XII - 12th International Symposium - Digestive Physiology of Pigs

Digestive
Physiology
of Pigs
Gut maturation during suckling and after weaning is
influenced by maternal environment. Scarce is the
knowledge on the presence and the regulation of taste
receptors in the pig gastro-intestinal tract. The same is for
the machinery that processes the taste signals, including
α-transducin. Our main goal was to assess if the age of
offspring and maternal environment, as influenced by a
maternal antibiotic treatment, could affect the expression
of the receptors for umami and sweet taste in offspring
stomach. Eighty 4 pigs reared from sows fed a diet with or
without Amoxicillin (40 mg/kg BW/d, on −10 d to +21 d from
farrowing, ATB) were sacrificed at 14 d, 21 d, 28 d (weaning)
or 42 d, and sampled for oxyntic (OXY) and pyloric mucosa
(PY). In PY, gene expression (RT Real-Time PCR, corrected
for 2 housekeeping genes) for TAS1R3 (necessary for sweet
and umami taste) was stable in time and not affected by
ATB. TAS1R1 (complementary for umami) increased from
suckling to post-weaning period (P = 0.001), and was lower
in ATB offspring (P = 0.013). TAS1R2 (complementary for
sweet) gene expression was not detected. TAS1R1 gene
expression in OXY, increased with age in suckling period
(P = 0.013), but not later. Transducin gene expression in
PY was higher in ATB offspring (P = 0.043); the number
of cells staining for transducin per gland in PY decreased
during the suckling and post-weaning periods (P < 0.001),
while cell counts tended to be lower in ATB offspring (P =
0.092). TAS1R1 and TAS1R3 gene expression in PY was
also tested in littermate offspring that were reared up to the
age of 5 mo, and then kept on the same diet (low fat, 2%)
or switched to a high fat (11%) diet for 4 weeks (n = 10
pigs per group). Neither perinatal ATB treatment nor later
fat diet content affected the studied variables. Data show
that sensing for umami taste has relevance for 2 different
gastric mucosae. It can change with age and be potentially
affected by maternal environment. For α-transducin,
divergent observations on gene expression and positive
cell counts require further evaluation.
Key words: umami, sow environment, taste
3009 effects of supplemental zinc amino acid complex
on intestinal integrity in heat-stressed pigs. M. V.
Sanz-Fernandez* 1 , S. C. Pearce 1 , V. Mani 1 , N. K. Gabler 1 ,
J. F. Patience 1 , M. E. Wilson 2 , M. T. Socha 2 , R. P. Rhoads 3 ,
and L. H. Baumgard 1 , 1 Iowa State University, Ames, IA,
USA, 2 Zinpro Corporation, Eden Prairie, MN, USA, 3 Virginia
Polytechnic Institute and State University, Blacksburg, VA,
USA.
Heat stress (HS) reduces livestock productivity and this
may in part be mediated by reduced intestinal integrity or
“leaky gut.” Zinc improves intestinal integrity in a variety
of human and small animal models. Consequently, we
hypothesized that zinc amino acid complex (ZnAA) would
mitigate HS-induced leaky gut in pigs. Crossbred gilts (43
± 6 kg BW) were ad libitum fed 1 of 3 diets: 1) control (120
ppm ZnSO 4 ; n = 29), 2) control + 100 ppm ZnAA from Availa
Zn (Zn220; Zinpro Corporation; n = 14), and 3) control +
200 ppm ZnAA from Availa Zn (Zn320; n = 16). After 25d
on experimental diets, half of the controls (n = 13), and
all Zn220 and Zn320-fed pigs were exposed to constant
HS conditions (36°C, ≈50% RH) and fed ad libitum. To
XII INTERNATIONAL SYMPOSIUM ON
DIGESTIVE PHYSIOLOGY OF PIGS
119
Session V
eliminate the confounding effects of dissimilar feed intake,
16 control pigs remained in thermo-neutral (TN) conditions
(19°C, ≈61% RH) and were pair-fed (PF) to the HS pigs.
After either 1 or 7d of environmental exposure, pigs from
each dietary treatment were euthanized and fresh ileum
and colon sections were isolated and mounted into modified
Ussing chambers. Intestinal permeability was assessed via
measures of transepithelial electrical resistance (TER) and
apparent permeability coefficients (APP) for fluorescein
isothiocyanate-labeled (FITC) lipopolysaccharide (LPS)
and the macromolecule FITC-dextran. As HS progressed,
both ileal and colonic TER decreased (P ≤ 0.01; 31 and
17%, respectively). This was mirrored by an increase in
ileal and colonic FITC-dextran APP with time (P ≤ 0.01; 15
and 6 fold, respectively). Colonic FITC-LPS APP tended to
increase (P ≤ 0.10; 106%) from d1 to 7, but did not differ
between treatments. There was a quadratic response (P =
0.02) to increasing ZnAA on ileal TER, as it was improved
(P ≤ 0.05; 57%) in Zn220-fed pigs compared with control
HS pigs. This was paralleled with a weak (P = 0.13)
quadratic decrease in ileal FITC-dextran APP for Zn220fed
pigs compared with controls and Zn320-fed pigs. These
data demonstrate that supplementing ZnAA at the Zn220
dose improves small intestinal integrity during severe HS.
Key words: heat stress, zinc amino acid complex, intestine
3010 The effect of feeding genetically modified Bt
MON810 maize to sows during first gestation and
lactation on maternal and offspring health. M. C.
Walsh 1 , S. G. Buzoianu 1,2 , G. E. Gardiner 2 , M. C. Rea 3 , O.
O’Donovan 2 , R. P. Ross 3 , and P. G. Lawlor* 1 , 1 Teagasc, Pig
Development Department,, Moorepark, Fermoy, Co. Cork
Ireland, 2 Waterford Institute of Technology, Waterford, Ireland,
3 Teagasc, Food Research Centre, Moorepark, Fermoy,
Co. Cork, Ireland.
The objective of this research was to examine the transgenerational
effects of feeding Bt MON810 maize on
maternal and offspring health in pigs. Sows (n = 24) were
fed Bt or isogenic maize diets from service to the end of
lactation. Back-fat depth and BW were recorded at service,
on d 56 and 110 of gestation and on d 28 of lactation and
blood samples were taken for hematological and serum
biochemical analyses. The number of piglets born alive,
stillborn and weaned per litter was recorded. Individual
piglet BW (n = 24) was recorded at birth and weaning and
ADG was calculated for the suckling period. The fourth
piglet born alive was sacrificed, organs were weighed
and blood samples were taken for serum biochemical and
hematological analyses. Bt maize-fed sows were heavier
on d 56 of gestation (P < 0.05). Offspring from sows fed
isogenic maize tended to be heavier at weaning (P = 0.08)
but not at birth and there was no difference in ADG. Sows
fed Bt maize tended to have lower serum total protein (P =
0.10) and gamma glutamyl transferase on d 28 of lactation
(P = 0.06) and higher serum creatinine (P < 0.05). Serum
urea tended to be lower in Bt maize-fed sows on d 110
of gestation (P = 0.10) and in their offspring at birth (P =
0.08). Sow hemogloblin (P = 0.06) and hematocrit (P =
0.10) tended to be decreased in response to feeding Bt
maize and erythrocyte count was lower (P < 0.01). Mean