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Effect of Early Protein and Energy Restriction of Large Turkey Toms Fed High-Fat or Low-Fat Realimentation Diets.
Effect of Early Protein and Energy Restriction of Large Turkey Toms Fed High-Fat or Low-Fat Realimentation Diets. 1. Performance Characteristics 1 PETER R. FERKET2 and JERRY L. SELL Department of Animal Science, Iowa State University, Ames, Iowa 50011 (Received for publication November 6, 1989)
1990 Poultry Science 69:1974-1981 INTRODUCTION
Bohman (1955) defined compensatory growth as growth that is faster than normal after a period of nutrient restriction. This phenomenon has been observed with turkeys after moderate protein restriction during early development. Auckland et al. (1969) and Auckland and Morris (1971a,b) fed mediumsized turkey toms 70% of the protein required for maximum growth rate for the first 6 wk after hatch and found that subsequent body weight gain and feed efficiency were improved in comparison with full-fed controls. Johnson and Sell (1976) reported that large turkey toms fed diets containing 80 or 85% of the protein contained in the control diet from 10 days to 8 wk of age achieved body weights equal to those fed the control diet by 24 wk of age while consuming less feed. Moran (1981), Oju
1 Journal Paper Number J-12939 of the Iowa Agriculture and Home Economics Experiment Station, Ames, IA. Project Number 2577. 2 Address correspondence to P. R. Ferket, Department of Poultry Science, Norm Carolina State University, Raleigh, NC 27695-7608.
et al. (1988), and Hester et al. (1989) also have reported a compensatory growth response after mild dietary protein restriction. However, Ferket and Sell (1989) did not observe compensatory growth of large toms raised through 20 wk of age, regardless of the severity of early protein restriction. They postulated that compensatory growth in turkey toms most likely occurs late in the growth phase when the rate of body weight gain of unrestricted turkeys normally declines. In their comprehensive reviews on compensatory growth in animals, Wilson and Osbourn (1960) and Allden (1970) emphasized energy undernutrition and related compensatory growth to the amount of useful energy consumed. No information is available on the potential of restricting dietary energy alone or together with protein during early development on subsequent compensatory growth of turkeys. The quality of the realimentation diet may influence the degree of compensatory growth (Wilson and Osbourn, 1960; Auckland and Morris, 1971a,b). The improvements in feed efficiency observed during realimentation (Auckland et al., 1969; Auckland and Morris, 1971a,b; Auckland, 1972; Johnson and Sell,
1974
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ABSTRACT The effect of early protein and energy restriction on the performance of large turkey toms fed a high or low fat realimentation diet was studied. Two levels of protein [100% (HP) and 70% (LP) of 1984 National Research Council (NRC) recommendations] were available ad libitum in a factorial arrangement with two levels of energy [100% (HE) and 90% (LE) of 1984 NRC reference level] to Nicholas toms from 10 days to 6 wk of age. Subsequently, the four treatment groups were fed diets containing either 4 or 8% fat; other nutrients were kept consistent with 1984 NRC recommendations until the toms were 20 wk of age. The LP or LE diets reduced weight gain (WG) and increased feed:gain (F:G) ratio from 10 days to 6 wk of age (P<005). Feeding LP diets significantly reduced protein consumption per unit gain and increased energy consumption per unit per gain, but the converse was observed with LE. In contrast to toms fed the HP diets, those fed the LP diets from 6 to 20 wk of age were consistently lighter in 20-wk body weight (14.1 kg versus 14.6 kg, P<005) and had a lower F:G ratio (2.96 versus 3.04, P<005). Toms fed the LE diets were lighter than those fed HE diets until 18 wk (P<05), and they had a lower F:G ratio (2.97 versus 3.03, P<05) from 6 to 20 wk of age. Supplemental fat increased WG and decreased F:G ratio during realimentation, but interaction effects of fat with protein or energy were not observed. Toms responded more favorably to early protein than energy restriction, regardless of the fat content of the realimentation diet (Key wordy, turkeys, dietary protein, energy and fat, feed:gain ratio, compensatory growth)
EARLY NUTRITION OF TURKEY TOMS
1975
TABLE 1. Experimental design Restriction pericxr (10 days to 6 wk)
Realimentation period (6 to 20 wk)
Treatment1
n
Protein4
Energy4
n
Total dietary fat, %
HP-HE
8
100
100
HP-LE
8
100
90
LP-HE
8
70
100
LP-LE
8
70
90
4 4 4 4 4 4 4 4
4 8 4 8 4 8 4 1$
1976; Ferket and Sell, 1989; Hester et al, were provided with incandescent light for 24 1989) suggest that energy metabolism may h/day at 30 lx for the first 10 wk of age and at play a central role in the compensatory growth 15 lx thereafter. Room temperature was mainresponse. The degree of this response may be tained at 25 C from starting to 6 wk of age, 20 influenced by the energy density of the diet, C from 6 to 12 wk, and about 16 C thereafter. which is typically altered by adjusting the level Supplemental brooding heat was provided by of supplemental fat. The favorable effects of infrared lamps. The experiment was designed to have two supplemental dietary fat on feed efficiency and growth of turkeys has been well documented treatment periods: the restriction period from (Potter et al, 1974; Sell and Owings, 1981, 10 days to 6 wk of age and the realimentation period from 6 to 20 wk of age. During the 1984; Blair et al, 1989). The objectives of the experiment reported restriction period, poults were assigned to four herein were 1) to determine the effects of dietary treatments of eight replicate pens each (28 poults per pen). Dietary treatments consismoderate dietary protein and energy restriction ted of a factorial arrangement of diets containduring early development of turkey toms on ing two levels of dietary protein [100 or 70% subsequent weight gain and feed efficiency, of NRC (1984) recommendations for crude and 2) to determine the effect of energy protein] and two levels of energy [100 or 90% density (level of supplemental fat) of realimen- of NRC (1984) reference level for ME]. tation diets on performance of turkey toms Practical diets corresponding to these treatafter early protein and energy restriction. ments were formulated by using linear programming (Table 2). Proximate analysis was done on all feed ingredients to estimate MATERIALS AND METHODS protein, amino acid, and energy content to aid Large White Nicholas male poults were in diet formulation. Reduction of dietary raised to 10 days of age on a starter diet with protein and energy was attained by substituting nutrients formulated to conform to National wheat, barley, and oats for com, fat, and Research Council (NRC, 1984) reference lev- soybean meal so that essential amino acid els. At 10 days, the poults were weighed, content relative to protein remained similar to randomly distributed among 32 floor pens, and the respective control diets (HP-HE). All diets assigned to one of eight feed regimens as were available to the toms ad libitum in mash outlined in Table 1. The toms were housed in form. total confinement on wood shavings litter and During the realimentation period, each of given .32 m 2 of floor space per torn. Toms the four restriction period treatment groups
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1 HP-HE = high protein-high energy restriction period treatment; HP-LE = high protein-low energy restriction period treatment; LP-HE = low protein-high energy restriction period treatment; and LP-LE = low protein-low energy restriction period treatment 2 Eight pens (n) containing 28 toms per pen fed for ad libitum intake from 10 days to 6 wk of age. 3 Four pens (n) containing 25 toms per pen fed for ad libitum intake from 6 to 20 wk of age. Percentage of requirement for protein and energy as recommended by the National Research Council (1984).
