P O U LTOS CIE N G E

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1 P O U LTOS CIE N G E January, 1943? Vol. XXII, No. 1 The Relative Efficiency of Gains in Weight Made by Male and Female Bronze Turkeys* CONSIDERABLE data have been collected on feed used by turkeys at different age and weight periods but the greater part has been based on flocks composed of both sexes, with limited information having been obtained where the sexes were separated. Data reported by Brooks (1933) on Bourbon Red turkeys from 1 to 2 of age with and separated, showed male turkeys used feed more efficiently than ; that is, a pound of weight was produced on less feed by the than by the. The average gains were greater and more consistent each week for than for. ate more feed each week per bird than but less in relation to their body weight or gain in weight than. Bourbon Red raised in strict confinement consumed an average of 6.0 pounds of feed per pound of gain made between the ages of 1 and 2, while during the same period consumed an average of.2 pounds of feed per pound of gain. * Contribution from the Department of Poultry Husbandry, Missouri Agricultural Experiment Station. Journal Series No. 25. E. M. FUNK University of Missouri, Columbia, Missouri (Received for publication May IS, 1942) [3] Barrett et al. (1940) reported that male turkeys made more economical gains than both in feed required per pound of gain and cost in cents per pound of gain. Their data showed that consumed relatively more grain than during a given period. Robertson and Wilhelm (1940) reported that efficiency of feed utilization in turkeys was very high in all groups of birds on experiment during the first part of the growing period, particularly to the age of 16. Although hens ate less feed than the toms, the efficiency of their feed utilization up to 16 of age was only slightly lower than that of the toms. From data accumulated they found that the following amount of feed was required to produce a pound of live turkey from 9 to 2 : all-mash (confined), toms S.OS pounds and 5.22 pounds; all-mash (range), toms 4.61 pounds and 5.2 pounds; and whole grains (range), toms 3.4 and 4.39 pounds; mash and whole grains (range), toms 4.3 pounds and 4.6 pounds. Roberts (1940) reported the results of two feeding trials which showed that from

2 4 E. M. FUNK the twelfth to the twenty-fourth of age the consumed 5.2 and 4.93 pounds of feed per pound of gain as compared to 5.5 and 5.21 pounds of feed per pound of gain made by the'. All work thus far reported indicates that the male turkey is a more efficient producer of turkey meat than the female turkey. Harshaw (1940) reported that at 2 of age the edible portions of the male turkey were 20.4 percent protein and 19.7 percent for the. The fat content at the same age was 13.2 and 13.5 percent for and, respectively. EXPERIMENTAL PROCEDURE In 1940 and in experiments were designed at the Missouri Agricultural Experiment Station to determine if there were significant sexual differences in feed utilization by turkeys. Bronze turkey poults were hatched from turkey breeding stock maintained on the University of Missouri poultry farm. An effort was made to use poults of similar breeding and vitality in all lots. In 1940 eight lots of poults were used in the experiment, four lots of and four lots of. Male lots 4011 and 40 and female lots 4013 and 4014 were hatched June 22, and male lots 4015 and 4016 and female lots 4017 and 401 were hatched July 6. Sex was determined by the method described by Marsden and Martin (1939). This method consisted of an examination of the portion of the sex organs that can be seen in the vent. Some difficulty was experienced in determining sex accurately at hatching time and because of this no lot was 100 percent accurate for its sex up to 1, at which time the birds were sexed by plumage color and external characteristics and placed in their proper lots. By 1 it was discovered that of the 110 birds in the male lots were, and of the 96 birds in the female lots 14 were. Therefore, the male lots contained 93 percent from hatching to 1 of age and 100 percent thereafter. The female lots contained 5 percent from hatching to 1 of age and 100 percent from 1 to In the poults were hatched May 2 and the and were separated into their respective lots at 16 of age. All lots were given the same treatment. The poults were started in batteries, being moved to colony houses when they were four of age. The poults were confined to the 10 by foot brooder houses until eight of age, after which time they were allowed to run in an by foot sun porch with wire floor as well as having access to the brooder house. Straw was used as litter in all pens. The birds remained under these conditions to the completion of the experiment. In 1940 a ration which had given good results in previous feeding experiments was fed. This ration and water were kept be* fore the poults all the time. Whole yellow corn was fed ad libitum after the poults were 16 - old. Grit was kept before the birds after 16 of age but no green feed was used. The following mash mixture was used: Pounds Yellow corn meal '.. 42 Wheat bran 15 Wheat shorts 10 Alfalfa leaf meal 5 Meat scrap 10 Dried buttermilk 5 Soybean oil meal 10 Salt ' 1 Cod liver oil 2 All the poults were weighed individually every two and the feed consumed was determined at the same time. For the first 6 the poults were weighed in grams, pounds being computed from the gram weights. After six the poults

