A Comparison of the Effect of Aureomycin in Combination with Three Levels of Sulfamethazine in Feed for the Control of Cecal Coccidiosis of Chickens

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1 DIFFERENTIAL BLOOD COUNTS 54 REFERENCES Lucas, A. M., and E. M. Denington, 157. Effect of total body x-ray irradiation on the blood of female Single Comb White Leghorn chickens. Poultry Sci. 6: Lucas, A. M., and C. Jamroz, in press. Atlas of Avian Hematology. Agriculture Monograph No. 5. U. S. Government Printing Office, Washington, D. C. Mainland, D., B. K. Coady and S. Joseph, 15. Observational variation in the differential blood count. Fol. Haem. 54: 8-1. A Comparison of the Effect of Aureomycin in Combination with Three Levels of Sulfamethazine in Feed for the Control of Cecal Coccidiosis of Chickens JOHN L. GARDINER Animal Disease and Parasite Research Division, Agricultural Research Service, U. S. Department of Agriculture, Beltsville, Maryland /^ARDINER (157) reported that ^-* young chickens kept in wire cages and inoculated experimentally with large numbers of sporulated oocysts of Eimeria tenella (1) did not die from cecal coccidiosis when fed growing mash medicated with sulfamethazine at a level of.15 percent, and () made weight gains equal to or somewhat better than uninfected control birds when aureomycin was added to the sulfamethazine-medicated mash at the rates of 1 and grams per ton. In the above-mentioned investigation, the amount of sulfamethazine included in the feed was kept constant, whereas the amount of aureomycin was varied. The present paper summarizes results of experiments in which birds were fed growing mash fortified with a constant amount of aureomycin, namely, grams per ton, and medicated with sulfamethazine at levels of.15,., and.5 percent. EXPERIMENTAL PROCEDURE The chicks used in these experiments were New Hampshire-Barred Rock crosses. (Received for publication October 11, 157) They were obtained from the Animal Husbandry Research Division when one day of age, and immediately placed in wire-floored brooders to lessen the chances of acquiring extraneous parasitic infections. Three experiments were carried out under as nearly identical conditions as possible. Each experiment involved one-week-old chicks, divided into 11 groups of 5 birds each. The chicks for the various groups were selected by weight, so that the total initial weight of each group was approximately equal to that of every other group. All birds comprising 1 of the 11 groups were inoculated with coccidia, each inoculated bird receiving, per os,, sporulated oocysts of E. tenella in.5 cc. of liquid. The scheme herein used for designating the various groups is the same as the one used in a previous report (Gardiner, 157). In each experiment one inoculated group (IC) and the uninoculated group () served as untreated controls.

2 55 J. L. GARDINER While on experiment, these groups were fed a growing mash to which neither sulfamethazine nor aureomycin was added. All of the other inoculated groups were fed growing mash containing sulfamethazine alone or in combination with aureomycin ( grams per ton) as follows: Three groups (A-1SS, A-15S,.4-55) were given continuously for the duration of the experiment a mash containing.15,., and.5 percent sulfamethazine, respectively, in combination with aureomycin in the amount named. Three other groups (155-4, 5-4, 55-4) received growing mash containing.15,., and.5 percent sulfamethazine only, respectively, for the first 7 days of the experiment, starting on the day of inoculation, and growing mash containing aureomycin only for the remainder of the experiment. The last groups (155-GJkf, 5-GM, 55-GJlf) received growing mash containing.15,., and.5 percent sulfamethazine only, respectively, for the first 7 days, starting at the time of inoculation, and growing mash only for the remainder of the experiment. On the ninth day after inoculation, 5 chicks from each group one of those that had made the poorest growth, one of those that had made the best growth, and at as nearly evenly spaced intervals as possible between these extremes in each group were killed for post-mortem examination. This was done to compare the effects of the different treatments at a time just following the peak of the disease and before recovery had begun. Each experiment was terminated at the end of days. EXPERIMENTAL FINDINGS The data are summarized in the accompanying tables and graph. Differences in results of the experiments are not great IC,4-155, * 5f 551 TABLE 1. Mortality No. birds No. deaths 4 1 Percent mortality = uninoculated control; IC=inoculated control; 4 = aureomycin; 5 = sulfamethazine; GM = growing mash. * Data represent combined results of groups and 155-GM. f Data represent combined results of groups 5-4 and 15S-GM. Data represent combined results of groups 55-4 and 55-GM. enough to be statistically significant. Consequently, data pertaining to groups handled alike in the experiments are combined for purposes of presentation of the data. As stated previously, during the first 7 days following inoculation, groups and 15S-GM, 5-4 and S-GM, and 55-4 and 55-GAf, respectively, received the same medication. They are, therefore, treated as groups rather than 6 for purposes of assessing mortality, pathology, and growth during the period in question. Mortality. Data with respect to mortality are summarized in Table 1. In contrast to a loss of 66 percent in the inoculated controls, no losses occurred in groups treated with sulfamethazine either alone at.15 percent or in combination with aureomycin at all levels. However, a mortality of 6 percent occurred in those groups which consumed mash containing sulfamethazine at a level of. percent and of 1 percent in those groups that were treated with this drug at a level of.5 percent, without aureomycin. These percentages of mortality proved to be highly significant when compared with those of either the inoculated controls or