1976
FERKET AND SELL TABLE 2. Composition of experimental rations^ fed to toms during the restriction period Grower I (3 to 6 wk)
Starter (10 days to 3 wk) Ingredient and analysis
HP-HE
HP-LE
LP-HE
LP-LE
3.50 5.90 30.00 7.29 4170
31.15 21.80 16.37 18.45
17.95 25.00 27.80 17.15
2.00 .19 .02 1.49 .37
2.00 .19 1.40 .40
2.00 .12 .22 1.19 .50
2.00 .14 .20 1.07 .49
2.83
2.77
2.85
2.85
39.55 4.20 44.00
HP-HE
HP-LE
LP-HE
LP-LE
12.48 10.00 20.00 9.46 35.97
48.19 10.00 12.30 17.73
9.79 20.00 30.00 14.72 13.60
2.00 .10 .12 1.00
2.00 .11 .11 1.40 .41
2.00 .05 22 .87 .50
2.00 .07 .27 .93 .52
1.92
2.81
2.89
2.85
49.67
39.94
to 100% 20.0 20.0 28.0 28.0 20.4 21.0 28.5 27.5 2,521 2,802 2,527 2,800 3.3 4.7 3.4 5.9 4.0 4.0 4.0 4.0 .76 1.04 1.05 .77 122 1.23 1.68 1.70
18.5 18.7 26.0 26.0 18.5 26.6 19.3 27.0 2,615 2,902 2,615 2,896 4.9 3.18 4.5 2.7 4.0 4.0 4.0 4.0 .65 .65 1.16 1.00 1.15 1.15 1.60 1.60
1 HP-HE = high protein-high energy restriction period treatment; HP-LE = high protein-low energy restriction period treatment; LP-HE = low protein-high energy restriction period treatment; and LP-LE = low protein-low energy restriction period treatment. 2 AV-Fat = animal-vegetable fat blend. 3 Menhaden fish meal (60%), 2.50%; dehydrated alfalfa meal (17%), 2.00%; 3-nitro-4-hydroxyphenylarsonic acid (10%), .05%; Furox-50 (Furazolidone), 2% in starter and .1% in grower, vitamin premix, .3%; and mineral premix, .3%. The vitamin and mineral premixes supplied the following per kilogram of complete feed: vitamin A, 5,000 IU; vitamin D3, 1,500 IU; vitamin E, 12 IU; vitamin B ^ , 11 (tg; menadione (menadione sodium bisulfite), 1.8 mg;riboflavin,2.7 mg; pantothenic acid, 7 mg; niacin, 75 mg; choline, 509 mg; folic acid, .55 mg; biotin, 75 ng; ethoxyquin, 45 mg; manganese (MnSC^-^O), 70 mg; zinc (ZnO), 40 mg; iron [Fe3(S04)2-7H20], 37 mg; copper (CUSO4), 6 mg; selenium (Na2Se03), .15 mg; iodized NaCL 2.60 g. 4 Crude protein determined using Kjeldahl method.
was divided and fed a diet containing either 4 companion paper (Ferket and Sell, 1990). or 8% total dietary fat, resulting in four Body weight and feed efficiency data obtained replicate pens (ca. 25 poults per pen) of eight from 10 days to 6 wk of age were evaluated feed regimens. The fatty acid composition of statistically by two-factor analysis of variance the fat used in the formulation (expressed as a to ascertain the main effects of dietary protein percentage of total methyl esters) was myristic, and energy levels. Data obtained from 6 to 20 .85; palmitic, 20.60; palmitoleic, 2.23; stearic, wk were evaluated by a three-factor analysis of 9.70; oleic, 31.37; linoleic, 28.24; linolenic, variance to ascertain the effects of the level of 3.74; and others, 3.27. These diets were fat in the realimentation diets and the carryformulated by keeping dietary protein similar over effects of early protein and energy but allowing dietary ME to increase as the nutrition. level of supplemental fat increased (Table 3). Body weight and feed consumption data RESULTS AND DISCUSSION were recorded at 3, 6, 8, 10, 12, 14, 16, 18, and20wkofageMortalitywasrecordedasit Restriction Period occurred. At 6,12, and 20 wk, three toms were randomly selected from each replicate pen for Poults fed the low-protein (LP) diets had carcass evaluation and the data reported in a about 18% lighter body weights at 6 wk of age
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Ground yellow corn Ground wheat Ground barley White oats Soybean meal (48% CP) Meat and bone meal (50% CP) DL-methionine L-lysine HC1 AV-fat2 Ground limestone Dicalcium phosphate (18.5% P) Constant3 Calculated analysis CP, % Calculated Determined ME, kcal/kg Crude fiber, % Ether extract, % TSAA, % Lysine, %
i
1977
EARLY NUTRITION OF TURKEY TOMS TABLE 3. Composition of experimental rations fed toms during the realimentation period Grower 2, 8 to 112 wk
Grower 1, 6 to 8 wk Ingredient and analysis
4% Fat !8% Fat
4% Fat 8% Fat 58.45 36.73 .04 .04 1.47 .95 1.72
4% Fat 8% Fat
Finisher, 16 to :20 wk 4% Fat 8% Fat
68.76 25.70 2.20
62.59 28.18 .94
75.14 19.69 2.00
70.20 20.63 1.95
.04 .05 .04 1.00 5.85 .75 1.07 .95 1.74 to 100%
.04
.01
.01
5.48 .87 1.30
176 .59 .71
5.16 .71 .74
52.83 37.73
22.3 22.2 23.1 23.6 3,210 3,021 2.63 2.71 8.1 4.7 .75 .75 1.30 1.30
19.0 19.0 19.5 19.3 3,300 3,110 2.60 2.50 4.2 8.0 .65 .65 1.04 1.01
16.5 16.5 16.5 16.8 3,370 3,200 2.40 2.48 4.5 7.7 .55 .55 .84 .83
'AV-Fat = animal-vegetable fat blend. Vitamin premix, .3%; mineral premix, .3%. The vitamin and mineral premixes supplied the following per kilogram of complete feed: vitamin A, 5,000 IU; vitamin D 3 ,1,500 IU; vitamin E, 12IU; vitamin B 1 2 ,11 |Xg; menadione, 1.8 mg; riboflavin, 27 mg; pantothenic acid, 7 mg; niacin, 75 mg; choline, 509 mg; folic acid, .55 mg; biotin, 75 |ig; ethoxyquin, 45 mg; manganese (M11SO4H2O), 70 mg; zinc (ZnO), 40 mg; iron [Fe3(S04)2-7H20], 37 mg; copper (CuSO^), 6 mg; selenium (Na2Se03), .15 mg; iodized NaCl, 2.60 g. 3 Crude protein determined using Kjeldahl method.
