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Experimental Results in Fattening Chickens
POULTRY SCIENCE VOL. I I
April-May, 1923
No. 4
EXPERIMENTAL RESULTS IN FATTENING CHICKENS
T H E OBJECTS OP T H E EXPERIMENT
The fundamental objects of the experiment were to determine the most efficient practice in the fattening of chickens from the
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M. A. JULL AND W. A. MAW Department of Poultry Husbandry Macdonald College, P. Q. With the gradual development of the poultry industry there has resulted an increasing need for more knowledge concerning efficient methods of preparing poultry flesh for human consumption. Under existing conditions of food production it is imperative that every effort be made to produce stock of such good quality that there will be a minimum of waste. During recent years, however, so much attention has been given to the question of breeding for egg production, that it is quite possible that the best intesests of the fattening industry have been sacrificed to some extent at least. However impotant may be the matter of developing heavy laying strains there will always be a high proportion of chickens other than those used for breeding purposes and for which it is necessary to develop the most efficient means in preparing for market. Fattening is a finishing process designed to prepare chickens for human consumption in the most economical way. The main object in fattening is to improve the quality of the lean meat, the accumulation of fatty tissue as such being of secondary importance. When a chicken has been properly fattened, much of the water in the flesh is replaced by oil so that when the chicken is cooked the flesh becomes tender and juicy. Improvement in the quality of market chickens leads to increased consumption, which in turn leads to increased demands for prime fattened stock, thus creating a tendency for the greater improvement of the poultry industry.
102
POULTRY
SCIENCE
METHODS
All of the chickens used were of bred-to-lay strains of Barred Plymouth Eocks and Rhode Island Reds and particular care was exercised in the selection of stock suitable for fattening pur poses. Most of this work was conducted on the basis of lots con sisting of six chickens each. From the standopint of size two groups of chickens were used, a group of large-sized chickens approximating an average weight of four or more pounds each and a group of medium-sized chickens approximating an average weight of three or less pounds each. This division in weight seems justified in view of the possibility of marketing chickens when practically mature or about six weeks earlier in the season, when the market price for well fattened, dressed chickens is usually much higher. Both groups of chickens were fattened for ten day, two week and three week periods. The rations used are shown in tabular form, the figures repre senting parts by weight and the plus and minus signs indicating whether skim milk or water was used to moisten the ration.
1 Maw, W. Α., 1921, Experimental Results in Fattening Poultry, Jour. Amer. Inst, and Invest, in Poul. Husb., Vol. VII, No. 6.
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standpoint of size of stocky length of fattening period, and kind of ration. A solution of these problems would seem necessary before best results can be expected in commercial fattening work. With these objects in view, the Department of Poultry Husband ry of Macdonald College has been conducting, during the past seven years, a series of experiments in the fattening of chickens for market. A portion of the results have been discussed pre viously by the junior author,^ but in a different form than the complete results which are presented here. I t should be remarked that the actual fattening work was carried out almost exclusively by the junior author, and the fact that most of the work was done by one person doubtless has contributed much toward se curing uniform results.
FATTENING
CHICKENS
103
TABIJ; I — T H E RATIONS USED RATION
Oatmeal C'ornmeal . . Buckwheat. Middlings . Beef Scraps Milk Stock . S k i m milk . Water . . .
I
33.33 33.33 33.33 — — —
II
30.00 30.00 30.00 — 10.00 —
III
33.33 33.33 33.33 — — —
IV
30.00 30.00 30.00 — 10.00 —
V
26.66 26.66 26.66 — 20.00 —
VI
36.00 36.00 — 18.00 10.00 —
VII
VIII
32.00 32.00 — 16.00 20.00 —
36.00 36.00 — 18.00 5.00 5.00
- + + + ; + + + made + as—carefully - — - — + were as possible, the first
EESULTS
All of the results are expressed and discussed in terms of the number of pounds of each ration to produce one pound gain in flesh production. In making this determination for each ration the weight of milk used has not been taken into consideration because in those rations where milk was riot used the water used for each ration was not weighed. The weight of milk used in each ration is entered in the tables, however, first to show the amount of milk used and second to allow of financial calculations when such are desired. The financial aspects of this experiment as well as the chemical and nutritional problems involved are left for subsequent discussion.
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All weighings weighing being done on the morning of the day beginning the test and the final weighing being done approximately twelve hours after the final feeding. Fattening crates, each divided into three sections, were used and care was taken not to have the birds over-crowded. The chickens were fed three times daily, regularity always being kept in mind. During the first few days of each fattening period the amount of feed given was restricted but was increased gradually as the period advanced so that during the latter part of the period the chickens were given all they would eat. Bach feeding was prepared approximately twelve hours in advance of its being fed. In those rations in which milk was used, it was not made a definite percentage of the ration but only a sufficient quantity was weighed daily to make the ration of such a consistency as would allow of easy pouring from the feeding pail.
