The aim of this work was to improve the fatty acid profile of meat from light lamb, frequently reared in Spain and in other Mediterranean countries. A total of 44 light lambs fed different n-3 polyunsaturated fatty acids sources were studied: control (C) (palm oil), extruded linseed (L), extruded linseed mixed with microalgae (LM) and fish oil (FO). The productive performance from 14.7 to 26.2 kg of live weights and meat quality characteristics during refrigerated storage were assessed. Lambs fed FO showed lower feed intake (p <0.001), average daily gain (p <0.001) and higher feed conversion ratio (p <0.001) than lambs from the other treatments. Fish oil meat had the lowest (p <0.01) protein proportion and the highest (p <0.001) C20:5n-3, C22:5n-3 and C22:6n-3 proportions, while L or LM produced the highest (p <0.001) C18:3n-3 deposition. Fish oil meat had higher (p <0.05) L* and lower (p <0.001) a* than meats from the other treatments. After 7 days of storage, FO meat showed the highest TBARS (p <0.001), while C meat showed similar value to 0 days of storage. Additionally, FO underwent higher microbial growth after 7 days of storage as compared to the other treatments. Dietary supplementation with L and LM leads to C18:3n-3 meat enrichment and to a microbial load and colour characteristics similar to those of C, without adverse effect on lamb performance. However the use of FO improves the fatty acid profile of meat, but negatively affects lamb performance and meat quality.

Contents: The objective of this investigation was to establish the optimal extent of dilution for storage of boar spermatozoa at 15°C in Kiev diluent. The dilution titers used for the sperm‐rich fraction of ejaculates from 8 boars ranged from 1:2 to 1:50. Seminal doses were stored for 10 days. Motility and acrosome morphology were evaluated after 1, 3, 5, 7, and 10 days of storage. The percentages of motile spermatozoa after 24 and 72 hours of storage were significantly higher for dilution rates between 1:7 and 1:11 than for dilution rates lower than 1:7 or higher than 1:11 (p < 0.05). The percentages of spermatozoa with normal acrosomes after 24, 72, and 120 hours of storage were significantly higher for dilution rates between 1:8 and 1:11 than for dilution rates lower than 1:8 or higher than 1:11 (p < 0.01).

Many factors related to transport to abattoir affects meat quality, but scarce information is available in suckling lambs. Thus, the aim of this work was to evaluate the effects of season and stocking density on carcass and meat quality of suckling lambs during commercial transport to the abattoir. A factorial design (2 × 3) was used: two seasons (winter and summer) and three stocking densities (SD; 0.08, 0.12 and 0.20 m2 animal-1). Meat quality variables were measured in the M. longissimus at 24 h post-mortem and after 5 days of refrigerated storage. Lambs transported in summer showed lower liver weight (p<0.001), h* (p<0.05), deoxymyoglobin content (p<0.001), pressed juice (p<0.01), shear force (p<0.001) and firmness (p<0.001), and higher initial pH (p<0.001), L*, b*, C* (p<0.001) and a* (p<0.01), as well as metmyoglobin and oxymyoglobin content (p<0.001), than those transported in winter. The effect of season was dependent on storage time, being colour changes more evident at 24 h than after 5 days of storage, whereas lipid oxidation was only observed in stored meat, which may be explain because the natural antioxidative system decreases with time after slaughter. Scarce effect of SD was found on the carcass and meat quality parameters, thus under our experimental conditions the three SD studied appear to be suitable for suckling lambs transport. However, both carcass and meat quality were within the normal commercial range.

Revisamos la relación entre el enriquecimiento ambiental y el bienestar de los peces, incluido el enriquecimiento ocupacional. Explicamos los diferentes aspectos a tener en cuenta y concluimos que el enriquecimiento ocupacional no parece tener efectos negativos sobre el crecimiento y que puede ayudar a sobrellevar los efectos de un estresor agudo.

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