and consumed about 9% less feed than those fed the high-protein (HP) diets (Table 4). Feed consumed per gain in body weight increased in groups fed the LP diets. Consequently, the LP diet led to a 10% increase in energy intake per unit body weight gain and about a 21% reduction in the amount of protein consumed per body weight gain. These results agree with those reported by Ferket and Sell (1989). Poults fed me low-energy (LE) diets weighed less at 6 wk of age and consumed significantly more feed than those fed the high-energy (HE) diets, but not enough to compensate for the energy deficiency (Table 4). As a result, nutrient utilization was significantly reduced in poults fed the LE diets, as indicated by significant increases in the amount of feed, protein, and energy consumed per unit weight gain. The significant protein x energy interaction effects on body weight, feed consumption, and ME consumed per unit body weight gain during the restriction period illustrate the close nutritional relationship between dietary protein and energy (Table 4). Body weights of poults fed HP
diets were more severely restricted by the LE diets than body weights of poults fed the LP diets. In contrast to the LP poults, the HP poults did not seem to consume enough of the LE diets to compensate for the energy required to efficiently utilize the dietary protein. Instead of increasing feed intake, the poults fed the HP diets seemed to catabolize excess dietary protein after the carbohydrate and fat were used to fulfill the energy needs for growth. However, when dietary protein and energy were both submarginal (as in the LP-LE diets), the poults increased feed intake to fulfill their energy needs. Realimentation Period Highly significant main treatment effects on performance were observed during the realimentation period (Table 5), but interaction effects were only observed during the early part of this period. Early protein restriction resulted in a significant reduction in body weight and feed: gain ratio through to 20 wk of age; however, its effect on significantly depressing feed consump-
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46.54 52.19 Ground yellow corn 36.55 37.90 Soybean meal (48% CP) 4.00 4.00 Meat and bone meal (50% CP) 2.00 2.00 Alfalfa meal (17% CP) .17 .17 DL-methionine L-lysine HC1 .30 .30 1.32 5.62 AV-fat1 .15 .15 Ground limestone 2.72 2.72 Dicalcium phosphate (18.5% P) 2 Constant Calculated analysis CP, % 25.0 25.0 Calculated 25.0 Determined 25.9 2,894 :3,112 ME, kcal/kg 3.17 3.10 Crude fiber, % 4.8 Ether extract, % 8.3 .92 .92 TSAA, % 1.63 1.65 Lysine, %
Developer, 12 to 16 wk
1978
FERKET AND SELL TABLE 4. Effect of protein or energy restriction or both on poult performance from 10 days to 6 wk of age1
Treatment1 HP-HE HP-LE LP-HE LP-LE Source of variation
Feed consumption2
(kg) 2.21 1.90 1.71 1.65
(kg) 3.26 3.28 2.89 3.06
*** *** *** £17
*** ** * .03
FiG3
Proteirugain4
ME:gain5
(kg/kg) (g/kg) (kcaVkg) 1.73 466.8 4,953 2.00 525.5 5,087 1.90 377.4 5,472 2.16 406.0 5,591 Significance _ _ _ ^ _ — _ _ ^ _ _ _ _ ^ _ *** *** NS .04
*** * NS 42
*** * * 43.3
Average of eight pens of 28 toms per pen. HP-HE = high protein-high energy restriction period treatment; HP-LE=high protein-low energy restriction period treatment; LP-HE = low protein-high energy restriction period treatment; and LP-LE = low protein-low energy restriction period treatment Feed consumed per torn. ^eed consumed per body weight gained. ^Protein consumed per body weight gained. 5 Metabolizable energy consumed per body weight gained. 6 SEM based on 21 df. *P<.05. **P<01. **P<005.
tion prevailed only until 16 wk of age. Early energy restriction also continued to have a significant carry-over effect on reduced body weight until 18 wk of age, but not at 20 wk. Feed consumption after early energy restriction was not significantly reduced except for the period from 16 to 18 wk. Fat supplementation to the realimentation diets resulted in a highly significant improvement in body weight and feed efficiency throughout the realimentation period (Table 5). Fat supplementation failed to reduce feed consumption significantly during the realimentation period except from 16 to 18 wk of age. These data support the contention that body weight and feed efficiency of turkeys improve significantly as the level of dietary fat increases (Jensen et ah, 1970; Potter et al, 1974; Sell and Owings, 1981, 1984). Feed efficiency was improved about 1.3% per 1% incremental increase of total dietary fat. This response to dietary fat was less than the response observed by Sell and Owings (1984), who reported a 3.6% improvement in feed efficiency per 1% fat included in diets of turkeys during the 12- to 20-wk age period. As reported by Sell and Owings (1984), the accumulated difference in
body weight and feed efficiency in favor of toms fed diets with 8% fat became more pronounced as the birds aged. Feed consumption was mostly unaffected by the level of dietary fat and energy density of the realimentation diet (Table 5). Consequently, the toms consumed more energy when the diets contained 8% added fat than when they contained 4% added fat. However, the absence of a significant interaction effect of fat level in the realimentation diet and early protein or energy nutrition indicated that energy consumption during the realimentation period did not influence the compensatory growth response of the toms. Thus, the absolute rate of gain in early protein-restricted or energy-restricted birds subsequently fed the 8% fat realimentation diet was not different from that of the nonrestricted birds fed the same realimentation diet Even so, the additional energy from the 8% fat realimentation diet was better than the 4% fat diet in helping the restricted turkeys quickly recover from early deficits in body weight. The carry-over effect of early protein nutrition on body weights prevailed throughout realimentation. The protein-restricted toms did not exhibit compensatory growth during reali-
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Protein (P) Energy (E) P x E SEM (21) 6
Body weight at 6 wk of age
4 8 4 8 4 8 4 8
HP-HE
*5 .14
*
***
***
***4 NS .08 .07
NS
***
*** ***
***
NS
*»*
14.4 14.9 14.5 14.7 14.0 14.6 13.7 14.3
20 (kg:
NS NS .10
NS
***
2.8 2.8 2.9 2.9
3.3 3.3 3.2 3.2
6 to 8
10 to 12
•NS NS .08
NS
***
NS NS .10
NS
*
5.30 5.41 5.40 4.22 5.24 4.06 5.22 4.01 5.30 4.00 5.12 3.91 3.82 4.97 Significance 4.08 4.22
8 to 10
NS NS .11
NS
*
6.09 5.98 5.97 5.89
6.12 6.18 6.19 6.23
12 to 14
Feed consumptio
SEM based on 21 df.
***P<005.
**P<01.
*P<05.
6
^Energy x fat interaction.
Protein x energy interaction.
F:G = feed consumed per weight gained through the respective interval.
3
HP-HE = high protein-high energy restriction period treatment; HP-LE = high protein-tow energy restriction period treatm treatment; and LP-LE = low protein-low energy restriction period treatment.
2
***
**
***
12.8 13.3 12.5 12.8 12.2 12.9 12.0 12.7
18
NS NS NS .13 .14 .13
***
NS .15
*
***
10.5 11.3 10.4 10.8
11.0 11.4 10.7 11.2
16
NS
***
9.1 9.6 9.0 9.4 8.7 9.1 8.8 9.0
7.2 7.8 7.1 7.3 6.8 7.4 7.1 7.0
•
14
12
***
4.7 5.0 4.6 4.9
5.3 5.6 5.1 5.2
10
***
3.1 32 3.0 3.2
3.6 3.8 3.3 3.5
8
Body weight
'Average of four pens of ca. 25 toms per pen.
Protein level (10 days to 6 wk) Energy level (10 days to 6 wk) Fat level (6 to 20 wk) Interactions SEM (21) 6
LP-LE
LP-HE
HP-LE
Dietary fat, % 6 to 20 wk
Treatment2 10 days to 6 wk
Weeks of age
TABLE 5. Effect of early protein or energy restriction or both on subsequent performance of to
rom http://ps.oxfordjournals.org/ at UNIVERSITY OF VIRGINIA on April 12, 2015
1980
FERKET AND SELL
600 ttt
>,
•3
a &
500-
eo
"-. fi o
400"
a
consu
t
•0 V 1> 1*.
