XII - 12th International Symposium - Digestive Physiology of Pigs

Digestive
Physiology
of Pigs
Key words: phytase, copper, zinc
1102 Copper induced reductions in cellular proliferation
and changes in membrane integrity in porcine
epithelial intestinal cells (IPEC-J2) and mouse macrophage
cells (RAW264.7). B. E. Aldridge* 1 , Y. Liu 2 , J. S.
Radcliffe 1 , and Y. Wang 2 , 1 Purdue University, Department of
Animal Science, West Lafayette, IN 47905, USA, 2 Zhejiang
University, Key Laboratory of Animal Nutrition and Feed
Science, Ministry of Agriculture, Institute of Feed Science,
Hangzhou 310058, Zhejiang, People’s Republic of China.
Current requirements of dietary Cu range from 3 to 6 ppm
Cu with industry feeding 25 ppm and growth promoting
levels fed between 125 and 250 ppm Cu. However, Cu
is potentially toxic to cells and little is known about levels
which may stimulate cell proliferation, or induce membrane
damage. The objective was to examine Cu-induced
cytotoxicity by measuring cell proliferation (WST1 assay)
and membrane integrity (LDH release assay) in mouse
macrophage (RAW264.7) and porcine epithelial intestinal
(IPEC-J2) cell lines. Cells were seeded at 1x10 5 cells/well
in 100 µL of culture medium and incubated for 12 h on a 96
well plate.IPEC-J2 and RAW264.7 cells were incubated in
duplicate or triplicate wells containing 5, 15, 25, 35, 45, 55
or 65 µg/ml of Cu from CuSO 4 , to measure LDH release (n
= 3 and n = 5, respectively). For the WST1 assay, IPEC-J2
and RAW264.7 cells were incubated in duplicate or triplicate
wells containing 1, 2, 4, 8, 16, 32, 64 and 128µg/ml Cu from
CuSO 4 (n = 4 and n = 3, respectively). The GLM procedure
of SAS was used to determine the effects of Cu, and linear
and quadratic contrasts were used to determine the dose
response to Cu. Plate run was the experimental unit.
Cellular proliferation quad decreased (P < 0.001) by a total
of 41 and 94% as Cu concentration increased from 1 to 128
µg/ml Cu in IPEC-J2 and RAW2564.7 cells, respectively.
Membrane damage (% cytotoxicity) in RAW264.7 cells (%
of Triton-X-100 control) linearly increased (P < 0.001) by
136% as Cu concentration increased from 5 to 65 µg/ml Cu
exposure. In contrast, LDH release in IPEC-J2 cells linearly
decreased (P < 0.001) as Cu concentration increased from
5 to 65 µg/ml, indicating a 71% decrease in membrane
damage. These data begin to elaborate on the potential
benefits (cell proliferation) and/or hazards (membrane
damage) of digestion and absorption of supplemental Cu in
various cells. In conclusion, increasing Cu in culture medium
for 12 h decreases cell proliferation in both macrophage
and intestinal cells, yet inversely affects membrane integrity
between cell lines.
Key words: IPEC-J2, RAW264.7, copper
1103 Metabolic profiling of plasma from sows before
parturition and during lactation. M. S. Hedemann 1 , C.
Flummer 1 , N. B. Kristensen 1,2 , and P. K. Theil* 1 , 1 Dept. of
Animal Science, Aarhus University, Foulum, DK-8830 Tjele,
Denmark, 2 Syddansk Kvæg, Billundvej 3, DK-6500 Vojens,
Denmark.
During transition, the sow undergoes large and sudden
metabolic changes to adapt from anabolic to catabolic
metabolism to produce milk. Little is known about changes
XII INTERNATIONAL SYMPOSIUM ON
DIGESTIVE PHYSIOLOGY OF PIGS
78
Session II
in nutrient uptake and intermediary metabolism during
this transition. This study was undertaken to screen the
metabolic profile for qualitative changes in nutrient uptake
and metabolism during transition. Four sows were fitted with
permanent catheters in artery femoralis (A), and in portal
(P) and hepatic (H) veins (sampling sites). Sows were fed a
standard lactation diet from 15 d before parturition for 42 d.
Blood samples were taken 1.5 h after feeding on d-10, d-3,
d3, and d17 relative to parturition and plasma metabolites
were analyzed by an LC-MS based approach using a
MicrO-TOF Q II mass spectrometer. Principal components
analysis was performed to visualize the metabolic profiles
and to screen for intermediary metabolites altered during
the transition period. The metabolic profile of sows on
d3 after parturition was distinct from other days. Plasma
betaine and 7 unidentified plasma lipid compounds
contributed to the separation on d3, and betaine was
lowered by 32% at d-3 compared with other time points (P
< 0.001). Plasma choline, 3 unidentified lipid compounds
and another metabolite contributed to the separation
due to sampling sites. Plasma choline was lowest in H
(25%), intermediate in A (39%) and highest in P (100%;
P < 0.001) plasma, indicating net absorption from the GItract
(P-A) and liver metabolism (H-P), while choline was
comparable among days (P = 0.33). Interactions between
day and sampling site were found for 2 unidentified lipid
compounds. The majority of unidentified metabolites (10 of
11) found using the loadings plot and affected by day or
sampling site or both were revealed as lipid compounds,
i.e., either bile acid-, cholesterol-, glycerol-, phosphatidyl -,
sphingomyelin-, or acylglycerol derivatives. In conclusion,
the intermediary metabolism of sows, especially the fat
metabolism, changed during the transition period, and a
deeper understanding and detection of involved metabolites
are necessary to optimize sow feeding during transition.
Key words: metabolites, pig, transition period
1104 Influence of high levels of dietary zinc oxide on
performance and small intestinal gene expression in
weaned piglets. L. Martin,* R. Pieper, W. Vahjen, and J.
Zentek, Institute of Animal Nutrition, Freie Universitaet Berlin,
Berlin, Germany.
High levels of dietary zinc oxide (ZnO) can enhance
performance and improve health of weaned piglets.
Besides an influence on intestinal microbial communities,
possible reasons could be an effect on digestion and
absorption. Whether short (one week) or longer (4 weeks)
ZnO supplementation has similar effects is still unclear.
This study investigated the effects of dietary ZnO fed to
piglets for 1, 2, 3, and 4 weeks after weaning. A total of
126 piglets weaned at 26 ± 1 d of age (7.6 ± 1.1 kg body
weight) were allocated into 3 groups fed 57 (low level), 164
(optimal level) or 2425 (high level) mg zinc/kg diet supplied
as analytical grade ZnO. After 1, 2, 3 and 4 weeks, 6 piglets
per group were euthanized and total mRNA was extracted
from jejunal tissue for gene expression analysis of lactasephlorizin
hydrolase (LPH), sucrase-isomaltase (SUC),
aminopeptidase-N (APN), intestinal alkaline phosphatase
(IAP), proliferating cell nuclear antigen (PCNA) and
caspase 3 (CASP). Activity of IAP was also determined in