POULTRY
104
SCIENCE
TABLE I I — S H O W I N G T H E COMPARATIVE R E S U L T S BETWEEN LARGE-SIZED AND MEDIUM-SIZED C H I C K E N S FATTENED FOR T H R E E W E E K S
Group A—Average W e i g h t 4.44 Pounds Ration
Ν umber N u m l )er Birds Lois
Original Weight Pounds
Fattened Weight Pounds
Total Gain Pounds
Ration Consumed Pounds
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
III VI VII
36 30 21
6 5 3
162.75 135.25 88.50
210.25 177.44 116.37
47.50 42.19 27.87
215.50 195.25 133.00
325.25 255.74 170.49
4.53 4.62 4.77
Total
87
14
386.50
504.06
117.56
543.75
751.48
4.62
Group B -- A v e r a g e W e i g h t 3.06 Poundsi 64.74 9 262.00 345.00 172.51 237.25 142.25 87.50 75.50 19.25 3 56.25 18.25 141.00 3 59.25 77.50 85.00
4.04 4.54 4.66
III VI VII
58 18 18
390.25
102.24
434.50
628.25
4.25
TABLE III—SHOAVING T H E COMPARATIVE R E S U L T S BETWEEN LARGE-SIZED AND
MEDIUM-SIZED C H I C K E N S FATTENED FOR T W O W E E K S
Group A—Average W e i g h t 4.19 P o u n d s Ration Consumed Pounds
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
40.50 86.62 91.19
145.00 309.00 318.50
220.25 453.24 438.99
3.58 3.56 3.49
218.31
772.50
1112.48
3.53
Group B-—Average W e i g h t 2.87 Pounds 352.00 85.75 309.50 511.49 266.25 146.50 37.25 126.50 188.50 109.25 79.50 20.25 60.00 104.00 59.25
3.60 3.39 2.96
Number Number Ration Birds Lots
III
36 72 81
12 12
Total 189
30
VI VII
94 39 18
14 6 3
Total 151
23
III VI VII
Original Weight Pounds
Fattened Weight Pounds
162.75 297.25 332.75
203.25 383.87 423.94
792.75
1011.06
434.75
578.00
Total Gain Pounds
143.25
496.00
803.99
3.46
TABLE I V — S H O W I N G T H E COMPARATIVE R E S U L T S BETWEEN LARGE-SIZED AND MEDIUM-SIZED C H I C K E N S FATTENED FOR T E N D A Y S
Group A—Average Weight 4.41 P o u n d s
18 18 30
3 3 5
Total 66
11
III VI VII
III VI VII
18 36 30
3 6 5
Total 84
14
Original Weight Pounds
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
78.44 71.25 138.50
2.67 3.32 2.79
67.75 288.19 291.25 359.00 196.50 Group B -- A v e r a g e Weight 2.76 Pounds· 40.06 54.50 14.44 40.75 78.44 108.50 132.75 24.25 91.00 176.50 16.50 83.50 100.00, 56.50 116.50
2.90
Ν[umber Numb er Ration Birds Lots
66.75 85.75 138.75
232.06
Fattened Weight Pounds
86.75 103.75 168.50
287.25
Total Gain Pounds
20.00 18.00 29.75
55.19
Ration Consumed Pounds
53.50 59.75 83.25
188.25
371.44
2.82 3.75 3.42 4.41
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288.01
Total 94 15
FATTENING
CHICKENS
105
The proper length of time to fatten the two sizes of chickens is suggested by the results shown in Tables V and VI. I n Table V are shown the comparative results in fattening large-sized chickens for the three fattening periods with Rations III, VI, VII and VIII. It will be seen that for each ration the fewest pounds of grain to produce one pound gain in flesh were required
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The results dealing with the two sizes of chickens are presented first. I n Tables II, I I I and IV are shown the comparative results in the number of pounds of grain required to produce one pound gain in flesh production in large-sized and medium-sized chickens for the three fattening periods with Rations I I I , VI and VII. By comparing the results shown in Table II, where the chickens were fattened for three weeks, it will be seen that for each ration fewer pounds were required in the case of Group B, medium-sized chickens, than in the case of Group A, large-sized chickens. Also, for the group as a whole the mediumsized chickens required 4.24 pounds, while the large-sized chickens required 4.62 pounds. The results shown in Table III, where fattening was carried on for two weeks, show a slight tendency in favor of the medium-sized chickens. In Table IV, however, with a ten day fattening period, the results show that fewer pounds of grain are required to produce one pound gain in flesh production with large-sized than with medium-sized chickens. Each ration gave better results in Group A, than in Group B. and the rations taken together gave 2.90 pounds for the largesized chickens and 3.41 pounds for the medium-sized chickens. Taken all in all these results seem to show that for a ten day fattening period the large-sized chickens require fewer pounds of ration to produce one pound gain in flesh production but for the two and especially the three week periods the medium-sized chickens fatten with a lower ration consumption. In other words, it would seem that the size of the chickens determines, to some extent at least, the length of time they should be fattened.
