Poultry Sci. 37:63-67.
AUGUST 8-11. POULTRY SCIENCE ASSOCIATION, ANNUAL MEETING, PENNSYLVANIA STATE UNIVERSITY, UNIVERSITY PARK, PA.
Downloaded from http://ps.oxfordjournals.org/ at Purdue University Libraries ADMN on June 11, 2015
The effect of supplementary zinc from various compounds on growth, survival, feed efficiency, bone development and the incidence of deficiency symptoms was studied in three experiments with Broad Breasted Bronze poults, 0-4 weeks of age. The results obtained indicate that the zinc in zinc carbonate and ZnS04 • 7H2O is readily available. The zinc in zinc chloride was, perhaps, slightly less available than the zinc in zinc carbonate and ZnSC>4 •7H 2 0. Zinc oxide and ZnS04-H 2 0 were relatively inferior sources of dietary zinc for poults.
for supplying the calcium carbonate, zinc carbonate, zinc oxide and zinc sulfate (ZnS04-H 2 0) used in this study. A grantin-aid which partially supported the work was also furnished by the Calcium Carbonate Company.
T. W. SULLIVAN
Poultry Sci. 37: 1245-1246. Supplee, W. C , R. D. Creek, D. L. Blamberg and G. F . Combs, 1959. Zinc in poult diets. Poultry Sci. 38: 1253.
Young, R. J., H. M. Edwards, Jr. and M. B. Gillis, 1958. Studies on zinc in poultry nutrition. 2. Zinc requirement and deficiency symptoms of chicks. Poultry Sci. 37:1100-1107.
The Availability of Zinc in Various Compounds to Broad Breasted Bronze Poults 1 SULLIVAN
(Received for publication May 17, 1960)
A
CONSIDERABLE number of recent investigations have concerned the zinc requirement of chickens and turkeys. This work was stimulated by the results of studies conducted by O'Dell and Savage (1957) and Supplee et al. (1958). Compounds which have been used as zinc sources in the various investigations include zinc carbonate, zinc chloride, zinc oxide, zinc sulfate and certain zinc proteinates. A few comparisons have been made, but only one detailed study has been conducted to determine the biological availability of zinc from various sources to chicks and poults. Roberson and Schaible (1958) reported that the zinc in zinc sulfate and zinc chloride was equally available to starting chicks. One-hundred parts per million (ppm.) of zinc from each compound was added to a zinc-deficient, purified diet. This level of supplementary zinc, however, was more than three times the amount required by chicks. No definite conclusions regarding availability can be drawn from these data. Pensack et al. (1958) studied the relative growth-stimulating effect of several organic and inorganic zinc salts for chicks. Levels of 6, 20 1
Published with the approval of the Director as Paper No. 1036, Journal Series, Nebraska Agricultural Experiment Station.
and 40 ppm. of zinc from each source were added to a cerelose-casein-gelatin diet. Zinc was equally available from all sources (zinc carbonate, zinc oxide, zinc chloride and zinc proteinates) tested. Scott (1959) reported that zinc chloride, zinc oxide and possibly zinc carbonate could be used effectively in poultry rations. The results of Kienholz et al. (1959) indicated that the zinc in un-autoclaved field peas was not available to chicks, or that the peas contained a heat-labile factor which increased the requirement for zinc. Edwards (1959) has conducted a detailed study of the availability to chicks of zinc in various compounds and ores. Two levels, 10 and 20 ppm. of zinc from each material, were fed in a purified diet of low zinc content. The growth data obtained indicated that the zinc in zinc sulfate, willemite, zinc carbonate, zinc metal, zinc oxide (technical grade), smithsonite, hemirophite, zinc oxide (A.R. grade) and zincite was relatively available to the young growing chicken. The zinc in sterling black and brown crude ore was of lower availability and that from sphalerite and franklinite was relatively unavailable. The present investigation was undertaken to determine the relative availability of zinc from various compounds to Broad Breasted Bronze (BBB) poults.
Downloaded from http://ps.oxfordjournals.org/ at Purdue University Libraries ADMN on June 11, 2015
T . W.