300-
, 200
4
6
8
10
12
14
Mean body weight, kg FIGURE 1. Effect of early protein nutrition [100% and 70% of National Research Council (NRC, 1984) recommendations for protein from 10 days to 6 wk of age] on feed consumption in relation to body weight for the 6- to 20-wk period. The seven points on each line correspond to feed intake and mean body weight for the periods 6 to 8,8 to 10,10 to 12,12 to 14,14 to 16,16 to 18, and 18 to 20 wk. Vertical bars are standard errors.
mentation, as defined by having greater weight gains on an absolute basis than those fed at the higher protein level (Table 5). The LP toms required 4 more days to attain the same 20-wk body weight as the HP toms. This lack of a compensatory growth response may be related to physiological stage of maturity. Early maturing turkeys subjected to a similar degree of protein restriction during early development recover their body weight deficits by 20 wk of age (Auckland et al., 1969; Auckland and Morris, 1971a,b). However, late maturing turkeys do not demonstrate a classical compensatory growth response until after 20 wk of age (Auckland, 1972; Oju et al., 1988). The lack of compensatory growth in the research reported here seemed to be limited by feed consumption early in the realimentation period. Toms that were fed the LP diets continued to consume less feed during the first 10 wk of realimentation than those fed the HP diets. This reduced feed consumption was a function of body size, because early protein nutrition did not influence daily feed intake relative to body weight (Figure 1). Sheehy and Senior (1942) first proposed that growthrestricted animals have better feed conversion upon realimentation than normal animals because their maintenance requirements are lower. Brody (1945) related lower maintenance re-
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2
quirement to smaller metabolic body size (body weight 72 ). In contrast, Auckland et al. (1969) concluded that the major factor responsible for compensatory growth after protein restriction in medium-strain turkeys was the increase in feed consumption (or appetite) relative to body size. Several other species exhibit a significant increase in appetite during compensatory growth [Bohman (1955) with cattle; Harris etal. (1986) with rats; and Brody et al. (1980) with chickens]. Appetite has a strong influence on the growth rate of poultry (Marks, 1978, 1979). Possibly, large-strain turkeys have a lower degree of compensatory growm than medium strains after early protein restriction because their appetite reaches an upper limit at an earlier age. Like toms subjected to early protein restriction, those subjected to early energy restriction did not exhibit compensatory growth during realimentation (Table 5). Toms fed the LE diets from 10 days to 6 wk of age weighed significantly less at 8, 10, 16, and 18 wk than those fed the HE diets; however, these two groups gained the same weight from 6 to 20 wk of age (14.30 to 1.78 = 12.52 kg versus 14.48 to 1.96 = 12.52 kg; LE versus HE). Early energy restriction also did not significantly affect feed consumption during realimentation, except during the 16- to 18-wk period (P<05). Mortality was not significantly influenced by any of the dietary treatments; however, the LP toms appeared to be more alert and mobile than the HP toms. Early protein restriction has been shown to reduce the incidence of leg weakness (Ferket and Sell, 1989; Hester et al, 1989). hi the current study, leg conditions of HE and LE toms were not noticeably different. From a perspective of practical turkey production, early protein restriction is more favorable man early energy restriction because of lower diet costs during the restriction period, coupled with a greater improvement in feed efficiency upon realimentation. With the feed ingredient prices prevailing at the time of the present research, early protein restriction reduced total feed cost by 4.5% or $.01 per kilogram of live weight gain as compared with conventionally fed toms when the toms were raised to 20 wk of age. Total feed costs were also reduced slightly by early protein when calculated restriction at a common market weight. However, economic benefit would depend upon prevailing feed ingredient and turkey market conditions and likely will be greatest when the
EARLY NUTRITION OF TURKEY TOMS
cost of dietary protein is high relative to turkey market price. ACKNOWLEDGMENTS
REFERENCES Allden, W. G., 1970. The effects of nutritional deprivation on the subsequent productivity of sheep and cattle. Nutr. Abstr. Rev. 40:1167-1184. Auckland, J. N., 1972. Compensatory growth in turkeys: Practical implications and limitations. World's Poult. Sci. J. 28:291-300. Auckland, J. N., and T. R. Morris, 1971a. Compensatory growth in turkeys: Effect of undernutrition on subsequent protein requirements. Br. Poult Sci. 12: 42-48. Auckland, J. N., and T. R. Morris, 1971b. Compensatory growth after undernutrition in market turkeys: Effect of low protein feeding and realimentation on body composition. Br. Poult Sci. 12:137-150. Auckland, J. N., T. R. Morris, and R. C. Jennings, 1969. Compensatory growth after undernutrition in market turkeys. Br. Poult. Sci. 10:293-302. Blair, M. E., L. M. Potter, and R. M. Hulet, 1989. Effects of dietary protein and added fat on turkeys varying in strain, sex, and age. 1. Live characteristics. Poultry Sci. 68:278-286. Bohman, V. R., 1955. Compensatory growth of beef cattle. The effect of hay maturity. J. Anim. Sci. 14: 249-255. Brody, S., 1945. Basal energy and protein metabolism in relation to body weight in mature animals of different species. Pages 352-403 in: Bioenergetics and Growth. Reinhold, New York, NY. Brody, T., Y. Eitan, M. Soller, I. Nir, and Z. Nitsan, 1980. Compensatory growth and sexual maturity in broiler females reared under severe food restriction from day of hatching. Br. Poult Sci. 21:437-446. Ferket, P. R., and J. L. Sell, 1989. Effect of severity of
early protein restriction on large turkey toms. 1. Performance characteristics and leg weakness. Poultry Sci. 68:676-686. Ferket, P. R., and J. L. Sell, 1990. Effect of early protein and energy restriction on large turkey toms fed highfat or low-fat realimentation diets. 2. Carcass characteristics. Poultry Sci. 69:1982-1990. Harris, RB.S., T. R. Kasser, and R. J. Martin, 1986. Dynamics of recovery of body composition after overfeeding, food restriction or starvation of mature female rats. J. Nutr. 116:2536-2546. Hester, P. Y., K. K. Knieger, and M. E. Jackson, 1989. The influence of restrictive and compensatory growth on lameness and performance of commercial male turkeys. Poultry Sci. 68(Suppl. 1):66. (Abstr.) Jensen, L. S., G. W. Schumaier, and J. D. Latshaw, 1970. "Extra-caloric" effect of dietary fat for developing turkeys as influenced by calorie:protein ratio. Poultry Sci. 49:1697-1704. Johnson, R. L., and J. L. Sell, 1976. Compensatory growth: a new production concept? North Dakota Farm Res. 33:17-20. Marks, H. L., 1978. Long-term selection for four-week body weight in Japanese quail under different nutritional environments. Theor. Appl. Genet 52: 105-111. Marks, H. L., 1979. Growth rate and feed intake of selected and nonselected broiler. Growth 43:80-90. Moran, E. T., Jr., 1981. Early protein nutrition, compensatory growth, and carcass quality of broiler-type torn turkeys. Poultry Sci. 60:401-406. National Research Council, 1984. Nutrient requirements of poultry. 8th ed. National Academy of Science, Washington, DC. Oju, E. M., P. E. Waibel, and S. L. NolL 1988. Early protein undernutrition and subsequent realimentation in turkeys. 1. Effect on performance and body composition. Poultry Sci. 67:1750-1759. Potter, L. M., J. R. Shelton, and L. G. Melton, 1974. Zinc bacitracin and added fat in diets of growing turkeys. Poultry Sci. 53:2070-2081. Sell, J. L„ and W. J. Owings, 1981. Supplemental fat and metabolizable energy-to-nutrient ratios for growing turkeys. Poultry Sci. 60:2293-2305. Sell, J. L., and W. J. Owings, 1984. Influence of feeding supplemental fat by age sequence on the performance of growing turkeys. Poultry Sci. 63:1184-1189. Sheeny, E. J., and B. J. Senior, 1942. Storing cattle at different levels of nutrition. J. Dep. Agric. (Repub. Irel.) 39:245-262. Wilson, P. N., and D. F. Osbourn, 1960. Compensatory growth after undernutrition in mammals and birds. Biol. Rev. 35:324-363.
