Chemical composition and effect of essential oils of Thymus vulgaris and Origanum vulgare on adults and ovigerous masses of Pseudosuccinea columella

Fasciolosis is a worldwide distribution zoonosis that causes great damage in ruminant breeding and has the aquatic mollusc Pseudosuccinea columella as an intermediate host. Synthetic molluscicides are the most used for control; however, they are harmful to fauna and flora. Therefore, this study aimed to evaluate the effect of essential oils from Thymus vulgaris, Origanum vulgare, and terpene carvacrol, on adult molluscs and eggs of P. columella. Analysis of EO volatile components was carried out on a gas chromatograph equipment coupled with mass spectrometry selective detector. The studied components were diluted in concentrations of 10, 20, 40, 60, 80 and 100 ppm, and it was observed that O. vulgare at concentrations of 60, 80 and 100 ppm, carvacrol at the concentrations of 80 and 100 ppm, and T. vulgaris at a concentration of 80 ppm led to 100% mortality of molluscs. All concentrations the substances tested showed 100% ovicidal activity.

Gaseous ozone and ozonized mist in the control of Escherichia coli on 'Rama Forte' persimmon

This study aimed to evaluate the effectiveness of using two ozone applications (gaseous and mist) as a disinfection method for fresh persimmon. To test these sanitizers, in vitro and in vivo assays were performed, and the Escherichia coli was selected because it is a pathogen that causes foodborne diseases in humans. For in vitro experiments, a plate was inoculated with Escherichia coli strain ATCC 25922 and treated. For in vivo assays, persimmon fruit surface was inoculated with the bacteria and treated. For both assays, it was used 10,15,20,30,40 and 50 μL L-1 of gaseous ozone or ozonized mist for five minutes. The results demonstrated that the gas ozone application significantly reduced the growth of E. coli on the plate surface in vitro at doses of 30, 40 and 50 μL L-1 (with 0.83, 0.89 and 0.95 log CFU mL-1, respectively). The application of ozonized mist showed a significant reduction for 50 μL L-1 (with 1.28 log CFU g-1). And, for the in vivo assays, ozonized mist significantly reduced the number of bacteria on the persimmon surface, with a 1.57 log reduction, which was the largest for 40 μL L-1. Therefore, it is possible to conclude that the ozone application can contribute to the control of microorganisms present on fruit surfaces.

Reducing anthelmintic inputs in organic farming: Are small ruminant farmers integrating alternative strategies to control gastrointestinal nematodes?

To counter the global spread of anthelmintic resistance (AR), considerable efforts have been invested in the development and dissemination of sustainable alternatives to control gastrointestinal nematode (GIN) infections in small ruminants. The degree to which these have been accepted and integrated by farmers, particularly in organic systems, where the drive to reduce chemical inputs is arguably even more pressing, has been little studied. To identify whether more comprehensive actions are needed to support the uptake of alternative GIN controls amongst organic farmers, this study conducted a survey in five European countries on organic dairy goat and meat sheep farmers to gain insight into current GIN control strategies and farmer attitudes towards AR and alternative measures in these countries. The structured survey was disseminated in the five European countries Switzerland, France, Netherlands, Lithuania and United Kingdom, receiving a total of 425 responses, 106 from organic dairy goat farmers and 319 from organic meat sheep farmers. Regression analyses were carried out to identify factors impacting anthelmintic drenching on meat sheep production systems, whereas all data were analysed descriptively. Four key findings emerged: i) The frequency of anthelmintic treatments averaged less than two per animal a year in all production systems; ii) Overall, organic farmers seemed well informed on the availability of alternative GIN control methods, but fewer stated to put them into practice; iii) Targeted selective treatment (TST) strategies of anthelmintics appears to be not commonly incorporated by organic farmers; iv) Despite operating under national and EU organic regulations, each of the organic dairy goat (Switzerland, France and Netherlands) and meat sheep (Switzerland, Lithuania and United Kingdom) production systems developed distinct approaches for GIN control. To increase uptake of alternatives to GIN control and optimise anthelmintic use, initiatives that promote research dissemination, farmer participatory and knowledge transfer activities at national level would be desirable.