Department of Poultry Husbandry, University of Nebraska, Lincoln 3, Nebraska
341
AVAILABILITY OF ZINC
EXPERIMENTAL PROCEDURE
The experiments were of 28 days duration. Individual body weights were taken at weekly intervals and the total diet consumption of the 20 birds assigned to each dietary treatment was determined at the termination of each experiment. When experiments 2 and 3 were terminated, the incidence of distinct zinc-deficiency symptoms in the legs and feathers of surviving birds was determined. When experiment 3 was terminated, three birds of TABLE 1.—Zinc compounds tested for availability of zinc to poults, 0-4 weeks of age Name and description Zinc carbonate (technical grade) Zinc chloride (A.R. grade) Zinc oxide (technical grade) Zinc sulfate (technical grade) Zinc sulfate (U.S.P. grade)
RESULTS AND DISCUSSION
The effect of supplementary zinc from various compounds on the growth of poults, 0-4 weeks of age, is shown by the data presented in Table 2. In experiment 1, where 40 ppm. of zinc from each compound was added to the basal diet, there were no significant differences between the gains of poults fed the various sources of supplementary zinc. The gains of those birds fed the unsupplemented basal diet were significantly less (P<.01) than the T A B L E 2.—Effect of supplementary zinc from various compounds on the growth of poults, 0-4 weeks of age. Average gain in 4 weeks, grams1'2 Source of supplementary zinc5
Experiment 1
210_
359
379
344
378
Experiment 2
_136
362
382
417
423
348 429
Experiments
146
259
244"
316
345
377
Formula ZnCk ZnO ZnSOt-HsO ZnS04-7H20
54.0 1 45.61 71.6 36.41 22.7
1 Samples and zinc analysis data furnished by the Calcium Carbonate Company, 520 South Fourth Street, Quincy, Illinois.
1 Any two means not underscored by the same line are significantly different at the 5 percent level. 2 Each value was computed from the gains of 16t 18 and 16 surviving birds per treatment, respectively, in experiments 1, 2 and3 3. The level of supplementary zinc added to the basal diet in each experiment was as follows: 40 ppm., experiment 1; 30 ppm., experiment 2; and 20 ppm., experiment 3. The basal diet contained 14 ppm. of zinc by analysis.
Downloaded from http://ps.oxfordjournals.org/ at Purdue University Libraries ADMN on June 11, 2015
Straight-run BBB poults were used in all three of the experiments. The basal diet, composed largely of isolated soybean protein and sucrose, was identical, and the experimental procedure followed was essentially the same as that described in an earlier publication (Sullivan, 1960). The name, formula and percentage of zinc in each of the compounds tested are shown in Table 1. The dietary treatments consisted of the basal diet plus either 20, 30 or 40 ppm., depending on the experiment involved, of zinc from each compound. The unsupplemented basal diet, which contained 14.2 ppm. of zinc by analysis, served as the negative control in each experiment. Each dietary treatment was fed to two replicate groups of 10 poults each. Precautions were taken to prevent the ingestion of unknown quantities of environmental zinc; the feed troughs were coated with a plastic-type (phenolic modified polyester) finish. Distilled water, which was dispensed in glass founts, and the experimental diets were supplied ad libitum.
average weight from each experimental group were sacrificed to obtain bone samples. A femur, a tibiotarsus and a tarsometatarsus were taken from each. After the adhering tissue was removed, the length of each bone was measured in centimeters. The growth data from all three experiments and the bone measurements from experiment 3 were subjected to analysis of variance (Snedecor, 1956). Duncan's (1953) New Multiple Range Test for significance was used to compare the treatment means when significant differences were detected by the analysis of variance. In every instance the level of significance is 5 percent, except where the 1 percent level is specifically indicated.
342
T. W. SULLIVAN
T A B L E 3.—Effect of supplementary zinc from various compounds on feed, efficiency and survival of poults, 0-4 weeks of age Source of supplementary zinc1 None Experiment 1 Feed/gain Survival Experiment 2 Feed/gain Survival
|9,4
ZnO
ZnO.
1.69 19/20
1.60 18/20
1.71 18/20
1.63 1.65 19/20 19/20
1.49 1.38 19/20 20/20
1.50 1.48 19/20 19/20
2.45 1.65 10/20 18/20 3.07 8/20
1.88 17/20
Z n 7 ^9!
ca°-
1.94 1.72 1.61 1.66 19/20 20/20 20/20 18/20
1 The level of supplementary zinc added to the basal diet in each experiment was as follows: 40 ppm., experiment 1; 30 ppm., experiment 2; and 20 ppm., experiment 3. The basal diet contained 14 ppm. of zinc by analysis.
