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Chia (Salvia hispanica L.) seed (SHS) dietary supplementation is effective in improving the nutritional quality of rabbit meat for consumers and could contribute to the novel concept of “functional food” in human nutrition. A trial has been conducted in order to verify the effects of three levels (0, 10, or 15%) of SHS inclusion in a rabbit diet on the meat quality, oxidative stability and sensory traits. The dietary treatment did not induce any differences in the ultimate pH, chemical composition, drip losses of the longissimus dorsi muscle or the initial and ultimate pH of the biceps femoris muscle, but the SHS supplementation increased cooking losses of the rabbit meat. The inclusion of SHS also reduced oxidative stability during meat storage. No adverse effects were observed on the meat quality or customer acceptability. The inclusion of SHS in rabbit diets, which is effective in improving the n-3 polyunsaturated fatty acids content of meat, increased the lipid oxidation in the hind leg meat. An improvement in tissue oxidative stability could be obtained by feeding rabbits with higher levels of antioxidants

Aim of the study was to evaluate the effect of different proportions of hay and fresh grass in goats’ diet on milk fatty acid profile. Nine Camosciata goats were fed a fixed amount of concentrate (30% of total diet) and different percentages (40% vs 30%, 50% vs 20% and 60% vs 10%) of hay and fresh grass, respectively. Diminishing amounts of fresh grass percentages in the diet led to significant increases of lauric, myristic and palmitic acids (P ≤ 0.001) and to significant decreases of C18:1 t6‐11, rumenic and α‐linolenic acids (P ≤ 0.001) in milk, thus determining a worsening of the health value of milk fat.

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14Goal of this study was to evaluate the kinetics of goat milk fatty acids during abrupt 15 transition from indoor to pasture-based diets. Twelve Valdostana goats in mid-lactation 16 reared indoors and fed hay and concentrates for 40 days were abruptly brought outdoors 17 on natural pasture and fed fresh grass ad libitum. Feed samples and individual milk 18 samples were collected for fatty acids analysis on the last day of indoor feeding (day 0) 19 and after 1, 2, 3, 4, 6, 9, 13, 18 and 23 days of fresh grass feeding. Milk fatty acid 20 composition was significantly affected by sampling day. Significant changes already took 21 place few days after transition. The most marked and consistent variations occurred at the 22 expense of some unsaturated fatty acids. Total trans-octadecenoic and trans-23 octadecadienoic acids, conjugated linoleic acids (CLA) and omega-3 fatty acids constantly 24 increased, reaching concentrations 4.0, 3.0, 3.9, and 2.2 times higher at the end of the trial 25 than at its beginning, respectively. On the last sampling day the omega-6/omega-3 fatty 26 *Manuscript 2 acids ratio was two times lower than its initial value. Considering individual fatty acids, 27 the most consistent and remarkable increasing trends throughout the trial were observed 28 for C18:1 t6-11, C18:1 t12-14+c6-8, C18:1 c14+t16, C18:2 t11c15, C18:2 c9t13+t8c12, 29 CLA isomers c9t11+t7c9+t8c10 and t11c13+c9c11. Alpha-linolenic and eicosapentaenoic 30 acids also increased significantly, but to a lesser extent. In view of the many beneficial 31 biological effects that have been attributed to vaccenic acid (C18:1 t11), rumenic acid 32 (C18:2 c9t11), and omega-3 fatty acids, results showed that, from a human health 33 perspective, goat milk fatty acid composition consistently improved after transition from 34 indoor to pasture feeding. Such improvements, mainly due to the high content of -35 linolenic acid in pasture plants, were already significant after two or three days of fresh 36 grass feeding. Further increases of beneficial fatty acids in milk fat were observed till 37 about thirteen (vaccenic acid and CLA) or twenty-three (omega-3 fatty acids) days after 38 transition. These results show that pasture can be considered a natural feeding strategy to 39 quickly enhance the healthfulness of goat milk fat. The positive effects of fresh grass-based diets on the fatty acid (FA) profile and the 45 nutritional quality of dairy fat have been recognized broadly (Morand-Fehr et al., 2007). 46 Such improvement is related to both increased milk concentrations of polyunsaturated FA 47 (e.g., omega-3 FA and conjugated linoleic acid) which are known to exert many putative 48 beneficial effects for human health (Barcelo-Coblijn and Murphy, 2009; Benjamin and 49 Spener, 2009) and decreased concentrations of saturated FA (particularly lauric, myristic, 50 and palmitic acids) able to raise risk factors for cardiovascular diseases (Ohlsson, 2010). 51Modifications and persistency of ruminant milk FA concentrations determined by ...