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Sheep meat is an essential element within the multicultural mosaic of Mexican agri-food traditions. A total of 332 consumers were surveyed face-to-face in restaurants specializing in selling traditional sheep meat products. Our results showed that consumers could be segmented based on their perceptions, habits, and preferences towards sheep meat. For consumers, sheep meat is perceived as food with unique sensory attributes, coming from healthier animals than other species and traditional characters. Their willingness to pay extra is subject to the guarantee that the meat is safe, free of hormones and antibiotics, and to a lesser extent, certified organic. The multivariate analysis suggested three clusters or consumer profiles named passive, wholehearted, and deep-rooted, which explained the associations among attitudes, some demographic variables, and consumption frequency. The nascent national sheep meat industry needs to consider these concerns in developing marketing and trust strategies to attract, maintain, and build loyalty among Mexican consumers.

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AIMS: The influence of Lactobacillus farciminis on ruminal fermentation characteristics was elucidated in this study. METHODS AND RESULTS: Ruminal fermentation was conducted using maize silage ration (R) and concentrate (C) as 75R:25C, 50R:50C and 25R:75C, supplemented with lactic acid bacteria (LB) at 0, 20 and 30 mg g-1 dry matter substrate and their interaction (1st experiment). The same LB product was used at 0, 20, 40 and 60 mg g-1 dry matter of the mixture (1 : 1) of oat straw and concentrate for 48 h of incubation (2nd experiment). At 24 and 48 h of incubation, LB0 produced the highest biogas and LB20 produced the lowest, whereas at 48 h of incubation LB40 produced the lowest. In ration x LB, LB40 resulted in the highest biogas production, while LB0 had the lowest (P < 0·001) at 8, 10 and 12 h of incubation. Inclusions of LB0, 20, 40 and 60 mg g-1 dry matter resulted in a linear increase (P < 0·003) in the asymptotic biogas production and fermentation parameters in a dose-dependent manner, except in pH which decreased (P = 0·029). CONCLUSIONS: The use of L. farciminis in diet with high level of concentrate without any adverse effect on the pH of rumen fluid to the point of acidosis. Furthermore, in high forage diet, the use of L. farciminis would help to improve the ruminal fermentation digestibility and mitigate ruminal biogas production. SIGNIFICANCE AND IMPACT OF THE STUDY: Using Lactobacillus as a feed additive can improve ruminal fermentation activities by maintaining the stability of pH in the rumen and improving the feed utilization through manipulation of the microbial ecosystem.

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The present context was designed to investigate the efficacy of devil fish (DF; Plecostomus sp.) silage and Staphylococcus saprophyticus on fermentation characteristics as well as greenhouse gases production mitigation attributes in horses. Four levels of ensiled DF at 0 (control DF0), 6 (DF6), 12 (DF12), and 18 (DF18) % were added into the diet. Moreover, three doses of S. saprophyticus (0, 1, and 3 mL/g dry matter [DM]) were used for in vitro fecal fermentation. The use of ensiled DF resulted in increased (P < .0001) pH during fermentation. The asymptotic gas production was the highest (P < .0001) in DF6, whereas other supplementation caused lower production than that of control. Lag time for the asymptotic gas production decreased (P < .05) with increasing dietary DF doses. Inclusion of S. saprophyticus resulted in the lowest (P < .05) gas production and mL/0.5 g DM incubated and thus, the reduced gas production up to 23.17% than that of control. The interaction of DF × S. saprophyticus showed the lowest gas production at DF18, whereas the highest production was estimated at DF6 without S. saprophyticus after 48 hours. The lowest emission of CO2 (P < .0001) was observed in DF18 inclusion, which was 15.25% lower than that of control at 48 hours of fermentation. In contrast, the lowest hydrogen (H2) production was estimated in DF0, whereas DF18 exhibited the highest. Inclusion of DF12 and DF18 reduced (P < .05) methane (CH4) emission by 58.24% and 59.33%, respectively. However, DF, S. saprophyticus, and DF × S. saprophyticus interaction had no significant effect (P > .05) on CH4 production. In conclusion, ensiled DF and S. saprophyticus could be supplemented in equine diet as promising alternatives to corn for mitigating the emission of greenhouse gases effectively.

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BACKGROUND: Ticks are a problem for cattle production mainly in tropical and subtropical regions, because they generate great economic losses. Acaricides and vaccines have been used to try to keep tick populations under control. This has been proven difficult given the resistance to acaricides and vaccines observed in ticks. Resistance to protein rBm86-based vaccines has been associated with the genetic diversity of Bm86 among the ectoparasite's populations. So far, neither genetic diversity, nor spatial distribution of circulating Bm86 haplotypes, have been studied within the Mexican territory. Here, we explored the genetic diversity of 125 Bm86 cDNA gene sequences from R. microplus from 10 endemic areas of Mexico by analyzing haplotype distribution patterns to help in understanding the population genetic structure of Mexican ticks. RESULTS: Our results showed an average nucleotide identity among the Mexican isolates of 98.3%, ranging from 91.1 to 100%. Divergence between the Mexican and Yeerongpilly (the Bm86 reference vaccine antigen) sequences ranged from 3.1 to 7.4%. Based on the geographic distribution of Bm86 haplotypes in Mexico, our results suggest gene flow occurrence within different regions of the Mexican territory, and even the USA. CONCLUSIONS: The polymorphism of Bm86 found in the populations included in this study, could account for the poor efficacy of the current Bm86 antigen based commercial vaccine in many regions of Mexico. Our data may contribute towards designing new, highly-specific, Bm86 antigen vaccine candidates against R. microplus circulating in Mexico.

