Gene

A. Spiller,

Sidney

Saperstein,

Myron

A. Beigler

and Ronald

J. Amen

ABSTRACF Fiber-free liquid diets containing isonitrogenous amounts of various dietary nitrogen sources were fed to five adult male pig-tailed monkeys (Macace nemestrina) with a mean weight of approximately 10 kg. All liquid diets supplied 3.0 g N/day per monkey and maintained the animals in a positive nitrogen balance. Initial baseline fecal output data were obtained by feeding the animals a commercial solid monkey chow. The dietary nitrogen sources fed were a) egg white protein, b) an enzymatic hydrolysate of fish protein supplemented with L-amino acids to simulate the egg albumin pattern, c) a mixture of pure L-amino acids simulating the egg pattern, d) a casein hydrolysate supplemented with amino acids, and e) an amino acid mixture with Rose’s pattern. Total fecal matter, dry fecal matter, percent of moisture, fecal nitrogen, lipids and ash were determined for a 1 0-day period for each experimental diet. A very significant difference (P < 0.001) was noted between each liquid diet and the solid chow, but no significant differences were found between the various fiber-free liquid diets, pointing to the effect of fiber as a major factor affecting fecal output. Monkeys fed liquid diets excreted fecal matter with a mean of 12.9 g/day, of which 4.7 g/day was dry feces (fecal dry matter 28.5%). Fecal nitrogen was found to be 0.25 g, fecal lipids were 0.19 g, and fecal ash was 0.59 g/day per monkey, respectively. Am. J. Clin.Nutr. 28: 502-506, 1975.

The amount of fecal output is of interest in pre- and postsurgical nutrition and in other clinical situations where the intestine should contain little or no food residue and as little as possible endogenous output (1, 2). In recent years there has been increasing interest in the use of well-defined soluble diets for this purpose (3-6), often called “elemental” or “chemically defined” diets. These diets have often been used to replace the regimen of low-residue foods (7-11). Macronutrients, as well as fiber, change fecal output and composition either because some undigested nutrients reach the colon, or, because of their effect on various gastrointestinal endogenous secretions, cell loss or bacterial growth. This study was designed to examine the effect on fecal output in nonhuman primates of an intact protein, an enzymatic protein hydrolysate, an L-amino acid mixture with a similar essential amino acid pattern, and two commercially available low-residue diets. Pigtailed monkeys (Macaca nemestrina) were used as models. The gastrointestinal tract of this 502

TheAmerican

Journal

of Clinical

animal is extremely similar is free from the large cecum

Materials Animals

to that present

of man in rats.

and

and Methods and housing

Male, adult pig-tailed

monkeys (Macace nemestrina) weighing 8 to 15 kg were quarantined according to standard procedures. After termination of quarantine, they were preconditioned by placing them on a regimen of liquid diets for 30 days prior to the start of the experiment. The animals were housed individually in metabolic cages that had been designed so that the lower half was covered with a solid vertical sheet of metal to prevent loss of feces or urine to the outside of the cage. There were two internally stacked floors which were removable and allowed for complete collection of feces. Water was supplied ad libitum and the diet ‘From the Institute of Agriscience and Nutrition, Syntex Research, 3401 Hillview Ave., Palo Alto, California 94304. ‘ data presented at the 58th Annual Meeting of the Federation of American Societies for Experimental Biology, April 10, 1974. Atlantic City, New Jersey.

Nutrition

28: MAY

1975,

pp 502-506.

Printed

in U.S.A.

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Effect on fecal output of various dietary nitrogen sources in pig-tailed monkeys (Macaca nemes trina) fed fiber-free, semisynthetic diets1’ 2

DIETARY TABLE

Protein, pig-tailed

1 fat and carbohydrate monkeys (Mactwa

composition of fiber-free nemestrina), g/100 ml diet Hydrol

Diets

AND

FECAL

liquid

1

diets

Serine Glutamic Glutamine

acid

Proline

Cystine Alanine Valine Methionine Isoleucine Leucine Tyrosine Phenyalanine Tryptophan Fat Corn oil Safflower oil Soy oil and medium triglycerides Carbohydrate Corn syrup

2

A.A.

220b

1

A.A.

