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Aprovechando actividades de docencia de la Unidad de Vida Silvestre de la Facultad de Medicina Veterinaria y Zootecnia de la Universidad de San Carlos de Guatemala, se investigó la riqueza de herpetofauna de la Finca Universitaria San Julián, en Patulul, Suchitepéquez. Se emplearon 3 métodos: (1) captura/avistamiento de especímenes, (2) investigación social, (3) investigación documental. Se recorrió repetidamente un transecto de 4.5 km de longitud a través del agro paisaje de la finca. Los recorridos del transecto abarcaron un período de 10 años (2003-2013), a razón de seis sesiones por año. Cada sesión de campo consistió en un recorrido diurno y un recorrido nocturno del transecto. Se invirtieron aproximadamente 3 hr en cada recorrido diurno y 4 hr en cada recorrido nocturno. El tiempo acumulado de búsqueda fue de 420 hr-transecto. Se recorrió el equivalente a 540 km abarcando elevaciones entre 447 y 550 msnm. En cada sesión de campo participaron entre 3 y 10 personas. Tres excazadores de la finca fueron entrevistados. Se analizaron publicaciones sobre distribución de la herpetofauna para Guatemala. Se generaron dos listas que suman 97 especies. Se discute la calidad y el significado de los datos generados.

The herpetofaunal richness of San Julian Universitary Farm (FUSJ), in Patulul, Suchitepequez, Guatemala, was investigated using three methods: (1) Capture/sighting of specimens, (2) social inquiry and (3) desk research. The field work was distributed over a 10 year period (2003-2013) at a rate of six fieldwork sessions each year. A 4.5 km long transect extending through the agricultural landscape of the farm was run repeatedly. Each fieldwork session included diurnal and nocturnal travels. The accumulated search time was 420 hr-transect. The equivalent to 337.5 of accumulated miles were traveled, including elevations between 1490 and 1833 feet above sea level. Three former hunters were interviewed and asked to identify species they think are present at the FUSJ. Published data were reviewed to determine which species were expected to occur in San Julian. Two lists (amphibians and reptiles) totaling 97 species (including 95 expected, 38 found and 2 not expected) was generated. The quality and significance of our data is discussed.

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Tests were conducted that evaluated efficacy of wax matrix bait stations for Ceratitis capitata (Wiedemann) adults in Guatemala. Bait stations were exposed to outdoor conditions to determine effect of weathering on longevity as indicated by bait station age. Results of laboratory tests found that bait stations with spinosad and ammonium acetate remained effective for at least 31 d compared with pesticide-free controls, although there was some loss of efficacy over time. Percentage mortality for bait station strips with 2% spinosad and 1% ammonium acetate decreased from 100 +/- 0.0% on day 0 to 70 +/- 7.1% after 31 d. Ammonia concentration had little effect on percentage mortality although there was some indication that ammonia concentration affected number of flies observed on the bait stations. Bait station strips (one per cage) were more effective than controls for 6-8 wk when tests were conducted in field cages (3 m diameter x 2 m), but only 2-3 wk when tests were conducted in large (2.5 m high and 6.0 m wide and 7.5 m long) field cages. Longevity was restored when multiple bait stations (3, 6, or 12) were deployed per cage. Bait stations containing methomyl were used for field tests of efficacy for wild flies. Dipped lure bait stations, which were made by coating two edges of commercial ammonium acetate and trimethylamine lures, killed six times more flies than corn cob bait stations dipped into a Nulure/malathion solution. They also killed more flies than pesticide-free controls for 8 wk.

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Theraphosid tarantulas, like all other spiders, secrete silk from spigots on the abdominal spinnerets. A few years ago, it was proposed that the large tarantula Aphonopelma seemanni could extrude silk from specialized spigots on the tarsi to help adhesion to vertical surfaces. This suggestion was later questioned because silk was not observed after the spinnerets had been sealed. Recently, experiments with the tarantula Grammostola rosea again suggested tarsal silk secretion. All observations of the supposed tarsal silk were made in spiders with functional spinnerets, thus contamination with silk coming from the spinnerets could not be excluded. Recent morphological arguments also questioned putative tarsal spigots and proposed that they are actually contact chemoreceptors. We here test the supposed tarsal silk secretion in Aphonopelma seemanni, Avicularia avicularia, Brachypelma vagans and Grammostola mollicoma using similar experimental conditions as the previous authors, but with sealed spinnerets. Our results clearly demonstrate that when spinnerets are sealed, tarantulas do not show any tarsal silk secretion. We reinterpret those putative tarsal spigots and discuss possible evolutionary implications of these findings.

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Contamination routes of Listeria monocytogenes were examined for 3 years in an Iberian pork-processing plant that produced high-quality ready-to-eat meat products. Molecular subtypes of L. monocytogenes were determined by polymerase chain reaction-based serotyping and pulsed-field gel electrophoresis (PFGE) restriction analysis. A total of 541 L. monocytogenes isolates were recovered from the environment and equipment (n = 165), carcasses (n = 28), raw products (n = 321), and dry-cured products (n = 27). Only 29 different PFGE types were identified, 3 of which were repeatedly found to be persistent types and accounted for 73% of the isolates. One PFGE type dominated (45% of the isolates) and was mostly recovered from intermediate manufactured products and the environment of the manufacturing area. L. monocytogenes persistence appeared strongly linked to the manufacture of products and not to its sustained entrance with the raw material. Some clones were found to survive in the manufacturing area for 3 years. Controlling the contamination of raw ingredients, improving the compartmentalization, and changing the cleaning protocols resulted in reduced prevalence rates of L. monocytogenes on products; two persistent PFGE types were eliminated from the processing plant, although eradication of other adapted strains has not been achieved.

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As with all spiders, tarantulas spin silk from specialized structures in the abdomen called spinnerets, which are key features unique to the group. Recently Gorb et al. reported that the zebra tarantula Aphonopelma seemanni also secretes silk from its feet, which might improve its ability to climb on vertical surfaces. Here we show that when the spinnerets are experimentally sealed, the zebra tarantula cannot secrete silk or similar threads, disagreeing with previous reports by Gorb et al.. Additional evidence also disagrees with leg secretion of silk.

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The environment and products from an Iberian pig abattoir and processing plant were sampled to investigate the prevalence and genetic diversity of Listeria monocytogenes. The organism was not detected in the pig carcasses prior to processing. Fresh and dry-cured pork did show detectable levels, always ranging below 100CFU per gram. A total of 163 L. monocytogenes isolates collected during one year were characterized by PCR-based serotyping and pulsed-field gel electrophoresis (PFGE) restriction analysis. Three predominant PFGE types or pulsotypes seemed to persist in the plant. The pulsotype S1 (serotype group 1/2a, 53% of the isolates) was mostly recovered from whole pieces of meat and environmental sites, while pulsotypes S2 (1/2a, 17%) and S4 (1/2b, 21%) were more frequently associated with ground pork products. The pulsotype S4 was also found in a grinding machine, suggesting a possible association of this machine with the contamination of the ground meat products.