Systemic reuse models for sustainable glass packaging design and innovation

The Italian glass packaging industry is the first in Europe, with 21.3% of production value. It has 14 companies with 39 factories, 7,800 employees and a growing annual turnover of 2.4 billion euros. This trend of production preserves, on the one hand, a good synergy concerning the recycling process, but at the same time, it needs to reduce environmental impacts through reuse practices. This research and analysis work was carried out in collaboration with a company that designs and produces glass packaging, focusing on and evaluating the current reuse and returnable-empty models, outlining the opportunities for a transition towards systemic business that stimulates innovation in new sectors. Subsequently, through a research-through-design approach, a second concept phase defines which guidelines to design packaging within returnable vacuum systems in new sectors and which strategies are feasible to start a transition

The Italian meat production and consumption system assessed combining material flow analysis and life cycle assessment

Abstract Meat production and consumption is associated with the generation of significant environmental pressure and impacts, and resource inefficiencies. This study combines Material Flow Analysis (MFA) and Life cycle Assessment (LCA) to analyse the meat supply chain in order to better comprehend the circularity of the system, considering the Italian meat supply chain as a case study. The system boundaries of both the MFA and LCA included all the life cycle stages starting from slaughter phase to meat consumption at household and food services level. The LCA study included also all the stages upstream of the slaughter phase. Consumed meat and animal by-products (ABPs) were quantified, and the potential benefits due to the re-use of rendered ABPs were assessed. A sensitivity analysis was performed to assess the extent to which allocation choices may influence the outcomes of the analysis. The results showed an average meat consumption of 55 kg/per-capita/year with pig, poultry and cattle meat contributing respectively by 46%, 27% and 25%, followed by other meat categories, representing 2% of the total meat consumption. Daily meat consumption is responsible for the emission of 2.80 kg CO2eq per capita with beef meat contributing to 65% of the emissions. The results showed the same relative importance among meat types for acidification, terrestrial and freshwater eutrophication, and land use impact categories. The sensitivity analysis showed that allocation choices did not affect the ranking of meat categories. The system under study resulted to be efficient and to promote circularity, thanks to the re-use and valorisation of ABPs

Exploring Fourier transform mid-infra-red spectrometry to predict biochemical parameters in horse's blood

The aim of this study was to evaluate the use of Fourier transform mid-infra-red (FT-MIR) spectrometry to analyse blood biochemical parameters of the horse. For this purpose, mid infrared transmission spectra were acquired from plasma samples from 72 healthy horses. Each sample was also analysed using reference clinical chemical methods, and these results were used as calibrating values to develop predictive models by partial least squares method. The validation was carried out using external validation method. The coefficient of determination (R2) and the ratio of prediction to deviation (RPD) showed high values for parameters regarding energy and protein metabolism. Among energy parameters, an excellent prediction model was developed for total cholesterol (R2 = 0.94; RPD = 4.40) and triglycerides (R2 = 0.96; RPD = 5.0) while fair results were obtained for cholesterol fractions (R2 range: 0.75–0.80; RPD range: 2.0–2.3). Among protein metabolism parameters, excellent prediction models were developed for total protein, albumin, globulin (R2 range: 0.96–0.99; RPD range: 5.40–9.30) and good prediction model for urea (R2 = 0.90; RPD = 3.2), confirming previous results with the plasma of dairy cows. Our results highlight that FT-MIR spectrometry offers an accurate measurement of important plasma biomarkers for the evaluation of energy (cholesterol and triglycerides) and protein metabolism (urea), as well as for health status (albumin/globulin ratio). Our results may open an interesting perspective of a more cost-effective approach to monitoring the metabolic status and health conditions of the horse, with the future possibility to predict some blood biomarkers by the practitioner in field.Highlights FT-MIR potential to measure blood parameters in horses was explored; Infra-red spectrometry can be used in horse's clinical chemistry; Fast and cost-effective metabolic status evaluation in horses; Accurate FT-MIR predictions for plasma protein and lipid fractions in horses

Effects of different plant extracts at various dietary levels on growth performance, carcass traits, blood serum parameters, immune response and ileal microflora of Ross broiler chickens