POULTRY
106 TABLE V — S H O W I H G
THE
SCIENCE
COJIPARATIVE
RESUI^TS
IK
FATTENING
SIZED C H I C K E N S FOB T H R E E W E E K S , T W O W E E K S , AND T E N
LARGE-
DAYS
Group A—Average Weight 4.33 pounds T h r e e Weeks Ν umber Number Ration Birds Lots
III VI VII VIII
36 30 21 18
6 5 3 3
Total III VI VII VIII Total
Fattened Weight Pounds
162.75 135.25 88.50 68.25
210.25 177.44 116.37 92.00
Total Gain Pounds
47.50 42.19 27.87 23.75
Ration Consumed Pounds
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
215.50 195.25 133.00 110.00
325.25 255.74 170.49
4.53 4.62 4.77 4.63
596.06 653.75 751.48 454.75 141.31 Β—Average Weight 4.14 pounds Two Weeks 220.25 145.00 40.50 203.25 162.75 453.24 309.00 86.62 383.87 297.25 438.99 318.50 91.19 423.94 332.75 145.00 184.50 44.75 139.75
4.62 3.58 3.56 3.49 3.24
917.50 1112.48 225 36 263.06 932.50 1195.56 Gro up C—Average Weight 4.43 poundsi Ten Days 53,50 78.44 18 3 20.00 86.75 66.75 59.75 71.25 18 18.00 103.75 85.75 3 83.25 138.50 30 29.75 168.50 5 138.75 64.00 18 20.00 101.25 3 81,25 84 14
372.50
460.25
87.75
260.50
288.19
3.48 2.67 3.32 2.79 3.20 2.96
TABLE V I — S H O W I N G T H E COMPARATIVE R E S U L T S I N FATTENING MEDIUMSIZED C H I C K E N S FOR T H R E E W E E K S , T W O W E E K S , AND T E N
DAYS
Group A—Average Weight 3.14 pounds T h r e e Weeks Ration
Ν umber Number Birds Lots
III IV VI VII Total III IV VI VII
58 54 18 18
9 8 3 3
148 23 Group 94 14 90 14 39 6 18 3
Original Weight Pounds
Fattened Weight Pounds
172.51 177.75 56.25 59.25
237.25 250.30 75.50 77.50
Total Gain Pounds
64.74 72.55 19.25 18.25
Ration Consumed Ponuds
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
262.00 263.75 87.50 85.00
345.00 359.50 142.25 141.00
4.04 3.63 4.54 4.66
987.75 698.25 174.79 640.55 465.76 Β—Average Weight 2.95 pounds Two Weeks 352.00 85.75 511.49 266.25 309.50 379.25 276.50 102.75 292.50 523.87 188.50 146.50 37.25 126.50 109.25 79.50 20.25 59.25 60.00 104.00
3.99 3.60 2.84 3.39 2.96
957.25 246.00 711.25 788.50 1327.86 Total 241 37 Group C—Average Weight 2.76 pounds Ten Days 54.50 14.44 78.44 18 3 40.06 40.75 III 64.75 78.44 3 49.50 15.25 46.50 IV 18 132.75 24.25 91.00 176.50 36 6 108.50 VI 5 83.50 100.00 16.50 116.50 30 56.50 VII
2.82 3.05 3.75 3.42
Total
3.33
102 17
281.56
352.00
70.44
234.75
449.88
3.20
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Total 105 17 (Grroup 36 6 III 72 12 VI Λαι 81 12 36 6 VIII
Original Weight Pounds
FATTENING
CHICKENS
IQJ
The next step to consider is the relative efSciency of the var ious rations from the standpoint of the number of pounds of grain required to produce one pound gain in flesh. In this re spect it has been noted previously that both size of chicken and length of fattening period are factors which influence the situa tion, the factor of length of fattening period being relatively more significant than size of chicken. The results shown in Tables VII and VIII are compiled in such a way as to enable a comparison being made of the results obtained for the various rations fed to similar groups of chickens and for similar periods. Table VII shows the results secured with large-sized and med ium-sized chickens collectively for the three fattening periods, with the exception of Ration I, which was used for the two and three week periods only. Table VIII shows the results secured with medium-sized birds only for the three periods. Rations I I
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in Group C, the ten day fattening period, the next fewest in Group B, the two week fattening period, and consequently the most in Group A, the three week fattening period. Taking each, group as a whole, the same relation is borne out; Group G re quired only 2.96 pounds of ration to produce one pound gain in flesh production, Group Β required 3.48 pounds, and Group A, 4.62 pounds. These results confirm the suggestion previously made that large-sized birds should probably be fattened for about ten days. The results shown in Table VI, however, reveal a dif ferent situation. Here are shown the comparative results in fat tening medium-sized chickens for the three fattening periods with Rations III, IV, VI and VII. In this case, for each ration, except Ration III, the fewest pounds of grain to produce one pound of gain in flesh were required in Group B, the two week fattening period, the next fewest in Group C, the ten day fat tening period, and the most in Group A, the three week fatten ing period. Ration III proved to be an exception to the others,· inasmuch as it gave the best results for the ten day period. Tak ing each group as a whole, Group Β required only 3.20 pounds of grain to produce one pond gain in flesh production. Group C required 3.33 pounds and Group A, 3.99 pounds. These results are in conformity with the results secured previously and seem to show that medium-sized birds should be fattened for a period of two weeks.
108
POULTRY SOIENCE
a n d V not having been used for the ten d a y period. A l t h o u g h all the rations have not been used in the three fattening periods a n d for both sizes of chickens, still it is felt t h a t the results are sufficiently significant to w a r r a n t d r a w i n g certain conclusions. TABLE VII—SHOWUN-G THE COMPARATIVE RESULTS FKOM DIEFEHENT RATIONS WITH LABGE-SIZED AND MEDIUM-SIZED CHICKENS TAKE.N COIJ.ECTIVELY
Group A—Three Weeks Total Gain Pounds
Grain Consumed Pounds
Mill! Consumed Pounds
54.75 112.24 61.44 46.12
411.00 477.50 282.75 ' 218.00
670.25 397.99 311.49
7.51 4.25 4.60 4.73
Group Β — T W O Weeks 272.25 317.00 38.25 454.50 555.25 126.25 435.50 530.37 123.87 378.50 503.44 111.44
731.74 641.74 542.99
7.12 3.60 3.52 3.39
Group C—Ten Days 94.25 141.25 34.44 150.75 236.50 42.25 139.75 268,50 46.25
156.88 247.25 254.00
2.74 3.57 3.02
Fattened Weight Pounds
Original Weiglit Pounds
Number Birds
I III IV VII
08 94 48 39
276.75 335.26 191.50 147.75
333.50 447.50 252.94 193.87
I III VI VII
68 130 111 99
278.75 429.00 406.50 392.00
III VI VII
36 54 60
106.81 194.25 222.25
TABLE V I I I — S H O W ING
THE
COMPARATIVE
RESULTS
FROM
Lbs. of Grain to Produce 1 Pound Gain
DIFFERENT
R A T I O N S W I T H MEDIUM-SIZED C H I C K E N S
Group A—Three Weeks Mill< Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
Total Gain Pounds
G'a in Consumed Pounds
20.75 72.55 21.50
96.00 263.75 77.50
359.50 128.50
4.62 3.63 3.60
54.25 276.50 46.50
Group Β—Two Weeks 60.00 70.50 16.25 292.50 379.25 102.75 50.50 62.75 16.25
523.87 97.00
3.69 2.84 3.10
49.50
Group C—Ten Days 46.50 64.75 15.25
78.44
3.05
ο iginal Weight Pounds
F~attened Weight Pounds
Ration
Number Birds
II IV V
20 54 16
54.25 177.75 46.50
75.00 250.30 68.00
II IV V
20 90 16
IV
18
I n some respects t h e results shown in Table V I I a r e quite signiiieant. I t should be pointed out, for instance, t h a t the only difference between Rations I a n d I I I is t h a t Ration I was moist ened with water a n d Ration I I I was moistened with sour skim milk. The use of skim milk has reduced the n u m b e r of p o u n d s of grain required to produce one pound gain in flesh production
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Ration
FATTENING
CHICKENS
χ09
from 7.51 to 4.25 in the three week period and from 7.12 to 3.60 in the two week period. Ration I I I seems to have been most ef ficiently used in the ten day period, since only 2.74 pounds of grain were required while 3.60 pounds and 4.25 pounds were re quired for the two and three week periods, respectively. The chief difference between Rations VI and VII is that Ration VI contained ten and Ration VII twenty per cent beef scraps, but this difference did not produce a significant difference in the re sults secured. Ration VII gave slightly better results for the two shorter periods but slightly poorer results for the three week period.
