PEARL MILLET PAPER: REVISED VERSION by Z39A3r

VIEWS: 21 PAGES: 12

									           Nutritional Evaluation of Pearl Millet (Pennisetum glaucum) for Pigs

                           O. Adeola, B.V. Lawrence, and J.C. Rogler
                                Department of Animal Sciences

        Pearl millet (Pennisetum glaucum) is a cereal grain with good drought tolerance and
hardiness commonly grown in the semiarid regions of Africa and Asia. Because of its drought
tolerance and relatively short growing period, pearl millet has the potential to be grown as a
double-crop and also may provide an alternative grain crop during years when inclement
weather patterns have delayed planting of corn such that yields would be adversely affected by
late summer drought or a short growing season. Pearl millet is likely to gain acceptance in
regions where it can be used as a double crop after wheat has been harvested. Thus, pearl
millet has the potential for providing an alternative grain source for grain and swine producers.
However, little information comparing the digestibility and utilization of corn and pearl millet in
the diets of swine is currently available. The higher protein, essential amino acid, oil (1 to 3
percentage points), and gross energy contents of pearl millet compared with other grains
suggest that pearl millet may be a valuable grain for use in the diets of the young pig. In order
to provide information on the dietary utilization of pearl millet grown under local conditions, four
experiments were conducted to evaluate the nutritional value of pearl millet grain compared with
corn. Pearl millet grown in two locations were used in the experiments.

                                  Experimental Procedures

        Four experiments were conducted to compare the nutritive value of pearl millet with that
of corn. In Experiment 1, nitrogen and energy digestibility of pearl millet, grown at the University
of Nebraska (PMA), or grown on non irrigated land near Purdue University in Indiana (PMA)
was compared with that of corn. Amino acid and mineral digestibility in PMA and PMB were
compared with that of corn in Experiment 2. Subsequent 28-d growth studies were conducted
with 10-kg (Experiment 3) and 24-kg (Experiment 4) pigs to examine the equal-weight
replacement value of pearl millet for corn. Before mixing the diets, pearl millet grain was
thoroughly cleaned, and all grains were hammer-milled with a 4-mm screen. Some small whole
pearl millet seeds were observed in all diets after milling.

Nutrient Digestibility
        Experiments 1 & 2. In each of Experiments 1 and 2, twenty-four crossbred barrows,
average initial weight of 20.7 kg, were used in a randomized complete block design with pigs
being blocked by weight and assigned to diet. Diets were formulated such that the test grain
was the only source of protein and energy in the diet. Both the corn and pearl millet samples
were hammer-milled and incorporated in diets (Table 1). Vitamins and minerals were supplied
in the diet to meet or exceed current requirements for the 20-kg pig (NRC, 1988). Pigs were
housed individually in stainless steel metabolism cages in an environmentally-controlled room
and allowed access to water ad libitum through a nipple waterer. Pigs were fed twice daily
and allowed 5 d to adjust to diets and metabolism crates. The adjustment period was followed
by 5 d of fecal and urine collection. Feces were collected twice daily, and weighed. Urine was
collected over the 5-d collection period. Urine volume was measured and recorded daily and
an aliquot taken.

Growth Performance
       Experiment 3. Sixty crossbred pigs, (30 barrows and 30 gilts) with an averaging 10 kg
in weight, were used in a 2 X 5 factorial arrangement (two sexes and five dietary treatments) in
a randomized complete block design. Pigs were blocked and assigned to treatment on the
basis of sex and initial weight. Pigs were individually housed in .86-m X .38-m pens on
elevated plastic coated wire floors and were allowed ad libitum access to feed and water. The
basal diet for the first 14-d was a typical corn-soybean meal diet with added dried whey and
contained 22% crude protein (Table 1). Remaining diets were formulated by replacing 25, 50,
75, or 100 % of the corn with PMA on an equal-weight basis; resulting in diets containing 1.29
to 1.35 % lysine. From d 14 to 28, pigs received a 20% crude protein diet (Table 1), in which
the same proportion of corn was replaced by PMA as in the first 14 d of the experiment,
resulting in lysine levels of 1.06 to 1.14%. Diets were formulated to meet or exceed current
NRC (1988) nutrient recommendations for the 10-kg pig. All pig weights and feed intakes were
recorded weekly.

