Fatty acid profile in the ruminal fluid and in the m. longissimus dorsi of lambs fed herbage or concentrate with or without tannins

Twenty-eight male lambs were divided into two groups at age 45 d. Fourteen lambs were given fresh herbage (vetch); the remaining lambs were fed a concentrate-based diet. Within each treatment, seven lambs received a supplementation of quebracho tannins. At slaughter (age 105 d) the ruminal content and the muscle longissimus dorsi (LD) were collected. Ruminal fluid and LD fatty acid composition was determined by gas chromatography. Among the concentrates-fed lambs, tannins supplementation reduced (P < 0.05) the concentration of C18:0 (- 49 %) and increased vaccenic acid (VA; + 69 %) in the ruminal fluid. When tannins were included into the concentrate, the LD contained double levels of rumenic acid (RA) as compared to the LD of the lambs fed the tannins-free concentrate (0.96 vs. 0.46 % of total extracted fatty acids, respectively; P < 0.05). The concentration of PUFA was higher (P < 0.05) and SFA (P < 0.01) lower in the LD from lambs fed the tannin diets as compared to the animals receiving the tannin-free diets. In conclusion, tannins reduce the biohydrogenation of the PUFA in the rumen. This implies that tannins supplementation could be a strategy to increase the RA and PUFA content and to reduce the SFA into ruminant meats

Influence of ewe feeding systems on meat quality of suckling lambs

In recent years interest has grown in the zootechnical exploitation of environmental feeding resources, above all in marginal areas. The survival of these areas is linked to the development of the limited available resources. Of these, natural pastures represent one of the most important, not only because their zootechnical utilisation permits savings in alimentary costs, but above all because it results in better quality dairy and meat products. The aim of this study is to verify if and to what level ewe feeding systems influence the meat quality of suckling lambs

Early onset effects of single substrate accumulation recapitulate major features of LSD in patient-derived lysosomes.

Lysosome functions mainly rely on their ability to either degrade substrates or release them into the extracellular space. Lysosomal storage disorders (LSDs) are commonly characterized by a chronic lysosomal accumulation of different substrates, thereby causing lysosomal dysfunctions and secretion defects. However, the early effects of substrate accumulation on lysosomal homeostasis have not been analyzed so far. Here, we describe how the acute accumulation of a single substrate determines a rapid centripetal redistribution of the lysosomes, triggering their expansion and reducing their secretion, by limiting the motility of these organelles toward the plasma membrane. Moreover, we provide evidence that such defects could be explained by a trapping mechanism exerted by the extensive contacts between the enlarged lysosomes and the highly intertwined membrane structures of the endoplasmic reticulum which might represent a crucial biological cue ultimately leading to the clinically relevant secondary defects observed in the LSD experimental models and patients

Competitive binding of extracellular accumulated heparan sulfate reduces lysosomal storage defects and triggers neuronal differentiation in a model of Mucopolysaccharidosis IIIB

Mucopolysaccharidoses (MPSs) are a group of inherited lysosomal storage disorders associated with the deficiency of lysosomal enzymes involved in glycosaminoglycan (GAG) degradation. The resulting cellular accumulation of GAGs is responsible for widespread tissue and organ dysfunctions. The MPS III, caused by mutations in the genes responsible for the degradation of heparan sulfate (HS), includes four subtypes (A, B, C, and D) that present significant neurological manifestations such as progressive cognitive decline and behavioral disorders. The established treatments for the MPS III do not cure the disease but only ameliorate non-neurological clinical symptoms. We previously demonstrated that the natural variant of the hepatocyte growth factor NK1 reduces the lysosomal pathology and reactivates impaired growth factor signaling in fibroblasts from MPS IIIB patients. Here, we show that the recombinant NK1 is effective in rescuing the morphological and functional dysfunctions of lysosomes in a neuronal cellular model of the MPS IIIB. More importantly, NK1 treatment is able to stimulate neuronal differentiation of neuroblastoma SK-NBE cells stable silenced for the NAGLU gene causative of the MPS IIIB. These results provide the basis for the development of a novel approach to possibly correct the neurological phenotypes of the MPS IIIB as well as of other MPSs characterized by the accumulation of HS and progressive neurodegeneration

Lamb meat oxidative stability as affected by the length of concentrate-based finishing diet

This study was designed to assess the effect of the duration of feeding lambs with concentrates in stall after a period of pasture feeding on meat oxidative stability. Thirty-eight Italian Merino lambs were divided into 4 groups at 60 days of age. Over 89 days, 10 lambs (S group) were fed concentrates in stall, while 9 ani- mals (P group) grazed herbage at pasture. Ten lambs (P-S37 group) and 9 lambs (P-S14 group) initially grazed together with animals in the P group, but were housed in stall and fed as the S group for 37 and 14 days before slaughtering, respectively. Lipid oxidation was measured as TBARS (mg of malonaldehyde / kg of meat) on slices of raw muscle Longissimus dorsi and on cooked minced muscle over 8 and 2 days of storage at 4°C, respectively. After 8 days of storage, lower TBARS values were found in raw muscle from lambs in the P group (0.70) compared to the S, P- S14 and P-S37 groups (2.32, 2.13 and 3.09, respectively; P <0.0005), while meat from lambs in the P-S37 group displayed higher TBARS values compared to S and P-S14 groups (P < 0.05). After 2 days of storage, TBARS values in cooked meat from S, P- S14 and P-S37 groups (2.48, 2.03 and 2.41, respectively) did not differ, but were higher compared to the P group (1.47; P < 0.05). These results suggest that possible modifications of the balance between pro-oxidant and antioxidant components in muscle may be responsible for a different lipid stability between meat from lambs fed exclusively herbage at pasture and meat from animals fed exclusively concentrates or finished on concentrates after a period of pasture feeding