TABLE IX—SHOAVIXG T H E COMPARATIVE RESTJLTS FEOM RA.TIOXS I, II, AND
IV
W I T H MEDIUM-SIZED
III,
CHICKESS
Group A—Three Weeks Original Weight Pounds
Ration
Number Birds
I II III IV
28 20 58 54
90.25 54.25 172.51 177.75
I II III IV
28 20 94 90
90.25 54.25 266.25 276.50
Fattened Weight Pounds
Tot.iI Gain Pounds
Grain Consumed Pounds
109.50 19.25 140.75 75.00 20.75 96.00 237.25 64.74 262.00 250.30 72.55 263.75 Group Β—Two Weeks 103.75 13.50 93.75 70.50 16.25 60.00 352.00 85.75 309.50 379.25 102.75 292.50
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
345.00 359.50
7.36 4.62 4.04 3.63
511.49 523.87
6.94 3.69 3.60 2.84
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The results shown in Table VIII are interesting, particularly from the standpoint of the results secured with Rations I I and IV. The only difference between these rations is that water was used with Ration II and sour skim milk with Ration IV, but the difference in the results secured is quite significant. In this case the use of skim milk reduced the number of pounds of grain re quired to produce one pound gain in flesh production from 4.62 to 3.63 in the three week period and from 3.69 to 2.84 in the two week period. The difference in the results secured with Rations IV and V is not significant, although Ration V contained twice as much beef scraps as Ration IV. These results are quite in harmony with those shown in Table VII and make it quite clear that the use of skim milk is necessary for best results in fattening and that where skim milk is not available fattening rations ap parently need not contain more than about ten per cent 'beef scraps.
]^-[0
POULTRY
SCIENCE
CONCLUSIONS
The size of chicken determines the most efficient length of fat tening period. Large-sized chickens, in bred-to-laj- strains of Barred Ply mouth Rocks and Rhode Island Reds, require a fattening period
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With these results in mind, it is well to compare the results se cured with Rations 1, II, III, and IV since Ration I consisted of a grain mixture plus water. Ration II consisted of the same grain mixture plus ten per cent beef scraps plus water. Ration I I I the same as No. I, except that skim milk Avas used instead of water. Ration ΙΛ^ the same as No. II, except tliat skim milk was used in stead of water. The results secured with medium-sized chickens are shown in Table IX. The value of skim milk in the ration is, again made evident by comparing the results of Rations I and III, 7.36 pounds as compared with 4.04 pounds in the three week period and 6.94 pounds as compared with 3.60 pounds in the tΛvo week period. The value of ten per cent beef scraps in the ration, where skim milk is not aA'ailable, is also made evident by comparing the results secured for Rations I and II, 7.36 pounds as compared with 4.62 pounds in the three week period and 6.94 pounds as compared with 3.69 pounds in the tAvo week period. When the results secured for Rations II and III are considered it is evi dent that skim milk gives slightly better results than ten per cent beef scraps. Then- by comparing the results secured for Rations I and IV it is apparent that the use of ten per cent beef scrap plus skim milk is justified, since the results are 7.36 pounds as compared with 3.63 pounds for the three week period and 6.94 pounds compared Λv^th 2.84 pounds for the two week period. But the significance of this difference disappears largely when the results secured for rations I I I and IV are compared. Ration IV gave somewhat better results but it is doubtful if the difference would justify the use of skim milk plus ten per cent expensive beef scraps. It is possible, however, that the use of a small per centage of beef scraps along with skim milk might be justified.
FATTENING
CHICKENS
m
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of about ten days, while medium-sized chickens require a fattening period of about two weeks. Where a mixture of two or more staple grains is used as a basal part of the ration, the use of sour skim milk, to moisten the ration, is necessary to produce the best results. Where sour skim milk is not available, the use of about ten per cent beef scraps seems justified. The use of twenty per cent beef scraps does not seem justified. Where sour skim milk is available, the use of ten per cent beef scraps does not seem justified, although it is possible that a smaller percentage might prove more efficient than sour skim milk alone. Under the conditions of this experiment, best results were secured in the following cases : with large-sized chickens fattened for ten days slightly less than three pounds of ration and with medium-sized chickens fattened for two weeks slightly more than three pounds of ration were required to produce one pound gain in flesh production.
