Effects of feed intake and dietary nutrient density on apparent ileal and total tract digestibility of nutrients and gross energy for growing pigs1

Abstract

The present study was conducted to investigate the effects of feed intake (FI) and dietary nutrient concentration on the determination of apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients and GE for growing pigs. A total of 48 growing pigs (40.7 ± 1.3 kg initial BW) were surgically fitted with simple T-cannulas at the distal ileum and assigned to 6 treatment groups in a 2 × 3 factorial arrangement of 2 diets (a low-nutrient-density [LND] diet or a normal-nutrient-density [NND] diet) and 3 FI levels (3, 4 or 5% of BW per day). The experimental period consisted of a 5-d adjustment period: 2 d of feces collection (on d 6 and 7), and 2 d of ileal digesta collection on (d 8 and 9). Chromic oxide was used as an indigestible marker to calculate AID of AA and AID and ATTD of CP, ether extract (EE), ash, ADF, NDF, total carbohydrates (CHO), and GE. The AID of CP ( < 0.05), EE ( < 0.1), ash ( < 0.05), and GE ( < 0.1); the ATTD of ash ( < 0.1); and the hindgut disappearance of CP ( < 0.05), ash ( < 0.1), and most AA were affected by the interaction of dietary nutrient density and FI level. The AID of CP and the AID and ATTD of DM, EE, CHO, and GE linearly decreased for pigs fed a NND diet as FI increased ( < 0.05). Furthermore, the AID of CHO ( < 0.1) and NDF ( < 0.05), the ATTD of DM ( < 0.1), and the hindgut disappearance of CHO and NDF ( < 0.1) were influenced by FI. When pigs were fed the NND diet, the AID of most AA decreased (linear, < 0.05) with increasing FI. However, there were no linear or quadratic effects of FI levels on the AID, ATTD, and the hindgut disappearance of DM, CP, EE, CHO, NDF, ADF, and GE and the AID of most AA for pigs fed the LND diet. In summary, the AID and ATTD of nutrients and GE response of growing pigs to FI levels are dependent on dietary nutrients density. The AID and ATTD of nutrients and GE decreased for pigs fed the NND diet as FI increased.

Comparative energy digestibility of protein feed ingredients in crossbred barrows in different growing stages

“…The different feed intakes may be a possible reason for the different effects of BW on the ATTD of nutrients (Shi and Noblet 1993;Morel et al 2006;Liu et al 2016). In addition, it was reported that the small intestine of pigs is almost fully developed at 20 kg BW, while the hindgut is still growing at 150 kg BW (Morel et al 2006).…”

Net absorption and liver metabolism of amino acids and heat production of portal-drained viscera and liver in multiparous sows during transition and lactation

“…One possible reason is that the enhanced feed intake led to a faster passage rate in the gastrointestinal tract, allowing less time for fermentation in the hindgut, thus reducing the digestibility of all nutrients and energy [29]. Another possible explanation could be that the influence of endogenous excretions may be changed according to feeding levels [30]. However, other researchers observed no differences of ATTD of energy and nutrients in response to feeding levels [31,32], while Dourmad and coworkers even found that ATTD of DM, organic matter, and GE increased linearly with the increase of energy intake [33].…”

Effects of Collection Durations on the Determination of Energy Values and Nutrient Digestibility of High-Fiber Diets in Growing Pigs by Total Fecal Collection Method

“…The organic matter (OM, %) content in the ingredients, diets, and feces was calculated as the difference between DM (%) and ash (%). The concentration of total carbohydrates (CHO, %) in the diets and feces was calculated according to the following equation (CHO = DM − CP − EE − ash) [38]. Neutral detergent fiber (NDF) and acid detergent fiber (ADF) were determined using filter bags and fiber analyzer equipment (Fiber Analyzer; ANKOM Technology, Macedon, NY, USA) following a modification of the procedures [39].…”