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Growth and Performance of Broiler Breeders Fed Bacitracin Methylene Disalicylate and Zinc Bacitracin1
Growth and Performance of Broiler Breeders Fed Bacitracin Methylene Disalicylate and Zinc Bacitracin1
Department of Poultry Science, University of Florida, Gainesville, Florida 32611 R. V. FELL A. L. Laboratories, Inc., One Executive Drive, Fort Lee, New Jersey 07024 (Received for publication November 8, 1990) ABSTRACT Day-old Cobb broiler breeder pullets were randomly allotted into 20 floor pens where they were brooded and reared to 23 wk of age. Eight pens received a control diet containing no growth promotant The other 12 were fed 55 mg of bacitracin methylene disalicylate/kg of diet. Males were reared separately on the control diet Pallets were full-fed for the first 8 wk of life, men placed on a skip-a-day program with breederrecommended feed allocations. At 23 wk of age bird numbers were reduced to 26 females per pen, three males added, and diets changed to the layer regimen. Levels of 0,27.5,55, or 110 mg/kg of zinc bacitracin were each assigned to five pens with factorial attention to growing treatment Layer treatments were continued for 280 days. No significant differences were associated with the feeding of bacitracin methylene disalicylate among body weight or mortality data summarized at 8 and 23 wk. Eight-week feed efficiency was also not affected Jn the laying phase, 110 mg/kg of zinc bacitracin significantly improved egg production and fertility over the unsupplemented controls. Hatch of fertile eggs, overall hatchabiliry, and the number of chicks per pen were all significantly improved by 27.5 mg/kg of zinc bacitracin. Higher drug levels supported no additional improvement. Feed efficiency, mortality rate, andfinalbody weight were not significantly influenced by any level of supplementation. No effect of grower treatment upon subsequent layer performance was noted. (Key words: broiler breeders, bacitracin methylene disalicylate, zinc bacitracin, fertility, hatchabiliry) 1991 Poultry Science 70:1487-1492
in significant growth improvement in broilers Although the inclusion of feed additives in and poults. Neither egg production nor other broiler diets is a common procedure, the performance criteria of broiler breeder hens literature carries little recent information about were affected. These findings agree with those their use in broiler breeder diets. Carlson et al. of Damron and Harms (1972) where neither (1954) found egg production and hatchability moenomycin nor oxytetracycline influenced of fertile eggs from White Rock and New egg production, feed efficiency, daily feed Hampshire hens to be improved by supple- intake, body weight gains, mortality, egg ments of penicillin or streptomycin. Growth of weight, or hatch of fertile eggs. Percentage progeny from those hens to 4 wk of age was fertility was significantly reduced for groups somewhat impaired by penicillin and to a receiving either drug. lesser extent by streptomycin. Sherwood and Prasad et al. (1970) studied the maternal Milby (1954), working with White Leghorns, carryover effect of continuously feeding both White Rocks, and a "heavy cross-bred bird" neomycin sulfate and oxytetracycline throughgiven chlortetracycline, oxytetracycline, or out the laying cycle upon progeny performpenicillin, found no improvement of egg ance. Response in both trials, which involved production, feed efficiency, hatchability, or 15,000 broiler breeder hens, were positive. mortality. Improvements of broiler progeny performance Moneomycin, an unabsorbable antibiotic, were much greater than those noted for hens. was given to broilers, poults, and broiler The greatest enhancement was in feed effibreeder hens by Hazen et al. (1970), resulting ciency followed by growth, livability, and condemnations. The authors suggested that this response may have been related to improved taorida Agricultural Experiment Station Journal Series hatching egg quality. Number R-1138. INTRODUCTION
1487
Downloaded from https://academic.oup.com/ps/article-abstract/70/7/1487/1560025 by Iowa State University user on 23 January 2019
B. L. DAMRON and H. R. WILSON
1488
DAMRON EI AL.