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BACKGROUND: During human pregnancy, infection/inflammation represents an important factor that increases the risk of developing preterm labor. The purpose of this study was to determine if pre-treatment with progesterone has an immunomodulatory effect on human placenta production of endotoxin-induced inflammation and degradation of extracellular matrix markers. METHODS: Placentas were obtained under sterile conditions from pregnancies delivered at term before the onset of labor by cesarean section. Explants from central cotyledons of 10 human placentas were pre-treated with different concentrations of progesterone (0.01, 01, 1.0 µM) and then stimulated with 1000 ng/mL of LPS of Escherichia coli. Cytokines TNFα, IL-1ß, IL-6, IL-8, MIP-1α, IL-10 concentrations in the culture medium were then measured by specific ELISA. Secretion profile of MMP-9 was evaluated by ELISA and zymogram. Statistical differences were determined by one-way ANOVA followed by the appropriate ad hoc test; P < 0.05 was considered statistically significant. RESULTS: In comparison to the explants incubated with vehicle, the LPS treatment led to a significant increase in the level of all cytokines. In comparison to the explants treated only with LPS, pre-treatment with 0.01-1.0 µM progesterone significantly blunted (73, 56, 56, 75, 25, 48 %) the secretion of TNF-α, IL-1ß, IL-6, IL-8, MIP-1α, IL-10, respectively. The MMP-9 induced by LPS treatment was inhibited only with the highest concentration of progesterone. Mifepristone (RU486) blocked the immunosuppressive effect of progesterone. CONCLUSIONS: The present results support the concept that progesterone could be part of the compensatory mechanism that limits the inflammation-induced cytotoxic effects associated with an infection process during gestation.

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OBJECTIVE: To evaluate whether progesterone (P4) is able to modulate the secretion of tumour necrosis factor α (TNF-α), interleukin-1ß (IL-1ß), IL-6, IL-8, IL-10 and matrix metalloproteinase-9 (MMP-9) after choriodecidual stimulation with lipopolysaccharide (LPS). DESIGN: Chorioamnionitis-elicited preterm delivery is associated with an uncontrolled secretion of proinflammatory cytokines that may induce MMPs, which modify the fine immunological and structural equilibrium at the fetal-maternal interface. SETTING: Instituto Nacional de Perinatología 'Isidro Espinosa de los Reyes', Mexico City. SAMPLE: Twelve human fetal membranes at term from healthy patients were placed in a two-chamber culture system. METHODS: Choriodecidual and amniotic regions were preincubated with 1.0, 0.1, or 0.01 µmol/l P4 for 24 hours; after which the choriodecidual region was costimulated with 1000 ng/ml of LPS for 24 hours. MAIN OUTCOME MEASURES: Descriptive statistics were obtained for each variable. Data distribution was tested for normality using Kolmogorov-Smirnoff and Shapiro-Wilk tests. When distribution was normal, Student's t test was used to analyse for differences among groups. Mann-Whitney's U test was used when data were not normally distributed. RESULTS: Pretreatment with 1.0 µmol/l P4 significantly blunted the secretion of TNF-α, IL-1ß, IL-6, IL-8 and IL-10. MMP-9 was inhibited with 0.1 µmol/l P4. Mifepristone (RU486) blocked the immunosuppressive effect of P4, suggesting a P4 effect mediated by its receptor. CONCLUSION: These results offer evidence to support the concept that P4 can protect the fetal-placental unit through a compensatory mechanism that partially limits the secretion of proinflammatory and prodegradative modulators.

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INTRODUCTION: Recently, it has been proposed that supplementation with l-Arginine reduces the incidence of preeclampsia in high risk women, but the molecular mechanisms involved in the protective effect need to be determined. In addition, a critical role of l-Arginine in endothelial cell survival during oxidative stress, and the participation of neutrophils in the induction of oxidative stress during preeclampsia have been suggested. OBJECTIVES: To address if supplementation with l-arginine provides antioxidant defense in human vascular endothelial cells. METHODS: Human vascular endothelial cells (HUVECs) were isolated from umbilical cord veins obtained from healthy women underwent cesarean sections at term, with no evidence of hypertension disorders through the pregnancy. HUVECs were cultured in EndoGro media with LS supplement kit and 1% antibiotic with (n=10) or without 200uM l-Arginine (n=10). Confluent HUVECs were stimulated with neutrophils activated with 50umol/L arachidonic acid (1:16 ratio of neutrophil/cells). After incubation, cells were rinsed in PBS and harvested for RNA and protein extraction. Reverse transcription was performed using the RT(2) First Strand kit, and expression gene profiling was generated using the RT(2) Profiler PCR Array Human Oxidative Stress and Antioxidant Defense that includes the expression profile of 84 genes related to the oxidative pathway. Expression results were analyzed with the RT(2) Profiler PCR Array Data Analysis Template v3.0 and two different lists of fold change in gene expression were generated: (1) HUVEC+neutrophils vs HUVEC+l-Arginine + neutrophils and (2) HUVEC vs HUVEC+neutrophils. Validation of the expression assays was performed using western blots or ELISAS for proteins expressed by selected genes. RESULTS: Fold up- or down gene regulation are shown in Table 1. Forty six genes involved in oxidative stress defense were significantly up-regulated in HUVECs supplemented with l-arginine when were exposed to neutrophils. Interestingly, almost the same genes were down-regulated in non-supplemented HUVECs after neutrophil exposure. CONCLUSION: Supplementation with l-Arginine upregulates the expression of genes related to antioxidant defense in primary cultures of endothelial cells. This finding provides a novel insight about the molecular mechanisms involved in the protective role of l-Arginine during preeclampsia.

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