        Experiment 4. Fifty crossbred pigs (25 barrows and 25 gilts), with an average initial
weight of 24.3 kg, were used in a 2 X 5 factorial arrangement (two sexes and five dietary
treatments) in a randomized complete block design (5 pigs per treatment combination; 10 pigs
per diet). Pigs were blocked and assigned to dietary treatment on the basis of sex and initial
weight. Dietary treatments consisted of a basal diet formulated to contain 16% crude protein
(Table 1), and the basal diet in which 25, 50, 75, or 100% of the corn was replaced with PMA,
weight:weight basis, resulting in lysine contents from .79 to .89 %. Diets (Table 1) were
formulated to meet or exceed current NRC (1988) recommendations for all nutrients for the 20-
kg pig. Pigs were individually housed in 1.73-m X .83-m pens with slatted concrete floors, and
allowed ad libitum access to feed and water. All pig weights and feed intakes were recorded
weekly.

Grains, diets and chemical analysis
        Samples of PMA, PMB, and corn were ground to pass through a 1-mm screen and
analyzed for dry matter (DM) crude protein (CP, N x 6.25), ether extract (diethyl ether) and acid
detergent fiber according to AOAC procedures. Energy values were determined using an
adiabatic bomb calorimeter. Grains, diets, feces and urine were analyzed for minerals by
Inductively-Coupled Plasma-Atomic Emission Spectroscopy using a Perkin Elmer Plasma 400
ICP-AES instrument. Samples of the grains equivalent to 100 mg of protein were hydrolyzed in
30 mL of 6 M HCl at 110o C for 24 h. Phenyl thiocarbamyl derivatives of the amino acids in the
6 M HCl hydrolyzates were separated by reverse-phased high-performance liquid
chromatography (Millipore, Bedford, MA, USA).

Statistical Analysis
         In Experiment 1, data were analyzed by the GLM procedures of SAS (1990) with three
diets and eight blocks in a randomized complete block design. For nitrogen, ether extract, and
energy digestibility data, nitrogen, ether extract, and gross energy intakes, respectively, were
included as covariates. Data from Experiment 2 were analyzed by the GLM procedures of SAS
(1990) with three diets and eight blocks in a randomized complete block design. Least
significant difference procedure was used for mean separation. The model used to analyze
data from Experiments 3 and 4 included sex, diet, and block in a randomized complete block
design. Orthogonal contrasts were used to determine linear and quadratic responses to
increasing pearl millet inclusion in Experiments 3 and 4. Individual pig served as the
experimental unit in each experiment.

                                   Results and Discussion

        Chemical Composition. Results for chemical composition analyses of corn, pearl millet
A and pearl millet B are presented in Table 2. Pearl millet was higher than corn in crude
protein, gross energy, ether extract, and acid detergent fiber content.    Nutrient profiles
indicate that pearl millet contains 27 to 32% more crude protein than corn, higher
concentrations of essential amino acids, two times as much ether extract, 2.25 and 1.2
percentage units more fiber, and a higher gross energy than corn. Pearl millet was higher in all

                                                2
essential amino acids including lysine than corn. The lysine concentrations in pearl millet
samples observed in the present study are similar to values reported by Burton et al. (1972). In
addition to lysine, methionine, threonine and tryptophan are commonly the most limiting amino
acids in grain-based diets used in animal nutrition. Methionine and threonine in pearl millet
were higher than in corn (Table 2). These data are in agreement with those of other authors
who have also reported pearl millet to have a higher crude protein content and higher essential
amino acid compared with corn (Ejeta et al., 1987; Smith et. al, 1989; Adeola et al., 1994)
sorghum, wheat, and triticale (Ejeta et al., 1987; Smith et al., 1989; Haydon and Hobbs, 1991).

