Two extracts derived from plant material rich in hydrolysable (Tara, T; Caesalpinia spinosa) or condensed (Mimosa, M; Acacia mearnsii) tannins were added to lamb’s diet and their effects on meat quality and on microbial population were evaluated; a diet without tannins represented the Control (C). Meat pH, vitamin E, intramuscular fat content and muscle fatty acid composition were determined. Oxidative stability and microbiological analyses were performed on meat samples after 0, 4 and 7 days of refrigerated storage. Psychrotrophic bacteria were identified through MALDI-TOF MS analysis. Regarding meat fatty acids, Tara treatment decreased the percentage of monounsaturated fatty acids. The counts of all microbial groups were similar among dietary treatments at day 0, while a significant reduction of microbial loads was observed in T-group at day 7. Pseudomonas fluorescens group count was significantly affected by T extract supplementation. The MALDI-TOF MS identification revealed the dominance of Pseudomonas fragi species in all samples while Pseudomonas lundensis, Brochothrix thermosphacta and Candida famata were revealed only in control ones. In conclusions, the tannin extract supplementation is a promising dietary strategy to preserve lamb meat quality.

Carob (Ceratonia siliqua) is commonly found in the Mediterranean region and may be used as an alternative feed resource in livestock production. However, carob contains plant secondary compounds, such as polyphenols, which limit its use due to potential toxicity problems. This study aimed to investigate whether the substitution of barley by carob pulp at a relatively high level of up to 35% causes production-level reduction and has detrimental effects on animal welfare. Lamb performance parameters such as feed intake, liveweight and carcass weight were recorded and feeding behaviour was monitored. Blood metabolites and protein profiles were determined to detect signs of metabolic distress. The inclusion of carob pulp resulted in similar level of performance by animals in all the experimental diets. However, the feeding pattern was different with feed intake being significantly lower during the first 90 min post feed supply in the carob-fed lambs compared with the Control animals, although total daily intake was similar. In terms of welfare indicators, the inclusion of carob pulp in the lambs’ diet reduced blood cholesterol while increasing both non-esterified fatty acid and urea levels. These indicate that the animals were probably under some form of metabolic stress but not at a level to cause concerns, as confirmed by the similar serum protein profile especially in terms of albumin to globulins ratio.

Sustainability of animal production requires reducing reliance on soybean meal by identifying viable alternative protein sources. Within the framework of the Italian Agritech National Research Center, seven Italian research groups collaborated to evaluate unconventional feed ingredients and their effects on animal performance and product quality. Alternative legume seeds (peas, chickpeas, faba bean, and lupins) can partially or completely replace soybean meal without impairing productivity, while enhancing product health value and shelf-life through bioactive compounds. Microalgae (Chlorella, Spirulina) improved carotenoid content, antioxidant activity, fatty acid profile, and cholesterol levels in poultry products, with limited effects in pigs. Insects supported optimal growth in fish at 25–30% inclusion, whereas maximum recommended levels are 15% in broilers and 24% in laying hens to sustain growth, egg production, and quality. Camelina by-products are suitable for poultry diets at up to 5–10%, beyond which performance declines. Whole-plant soybean silage, tef (Eragrostis tef), and triticale–lupin intercropping represent promising protein-rich resources for ruminants, provided diets maintain balanced protein-to-energy ratios, adequate fibre characteristics, and appropriate harvest timing under drought-prone conditions. Collectively, these findings highlight the potential of diverse protein sources to improve the sustainability of livestock systems while preserving productivity and enhancing the nutritional quality of animal-derived foods.

Multielemental stable isotope ratio (SIR) analysis was used in lamb plasma, erythrocytes and muscle to detect the switch from a pasture- to a concentrate-based diet, with the aim of verifying the possibility to trace the change of feeding in animal tissues. During 89 days of experimental feeding, lambs were subjected to four dietary treatments: pasture (P), pasture followed by concentrate in the stall for either 14 days (P-S14) or 37 days (P-S37) or concentrate in the stall (S). Pasture and concentrate diets comprised C3 plants only and had different values of 13C/12C, 18O/16O, 2H/1H and 34S/32S ratios. Muscle 13C/12C and 34S/32S and plasma 13C/12C and 18O/16O ratios in P, P-S14 and P-S37 lambs were significantly different. A multivariate analytical approach revealed that 13C/12C and 18O/16O ratios in plasma were the most powerful variables for the discrimination among the dietary treatments.