[Persistence, internalization and translocation of Escherichia coli O157:H7, O157:H16 and O105ab in plants and tomato fruits (Solanum lycopersicum L.)]. / Persistencia, internalización y translocación de Escherichia coli O157:H7, O157:H16 y O105ab en plantas y frutos de tomate (Solanum lycopersicum L.).

The presence of pathogenic bacteria, such as Escherichia coli affects the quality and safety of vegetables that are consumed fresh and is associated with serious health problems. The objective of this study was to determine if three different strains of E. coli can penetrate and remain in plants and tomato fruits. A completely randomized experimental design was followed for which a tomato crop ("Cid" variety) was established under greenhouse conditions and three treatments were evaluated, T1 (E. coli O157:H7), T2 (E. coli from tomato cultivation [EcT] O157:H16), T3 (E. coli from spinach cultivation [EcH] O105ab) and a T4 control, with 100 plants each and four forms of inoculation: in the substrate, steam, petiole and the peduncle. Samples were carried out in vegetative stage, flowering, fruiting and physiological maturity to quantify in petri dish CFU/g and know if the bacteria managed to move around and recover in root, stem, flower and fruit. The phylogenetic groups that corresponded to the bacteria recovered were confirmed by biochemical tests, serotyping and PCR. At 120 days the recovery of bacteria in the plant was 23% (E. coli O157:H7), 28% (EcT O157:H16) and 55% (EcH O105ab) whit inoculation to the substrate while the inoculation by puncture the recovery was (in the same order) of 5%, 3%, and 4% at 30 days; 37%, 35% and 30% at 90 days; and 42%, 39% and 13% at 65 days. The strains submit the ability to enter the tomato plant and to stay in it and transported to the fruit, without producing that indicate their presence.

Effect of Mid-Term Dietary Administration of the Caesalpinia coriaria Extract on the Sustainable Mitigation of Equine Fecal Methane, Carbon Monoxide and Hydrogen Sulfide Production.

This study aimed to evaluate the dietary administration of the Caesalpinia coriaria (CC) extract for 30 days on in vitro fecal greenhouse gases production. Fecal samples, as inoculums, were collected from horses given daily 0- (Fecal 0), 60- (Fecal 60) and 120- (Fecal 60) mL CC aqueous extract per animal. The extract dose was mixed with the morning feeding diet at 6:00 h for each horse. During incubation, 0-, 0.6-, 1.2- and 1.8-mL CC extracts were added to the basal diet which was fed to horses (as subtract) and evaluated with each fecal type. Feces from the horses given no CC extract produced the lowest (P = .0014) methane while the fecal from horses given CC produced more methane . It was also observed that all CC doses linearly (P = .0457) produced more methane than the control. Furthermore, Fecal 0 was more efficient and produced less methane for every unit of metabolizable energy, organic matter, and short chain fatty acids while Fecal 60 was the least efficient. Production of H2S showed that feces of equine orally give 60 mL/day CC produced the highest while Fecal 0 and Fecal 120 were similar. Fecal type x dose showed that 0 mL/g DM produced the highest H2S while 1.8 mL/g DM produced the lowest. Thus, based on gas production, H2S, CO and CH4, feeding horses with 60 mL/day of CC with or without 0.6 mL/g DM of CC extract is recommended for the sustainable mitigation of greenhouse gases emission in horses.

Persistencia, internalización y translocación de Escherichia coli O157:H7, O157:H16 y O105ab en plantas y frutos de tomate (Solanum lycopersicum L.) / Persistence, internalization and translocation of Escherichia coli O157:H7, O157:H16 and O105ab in plants and tomato fruits (Solanum lycopersicum L.)

La presencia de bacterias patógenas, como Escherichia coli, afecta la calidad e inocuidad de las hortalizas que se consumen en fresco y se relaciona con graves problemas de salud. El objetivo de este trabajo fue determinar si 3 cepas diferentes de E. coli tienen la capacidad de penetrar y permanecer en plantas y frutos de tomate. Se siguió un diseño experimental completamente al azar, para lo cual se estableció un cultivo de tomate (variedad «Cid¼) en condiciones de invernadero y se evaluaron 3 tratamientos, T1 (E. coli O157: H7), T2 (E. coli de cultivo de tomate -#91;EcT-#93; O157: H16), T3 (E. coli de cultivo de espinaca -#91;EcH-#93; EcH O105ab) y un testigo T4, con 100 plantas cada uno y 4 formas de inoculación: en el sustrato, en el tallo, en el pecíolo y en el pedúnculo. Se realizaron muestreos en etapa vegetativa, floración, fructificación y madurez fisiológica para cuantificar en placa las UFC/g y saber si las bacterias lograban moverse y recuperarse en la raíz, el tallo, la flor y el fruto. Los grupos filogenéticos a los que correspondieron las bacterias recuperadas fueron confirmados mediante pruebas bioquímicas, serotipificación y PCR. A los 120 días la recuperación de bacterias en la planta fue del 23% (E. coli O157: H7), 28% (EcT O157: H16) y 55% (EcH O105ab) con la inoculación al sustrato, mientras que con la inoculación por punción la recuperación fue (en igual orden) del 5%, 3% y 4% a los 30 días; del 37%, 35% y 30% a los 90 días; y del 42%, 39% y 13% a los 65 días. Las cepas utilizadas mostraron la capacidad de entrar en la planta de tomate y de permanecer en ella y transportarse hasta llegar al fruto, sin producir síntomas que indiquen su presencia.

The presence of pathogenic bacteria, such as Escherichia coli affects the quality and safety of vegetables that are consumed fresh and is associated with serious health problems. The objective of this study was to determine if three different strains of E. coli can penetrate and remain in plants and tomato fruits. A completely randomized experimental design was followed for which a tomato crop ("Cid" variety) was established under greenhouse conditions and three treatments were evaluated, T1 (E. coli O157: H7), T2 (E. coli from tomato cultivation -#91;EcT-#93; O157: H16), T3 (E. coli from spinach cultivation -#91;EcH-#93; O105ab) and a T4 control, with 100 plants each and four forms of inoculation: in the substrate, steam, petiole and the peduncle. Samples were carried out in vegetative stage, flowering, fruiting and physiological maturity to quantify in petri dish CFU/g and know if the bacteria managed to move around and recover in root, stem, flower and fruit. The phylogenetic groups that corresponded to the bacteria recovered were confirmed by biochemical tests, serotyping and PCR. At 120 days the recovery of bacteria in the plant was 23% (E. coli O157: H7), 28% (EcT O157: H16) and 55% (EcH O105ab) whit inoculation to the substrate while the inoculation by puncture the recovery was (in the same order) of 5%, 3%, and 4% at 30 days; 37%, 35% and 30% at 90 days; and 42%, 39% and 13% at 65 days. The strains submit the ability to enter the tomato plant and to stay in it and transported to the fruit, without producing that indicate their presence.