3 CONTROL OF CECAL COCCIDIOSIS 551 IC * 5t 55* TABLE ;.--Pathology No. birds with cecal lesions of grade Ave. grade of lesions = uninoculated control; IC = inoculated control; 4 = aureomycin; 5=sulfamethazine; GM = growing mash. * Data represent combined results of groups and 155-GM. t Data represent combined results of groups 5-4 and S-GM. t Data represent combined results of groups 55-4 and Q5QS-GM. the groups in which mortality was completely suppressed. The difference in mortality between the groups receiving. percent sulfamethazine (5) and those receiving.5 percent (55) was also significant. Pathology. Data pertaining to pathology are summarized in Table. There was no very marked difference in gross pathology among the birds of the various treated groups, none of which showed lesions as severe as those in the inoculated controls. However, as can be seen, the lowest average grade of lesions among the treated groups was found in those birds fed the highest level (.15 percent) of sulfamethazine, whereas the highest average grade of lesions was found in those birds fed the lowest level (.5 percent) of this drug in the diet. Growth. Data on growth are summarized in Tables and 4. During the critical period of the disease, which is the 7 days following inoculation, the average gain per bird among the inoculated controls was only 5 percent of that attained by the uninoculated controls. Moreover, all of the inoculated-treated groups made A f 5* 55 IC TABLE. Weight gained, 7 days after inoculat Percent gain*, Ave. gain per bird (grams) T.., control; 4= aureomycin; 5=sulfamethazine; GM = growing mash. * Weight gain expressed as percent of total original weight of surviving birds. f Data represent combined results of and 15S-GM. t Data represent combined results of 5-4 and 5-GJW. Data represent combined results of 55-4 and 55-GAf. much better weight gains during this period than the inoculated controls, and all three levels of sulfamethazine in combination with aureomycin prevented any significant lowering of the average weight gain per bird, compared with normal growth as represented by the uninoculated controls. This last statement does not apply to those groups treated with sulfamethazine alone; the difference between their growth rates and those of both the uninoculated controls and the TABLE 4. Weight at end of experiment U5S-GM GM 55-GM Percent gain* Ave. gain per bird (grams) = uninoculated control; 4 = aureomycin; 5 = sulfamethazine; GM=growing mash. * Weight gain expressed as percent of total original weight of surviving birds.

4 55 J. L. GARDINER inoculated controls was statistically significant. The superior growth of birds fed mash containing.15 percent sulfamethazine as compared with those fed lesser amounts of this drug was also significant. Too few chicks in the inoculated control groups survived the first week of the experiment to make the data on their growth from that point to the end of the test of any importance. The surviving birds in all treated groups, with the single exception of those fed mash containing.5 percent sulfamethazine during the first 7 days and unfortified growing mash for the remainder of the test (55-GM"), made sufficient weight gains so that the difference between their growth and that of the uninoculated controls was of no significance. The three groups that were fed the sulfamethazine-aureomycin combinations throughout the experiment did as well as or better than the uninoculated controls. The three groups that consumed growing mash fortified with sulfamethazine at various levels during the first 7 days and with aureomycin alone thereafter grew better than their counterparts, which consumed only unfortified growing mash from the seventh day on; the differences were not significant, however. In the case of the two groups receiving. percent sulfamethazine for the first 7 days (S-.4 and 7SS-GM), the differences were very slight. The average gain per bird forms a good basis for comparison when mortality in the groups to be compared is equal, or approximately so. However, when one group suffers heavy mortality and another no mortality, a comparison on this basis alone can be very misleading. Figure 1 shows the total or gross gain made by each group as a whole. In order to achieve a fair comparison, the following compensations were deemed necessary. In the DAYS FIG. 1. Gross weight gain in pounds per group. case of a group that was one or two birds short for reasons outside the scope of the experiment, the missing complements were added at the value of the average weight per bird within the group. In the paired groups (15S-.4 and 15S-GM,,5-/1 and S-GM, 5QS-A and 55-GM), where mortality and growth records were shared for the first 7 days of the experiment, the average of the combined mortalities that occurred in the paired groups was taken to represent the total mortality of each group. For example, there was a total of deaths, 4 in group S-GM and 5 in 15S-A, from cecal coccidiosis among the birds treated with sulfamethazine at a level of. percent without aureomycin for the first 7 days. Therefore, 4 deaths were attributed to each group. In a computation of total weight from the seventh day on, onehalf of the average weight of one bird was subtracted from one group and added to

