Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

The effects of physical form of a weaner diet on the gut integrity in weaned piglets

Litters weaned under commercial conditions undergo drastic social changes such as terminated access to sow's milk, transport to new pens, mixing with foreign litters, access to unfamiliar feeds (dry/slurry) and water nipples. This is manifested by apathy or aggression, no or little interest in new feed intake, growth check, and greater mortality. It is speculated that solid pellets are less preferably consumed than slurry (particularly in the first week after weaning), and it may lead to villous atrophy, reduced gut integrity, and increased pro-inflammatory cytokine expression.

Therefore, we studied the effects of an isocaloric weaner diet fed either as dry pellets or slurry (1:2.5 wt/vol) on the in vitro gut permeability, morphology and pro-inflammatory cytokines with 30 crossbred piglets. They were weaned at 28 days of age and fed over 7 days with gradually increasing daily rations, i.e., from 0.5x maintenance requirements (MR) for NE at weaning to 2.0xMR for NE at day 5 post-weaning.

The samples of proximal and mid jejunum were obtained at weaning (n=6), on day 3 (n=12) and on day 7 post-weaning (n=12) to measure villous height and crypt depth, mRNA expression level of interleukin 8, and permeability in Using chambers (via unidirectional flux of 14C-GlySar and 3H-mannitol as markers for trans- and paracellular transport, respectively). Piglets fed dry pellets had significantly greater (P<0.05) transcellular transport compared to those fed slurry. Paracellular transport and morphology (the villous length and crypt depth) were similar for both dietary physical forms, although numerically longer villi (by 15%) and deeper crypts (by 7%) were found in piglets fed dry pellets.

Age effects on morphological indices could be detected:

- Crypt depth on day 3 was decreased, and on day 7 increased numerically compared to the day at weaning;

- Crypt depth on day 7 was significantly increased compared to day 3;

- Villous length on day 3 decreased (P<0.05) compared to the day at weaning;

- On day 7 as compared to weaning, the slurry diet caused a further decrease of villous length, whereas in piglets fed the dry, pelleted diet villi were partly restored to a similar height as on the day at weaning;

- Paracellular transport increased (P<0.05) on day 3 and partially decreased on day 7 post-weaning compared to the day at weaning. The transcellular transport increased (P<0.05) on day 3 and day 7 compared to the day at weaning.

Pearson's correlates among the permeation biomarkers, morphological measures and immunological indices of the gut during 7 days post-weaning in piglets were found to be rather low (<0.5).

Contatto

Zdzislaw MROZ, (Senior researcher)
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Fax: +31-320237320
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