Effects of different antioxidants on quality of beef patties from steers fed low-moisture distillers grains.

This research evaluated the effects of different antioxidants on overall quality of beef patties from steers fed distillers grains. Crossbred steers (n = 24) were fed corn, 40% Dry distillers grains plus solubles, or 40% modified distillers grains plus solubles - Dry Matter basis). Patties were made from ground chuck of individual animals and 4 antioxidant treatments were evaluated (CONTROL - no antioxidant, 0.3% ROSEMARY, 0.25% ACEROLA, and 0.6% CITRUS). Diets minimally affected quality attributes. Patties treated with ROSEMARY were shown significant lighter in color than other treatments on day 6. Patties treated with CITRUS were the reddest on days 5 and 6 of display. ACEROLA and CITRUS provided better lipid stability during display when compared to CONTROL and ROSEMARY. Treatment CITRUS reduced APC growth by 2 log when compared to all other treatments (P < 0.01). Although patties treated with CITRUS had higher off-flavor intensity, no effect was observed for overall desirability. Patties treated with 0.6% of CITRUS provided optimal overall quality.

A comparison of consumer sensory acceptance and value of domestic beef steaks and steaks from a branded, Argentine beef program.

To determine consumer sensory acceptance and value of branded, Argentine (grass-finished, aged 30+ d) and domestic (U.S. grain-finished beef, aged 9 d) strip loins were paired based on similar Warner-Bratzler shear force values (P = 0.34) and similar marbling levels (P = 0.82). Consumers in Chicago, IL, and San Francisco, CA (n = 124 per city), evaluated one pair of Argentine and domestic steaks, and had the opportunity to participate in a silent, sealed-bid auction to purchase steaks matching the taste panel samples. Consumers were categorized into three groups based on overall acceptability ratings: 1) those who found Argentine steaks more acceptable, 2) those who found domestic steaks more acceptable, and 3) those who were indifferent. Consumers rated domestic steaks higher (P < 0.05) in juiciness, tenderness, flavor, and overall acceptability. Consumers in both Chicago and San Francisco were willing to pay more (P < 0.05) for domestic steaks (0.86 dollars and 0.52 dollars per 0.45 kg, respectively). In both cities, consumers who found Argentine samples more acceptable were willing to pay more (P < 0.05) for Argentine steaks (0.74 dollars per 0.45 kg in Chicago and 1.82 dollars per 0.45 kg in San Francisco), and consumers who found domestic samples more acceptable were willing to pay more (P < 0.05) for domestic steaks (1.66 dollars per 0.45 kg in Chicago and 1.34 dollars per 0.45 kg in San Francisco). Consumers who were indifferent were willing to pay similar (P = 0.99) amounts for Argentine and domestic steaks. Although some consumers found Argentine beef more acceptable than domestic beef (19.7 and 16.5% in Chicago and San Francisco, respectively) and were willing to pay more for it, most consumers found domestic beef to be more acceptable (59.0% in Chicago and 61.5% in San Francisco) and were willing to pay more to obtain a more acceptable product.

Effects of gamma radiation on the sterility and behavioral quality of the caribbean fruit fly, Anastrepha suspensa (Loew) (Diptera:Tephritidae)

Pupae of Anastrepha suspensa (Loew) were irradiated 2 days before adult eclosión in an air atmosphere with 15, 20, 25, 30, 50 and 70 Gy of gamma radiation (Co-60). The radiation effects on sterility and other parameters of quality and behavior of males and females of caribfly were established. Males became fully sterile with a dose of 50 Gy and females laid no eggs when exposed to 25 Gy. Radiation had no significant effect on adult eclosion, sex ratio, flight ability and irritability, but female mortality was affected significantly by radiation, showing higher survival rates in low dosage treatments. The mating behavior of the males was reduced significantly by increasing the radiation doses.

Pupas de Anastrepha suspensa (Loew) foram irradiadas dois dias antes da emergência dos adultos em atmosfera de ar com as doses de 15, 20, 25, 30, 50 e 70 Gy de radiação gama (Co-60). Foram avaliados os efeitos da radiação sobre a esterilidade e outros parâmetros de qualidade e comportamento de machos e fêmeas de mosca-do-caribe. Machos tornaram-se totalmente estéreis com uma dose de 50 Gy e as fêmeas não ovipositaram quando expostas a 25 Gy. A radiação não teve efeito significativo sobre a taxa de emergência de adultos, na razão sexual, na habilidade de vôo e na irritabilidade desses insetos. Somente a mortalidade das fêmeas foi afetada significativamente pela radiação, causando unia maior sobrevivência nas dosagens mais baixas. A atividade de acasalamento dos machos foi reduzida significativamente com o incremento da dosagem de radiação.