2

2.so

2.04”

0.262 0.075 0.159 0.267 0.124 0.107 0.394

0.262 0.075 0.159 0.267 0.124 0.107 0.394

0.10 0.04 0.17 0.20

0.093 0.013 0.116 0.162 0.124 0.163 0.214 0.068 0.144 0.026

0.093 0.013 0.116 0.162 0.124 0.163 0.214 0.068 0.144 0.026

2.6

2.6

Egg white 250d

0.09 0.06 0.33 0.13 0.10 0.10 0.09 0.09 0.14 0.11 0.10 0.03

2.6 0.13

3.4

chain

17.0

solids

and glucose

fed to

Hydrol

2.50#{176}

Amino acid pattern of the protein Lysine Histidine Arginine Aspartic acid Threonine

503

OUTPUT

15.4

17.0

17.0 22.6

oligo-

saccharides a

Enzymatic

hydrolysate

of fish

protein

supplemented

supplemented with L-methionine, L-tryptophan manufacturer. C Made up entirely of pure L-amino acids. casein,

was fed by means of a watering bottle fitted with a ball point feeding tube to prevent dripping. The feces and urine were collected once a day between 8:00 and 9:00 AM, before the morning feeding. After weight or volume was determined, the specimens were immediately frozen for future analyses. Diets

A commercial monkey chow (Purina Monkey Chow),3 supplemented with vitamin C, was used for comparison with the fecal output on the other diets. All determinations on the solid chow were performed first. The monkeys were then adapted to a liquid diet regimen by feeding an egg white diet (Table 1) plus 10% apple juice and 2% cellulose4 for 1 week. This was followed by 3 weeks on a liquid egg white diet in which the fiber and apple juice had been omitted. No physiological measurements were performed during this period. After adaptation, each experimental liquid diet was

with

L-amino

acids.

b Enzymatic

and

L-tyrosine; amino acid d Intact egg white protein.

fed twice daily morning after afternoon.

pattern

hydrolysate not

given

of by

for a period of 2 weeks; once in the fecal collection and once in the

The diet composition is presented in Tables 1 and 2. All diets were mixed to supply a caloric density of 1 kcal/ml and a total of 3.0 g of nitrogen/day per monkey. These values had been previously established as the amount necessary to maintain adult male pig-tailed monkeys weighing approximately 1 0 kg in a positive nitrogen balance. Hydrol 1 contained a fish protein hydrolysate suppleffiented with L-amino acids to yield the pattern given in Table I , column 1 : A.A.1 contained a mixture of L-amino acids with the same pattern as Hydrol 1 . The latter two diets simulated the pattern of the egg white diets. All other ingredients 3 Approximate analysis per 100 g: protein 15.0%, fat 5.0%, carbohydrate (by difference) 65.0%, crude fiber 3.0%, ash 5.0%, moisture 7.0%. Fed ad libitum. 4

Solka

Hampshire.

Floc, 90% cellulose,

Brown

Co., Berlin,

New

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Protein

Glucose

NITROGEN

SPILLER

504 TABLE

2

Vitamin

and mineral

pig-tailed

monkeys

Hydrol

ml

Riboflavin,mg/lOOml

Pyridoxine,mg/lOOml Biotin, g/100 ml Folic acid, mg/100 ml VitaminB,2 ig/100ml

Choline,mg/lOOml VitaminA,IU/lOOml VitaminD3,IU/lOOml Vitamin E, IU/100

ml

Minerals Potassium,mg/looml Sodium, mg/l00 ml Calcium, mg/100 ml Magnesium, mg/100 ml Phosphate(P04),mg/lOOml Chloride, mg/100 ml Iron, mg/100 ml Zinc, mg/100 ml Manganese, mg/100 ml Copper,mg/lOOml Iodine, ig/l00 ml

1

Hydrol

pasteurized

after

each

experimental

at

71

rapidly

cooled

did not

begin

diet

was

C

for

was

determined

by

drying

the

Egg white

14.30 0.14 14.30 0.71 0.14 0.14 2.86 0.06 0.71 14.30 286 57 1.5

90.1 39.8 78.8 1 8.9 99.3 121.5 0.9 0.3 0.1 0.02 7.5

152.0 36.0 52.0 1 7.5 120.4 120.0 0.5 0.5 0.2 0.1 7.0

90.1 39.8 78.8 1 8.9 99.3 121.5 0.9 0.3 0.1 0.02 7.5

116.8 85.9 44.4 19.4 121.0 180.1 0.5 0.7 0.2 0.1 7.9

90.1 39.8 78.8 18.9 99.3 121.5 0.9 0.3 0.1 0.02 7.5

and

at 5 C

insured

day that

the previous diet had cleared the intestinal tract. All values reported are daily means for a 10-day period. Five-day fecal composites for each monkey were acidified with acetic acid, defoamed with octanol and homogenized in a Waring Blendor. Aliquots of the homogenate were used for subsequent analyses. Dry matter

2

3.80 0.07 0.73 0.55 0.07 0.11 1 .10 0.006 0.27 8.47 275 3 0.08

the fourth

This

A.A.