gains of birds fed any of the supplemented diets; this was the case in each of the three experiments. In experiment 2 the compounds were compared by adding 30 ppm. of zinc from each to the basal diet. Differences in availability were then evidenced by differences in body weight gains; the gains of poults fed ZnS04-7H 2 0 and zinc carbonate were significantly greater than the gains of poults fed zinc oxide and ZnSC>4 • H 2 0 . The gains of poults fed zinc chloride were significantly greater than those of poults fed ZnS04-H 2 0. The difference in growth response to zinc oxide and ZnS(VH 2 0 was not significant. In experiment 3, 20 ppm. of zinc from each compound was added to the basal diet. The gains of poults fed zinc carbonate, ZnS04-7H 2 0, and zinc chloride were significantly greater than the gains of poults fed zinc oxide and ZnSCVH^O. The response to zinc carbonate was significantly greater than the response to zinc chloride, but not significantly greater than the response to ZnS04-7H 2 0. The difference in the response to zinc oxide and ZnSCV H 2 0 was not significant. The effect of supplementary zinc from various compounds on feed efficiency and survival is shown by the data presented in Table 3. The feed efficiency of birds fed
Linear bone growth was used as a criterion for determining zinc availability, because in previous studies both chicks and poults fed diets limiting in zinc exhibited a shortening and thickening of the long bones. The bone length data, presented in Table 4, were taken from experiment 3 and are in close agreement with the growth data obtained in that test. Femur and tarsometatarsus samples from poults fed zinc carbonate and ZnSCV 7H 2 0 were of significantly greater length than similar samples from poults fed the other compounds. Tibiotarsus samples from poults fed zinc carbonate and ZnSC>4 • 7H2O T A B L E 4.—Effect of supplementary zinc from various compounds on bone development in poults four weeks of age Average1 bone length in centimeters Source of supplementary zinc2
Femur Tibiotarsus Tarsometatarsus
ZnS0< None •HsO
ZnO
ZnCIj
3.73 5.22
4.15 5.85
4.23 5.88
4.42 6.28
4.77 6.57
4.97 6.95
3.87
4.35
4.53
4.60
5.25
5.08
Zinc ZnS04 car- -7HiO bonate
1 Each value represents the average of six individual bone measurements, three from each replicate group per treatment in experiment 3. See footnote 1 of Table 2. 2 Twenty ppm. of zinc from each compound was added to the basal diet which contained 14 ppm. of zinc by analysis.
Downloaded from http://ps.oxfordjournals.org/ at Purdue University Libraries ADMN on June 11, 2015
Experiment 3 Feed/gain Survival
2.09 9/20
Zn
the unsupplemented basal diet was much poorer than the feed efficiency of poults receiving any of the supplemented diets. In experiment 1 the various zinc supplements affected feed efficiency similarly; however, in experiment 2 the poults fed ZnS04-H 2 0 showed poorer feed efficiency than did poults receiving the other zinc compounds. In experiment 3 poults fed zinc carbonate and ZnSO,r7H 2 0 showed the best feed efficiency. These data are in general agreement with the growth data. The survival data indicate that mortality was not excessive in any of the groups fed supplementary zinc, while fewer than 50 percent of the control birds survived the four weeks experimental period.
AVAILABILITY OF ZINC
343
TABLE 5.—Ejfect of supplementary zinc from various compounds on the incidence1 of zinc-deficiency symptoms in poults four weeks of age Source of supplementary zinc2 ZnS0 4 -H 2 0
ZnO
ZnCla
ZnS0 4 -7H„0
Zinc carbonate
Experiment 2 Leg symptoms Feather symptoms
10/10 10/10
9/18 5/18
14/19 8/19
2/20 1/20
2/19 1/19
5/19 2/19
Experiment 3 Leg symptoms Feather symptoms
8/8 8/8
17/17 16/17
19/19 15/19
19/20 11/20
16/20 7/20
16/18 9/18
1
Incidence of deficiency symptoms in surviving birds at the termination of the experiment. The level of supplementary zinc added to the basal diet was 30 ppm. in experiment 2 and 20 ppm. in experiment 3. The basal diet contained 14 ppm. of zinc by analysis. 2
were of significantly greater length than samples from poults fed zinc oxide and ZnSCV H 2 0. There were no significant differences in the length of bone samples from poults fed zinc chloride, zinc oxide and ZnS0 4 -H 2 0. The effect of supplementary zinc from the various compounds on the incidence of zinc deficiency symptoms is shown by the data presented in Table 5. Zinc deficiency symptoms as evidenced by shortened legs, enlarged hocks and retarded feathering were exhibited by all of the surviving birds in the control groups. Poults fed zinc oxide and ZnSCVH^O showed a greater incidence of deficiency symptoms than did poults fed the other compounds. Practically all of the poults fed zinc oxide and ZnSCVH^O in experiment 3 showed abnormal bone and feather development, while poults fed the other compounds showed these conditions to a lesser degree. Abnormal leg development was definitely more pronounced than abnormal feather development in all of the groups. The data obtained in these experiments clearly indicate that the zinc in zinc carbonate and ZnS04-7H20 is readily available to starting poults. The zinc in zinc chloride was, perhaps, slightly less