A study was conducted to evaluate the effects of different plant extracts (common nettle, coriander, dill and thyme) at various dietary levels (0, 150, 300 and 450 mg/L) on growth performance, carcass traits, blood serum parameters, immune response and ileal microflora of 650 male Ross chickens (13 treatment groups; five replicates/treatment group; 10 birds/replicate) in a 42-day trial. Plant extracts were added to drinking water. Supplementation, except for coriander, increased feed intake (p < .05). Thyme extracts at 300 mg/L improved both weight gain and feed efficiency (p < .05). Thyme or dill (300 mg/L) improved carcass and drumsticks yields (p < .05). Pre-slaughtered body weight was increased by supplementation with plant extracts at 300 mg/L (p < .05). Plant extracts positively affected blood serum parameters decreasing concentrations (p < .05) of total protein, albumin, urea and total cholesterol. Dill extract increased IgG against sheep red blood cells at d 28 (p < .05) and d 42 (IgG; tendency p= .0698), whereas coriander extract (450 mg/L) raised immune response against avian influence within 42 d from vaccination (p < .05). Plant extracts reduced coliforms (except dill at 300 mg/L level; p < .05) and aerobic bacteria (except dill; p < .05). Negative gram bacteria were increased by thyme and dill treatments at 150 mg/L (p < .05) whereas lactobacilli bacteria were raised by thyme at 150 mg/L level (p < .05). In conclusion, supplementation with thyme at 300 mg/L level had the greatest benefits on the evaluated parameters.HIGHLIGHTS Thyme supplementation at 300 mg/L level could improve broiler chicken growth performance, carcass traits and blood serum parameters. Thyme supplementation at 150 mg/L could positively affect ileal microbiota increasing lactobacilli bacteria and reducing coliforms. However, no relevant effects of the thyme treatment were observed on broiler chicken immune responses

A propensity score-weighted comparison between adalimumab originator and its biosimilars, ABP501 and SB5, in inflammatory bowel disease: a multicenter Italian study

Background: Adalimumab is an effective and safe biological drug for the treatment of inflammatory bowel disease (IBD). Nowadays, several biosimilar agents are available, but data regarding their efficacy and safety in patients with IBD are still lacking. We aimed to compare the effectiveness and tolerability between adalimumab originator, ABP501 and SB5 biosimilars in patients with IBD in the short term (after induction and after 6 months of treatment) through a propensity score-weighted multicenter cohort study. Methods: We included 156 patients with IBD, 69 patients with ulcerative colitis and 87 patients with Crohn's disease (CD) receiving ABP501 or SB5 biosimilars from January 2019 to April 2020 for moderate-to-severe disease. For comparison, a group of age- and sex-matched patients treated with adalimumab originator was used. We collected clinical and biochemical data after induction and at 6 months of treatment. Endoscopic data were recorded only at baseline. Results: Overall, clinical benefit was achieved by 86.4% and 85.3% after induction and at 6 months, respectively, without a statistically significant difference between the three treatment groups (p = 0.68 and p = 0.46). However, after induction, we found significant differences between the two types of the disease (ulcerative colitis or CD, p = 0.004), with a greater clinical benefit achieved by patients with CD. Also, the therapeutic optimization rate between the three drugs was not statistically significant different (p = 0.30). All treatments showed a good safety profile, with only 10 patients who needed to stop therapy because of adverse events. Conclusion: Adalimumab biosimilars seem to be as effective and safe as the originator in patients with IBD. Surely, they represent a great opportunity to reduce the costs of biological therapies, however larger and longer real-life studies are necessary

Residual feed intake is related with metabolic and inflammatory response during the pre-weaning period in Italian Simmental calves