MATERIALS AND METHODS
Seven hundred and twenty day-old Cobb broiler breeder pullet chicks were randomly distributed, 36 per pen, into each of 20 floor pens having 11.2 m* of floor area. Males were grown separately until the laying period. All birds received the following immunization regimen: aerosol vaccination for Newcastle disease and infectious bronchitis at 4 days, 5 wk, and 16 wk; fowl pox by wing-web at 1 and 8 wk; infectious bursal disease at 3 and 11 wk through drinking water, and avian encephalomyelitis in water at 11 wk. Due to a March starting time, the birds received increasing natural lighting through 20 wk of age. Wood shavings were used as floor covering and nesting material. During the 23-wk growing period the males and 8 pens of females were fed a control diet (Table 1) containing amprolium plus ethopabate as a coccidiostat, and 12 pens of females received a diet of identical nutrient concentration containing the above coccidiostat and 55 mg/kg of bacitracin methylene disalicylate. All birds were provided ad libitum access to feed until 8 wk of age when they were placed on a skip-a-day program. Birds were continued on full feed beyond the breeder-recommended age for
restriction because earlier work had shown some detrimental effect from early restriction (Wilson et al., 1972). Subsequent investigations by Wilson et al. (1989) have indicated that skip-a-day feeding started as early as 2 wk of age was not disadvantageous. Feed allocations were changed weekly according to the primary breeder's recommendations. Every 2 wk a different sample pen from each treatment of females was weighed so weight gains could be tracked through feed ration changes. Growing mortality was recorded daily and all pens of females were group weighed at 8 and 20 wk of age. Starting at 20 wk, 15 min of artificial light from incandescent bulbs was added weekly during the morning until a lighting period of 16 h (0430 to 2030 h) was achieved. At 23 wk all birds were individually weighed and a few of the lower-weight females removed until each pen contained 26 pullets. At this time the laying phase of the study was initiated along with four new treatments of 0, 27.5, 55, or 110 mg/kg of zinc bacitracin. There were five replicate pens for each treatment; two of these had been fed the control grower diet and three pens had previously received 55 mg/kg of bacitracin methylene disalicylate. The laying phase consisted of 10, 28-day periods. Three males were introduced into each pen, but replacements receiving a basal diet were held separately. Near the end of the second production period it became apparent that enough replacement males were not available for the entire length of the study, so one male was removed from each pen during the 1st wk of the third 28-day laying period and placed in the replacement pool. For the remainder of the trial male density was maintained at two per pen. Males were replaced only in the event of death or severe crippling. A 12-hole wall-hung nest box containing wood shavings was available in each pen and both floor and nests were dressed with fresh shavings as needed. Daily feed restriction was practiced using breeder-provided body weight standards as a guide coupled with biweekly check weighing of one pen receiving each treatment. A different replicate pen was weighed each period. Table 2 presents the composition of feeds that were developed according to the specifications of Harms and Wilson (1983) in order to maintain a uniform daily intake of nutrients other than energy. Feed selection was based on the dietary energy
Downloaded from https://academic.oup.com/ps/article-abstract/70/7/1487/1560025 by Iowa State University user on 23 January 2019
Damron and Wilson (1985) recorded a significant improvement in egg production and fertility as the result of adding 27.5 mg/kg or more of bacitracin methylene disalicylate to broiler breeder pullet diets during a 32-wk experiment. Hatchability of fertile eggs was not affected, but total hatchability was significantly improved in association with drug feeding, largely due to improved fertility. Body weights and mortality were not affected but egg weights were significantly lower for all drug levels. In a study closely paralleling the present one, Krueger et al. (1983) found a marked improvement in fertility and hatchability of total eggs in broiler breeders fed zinc bacitracin during the laying period. No differences in egg production, egg weight, or feed conversion were noted. Livability was improved by 4%. The current experiment was designed to further investigate zinc bacitracin's effects upon broiler breeder egg production and hatchability, and to identify any interactions with the use of bacitracin methylene disalicylate during the growing phase.
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BROILER BREEDERS FED BACITRACIN TABLE 1. Broiler breeder growing diets Ingredients and calculated composition
Weeks fed 0 to 5
6 to 8
9 to 10
11 to 12
13 to 14 15 to 16
17 to 18
19 to 23 88.73 8.40 .85 1.05 .40 .50
11.90 3,178 .62 .46 27 .24 .43 30 .14 .75 .18
(%) 75.42 21.10 1.40 1.05 .40 .50 .08
81.88 14.80 1.25 1.05 .40 JO .07
83.44 13.20 1.30 1.05 .40 .50 .06
83.82 13.15 1.00 1.05 .40 .50 .03
85.32 11.60 1.05 1.05 .40 30 .03
.05
.05
.05
.05
.05
87.18 10.00 .80 1.05 .40 30 .01 .01 .05
16.92 3,044 .82 .60 .39 .38 .65 .85 21 1.15 .18
14.42 3,107 .72 .55 .38 .34 .57 .67 .17 .95 .18
13.78 3,119 .73 36 .36 .32 .54 .62 .16 .90 .18
13.77 3,130 .67 .50 .30 .29 .51 .62 .16 .90 .18
13.15 3,142 .67 .51 .31 .28 .50 .57 .15 .85 .18
1234 3,165 .62 .46 26 26 .46 34 .15 .80 .18
.02 .05
Supplied the following activities per kilogram of diet vitamin A, 6,600 IU; vitamin D3, 2,200 ICU; menadione dimethylpyrimidinol bisulfite, 2.2 nog; riboflavin, 4.4 mg; pantothenic acid, 13.2 mg; niacin, 39.6 mg-, choline chloride, 499.4 mg; vitamin Bx2, 22 jig; ethoxyquin, 125 mg; manganese, 60 mg; iron, 50 mg; copper, 6 mg; cobalt, .198 mg; iodine, 1.1 mg; and zinc, 35 mg. ^National Research Council (1984).