14.30 0.14 14.30 0.71 0.14 0.14 2.86 0.06 0.71 14.30 286 57 1.5

stored

until fed.

1

5.00 0.07 0.90 0.50 0.08 0.10 7.52 5.00 0.25 5.00 250 20 1.5

1 5 min

and

A.A.

14.30 0.14 14.30 0.71 0.14 0.14 2.86 0.06 0.71 14.30 286 57 1.5

were similar in these three diets. Hydrol 2 was a commercial low-residue diet made from casein hydrolysate and supplemented with amino acids Lmethionine, L-tyrosine and L-tryptophan. A.A.2 was also a commercial low-residue diet containing L-amino acids with the pattern recommended by Rose (12) for man, shown in Table 1 , column 4. A total of 800 ml of Hydrol 2 and 850 ml of A.A.2 were fed daily to supply isonitrogenous levels per day in all diets. The caloric density of 1 kcal/ml was maintained. All ingredients were dispersed in water. The was

2

homogenate

to

constant weight in a vacuum oven at 70 C. The dried feces were then ashed in a muffle furnace at 600 C. Nitrogen content was determined by the A.O.A.C. macro-Kjeldahl method (1 3). Lipid content was determined by the method of Van de Kamer et al. (14).

Monkey body weights were after the liquid diet conditioning of the experiment.

Results

determined before and period and at the end

and discussion

The weights of dry and wet feces are presented in Table 3. The weights are calculated as the mean per day per monkey on each diet for the 10-day period. In addition, this table shows the percentage of dry matter in the feces as well as the wet and dry fecal induction ratios (FIR). The FIR are expressed as follows: Wet FIR

-

daily fecal output daily

food intake

(g) (kcal) x

D ry FIR

--

100 (g/100

kcal)

100 (g/100

kcal)

daily daily fecal food dry intakematter (kcal) (g) x

The possible effects of variation due to caloric intake on fecal output are taken into account by means of these calculations. Table 3 compares the values for wet and dry

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Vitamins Ascorbic acid, mg/100 ml Thiamin,mg/lOOml Niacinamide,mg/lOOml D-Pantothenic acid, mg/100

homogenized, then until feeding time. Fecal collections

AL.

composition of fiber-free liquid diets fed to (Macace nemestrina), analysis/100 ml diet

Diets

mixture

ET

DIETARY

NITROGEN

AND

FECAL

OUTPUT

Liquid containing as those

diet A.A.1 the same produced

However,

feces

liquid

diets

content

produced

showed

the

72.4%; physiological

1,

not

statistically

further interest

colonic

values

show

no

the

The

values

mean

and

based

for

mens.

animals are It appears

and

between

on

ash

any

of

hydroysates

(Table

or

4).

nitrogen

given

levels

in Table

found

pig-tailed

(0.22

processes.

lipid

difference

per

4 are

(unpublished

monkeys

g/day

In the absence of feces are primarily

the

73.8%;

content

disease

nitrogen,

mixtures

diets

2,

of the recently low fiber diets,

several

fecal

for

tein-free

Hydrol

moisture

endogenous

observations)

four

moisture

significant

diets acid

other

70.3%). Perhaps of this higher, but

significant

L-amino

76.1%;

study in view in high and

for

liquid

the

higher

egg white, significance

function,

The

the

and

by

a slightly

(Hydrol

A.A.2,

deserves renewed

(Table 3) produced feces amount of fecal moisture by solid chow (64.7%).

10-kg

fed

pro-

monkey).

fiber, this suggests that the of endogenous origin when

placed on these dietary regithat the egg white protein is

TABLE3

Daily fecal output on liquid fiber-free compared to output on solid monkey

diets for adult, chow#{176}

male

pig-tailed

monkeys

(Macaca

nemestrina)

Mean

Hydrol Number

of monkeys

Wetfecaloutput,g Dry fecal output, g WetFIR,g/lOOkcal Dry FIR, g/100 kcal Fecal dry matter,%

1

5 12.0±1.9 2.9 ± 0.3 1.9±0.4 0.4 ± 0.1 23.9 ± 3.5

Hydrol

2

5 11.2±1.6 ± 0.2 1.8±0.2

2.7 0.4

±

0.0

26.2

±

1.8

A.A.1

A.A.2

5 11.6±2.2 3.6 ± 0.8 1.7±0.4 0.5 ± 0.1 35.3 ± 7.0

Values are daily means ± standard error of the mean fecal output, dry fecal output, wet FIR and dry FIR

for

#{176}

wet

Egg

5 13.4±3.3 2.8 ± 0.3 1.9±0.4 0.4 ± 0.1 27.6 ± 4.0 a 10-day

are significantly

white

5 16.4±1.4 4.7 ± 0.3 2.4±0.2 0.7 ± 0.0 29.7 ± 1.3

period. b Solid different from

liquid

Solid

diets

12.9±0.9 3.3 ± 0.3 1.9±0.1 0.5 ± 0.1 28.5 ± 1.9

monkey

chowb 5 93.1±7.3 33.3 ± 3.4 31.8±2.9 11.1 ± 0.8 35.3 ± 1.2

monkey chow values for values for liquid diets (P



the

0.5).