Residual Feed Intake (RFI) is defined as the difference between measured and predicted intake. Understanding its biological regulators could benefit farm profit margins. The most-efficient animals (M-Eff) have observed intake smaller than predicted resulting in negative RFI, whereas the least-efficient (L-Eff) animals have positive RFI. Hence, this observational study aimed at retrospectively comparing the blood immunometabolic profile in calves with divergent RFI during the preweaning period. Twenty-two Italian Simmental calves were monitored from birth through 60 d of age. Calves received 3 L of colostrum from their respective dams. From 2 to 53 d of age, calves were fed a milk replacer twice daily, whereas from 54 to 60 d (i.e., weaning) calves were stepped down to only one meal in the morning. Calves had ad libitum access to concentrate and intakes were recorded daily. The measurement of BW and blood samples were performed at 0, 1, 7, 14, 21, 28, 35, 45, 54, and 60 d of age. Calves were ranked and categorized as M-Eff or L-Eff according to the median RFI value. Median RFI was –0.06 and 0.04 kg of DMI/d for M-Eff and L-Eff, respectively. No evidence for group differences was noted for colostrum and plasma IgG concentrations. Although growth rate was not different, as expected, [0.67 kg/d (95% CI = 0.57 ‒ 0.76) for both L-Eff and M-Eff) throughout the entire pre-weaning period (0–60 d), starter intake was greater in L-Eff compared with M-Eff calves (+36%). Overall, M-Eff calves had a greater gain-to-feed ratio compared with L-Eff calves (+16%). Plasma ceruloplasmin, myeloperoxidase, and reactive oxygen metabolite concentrations were greater in L-Eff compared with M Eff calves. Compared with L-Eff, M-Eff calves had an overall greater plasma concentration of globulin, and γ-glutamyl transferase (indicating a better colostrum uptake) and Zn at 1 d. Retinol and urea were overall greater in L-Eff. The improved efficiency in nutrient utilization observed in M-Eff was paired with a lower grade of oxidative stress and systemic inflammation. L-Eff may have had greater energy expenditure to sup port the activation of the immune system. Keywords: Residual feed intake, Growth performance, Metabolic profile, Simmental calves.peer-reviewe

Environmental impact assessment at different scale levels of the livestock sector