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The financial assistance provided by the Fats and Protein Research Foundation, Des Plaines, IL; Feed Energy, Inc., Des Moines, IA; and the Iowa Turkey Marketing Council is gratefully acknowledged. Technical help of S. E. Scheideler, F. Escribano, I. Zatari, R. Angel, B. Rahn, and the Iowa State University poultry farm staff is appreciated.
1981
1990 Poultry Science 69:1974-1981 INTRODUCTION
Bohman (1955) defined compensatory growth as growth that is faster than normal after a period of nutrient restriction. This phenomenon has been observed with turkeys after moderate protein restriction during early development. Auckland et al. (1969) and Auckland and Morris (1971a,b) fed mediumsized turkey toms 70% of the protein required for maximum growth rate for the first 6 wk after hatch and found that subsequent body weight gain and feed efficiency were improved in comparison with full-fed controls. Johnson and Sell (1976) reported that large turkey toms fed diets containing 80 or 85% of the protein contained in the control diet from 10 days to 8 wk of age achieved body weights equal to those fed the control diet by 24 wk of age while consuming less feed. Moran (1981), Oju
1 Journal Paper Number J-12939 of the Iowa Agriculture and Home Economics Experiment Station, Ames, IA. Project Number 2577. 2 Address correspondence to P. R. Ferket, Department of Poultry Science, Norm Carolina State University, Raleigh, NC 27695-7608.
et al. (1988), and Hester et al. (1989) also have reported a compensatory growth response after mild dietary protein restriction. However, Ferket and Sell (1989) did not observe compensatory growth of large toms raised through 20 wk of age, regardless of the severity of early protein restriction. They postulated that compensatory growth in turkey toms most likely occurs late in the growth phase when the rate of body weight gain of unrestricted turkeys normally declines. In their comprehensive reviews on compensatory growth in animals, Wilson and Osbourn (1960) and Allden (1970) emphasized energy undernutrition and related compensatory growth to the amount of useful energy consumed. No information is available on the potential of restricting dietary energy alone or together with protein during early development on subsequent compensatory growth of turkeys. The quality of the realimentation diet may influence the degree of compensatory growth (Wilson and Osbourn, 1960; Auckland and Morris, 1971a,b). The improvements in feed efficiency observed during realimentation (Auckland et al., 1969; Auckland and Morris, 1971a,b; Auckland, 1972; Johnson and Sell,
1974
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ABSTRACT The effect of early protein and energy restriction on the performance of large turkey toms fed a high or low fat realimentation diet was studied. Two levels of protein [100% (HP) and 70% (LP) of 1984 National Research Council (NRC) recommendations] were available ad libitum in a factorial arrangement with two levels of energy [100% (HE) and 90% (LE) of 1984 NRC reference level] to Nicholas toms from 10 days to 6 wk of age. Subsequently, the four treatment groups were fed diets containing either 4 or 8% fat; other nutrients were kept consistent with 1984 NRC recommendations until the toms were 20 wk of age. The LP or LE diets reduced weight gain (WG) and increased feed:gain (F:G) ratio from 10 days to 6 wk of age (P<005). Feeding LP diets significantly reduced protein consumption per unit gain and increased energy consumption per unit per gain, but the converse was observed with LE. In contrast to toms fed the HP diets, those fed the LP diets from 6 to 20 wk of age were consistently lighter in 20-wk body weight (14.1 kg versus 14.6 kg, P<005) and had a lower F:G ratio (2.96 versus 3.04, P<005). Toms fed the LE diets were lighter than those fed HE diets until 18 wk (P<05), and they had a lower F:G ratio (2.97 versus 3.03, P<05) from 6 to 20 wk of age. Supplemental fat increased WG and decreased F:G ratio during realimentation, but interaction effects of fat with protein or energy were not observed. Toms responded more favorably to early protein than energy restriction, regardless of the fat content of the realimentation diet (Key wordy, turkeys, dietary protein, energy and fat, feed:gain ratio, compensatory growth)
EARLY NUTRITION OF TURKEY TOMS
1975
TABLE 1. Experimental design Restriction pericxr (10 days to 6 wk)
Realimentation period (6 to 20 wk)
Treatment1
n
Protein4
Energy4
n
Total dietary fat, %
HP-HE
8
100
100
HP-LE
8
100
90
LP-HE
8
70
100
LP-LE
8
70
90
4 4 4 4 4 4 4 4
4 8 4 8 4 8 4 1$
1976; Ferket and Sell, 1989; Hester et al, were provided with incandescent light for 24 1989) suggest that energy metabolism may h/day at 30 lx for the first 10 wk of age and at play a central role in the compensatory growth 15 lx thereafter. Room temperature was mainresponse. The degree of this response may be tained at 25 C from starting to 6 wk of age, 20 influenced by the energy density of the diet, C from 6 to 12 wk, and about 16 C thereafter. which is typically altered by adjusting the level Supplemental brooding heat was provided by of supplemental fat. The favorable effects of infrared lamps. The experiment was designed to have two supplemental dietary fat on feed efficiency and growth of turkeys has been well documented treatment periods: the restriction period from (Potter et al, 1974; Sell and Owings, 1981, 10 days to 6 wk of age and the realimentation period from 6 to 20 wk of age. During the 1984; Blair et al, 1989). The objectives of the experiment reported restriction period, poults were assigned to four herein were 1) to determine the effects of dietary treatments of eight replicate pens each (28 poults per pen). Dietary treatments consismoderate dietary protein and energy restriction ted of a factorial arrangement of diets containduring early development of turkey toms on ing two levels of dietary protein [100 or 70% subsequent weight gain and feed efficiency, of NRC (1984) recommendations for crude and 2) to determine the effect of energy protein] and two levels of energy [100 or 90% density (level of supplemental fat) of realimen- of NRC (1984) reference level for ME]. tation diets on performance of turkey toms Practical diets corresponding to these treatafter early protein and energy restriction. ments were formulated by using linear programming (Table 2). Proximate analysis was done on all feed ingredients to estimate MATERIALS AND METHODS protein, amino acid, and energy content to aid Large White Nicholas male poults were in diet formulation. Reduction of dietary raised to 10 days of age on a starter diet with protein and energy was attained by substituting nutrients formulated to conform to National wheat, barley, and oats for com, fat, and Research Council (NRC, 1984) reference lev- soybean meal so that essential amino acid els. At 10 days, the poults were weighed, content relative to protein remained similar to randomly distributed among 32 floor pens, and the respective control diets (HP-HE). All diets assigned to one of eight feed regimens as were available to the toms ad libitum in mash outlined in Table 1. The toms were housed in form. total confinement on wood shavings litter and During the realimentation period, each of given .32 m 2 of floor space per torn. Toms the four restriction period treatment groups
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1 HP-HE = high protein-high energy restriction period treatment; HP-LE = high protein-low energy restriction period treatment; LP-HE = low protein-high energy restriction period treatment; and LP-LE = low protein-low energy restriction period treatment 2 Eight pens (n) containing 28 toms per pen fed for ad libitum intake from 10 days to 6 wk of age. 3 Four pens (n) containing 25 toms per pen fed for ad libitum intake from 6 to 20 wk of age. Percentage of requirement for protein and energy as recommended by the National Research Council (1984).