5 CONTROL OF CECAL COCCIDIOSIS 55 the other. On this basis, as shown in Figure 1, the total number of pounds of chicken in all three groups receiving both sulfamethazine and aureomycin throughout the experiment was equal to or greater than the total number of pounds of chicken in the uninoculated control group receiving unfortified, unmedicated growing mash. The groups that consumed growing mash containing.15 percent sulfamethazine without aureomycin for the first 7 days grossed somewhat less poundage for the same period, while the groups receiving the smaller percentages of sulfamethazine fell behind in gross poundage, this being largely a reflection of the heavier mortality suffered by them. DISCUSSION Under the conditions of these experiments, chicks receiving an inoculation of coccidial oocysts that killed 66 percent of the inoculated controls were completely protected from mortality by.15 percent sulfamethazine in the growing mash, with or without aureomycin. Chicks receiving smaller amounts of sulfamethazine (. and.5 percent) were also completely protected when the ration was fortified with aureomycin, but suffered mortality when only sulfamethazine was added to the growing mash. The mortality was in inverse proportion to the amount of sulfamethazine, and the differences were highly significant. The largest percentage of sulfamethazine (.15) most effectively suppressed pathology; the smallest percentage (.5) was the least effective. The addition of aureomycin apparently did little or nothing to prevent cecal lesions. The presence of aureomycin in the rations during the critical period of the disease had a significantly beneficial effect on the growth of the chicks. All inoculated groups that were fed mash containing both sulfamethazine and aureomycin had, at the conclusion of the experiment, made growth as good as or better than the uninoculated controls. When sulfamethazine only was added to the mash for the first 7 days, the groups that were given growing mash plus aureomycin as a follow-up made slightly better growth than did the groups that were given growing mash unfortified with aureomycin, but the difference was in no case significant. All of the groups fed both sulfamethazine and aureomycin continuously from the start of the experiment made better growth than did any of the groups that were treated with sulfamethazine only for the first 7 days. The data from tests herein reported indicate that the presence of aureomycin in the diet offset the toxic effects of the sulfamethazine and at the same time augmented the anticoccidial activity of the drug. However, aureomycin did not appear to be particularly effective as a growth stimulant after the damaging effects of the coccidial organisms had been overcome. These conclusions are valid only for chicks raised on wire and infected at an early age. It is possible that chicks raised on litter, or exposed to cecal coccidiosis at a later age, or both, might react differently to the same treatment. SUMMARY Under the conditions of these experiments, in chicks suffering from artificially induced cecal coccidiosis, the findings were as follows: 1. Sulfamethazine at.15,., and.5 percent, when combined with aureomycin at grams per ton of feed, gave complete protection from mortality and promoted normal growth.. Sulfamethazine at.15 percent of

6 554 J. L. GARDINER the diet, without aureomycin, gave complete protection from mortality, but normal growth was not maintained. Growth was, however, much better than in inoculated but unmedicated birds.. Sulfamethazine at. and.5 percent, without aureomycin, failed to give complete protection from mortality, especially at the lower amount, nor was normal growth maintained. Mortality INVESTIGATIONS concerning the use of arsenicals in the chick ration have been conducted on a large scale, since the early work of Morehouse and Mayfield (146) showed that these compounds stimulated chick growth. Similar investigations with mature birds have not been conducted as extensively; however, the research completed has indicated that such materials may also be of value for the later stages of growth and in the laying ration of the adult bird. For example, Morehouse (14), Pepper et al. (154) and Libby et al. (155) observed that time of sexual maturity was shortened by arsenical supplementation. Further, Libby et al. (155) showed that arsanilic acid increased egg production from. to 8.4 percent and increased the feed conversion slightly. Carlson el al. (155) reported that arsanilic acid supplementation increased egg pro- * Published with the approval of the director of the Colorado Agricultural Experiment Station. Project No. 51. was less and growth was greater, however, than in inoculated but unmedicated birds. 4. The addition of aureomycin to the diet after withdrawal of sulfamethazine did not significantly increase growth. REFERENCE Gardiner, J. L., 157. The effect of aureomycin and low-level sulfamethazine, separately and in combination, on cecal coccidiosis. Poultry Sci. 6: Egg Production and Reproduction as Affected by Arsanilic Acid and Penicillin* P. A. THORNTON AND R. E. MORENG Department of Poultry Husbandry, Colorado Agricultural Experiment Station, Fort Collins (Received for publication October 11, 157) duction in a 1 percent protein ration. In addition, these workers found that antibiotics increased feed efficiency but had no consistent effect on body weight maintenance, mortality, egg quality, or hatchability of fertile eggs. Price et al. (156) reported that -nitro-4-hydroxyphenyl arsonic acid increased egg production 4 to 6 percent and improved feed efficiency. Wharton and Fritz (15) found that arsanilic acid had no effect on either fertility or hatchability, and Libby et al. (15) made similar observations on hatchability. In the present study, the effect of arsanilic acid both in the absence and presence of penicillin was investigated. Observations include egg production, feed efficiency, maintenance of body weight, fertility, embryonic mortality, and hatchability. PROCEDURE Two hundred and forty-four Delaware and 4 S. C. White Leghorn strain-cross pullets were housed at random in four