The influence of soy oligosaccharides on apparent and true ileal amino acid digestibilities and fecal consistency in growing pigs.

Fourteen ileally cannulated pigs (BW = 35 +/- 2 kg) were randomly allotted to a replicated 7 x 7 Latin square design experiment to evaluate the influence of the soybean oligosaccharides (OS), raffinose and stachyose, on ileal nutrient digestibility and fecal consistency. Semipurified diets containing soy protein concentrate (SPC) or soybean meal (SBM) as the sole protein sources were fed. Soy solubles (SS), a by-product of SBM processing containing 3.5% raffinose and 11.5% stachyose, were used to increase dietary raffinose and stachyose concentrations. The seven dietary treatments were SPC, SPC + 9% SS, SBM, SBM + 9% SS, SBM + 18% SS, SBM + 24,000 U alpha-galactosidase enzyme preparation/kg diet, and a low-protein casein (LPC) diet used to calculate true digestibility. Diets, with the exception of the LPC diet, were formulated to contain 17% CP. All diets contained 0.5% chromic oxide as a marker for ileal digestibility determination. The experimental periods were divided into a 5-d diet adaptation followed by 2-d of ileal digesta collection. Diets and digesta were analyzed for DM, N, Cr, amino acids (AA), raffinose, and stachyose. Fecal consistency was determined on d 6 and 7 of each experimental period. The apparent and true ileal AA digestibilities were not different (P < 0.05) for the SPC and SBM control diets. When SS was added to the SPC diet, apparent and true N and AA digestibilities were depressed (P < 0.05) with the exception of Trp and Pro. The apparent and true ileal N and AA digestibilities were not different (P > 0.05) between the SBM control and SBM + 9% SS diets with the exception of Glu. There was a linear decrease (P < 0.05) in apparent and true DM, Val, Gly, and Tyr digestibilities when increasing levels of SS were added to the SBM diet. The addition of alpha-galactosidase did not improve apparent or true ileal N or AA digestibilities except for apparent and true Val and Tyr. Ileal raffinose digestibility was improved (P < 0.05) by addition of a-galactosidase, but was not affected by any other dietary treatment. Ileal stachyose digestibility was not affected (P > 0.58) by treatment. Fecal consistency likewise was not affected (P > 0.36) by dietary treatment. In conclusion, soy OS reduced nutrient digestibilities, but the reductions were small, ranging from approximately 1.1 to 7.4 percentage units. This suggests that other factors may be negatively impacting SBM digestibility.

Improved procedure and cannula design for simple-T cannulation at the distal ileum in growing pigs.

Inserting a device (cannula) into the ileum is a common technique for studying nutrient digestibility, determining the disappearance or synthesis of a component, live tissue sampling, and inserting compounds or therapeutic agents into a specific region of the gastrointestinal tract. The purpose of this study was to implement improved cannulation procedures and care and management practices for cannulated pigs. Using these improved procedures, we successfully cannulated and maintained 15 pigs, each with an initial body weight of 30 kg. The newly designed cannula afforded improved stability and ease of adjustment while providing increased comfort to the pigs. The cannula was exteriorized through the last two ribs, providing excellent stability and security. To increase pig comfort, the cannulation site was washed and dried thoroughly and ointment was applied to the skin twice daily throughout the 63-day experiment. These updated procedures and maintenance practices should be considered and implemented in future experiments involving intestinal cannulation in pigs.

The effect of feed intake on ileal rate of passage and apparent amino acid digestibility determined with or without correction factors in pigs.

The apparent ileal digestibilities of amino acids and rate of passage were evaluated in pigs (BW = 78.3 +/- 7.4 kg) fed a semipurified diet. The pigs were fed 1.82, 2.73, or 3.65 kg DMI/d. The highest level of feed intake was considered to be ad libitum feeding. The pigs were fed according to a 3 x 3 Latin square design and were allowed to adapt to each experimental diet for 5 d. This was followed by 1 d of continuous collection of ileal digesta and a 2nd d of continuous collection separated into six 2-h postprandial time blocks. Ytterbium chloride hexahydrate was used to determine rate of passage. The ileal digestibilities of amino acids and rate of passage were unaffected (P > 0.05) by level of feed intake. The use of correction factors to more accurately express amino acid concentrations in the diet and digesta affected (P < 0.05) the apparent ileal digestibility coefficients of some amino acids.