1976
FERKET AND SELL TABLE 2. Composition of experimental rations^ fed to toms during the restriction period Grower I (3 to 6 wk)
Starter (10 days to 3 wk) Ingredient and analysis
HP-HE
HP-LE
LP-HE
LP-LE
3.50 5.90 30.00 7.29 4170
31.15 21.80 16.37 18.45
17.95 25.00 27.80 17.15
2.00 .19 .02 1.49 .37
2.00 .19 1.40 .40
2.00 .12 .22 1.19 .50
2.00 .14 .20 1.07 .49
2.83
2.77
2.85
2.85
39.55 4.20 44.00
HP-HE
HP-LE
LP-HE
LP-LE
12.48 10.00 20.00 9.46 35.97
48.19 10.00 12.30 17.73
9.79 20.00 30.00 14.72 13.60
2.00 .10 .12 1.00
2.00 .11 .11 1.40 .41
2.00 .05 22 .87 .50
2.00 .07 .27 .93 .52
1.92
2.81
2.89
2.85
49.67
39.94
to 100% 20.0 20.0 28.0 28.0 20.4 21.0 28.5 27.5 2,521 2,802 2,527 2,800 3.3 4.7 3.4 5.9 4.0 4.0 4.0 4.0 .76 1.04 1.05 .77 122 1.23 1.68 1.70
18.5 18.7 26.0 26.0 18.5 26.6 19.3 27.0 2,615 2,902 2,615 2,896 4.9 3.18 4.5 2.7 4.0 4.0 4.0 4.0 .65 .65 1.16 1.00 1.15 1.15 1.60 1.60
1 HP-HE = high protein-high energy restriction period treatment; HP-LE = high protein-low energy restriction period treatment; LP-HE = low protein-high energy restriction period treatment; and LP-LE = low protein-low energy restriction period treatment. 2 AV-Fat = animal-vegetable fat blend. 3 Menhaden fish meal (60%), 2.50%; dehydrated alfalfa meal (17%), 2.00%; 3-nitro-4-hydroxyphenylarsonic acid (10%), .05%; Furox-50 (Furazolidone), 2% in starter and .1% in grower, vitamin premix, .3%; and mineral premix, .3%. The vitamin and mineral premixes supplied the following per kilogram of complete feed: vitamin A, 5,000 IU; vitamin D3, 1,500 IU; vitamin E, 12 IU; vitamin B ^ , 11 (tg; menadione (menadione sodium bisulfite), 1.8 mg;riboflavin,2.7 mg; pantothenic acid, 7 mg; niacin, 75 mg; choline, 509 mg; folic acid, .55 mg; biotin, 75 ng; ethoxyquin, 45 mg; manganese (MnSC^-^O), 70 mg; zinc (ZnO), 40 mg; iron [Fe3(S04)2-7H20], 37 mg; copper (CUSO4), 6 mg; selenium (Na2Se03), .15 mg; iodized NaCL 2.60 g. 4 Crude protein determined using Kjeldahl method.
was divided and fed a diet containing either 4 companion paper (Ferket and Sell, 1990). or 8% total dietary fat, resulting in four Body weight and feed efficiency data obtained replicate pens (ca. 25 poults per pen) of eight from 10 days to 6 wk of age were evaluated feed regimens. The fatty acid composition of statistically by two-factor analysis of variance the fat used in the formulation (expressed as a to ascertain the main effects of dietary protein percentage of total methyl esters) was myristic, and energy levels. Data obtained from 6 to 20 .85; palmitic, 20.60; palmitoleic, 2.23; stearic, wk were evaluated by a three-factor analysis of 9.70; oleic, 31.37; linoleic, 28.24; linolenic, variance to ascertain the effects of the level of 3.74; and others, 3.27. These diets were fat in the realimentation diets and the carryformulated by keeping dietary protein similar over effects of early protein and energy but allowing dietary ME to increase as the nutrition. level of supplemental fat increased (Table 3). Body weight and feed consumption data RESULTS AND DISCUSSION were recorded at 3, 6, 8, 10, 12, 14, 16, 18, and20wkofageMortalitywasrecordedasit Restriction Period occurred. At 6,12, and 20 wk, three toms were randomly selected from each replicate pen for Poults fed the low-protein (LP) diets had carcass evaluation and the data reported in a about 18% lighter body weights at 6 wk of age
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Ground yellow corn Ground wheat Ground barley White oats Soybean meal (48% CP) Meat and bone meal (50% CP) DL-methionine L-lysine HC1 AV-fat2 Ground limestone Dicalcium phosphate (18.5% P) Constant3 Calculated analysis CP, % Calculated Determined ME, kcal/kg Crude fiber, % Ether extract, % TSAA, % Lysine, %
i
1977
EARLY NUTRITION OF TURKEY TOMS TABLE 3. Composition of experimental rations fed toms during the realimentation period Grower 2, 8 to 112 wk
Grower 1, 6 to 8 wk Ingredient and analysis
4% Fat !8% Fat
4% Fat 8% Fat 58.45 36.73 .04 .04 1.47 .95 1.72
4% Fat 8% Fat
Finisher, 16 to :20 wk 4% Fat 8% Fat
68.76 25.70 2.20
62.59 28.18 .94
75.14 19.69 2.00
70.20 20.63 1.95
.04 .05 .04 1.00 5.85 .75 1.07 .95 1.74 to 100%
.04
.01
.01
5.48 .87 1.30
176 .59 .71
5.16 .71 .74
52.83 37.73
22.3 22.2 23.1 23.6 3,210 3,021 2.63 2.71 8.1 4.7 .75 .75 1.30 1.30
19.0 19.0 19.5 19.3 3,300 3,110 2.60 2.50 4.2 8.0 .65 .65 1.04 1.01
16.5 16.5 16.5 16.8 3,370 3,200 2.40 2.48 4.5 7.7 .55 .55 .84 .83
'AV-Fat = animal-vegetable fat blend. Vitamin premix, .3%; mineral premix, .3%. The vitamin and mineral premixes supplied the following per kilogram of complete feed: vitamin A, 5,000 IU; vitamin D 3 ,1,500 IU; vitamin E, 12IU; vitamin B 1 2 ,11 |Xg; menadione, 1.8 mg; riboflavin, 27 mg; pantothenic acid, 7 mg; niacin, 75 mg; choline, 509 mg; folic acid, .55 mg; biotin, 75 |ig; ethoxyquin, 45 mg; manganese (M11SO4H2O), 70 mg; zinc (ZnO), 40 mg; iron [Fe3(S04)2-7H20], 37 mg; copper (CuSO^), 6 mg; selenium (Na2Se03), .15 mg; iodized NaCl, 2.60 g. 3 Crude protein determined using Kjeldahl method.