Recent advances and future perspective of essential oils in control Colletotrichum spp.: A sustainable alternative in postharvest treatment of fruits

The world population growth has raised concerns about food security. Agricultural systems are asked to satisfy a growing demand for food with increasingly limited resources, and simultaneously still must reduce the impacts on the environment. This scenario encourages the search for safe and sustainable production strategies. Reducing losses in the production process can be one of the main ways to guarantee food safety. In fruticulture, it is estimated that more than 50% of the production can be lost between harvest and the final consumer due to postharvest diseases caused by phytopathogenic fungi. The fungi of the genus Colletotrichum are opportunistic and are associated with several diseases, being the anthracnose the most relevant in terms of the quality and yield losses in fruit species around worldwide. To control these diseases, the use of synthetic fungicides has been the main instrument utilized, however, because of their phytotoxicity to human health, the environment, and strong selection pressure imposed by continuous applications, the fungicides have caused resistance in the pathogen populations. So reducing the excessive application of these products is indispensable for human health and for sustainable Agriculture. Towards this purpose, research has been carried out to identify the phytopathological potentiality of essential oils (EOs) extracted from plants. Therefore, this review aims to contribute to the formation of knowledge bases, about the discoveries, recent advances, and the use of EOs as a strategy to alternatively control fungal disease caused by Colletotrichum spp. in postharvest fruits. Here, we provide valuable information exploring the application potential of essential oils as commercially useful biorational pesticides for food preservation, contributing to sustainable production and global food security.

A journey through 50 years of research relevant to the control of gastrointestinal nematodes in ruminant livestock and thoughts on future directions

This review article provides an historical perspective on some of the major research advances of relevance to ruminant livestock gastrointestinal nematode control over the last 50 years. Over this period, gastrointestinal nematode control has been dominated by the use of broad-spectrum anthelmintic drugs. Whilst this has provided unprecedented levels of successful control for many years, this approach has been gradually breaking down for more than two decades and is increasingly unsustainable which is due, at least in part, to the emergence of anthelmintic drug resistance and a number of other factors discussed in this article. We first cover the remarkable success story of the discovery and development of broad-spectrum anthelmintic drugs, the changing face of anthelmintic drug discovery research and the emergence of anthelmintic resistance. This is followed by a review of some of the major advances in the increasingly important area of non-pharmaceutical gastrointestinal nematode control including immunology and vaccine development, epidemiological modelling and some of the alternative control strategies such as breeding for host resistance, refugia-based methods and biological control. The last 50 years have witnessed remarkable innovation and success in research aiming to improve ruminant livestock gastrointestinal nematode control, particularly given the relatively small size of the research community and limited funding. In spite of this, the growing global demand for livestock products, together with the need to maximise production efficiencies, reduce environmental impacts and safeguard animal welfare - as well as specific challenges such as anthelmintic drug resistance and climate change- mean that gastrointestinal nematode researchers will need to be as innovative in the next 50 years as in the last.

Xanthosoma sagittifolium is resistant to Meloidogyne spp. and controls Meloidogyne enterolobii by soil biofumigation

Meloidogyne is a relevant plant-parasitic nematode that causes enormous damage. It is very challenging to control, and there are not many chemicals available on the market for that. As an alternative method of nematode control, biofumigation is increasingly gaining space. This research aimed to study the reaction of Xanthosoma sagittifolium to Meloidogyne enterolobii, M. incognita, and M. javanica and soil biofumigation with X. sagittifolium leaves for M. enterolobii control. The reaction test was performed in the populations 0 (control), 333, 999, 3,000, 9,000, 27,000 eggs and eventual juveniles. X. sagittifolium did not host the Meloidogyne species studied, even in a high population. X. sagittifolium leaves incorporated in soil at concentrations 0 (control), 0.45, 0.9, 1.8, 3.6 g were also studied to control M. enterolobii, and they were able to reduce galls and eggs. The number of galls and egg masses was reduced to a concentration of 1.8 g. In the maximum concentration, the number of galls was less than 15 galls, and the eggs were also reduced to less than 200 eggs. As these macerates emitted nematicidal volatile organic compounds (VOCs) against M. enterolobii, it reduced the infectivity and reproduction of nematodes.

