XII - 12th International Symposium - Digestive Physiology of Pigs

Digestive
Physiology
of Pigs
jejunal brush border membranes. Data were analyzed by
ANOVA following LSD post-hoc test using SPSS (version
19.0). Average daily gain (22 and 25%) and feed intake
(23 and 24%) were higher (P < 0.05) in piglets fed high
vs. the 2 other ZnO levels during the first week, but did not
differ thereafter. Gene expression analysis did not reveal
clear effects of dietary zinc level on transcript abundance
for digestive enzymes (LPH, SUC, APN), markers for cell
turnover (PCNA, CASP) and IAP. However, the activity
of IAP was 39 and 50% higher (P < 0.05) in piglets fed
high vs. the 2 other ZnO levels. In conclusion, high dietary
levels of zinc from ZnO can increase early post-weaning
performance but this cannot be clearly linked to intestinal
expression and activity of digestive enzymes.
Key words: zinc oxide, performance, gene expression
1105 Pharmacological levels of zinc oxide change the
expression of zinc transport proteins zIP4 and znT1
and metallothionein but not DMT 1 and znT2 in the jejunum
of weaned piglets. R. Pieper,* L. Martin, W. Vahjen,
and J. Zentek, Institute of Animal Nutrition, Freie Universitaet
Berlin, Berlin, Germany.
Intestinal zinc uptake is facilitated through members of
zinc transporter families SLC30 (ZnT) and SLC39 (ZIP). In
rodents, low or adequate zinc supply alters regulation of
these transporters; however, such mechanisms are unclear
for pigs. Fifty-four piglets were fed diets containing 57 (low),
164 (optimal) or 2425 (high) mg/kg DM dietary zinc. The
zinc level was adjusted using analytical grade zinc oxide
(Sigma). After 4 weeks, 30 animals (10 per group) were
euthanized and jejunal tissues were sampled for mRNA
extraction. Primers for zinc transporters ZnT1, ZnT2, ZIP4,
divalent metal transporter 1 DMT1 and metallothionein (MT)
were generated using public available gene sequences.
Data were analyzed by ANOVA following post-hoc Tukeytest
using SPSS 19.0. The zinc concentration in jejunal
contents increased (P < 0.05) with increasing dietary
zinc (550 ± 54, 647 ± 110 and 8178 ± 839 mg/kg for low,
optimal and high supplemented groups, respectively).
Increasing intestinal zinc concentration increased (P <
0.05) expression of ZnT1 (0.59, 0.65 and 0.88, for low,
optimal and high supplemented groups, respectively)
and decreased (P < 0.05) expression of ZIP4 (1.78, 1.63
and 0.92 for low, optimal and high supplemented groups,
respectively), whereas expression of ZnT2 and DMT1
were not affected. High levels of dietary and intestinal zinc
increased the expression of MT (0.87, 0.95 and 1.74 for
low, optimal and high supplemented groups, respectively).
In conclusion, high levels of dietary and intestinal zinc
can influence the expression of zinc transporters ZIP4
and ZnT1 and increase the expression of MT. Thus, high
dietary zinc concentrations increase intracellular zinc,
promote increased zinc export from intestinal tissues into
extracellular compartments and decrease the zinc uptake
from the gut lumen.
Key words: zinc oxide, zinc transport, absorption
1106 Ileal digestibility of soybean meal, sunflower
meal, pea, rape seed cake and lupine in pigs. J. V.
XII INTERNATIONAL SYMPOSIUM ON
DIGESTIVE PHYSIOLOGY OF PIGS
79
Session II
Nørgaard,* J. A. Fernández, and H. Jørgensen, Dept. of
Animal Science, Aarhus University Foulum, Tjele, Denmark.
The use of European-grown protein sources is an important
factor in organic pig production, since only organically
produced feedstuffs are allowed from 2012. Especially pea,
rape seed cake, and lupine are interesting, because they
can also be produced in Northern Europe. The objective of
this experiment was therefore to ascertain the standardized
ileal digestibility (SID) of protein and amino acids in
soybean meal, sunflower meal, rape seed cake, field pea
(Pisum sativum), and lupine (Lupinus angustifolius), with
508, 417, 356, 244 and 316 g crude protein/kg dry matter,
respectively. Pigs were fitted with either a T-cannula or a
steered ileo-cecal valve (SICV)-cannula. After surgery at
35 kg, pigs were allowed to recover for 14 d. Diets were
formulated to contain from 170 to 186 g crude protein/kg
dry matter by diluting the test feedstuffs with a N-free diet
based on wheat starch and sugar. Endogenous losses of
protein (15.1 g/kg DM) and amino acids were estimated
by feeding the N-free diet. Diets were supplemented with
both chromic oxide and titanium oxide as indigestible
markers. Results are presented as means across type of
cannula and marker. Soybean meal, sunflower meal, rape
seed cake, and pea were evaluated in 10 pigs and lupine
in 7 pigs. The apparent digestibility of organic matter in
soybean meal (80%) was greater (P < 0.05) compared
with sunflower meal (71%) and rape seed cake (71%), but
not different than pea (76%). Lupine had the lowest (P <
0.05) with 64% apparent organic matter digestibility. The
SID of crude protein was 85% for soybean meal, 77% for
sunflower meal, 78% for rape seed cake, 89% for pea, and
79% for lupine, with greater SID for soybean meal and pea
compared with sunflower meal, rape seed cake and lupine
(P < 0.05). Sunflower meal had lowest (P < 0.05) SID for
lysine and histidine, and lupine had lowest (P < 0.05) SID
for methionine and valine. These results imply soybean
meal and pea to be high-digestible protein source relative
to sunflower meal, rape seed cake, and especially lupine,
although all tested feedstuffs seem appropriate for inclusion
in diets for organic pigs.
Key words: amino acids, protein, standardized ileal
digestibility
1107 effect of microbial phytase on phosphorus
digestibility in non-heat-treated and heat-treated
wheat-barley pig diets. K. Blaabjerg,* J. V. Nørgaard, and
H. D. Poulsen, Aarhus University, Faculty of Science and
Technology, Department of Animal Science, P.O. Box 50,
8830 Tjele, Denmark.
Microbial phytase increases the digestibility of phytate
phosphorus (P) resulting in reduced need for feed phosphate
and improved P utilization. The effect of microbial phytase
on the P digestibility may depend on the processing of the
feed due to inactivation of plant phytase. A wheat-barley
diet without feed phosphate was ground and half of the
batch was steam-pelleted at approximately 81°C and
crumbled. Subsequently, both non-heat-treated and heattreated
diets were divided in 3 portions and phytase was
added at 0, 250 and 500 FTU/kg as-fed (Aspergillus niger).