and consumed about 9% less feed than those fed the high-protein (HP) diets (Table 4). Feed consumed per gain in body weight increased in groups fed the LP diets. Consequently, the LP diet led to a 10% increase in energy intake per unit body weight gain and about a 21% reduction in the amount of protein consumed per body weight gain. These results agree with those reported by Ferket and Sell (1989). Poults fed me low-energy (LE) diets weighed less at 6 wk of age and consumed significantly more feed than those fed the high-energy (HE) diets, but not enough to compensate for the energy deficiency (Table 4). As a result, nutrient utilization was significantly reduced in poults fed the LE diets, as indicated by significant increases in the amount of feed, protein, and energy consumed per unit weight gain. The significant protein x energy interaction effects on body weight, feed consumption, and ME consumed per unit body weight gain during the restriction period illustrate the close nutritional relationship between dietary protein and energy (Table 4). Body weights of poults fed HP
diets were more severely restricted by the LE diets than body weights of poults fed the LP diets. In contrast to the LP poults, the HP poults did not seem to consume enough of the LE diets to compensate for the energy required to efficiently utilize the dietary protein. Instead of increasing feed intake, the poults fed the HP diets seemed to catabolize excess dietary protein after the carbohydrate and fat were used to fulfill the energy needs for growth. However, when dietary protein and energy were both submarginal (as in the LP-LE diets), the poults increased feed intake to fulfill their energy needs. Realimentation Period Highly significant main treatment effects on performance were observed during the realimentation period (Table 5), but interaction effects were only observed during the early part of this period. Early protein restriction resulted in a significant reduction in body weight and feed: gain ratio through to 20 wk of age; however, its effect on significantly depressing feed consump-
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46.54 52.19 Ground yellow corn 36.55 37.90 Soybean meal (48% CP) 4.00 4.00 Meat and bone meal (50% CP) 2.00 2.00 Alfalfa meal (17% CP) .17 .17 DL-methionine L-lysine HC1 .30 .30 1.32 5.62 AV-fat1 .15 .15 Ground limestone 2.72 2.72 Dicalcium phosphate (18.5% P) 2 Constant Calculated analysis CP, % 25.0 25.0 Calculated 25.0 Determined 25.9 2,894 :3,112 ME, kcal/kg 3.17 3.10 Crude fiber, % 4.8 Ether extract, % 8.3 .92 .92 TSAA, % 1.63 1.65 Lysine, %
Developer, 12 to 16 wk
1978
FERKET AND SELL TABLE 4. Effect of protein or energy restriction or both on poult performance from 10 days to 6 wk of age1
Treatment1 HP-HE HP-LE LP-HE LP-LE Source of variation
Feed consumption2
(kg) 2.21 1.90 1.71 1.65
(kg) 3.26 3.28 2.89 3.06
*** *** *** £17
*** ** * .03
FiG3
Proteirugain4
ME:gain5
(kg/kg) (g/kg) (kcaVkg) 1.73 466.8 4,953 2.00 525.5 5,087 1.90 377.4 5,472 2.16 406.0 5,591 Significance _ _ _ ^ _ — _ _ ^ _ _ _ _ ^ _ *** *** NS .04
*** * NS 42
*** * * 43.3
Average of eight pens of 28 toms per pen. HP-HE = high protein-high energy restriction period treatment; HP-LE=high protein-low energy restriction period treatment; LP-HE = low protein-high energy restriction period treatment; and LP-LE = low protein-low energy restriction period treatment Feed consumed per torn. ^eed consumed per body weight gained. ^Protein consumed per body weight gained. 5 Metabolizable energy consumed per body weight gained. 6 SEM based on 21 df. *P<.05. **P<01. **P<005.
tion prevailed only until 16 wk of age. Early energy restriction also continued to have a significant carry-over effect on reduced body weight until 18 wk of age, but not at 20 wk. Feed consumption after early energy restriction was not significantly reduced except for the period from 16 to 18 wk. Fat supplementation to the realimentation diets resulted in a highly significant improvement in body weight and feed efficiency throughout the realimentation period (Table 5). Fat supplementation failed to reduce feed consumption significantly during the realimentation period except from 16 to 18 wk of age. These data support the contention that body weight and feed efficiency of turkeys improve significantly as the level of dietary fat increases (Jensen et ah, 1970; Potter et al, 1974; Sell and Owings, 1981, 1984). Feed efficiency was improved about 1.3% per 1% incremental increase of total dietary fat. This response to dietary fat was less than the response observed by Sell and Owings (1984), who reported a 3.6% improvement in feed efficiency per 1% fat included in diets of turkeys during the 12- to 20-wk age period. As reported by Sell and Owings (1984), the accumulated difference in
body weight and feed efficiency in favor of toms fed diets with 8% fat became more pronounced as the birds aged. Feed consumption was mostly unaffected by the level of dietary fat and energy density of the realimentation diet (Table 5). Consequently, the toms consumed more energy when the diets contained 8% added fat than when they contained 4% added fat. However, the absence of a significant interaction effect of fat level in the realimentation diet and early protein or energy nutrition indicated that energy consumption during the realimentation period did not influence the compensatory growth response of the toms. Thus, the absolute rate of gain in early protein-restricted or energy-restricted birds subsequently fed the 8% fat realimentation diet was not different from that of the nonrestricted birds fed the same realimentation diet Even so, the additional energy from the 8% fat realimentation diet was better than the 4% fat diet in helping the restricted turkeys quickly recover from early deficits in body weight. The carry-over effect of early protein nutrition on body weights prevailed throughout realimentation. The protein-restricted toms did not exhibit compensatory growth during reali-
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Protein (P) Energy (E) P x E SEM (21) 6
Body weight at 6 wk of age
4 8 4 8 4 8 4 8
HP-HE
*5 .14
*
***
***
***4 NS .08 .07
NS
***
*** ***
***
NS
*»*
14.4 14.9 14.5 14.7 14.0 14.6 13.7 14.3
20 (kg:
NS NS .10
NS
***
2.8 2.8 2.9 2.9
3.3 3.3 3.2 3.2
6 to 8
10 to 12
•NS NS .08
NS
***
NS NS .10
NS
*
5.30 5.41 5.40 4.22 5.24 4.06 5.22 4.01 5.30 4.00 5.12 3.91 3.82 4.97 Significance 4.08 4.22
8 to 10
NS NS .11
NS
*
6.09 5.98 5.97 5.89
6.12 6.18 6.19 6.23
12 to 14
Feed consumptio
SEM based on 21 df.
***P<005.
**P<01.
*P<05.
6
^Energy x fat interaction.
Protein x energy interaction.
F:G = feed consumed per weight gained through the respective interval.
3
HP-HE = high protein-high energy restriction period treatment; HP-LE = high protein-tow energy restriction period treatm treatment; and LP-LE = low protein-low energy restriction period treatment.
2
***
**
***
12.8 13.3 12.5 12.8 12.2 12.9 12.0 12.7
18
NS NS NS .13 .14 .13
***
NS .15
*
***
10.5 11.3 10.4 10.8
11.0 11.4 10.7 11.2
16
NS
***
9.1 9.6 9.0 9.4 8.7 9.1 8.8 9.0
7.2 7.8 7.1 7.3 6.8 7.4 7.1 7.0
•
14
12
***
4.7 5.0 4.6 4.9
5.3 5.6 5.1 5.2
10
***
3.1 32 3.0 3.2
3.6 3.8 3.3 3.5
8
Body weight
'Average of four pens of ca. 25 toms per pen.
Protein level (10 days to 6 wk) Energy level (10 days to 6 wk) Fat level (6 to 20 wk) Interactions SEM (21) 6
LP-LE
LP-HE
HP-LE
Dietary fat, % 6 to 20 wk
Treatment2 10 days to 6 wk
Weeks of age
TABLE 5. Effect of early protein or energy restriction or both on subsequent performance of to
rom http://ps.oxfordjournals.org/ at UNIVERSITY OF VIRGINIA on April 12, 2015
1980
FERKET AND SELL
600 ttt
>,
•3
a &
500-
eo
"-. fi o
400"
a
consu
t
•0 V 1> 1*.