Negli ultimi tre decenni la domanda globale di cibo, in particolare di proteine animali (carne, latte, uova), è aumentata in base alla crescita della popolazione che dovrebbe arrivare a 9 miliardi di persone entro il 2050. Questi alimenti rappresentano infatti un'importante fonte di energia, proteine di alta qualità, micronutrienti e vitamine. Pertanto, questo miglioramento potrebbe contribuire all'aumento della durata della vita e della domanda di cibo. Ciò ha costretto il settore agricolo ad un'ulteriore intensificazione che ha interessato anche la coltivazione di colture per l'alimentazione animale. Le produzioni agricole e zootecniche hanno un impatto ambientale rilevante, e questo argomento è oggetto di critiche e di indagini scientifiche anche per definire più accuratamente il loro contributo e le relative potenziali strategie di mitigazione, considerando anche che la fase agricola è il principale contributore dell'impatto ambientale della catena di produzione alimentare. Si riconosce infatti che il settore agricolo contribuisce direttamente al 21% delle emissioni totali di gas serra di origine antropica a livello mondiale e consiste per lo più di metano seguito da protossido di azoto e anidride carbonica. Queste emissioni sono per lo più associate alla produzione zootecnica, in particolare all'allevamento di ruminanti che contribuisce con le emissioni dirette di metano dovute alla fermentazione dei ruminanti e alla fermentazione del letame; la restante parte è composta da emissioni indirette dovute alla deforestazione, all'uso di energia e alla produzione di mangimi. Lo scopo di questa tesi è stato la valutazione dell'impronta ambientale nel settore zootecnico a diversi livelli di scala tematica. La filiera italiana della carne, gli allevamenti lattiero-caseari, un caseificio per la produzione di Grana Padano DOP e i singoli animali sono stati studiati per quantificare l'impronta ambientale. Nel primo lavoro è stata valutata la filiera italiana della carne con un approccio di analisi dei flussi di massa e di valutazione del ciclo di vita. In primo luogo, la quantificazione della carne è stata effettuata dalla macellazione al consumo domestico, partendo dal peso della carcassa fino alla carne realmente consumata. A questo livello si è tenuto conto della carne di bovini, suini, ovini e caprini, equidi e conigli. Durante la catena sono state quantificate anche le perdite di carne e i rifiuti. In particolare, i sottoprodotti di origine animale (SOA) sono stati quantificati per singole specie e classificati in base al rischio a livello sanitario secondo il regolamento (CE) 1069/2009. Secondo la categoria (Cat 1, Cat 2 o Cat 3), supponendo che tutti i SOA fossero destinati al processo di rendering, l'uso e lo smaltimento dei prodotti dopo rendering è stato identificato. L'analisi dei flussi di massa ha confermato come l'Italia sia un importatore netto di carne bovina e suina, mentre è autosufficiente per quanto la carne avicola. L'analisi dei flussi di massa rivela che nel 2013 sono stati consumati in Italia 2,86 Mt di carne. Questo valore equivale a 131 g/giorno/pro-capite e a 47,91 kg/anno/pro-capite di carne consumata. In percentuale la quantità totale di carne consumata è rappresentata dal 46% da carne suina, dal 28% di carne avicola, dal 23% di carne bovina e dal 3% di altre carni (coniglio, equini, ovini e caprini). Questo approccio ha permesso di quantificare anche sottoprodotti di origine animale (SOA) prodotti durante la fase di macellazione e gli scarti alimentari a livello di vendita al dettaglio e fase di consumo. La fase di macellazione è risultata essere la principale fonte di rifiuti, producendo il 48% di rifiuti originati nella filiera della carne. I risultati hanno evidenziato come i SOA siano già quasi completamente riutilizzati, compatibilmente con il loro rischio a livello sanitario, dimostrando la circolarità del sistema e permettendo di quantificare anche i prodotti evitati grazie al loro riutilizzo e le relative emissioni di gas serra evitate. Per quanto riguarda gli altri rifiuti alimentari, i risultati della presente valutazione possono essere considerati solo una stima per la mancanza di specifici coefficienti nazionali. Dopo la fase di quantificazione, è stato applicato l'approccio del Life Cycle Assessment (LCA) per valutare l'impronta ambientale, considerando anche il prodotto evitato grazie al riutilizzo dei sottoprodotti del rendering. I risultati dell'LCA rivelano che il consumo giornaliero di carne pro-capite emette 4,0 kg di CO2eq, con un contributo della care bovina pari al 30%, della carne suina pari al 9.6% e della carne avicola pari all’8%. Le emissioni relative ai SOA sono risultate essere pari al 60% di quelle totali e il loro riutilizzo ha permesso una riduzione di queste del 10%. Il secondo ed il terzo lavoro sono stati invece relativi al potenziale di riscaldamento globale (GWP) di latte bovino e Grana Padano DOP. Complessivamente sono stati valutate ventisette aziende zootecniche con bovine da latte, con latte destinato al formaggio Grana Padano DOP, e un caseificio, situato nella provincia di Piacenza. I dati primari sono stati raccolti utilizzando un questionario appositamente redatto. Questo ha incluso per le aziende agricole la richiesta di dati relativi alla composizione della mandria, la gestione dell'alimentazione, la produzione di latte e performance riproduttive, piani colturali e l'utilizzo delle risorse energetiche e dei materiali di lettime, mentre per il caseificio sono stati richiesti dati relativi all'utilizzo delle risorse energetiche e gli input richiesti dal processo di caseificazione. Nel secondo lavoro sono state valutate 10 aziende lattiere per valutare l'impronta di carbonio del latte (CF) e individuare le principali fonti di emissioni. Lo studio ha utilizzato un approccio dalla culla alla tomba considerando come unità funzionale un 1 kg di latte corretto per contenuto di grasso e proteine (FPCM). Il valore medio di CF di 1 kg di FPCM è risultato essere pari a 1,33 kg di CO2eq/kg FPCM con però un ampio range di variazione, da 1,02 a 1,62 kg di CO2eq/kg FPCM. Le emissioni dovute alle fermentazioni enteriche e alle fermentazioni da reflui rappresentano il 52% del totale, mentre le emissioni relative agli alimenti acquistati il 36%. L'autoproduzione e il consumo energetico rappresentano invece rispettivamente il 6% e il 6%. Nel terzo lavoro invece è stata presa in considerazione la produzione di Grana Padano DOP. In questo caso è stato utilizzato un approccio dalla culla al cancello del caseificio considerando come unità funzionali 1 kg di FPCM e 1 kg di Grana Padano DOP stagionato 9 mesi. Il latte destinato alla produzione del formaggio ha mostrato un valore medio di CF pari a 1,38 kg CO2eq/kg FPCM, con un valore minimo di 1,02 e uno massimo di 1,94 kg CO2eq/kg FPCM. Il valore medio di CF di 1 kg di formaggio Grana Padano DOP è stato invece pari a 9,99 kg di CO2eq, con un contributo della fase agricola pari al 94%. I risultati di questi lavori si sono mostrati in accordo con studi simili riportati in bibliografia e hanno inoltre permesso di evidenziare come gli allevamenti da latte mostrassero un maggior livello di sostenibilità ambientale ma con possibilità di miglioramento principalmente attraverso il miglioramento della gestione delle mandrie (prestazioni produttive e riproduttive). Il quarto lavoro ha riguardato invece lo sviluppo di proxy in grado di prevedere le emissioni di metano da singole bovine da latte. Questo focus è un punto caldo di ricerca, soprattutto perché di fondamentale importanza per individuare strategie di mitigazione efficaci per la riduzione delle emissioni di metano dovute a fermentazioni ruminali, gas ad effetto serra riconosciuto avere il maggior contributo sul totale delle emissioni. Le emissioni di metano dipendono principalmente dal quantitativo di concentrato assunto e dalla composizione generale della dieta, ma tuttavia nelle aziende agricole commerciali risulta difficile quantificare con precisione l’ingestione di alimenti. Lo studio ha quindi mirato a verificare la possibilità di utilizzare la tecnologia del vicino infrarosso (NIRS) utilizzando lo spettro di campioni di feci (NIRSf) e/o in combinazione con altri parametri