April-May, 1923
No. 4
EXPERIMENTAL RESULTS IN FATTENING CHICKENS
T H E OBJECTS OP T H E EXPERIMENT
The fundamental objects of the experiment were to determine the most efficient practice in the fattening of chickens from the
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M. A. JULL AND W. A. MAW Department of Poultry Husbandry Macdonald College, P. Q. With the gradual development of the poultry industry there has resulted an increasing need for more knowledge concerning efficient methods of preparing poultry flesh for human consumption. Under existing conditions of food production it is imperative that every effort be made to produce stock of such good quality that there will be a minimum of waste. During recent years, however, so much attention has been given to the question of breeding for egg production, that it is quite possible that the best intesests of the fattening industry have been sacrificed to some extent at least. However impotant may be the matter of developing heavy laying strains there will always be a high proportion of chickens other than those used for breeding purposes and for which it is necessary to develop the most efficient means in preparing for market. Fattening is a finishing process designed to prepare chickens for human consumption in the most economical way. The main object in fattening is to improve the quality of the lean meat, the accumulation of fatty tissue as such being of secondary importance. When a chicken has been properly fattened, much of the water in the flesh is replaced by oil so that when the chicken is cooked the flesh becomes tender and juicy. Improvement in the quality of market chickens leads to increased consumption, which in turn leads to increased demands for prime fattened stock, thus creating a tendency for the greater improvement of the poultry industry.
102
POULTRY
SCIENCE
METHODS
All of the chickens used were of bred-to-lay strains of Barred Plymouth Eocks and Rhode Island Reds and particular care was exercised in the selection of stock suitable for fattening pur poses. Most of this work was conducted on the basis of lots con sisting of six chickens each. From the standopint of size two groups of chickens were used, a group of large-sized chickens approximating an average weight of four or more pounds each and a group of medium-sized chickens approximating an average weight of three or less pounds each. This division in weight seems justified in view of the possibility of marketing chickens when practically mature or about six weeks earlier in the season, when the market price for well fattened, dressed chickens is usually much higher. Both groups of chickens were fattened for ten day, two week and three week periods. The rations used are shown in tabular form, the figures repre senting parts by weight and the plus and minus signs indicating whether skim milk or water was used to moisten the ration.
1 Maw, W. Α., 1921, Experimental Results in Fattening Poultry, Jour. Amer. Inst, and Invest, in Poul. Husb., Vol. VII, No. 6.
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standpoint of size of stocky length of fattening period, and kind of ration. A solution of these problems would seem necessary before best results can be expected in commercial fattening work. With these objects in view, the Department of Poultry Husband ry of Macdonald College has been conducting, during the past seven years, a series of experiments in the fattening of chickens for market. A portion of the results have been discussed pre viously by the junior author,^ but in a different form than the complete results which are presented here. I t should be remarked that the actual fattening work was carried out almost exclusively by the junior author, and the fact that most of the work was done by one person doubtless has contributed much toward se curing uniform results.
FATTENING
CHICKENS
103
TABIJ; I — T H E RATIONS USED RATION
Oatmeal C'ornmeal . . Buckwheat. Middlings . Beef Scraps Milk Stock . S k i m milk . Water . . .
I
33.33 33.33 33.33 — — —
II
30.00 30.00 30.00 — 10.00 —
III
33.33 33.33 33.33 — — —
IV
30.00 30.00 30.00 — 10.00 —
V
26.66 26.66 26.66 — 20.00 —
VI
36.00 36.00 — 18.00 10.00 —
VII
VIII
32.00 32.00 — 16.00 20.00 —
36.00 36.00 — 18.00 5.00 5.00
- + + + ; + + + made + as—carefully - — - — + were as possible, the first
EESULTS
All of the results are expressed and discussed in terms of the number of pounds of each ration to produce one pound gain in flesh production. In making this determination for each ration the weight of milk used has not been taken into consideration because in those rations where milk was riot used the water used for each ration was not weighed. The weight of milk used in each ration is entered in the tables, however, first to show the amount of milk used and second to allow of financial calculations when such are desired. The financial aspects of this experiment as well as the chemical and nutritional problems involved are left for subsequent discussion.
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All weighings weighing being done on the morning of the day beginning the test and the final weighing being done approximately twelve hours after the final feeding. Fattening crates, each divided into three sections, were used and care was taken not to have the birds over-crowded. The chickens were fed three times daily, regularity always being kept in mind. During the first few days of each fattening period the amount of feed given was restricted but was increased gradually as the period advanced so that during the latter part of the period the chickens were given all they would eat. Bach feeding was prepared approximately twelve hours in advance of its being fed. In those rations in which milk was used, it was not made a definite percentage of the ration but only a sufficient quantity was weighed daily to make the ration of such a consistency as would allow of easy pouring from the feeding pail.