liquid

the

liquid

diet

1 1 .8 ± 1 .8 kg,

diet

1 1 .4 ± period,

conditioning

Hemoglobin,

electrolytes, show

of

was

± 1.6 kg at the end of the experiment. the changes are statistically significant

of

(P

beginning

period

hematocrit,

albumin

any

and

significant

did

throughout

not

from

the

difference

between

drolysates

or

lating fecal

present

a low output.

the

L-amino lack

egg white

respect

to

slight

increase

in

of

there

8.

9.

hy-

diet,

digestibility

which

relative

to with

resulted

obtain

a low

time,

dietary

factor Further

affecting studies

fecal

fiber

output. appears

fecal output are in progress

At to

be

the the

10.

in a

is probably

of

little clinical significance. It appears that the choice of diet for clinical use should be based on the patient’s need and ability to handle intact protein and not entirely on the presentation of amino acid diets in order to

7.

in formu-

clinical

residue

5.

is no

protein

mixtures

of total

protein fecal

that

use

acid

residue The

study,

Bela Szakacs

various

macronutrients

on

El

composition.

thank

William

for their

1 . AHRENS, E. H. The metabolic studies: vances in Metabolic Levine and R. Luft. 2. BUNTE, H. Preparing cally defmed diet. on Balanced Nutrition Lang, W. FekI and 1971. 3. WINITZ, M., D. A. Studies in metabolic cally defined diets. human males. Am. 4. BEIGLER, M. A.

the

liquid diet conditioning or the experimental diet period; therefore, no values are reported. If the intestinal physiology of the Macaca nemestrina is similar to that of man, it would appear

authors

of

and

Benken,

technical

Robert

Marks

assistance.

References

6.

plasma

globulins

change

and

ratios

in Table

ash for animals higher (P < 0.001) than those fed liquid fiber-free diets. The loss of nitrogen, lipids and ash in the feces induced by the solid chow diets appears fed

nitrogen,

the

nitrogen

present major

and composition. to determine the

11. 12. 13.

14.

use of liquid formula diets in 15 years experience. In: AdDisorders, edited by R. New York: Academic, 1970. for surgery with a chemiIn: International Symposium and Therapy, edited by K. G. Berg. Stuttgart: Thieme,

SEEDMAN AND J. GRAFF. nutrition employing chemiI. Extended feeding of normal J. Clin. Nutr. 23: 525, 1970. The elemental diet: a new concept in nutritional support of the debilitated patient. Surg. Digest. 6: 18, 1971. GLOTZER, D. J., P. L. BOYLE AND W. SILEN. Preoperative preparation of the colon with an elemental diet. 74: 703, 1973. KARK, R. M. Liquid formula and chemically defined diet. J. Am. Dietet. Assoc. 64: 476, 1974. HOSOL, K., W. C. ALVAREZ AND F. C. MANN. Intestinal absorption: a search for a low residue diet. Arch. Intern. Med. 41: 112, 1928. WILLIAMS, R. D., AND W. H. OLMSTED. The manner in which food controls the bulk of the feces. Ann. Intern. Med. 10: 717, 1936. AMERICAN DIETETIC ASSOCIATION, AMERICAN MEDiCAL ASSOCIATION, JOINT COMMITTEE ON DIET. Diet as related to gastrointestinal function. J. Am. Dietet. Assoc. 38: 426, 1961. CALLOWAY, D. H. End products of human metabolism as affected by diet and space conditions. Environ. BioL Med. 1: 197, 1971. KRAMER, P. The meaning of high- and low-residue diets. Gastroenterology 47: 649, 1964. ROSE, W. C. Amino acid requirements of man. Federation Proc. 8: 546, 1949. ASSOCIATION OF OFFICIAL ANALYTICAL CHEMISTS. Official Methods of Analysis. Washington: Association of Official Analytical Chemists, 1970, p. 16. VAN DE KAMER, J. H., T. B. HUININK AND H. A. WEYERS. Rapid method for the determination of fat in feces. J. Biol. Chem. 177: 347, 1948.

Downloaded from https://academic.oup.com/ajcn/article-abstract/28/5/502/4732914 by East Carolina University user on 16 January 2019

levels

AL.