fenotipici disponibili a livello aziendale per prevedere la produzione di metano (MP, g/giorno) dalle singole vacche da latte in lattazione. Il NIRSf da solo ha permesso una stima abbastanza buona della produzione di metano e le stime sono state migliorate in misura simile quando sono stati considerati il peso vivo o la produzione di latte tal quale o la produzione di latte corretta per il contenuto energetico, mentre la combinazione del NIRSf con più di un altro parametro ha migliorato le stime solo in misura molto limitata. Il metano può essere previsto utilizzando modelli che considerano l’ingestione di sostanza sezza, il peso vivo o la produzione di latte ma il limite principale è rappresentato dalla disponibilità dei dati a livello aziendale. La tecnica del vicino infrarosso applicata ai campioni fecali, in particolare se combinata con altri parametri fenotipici, può rappresentare una valida alternativa per misurazioni su larga scala in allevamenti da latte commerciali, quando l’ingestione di sostanza secca di solito non è disponibile, per la selezione genetica di vacche da latte a bassa emissione.In the last three decades global demand of food, in particular animal proteins (meat, milk, and eggs), has increased according to the population growth, that is expected to go up to 9 billion by the 2050. These, in fact, represent an important source of energy, high-quality protein, micronutrients and vitamins. Therefore, this improvement could contribute to the lifespan increase and food demand. The latter forced the agricultural sector to a further intensification that affected also the cultivation of crops for animal feeding. Agricultural and livestock productions have a relevant environmental impact, and this topic is object of criticism and scientific investigation also to more accurately define its contribution and potential mitigation strategies, considering also that agricultural stage is the main contributor to the environmental impact of the food production chain. It is recognized, in fact, that agricultural sector directly contribute to the 21% of total global anthropogenic greenhouse gas emissions, mostly consisting of methane followed by nitrous oxide and carbon dioxide. These emissions are mainly associated with the livestock production, in particular with ruminants breeding that contributes directly to methane emissions due to ruminal and manure fermentation; the remaining part is composed by indirect emissions from deforestation, energy use and animal feed production. The scope of this thesis was the evaluation of environmental footprint in the livestock sector at different subject scale level. Italian meat supply chain, dairy farms, Grana Padano PDO cheese factory and single animals was investigated in order to quantify environmental footprint. In the first work, the Italian meat supply chain has been evaluated whit a mass flow analysis (MFA) approach and life cycle assessment (LCA) approach. Firstly, the quantification of meat had been made from slaughter to household consumption, starting form carcass weight to real meat consumed. At these levels, meat form cattle, pig, sheep and goat, equidae, and rabbit was taken in account. During the chain also meat losses and waste were quantified. In particular animal by-products (ABPs) were quantified for single species and categorized into heath level risk according to the Regulation (EC) 1069/2009. According to the category (Cat 1, Cat 2 or Cat3), assuming that all ABPs were destinated to rendering process, use and disposal of rendered products was identified. The MFA confirmed how Italy is a net importer of cattle and pork meat while it is self-sustaining for poultry meat. Mass flow analysis revealed that in 2013, 2.86 Mt of meat were consumed in Italy. It is equivalent to 131 g/day/pro-capita and to 47.91 kg/year/pro-capita of meat consumed. In percentage the total amount of consumed meat is represented by 46% of pig, 28% of poultry and 23% of cattle and 3% of other meat (rabbit, equidae, and sheep and goat). This approach quantified the ABPs produced at slaughtering level and food wastes at retail and consumer levels. Slaughter phase was the main source of waste, producing 0.80 Mt of ABPs, 48% of the total amount of waste originated in the meat supply chain. Results highlighted how the ABPs are already almost completely reused, compatibly with their health level risk, demonstrating the circularity of the system through the quantification of the avoided products and relative GHGs emissions. Concerning other food wastes, the results of the present evaluation could be considered only an estimate due to the lack of specific national coefficients. After quantification LCA was applied in order to evaluate environmental footprint, considering also avoided product due to the re-use of rendered ABPs. LCA results reveal that daily meat consumption pro-capita emits 4.0 kg CO2eq represented by 30% of cattle meat, 9.6% of pig meat and 8% of poultry meat. Emissions allocated to ABPs are the 60% and their re-use decrease the emissions about 10%. Second and third works focused the milk and PDO Grana Padano global warming potential (GWP). Overall, twenty-seven dairy farms, producing milk destinated to Grana Padano PDO cheese and one cheese factory, situated in the Piacenza province were evaluated. Primary data were collected by using a specific survey. This included for the farms the request of data regarding herd composition, feeding management, milk production, herd management and performace, crops cultivation and resource use, whereas for the cheese factory, the survey included energy resource use and input requested by cheese making process. In the second work, 10 dairy farms were evaluated in order to assess the milk Carbon Footprint (CF) and the main source of emissions. The system boundary was a cradle-to-farm-gate and functional unit is 1 kg of FPCM (Fat and Protein corrected milk). The CF of 1 kg of FPCM resulted equal to 1.33 kg CO2eq/kg FPCM with a wide range of variation from 1.02 to 1.62 kg CO2eq/kg FPCM. Emissions due to enteric fermentation and manure fermentation represented the 52% of the total, while acquired feed the 36%. Self-production and energetic consumption represented 6% and 6% respectively. In the third, Grana Padano PDO production was considered. The milk destinated to cheese processing showed an average value of CF equal to 1.38 kg CO2eq/kg FPCM, with a minimum value of 1.02 and a maximum one of 1.94 kg CO2eq/kg FPCM. Instead, the CF average value of 1 kg of PDO Grana Padano cheese was equal to 9.99 kg CO2eq, showing an agricultural stage contribution of 94%. Results of these works were in accord with similar studies reported in literature and had pointed out how dairy farms showed a greater level of environmental sustainability but with possibilities for improvement, mainly through herd management enhancement (productive and reproductive performances). Fourth work was about the development of proxies able to predict the methane emissions from individual cows. This focus is a hot research point in order to improve the mitigation strategies to reduce methane emissions because of the main GHG contributor. Methane emission is mainly driven by feed intake and diet composition, but it is difficult to measure intake in commercial farms. The study aimed to verify the possibility of using NIRS of faeces (NIRSf) alone and in combination with other phenotypic parameters available at a farm level to predict methane production (MP, g/d) from individual lactating dairy cows. NIRSf alone allowed a fairly good estimation of methane yield and the estimations were improved to a similar degree when BW, MY or ECM were considered, whereas combining NIRSf with more than one other parameters improved the estimations with a very little extent only. Methane can be predicted using models that consider the DMI, BW or MY but the main limitation is represented by the data availability. Near Infrared technique applied to faecal samples, in particular when combined with other phenotypic parameters, can represent a valid alternative for large-scale measurements in commercial dairy farms for genetic selection of low emitters dairy cows, when DMI measurement is usually not available