3 EFFICIENCY IN GAINS IN WEIGHT MADE BY MALE AND FEMALE TURKEYS 5 TABLE 1. Efficiency of gains {pounds of feed per pound gain) made by male and female bronze turkeys hatched June 22, 1940, and raised in complete confinement. TABLE 2. Efficiency of gains (pounds of feed per pound of gain) made by male and female Bronze turkeys hatched July 6, 1940, and raised in complete confinement. Period Number of turkeys and feed were weighed by scales weighing in tenths of a pound. The average gain per bird was determined by subtracting the average weight at the beginning of the period from the average weight at the end of the period. The feed consumed per bird was determined on a turkey-day basis by dividing the total consumption for the period by the number of birds in the lot during that period. Efficiency of gains was calculated by dividing feed consumed per bird by average gain per bird. TABLE 3. Efficiency Difference 21 of gains (pounds feed per pound gain) made by male and female Bronze turkeys hatched May 2,, and raised in complete confinement Period Number of turkeys In, all lots were fed for the first an all-mash starter similar to the one used in 1940 but beginning the ninth week all lots had whole yellow corn and whole oats before them in hoppers and lots 4101, 4102, 4103, and 4104 had access, respectively, to mash mixtures containing the following percentages of protein: 40, 36, 32, and 27. Each lot was divided into and after the sixteenth week but both sexes of each lot received the same feeding regimen

4 6 E. M. FUNK TABLE 4. Cost of gains (protein per pound gain) made by male and female Bronze turkeys raised in complete confinement on different protein mixtures.* Hatched May 2, Difference % % % % * This table was calculated from tables of composition of feedstuffs as given by Henry and Morrison. TABLE 5. Cost of gains (carbohydrates+fatx2.25 per pound of gain) made by male and female Bronze turkeys raised in complete confinement on different protein mixtures* Hatched May 2, Difference % % % , 4.72 * This table was calculated from tables of composition of feedstuffs as given by Henry and Morrison and the feed records of this experiment. TABLE 6. Cost of gains (cents per pound of gain) made by male and female Bronze turkeys raised in complete confinement on different mixtures. Hatched May 2, %

5 EFFICIENCY IN GAINS IN WEIGHT MADE BY MALE AND FEMALE TURKEYS 7 TABLE 7. Rate* of growth in male and female Bronze turkeys. 101 and Period R (male) R (female) R (female) R (male) * Rate of growth was calculated by the formula W 2 -Wi R= X100 where Wi = weight at the. i(w ^w,) _ beginning of a period and Ws=weight at the end of the same period. RESULTS The results obtained in these experiments were similar to those reported by TABLE. Relative amounts of a 21 percent protein mash and whole yellow corn consumed by male and female Bronze turkeys hatched in 1940 and reared in complete confinement. Mash containing 21 percent protein Whole yellow corn other investigators. Male turkeys produced more economical gains than after the sixteenth week of age and the relative efficiency of the male increased up to the thirtieth week. During the first 16 there was apparently no significant sexual differences in economy of gains. TABLE 9. The effect of age, sex, and percentage of protein on the consumption of mixtures by Bronze turkeys. Figures show the percentage of consumed. Hatched May 2, Year TABLE 10. Significance of the differences in economy of gains made by male and female turkeys in favor of the Period Conditions Pounds of feed per pound of gain Pounds of protein per pound of gain Carbonaceous material per pound of gain Cost in cents per pound of gain Pounds of feed per pound of gain Pounds of protein per pound of gain Carbonaceous material per pound of gain Cost in cents per pound of gain Pounds of feed per pound of gain F F values whenp=

6 E. M. FUNK AGE WEEKS FIG 1. Consumption of mash and grain by male and female Bronze turkeys from the seventeenth to twenty-sixth of age. The mash contained 21 percent protein and the grain was corn. POUNDS OF FEED REQUIRED TO PRODUCE A POUND OF GAIN IN MALE AND FEMALE TURKEYS Since the turkey is a meat producing animal its efficiency should be judged by its economy in gains made up to market age. In 1940, during the first 1 weeke, the male turkeys as shown in Tables 1 and 2 required 3.20, 3.17, 3.47, and 3.2 pounds of feed per pound of gain as compared to 3.23, 3.49, 3.73, and 3.63 pounds of feed for of the same age. From 19 to 24 of age these same lots of for each pound of gain consumed 6.30, S.69, S.4S, and 6.77 pounds of feed as compared to 6.67,.0, 9.34, and 7.60 pounds for the. Table 3 shows that, with four lots of male and female Bronze turkeys raised in on different rations, the in each lot required less feed to produce a pound of gain than did the. For the period from the seventeenth to the thirtieth, the differences for the four lots were 0.61, 1.03, 1.1, and 1.39 pounds of feed each in favor of the. As female turkeys are usually finished and ready for market about two before the are equally finished, the differences were calculated for the to 26 and the to 2 of age. The differences remained highly significant, favoring the. The difference in economy of gains made by male and female turkeys in both 1940 and were found to be highly significant when tested by Snedecor's method for the analysis of variance (Table 10). UTILIZATION OF NUTRIENTS BY MALE AND FEMALE TURKEYS Since the turkeys raised in were fed mixtures containing different AGE WEEKS 27% PROTEIN CONCENTRATE FIG. 2. Consumption of mash and grain by male and female Bronze turkeys from the seventeenth to thirtieth of age. The mash contained 27 percent protein and the grains were corn and oats.

