ABSTRACT. The thermophilic bacteria of Campylobacter spp. It Constitutes pathogens frequently identified in cases of diarrhea in humans. A locally non-existent evidence of published works of Campylobacter spp. In laying hens. The objective of this investigation was to determine the presence of Campylobacter spp. And resistance profile of strains isolated from laying hens, located in the poultry division of the Faculty of Veterinary Sciences of the National University of Asunción. A total of 150 cloacal swab specimens were collected from laying hens of the Hisex Brown line. The samples were submitted to microbiological analysis and species identification based on morphological and biochemical characteristics. The antimicrobial resistance to Ciprofloxacin and Erythromycin, was performed using antibiotic gradient strips method by agar diffusion. Of the 22 samples were positive to Campylobacter spp, jejuni species, representing a presence of 15%. Results of antimicrobial resistance demonstrated that strains of Campylobacter jejuni showed 95% resistance to Ciprofloxacin. No resistance to Erythromycin was observed. A low prevalence of Campylobacter spp. In laying hens However, the high resistance observed to Ciprofloxacin should serve as a basis for the correct antimicrobial activity in the poultry production chain.

RESUMEN. Las bacterias termófilas de Campylobacter spp. constituyen los patógenos frecuentemente identificadas en casos de diarrea en humanos. A nivel local no existe evidencia de trabajos publicados sobre las mismas en gallinas ponedoras. El objetivo del estudio fue determinar la presencia de Campylobacter spp. y perfil de resistencia de cepas aisladas en gallinas ponedoras, localizadas en la División de Avicultura de la Facultad de Ciencias Veterinarias de la Universidad Nacional de Asunción. Se analizaron 150 muestras de hisopado cloacal de gallinas ponedoras de la línea Hisex Brown. Fueron sometidas a análisis microbiológicos e identificación de especies en base a características morfológicas y bioquímicas. La resistencia antimicrobiana a la Ciprofloxacina y Eritromicina fue realizada utilizando método de tiras con gradiente de antibióticos por difusión en agar. Del total de muestras 22, fueron positivas a Campylobacter spp, especie jejuni, representando una presencia del 15%. Los resultados de resistencia antimicrobiana demostraron que las cepas de Campylobacter jejuni presentaron 95% de resistencia a la Ciprofloxacina, no observándose resistencia a la Eritromicina. Se observó una baja presencia de Campylobacter spp. en gallinas ponedoras sin embargo, la alta resistencia observada a la Ciprofloxacina, debería servir de base para el manejo de los antimicrobianos en la cadena productiva avícola.

The lethal and sublethal effects of the ecdysone agonist methoxyfenozide on the fall armyworm, Spodoptera frugiperda (J. E. Smith), were investigated by feeding a methoxyfenozide-treated diet to fifth instars until pupation in doses corresponding to the LC10 and LC25 for the compound. Larval mortality reached 8% and 26% in the low and high concentration groups, respectively, on the seventh day of the experiment. A progressive larval mortality of 12% for the LC10 and 60% for the LC25 was observed before pupation. Treated larvae exhibited lower pupal weights, higher pupal mortality, presence of deformed pupae, and more deformed adults than untreated larvae. The incorporation of methoxyfenozide into the diet had a significant effect on the timing of larval development. The development period for males and females was about seven days longer than the controls for both concentrations tested. In contrast, the compound affected neither pupae nor adult longevity. Finally, S. frugiperda adults that resulted from fifth instars treated with methoxyfenozide were not affected in their mean cumulative number of eggs laid per female (fecundity), nor percentages of eggs hatched (fertility), or the sex ratio. Our results suggest that the combination of lethal and sublethal effects of methoxyfenozide may have important implications for the population dynamics of the fall armyworm.