XII - 12th International Symposium - Digestive Physiology of Pigs

Digestive
Physiology
of Pigs
The experiment comprised 36 pigs, 6 litters of 6 female
littermates weighing about 43 kg. From each litter, the pigs
were randomly assigned to the 6 treatments. The pigs were
housed in metabolism crates and fed one of the 6 diets
for 12 d, 5 d for adaptation and 7 d for total collection of
feces. Heat-treatment reduced the plant phytase activity
from 450 to 340 FTU/kg DM whereby the P digestibility
decreased (P ≤ 0.01) from 57 to 49% (without microbial
phytase). The added phytase increased (P ≤ 0.001) the P
digestibility to 60%, whether the diets were heat-treated or
not. Thus, the increase in the P digestibility by additions
of phytase was 8 percent units greater for heat-treated
compared with non-heat-treated diets. 500 FTU/kg as-fed
did not improve the P digestibility further compared with 250
FTU/kg as-fed. The phytase supplementation increased
(P ≤ 0.001) the digestible P content with 0.2 and 0.4 g/kg
as-fed diet in the non-heat-treated and heat-treated diets,
respectively. In conclusion, microbial phytase increased
the P digestibility to a maximum of 60% independent of
processing, but the magnitude of the increase was greater
in heat-treated compared with non-heat-treated diets
showing that assessments of effects of microbial phytases
on the P digestibility depend on the processing of the diet.
Thus, steam pelleting of feed should be considered when
supplementing phytase to avoid over- or underestimation of
the effect of microbial phytase.
Key words: phosphorus, phytase, heat-treatment
1108 environmental consequences of feeding high
fiber diet to growing pigs. A. Woldeghebriel* 1 , S. Smith 1 ,
T. Barios 1 , B. Pope 1 , and S. Gebrelul 2 , 1 North Carolina A&T
State University, Greensboro, NC, USA, 2 Southern University,
Baton Rouge, LA 70809.
The study was conducted to estimate the concentration of
carbon dioxide (CO 2 ) and methane (CH 4 ) in pigs using a
ruminant animal model currently under validation using CO 2
and CH 4 analyzer. Pigs were randomly assigned to pens (6/
pen) and pens assigned to 1 of 4 diets (4/diet). Diets include
a corn-soybean meal based diet as the control (CON, 8.3%
NDF), and 3 high fiber diets (D1, D2 and D3; 23.3, 23.9
and 20.0% NDF, respectively) each containing 5% sugar
beet pulp and an oats to barley ratios of 1:2, 1:1, and 2:1,
respectively. Diets contain similar amount of protein (18%
CP) and energy (3.415 Mcal/kg of feed). Pigs had free
access to their diets for 70 d. Three pigs of comparable
weights from each treatment were selected and kept without
feed for 18 h (abattoir requires overnight fasting) before
slaughter. Digesta samples from the stomach, cecum, and
colon were taken for the determination of short chain fatty
acid (SCFA) concentration and values obtained were used
to predict CO 2 and CH 4 concentration. Data collected were
analyzed using SAS Glimmix procedure, where animals
were considered random effects, and diet means were used
to compare treatment effects. The highest (P < 0.05) total
and individual SCFA concentration (except isobutyrate)
was found in pigs fed D3 and CON diets. The average
molar concentration of isobutyrate in pigs fed high fiber
diets was lower (31%; P < 0.05) than CON diet fed pigs.
Similarly, pigs fed high fiber diets on the average were 25.6
and 24.2% lower (P < 0.05) in CO 2 and CH 4 concentrations
XII INTERNATIONAL SYMPOSIUM ON
DIGESTIVE PHYSIOLOGY OF PIGS
80
Session II
respectively, compared with pigs fed CON diet. Pigs fed
the highest oats to barley ratio showed higher (P < 0.05)
concentrations of CO 2 , (8.3%) and CH 4 (5.1%) compare
with the averages of CO 2 (5.3%) and CH 4 (3.3%) in the
lower oats to barley ratios. Molar proportions of SCFA,
CO 2 and CH 4 in gut contents were in the order of SCFA >
CO 2 , > CH4, at 53.0%, 28.6% and 18.4%, respectively and
CO 2 , and CH 4 were 47% of the total volume of gas in the
digestive tract of the pigs.
Key words: methane, carbon dixide, short-chain fatty acids
1109 The effect of live yeast utilization and dietary
fibre on growth performance, nutrient utilization and
gut microbiology in the weaning pig. R. Lizardo* 1 , A.
Perez-Vendrell 1 , I. Badiola 3 , R. D’Inca 2 , E. Auclair 2 , and J.
Brufau 1 , 1 IRTA - Institut de Recerca i Tecnologia Agroalimentaries,
Constantí, Tarragona, Spain, 2 LFA - Lesaffre
Feed Additives, Marquette-Lez-Lille, France, 3 CReSA -
Centre de Recerca en Sanitat Animal, Bellaterra, Barcelona,
spain.
The digestive microflora of piglets undergoes major
changes after weaning. Since the EU ban of antimicrobial
growth promoters, inclusion of live yeasts in diets became
usual due to their probiotic effects. Moreover, due to
increasing availability of cereal fiber-rich by-products,
swine feeds tend to contain more fiber, even for piglets.
Information on the use of live yeast on high-fiber diets is
lacking. In total, 144 weaning piglets were distributed in a
2x2 factorial arrangement. Treatments correspond to low
and high fiber diets (11.3 vs 13.8% NDF) supplemented
or not with 5*10 9 cfu/kg of live Saccharomyces cerevisiae
Sc47 yeasts (Actisaf). Wheat bran was used as the
additional fiber source. Productive parameters were
evaluated after 5 weeks. Then, 32 piglets were slaughtered
and cecum content was sampled for VFA determinations
and gut microbiology. In a 2nd similar trial, 36 piglets of
around 15-kg were used for digestibility measurements
using celite as indigestible marker. During the 1st 2 weeks
after weaning, effects were not observed. However, during
the subsequent 3 weeks, piglets fed low fiber and those
fed yeast diets consumed more feed (P < 0.05) and tended
to gain more weight (P = 0.08). A synergistic association
of yeast and high-fiber diets is also observed for overall
daily weight gain (P < 0.05) and final liveweight (P = 0.08).
Nitrogen (P = 0.08), NDF and ADF digestibility (P < 0.05)
increased with fiber level whereas that of dry matter,
nitrogen (P < 0.05), energy (P = 0.10), NDF and ADF (P <
0.01) increased with yeast inclusion in diets. Although some
tendencies were observed only acetate concentration was
increased with both fiber level and inclusion of yeast (57.4,
60.6; P < 0.01). Dendograms of the similarity degree of
RFLP profiles of intestinal microbiota clearly indicated the
existence of clusters related with diets in cecum content
but not in feces. In conclusion, utilization of live yeast in
high fiber diets may influence the digestive environment
affecting nutrient digestion and piglet productive variables
after weaning.
Key words: piglet, live yeast, digestion