POULTRY
104
SCIENCE
TABLE I I — S H O W I N G T H E COMPARATIVE R E S U L T S BETWEEN LARGE-SIZED AND MEDIUM-SIZED C H I C K E N S FATTENED FOR T H R E E W E E K S
Group A—Average W e i g h t 4.44 Pounds Ration
Ν umber N u m l )er Birds Lois
Original Weight Pounds
Fattened Weight Pounds
Total Gain Pounds
Ration Consumed Pounds
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
III VI VII
36 30 21
6 5 3
162.75 135.25 88.50
210.25 177.44 116.37
47.50 42.19 27.87
215.50 195.25 133.00
325.25 255.74 170.49
4.53 4.62 4.77
Total
87
14
386.50
504.06
117.56
543.75
751.48
4.62
Group B -- A v e r a g e W e i g h t 3.06 Poundsi 64.74 9 262.00 345.00 172.51 237.25 142.25 87.50 75.50 19.25 3 56.25 18.25 141.00 3 59.25 77.50 85.00
4.04 4.54 4.66
III VI VII
58 18 18
390.25
102.24
434.50
628.25
4.25
TABLE III—SHOAVING T H E COMPARATIVE R E S U L T S BETWEEN LARGE-SIZED AND
MEDIUM-SIZED C H I C K E N S FATTENED FOR T W O W E E K S
Group A—Average W e i g h t 4.19 P o u n d s Ration Consumed Pounds
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
40.50 86.62 91.19
145.00 309.00 318.50
220.25 453.24 438.99
3.58 3.56 3.49
218.31
772.50
1112.48
3.53
Group B-—Average W e i g h t 2.87 Pounds 352.00 85.75 309.50 511.49 266.25 146.50 37.25 126.50 188.50 109.25 79.50 20.25 60.00 104.00 59.25
3.60 3.39 2.96
Number Number Ration Birds Lots
III
36 72 81
12 12
Total 189
30
VI VII
94 39 18
14 6 3
Total 151
23
III VI VII
Original Weight Pounds
Fattened Weight Pounds
162.75 297.25 332.75
203.25 383.87 423.94
792.75
1011.06
434.75
578.00
Total Gain Pounds
143.25
496.00
803.99
3.46
TABLE I V — S H O W I N G T H E COMPARATIVE R E S U L T S BETWEEN LARGE-SIZED AND MEDIUM-SIZED C H I C K E N S FATTENED FOR T E N D A Y S
Group A—Average Weight 4.41 P o u n d s
18 18 30
3 3 5
Total 66
11
III VI VII
III VI VII
18 36 30
3 6 5
Total 84
14
Original Weight Pounds
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
78.44 71.25 138.50
2.67 3.32 2.79
67.75 288.19 291.25 359.00 196.50 Group B -- A v e r a g e Weight 2.76 Pounds· 40.06 54.50 14.44 40.75 78.44 108.50 132.75 24.25 91.00 176.50 16.50 83.50 100.00, 56.50 116.50
2.90
Ν[umber Numb er Ration Birds Lots
66.75 85.75 138.75
232.06
Fattened Weight Pounds
86.75 103.75 168.50
287.25
Total Gain Pounds
20.00 18.00 29.75
55.19
Ration Consumed Pounds
53.50 59.75 83.25
188.25
371.44
2.82 3.75 3.42 4.41
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288.01
Total 94 15
FATTENING
CHICKENS
105
The proper length of time to fatten the two sizes of chickens is suggested by the results shown in Tables V and VI. I n Table V are shown the comparative results in fattening large-sized chickens for the three fattening periods with Rations III, VI, VII and VIII. It will be seen that for each ration the fewest pounds of grain to produce one pound gain in flesh were required
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The results dealing with the two sizes of chickens are presented first. I n Tables II, I I I and IV are shown the comparative results in the number of pounds of grain required to produce one pound gain in flesh production in large-sized and medium-sized chickens for the three fattening periods with Rations I I I , VI and VII. By comparing the results shown in Table II, where the chickens were fattened for three weeks, it will be seen that for each ration fewer pounds were required in the case of Group B, medium-sized chickens, than in the case of Group A, large-sized chickens. Also, for the group as a whole the mediumsized chickens required 4.24 pounds, while the large-sized chickens required 4.62 pounds. The results shown in Table III, where fattening was carried on for two weeks, show a slight tendency in favor of the medium-sized chickens. In Table IV, however, with a ten day fattening period, the results show that fewer pounds of grain are required to produce one pound gain in flesh production with large-sized than with medium-sized chickens. Each ration gave better results in Group A, than in Group B. and the rations taken together gave 2.90 pounds for the largesized chickens and 3.41 pounds for the medium-sized chickens. Taken all in all these results seem to show that for a ten day fattening period the large-sized chickens require fewer pounds of ration to produce one pound gain in flesh production but for the two and especially the three week periods the medium-sized chickens fatten with a lower ration consumption. In other words, it would seem that the size of the chickens determines, to some extent at least, the length of time they should be fattened.