        The higher ether extract content of the pearl millet would account for the higher gross
energy value of pearl millet. Variations in the absolute nutrient profiles of pearl millet have been
reported across various studies (Ejeta et al., 1987; Smith et al., 1989; Haydon and Hobbs,
1991, Adeola et al., 1994) and may be partially attributable to differences in environments in
which the grains were grown, agronomic practices employed, and the varieties of pearl millet
used in each study (Burton et al., 1972). Factors such as soil moisture content, level of nitrogen
in the soil and the time of nitrogen fertilizer application also influence protein content of cereals
(Wood et al., 1965).

        Mineral content (Ca, P, Mg, Mn, Zn, Fe, Cu) was also found to be higher in pearl millet
than corn (Table 2). Mineral content, especially calcium and phosphorus in pearl millet has
been reported to be generally similar to other cereals. Phosphorus in the two pearl millet
samples was 40 to 49% higher than in corn. It is known that over 65% of the phosphorus in
corn is organically bound in phytic acid which reduces the utilization of phosphorus and other
nutrients. The proportion of phosphorus in pearl millet that is bound in phytic acid is not known
in the current study.

         Nutrient Digestibility.     The results of Experiment 1 (Table 3) indicate total nitrogen
intakes were different (P<.01) between grains and between sources of pearl millet (P<.05),
because of the higher protein content of millet compared with corn, and PMB having a higher
protein content than PMA. As a result of the differences in nitrogen intake across dietary
treatments, nitrogen intake was used as a covariate in the analysis of digestibility and retention
data (superscript c, Table 3). Nitrogen digestibility was similar between the corn and PMB but
the nitrogen digestibility of the PMA was lower (P<.05) than corn but similar to that of PMB.
Although differences in nitrogen digestibility were detected, nitrogen retention as a percentage
of intake was unaffected (P>.05) by grain type or source of pearl millet. Total DM digestibility
also was higher (P<.01) for corn compared with pearl millet, with the DM digestibility of PMA
being lower (P<.05) than the DM digestibilities of corn or PMB.        The higher total ether extract
content of millet resulted in higher (P<.01) ether extract intakes; pigs fed PMA had a higher
(P<.05) ether extract intake than pigs fed corn or PMB. Although ether extract intake was
higher for pigs fed pearl millet, using ether extract intake was as a covariate in the analysis of
digestibility data (superscript d, Table 5) showed that digestibility values in pearl millet and corn
were similar. Regardless of the use of energy intake as a covariate in the analysis of energy
utilization data, energy digestibility, and retention as a percentage of intake were lowest (P<.01)
for pearl millet; and in conjunction with a lower DM digestibility, resulted in lower (P<.01) DE
and ME values for pearl millet than for corn.

         Information directly comparing the digestibility of pearl millet with corn in vivo for the pig
is currently unavailable. However, several studies have examined the ileal digestibility of amino
acids from either wheat and pearl millet (Haydon and Hobbs 1991), or wheat and corn
(Taverner et al. 1981). Haydon and Hobbs (1991) reported that the ileal digestibility of some
amino acids from pearl millet was higher than from wheat or triticale, although wheat and
triticale had higher total tract nitrogen digestibility values than pearl millet. The results of
Taverner et al. (1981) indicate that the ileal digestibility of amino acids may be lower for wheat

                                                   3
than for corn, however, the ileal availability of most amino acids from corn seems to be similar
to the values obtained by Haydon and Hobbs (1991) for pearl millet, thus supporting the similar
nitrogen retention values for corn and pearl millet obtained in Experiment 1. The results of
Experiment 1 also are supported by the in vitro pepsin digestibility studies by Ejeta et al. (1987)
who indicated that the overall protein digestibility of pearl millet was similar to that of corn. The
results of these studies, along with the higher protein/amino acid content of pearl millet, would
indicate that equal-weight substitutions of pearl millet for corn would result in an increase in the
supply of total available amino acids for growth.

        The higher ether extract content of the pearl millet compared with the corn used in this
experiment is consistent with the report of Burton et al. (1972) that pearl millet contains more oil
than most cereal grains and this difference would account for the higher GE value. The lower
energy digestibility, and the resulting lower DE and ME values of pearl millet, compared with
those of corn, are in agreement with the vast majority of the literature that is currently available.
Haydon and Hobbs (1991) reported that the energy value of pearl millet was lower than that of
soft red wheat, while Lin et al., (1987) reported that the energy digestibility of hard red wheat
was lower than corn, suggesting, that when fed to pigs, corn has the highest DE and ME value,
with wheat having a lower value than corn, but a higher value than pearl millet. These data are
in agreement with current NRC (1988) DE and ME values for the three cereal grains. Thus,
with increasing pearl millet inclusion, the GE value of the diet would increase while the supply of
DE and ME would decline.