Dietary Supplementation of Inorganic, Organic, and Fatty Acids in Pig: A Review

Reduction of antibiotic use has been a hot topic of research over the past decades. The European ban on growth-promoter use has increased the use of feed additivities that can enhance animal growth performance and health status, particularly during critical and stressful phases of life. Pig farming is characterized by several stressful periods, such as the weaning phase, and studies have suggested that the proper use of feed additives during stress could prevent disease and enhance performance through modulation of the gastrointestinal tract mucosa and microbiome. The types of feed additive include acids, minerals, prebiotics, probiotics, yeast, nucleotides, and phytoproducts. This review focuses on commonly used acids, classified as inorganic, organic, and fatty acids, and their beneficial and potential effects, which are widely reported in the bibliography. Acids have long been used as feed acidifiers and preservatives, and were more recently introduced into feed formulated for young pigs with the goal of stabilizing the stomach pH to offset their reduced digestive capacity. In addition, some organic acids represent intermediary products of the tricarboxylic acid cycle (TCA), and thus could be considered an energy source. Moreover, antimicrobial properties have been exploited to modulate microbiota populations and reduce pathogenic bacteria. Given these potential benefits, organic acids are no longer seen as simple acidifiers, but rather as growth promoters and potential antibiotic substitutes owing to their beneficial action on the gastrointestinal tract (GIT)