Microencapsulated dietary supplementation coupled with sexual inversion improves the immune and antioxidant response of Nile tilapia larvae under stressful conditions.

In tilapia aquaculture, the cultivation of single-sex animals is extremely widespread, as it allows for the standardization of lots, in addition to improving the general performance of the animals. However, it is possible that hormonal inversion interacts with other factors, such as environmental and nutritional management, and modulates the immune response and antioxidant system of animals in a distinct manner. In order to test this hypothesis, an experiment was carried out using Nile tilapia larvae six days after hatching, divided into four experimental groups: NI (non-inverted animals), I (sexual inverted animals), NI + M (non-inverted supplemented with microencapsulated products) and I + M (sexual inverted and supplemented with microencapsulated products; half of which were subjected to transportation-related stress after 28 days of the experiment. At the end, the survival rate was evaluated; the gene expression of heat shock protein (HSP70), interleukin 1 beta (IL-1ß) and cyclooxygenase-2 (COX 2) via RT-PCR; also evaluated were the activity of catalase (CAT) and superoxide dismutase (SOD) enzymes, as well as the total antioxidant capacity by 2,2-diphenyl-1-picryl-hydrazyl (DPPH). Animals from the I and I + M groups had the highest survival rate (p < 0.001) regardless of transportation stress. The highest expressions of HSP70 were found in the NI group (p < 0.001, with and without transportation). For the IL-1ß gene, there was an increase in expression for animals belonging to groups NI and NI + M (no transportation); and NI (p < 0.0001, with transportation). Increased COX 2 expression was observed for all groups after transportation (p < 0.0001). The highest SOD activities were observed in groups I and I + M (without transportation, p = 0.0004), and I (with transportation, p < 0.0001). The transportation decreased the total antioxidant capacity of DPPH in all treatments (p < 0.001). Finally, when evaluating all of the results together, we came to a conclusion that sex inversion improves the immune response and antioxidant profile of animals under stressful conditions when associated with microencapsulated dietary supplementation.

Carcass characteristics and meat evaluation of cattle finished in temperate pasture and supplemented with natural additive containing clove, cashew oil, castor oils, and a microencapsulated blend of eugenol, thymol, and vanillin.

BACKGROUND: Forty crossbred steers were supplemented with different doses (from 0 control to 6000 mg/animal/day) of natural additive blend containing clove essential oil, cashew oil, castor oil, and a microencapsulated blend of eugenol, thymol, and vanillin for 80 days. Carcass characteristics, drip loss, and antioxidant activity were evaluated 24 h post mortem on longissimus thoracis, and the effects of aging (until 14 days) were evaluated for water losses (thawing/aging and cooking), texture, color, and lipid oxidation. RESULTS: The use of the natural additive blend did not modify (P > 0.05) carcass characteristics but did, however, modify body composition (P < 0.05). Drip losses were unaffected by the treatments tested (P > 0.05). There was an observed quadratic effect (P < 0.05) on losses from thawing/aging on the first day of storage. Regarding the effects of natural additives on cooking losses, there was a quadratic effect (P < 0.05) among the treatments on day 7 of aging. Differences between days of aging were only observed with control treatment. Shear force was similar among treatments on days 1 and 7 of aging. On day 14 a linear effect (P < 0.05) was observed. Also, a linear effect (P < 0.05) appeared on meat lightness, meat from the control group being clearer on day 1. No changes were observed in redness among treatments or days of storage (P > 0.05). Yellowness was not modified by the treatments (P > 0.05)but only by the days of storage in control and the lowest dosage used. CONCLUSION: The blend of natural additives has potential use in pasture feeding and could improve meat quality. However, doses should be adjusted. © 2021 Society of Chemical Industry.

Meat quality of young bulls finished in a feedlot and supplemented with clove or cinnamon essential oils.

Forty young crossbred bulls (10 ± 2.2 months of age; 219 ± 11.7 kg) were finished in a feedlot with one of five different treatments: CON, control (no essential oil); CLO450, clove essential oil (450 mg/kg); CLO880, clove essential oil (880 mg/kg); CIN450; cinnamon essential oil (450 mg/kg); and CIN880, cinnamon essential oil (880 mg/kg). Instrumental meat quality attributes and consumer acceptability aspects (visual and sensory) were assessed during meat ageing and display. The inclusion of clove essential oil showed (P = 0.033) a quadratic effect on lipid oxidation in meat evaluated under display conditions. Level of cinnamon essential oil affected (P < 0.05) pH, shear force, and meat colour. On the other hand, the diet had no effect (P > 0.05) on sensory or visual acceptability. Ageing (7 days) enhanced (P < 0.05) sensory acceptability attributes. Globally, the addition of essential oil in bull diets can be an alternative to reduces lipid oxidation without modifying sensory acceptability attributes.

Improvements in the quality of meat from beef cattle fed natural additives.

Forty young bulls were fed with five different treatments (n = 8, 62 days): control, without the addition of natural additives (CON); NA15, a mixture of natural additives (1.5 g/animal/day); NA30, a mixture of natural additives (3.0 g/animal/day); NA45, a mixture of natural additives (4.5 g/animal/day); and NA60, a mixture of natural additives (6.0 g/animal/day). The hot carcass weight and dressing percentage, fat thickness, Longissimus muscle area, marbling, pH, and carcass tissue composition were measured. In addition, the instrumental meat quality (colour, water holding capacity, texture and lipid oxidation) and consumer acceptability attributes, across display were evaluated. Diet had no effect (P > .05) on the carcass characteristics evaluated (except pH). The diets significantly influenced the pH, shear force, tenderness, lipid oxidation and overall acceptability evaluated by consumers (P < .05). Globally, natural additives have some potential use in animal feed to improve meat quality.