1,8-cineole and castor oil in sodium lauryl ether sulphate disrupt reproduction and ovarian tissue of Rhipicephalus (Boophilus) microplus

Essential and fixed oils have been researched as alternatives to chemical acaricides. The activity of volatile compounds from essential oils (1,8-cineole, citral and eugenol) at 1.0% (w/v) and fixed oil (castor oil) at 0.3% (w/v) dissolved in 2.0% (v/v) dimethyl sulfoxide (DMSO) + 0.2% (w/v) Tween 80^® was assessed against Rhipicephalus microplus using immersion tests. 1,8-cineole (29.0%) and castor oil (30.2%) had the highest reproductive inhibition rate. A second experiment was performed to verify the effect of the 1,8-cineole (10.0% w/v) and, or castor oil (0.3% w/v) on tick reproduction using different solubilizing agents. The highest reproductive inhibition was observed for the combination of 1,8-cineole/castor oil (94.1%) and 1,8-cineole in 2.0% (w/v) sodium lauryl ether sulphate (SLES) (92.8%). A third experiment showed morphological changes in R. microplus oocytes at different stages of development, as well as in pedicel cells. The most intense effects were observed when ticks were immersed in the formulation containing 1,8-cineole (10.0% w/v) and castor oil (0.3% w/v) dissolved in 2% (w/v) SLES. These findings highlight the potential of this formulation as an alternative for managing cattle ticks as their cytotoxic effects can reduce R. microplus reproductive success.

Association of mechanical cleaning and a liquid preparation of diatomaceous earth in the management of poultry red mite, Dermanyssus gallinae (Mesostigmata: Dermanyssidae)

The poultry red mite (PRM), Dermanyssus gallinae, is an ectoparasite of great importance related to poultry farms worldwide. Problems associated with its control have led to the search for alternative treatments, especially using inert dust, which has recently been introduced into liquid formulations. Therefore, the objective of this work was to evaluate the acaricidal activity of a liquid diatomaceous earth (DE) preparation in the laboratory and its association with mechanical cleaning (brushing) in the field. In the laboratory it was first determined that a concentration of 10% DE would be necessary for field applications. The field experiment was conducted in a commercial poultry house. The 10% DE liquid preparation was administered in three applications and associated to mechanical cleaning. Then, 42 days after the first DE application, a population reduction of 94.7% was observed in relation to the initial population of mites. These results confirm the efficiency of DE applications in association with mechanical cleaning already adopted in poultry houses as an alternative for the control of D. gallinae, which can also contribute to avoiding mite resistance to chemical acaricides.

Efficacy of plants extracts from the Cerrado against adult female of Dermacentor nitens (Acari: Ixodidae)

Dermacentor nitens tick is commonly found in the equine auditory canal, where it causes economic losses due to its direct damage, causing blood spoliation, stress, transmission of pathogens, and predisposition to myasis and secondary bacterial infection in its hosts. In this study we evaluated the effect of ethanolic extracts of Cerrado plants on biological parameters of engorged females of D. nitens. Ethanolic extracts were prepared from the leaves of Schinopsis brasiliensis, Piptadenia viridiflora, Ximenia americana, and Serjania lethalis at 25-150 mg mL^-1. Groups of 10 engorged adult females were treated with these extracts and compared with a control containing distilled water and another control with organophosphate, using five replicates for each group. Compared with the control with water, S. lethalis and X. americana extracts at 100 and 150 mg mL^-1 significantly inhibited the posture ability. Differently, extracts of S. brasiliensis and P. viridiflora were the most effective in inhibiting larval hatching. Extracts of X. americana and P. viridiflora showed effective inhibition of reproductive parameters of the tick, presenting dose-dependent effect with IC₉₀ 78.86 and 78.94 mg mL^-1, respectively. Theses effective extracts contained low condensed tannin levels and their HPLC chromatograms revealed the presence of flavonoids. The efficacies of P. viridiflora and X. americana extracts were higher than 90% indicating that these extracts are promising as alternative agents for D. nitens control.

First report of the effect of Ocotea elegans essential oil on Rhipicephalus (Boophilus) microplus