         The higher fiber content of pearl millet compared with corn, or the presence of whole
pearl millet seeds in the diet, may be possible contributors to the lower DE and ME value of
pearl millet although the fat content is higher than that of corn. Singh et al. (1987) reported that
pearl millet may have a higher hemicellulose content than other grains, which may account for
the lower DM and energy digestibility, and thus the lower DE and ME values. The lower DE and
ME values of pearl millet compared with corn reported in this study are in disagreement with
recent results reported by Adeola et al. (1994) in which the DE and ME values of pearl millet for
ducks was higher than that for corn. As the diets in this study and the study of Adeola et al.
(1994) were prepared in a similar manner, the ducks may have been able to utilize the whole
grain present in the diets, which would have accounted for reduced available energy to the pigs
in this study.

Dry Matter and Amino Acid Digestibility. Results for fecal digestibility of dry matter and amino
acid in corn and pearl millet are presented in Table 4. Dry matter intake was similar for corn
and pearl millet. However, dry matter output was higher (P < .05) for pearl millet than corn
resulting in lower dry matter digestibility values for pearl millet (Table 4). Presumably, the
higher fecal dry matter output with pearl millet diets was due to the higher fiber content (Table
2). The lower digestibility values observed for dry matter and energy in pearl millet might be due
to higher crude fiber level in the pearl millet (corn, 2.81%; PMA, 3.84%; PMB, 3.62%). Higher
insoluble dietary fiber (cellulose, pectin, xylan) and the relationship between fiber components
and enzyme inhibition (for example, inhibition of trypsin activity by pectin and xylan) have been
associated with low dry matter and energy digestibility in pearl millet when compared with other
cereals (Haydon and Hobbs, 1991).

        Among the essential amino acids, arginine, threonine, valine, isoleucine, and lysine had
higher (P < .05) digestibility values for pearl millet than corn (Table 4). These results support
the report of Haydon and Hobbs (1991) that pearl millet exhibits higher apparent small intestine
digestibility of essential amino acids than other grains. The higher digestibility values for amino
acids in pearl millet in the current study might be due to higher oil content in the pearl millet.
Increased dietary fat has been shown to influence amino acid digestibility Imbeah and Sauer
(1991). In a recent study, Li and Sauer (1994) showed that increasing the level of canola oil in

                                                  4
the diet of young pigs from 3.2 to 12.2% resulted in a linear increase in ileal digestibility of
arginine, threonine, valine, isoleucine and lysine. The results of the current study demonstrate
that the inclusion of pearl millet in the diet of growing pigs will likely increase its caloric value,
with the possibility to reduce the amount of added fat as well as enhance the digestibility of
essential amino acids. Increased dietary fat is known to delay gastric emptying rate thereby
increasing retention time of feed in the gastrointestinal tract. The increased retention time of
feed in the gastrointestinal tract might provide dietary protein more time for digestion, hence
the increased digestibility. Digestibility of histidine, methionine, leucine and phenylalanine was
the same for corn and pearl millet. Digestibility of nonessential amino acids in corn and pearl
millet was similar, except for aspartic acid which was observed to be more digestible in pearl
millet (Table 4).

Mineral Balance.       Results for mineral balance for corn and pearl millet are shown in Table 5.
The values for calcium intake, absorption and retention were not significantly different for corn
as compared with pearl millet. Phosphorus intake, fecal and urinary outputs were higher for
pearl millet than corn. However, the percentage of phosphorus absorbed was higher for corn
than pearl millet. Pearl millet is usually higher in ash, but has been observed to be similar to
other cereals in calcium and phosphorus content and metabolism (Burton et al., 1972).
Magnesium and manganese intake were higher for pearl millet than corn; however, absorption
and retention of the two minerals were similar for corn and pearl millet. The same trend was
observed for zinc and copper where intake and fecal output were higher for pearl millet, but
absorption and retention were similar for corn and pearl millet.

