Resumen El objetivo del estudio fue predecir el riesgo potencial de exposición a V. cholerae y V. parahaemolyticus asociado al consumo de ostión americano (Crassostrea virginica) crudo colectado del Sistema Lagunar Mandinga (SLM), en restaurantes, coctelerías y puestos ambulantes. El riesgo se estimó como casos esperados/100,000 porciones con el modelo de la FDA. En ostiones del SLM el riesgo estimado por consumir ostiones contaminados con V. cholerae noO1/noO139 chxA+ sin refrigerar 10 h en verano fue bajo (99×10-5 casos); V. parahaemolyticus tdh+ y tdh+/trh+ representaron un riesgo estimado alto en primavera (2,200×10-5 y 4,000×10-5 casos, respectivamente) y la cepa pandémica orf8+ un riesgo medio (110×10-5 casos) en invierno. El consumo de ostión crudo sin refrigerar 10 h contaminado con V. cholerae noO1/noO139 chxA+ representó un riesgo promedio bajo (0.87×10-5 y 0.44×10-5 casos) para restaurantes y coctelerías, respectivamente, alto para cocteles expendidos en puestos ambulantes a temperatura ambiente 24 h (2,500×10-5 casos) y bajo a V. parahaemolyticus tdh+ en restaurantes (0.21×10-5 casos) y coctelerías (1.1×10-5 casos). El porcentaje patogénico, el sitio de venta y el tiempo sin refrigerar fueron las variables que incrementaron el riesgo de enfermar, siendo primavera la estación con el mayor riesgo para el consumidor.

Abstract The aim of the study was to assess the potential risk of exposure to V. cholerae and V. parahaemolyticus associated to raw American oyster (Crassostrea virginica) consumption collected from the Mandinga Lagoon System (MLS), in restaurants, oyster bars, and street vendors. Risk was estimated as number of cases/100,000 servings with FDA model. The risk of oyster consumption from MLS contaminated with V. cholerae noO1/noO139 chxA+ and unrefrigerated 10-h was low (99 × 10-5 cases) in summer; V. parahaemolyticus tdh+ y tdh+/trh+ estimated risk was high in spring (2,200 × 10-5 y 4,000 × 10-5 cases, respectively) and the pandemic strain orf8+ risk was medium in winter (110 × 10-5 cases). Oyster cocktail consumption unrefrigerated for 10 h and contaminated with V. cholerae noO1/noO139 chxA+, represented a low mean risk (0.87 × 10-5 and 0.44 × 10-5 cases) for oyster cocktails from restaurants and oyster bars, respectively, a high mean risk for street vendor cocktails stored at ambient temperature 24-h (2,500 × 10-5 cases), and a low mean risk for V. parahaemolyticus tdh+ in restaurants (0.21 × 10-5 cases) and oyster bar (1.1 x 10-5 cases) cocktails. Risk assessment results indicated that pathogenic percentage, type of establishment, and unrefrigerated storage time were variables that most increased the probability of illness, and spring the season with the highest risk for consumers.

Abstract This study establishes the serological frequency against Neospora caninum on day zero and the presence of N. caninum DNA surveyed throughout the gestation of Bubalus bubalis females in a bovine buffalo system in the central zone of the state of Veracruz, Mexico. Blood samples were taken from 11 females in 6 different sampling periods and analyzed for N. caninum antibodies detection on day zero. DNA detection by PCR was performed on all sampling periods. The gestation months of the females were recorded for five trimesters by ultrasonography, as well as births and pregnancy losses. Recorded seropositivity and positivity for agent DNA were 90.9% (95% CI 58.7-9.7) and 36.3% (95% CI 10.9-69.2), respectively, on day zero. N. caninum DNA was detected between 18.1% (95% CI 2.3-51.7) and 45.4% (95% CI 16.7-76.6) over the five trimesters of observation, with three births and three abortions recorded. The studied water buffalo population had a high presence of N. caninum antibodies; however, the detection of N. caninum DNA remained below 47% in the females. The association was only observed in the detection of DNA with pregnant females (P 0.007). Our results support the hypothesis of the resistance of water buffaloes to infection and the onset of clinical signs against infection by N. caninum even upon a high possibility of infection and reinfection described in this production system in Mexico.

Abstract Dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) are endocrine disruptors whose presence in milk entails a health risk. There is evidence that pasteurization decreases or increases the concentration of organochlorine pesticides in dairy products. The present research evaluated the effect of pasteurization at 63 °C 30 min-1 and 73 °C 15 sec-1 on the concentrations of DDT, HCH and their metabolites in bovine milk, in order to estimate the dietary exposure from human consumption of pasteurized milk. A completely randomized experimental design with two treatments was performed on 100 milk samples collected in Soledad de Doblado and Jamapa, Veracruz, Mexico. Pesticides were quantified by gas chromatography with an electron microcapture detector. Data were analyzed by single-factor analysis of variance (P<0.05), and means were compared with Tukey’s test (P<0.05). The dietary exposure to pesticides was assessed based on the estimated daily intake (EDI) and average daily dose (ADD) in three population groups. Pasteurization at 73 ºC reduced the concentrations of p,p'-DDE, p,p'-DDD, o,p'-DDT, p,p'-DDT and total DDT by 30.94, 44.51, 3.18, 81.23, and 42.82 %, respectively, as well as the concentrations of β-HCH, γ-HCH and total HCH (by 85.68, 18.88, and 99.31 %, respectively). The EDI of total DDT by children, adults, and elderly people was lowest for consumption of milk pasteurized at 73 °C, and that of γ-HCH, for milk pasteurized at 63 °C. The DDP of total DDT decreased with pasteurization at 73 °C. The dietary exposure to DDT and HCH was higher in children.

Resumen El diclorodifeniltricloroetano (DDT) y hexaclorociclohexano (HCH) son disruptores endocrinos cuya presencia en la leche representa un riesgo para la salud. Existe evidencia de que la pasteurización disminuye o incrementa la concentración de plaguicidas organoclorados en productos lácteos. La presente investigación evaluó el efecto de la pasteurización a 63 °C 30 min-1 y 73 °C 15 seg-1 en las concentraciones de DDT, HCH y sus metabolitos en leche bovina, para estimar la exposición dietaria por consumo humano de leche pasteurizada. Se realizó un diseño experimental completamente al azar con dos tratamientos en 100 muestras de leche recolectadas en Soledad de Doblado y Jamapa, Veracruz, México. Los plaguicidas se cuantificaron por cromatografía de gases con detector de microcaptura de electrones. Los datos se analizaron mediante análisis de varianza unifactorial (P<0.05) y las medias se compararon con Tukey (P<0.05). La exposición dietaria a plaguicidas se evaluó por la ingesta diaria estimada (IDE) y dosis diaria promedio (DDP) en tres grupos de población. La pasteurización a 73 ºC disminuyó 30.94, 44.51, 3.18, 81.23 y 42.82 % las concentraciones de p,p'-DDE, p,p'-DDD, o,p'-DDT, p,p'-DDT y DDT total, respectivamente, así como las concentraciones de β-HCH, γ-HCH y HCH total (85.68, 18.88 y 99.31 %, respectivamente). La IDE para niños, adultos y ancianos de DDT total fue menor por consumo de leche pasteurizada a 73 ºC y de γ-HCH a 63 ºC. La DDP de DDT total disminuyó con la pasteurización a 73 °C. La exposición dietaria de DDT y HCH fue mayor en niños.