Rhipicephalus (Boophilus) microplus is responsible for reducing animal welfare, causing a drop in productive performance and transmitting hemoparasites. The main strategy of tick control is application of synthetic acaricides. However, parasite resistance to these compounds is a major concern. Therefore, the acaricidal and repellent in vitro effect of the Ocotea elegans essential oil on larvae and adult females of R. (B.) microplus were evaluated. The larval packet test (LPT), larval repellency test (RT) and adult immersion test (AIT) were performed. The essential oil was analyzed by gas chromatography (GC/FID) and the structure of the oil's major constituent (92.2% sesquirosefuran) was elucidated by nuclear magnetic resonance. In the AIT, efficacy higher than 90% was detected from the concentration 25 mg/mL upward. In both LPTs performed after 48 h, only the 100 mg/mL concentration resulted in mortalities above 70%. On the other hand, the essential oil caused an average of 95.8% repellency from 0.78 to 100 mg/mL. The LC₅₀ in the two LPT (48 h) tests were 59.68 and 25.59 mg/mL, respectively. The LC₅₀ and LC₉₀ in the AIT were 4.96 and 17.37 mg/mL, and in the RT they were 0.04 and 1.24 mg/mL respectively. We conclude that the essential oil of O. elegans leaves has a significant acaricidal effect on engorged females and on larval repellency of R. (B.) microplus ticks, and can be a promising alternative for the control of this ectoparasite.

Control of Haemonchus contortus in sheep using basidiocarps of Agaricus blazei Murril

OBJECTIVE

This study evaluated the effects in vitro and in vivo of Agaricus blazei against Haemonchus contortus in sheep.

METHODS

The in vitro efficacy of aqueous extract on egg hatching inhibition (EHI) was investigated and after 72 h incubation with varying concentrations the effects on, blastomeres, embryonated eggs, and first stage larvae (L1) were evaluated. Larval development inhibition (LDI) for dry powder and the aqueous extract were evaluated in fecal cultures of sheep infected with H. contortus. In vivo efficacy was determined by reduction in fecal egg count (FEC). Lambs were treated with powder A. blazei (11.4 g/kg pc) or trichlorfon, or were untreated and the possible toxicity of this fungus was monitored by plasmatic enzyme analysis.

RESULTS

Concentrations equal to and higher than 3.62 mg/mL and of aqueous extract were 100% effective in the EHI test. In the LDI test, LC90 was estimated for 5.66 and 106.0 mg/g fecal culture for aqueous extract and powder, respectively. The mean FEC in lambs 14 days post-treatment with A. blazei powder was significantly lower than observed for the negative control, and the serum levels of aspartate transaminase and alanine transaminase were normal.

CONCLUSION

The fungi supplementation promotes, respectively, high and moderate anthelmintic efficacy with in vitro and in vivo tests, respectively, suggesting it as an alternative or complementary treatment for haemonchosis in sheep.

Effects of the protective, curative, and eradicative applications of chitosan against Penicillium expansum in apples

Apple is one of the most important temperate fruit to Brazil economy, and the use of synthetic chemicals has been the main method for reducing postharvest diseases, such as the blue mold, caused by Penicillium expansum. This work intends to evaluate the practical utilization of chitosan for blue mold control. For this purpose, fruits were treated in a preventive and curative way, immersing the fruits in chitosan solution (5 or 10 mg mL⁻¹), or adding a single drop of this solution (10 mg mL⁻¹) directly into the injuries. The eradicative effect of the polysaccharide was also evaluated in vitro and in vivo. Chitosan did not show a curative effect against the blue mold, and its eradicative effect was only evidenced on the higher concentration (10 mg mL⁻¹). On the other hand, preventively, without the addition of adjuvants, chitosan reduced blue mold incidence in fruits by 24% and 93%, through the immersion or the single drop methods, respectively. Thus, it was found that, for long scale utilization, some improvements in the physico-chemical properties of the chitosan are needed, since it was only capable to prevent the infection by P. expansum when directly added on the fruit injury.

Acaricidal properties of vetiver essential oil from Chrysopogon zizanioides (Poaceae) against the tick species Amblyomma cajennense and Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)

Ticks are arthropods widely distributed in tropical and subtropical regions, which can transmit infectious agents also responsible for zoonoses. Excessive use of conventional acaricides has resulted in the onset of drug resistance by these parasites, thus the need to use alternative methods for their control. This study evaluated the acaricidal activities of Chrysopogon zizanioides (vetiver) essential oils containing different zizanoic and khuzimol (high and low acidity) acid concentrations on Amblyomma cajennense and Rhipicephalus microplus (Acari: Ixodidae). To this aims, toxicity tests of different concentrations of examined essential oils were conducted on adult females and larval stages. Results showed that the essential oils of C. zizanioides with high and low acidity reduced oviposition of females, eggs hatch and larval survival, being more effective than some commercial products widely used to control these ectoparasites. These results indicate that the C. zizanoides essential oils are promising candidates as acaricidal agents and represent also an add value to vetiver oil with high acidity, which is commercially undervalued in the cosmetic industry.