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The objective of this study was to evaluate the efficacy of monepantel and levamisole on gastrointestinal helminths in sheep herds in western Santa Catarina. The study was done in two stages. In the first one, five farms were selected and three groups (K, L and M) of 8 sheep each were formed. In the animals of group K, Monepantel (2.5 mg/kg) was administered, in those of group L, Levamisole (5.0 mg/kg) and the animals of group M were used as control (not medicated). The samples of feces were collected on day 0 and 10 of experiment, analyzed by the technique of McMaster with the objective of determining the number of eggs per gram of feces (HPG), followed by the technique of stool for the identification of the parasites. The second stage of the study was developed in a farm, where the same three groups were formed previously described with their respective treatments, and five days after the antiparasitic administration, feces sampling of these Animals for the performance of ecotoxicological tests, using Springtails (Folsomia candida) as a biological marker. To simulate the use of sheep feces as organic fertilizer, we define the doses 0; 2 4 and 8 tons of feces per hectare, as well as the survival and reproduction tests according to the ISO methodologies. The animals that received the treatment with Monepantel had reduction of the parasitic load (P < 0.05) compared with the remaining groups. In only one farm, the reduction of HPG was inferior (P < 0.05) in animals treated with levamisole compared to the control group. In the groups treated with Monepantel, resistance of Trichostrongylus spp was observed. At the same, and Haemonchus spp. It was resistant to levamisole on most farms. The efficacy of Monepantel for the five farms was 97, 98, 99, 100 and 100%, respectively, unlike the Levamisole, where they found efficiencies of 69,25, 52, 90 and 50%. The ecotoxicological tests show that there was no difference in the survival and reproduction of the collectors between the groups, ie the feces of animals medicated with levamisole and Monepantel does not affect F. candida. Therefore, the Monepantel, a relatively new antiparasitic product in the Brazilian market, can be the effective alternative in sheep farms with serious problems of resistance to anthelmintics, since it had desired efficacy in all the analyzed farms. [ABSTRACT FROM AUTHOR]

Pontoscolex corethrurus is the most widespread earthworm species in tropical and sub-tropical zones and one of the most studied in soil science. Although, ecological interactions of P. corethrurus with its environment are well documented, the taxonomic status of the species remains unclear. In this study, we investigated phylogenetic relationships within the genus Pontoscolex , in particular focusing on morphologically indistinguishable (i.e., cryptic) lineages. A total of 792 specimens collected from 25 different countries and islands all over the world were analyzed using two mitochondrial (COI and 16S rDNA) and two nuclear (internal transcribed spacers 2 and 28S rDNA) markers, and a total of 11 morphological characters both internal and external were investigated in all genetically characterized lineages. A large-scale multilocus sequence data matrix was also obtained for Pontoscolex spp. specimens using the Anchored Hybrid Enrichment (AHE) method. Multilocus phylogenetic and phylogenomic analyses, combined with species delimitation methods; including single locus (mPTP, ABGD) and multilocus (BPP) approaches, revealed congruent results. Four cryptic species were supported within the P. corethrurus species complex, and four potentially new species within the genus Pontoscolex . One widespread lineage (L1), within P. corethrurus complex was observed in the current population of Fritz Müller’s garden where P. corethrurus was first described in 1856. Cryptic lineages were observed in sympatry at several localities. This, in combination with observed heteroplasmy in COI gene in one population raises an important question of reproductive isolation between these species. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the insecticidal and repellent effects of tea tree, Melaleuca alternifolia (Myrtales: Myrtaceae), and andiroba, Carapa guianensis (Sapindales: Meliaceae), essential oils on two species of fly. For in vitro studies, free-living adult flies were captured and reared in the laboratory. To evaluate the insecticidal effects of the oils, adult flies of Haematobia irritans (L.) and Musca domestica L. (both: Diptera: Muscidae) were separated by species in test cages (n=10 per group), and subsequently tested with oils at concentrations of 1.0% and 5.0% using a negative control to validate the test. Both oils showed insecticidal activity. Tea tree oil at a concentration of 5.0% was able to kill M. domestica with 100.0% efficacy after 12 h of exposure. However, the effectiveness of andiroba oil at a concentration of 5.0% was only 67.0%. The insecticidal efficacy (100.0%) of both oils against H. irritans was observed at both concentrations for up to 4 h. The repellency effects of the oils at concentrations of 5.0% were tested in vivo on Holstein cows naturally infested by H. irritans. Both oils demonstrated repellency at 24 h, when the numbers of flies on cows treated with tea tree and andiroba oil were 61.6% and 57.7%, respectively, lower than the number of flies on control animals. It is possible to conclude that these essential oils have insecticidal and repellent effects against the species of fly used in this study. [ABSTRACT FROM AUTHOR]

Abstract: There are only some very small undisturbed forest fragments still remaining in the state São Paulo, Brazil, and loss of biodiversity and soil functions has been generalized. The few studies undertaken on this subject did not include any microbiological survey and interactions between microbiological and physical–chemical attributes to assist in understanding the development of this system. Therefore, the objective of this study was to identify microbiological indicators of soil quality that vary with seasonality and physical and chemical characteristics or along a time gradient of four areas—undisturbed forest (NT) and 20 (R20), 10 (R10), and 5 year-old (R05) recovering reforested areas—in two seasons (austral summer and winter). All analyzed soils had a high bulk density, due to mechanization during the course of sugar cane plantation. Lower soil bulk density values were found at NT (1.33gcm−3) and R20 (1.37gcm−3 Macroporosity at NT (0.21m3 m−3) was about twice as high than at R20 and R10, and four times higher than at R05. Also, total carbon (TC) and total N (TN) were twice as high at NT in both seasons. NO3–N contents varied according to season and recovery age, being greatest at the NT site and about three times higher in summer. Microbial biomass of carbon (MBC) and urease varied consistently with recovery age, independently of eventual differences in soil physical attributes. Dehydrogenase, in the winter, was most influenced by soil texture. Attributes as humidity and microporosity had a negative influence on dehydrogenase activity and on MBN. Soil bulk density was negatively correlated with the microbial biomass and urease activity. On the other hand, macroporosity had a positive effect on CO2–C evolution, microbial biomass of nitrogen (MBN) and acid phosphatase activity. There was a higher correlation between microbiological attributes, especially between MBC, MBN, and urease or dehydrogenase activity. T-RFLP showed greater similarity of the Bacteria community between NT and R20, only in the summer. We expect that these findings can help to understand and interpret oncoming studies and will be applicable to other systems focusing on the comparison of sites with differences in recovery age or soil chemical and physical attributes. [Copyright &y& Elsevier]