Growth performance. Daily gain (Table 6) during the first 14 d in Experiment 3, and over the
entire 28-d period was unaffected (P>.05) by dietary treatment with all pigs weighing an
average of 16.3 kg at d 14, and 25.0 kg at d 28. From d 14 to 28, however, rate of BW gain
and feed intake responded quadratically (P<.05) to increases in substitution of pearl millet for
corn with the maximum rate of weight gain achieved when 25% of the corn was replaced with
pearl millet. The higher rate of gain and feed intake was also associated with a numerical
improvement (P=.19) in the gain:feed ratio at the 25% replacement level. The substitution of
pearl millet for corn (weight basis) in Experiment 4 resulted in non-significant (P>.05), numerical
increases in the rate of BW gain and feed intake (Table 7). Gain:feed ratio was also unaffected
(P>.05) by substitution of pearl millet for corn. Body weights were similar across dietary
treatments at the end of the 28-d experiment.

        The ability of pearl millet to support growth in pigs has received very little attention
(Haydon and Hobbs, 1991). Pearl millet has, however, been successfully used in the diets of
ducks (Adeola et al., 1994) and broilers (Sharma et al., 1979; Smith et al., 1989 and Sullivan et
al., 1991) as a replacement for corn. Adeola et al. (1994) reported that the growth rate of ducks
fed diets in which corn had been replaced with pearl millet on a weight basis were comparable
with the growth rates of ducks fed-corn based diets. Furthermore, Sharma et al. (1979)
reported that at low rates of inclusion of millet, wheat, and sorghum, to corn-based diets for
broilers, diets containing millet supported greater weight gains than those containing wheat or
sorghum, and corn diets supplemented with millet resulted in greater weight gains than diets
containing corn as the major energy source. Similarly, Smith et al. (1989) reported that weight
gains for chicks fed diets containing pearl millet or sorghum were comparable to weight gains of
broilers fed corn-based diets.

                                           Application
       This study has provided detailed data for chemical composition, digestibility of amino
acids with nitrogen and mineral balance in pearl millet compared with corn. Pearl millet was
found to be higher than corn in crude protein, gross energy, oil, fiber, amino acid and mineral
content. Based on the apparent nutrient and amino acid digestibilities reported in this study,

                                                   5
pearl millet has high nutritive value and can be used as an alternative grain in swine. Although
higher in gross energy, pearl millet has lower digestible and metabolizable energy values than
corn when fed to pigs. The nitrogen digestibility of pearl millet was comparable with that of
corn, indicating that the protein in pearl millet is well utilized in pig diets. Replacement of corn
with pearl millet on an equal-weight basis in the diets of young pigs did not affect growth
performance, other than slight increases in gain and feed intake.