Effects of gamma radiation on the sterility and behavioral quality of the caribbean fruit fly, Anastrepha suspensa (Loew) (Diptera:Tephritidae)

Pupae of Anastrepha suspensa (Loew) were irradiated 2 days before adult eclosión in an air atmosphere with 15, 20, 25, 30, 50 and 70 Gy of gamma radiation (Co-60). The radiation effects on sterility and other parameters of quality and behavior of males and females of caribfly were established. Males became fully sterile with a dose of 50 Gy and females laid no eggs when exposed to 25 Gy. Radiation had no significant effect on adult eclosion, sex ratio, flight ability and irritability, but female mortality was affected significantly by radiation, showing higher survival rates in low dosage treatments. The mating behavior of the males was reduced significantly by increasing the radiation doses.

Pupas de Anastrepha suspensa (Loew) foram irradiadas dois dias antes da emergência dos adultos em atmosfera de ar com as doses de 15, 20, 25, 30, 50 e 70 Gy de radiação gama (Co-60). Foram avaliados os efeitos da radiação sobre a esterilidade e outros parâmetros de qualidade e comportamento de machos e fêmeas de mosca-do-caribe. Machos tornaram-se totalmente estéreis com uma dose de 50 Gy e as fêmeas não ovipositaram quando expostas a 25 Gy. A radiação não teve efeito significativo sobre a taxa de emergência de adultos, na razão sexual, na habilidade de vôo e na irritabilidade desses insetos. Somente a mortalidade das fêmeas foi afetada significativamente pela radiação, causando unia maior sobrevivência nas dosagens mais baixas. A atividade de acasalamento dos machos foi reduzida significativamente com o incremento da dosagem de radiação.

Evidence for regulation of the autoimmune anti-erythrocyte response by idiotype-specific suppressor T cells in NZB mice.

The present study demonstrates that specific CD8+, CD4- suppressor T cells (Ts) actively regulate the autoimmune anti-mouse red blood cell (MRBC) antibody response in spleen cell populations of young, Coombs-negative NZB mice. These Ts appear to bind a monoclonal NZB autoantibody (G-8 mAb) to unmodified MRBC which expresses a dominant idiotype (Id) in the spontaneous anti-MRBC autoantibody response of NZB mice. Treatment of normally nonauto-responsive spleen cells from young NZB mice with the G-8 mAb + C prior to culture allows these cells to develop, in 4-5 days, an autoantibody response to MRBC. The level of response obtained after depletion of the G-8-binding cells is comparable with that obtained after generalized depletion of Ts by treatment with anti-CD8 + C, suggesting that the G-8-binding cells make up a major portion of the regulatory Ts in this response. Yet, G-8 + C treatment depletes a very small subset of cells and not the total CD8+ T cell population. The regulatory cells appear to be neither isotype nor allotype specific, nor do they appear to have MRBC antigens bound to or expressed on their membranes. Rather, these cells are more likely G-8 idiotype specific. The regulatory G-8-binding cells are CD8+ T cells, not B cells. Furthermore, Ts-enriched populations when depleted of G-8-binding cells lose their ability to suppress in vitro anti-MRBC responses of spleen cells from Coombs-negative NZB mice depleted of CD8+ cells, as well as those of unfractionated spleen cells from Coombs-positive NZB mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Suppressor T cells and self-tolerance. Active suppression required for normal regulation of anti-erythrocyte autoantibody responses in spleen cells from nonautoimmune mice.

Spleen cells from young, nonautoimmune strains of mice cultured with syngeneic E do not develop a significant anti-mouse E response in vitro, consistent with a state of self-tolerance to this Ag. In order to study the role of active suppression in regulating mouse RBC-(MRBC) specific cells in nonautoimmune cell populations, the effect of depleting T cell subsets on the generation of anti-MRBC autoantibodies by nonautoimmune spleen cells was determined. Spleen cells from young BALB/c and C57BL/6 mice were found to generate significant numbers of IgM and IgG anti-MRBC autoantibody-forming cells in culture with MRBC after depletion of Ly-2+ cells by anti-Ly-2 and C treatment. The response which develops is Ag dependent, Ag specific, and dependent upon L3T4+ Th. The magnitude and isotype of this response is similar to the anti-MRBC response generated by spleen cells from 12-mo-old, autoimmune NZB mice and young NZB mice also treated to remove Ly-2+ cells. Addition of isolated Ly-2+ T cells, but not L3T4+ or Ly-2- T cells, to spleen cells depleted of Ly-2+ cells restores apparently normal regulation of the anti-MRBC response in vitro. These data demonstrate that control of a specific autoantibody response to MRBC by nonautoimmune spleen cell populations requires active regulation by an Ly-2+ T cell subset.