XII - 12th International Symposium - Digestive Physiology of Pigs

Digestive
Physiology
of Pigs
Hannover, Germany, 2 Abbott Products GmbH (Germany),
Hannover, Germany.
The pancreatic duct ligated minipig (PL) is an established
model of exocrine pancreatic insufficiency (EPI), but can
also be used as a model for studying effects of reduced
prececal nutrient digestibility. The EPI distinctly reduces
prececal digestion and absorption of nutrients with diverse
consequences. This study was conducted to quantify
endogenous N losses (ileocecal flux and fecal losses) in
PL pigs and healthy controls (C) fed a N-free diet. Eight
Göttinger minipigs (mean bw: ~30 kg) were fitted with an
ileo-cecal re-entrant fistula. In 4 pigs the pancreatic duct
was ligated (PL) to induce EPI. The diet fed was almost
N-free [maize starch (88.8%), soy oil (4%), methylcellulose
(4%) and minerals] with a crude protein content (cp) of
0.3%. 250 g of the diet was fed twice a day ( = 447 g dry
matter (DM)/day) beginning in the morning when chyme
or feces collection started. Ileal chyme was collected over
12 h for 7 d (except d 6). In a second study feces were
collected for 10 d. In PL pigs the amount of collected chyme
was much higher than in C (P ≤ 0.05). Also DM content of
chyme was higher (P ≤ 0.05) in PL. Cp content of chyme
did not differ. Basal ileocecal cp flux (g/kg DM intake) was
higher (P ≤ 0.05) in PL (41.3 ± 11.1) than in C (15.0 ± 5.52).
The amount of feces did not differ but cp-losses via feces
were higher in PL (P ≤ 0.05). Lowest fecal endogenous cp
losses (g/kg DM intake) were ~2.5 times higher in PL (20.6
± 10.6) than in C (7.10 ± 3.94). In C endogenous N losses
were comparable with those of other studies (prc. 15; total
tract: 7.10 g cp / kg DM intake), while those in PL-pigs
were 2 to 3 times higher. In conclusion, the pancreatic duct
ligation reduces DM digestibility and increases endogenous
N-losses. These unexpected findings (loss of pancreatic
secretion was expected to lower endogenous losses)
indicate, that the effect of increase of chyme mass is the
predominate factor.
Key words: endogenous losses, crude protein, EPI
1059 Effect of highly insoluble, low fermentable fiber
on energy, fiber, and amino acid digestibility and on
hindgut fermentation of fiber in growing pigs. N. A.
Gutierrez* 1 , B. J. Kerr 2 , and J. F. Patience 1 , 1 Iowa State
University, Ames, IA, USA, 2 USDA-ARS, Ames, IA, USA.
An experiment was conducted to determine the effect of
increasing amounts of highly insoluble, low fermentable
fiber from corn bran on digestibility of energy, fiber, and
AA, and on hindgut fermentation of fiber. A total of 15
growing pigs (initial BW: 28.7 ± 2.1 kg BW) were fitted
with a T-cannula in the distal ileum and allotted to 5 dietary
treatment groups in a 3-period incomplete block design with
9 observations per treatment. Treatments included a corncasein
basal diet and 4 diets containing increasing levels
of corn bran with solubles (26.5% total dietary fiber, TDF):
10, 20, 30 and 40%. The TDF content of treatments was
7.3, 8.7, 9.1, 11.4, and 14.7% (as-fed basis). Corn or corn
bran were the only sources of dietary fiber, and SID Lys:ME
was maintained at 2.6 g/Mcal of ME across treatments.
Feed was provided at 90% of predicted ad libitum intake
of the basal diet. Hindgut fermentation of energy and fiber
XII INTERNATIONAL SYMPOSIUM ON
DIGESTIVE PHYSIOLOGY OF PIGS
62
Session II
were determined by difference between apparent total tract
digestibility (ATTD) and apparent ileal digestibility (AID) of
GE, TDF and NDF. The AID of AA was also calculated. Ileal
and total tract flow of DM, GE, TDF and NDF increased
(linear, P < 0.001) with dietary fiber level. The AID of GE
(78.8 vs. 72.2%) decreased (linear, P < 0.001), but the
AID of TDF (14.9 vs. 19.9%) and NDF (23.0 vs. 25.2%)
were not affected (P = 0.15 and P = 0.76, respectively) by
dietary fiber level. The ATTD of GE (85.4 vs. 76.9%), TDF
(36.6 vs. 29.1%), and NDF (42.6 vs. 30.5%) decreased
(linear, P < 0.001) with dietary fiber level. The hindgut
fermentation of NDF (19.6% vs. 5.9%) and TDF (21.9 vs.
9.7%) decreased linearly (P < 0.001), and GE (6.5 vs 4.8%)
tended to decrease (linear, P = 0.07) with dietary fiber level.
The AID of indispensable AA (84.3 vs. 78.9%, mean value)
and of Asp, Glu and Tyr decreased (linear, P < 0.001) with
dietary fiber level. In conclusion, increasing levels of highly
insoluble and low fermentable fiber of cornorigin reaching
the hindgut may reduce the growing pig′s ability to ferment
the fiber component of the diet, and may also decrease the
digestibility of dietary AA.
Key words: insoluble fiber, dietary fiber, pigs
1060 Lactose in diet influences the degradation of
mixed linked β-D-glucan in the small intestine of pigs.
K. E. B. Knudsen,* Aarhus University, Blichers Alle 20,
8830 Tjele, Denmark.
The present study was undertaken to study the cause for
the variation in the digestibility of mixed linked β(1–3;1–
4)-D-glucan (β-glucan) in the small intestine of growing
pigs. Β-glucan is an important cell wall (dietary fiber, DF)
component of the endosperm of barley and oats. The
digestibility of β-glucan in the small intestine from both
cereals is among the highest of all DF components, but
in one particular study with oat-based diets it was lower
(P < 0.001) than what was found in other studies. In this
study, whey protein containing lactose was used as protein
supplement. Lactose is slowly digestible in the small
intestine. To investigate if lactose could be causative for
the lower digestibility of β-glucan in the study with whey
protein, it was decided to quantify the content of lactose
in the diets and to analyze for lactose in digesta samples
from the small intestine (the small intestine was divided in
3 by length equal segments: SI1, SI2, SI3) and ileal digesta
along with parameters for organic acids (lactic acids and
short-chain fatty acids). Diets containing lactose were
based on oat goats, oat flour, and oat bran (lactose 1.2–
3.8% of DM), whereas the reference diets were based on
rolled oats, rolled oats and oat bran, wheat flour with added
oat bran and wheat flour with added β-glucan (lactose
0–0.1% of DM). Lactose was identified in digesta up to SI2,
but disappeared in digesta from SI3 and the ileum. There
was no difference in the digestibility of β-glucan among
diets up to SI3 (mean 18%), whereas the digestibility in
ileum was 66% in diets without lactose and 27% in diets
containing lactose (P < 0.001). With all diets, β-glucan was
virtually completely digested in the cecum (mean 96%). No
difference was found in the concentration of organic acids
between diets either in SI3, ileum or cecum. In conclusion,
slowly digestible lactose was the most likely cause of the