concentration and intake required to continu- A completely randomized design was emally maintain a small rate of body weight gain. ployed in the growing and laying portions of Hen-day egg production, feed intake, and the study with separate analyses being permortality rate were recorded daily and used to formed on each data set Both growing and calculate egg production and feed efficiency laying treatments were assigned to pens at the summaries at the end of each 28-day period. In outset. An attempt was made to evaluate the all but the first period, fertility (all eggs hand interaction of growing and laying treatments, candled at 7 days of incubation), hatch of but data were variable and rarely significant, fertile eggs, overall hatchability, and the probably due to having only two measurecalculated possible number of chicks hatched ments for each interaction mean. The General per hen were determined. All eggs collected on Linear Models procedure was employed be5 consecutive days at the end of each record cause of unequal replication. period were incubated.2 During the 10th period, egg weight and specific gravity were RESULTS AND DISCUSSION measured on a 5-day collection of all eggs Body weights at 8, 20, or 23 wk of age produced. were not significantly influenced by the Data were statistically evaluated with feeding of 55 mg/kg of bacitracin methylene ANOVA and Duncan's multiple range test disalicylate (Table 3). Neither daily feed procedures using SAS® (SAS Institute, 1979). consumption nor feed efficiency was improved by bacitracin methylene disalicylate during the 8-wk brooding period. Mortality was not z Model 1H-A Robbins, Robbins Incubator Co., Den- related at any age to bacitracin methylene ver, CO 80239. disalicylate feeding.
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Yellow corn 71.99 Soybean meal (48.5% CP) 24.30 Dicalcium FO4 1.60 Limestone 1.05 Salt .40 1 Micro ingredients .50 DL-methionine .11 Lysine Coccidiostat .05 Calculated composition2 Crude protein, % 18.18 ME, kcal/kg 3,009 Calcium, % .82 Total P, % .65 Available P, % .43 Methionine, % .43 Sulfur amino acids, % .61 Lysine, % .95 Tryptophan, % .23 Arginine, % 1.25 Sodium, % .18
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DAMRON ET AL. TABLE 2. Broiler breeder layer diets that were assigned according to feed consumption
Ingredients and calculated composition
Daily feed per 100 birds (kg) 14.54
15.0
15.45
15.91
. (1i!\ i
76.52 14.89 1.19 6.66 .22 .50 .022 13.97 2,927 2.84 .53 .33 .28 .50 .66 .17 .93 .11
77.70 13.94 1.13 6.49 22 50 .015 13.61 2,944 2.76 .52 .32 XI .48 .63 .16 .90 .11
79.66 12.48 1.02 6.14 20 50
78.80 13.11 1.07 6.32 .20 .50 .001 13.29 2,959 2.68 .50 .31 .25 .47 .61 .16 .88 .10
13.06 2,973 2.60 .49 .30 25 .46 .59 .16 .86 .10
Supplied the following activities per kilogram of diet: vitamin A, 6,600 IU; vitamin D3, 2,200 ICU; menadione dimethylpyrimidinol bisulfite, 2.2 mg; riboflavin, 4.4 mg; pantothenic acid, 132 mg; niacin, 39.6 mg; choline chloride, 499.4 mg; vitamin Bj2, 22 (ig; ethoxyquin, 125 mg-, manganese, 60 mg; iron, 50 mg; copper, 6 mg; cobalt, .198 mg; iodine, 1.1 mg; and zinc, 35 mg. z National Research Council (1984).
TABLE 3. Treatment means for broiler breeders fed bacitracin methylene disalicylate during the growing period (0 to 23 wk)
Treatment
Body weight
Mortality rate
(mg/kg)
(%)
Daily feed1 intake
Feed:body weight1
(g)
(Pg)
85.9 85.8
2.19 2.18
8 wk Control 55 bacitracin methylene disalicylate SEM
1,904 1,910 97
Control 55 bacitracin methylene disalicylate SEM
2,128 2,134 65
Control 55 bacitracin methylene disalicylate SEM
2,434 2,438 83
1.39 1.16 ''O wk 2.08 3.94 23 wk 2.08 3.94
1 These parameters were measured only at 8 wk because a skip-a-day feeding program was initiated at that time and continued until the laying phase began.
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Yellow corn Soybean meal (48.5% CP) Dicalcium PO4 Limestone Salt Microingredients DL-methionine Calculated composition2 Crude protein, % ME, kcal/kg Calcium, % Total P, % Available P, % Methionine, % Sulfur amino acids, % Lysine, % Tryptophan, % Arginine, % Sodium, %
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BROILER BREEDERS FED BACITRACIN
TABLE 4. Performance of broiler breeders fed bacitracin methylene disalicylate during the growing phase or zinc bacitracin during the laying period (24 to 63 wk) or both
Hi
(mg/kg)
(%)
Final body weight
Layer mortality rate
(g)
(%)
4,090
4.33
133.7 86.12 81.78 4,046 rized by laying period treatment • 84.38b 79.17b 126.5b 4,081 93.50b 87.89* 82.93* 136.6* 4,096 93.62*b 86.69* 82.14* 133.0* 4,048 94.93"* 87.97* 84.01* 138.2* 4,030 95.47* .87 1.28 2.89 1.13
7.05
Fertility
59.88
3.43
93.91
60.88
3.38
94.70
Control 27.5 Zn bacitracin 55 Zn bacitracin 110 Zn bacitracin SEM
59.281b
3.44 3.45 3.41 3.32
a,b
60.04* 61.45* 1.94
Total hatch
Chicks per hen
f*M
(kg)
Control 55 bacitracin methylene disalicylate
eass *b
Hatch of fertile
marized by growing trc 133.4 87.66 8250
6.15 7.69 4.62 5.39
Means within a column with no common superscripts are significantly different (P<05).