7 EFFICIENCY IN GAINS IN WEIGHT MADE BY MALE AND FEMALE TURKEYS 9 percentages of protein, it was deemed advisable to calculate from Henry and Morrison's tables of composition for feedstuffs the amount of protein required to produce each pound of gain made by the male and female turkeys. Table 4 shows the results obtained. This table indicates that required less protein for each pound of gain in weight than do the. In one lot there was no difference but three lots showed differences of 16, 17, and 24 percent favoring the. These differences were highly significant for the period 17 to 30, and also when the gains made by the from 17 to 2 were compared to gains made by from 17 to 26, the differences were statistically significant. Table S shows that from the seventeenth to thirtieth male turkeys also utilized the carbonaceous portion of their ration more efficiently than did the. The differences for the four lots compared in were 13, 17, 23, and 26 percent, in favor of the. These differences were highly significant. PROPORTION OF MASH AND GRAIN CONSUMED BY MALE AND FEMALE TURKEYS Female turkeys consumed a larger pro- 16 2o WEEKS FIG. 3. The relative rate of growth of male and female Bronze turkeys and the relative efficiency of gains made by the same and, AGE WEEKS FIG. 4. The rate of growth W 2 Wt X 100 V2 (W» + Wi) ) of male and female Bronze turkeys and the pounds of feed required by the same turkeys to produce a pound of gain, portion of grain than did the. Table and Figure 1 show the relative amounts of grain and mash consumed by male and female Bronze turkeys in As the birds became older they increased their grain consumption and reduced the relative amount of mash consumed. Table 9 and Figure 2 show the relative consumption of mixtures by male and female Bronze turkeys by two-week periods from the seventeenth to thirtieth in. It will be observed that in both years, during the later growing periods when grain was fed, the consumed a larger proportion of grain than did the. COST OF GAINS MADE BY MALE AND FEMALE TURKEYS The producer is interested in the monetary cost of producing turkeys. Therefore, the actual cost of gains made was calculated so the difference between and

8 10 E. M. FUNK could be noted. Table 6 shows the results obtained in. These costs vary with the efficiency of gains made and with the price of the feedstuffs used in making the gains. Gains made by the cost less than gains made by. The required less feed per pound of gain but the consumed less expensive feed (relatively more grain per pound of gain). The actual cost per pound of gain was, however, less for the., GREATER EFFICIENCY OF MALES RELATED TO A MORE RAPID GROWTH RATE An explanation for the greater efficiency of the male turkey in utilizing feed for increasing its body weight may be found in the fact that during the time the are making significantly more economical gains than the they are growing relatively more rapidly than the. Table 7 and Figure 3 show the relative growth rate and the relative efficiency of gains of the male and female Bronze turkeys raised in Figures 3 and 4 show the relation of the growth rate and the economy of gains made by male and female turkeys. It is evident from these charts that efficiency of gains and the rate of growth in turkeys are closely related. The cost of gains increases as the rate of growth slows down and since the female approches maturity at an earlier age than the male and her rate of growth slows down more rapidly than that of the male the gains made by the female become more expensive than the gains made by the male. SUMMARY Male Bronze turkeys produced more economical gains (pounds of feed per pound of gain) than. The difference was highly significant after the turkeys were 16 of age and increased with age. Male turkeys required less protein per pound of gain made from 17 to 30 than did the. They also required less protein per pound of gain to 2 of age than the required to 26 of age. Male turkeys also utilized carbonaceous material more efficiently than. Female turkeys consumed a higher proportion of grain than did the. The cost of gains in cents per pound was less with than with. Efficiency of gains in turkeys was closely related to rate of growth. grew at a more rapid rate than. REFERENCES Barrett, F. N., C. G. Card, and Ashley Berridge, Feeding and confinement rearing experiment with turkeys during Mich. Agr. Exp. Sta. Quarterly Bull. 23:2. Brooks, F. D., Influence of sex on utilization of feed in turkeys. Poultry Sci. : Harshaw, H. M., and R. R. Rector, The composition of turkeys as affected by age and sex. Poultry Sci. 19: Marsden, S. J., and J. Holmes Martin, Turkey Management. Interstate, Danville, 111. Pp. 70. Roberts, R. E., Levels of protein in rations for young turkeys. Purdue Agri. Exp. Sta. Bull. 44. Robertson, E. I., and J. S. Carver,. Concentrate feeding of turkeys. Wash. Agri. Exp. Sta. Bull Robertson, E. I., and L. A. Wilhelm. Concentrate Feeding of Broad-Breasted Bronze Turkeys. U. S. Egg and Poultry Magazine 46: , , October, 1940.