POULTRY
106 TABLE V — S H O W I H G
THE
SCIENCE
COJIPARATIVE
RESUI^TS
IK
FATTENING
SIZED C H I C K E N S FOB T H R E E W E E K S , T W O W E E K S , AND T E N
LARGE-
DAYS
Group A—Average Weight 4.33 pounds T h r e e Weeks Ν umber Number Ration Birds Lots
III VI VII VIII
36 30 21 18
6 5 3 3
Total III VI VII VIII Total
Fattened Weight Pounds
162.75 135.25 88.50 68.25
210.25 177.44 116.37 92.00
Total Gain Pounds
47.50 42.19 27.87 23.75
Ration Consumed Pounds
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
215.50 195.25 133.00 110.00
325.25 255.74 170.49
4.53 4.62 4.77 4.63
596.06 653.75 751.48 454.75 141.31 Β—Average Weight 4.14 pounds Two Weeks 220.25 145.00 40.50 203.25 162.75 453.24 309.00 86.62 383.87 297.25 438.99 318.50 91.19 423.94 332.75 145.00 184.50 44.75 139.75
4.62 3.58 3.56 3.49 3.24
917.50 1112.48 225 36 263.06 932.50 1195.56 Gro up C—Average Weight 4.43 poundsi Ten Days 53,50 78.44 18 3 20.00 86.75 66.75 59.75 71.25 18 18.00 103.75 85.75 3 83.25 138.50 30 29.75 168.50 5 138.75 64.00 18 20.00 101.25 3 81,25 84 14
372.50
460.25
87.75
260.50
288.19
3.48 2.67 3.32 2.79 3.20 2.96
TABLE V I — S H O W I N G T H E COMPARATIVE R E S U L T S I N FATTENING MEDIUMSIZED C H I C K E N S FOR T H R E E W E E K S , T W O W E E K S , AND T E N
DAYS
Group A—Average Weight 3.14 pounds T h r e e Weeks Ration
Ν umber Number Birds Lots
III IV VI VII Total III IV VI VII
58 54 18 18
9 8 3 3
148 23 Group 94 14 90 14 39 6 18 3
Original Weight Pounds
Fattened Weight Pounds
172.51 177.75 56.25 59.25
237.25 250.30 75.50 77.50
Total Gain Pounds
64.74 72.55 19.25 18.25
Ration Consumed Ponuds
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
262.00 263.75 87.50 85.00
345.00 359.50 142.25 141.00
4.04 3.63 4.54 4.66
987.75 698.25 174.79 640.55 465.76 Β—Average Weight 2.95 pounds Two Weeks 352.00 85.75 511.49 266.25 309.50 379.25 276.50 102.75 292.50 523.87 188.50 146.50 37.25 126.50 109.25 79.50 20.25 59.25 60.00 104.00
3.99 3.60 2.84 3.39 2.96
957.25 246.00 711.25 788.50 1327.86 Total 241 37 Group C—Average Weight 2.76 pounds Ten Days 54.50 14.44 78.44 18 3 40.06 40.75 III 64.75 78.44 3 49.50 15.25 46.50 IV 18 132.75 24.25 91.00 176.50 36 6 108.50 VI 5 83.50 100.00 16.50 116.50 30 56.50 VII
2.82 3.05 3.75 3.42
Total
3.33
102 17
281.56
352.00
70.44
234.75
449.88
3.20
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Total 105 17 (Grroup 36 6 III 72 12 VI Λαι 81 12 36 6 VIII
Original Weight Pounds
FATTENING
CHICKENS
IQJ
The next step to consider is the relative efSciency of the var ious rations from the standpoint of the number of pounds of grain required to produce one pound gain in flesh. In this re spect it has been noted previously that both size of chicken and length of fattening period are factors which influence the situa tion, the factor of length of fattening period being relatively more significant than size of chicken. The results shown in Tables VII and VIII are compiled in such a way as to enable a comparison being made of the results obtained for the various rations fed to similar groups of chickens and for similar periods. Table VII shows the results secured with large-sized and med ium-sized chickens collectively for the three fattening periods, with the exception of Ration I, which was used for the two and three week periods only. Table VIII shows the results secured with medium-sized birds only for the three periods. Rations I I
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in Group C, the ten day fattening period, the next fewest in Group B, the two week fattening period, and consequently the most in Group A, the three week fattening period. Taking each, group as a whole, the same relation is borne out; Group G re quired only 2.96 pounds of ration to produce one pound gain in flesh production, Group Β required 3.48 pounds, and Group A, 4.62 pounds. These results confirm the suggestion previously made that large-sized birds should probably be fattened for about ten days. The results shown in Table VI, however, reveal a dif ferent situation. Here are shown the comparative results in fat tening medium-sized chickens for the three fattening periods with Rations III, IV, VI and VII. In this case, for each ration, except Ration III, the fewest pounds of grain to produce one pound of gain in flesh were required in Group B, the two week fattening period, the next fewest in Group C, the ten day fat tening period, and the most in Group A, the three week fatten ing period. Ration III proved to be an exception to the others,· inasmuch as it gave the best results for the ten day period. Tak ing each group as a whole, Group Β required only 3.20 pounds of grain to produce one pond gain in flesh production. Group C required 3.33 pounds and Group A, 3.99 pounds. These results are in conformity with the results secured previously and seem to show that medium-sized birds should be fattened for a period of two weeks.
108
POULTRY SOIENCE
a n d V not having been used for the ten d a y period. A l t h o u g h all the rations have not been used in the three fattening periods a n d for both sizes of chickens, still it is felt t h a t the results are sufficiently significant to w a r r a n t d r a w i n g certain conclusions. TABLE VII—SHOWUN-G THE COMPARATIVE RESULTS FKOM DIEFEHENT RATIONS WITH LABGE-SIZED AND MEDIUM-SIZED CHICKENS TAKE.N COIJ.ECTIVELY
Group A—Three Weeks Total Gain Pounds
Grain Consumed Pounds
Mill! Consumed Pounds
54.75 112.24 61.44 46.12
411.00 477.50 282.75 ' 218.00
670.25 397.99 311.49
7.51 4.25 4.60 4.73
Group Β — T W O Weeks 272.25 317.00 38.25 454.50 555.25 126.25 435.50 530.37 123.87 378.50 503.44 111.44
731.74 641.74 542.99
7.12 3.60 3.52 3.39
Group C—Ten Days 94.25 141.25 34.44 150.75 236.50 42.25 139.75 268,50 46.25
156.88 247.25 254.00
2.74 3.57 3.02
Fattened Weight Pounds
Original Weiglit Pounds
Number Birds
I III IV VII
08 94 48 39
276.75 335.26 191.50 147.75
333.50 447.50 252.94 193.87
I III VI VII
68 130 111 99
278.75 429.00 406.50 392.00
III VI VII
36 54 60
106.81 194.25 222.25
TABLE V I I I — S H O W ING
THE
COMPARATIVE
RESULTS
FROM
Lbs. of Grain to Produce 1 Pound Gain
DIFFERENT
R A T I O N S W I T H MEDIUM-SIZED C H I C K E N S
Group A—Three Weeks Mill< Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
Total Gain Pounds
G'a in Consumed Pounds
20.75 72.55 21.50
96.00 263.75 77.50
359.50 128.50
4.62 3.63 3.60
54.25 276.50 46.50
Group Β—Two Weeks 60.00 70.50 16.25 292.50 379.25 102.75 50.50 62.75 16.25
523.87 97.00
3.69 2.84 3.10
49.50
Group C—Ten Days 46.50 64.75 15.25
78.44
3.05
ο iginal Weight Pounds
F~attened Weight Pounds
Ration
Number Birds
II IV V
20 54 16
54.25 177.75 46.50
75.00 250.30 68.00
II IV V
20 90 16
IV
18
I n some respects t h e results shown in Table V I I a r e quite signiiieant. I t should be pointed out, for instance, t h a t the only difference between Rations I a n d I I I is t h a t Ration I was moist ened with water a n d Ration I I I was moistened with sour skim milk. The use of skim milk has reduced the n u m b e r of p o u n d s of grain required to produce one pound gain in flesh production
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Ration
FATTENING
CHICKENS
χ09
from 7.51 to 4.25 in the three week period and from 7.12 to 3.60 in the two week period. Ration I I I seems to have been most ef ficiently used in the ten day period, since only 2.74 pounds of grain were required while 3.60 pounds and 4.25 pounds were re quired for the two and three week periods, respectively. The chief difference between Rations VI and VII is that Ration VI contained ten and Ration VII twenty per cent beef scraps, but this difference did not produce a significant difference in the re sults secured. Ration VII gave slightly better results for the two shorter periods but slightly poorer results for the three week period.