The effects of bacitracin methylene disalicylate feeding during the growing period upon subsequent layer performance are summarized in Table 4. No differences were found for egg production, feed efficiency, egg fertility, fertile hatchability, total hatchability, or chicks per hen among treatment groups receiving either a control feed or one containing 55 mg/kg of bacitracin methylene disalicylate. Neither final body weight nor laying period mortality were significantly influenced by early bacitracin methylene disalicylate administration. Treatment during the laying phase with dietary zinc bacitracin resulted in a significant improvement of hen-day egg production at the 110 mg/kg level (Table 4). Feed efficiency was
not influenced by any level of the antibiotic. Fertility was significantly increased by 110 mg/kg of zinc bacitracin; however only 27.5 mg/kg was required to boost hatch of fertile eggs, total hatchability, and chicks per hen. Greater drug concentrations failed to produce additional improvement of the latter two parameters. Neither final body weights nor layer mortality were significantly altered by the use of zinc bacitracin. Egg weight and egg specific gravity data collected during the final production period did not reflect any effect of drug supplementation during either the growing or laying phase (Table 5). In the present experiment, the use of zinc bacitracin in broiler breeder laying diets was beneficial in terms of egg production, fertility,
TABLE 5. Tenth period egg weight and egg specific gravity data from broiler breeders fed bacitracin methylene disalicylate during the growing phase or zinc bacitracin during the laying period or both Treatment
Egg weight
(mg/kg)
(g)
Control 55 bacitracin methylene disalicylate
70.8 70.4
Control 27.5 Zn bacitracin 55 Zn bacitracin 110 Zn bacitracin
70.9 70.8 71.5 69.2
Egg specific gravity
— Summarized by growing treatment — 1.0775 1.0765 . Summarized by laying period treatment 1.0766 1.0770 1.0770 1.0769
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Treatment
Hen-day egg production
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DAMRON ET AL.
ACKNOWLEDGMENT
Appreciation is expressed to A. L. Laboratories, hie., Ft. Lee, NJ 07024 for the financial assistance and provision of drags that made this study possible. REFERENCES Carlson, C. W., D. G. Jones, R. A. Wilcox, and W. Kohlmeyer, 1952. Antibiotics in breeder diets. Poultry Sci. 31:910.(Abstr.) Damron, B. L., and R. H. Harms, 1972. The influence of monenomycin in the diets of broilers and leghorn and broiler breeder hens. Poultry Sci. 51:934-937. Damron, B. L., and H. R. Wilson, 1985. Bacitracin
methylene disalicylate in broiler breeder feeds. Poultry Sci. 64:1451-1454. Harms, R. H., and H. R. Wilson, 1983. Revised nutrient specifications for broiler breeder feeds given. FeedStuffs 55(4):71-72. Hazen, K. R., P. W. Waldroup, C. M. Hillard, R. J. Mitchell, and D. R. Sloan, 1970. Moneomycin—a new antibiotic for poultry feeds. Poultry Sci. 49: 1395.(Abstr.) Krueger, W. F., J. W. Bradley, and C. R. Creger, 1983. Effect of feeding Bacitracin Zn on reproduction in broiler breeders. Poultry Sci. 62:1450.(Abstr.) National Research Council, 1984. Nutrient Requirements of Poultry. 8th rev. ed. National Academy Press, Washington, DC. Prasad, S., E. G. Whitaker, and W. T. Hairr, 1970. Influence of antibiotics in the broiler breeder diet on progeny performance. Poultry Sci. 49:1428.(Abstr.) SAS Institute, 1979. SAS® User's Guide, 1979 Edition. SAS Institute, Inc., Raleigh, NC. Sherwood, D. H., and T. T. Milby, 1954. Further tests with antibiotics for laying and breeding hens. Poultry Sci. 33:1031-1033. Wilson, H. R., D. R. Ingram, F. B. Mather, and R. H. Harms, 1989. Effect of daily restriction and age at initiation of a skip-a-day program for young broiler breeders. Poultry Sci. 68:1442-1446. Wilson, H. R., R. A. Voitle, and R. H. Harms, 1972. Reproductive capacity of broiler males following protein restriction at various ages. Nutr. Rep. Int. 5: 9-15.
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hatch of fertile eggs, overall hatchability, and the number of chicks produced per hen. These data substantiate the work reported by Krueger et al. (1983) with zinc bacitracin and are similar to the report of Damron and Wilson (1985). Current results differ from these earlier studies in that egg production and hatch of fertile eggs were significantly improved in contrast to the results of Krueger et al. (1983) and Damron and Wilson (1985), respectively.
