Assessment of cecal microbiota modulation from piglet dietary supplementation with copper.

BACKGROUND: Swine production expanded in the last decades. Efforts have been made to improve meat production and to understand its relationship to pig gut microbiota. Copper (Cu) is a usual supplement to growth performance in animal production. Here, two performance studies were conducted to investigate the effects of three different sources of Cu on the microbiota of piglets. A total of 256 weaned piglets were randomly allocated into 4 treatments (10 replicates per treatment of 4 piglets per pen in Trial 1 and 8 replicates of 3 piglets per pen in Trial 2). Treatments included a control group (fed 10 mg/kg of Cu from CuSO4), a group fed at 160 mg/kg of Copper (II) sulfate (CuSO4) or tri-basic copper chloride (TBCC), and a group fed with Cu methionine hydroxy analogue chelated (Cu-MHAC) at 150, 80, and 50 mg/kg in Phases 1 (24-35 d), 2 (36-49 d), and 3 (50-70 d), respectively. At 70 d, the cecum luminal contents from one pig per pen were collected and polled for 16 S rRNA sequencing (V3/V4 regions). Parameters were analyzed in a completely randomized block design, in which each experiment was considered as a block. RESULTS: A total of 1337 Operational Taxonomic Units (OTUs) were identified. Dominance and Simpson ecological metrics were statistically different between control and treated groups (P < 0.10) showing that different Cu sources altered the gut microbiota composition with the proliferation of some bacteria that improve gut health. A high abundance of Prevotella was observed in all treatments while other genera were enriched and differentially modulated, according to the Cu source and dosage. The supplementation with Cu-MHAC can modify a group of bacteria involved in feed efficiency (FE) and short chain fatty acids (SCFA) production (Clostridium XIVa, Desulfovibrio, and Megasphera). These bacteria are also important players in the activation of ghrelin and growth hormones that were previously reported to correlate with Cu-MHAC supplementation. CONCLUSIONS: These results indicated that some genera seem to be directly affected by the Cu source offered to the animals. TBCC and Cu-MHAC (even in low doses) can promote healthy modifications in the gut bacterial composition, being a promising source of supplementation for piglets.

Modified atmosphere packaging for lamb meat: evaluation of gas composition in the extension of shelf life and consumer acceptance.

Convenience foods like chilled meat usually have a short shelf life. Modified atmosphere packaging (MAP) can be used together with refrigeration to retard meat degradation. This work evaluated the effect of MAP on the preservation and consumers acceptance of lamb meat. Lamb loins Longissimus lumborum were packed in five conditions: 15% O2 + 85% CO2 (O15), 30% O2 + 70% CO2 (O30), 45% O2 + 55% CO2 (O45), 60% O2 + 40% CO2 (O60), and Vacuum (control). Physicochemical, sensory, and microbiological analyses were carried out along 21 days of refrigerated (1 ± 1 °C) storage. Treatments O30, O45 and vacuum presented the lowest oxidation values: 0.60, 0.61 and 0.30 Malonaldehyde Kg-1 respectively. Treatment O45 showed the highest a* until the seventh day of storage (16.64). In the sensory preference ranking test, O30 and O45 received best scores in the first and second weeks of storage, respectively. Treatments O30 and O45 delivered products with lower microbial counts than the other ones. Considering a balance between consumer preference and microbiological results, we propose the use of 45% O2 + 55% CO2 gas composition to extend the shelf life of lamb loin.

Microencapsulated jabuticaba (Myrciaria cauliflora) extract added to fresh sausage as natural dye with antioxidant and antimicrobial activity.

The aim was to evaluate the addition of microencapsulated jabuticaba extract (MJE) to fresh sausage as natural dye with antioxidant and antimicrobial activity. Fresh sausages without dye, with cochineal carmine and with addition of 2% and 4% MJE were evaluated for chemical, microbiological and sensory properties during 15days of refrigerated storage. TBARS values were lower (P<0.05) throughout the storage period in sausages with 2% and 4% MJE (below 0.1mg of malondialdehyde/kg sample) than in control and carmine treatments (from 0.3 to 0.6mg of malondialdehyde/kg sample). T2% and T4% also showed lower microbial counts on storage days 4 and 15 for APCs. The addition of 4% MJE negatively influenced (P<0.05) sensory color, texture and overall acceptance attributes. On the other hand, T2% presented similar (P>0.05) sensory acceptance to control and carmine treatments in most of the attributes evaluated except for a decrease in color. Thus, addition of 2% MJE to fresh sausage can be considered as a natural pigment ingredient.