                                        Literature Cited

Adeola, O., J. C. Rogler, and T. W. Sullivan. 1994. Pearl millet in diets of White Pekin ducks.
        Poult. Sci. 73:425.
AOAC. 1980. Official Methods of Analysis (13 th Ed.). Association of Official Analytical
        Chemists, Washington, DC.
Burton , G. W., A. T. Wallace, and K. O. Rachie. 1972. Chemical composition and nutritive
        value of pearl millet (Pennisetum typhoide (Burm.) Staph and E. C. Hubbard) grain.
        Crop Sci. 12:187.
Ejeta, G., M. M. Hassen, and E. T. Mertz. 1987. In vitro digestibility and amino acid composition
        of pearl millet (Pennisetum typhoides) and other cereals. Proc. Natl. Acad. Sci. 84:6016.
Haydon, K. D., and S. E. Hobbs. 1991. Nutrient digestibilities of soft winter wheat, improved
        triticale cultivars, and pearl millet for finishing pigs. J. Anim. Sci. 69:719.
Imbeah, M., and W.C. Sauer. 1991. The effect of level of dietary fat on amino acid
        digestibilities in soybean meal and canola meal and on the rate of passage in growing
        pigs. Livest. Prod. Sci. 29: 227.
Li, S. and W.C. Sauer. 1994. The effect of fat content on amino acid digestibility in young pigs.
        J. Anim. Sci. 72:1737.
Lin, F. D., D. A. Knabe, and T. D. Tanksley, Jr. 1987. Apparent digestibility of amino acids,
        gross energy and starch in corn, sorghum, wheat, barley, oat groats and wheat
        middlings for growing pigs. J. Anim. Sci. 64:1655.
NRC. 1988. Nutrient Requirements of Swine (9th Ed.). National Academy Press, Washington,
        DC.
SAS. 1990. SAS User's Guide: Version 6 (4th Ed.). SAS Inst., Inc. Cary, NC.
Sauer, W. C., S. C. Stothers, and G. D. Phillips. 1977. Apparent availabilities of amino acids
                 in corn, wheat, and barley for growing pigs. Can. J. Anim. Sci. 57:585.
Sharma, B. D., V. R. Sadagopan, and V. R. Reddy. 1979. Utilization of different cereals in
        broiler diets. Br. Poult. Sci. 20:371.
Singh. P., U Singh, B. O. Eggum, K. A. Kumar, and D. J. Andrews. 1987. Nutritional evaluation
        of high protein genotypes of pearl millet (Pennisetum americanum (L.) Leeke). J. Sci.
        Food Agric. 38:41.
Smith, R. L., L. S. Jensen, C. S. Hoveland, and W. W. Hanna. 1989. Use of pearl millet,
        sorghum, and triticale grain in broiler diets. J. Prod. Agric. 2:78.
Sullivan, T. W., J. H. Douglas, D. J. Andrews, P. L. Bowland, J. D. Hancock, P. J. Bramel-Cox,
        W. D. Stegmeier, and J. R. Brethour. 1990. Nutritional value of pearl millet for food and
        feed. Pages 83-94 in Proceedings of the International Conference on Sorghum
        Nutritional Quality. Purdue University, West Lafayette, IN.
Taverner, M. R., I. D. Hume, and D. J. Farrell. 1981. Availability to pigs of amino acids in cereal
        grains 2. Apparent and true ileal availability. Br. J. Nutr. 46:159.

                                    Acknowledgments
      This study was supported by Purdue University New Crops Center and Indiana Value
Added Grant Program, ISTA Center, Indianapolis IN 46204.




                                                  6
Table 1.    Composition (%) of corn and pearl millet diets.
                         Experiments 1&2       Experiment 3                Experiment 4

Ingredient                                    1 to 14 d       14 to 28 d
Grain                 95.97                   50.95           66.75        76.98
Soybean meal (48% CP) --                      34.75           29.15        19.69
Whey                   --                     10.00           --           --
Lard                   --                     1.00            1.00         --
Dicalcium Phosphate    2.40                   1.70            1.70         1.80
Limestone              0.50                   0.75            0.75         0.70
Salt                   0.25                   0.25            0.25         0.25
Vitamin Premix         0.50                   0.25            0.25         0.20
Trace Mineral Premix   0.10                   0.10            0.10         0.10
Selenium Premix        0.15                   0.15            0.15         0.15
Tylan                  0.13                   0.10            0.10         0.13
Total                100.00                   100.00          100.00       100.00




                                          7
Table 2.      Chemical composition of corn and pearl millet used in the Experiments.
                             Cereal Grain

Nutrient                      Corn               Pearl Millet A         Pearl Millet B
Dry matter, %               88.41                89.08                  90.12
Crude Protein, %             7.54                10.03                  11.06
Gross energy, kcal/kg     3788                   4132                   4307
Ether extract, %             1.51                5.06                   6.39
Acid detergent fiber, %      2.81                3.84                   3.62
Minerals, mg/kg
Zinc                        16                   35                     43
Phosphorus                2242                   3148                   3343
Manganese                    5                   11                     12
Iron                        19                   40                     51
Magnesium                  938                   1239                   1351
Calcium                     48                   153                    208
Copper                       2                   5                      6