Department of Poultry Science, University of Florida, Gainesville, Florida 32611 R. V. FELL A. L. Laboratories, Inc., One Executive Drive, Fort Lee, New Jersey 07024 (Received for publication November 8, 1990) ABSTRACT Day-old Cobb broiler breeder pullets were randomly allotted into 20 floor pens where they were brooded and reared to 23 wk of age. Eight pens received a control diet containing no growth promotant The other 12 were fed 55 mg of bacitracin methylene disalicylate/kg of diet. Males were reared separately on the control diet Pallets were full-fed for the first 8 wk of life, men placed on a skip-a-day program with breederrecommended feed allocations. At 23 wk of age bird numbers were reduced to 26 females per pen, three males added, and diets changed to the layer regimen. Levels of 0,27.5,55, or 110 mg/kg of zinc bacitracin were each assigned to five pens with factorial attention to growing treatment Layer treatments were continued for 280 days. No significant differences were associated with the feeding of bacitracin methylene disalicylate among body weight or mortality data summarized at 8 and 23 wk. Eight-week feed efficiency was also not affected Jn the laying phase, 110 mg/kg of zinc bacitracin significantly improved egg production and fertility over the unsupplemented controls. Hatch of fertile eggs, overall hatchabiliry, and the number of chicks per pen were all significantly improved by 27.5 mg/kg of zinc bacitracin. Higher drug levels supported no additional improvement. Feed efficiency, mortality rate, andfinalbody weight were not significantly influenced by any level of supplementation. No effect of grower treatment upon subsequent layer performance was noted. (Key words: broiler breeders, bacitracin methylene disalicylate, zinc bacitracin, fertility, hatchabiliry) 1991 Poultry Science 70:1487-1492
in significant growth improvement in broilers Although the inclusion of feed additives in and poults. Neither egg production nor other broiler diets is a common procedure, the performance criteria of broiler breeder hens literature carries little recent information about were affected. These findings agree with those their use in broiler breeder diets. Carlson et al. of Damron and Harms (1972) where neither (1954) found egg production and hatchability moenomycin nor oxytetracycline influenced of fertile eggs from White Rock and New egg production, feed efficiency, daily feed Hampshire hens to be improved by supple- intake, body weight gains, mortality, egg ments of penicillin or streptomycin. Growth of weight, or hatch of fertile eggs. Percentage progeny from those hens to 4 wk of age was fertility was significantly reduced for groups somewhat impaired by penicillin and to a receiving either drug. lesser extent by streptomycin. Sherwood and Prasad et al. (1970) studied the maternal Milby (1954), working with White Leghorns, carryover effect of continuously feeding both White Rocks, and a "heavy cross-bred bird" neomycin sulfate and oxytetracycline throughgiven chlortetracycline, oxytetracycline, or out the laying cycle upon progeny performpenicillin, found no improvement of egg ance. Response in both trials, which involved production, feed efficiency, hatchability, or 15,000 broiler breeder hens, were positive. mortality. Improvements of broiler progeny performance Moneomycin, an unabsorbable antibiotic, were much greater than those noted for hens. was given to broilers, poults, and broiler The greatest enhancement was in feed effibreeder hens by Hazen et al. (1970), resulting ciency followed by growth, livability, and condemnations. The authors suggested that this response may have been related to improved taorida Agricultural Experiment Station Journal Series hatching egg quality. Number R-1138. INTRODUCTION
1487
Downloaded from https://academic.oup.com/ps/article-abstract/70/7/1487/1560025 by Iowa State University user on 23 January 2019
B. L. DAMRON and H. R. WILSON
1488
DAMRON EI AL.
