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Nutrient Requirements of Poultry: Ninth Revised Edition, 1994 5 Nutrient Requirements of Ducks Ducks can be grown successfully in either of two environments—an open rearing system, in which the growing house opens to an exercise yard with water for wading or swimming, or a confinement growing system, in which ducks are raised in environmentally controlled houses with litter or combination litter and wire floors. Pelleted diets are utilized more efficiently by ducks than are diets in mash form primarily because of reduced wastage and ease of consumption (Wilson, 1973; Dean, 1986). Starter diets (0 to 2 weeks) usually are fed as pellets of 3.18 mm (1/8 inch) diameter, and grower diets (after 2 weeks) are given in 4.76-mm (3/16 inch) form (Elkin, 1987). Ducks typically are given 2 or 3 feeds during the growing period. Information presented in Table 5-1 is on the basis of a two-feed program; a diet containing 22 percent protein for the period of 0 to 2 weeks and a 16 percent protein diet for the period from 2 to 7 weeks (Dean, 1972a, 1986). The need for 22 percent protein during the starting period, however, is questionable because Wilson (1975) and Siregar et al. (1982) reported that protein levels of 18 and 19 percent, respectively, in diets providing 3,000 to 3,025 kcal MEn/kg, were adequate from 0 to 2 weeks. A typical three-feed program may consist of diets containing 20, 18, and 16 percent protein for the periods from 0 to 2, 2 to 4, and 4 to 7 weeks, respectively. The growth rate of ducklings is not affected greatly by the MEn concentration of the diet; however, feed efficiency is usually improved and carcass fat increased when dietary MEn is increased (Wilson, 1975; Leclercq, 1986). Few data are available documenting the MEn values of feed ingredients for ducks. Mohamed et al. (1984) found that the MEn values of several feedstuffs were very similar for ducks and broiler chickens. Although most ducks grown commercially in the United States are White Pekins, considerable research TABLE 5-1 Nutrient Requirements of White Pekin Ducks as Percentages or Units per Kilogram of Diet (90 percent dry matter) Nutrient Unit 0 to 2 Weeks; 2,900a 2 to 7 Weeks; 3,000a Breeding; 2,900a Protein and amino acids Protein % 22 16 15 Arginine % 1.1 1.0 Isoleucine % 0.63 0.46 0.38 Leucine % 1.26 0.91 0.76 Lysine % 0.90 0.65 0.60 Methionine % 0.40 0.30 0.27 Methionine + cystine % 0.70 0.55 0.50 Tryptophan % 0.23 0.17 0.14 Valine % 0.78 0.56 0.47 Macrominerals Calcium % 0.65 0.60 2.75 Chloride % 0.12 0.12 0.12 Magnesium mg 500 500 500 Nonphytate phosphorus % 0.40 0.30 Sodium % 0.15 0.15 0.15 Trace minerals Manganese mg 50 ?b ? Selenium mg 0.20 ? ? Zinc mg 60 ? ? Fat soluble vitamins A IU 2,500 2,500 4,000 D3 IU 400 400 900 E IU 10 10 10 K mg 0.5 0.5 0.5 Water soluble vitamins Niacin mg 55 55 55 Pantothenic acid mg 11.0 11.0 11.0 Pyridoxine mg 2.5 2.5 3.0 Riboflavin mg 4.0 4.0 4.0 NOTE: For nutrients not listed or those for which no values are given, see requirements of broiler chickens (Table 2-5) as a guide. Where experimental data are lacking, values typeset in bold italics represent an estimate based on values obtained for other ages or species. a These are typical dietary energy concentrations as expressed in kcal MEn/kg diet. b Question marks indicate that no estimates are available.
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Nutrient Requirements of Poultry: Ninth Revised Edition, 1994 data obtained by using other breeds of ducks (that is, Muscovy and "mule" ducks) have been used to fill several voids in the requirement data of Table 5-1, especially with respect to amino acids and minerals. Published research reviewed in Appendix Table A-6 on lysine and total sulfur amino acid (TSAA) requirements indicates that values listed in the previous edition of this report were too high (Jeroch and Hennig, 1965; Dean, 1967; Gazo et al., 1970; Leclercq and de Carville, 1977a,b; Adams et al., 1983; Elkin et al. 1986). Adjustments were made accordingly. In addition, a tentative methionine requirement for starting ducks (0.40 percent) is given on the basis of data reported by Elkin et al. (1986). Noteworthy is information published recently by Elkin et al. (1988) showing that the relative value of the D-methionine isomer was 78 percent of that of the L-isomer. Consequently, in instances where supplemental methionine is needed in duck diets, adjustments may be needed in supplemental levels of the DL-methionine sources used. Only single papers have been published documenting the requirements of starting ducks for arginine, tryptophan, leucine, isoleucine, and valine (Chen and Shen, 1979; Wu et al., 1984; Yu and Shen, 1984). The values for these nutrients listed in Table 5-1 must therefore be viewed as tentative. The same is true of the requirement values for breeding ducks because relevant information is scarce (Cvetanov et al., 1969). Research to determine the mineral and vitamin requirements of ducks has focused primarily on the starting TABLE 5-2 Approximate Body Weights and Feed Consumption of White Pekin Ducks to 8 Weeks of Age Age (weeks) Body Weight (kg) Weekly Feed Consumption (kg) Cumulative Feed Consumption (kg) Male Female Male Female Male Female 0 0.06 0.06 0.00 0.00 0.00 0.00 1 0.27 0.27 0.22 0.22 0.22 0.22 2 0.78 0.74 0.77 0.73 0.99 0.95 3 1.38 1.28 1.12 1.11 2.11 2.05 4 1.96 1.82 1.28 1.28 3.40 3.33 5 2.49 2.30 1.48 1.43 4.87 4.76 6 2.96 2.73 1.63 1.59 6.50 6.35 7 3.34 3.06 1.68 1.63 8.18 7.98 8 3.61 3.29 1.68 1.63 9.86 9.61 period (0 to 2 or 3 weeks of age). In most instances, data on these nutrients are meager, and, with the exception of some research on dietary selenium and niacin requirements, only one report has appeared in the literature since 1980. Leclercq et al. (1990) reported that the calcium requirements of Muscovy ducks were 0.46 and 0.42 percent for age periods of 3 to 8 and 8 to 12 weeks, respectively. No information has been published recently on the calcium requirements for modern-day Pekin ducks. Body weight and feed consumption data for ducks from time of hatching to 8 weeks of age are given in Table 5-2.
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