Indispensable amino acids, %
Arginine                       0.38              0.56                   0.63
Histidine                      0.21              0.27                   0.29
Isoleucine                     0.40              0.59                   0.68
Leucine                        0.95              1.03                   1.16
Lysine                         0.23              0.35                   0.36
Methionine                     0.17              0.23                   0.23
Phenylalanine                  0.41              0.54                   0.59
Threonine                      0.27              0.42                   0.44
Valine                         0.40              0.58                   0.65
Dispensable amino acids, %
Alanine                        0.58              0.79                   0.91
Aspartic acid                  0.52              0.83                   0.91
Glutamic acid                  1.41              1.90                   2.16
Glycine                        0.29              0.38                   0.39
Proline                        0.66              0.65                   0.74
Serine                         0.38              0.49                   0.55
Tyrosine                       0.31              0.38                   0.41




                                             8
Table 3. Nutrient digestibility of corn and pearl millet in Experiment 1a

Item                              Corn         Pearl Millet A      Pearl Millet B      SE

DM digestibility, %                 87.2h          75.5f              78.7g         0.81
Nitrogen
    Intake, g/db                    11.8f          15.9g              17.6h         0.45
    Absorption, g/db                 8.6f          10.7g              12.4h         0.36
    Digestibility, %b               72.8g          67.2f              70.5g         1.01
    Retention, g/db                  6.4f           8.4g              10.2h          .24
    Retention, % of intakeb         54.3           52.8               57.6          1.66
    Absorption, g/dc                11.0g          10.1f              10.6g          .16
    Digestibility, %c               73.2g          67.1f              70.1fg        1.05
    Retention, g/dc                  8.74           7.87               8.41          .24
    Retention, % of intakec         57.2           52.2               55.3          1.66
Ether extract
    Intake, g/db                    26.9f          60.5h              55.7g         1.53
    Absorption, g/db                 7.6f          25.3h              22.6g         1.57
    Digestibility, %b               28.3f          41.9g              40.3g         3.15
    Absorption, g/dd                19.5           17.9               18.0          1.33
    Digestibility, %d               34.8           37.9               37.7          3.19
Energy
    GE intake, Mcal/db               3.76           3.97               3.89         0.07
    Absorption, Mcal/db              3.23g          2.91f              2.96f        0.04
    Digestibility, % of intakeb     85.8g          73.4f              76.0f         0.89
    Retention, Mcal/db               3.16g          2.85f              2.90f        0.04
    Retention, % of intakeb         83.9h          71.8f              74.4g         0.89
    DE value, Mcal/kgb               3.17g          2.90f              2.94f        0.03
    ME value, Mcal/kgb               3.08g          2.83f              2.88f        0.03
    Absorption, Mcal/de              3.31g          2.84f              2.95f        0.04
    Digestibility, % of intakee     85.6g          73.5f              76.0f         0.90
    Retention, Mcal/de               3.24g          2.78f              2.89f        0.04
    Retention, % of intakee         83.9g          71.8f              74.4f         0.89

aData are means of eight 20-kg barrows per treatment.
bData are means from analysis of variance.
cData are least squares means from analysis of covariance using nitrogen intake as a
covariate.
dData are least squares means from analysis of covariance using ether extract intake as a
covariate.
eData are least squares means from analysis of covariance using gross energy intake as a
covariate.
fghDifferent superscripts within the same row are different at P<.05.
Table 4.      Apparent digestibility of dry matter and amino acid in corn and pearl
              millet in Experiment 2.

Nutrient                          Corn            Pearl Millet A   Pearl Millet B        SE

Dry matter
Dry matter intake, g/d       866.27               874.53           891.84                13.04
Fecal dry matter output, g/d 114.20b              169.47a          160.54a               6.07
Dry matter digestibility, %   86.83a              80.85b           82.03b                0.60
Indispensable amino acid digestibility, %
Arginine                     81.27b           84.70a               85.71a
0.89
Histidine                     79.08           79.56                79.88
1.03
Isoleucine                   70.50c           75.67b               77.26a
1.43
Leucine                       83.53           81.53                82.92
0.94
Lysine                       65.50b           77.23a               72.18a
1.96
Phenylalanine                 77.70           79.01                80.32
1.06
Methionine                    77.05           79.50                77.53
1.46
Threonine                    62.92b           71.85a               70.99a
1.66
Valine                       73.71b           77.50a               78.55a
1.24
Dispensable amino acid digestibility, %
Alanine                       76.00           77.61                78.42
1.26
Aspartic acid                71.95b           76.09a               77.65a
1.58
Glutamic acid                 82.38           82.45                83.99
0.96
Glycine                       66.47           68.05                65.80
1.66
Proline                      85.87a           82.79b               84.12a,b
0.72
Serine                        73.85           76.03                77.38
1.30
Tyrosine                      73.36           73.34                74.03
1.23