MATERIALS AND METHODS
Seven hundred and twenty day-old Cobb broiler breeder pullet chicks were randomly distributed, 36 per pen, into each of 20 floor pens having 11.2 m* of floor area. Males were grown separately until the laying period. All birds received the following immunization regimen: aerosol vaccination for Newcastle disease and infectious bronchitis at 4 days, 5 wk, and 16 wk; fowl pox by wing-web at 1 and 8 wk; infectious bursal disease at 3 and 11 wk through drinking water, and avian encephalomyelitis in water at 11 wk. Due to a March starting time, the birds received increasing natural lighting through 20 wk of age. Wood shavings were used as floor covering and nesting material. During the 23-wk growing period the males and 8 pens of females were fed a control diet (Table 1) containing amprolium plus ethopabate as a coccidiostat, and 12 pens of females received a diet of identical nutrient concentration containing the above coccidiostat and 55 mg/kg of bacitracin methylene disalicylate. All birds were provided ad libitum access to feed until 8 wk of age when they were placed on a skip-a-day program. Birds were continued on full feed beyond the breeder-recommended age for
restriction because earlier work had shown some detrimental effect from early restriction (Wilson et al., 1972). Subsequent investigations by Wilson et al. (1989) have indicated that skip-a-day feeding started as early as 2 wk of age was not disadvantageous. Feed allocations were changed weekly according to the primary breeder's recommendations. Every 2 wk a different sample pen from each treatment of females was weighed so weight gains could be tracked through feed ration changes. Growing mortality was recorded daily and all pens of females were group weighed at 8 and 20 wk of age. Starting at 20 wk, 15 min of artificial light from incandescent bulbs was added weekly during the morning until a lighting period of 16 h (0430 to 2030 h) was achieved. At 23 wk all birds were individually weighed and a few of the lower-weight females removed until each pen contained 26 pullets. At this time the laying phase of the study was initiated along with four new treatments of 0, 27.5, 55, or 110 mg/kg of zinc bacitracin. There were five replicate pens for each treatment; two of these had been fed the control grower diet and three pens had previously received 55 mg/kg of bacitracin methylene disalicylate. The laying phase consisted of 10, 28-day periods. Three males were introduced into each pen, but replacements receiving a basal diet were held separately. Near the end of the second production period it became apparent that enough replacement males were not available for the entire length of the study, so one male was removed from each pen during the 1st wk of the third 28-day laying period and placed in the replacement pool. For the remainder of the trial male density was maintained at two per pen. Males were replaced only in the event of death or severe crippling. A 12-hole wall-hung nest box containing wood shavings was available in each pen and both floor and nests were dressed with fresh shavings as needed. Daily feed restriction was practiced using breeder-provided body weight standards as a guide coupled with biweekly check weighing of one pen receiving each treatment. A different replicate pen was weighed each period. Table 2 presents the composition of feeds that were developed according to the specifications of Harms and Wilson (1983) in order to maintain a uniform daily intake of nutrients other than energy. Feed selection was based on the dietary energy
Downloaded from https://academic.oup.com/ps/article-abstract/70/7/1487/1560025 by Iowa State University user on 23 January 2019
Damron and Wilson (1985) recorded a significant improvement in egg production and fertility as the result of adding 27.5 mg/kg or more of bacitracin methylene disalicylate to broiler breeder pullet diets during a 32-wk experiment. Hatchability of fertile eggs was not affected, but total hatchability was significantly improved in association with drug feeding, largely due to improved fertility. Body weights and mortality were not affected but egg weights were significantly lower for all drug levels. In a study closely paralleling the present one, Krueger et al. (1983) found a marked improvement in fertility and hatchability of total eggs in broiler breeders fed zinc bacitracin during the laying period. No differences in egg production, egg weight, or feed conversion were noted. Livability was improved by 4%. The current experiment was designed to further investigate zinc bacitracin's effects upon broiler breeder egg production and hatchability, and to identify any interactions with the use of bacitracin methylene disalicylate during the growing phase.
1489
BROILER BREEDERS FED BACITRACIN TABLE 1. Broiler breeder growing diets Ingredients and calculated composition
Weeks fed 0 to 5
6 to 8
9 to 10
11 to 12
13 to 14 15 to 16
17 to 18
19 to 23 88.73 8.40 .85 1.05 .40 .50
11.90 3,178 .62 .46 27 .24 .43 30 .14 .75 .18
(%) 75.42 21.10 1.40 1.05 .40 .50 .08
81.88 14.80 1.25 1.05 .40 JO .07
83.44 13.20 1.30 1.05 .40 .50 .06
83.82 13.15 1.00 1.05 .40 .50 .03
85.32 11.60 1.05 1.05 .40 30 .03
.05
.05
.05
.05
.05
87.18 10.00 .80 1.05 .40 30 .01 .01 .05
16.92 3,044 .82 .60 .39 .38 .65 .85 21 1.15 .18
14.42 3,107 .72 .55 .38 .34 .57 .67 .17 .95 .18
13.78 3,119 .73 36 .36 .32 .54 .62 .16 .90 .18
13.77 3,130 .67 .50 .30 .29 .51 .62 .16 .90 .18
13.15 3,142 .67 .51 .31 .28 .50 .57 .15 .85 .18
1234 3,165 .62 .46 26 26 .46 34 .15 .80 .18
.02 .05
Supplied the following activities per kilogram of diet vitamin A, 6,600 IU; vitamin D3, 2,200 ICU; menadione dimethylpyrimidinol bisulfite, 2.2 nog; riboflavin, 4.4 mg; pantothenic acid, 13.2 mg; niacin, 39.6 mg-, choline chloride, 499.4 mg; vitamin Bx2, 22 jig; ethoxyquin, 125 mg; manganese, 60 mg; iron, 50 mg; copper, 6 mg; cobalt, .198 mg; iodine, 1.1 mg; and zinc, 35 mg. ^National Research Council (1984).