300-
, 200
4
6
8
10
12
14
Mean body weight, kg FIGURE 1. Effect of early protein nutrition [100% and 70% of National Research Council (NRC, 1984) recommendations for protein from 10 days to 6 wk of age] on feed consumption in relation to body weight for the 6- to 20-wk period. The seven points on each line correspond to feed intake and mean body weight for the periods 6 to 8,8 to 10,10 to 12,12 to 14,14 to 16,16 to 18, and 18 to 20 wk. Vertical bars are standard errors.
mentation, as defined by having greater weight gains on an absolute basis than those fed at the higher protein level (Table 5). The LP toms required 4 more days to attain the same 20-wk body weight as the HP toms. This lack of a compensatory growth response may be related to physiological stage of maturity. Early maturing turkeys subjected to a similar degree of protein restriction during early development recover their body weight deficits by 20 wk of age (Auckland et al., 1969; Auckland and Morris, 1971a,b). However, late maturing turkeys do not demonstrate a classical compensatory growth response until after 20 wk of age (Auckland, 1972; Oju et al., 1988). The lack of compensatory growth in the research reported here seemed to be limited by feed consumption early in the realimentation period. Toms that were fed the LP diets continued to consume less feed during the first 10 wk of realimentation than those fed the HP diets. This reduced feed consumption was a function of body size, because early protein nutrition did not influence daily feed intake relative to body weight (Figure 1). Sheehy and Senior (1942) first proposed that growthrestricted animals have better feed conversion upon realimentation than normal animals because their maintenance requirements are lower. Brody (1945) related lower maintenance re-
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2
quirement to smaller metabolic body size (body weight 72 ). In contrast, Auckland et al. (1969) concluded that the major factor responsible for compensatory growth after protein restriction in medium-strain turkeys was the increase in feed consumption (or appetite) relative to body size. Several other species exhibit a significant increase in appetite during compensatory growth [Bohman (1955) with cattle; Harris etal. (1986) with rats; and Brody et al. (1980) with chickens]. Appetite has a strong influence on the growth rate of poultry (Marks, 1978, 1979). Possibly, large-strain turkeys have a lower degree of compensatory growm than medium strains after early protein restriction because their appetite reaches an upper limit at an earlier age. Like toms subjected to early protein restriction, those subjected to early energy restriction did not exhibit compensatory growth during realimentation (Table 5). Toms fed the LE diets from 10 days to 6 wk of age weighed significantly less at 8, 10, 16, and 18 wk than those fed the HE diets; however, these two groups gained the same weight from 6 to 20 wk of age (14.30 to 1.78 = 12.52 kg versus 14.48 to 1.96 = 12.52 kg; LE versus HE). Early energy restriction also did not significantly affect feed consumption during realimentation, except during the 16- to 18-wk period (P<05). Mortality was not significantly influenced by any of the dietary treatments; however, the LP toms appeared to be more alert and mobile than the HP toms. Early protein restriction has been shown to reduce the incidence of leg weakness (Ferket and Sell, 1989; Hester et al, 1989). hi the current study, leg conditions of HE and LE toms were not noticeably different. From a perspective of practical turkey production, early protein restriction is more favorable man early energy restriction because of lower diet costs during the restriction period, coupled with a greater improvement in feed efficiency upon realimentation. With the feed ingredient prices prevailing at the time of the present research, early protein restriction reduced total feed cost by 4.5% or $.01 per kilogram of live weight gain as compared with conventionally fed toms when the toms were raised to 20 wk of age. Total feed costs were also reduced slightly by early protein when calculated restriction at a common market weight. However, economic benefit would depend upon prevailing feed ingredient and turkey market conditions and likely will be greatest when the
EARLY NUTRITION OF TURKEY TOMS
cost of dietary protein is high relative to turkey market price. ACKNOWLEDGMENTS
REFERENCES Allden, W. G., 1970. The effects of nutritional deprivation on the subsequent productivity of sheep and cattle. Nutr. Abstr. Rev. 40:1167-1184. Auckland, J. N., 1972. Compensatory growth in turkeys: Practical implications and limitations. World's Poult. Sci. J. 28:291-300. Auckland, J. N., and T. R. Morris, 1971a. Compensatory growth in turkeys: Effect of undernutrition on subsequent protein requirements. Br. Poult Sci. 12: 42-48. Auckland, J. N., and T. R. Morris, 1971b. Compensatory growth after undernutrition in market turkeys: Effect of low protein feeding and realimentation on body composition. Br. Poult Sci. 12:137-150. Auckland, J. N., T. R. Morris, and R. C. Jennings, 1969. Compensatory growth after undernutrition in market turkeys. Br. Poult. Sci. 10:293-302. Blair, M. E., L. M. Potter, and R. M. Hulet, 1989. Effects of dietary protein and added fat on turkeys varying in strain, sex, and age. 1. Live characteristics. Poultry Sci. 68:278-286. Bohman, V. R., 1955. Compensatory growth of beef cattle. The effect of hay maturity. J. Anim. Sci. 14: 249-255. Brody, S., 1945. Basal energy and protein metabolism in relation to body weight in mature animals of different species. Pages 352-403 in: Bioenergetics and Growth. Reinhold, New York, NY. Brody, T., Y. Eitan, M. Soller, I. Nir, and Z. Nitsan, 1980. Compensatory growth and sexual maturity in broiler females reared under severe food restriction from day of hatching. Br. Poult Sci. 21:437-446. Ferket, P. R., and J. L. Sell, 1989. Effect of severity of
early protein restriction on large turkey toms. 1. Performance characteristics and leg weakness. Poultry Sci. 68:676-686. Ferket, P. R., and J. L. Sell, 1990. Effect of early protein and energy restriction on large turkey toms fed highfat or low-fat realimentation diets. 2. Carcass characteristics. Poultry Sci. 69:1982-1990. Harris, RB.S., T. R. Kasser, and R. J. Martin, 1986. Dynamics of recovery of body composition after overfeeding, food restriction or starvation of mature female rats. J. Nutr. 116:2536-2546. Hester, P. Y., K. K. Knieger, and M. E. Jackson, 1989. The influence of restrictive and compensatory growth on lameness and performance of commercial male turkeys. Poultry Sci. 68(Suppl. 1):66. (Abstr.) Jensen, L. S., G. W. Schumaier, and J. D. Latshaw, 1970. "Extra-caloric" effect of dietary fat for developing turkeys as influenced by calorie:protein ratio. Poultry Sci. 49:1697-1704. Johnson, R. L., and J. L. Sell, 1976. Compensatory growth: a new production concept? North Dakota Farm Res. 33:17-20. Marks, H. L., 1978. Long-term selection for four-week body weight in Japanese quail under different nutritional environments. Theor. Appl. Genet 52: 105-111. Marks, H. L., 1979. Growth rate and feed intake of selected and nonselected broiler. Growth 43:80-90. Moran, E. T., Jr., 1981. Early protein nutrition, compensatory growth, and carcass quality of broiler-type torn turkeys. Poultry Sci. 60:401-406. National Research Council, 1984. Nutrient requirements of poultry. 8th ed. National Academy of Science, Washington, DC. Oju, E. M., P. E. Waibel, and S. L. NolL 1988. Early protein undernutrition and subsequent realimentation in turkeys. 1. Effect on performance and body composition. Poultry Sci. 67:1750-1759. Potter, L. M., J. R. Shelton, and L. G. Melton, 1974. Zinc bacitracin and added fat in diets of growing turkeys. Poultry Sci. 53:2070-2081. Sell, J. L„ and W. J. Owings, 1981. Supplemental fat and metabolizable energy-to-nutrient ratios for growing turkeys. Poultry Sci. 60:2293-2305. Sell, J. L., and W. J. Owings, 1984. Influence of feeding supplemental fat by age sequence on the performance of growing turkeys. Poultry Sci. 63:1184-1189. Sheeny, E. J., and B. J. Senior, 1942. Storing cattle at different levels of nutrition. J. Dep. Agric. (Repub. Irel.) 39:245-262. Wilson, P. N., and D. F. Osbourn, 1960. Compensatory growth after undernutrition in mammals and birds. Biol. Rev. 35:324-363.
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The financial assistance provided by the Fats and Protein Research Foundation, Des Plaines, IL; Feed Energy, Inc., Des Moines, IA; and the Iowa Turkey Marketing Council is gratefully acknowledged. Technical help of S. E. Scheideler, F. Escribano, I. Zatari, R. Angel, B. Rahn, and the Iowa State University poultry farm staff is appreciated.
1981