XII - 12th International Symposium - Digestive Physiology of Pigs

Digestive
Physiology
of Pigs
first 3 weeks post-weaning and induces compensatory
growth and improved feed efficiency thereafter. A study was
undertaken to explore physiological mechanisms involved
in compensatory growth following a nutritional insult. Fiftysix
pigs were weaned at 21 ± 2 d of age and fed high (H) or
low (L) complexity diets for 6 wk. All pigs received the same
grower diet thereafter. Pigs were killed at wk 2, 4, and 8
post-weaning and proximal jejunum and distal ileum were
sampled for evaluation of histology and enzyme activity. In
the proximal jejunum gut morphology was affected by diet
at wk 2 and 4, but not at wk 8. Villus height was lower (P =
0.03) at wk 2 in pigs on L than H (356 vs 427 μm) but not
different at wk 4 (527 vs 492 μm). There was no effect of
diet on crypt depth; villus height:crypt depth ratio increased
(P = 0.02) from wk 2 to wk 4 (2.1 vs 2.8) in pigs on L, but
was not changed (2.3 vs 2.5) in pigs on H. Diet did not
impact gut morphology at the distal ileum. Intestinal alkaline
phosphatase (IAP) substrate affinity (IAP Km ) was higher at
wk 2 than wk 4 or wk 8 (2.70 vs 1.65 or 1.84 mmol/L, P <
0.05) but was not affected by diet. Within week, maximal
specific activity of IAP (IAP Vmax ) was not affected by diet
but was higher at wk 2 than wk 4 (0.157 vs 0.134 μmol/mg
protein•min −1 , P < 0.005) in pigs on H and was not different
at wk 4 (0.154 vs 0.138 μmol/mg protein•min −1 , P = 0.17)
in pigs on L. IAP Vmax was higher at wk 2 than wk 8 (0.155
vs 0.137 μmol/mg protein•min −1 , P < 0.09) regardless of
diet. There was no effect of diet on IAP Vmax or IAP Km in the
ileum. Compensatory growth observed in pigs following
a nutritional insult after weaning may be due in part to
improvement in digestive capability.
Key words: digestive capability, nutritional insult, newly
weaned pigs
1127 Standardized ileal amino acid digestibility in
egg from hyperimmunized-hens fed to nursery pigs. J.
M. Heo,* E. Kiarie, R. Kahindi, T. A. Woyengo, and C. M.
Nyachoti, University of Manitoba, Winnipeg, MB, Canada.
The aim of the study was to determine the apparent (AID)
and standardized (SID) ileal AA digestibilities in whole egg
from hens hyperimmunized with E. coli K88 antigens (EGG)
fed to nursery pigs. Spray dried porcine plasma (SDPP)
was included for comparison. Eight barrows (Yorkshire-
Landrace × Duroc; initial BW = 17 ± 1 kg) fitted with a
T-cannula at the distal ileum were fed 2 diets in a completely
randomized design to give 4 observation per diet. The diets
were cornstarch-based with either EGG or SDPP as the
sole source of protein, and were formulated to contain 13%
CP. At the end of the study, a 5% casein diet was fed to all
pigs (n = 8) to quantify endogenous N and AA losses to
determine SID. Titanium dioxide (3 g/kg) was included in
the diets as an indigestible maker. Each period lasted for
7 d. Pigs were acclimatized to their respective diets for 5
d followed by 12 h of continuous ileal digesta collection on
d 6 and 7. Daily feed allowance was set a 4% BW at the
beginning of each period and offered in 2 equal portions at
08:00 and 16:00 h as a dry mash. Pigs had unlimited access
to water via low pressure nipple drinkers at all times. The
AID (%) of all measured AA and CP were lower (P < 0.05) in
EGG compared with SDPP. The SID (%) of CP (82 vs. 96),
Arg (80 vs. 100), His (71 vs. 94), Ile (75 vs. 95), Leu (74 vs.
XII INTERNATIONAL SYMPOSIUM ON
DIGESTIVE PHYSIOLOGY OF PIGS
87
Session II
94), Lys (71 vs. 95), Met (75 vs. 96), Phe (68 vs. 93), Thr
(74 vs. 91) and Val (74 vs. 93) for indispensable AA and Ala
(75 vs. 95), Asp (72 vs. 93), Cys (66 vs. 93), Glu (77 vs. 97),
Ser (68 vs. 96) and Tyr (66 vs. 89) for dispensable AA were
lower (P < 0.05) in pigs fed EGG compared with SDPP. The
average SID of indispensable AA between EGG and SDPP
was 73% and 95%, respectively, thus suggesting that the
SID of indispensable AA in EGG are approximately 23%
lower than in SDPP.
Key words: amino acid, digestibility, pig
1128 high-moisture airtight storage of barley and
wheat improves nutrient digestibility. H. D. Poulsen,* J.
V. Nørgaard, and K. Blaabjerg, Aarhus University, Department
of Animal Science, Foulum, P.O. Box 50, Tjele,
Denmark.
Barley (B) and wheat (W) are often stored dry at a humidity
not higher than 14%, which during rainy periods requires
that the grains are dried after harvest. However, it is
hypothesized that air tight storage of B and W with high
moisture contents will result in higher nutrient digestibility
due to chemical conversions taking place before feeding.
The objective of this study was to evaluate the effect of
high-moisture compared with dry storage of B and W on the
digestibility of phosphorus (P) and protein. The crops were
grown on the same field keeping all other factors constant.
Half of the grains was harvested in the morning after a rainy
day and stored in airtight silos (DM: B 85.2%; W 82.8%)
and the other half was harvested later the same day (windy
and sunny) and stored dry (DM: B 89.8%; W 88.3%).
After 6 mo of storage, a low and a high moisture diet was
prepared with a B:W ratio of 1:1 mixed with soybean meal
and rape seed cake to produce a normal compound diet
without inorganic P and microbial phytase. Sixteen pigs (45
kg) housed in metabolism crates were fed either the low
or the high moisture diet for 5 d for adaptation and 7 d for
total collection of feces. The P digestibility was 41 in the
low and 46% in the high-moisture diet (P < 0.01). Similarly,
the protein digestibility was 78 and 81% (P = 0.10). The
phytase activity of the dry was lower than the high-moisture
stored grain (870 vs. 990 FTU/kg DM). This suggests that
high-moisture storage of grain was superior in maintaining
the activity of phytase. Overall, the high-moisture storage
increased the digestibility of phosphorus and protein when
the grain was fed to finishing pigs. Thus, high-moisture air
tight storage saved energy (no drying) and at the same time
enhanced the availability of P and protein and improved
the nutritional value of grains probably through enzymatic
activity during storage.
Key words: high-moisture storage, phosphorus, protein
1129 Dose response of a new phytase on dry matter,
calcium and phosphorus digestibility in weaned piglets.
M. H. L. Bento* 1 , C. Pedersen 2 , P. W. Plumstead 1 , L.
Salmon 3,1 , C. M. Nyachoti 4 , and P. Bikker 5 , 1 Danisco Animal
Nutrition, Marlborough, Wiltshire, United Kingdom,
2 Livestock Feed Consultancy Ltd., Wilton, Wiltshire, United
Kingdom, 3 Premier Nutrition, Rugeley, Staffordshire, United
Kingdom, 4 University of Manitoba, Department of Animal