concentration and intake required to continu- A completely randomized design was emally maintain a small rate of body weight gain. ployed in the growing and laying portions of Hen-day egg production, feed intake, and the study with separate analyses being permortality rate were recorded daily and used to formed on each data set Both growing and calculate egg production and feed efficiency laying treatments were assigned to pens at the summaries at the end of each 28-day period. In outset. An attempt was made to evaluate the all but the first period, fertility (all eggs hand interaction of growing and laying treatments, candled at 7 days of incubation), hatch of but data were variable and rarely significant, fertile eggs, overall hatchability, and the probably due to having only two measurecalculated possible number of chicks hatched ments for each interaction mean. The General per hen were determined. All eggs collected on Linear Models procedure was employed be5 consecutive days at the end of each record cause of unequal replication. period were incubated.2 During the 10th period, egg weight and specific gravity were RESULTS AND DISCUSSION measured on a 5-day collection of all eggs Body weights at 8, 20, or 23 wk of age produced. were not significantly influenced by the Data were statistically evaluated with feeding of 55 mg/kg of bacitracin methylene ANOVA and Duncan's multiple range test disalicylate (Table 3). Neither daily feed procedures using SAS® (SAS Institute, 1979). consumption nor feed efficiency was improved by bacitracin methylene disalicylate during the 8-wk brooding period. Mortality was not z Model 1H-A Robbins, Robbins Incubator Co., Den- related at any age to bacitracin methylene ver, CO 80239. disalicylate feeding.
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Yellow corn 71.99 Soybean meal (48.5% CP) 24.30 Dicalcium FO4 1.60 Limestone 1.05 Salt .40 1 Micro ingredients .50 DL-methionine .11 Lysine Coccidiostat .05 Calculated composition2 Crude protein, % 18.18 ME, kcal/kg 3,009 Calcium, % .82 Total P, % .65 Available P, % .43 Methionine, % .43 Sulfur amino acids, % .61 Lysine, % .95 Tryptophan, % .23 Arginine, % 1.25 Sodium, % .18
1490
DAMRON ET AL. TABLE 2. Broiler breeder layer diets that were assigned according to feed consumption
Ingredients and calculated composition
Daily feed per 100 birds (kg) 14.54
15.0
15.45
15.91
. (1i!\ i
76.52 14.89 1.19 6.66 .22 .50 .022 13.97 2,927 2.84 .53 .33 .28 .50 .66 .17 .93 .11
77.70 13.94 1.13 6.49 22 50 .015 13.61 2,944 2.76 .52 .32 XI .48 .63 .16 .90 .11
79.66 12.48 1.02 6.14 20 50
78.80 13.11 1.07 6.32 .20 .50 .001 13.29 2,959 2.68 .50 .31 .25 .47 .61 .16 .88 .10
13.06 2,973 2.60 .49 .30 25 .46 .59 .16 .86 .10
Supplied the following activities per kilogram of diet: vitamin A, 6,600 IU; vitamin D3, 2,200 ICU; menadione dimethylpyrimidinol bisulfite, 2.2 mg; riboflavin, 4.4 mg; pantothenic acid, 132 mg; niacin, 39.6 mg; choline chloride, 499.4 mg; vitamin Bj2, 22 (ig; ethoxyquin, 125 mg-, manganese, 60 mg; iron, 50 mg; copper, 6 mg; cobalt, .198 mg; iodine, 1.1 mg; and zinc, 35 mg. z National Research Council (1984).
TABLE 3. Treatment means for broiler breeders fed bacitracin methylene disalicylate during the growing period (0 to 23 wk)
Treatment
Body weight
Mortality rate
(mg/kg)
(%)
Daily feed1 intake
Feed:body weight1
(g)
(Pg)
85.9 85.8
2.19 2.18
8 wk Control 55 bacitracin methylene disalicylate SEM
1,904 1,910 97
Control 55 bacitracin methylene disalicylate SEM
2,128 2,134 65
Control 55 bacitracin methylene disalicylate SEM
2,434 2,438 83
1.39 1.16 ''O wk 2.08 3.94 23 wk 2.08 3.94
1 These parameters were measured only at 8 wk because a skip-a-day feeding program was initiated at that time and continued until the laying phase began.
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Yellow corn Soybean meal (48.5% CP) Dicalcium PO4 Limestone Salt Microingredients DL-methionine Calculated composition2 Crude protein, % ME, kcal/kg Calcium, % Total P, % Available P, % Methionine, % Sulfur amino acids, % Lysine, % Tryptophan, % Arginine, % Sodium, %
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BROILER BREEDERS FED BACITRACIN
TABLE 4. Performance of broiler breeders fed bacitracin methylene disalicylate during the growing phase or zinc bacitracin during the laying period (24 to 63 wk) or both
Hi
(mg/kg)
(%)
Final body weight
Layer mortality rate
(g)
(%)
4,090
4.33
133.7 86.12 81.78 4,046 rized by laying period treatment • 84.38b 79.17b 126.5b 4,081 93.50b 87.89* 82.93* 136.6* 4,096 93.62*b 86.69* 82.14* 133.0* 4,048 94.93"* 87.97* 84.01* 138.2* 4,030 95.47* .87 1.28 2.89 1.13
7.05
Fertility
59.88
3.43
93.91
60.88
3.38
94.70
Control 27.5 Zn bacitracin 55 Zn bacitracin 110 Zn bacitracin SEM
59.281b
3.44 3.45 3.41 3.32
a,b
60.04* 61.45* 1.94
Total hatch
Chicks per hen
f*M
(kg)
Control 55 bacitracin methylene disalicylate
eass *b
Hatch of fertile
marized by growing trc 133.4 87.66 8250
6.15 7.69 4.62 5.39
Means within a column with no common superscripts are significantly different (P<05).