a,b,cMeans without a common superscript along rows are different (P < .05). Each value
      represents mean from eight pigs.




                                             10
Table 5. Calcium, phosphorus, magnesium, manganese, zinc, and copper balance for corn
             and pearl millet in Experiment 2.

Mineral                      Corn           Pearl Millet A    Pearl Millet B     SE

Calcium, mg/d
Intake                6760                  6833              6912               135
Absorbed              2985                  2596              2542               259.52
Retained              2896                  2487              2438               259.71
Phosphorus, mg/d
Intake                6477b                 7285a             7528a              105
Absorbed              3445                  3579              3664               160
Retained              2895                  2757              2842               161.79
Magnesium, mg/d
Intake                 884.25c              1160.76b          1269.43a           16.30
Absorbed               221.02               265.94            255.41             25.62
Retained               157.86               174.36            181.76             27.11
Manganese, mg/d
Intake                  58.95b              64.43a            65.58a             0.93
Absorbed                12.76               6.02              10.09              3.11
Retained                                    12.49             5.83               9.86     3.11
Zinc, mg/d
Intake                 211.24b              228.44a           235.88a            3.33
Absorbed               106.07a              85.47b            97.85a             4.35
Retained               104.65a              83.87b            96.17a             4.30
Copper, mg/d
Intake                  18.67c              20.51b            21.53a             0.30
Absorbed                 5.09               3.81              4.04               0.59
Retained                 5.02               3.74              3.96               0.59

a,b,cMeans without a common superscript along rows are different (P < .05). Each value
represents mean from eight pigs.




                                            11
Table 6. Growth performance in response to increasing the weight:weight substitution of pearl
millet (PM) for corn in diets fed to 10-kg pigs in Experiment 3a

Item                   Control     25% PM         50% PM         75% PM 100% PM                       SE         P<b
Gain, g/d
   Day 0 to 14         466         463            409            478             436                 42.1        NS
   Day 14 to 28        570         698            652            602             556                 37.2        *
   Day 0 to 28         518         581            531            543             508                 27.7        NS
Intake, g/d
   Day 0 to 14         835          893            853            887             806                47.3        NS
   Day 14 to 28      1,187        1,322          1,270          1,170           1,176                43.0        *
   Day 0 to 28       1,011        1,107          1,061          1,037             995                38.4        NS
Gain:feed, g:g
   Day 0 to 14           0.54           0.52           0.47            0.53           0.54           0.04        NS
   Day 14 to 28          0.48           0.53           0.52            0.51           0.47           0.03        NS
   Day 0 to 28           0.50           0.52           0.50            0.52           0.51           0.02        NS

aData are means of six barrows and six gilts per treatment.

bProbability of quadratic response to increasing pearl millet substitution; NS = not significant, *
= P<.05.




Table 7. Growth performance in response to increasing the weight:weight substitution of pearl
millet (PM) for corn in diets fed to 20-kg pigsa

Item                         Control      25% PM            50% PM       75% PM         100% PM             SE   P<b

Initial weight, kg              24.0           24.3           24.2            24.2           24.7       0.65     NS
Final weight, kg                45.5           46.3           46.2            46.6           48.2       1.02     NS
Intake, kg/d                     1.93           1.99           2.135           2.02           2.15      0.11     NS
Gain, kg/d                       0.77           0.79           0.78            0.80           0.84      0.04     NS
Gain:feed, kg:kg                 0.39           0.39           0.37            0.39           0.39      0.01     NS

aData are means of five barrows and five gilts per treatment.

bProbability of response to increasing pearl millet substitution; NS = not significant.




                                                       12

								
To top