TABLE IX—SHOAVIXG T H E COMPARATIVE RESTJLTS FEOM RA.TIOXS I, II, AND
IV
W I T H MEDIUM-SIZED
III,
CHICKESS
Group A—Three Weeks Original Weight Pounds
Ration
Number Birds
I II III IV
28 20 58 54
90.25 54.25 172.51 177.75
I II III IV
28 20 94 90
90.25 54.25 266.25 276.50
Fattened Weight Pounds
Tot.iI Gain Pounds
Grain Consumed Pounds
109.50 19.25 140.75 75.00 20.75 96.00 237.25 64.74 262.00 250.30 72.55 263.75 Group Β—Two Weeks 103.75 13.50 93.75 70.50 16.25 60.00 352.00 85.75 309.50 379.25 102.75 292.50
Milk Consumed Pounds
Lbs. of Grain to Produce 1 Pound Gain
345.00 359.50
7.36 4.62 4.04 3.63
511.49 523.87
6.94 3.69 3.60 2.84
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The results shown in Table VIII are interesting, particularly from the standpoint of the results secured with Rations I I and IV. The only difference between these rations is that water was used with Ration II and sour skim milk with Ration IV, but the difference in the results secured is quite significant. In this case the use of skim milk reduced the number of pounds of grain re quired to produce one pound gain in flesh production from 4.62 to 3.63 in the three week period and from 3.69 to 2.84 in the two week period. The difference in the results secured with Rations IV and V is not significant, although Ration V contained twice as much beef scraps as Ration IV. These results are quite in harmony with those shown in Table VII and make it quite clear that the use of skim milk is necessary for best results in fattening and that where skim milk is not available fattening rations ap parently need not contain more than about ten per cent 'beef scraps.
]^-[0
POULTRY
SCIENCE
CONCLUSIONS
The size of chicken determines the most efficient length of fat tening period. Large-sized chickens, in bred-to-laj- strains of Barred Ply mouth Rocks and Rhode Island Reds, require a fattening period
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With these results in mind, it is well to compare the results se cured with Rations 1, II, III, and IV since Ration I consisted of a grain mixture plus water. Ration II consisted of the same grain mixture plus ten per cent beef scraps plus water. Ration I I I the same as No. I, except that skim milk Avas used instead of water. Ration ΙΛ^ the same as No. II, except tliat skim milk was used in stead of water. The results secured with medium-sized chickens are shown in Table IX. The value of skim milk in the ration is, again made evident by comparing the results of Rations I and III, 7.36 pounds as compared with 4.04 pounds in the three week period and 6.94 pounds as compared with 3.60 pounds in the tΛvo week period. The value of ten per cent beef scraps in the ration, where skim milk is not aA'ailable, is also made evident by comparing the results secured for Rations I and II, 7.36 pounds as compared with 4.62 pounds in the three week period and 6.94 pounds as compared with 3.69 pounds in the tAvo week period. When the results secured for Rations II and III are considered it is evi dent that skim milk gives slightly better results than ten per cent beef scraps. Then- by comparing the results secured for Rations I and IV it is apparent that the use of ten per cent beef scrap plus skim milk is justified, since the results are 7.36 pounds as compared with 3.63 pounds for the three week period and 6.94 pounds compared Λv^th 2.84 pounds for the two week period. But the significance of this difference disappears largely when the results secured for rations I I I and IV are compared. Ration IV gave somewhat better results but it is doubtful if the difference would justify the use of skim milk plus ten per cent expensive beef scraps. It is possible, however, that the use of a small per centage of beef scraps along with skim milk might be justified.
FATTENING
CHICKENS
m
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of about ten days, while medium-sized chickens require a fattening period of about two weeks. Where a mixture of two or more staple grains is used as a basal part of the ration, the use of sour skim milk, to moisten the ration, is necessary to produce the best results. Where sour skim milk is not available, the use of about ten per cent beef scraps seems justified. The use of twenty per cent beef scraps does not seem justified. Where sour skim milk is available, the use of ten per cent beef scraps does not seem justified, although it is possible that a smaller percentage might prove more efficient than sour skim milk alone. Under the conditions of this experiment, best results were secured in the following cases : with large-sized chickens fattened for ten days slightly less than three pounds of ration and with medium-sized chickens fattened for two weeks slightly more than three pounds of ration were required to produce one pound gain in flesh production.