The effects of bacitracin methylene disalicylate feeding during the growing period upon subsequent layer performance are summarized in Table 4. No differences were found for egg production, feed efficiency, egg fertility, fertile hatchability, total hatchability, or chicks per hen among treatment groups receiving either a control feed or one containing 55 mg/kg of bacitracin methylene disalicylate. Neither final body weight nor laying period mortality were significantly influenced by early bacitracin methylene disalicylate administration. Treatment during the laying phase with dietary zinc bacitracin resulted in a significant improvement of hen-day egg production at the 110 mg/kg level (Table 4). Feed efficiency was
not influenced by any level of the antibiotic. Fertility was significantly increased by 110 mg/kg of zinc bacitracin; however only 27.5 mg/kg was required to boost hatch of fertile eggs, total hatchability, and chicks per hen. Greater drug concentrations failed to produce additional improvement of the latter two parameters. Neither final body weights nor layer mortality were significantly altered by the use of zinc bacitracin. Egg weight and egg specific gravity data collected during the final production period did not reflect any effect of drug supplementation during either the growing or laying phase (Table 5). In the present experiment, the use of zinc bacitracin in broiler breeder laying diets was beneficial in terms of egg production, fertility,
TABLE 5. Tenth period egg weight and egg specific gravity data from broiler breeders fed bacitracin methylene disalicylate during the growing phase or zinc bacitracin during the laying period or both Treatment
Egg weight
(mg/kg)
(g)
Control 55 bacitracin methylene disalicylate
70.8 70.4
Control 27.5 Zn bacitracin 55 Zn bacitracin 110 Zn bacitracin
70.9 70.8 71.5 69.2
Egg specific gravity
— Summarized by growing treatment — 1.0775 1.0765 . Summarized by laying period treatment 1.0766 1.0770 1.0770 1.0769
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Treatment
Hen-day egg production
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DAMRON ET AL.
ACKNOWLEDGMENT
Appreciation is expressed to A. L. Laboratories, hie., Ft. Lee, NJ 07024 for the financial assistance and provision of drags that made this study possible. REFERENCES Carlson, C. W., D. G. Jones, R. A. Wilcox, and W. Kohlmeyer, 1952. Antibiotics in breeder diets. Poultry Sci. 31:910.(Abstr.) Damron, B. L., and R. H. Harms, 1972. The influence of monenomycin in the diets of broilers and leghorn and broiler breeder hens. Poultry Sci. 51:934-937. Damron, B. L., and H. R. Wilson, 1985. Bacitracin
methylene disalicylate in broiler breeder feeds. Poultry Sci. 64:1451-1454. Harms, R. H., and H. R. Wilson, 1983. Revised nutrient specifications for broiler breeder feeds given. FeedStuffs 55(4):71-72. Hazen, K. R., P. W. Waldroup, C. M. Hillard, R. J. Mitchell, and D. R. Sloan, 1970. Moneomycin—a new antibiotic for poultry feeds. Poultry Sci. 49: 1395.(Abstr.) Krueger, W. F., J. W. Bradley, and C. R. Creger, 1983. Effect of feeding Bacitracin Zn on reproduction in broiler breeders. Poultry Sci. 62:1450.(Abstr.) National Research Council, 1984. Nutrient Requirements of Poultry. 8th rev. ed. National Academy Press, Washington, DC. Prasad, S., E. G. Whitaker, and W. T. Hairr, 1970. Influence of antibiotics in the broiler breeder diet on progeny performance. Poultry Sci. 49:1428.(Abstr.) SAS Institute, 1979. SAS® User's Guide, 1979 Edition. SAS Institute, Inc., Raleigh, NC. Sherwood, D. H., and T. T. Milby, 1954. Further tests with antibiotics for laying and breeding hens. Poultry Sci. 33:1031-1033. Wilson, H. R., D. R. Ingram, F. B. Mather, and R. H. Harms, 1989. Effect of daily restriction and age at initiation of a skip-a-day program for young broiler breeders. Poultry Sci. 68:1442-1446. Wilson, H. R., R. A. Voitle, and R. H. Harms, 1972. Reproductive capacity of broiler males following protein restriction at various ages. Nutr. Rep. Int. 5: 9-15.
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hatch of fertile eggs, overall hatchability, and the number of chicks produced per hen. These data substantiate the work reported by Krueger et al. (1983) with zinc bacitracin and are similar to the report of Damron and Wilson (1985). Current results differ from these earlier studies in that egg production and hatch of fertile eggs were significantly improved in contrast to the results of Krueger et al. (1983) and Damron and Wilson (1985), respectively.