available than the zinc in zinc carbonate and ZnS(V 7H 2 0. The deliquescent or hygroscopic nature of zinc chloride may have caused this to occur and would limit the use of this compound in poultry rations. Zinc oxide and ZnSOr H 2 0 were definitely inferior sources of zinc for starting turkey rations. These results are not in complete agreement with previously reported data. Edwards (1959) reported that the zinc in zinc oxide was equally or slightly more available than the zinc in ZnS04-7H 2 0. The zinc oxide and ZnS04-H 2 0 as well as the zinc carbonate used in the current study were technical grade compounds containing various impurities. It is possible, but quite unlikely, due to the amounts involved, that certain impurities could have been responsible for the relatively poor response to zinc oxide and ZnS04H20. In view of recent reports (Norris and Ziegler, 1959; Davis and Norris, 1960) there appears to be two distinct factors which influence the biological availability of minerals. These factors are: (1) the binding of metals by protein or some other moiety or additive in the diet such as free amino acids or ethylenediaminetetraacetic acid (EDTA) and (2) the particular solubility or some other property of the chem-
Downloaded from http://ps.oxfordjournals.org/ at Purdue University Libraries ADMN on June 11, 2015
None
344
T. W. SULLIVAN
ical form being used. In this study "availability" as determined by the latter has been investigated. The availability of zinc in the various compounds, as determined in this study, might be different in the presence of different proteins, other free amino acids or chelating agents such as EDTA. SUMMARY
ACKNOWLEDGMENT The author is grateful to the Central Soya Company, Inc., Chemurgy Division, 1825 Laramie Ave., Chicago 39, Illinois, for supplying the isolated soybean protein (Promine); to Merck and Company, Inc., Animal Science Research, Rahway, New Jersey, for supplying the vitamin B12, dbiotin, menadione, pyridoxine HC1, pteroylglutamic acid, riboflavin, thiamine HC1, calcium pantothenate and penicillin; to the Dow Chemical Company, Abbott Road Buildings, Midland, Michigan, for supplying the DL-methionine and glycine and to the Calcium Carbonate Company, 520 South Fourth Street, Quincy, Illinois
REFERENCES Davis, P. N., and L. C. Norris, 1960. Interference of soybean protein in the utilization of trace minerals. Informal Poultry Nutrition Conference, Chicago, 111. Duncan, D. B., 1953. Significant tests for differences between ranked treatments in analysis of variance. Technical Report No. 3, June 1953, Department of Statistics, Virginia Agri. Expt. Sta., Blacksburg, Va. Edwards, H. M., Jr., 1959. The availability to chicks of zinc in various compounds and ores. J. Nutrition, 69: 306-308. Kienholz, E. W., L. S. Jensen and J. McGinnis, 1959. Influence of autoclaving peas on response of chicks to supplemental zinc. Poultry Sci. 38:1218. Norris, L. C , and T. R. Ziegler, 1959. Some results of studies on the zinc requirements of chicks. Cornell Feed Service, No. 52: 1-3. O'Dell, B. L., and J. E. Savage, 1957. Potassium, zinc and distillers dried solubles as supplements to a purified diet. Poultry Sci. 36: 459-460. Pensack, J. M., J. N. Henson and P. D. Bogdonoff, 1958. The effects of calcium and phosphorus on the zinc requirements of growing chickens. Poultry Sci. 37: 1232-1233. Roberson, R. H., and P. J. Schaible, 1958. The zinc requirement of the chick. Poultry Sci. 37: 13211323. Scott, M. L., 1959. Zinc is important in rations for turkeys. Cornell Feed Service, No. 52: 3-4. Snedecor, G. W., 1956. Statistical Methods. 5th ed. The Iowa State College Press, Ames, Iowa. Sullivan, T. W., 1960. The zinc requirement of Broad Breasted Bronze poults. Poultry Sci. 40: 334-340. Supplee, W. C , G. F. Combs and D. L. Blamberg, 1958. Zinc and potassium effects on bone formation, feathering and growth of poults. Poultry Sci. 37:63-67.
AUGUST 8-11. POULTRY SCIENCE ASSOCIATION, ANNUAL MEETING, PENNSYLVANIA STATE UNIVERSITY, UNIVERSITY PARK, PA.
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The effect of supplementary zinc from various compounds on growth, survival, feed efficiency, bone development and the incidence of deficiency symptoms was studied in three experiments with Broad Breasted Bronze poults, 0-4 weeks of age. The results obtained indicate that the zinc in zinc carbonate and ZnS04 • 7H2O is readily available. The zinc in zinc chloride was, perhaps, slightly less available than the zinc in zinc carbonate and ZnSC>4 •7H 2 0. Zinc oxide and ZnS04-H 2 0 were relatively inferior sources of dietary zinc for poults.
for supplying the calcium carbonate, zinc carbonate, zinc oxide and zinc sulfate (ZnS04-H 2 0) used in this study. A grantin-aid which partially supported the work was also furnished by the Calcium Carbonate Company.