The review discusses the topics presented below, with experimental data and more evidence for some aspects which are problematic for the pig producer. To obtain high quality processed pig products, heavy pig production in Italy is subjected to rules fixed by several Consortia, on the basis of the experience of producers and the results from scientific research. Slaughter animals of at least 9 months of age and 160 kg live weight are required to provide heavy cuts with excellent meat. Breeds are limited to Italian Large White and Landrace, selected for specific parameters such as loss at 1st salting of the ham, and their crosses. Crosses with Duroc and hybrids can be used if obtained from selection and crossing schemes that fit the objectives of Italian selection. Backfat thickness must be “sufficient” to obtain retailed fresh hams with fat cover ranging from 20 to 30 mm, depending on ham weight, and the content of linoleic acid in ham fat cover cannot exceed 15%. Fat quantity and quality in feeds ... RiassuntoLa rassegna discute gli aspetti di seguito riportati, argomentandoli con dati sperimentali ed evidenziandone gli elementi più problematici per i produttori. Per ottenere prodotti trasformati di suino d’alta qualità, la produzione italiana del suino pesante é sottoposta a regole fissate dai Consorzi, sulla base dell’esperienza dei produttori e dei risultati della ricerca scientifica. Sono richiesti soggetti da macello di almeno 9 mesi di età e 160 kg di peso vivo, per fornire tagli pesanti con carni eccellenti. Sono permessi solo soggetti di razza Large White Italiana e Landrace, Italiana, selezionati per parametri specifici, quale il calo di prima salatura del prosciutto, oppure provenienti dal loro incrocio. I prodotti d’incrocio con il Duroc e gli ibridi commerciali possono essere usati se ottenuti con schemi di selezione ed incrocio che rientrino negli obiettivi della selezione italiana. Lo spessore del lardo deve essere “sufficiente” per ottenere prosciutti rifilati con una copertura adiposa ...

The enterotoxigenic Escherichia coli (ETEC) expressing F4 and F18 fimbriae are the two main pathogens associated with post-weaning diarrhea (PWD) in piglets. The growing global concern regarding antimicrobial resistance (AMR) has encouraged research into the development of nutritional and feeding strategies as well as vaccination protocols in order to counteract the PWD due to ETEC. A valid approach to researching effective strategies is to implement piglet in vivo challenge models with ETEC infection. Thus, the proper application and standardization of ETEC F4 and F18 challenge models represent an urgent priority. The current review provides an overview regarding the current piglet ETEC F4 and F18 challenge models; it highlights the key points for setting the challenge protocols and the most important indicators which should be included in research studies to verify the effectiveness of the ETEC challenge. Based on the current review, it is recommended that the setting of the model correctly assesses the choice and preconditioning of pigs, and the timing and dosage of the ETEC inoculation. Furthermore, the evaluation of the ETEC challenge response should include both clinical parameters (such as the occurrence of diarrhea, rectal temperature and bacterial fecal shedding) and biomarkers for the specific expression of ETEC F4/F18 (such as antibody production, specific F4/F18 immunoglobulins (Igs), ETEC F4/F18 fecal enumeration and analysis of the F4/F18 receptors expression in the intestinal brush borders). On the basis of the review, the piglets’ response upon F4 or F18 inoculation differed in terms of the timing and intensity of the diarrhea development, on ETEC fecal shedding and in the piglets’ immunological antibody response. This information was considered to be relevant to correctly define the experimental protocol, the data recording and the sample collections. Appropriate challenge settings and evaluation of the response parameters will allow future research studies to comply with the replacement, reduction and refinement (3R) approach, and to be able to evaluate the efficiency of a given feeding, nutritional or vaccination intervention in order to combat ETEC infection.

Out of the alternatives to antibiotics and zinc oxide, organic acids, or simply acidifiers, play significant roles, especially in ensuring gut health and the growth performance of pigs. Regarding acidifiers, formic acid and its salts have shown very promising results in weaning, growing and finishing pigs. Although it is known that the main mechanisms by which acidifiers can improve livestock performance and health are related to the regulation of gastrointestinal pH, an improvement in intestinal digestibility and mineral utilization, and their antimicrobial properties against specific pathogens has been observed, while poor consensus remains in relation to the effect of acidifers on bacteria and the complex microbiome. Therefore, the aim of the present review was to critically evaluate the effects of formic acid and its salts on the performance and the gastrointestinal microbiota balance of pigs.

We tested the effect of Trp addition to a standard weaning diet and oral challenge with enterotoxigenic Escherichia coli K88 (ETEC) on growth and health of piglets susceptible or nonsusceptible to the intestinal adhesion of ETEC. Sixty-four pigs weaned at 21 d of age were divided into 3 groups based on their ancestry and BW: a control group of 8 pigs fed a basal diet (B), the first challenged group of 28 pigs fed B diet (BCh), and the second challenged group of 28 pigs fed a diet with Trp (TrpCh). The Trp diet was produced by the addition of 1 g of l-Trp/kg to the basal diet. On d 5, pigs were orally challenged with 1.5 mL suspension containing 10¹⁰ cfu ETEC/mL or placebo, and killed on d 9 or 23. Based on in vitro villus adhesion assay, the pigs (except the B group) were classified as susceptible (s⁺) or nonsusceptible (s⁻) to the intestinal ETEC adhesion. Thus, after the challenge, treatments were B, BChs⁻, BChs⁺, TrpChs⁻, and TrpChs⁺. Pigs susceptible to ETEC were 50.0% in the BChs⁺ group (3 pigs lost included) and 46.4% in the TrpChs ⁺ group (1 pig lost included). During the first 4 d after challenge, the challenge reduced ADG (P < 0.05), and this reduction was greater in susceptible pigs (P < 0.05) than nonsusceptible ones. Tryptophan increased ADG and feed intake in susceptible pigs (P < 0.05) from challenge to d 4, but not thereafter. Tryptophan supplementation did not improve the fecal consistency and did not reduce the number of pigs positive for ETEC in feces on d 4 after the challenge. The K88-specific immunoglobulin A activity in blood serum tended to be greater in challenged pigs (P = 0.102) and was not affected by the addition of Trp. Villous height was affected by the addition of Trp and challenge in different ways, depending on the site of small intestine. The need to consider the phenotype for the adhesion of the ETEC in studies with different supply of Trp was clearly evident. When compared with practical weaning standard diets, Trp supplementation allowed susceptible pigs to partially compensate for the effects of ETEC challenge by increasing feed intake and maintaining an adequate BW growth. This is of practical importance for the formulation of diets for pigs selected for lean growth because of the presence of an association between this trait and the susceptibility to the intestinal adhesion of ETEC. Copyright © 2009. . Copyright 2009 Journal of Animal Science