Larval Counts Research Articles

Effect of linex treatment on IFN-γ and IL-4 in mice infected with Trichinella

Trichinellosis is a zoonotic, foodborne parasitic infection causing muscle damage. This study investigated the potential therapeutic effects of the commercially available probiotic treatment Linex, both alone and in combination with Albendazole (ALB), on the intestinal and muscular stages of Trichinella spiralis infection in mice, assessing outcomes through parasitological, immunological, and histopathological measures. This study is the first to demonstrate the synergistic effect of combining the commercially available probiotic Linex with Albendazole for trichinellosis treatment. By enhancing both parasitological and immunological outcomes, this combined therapy not only significantly reduces parasite burden but also modulates the immune response, shifting it toward a protective Th1 profile. In parasitological terms, the highest adult and larval count reduction was observed in combined Linex and Albendazole treatment (100%, 97.7%) respectively. Lesser percentage of reduction were recorded in Linex alone therapy (43.2%, 88.4%) respectively. Histopathologically there was amelioration of the inflammatory cellular infiltration in all treated groups with best results in combined Linex and Albendazole treatment. Immunologically, serum IFN-γ levels increased significantly in all treated groups with highest levels in combined Linex and Albendazole treatment, while IL-4 and IL-13 level decreased significantly in all treated groups with best results observed in Linex alone treatment. To conclude; combined Linex and Albendazole treatment of mice infected with T. spirals could ameliorate the infection and improve the immune response.

Increase in dairy production of goats with subclinical nematode infection using injectable eprinomectin

The effect of the treatment with an injectable product containing eprinomectin on milk yield, milk composition, and somatic cell count (SCC) was investigated in naturally infected dairy goats with low gastrointestinal nematode faecal egg and pulmonary larval counts. The study involved 394 lactating goats and was conducted on a farm in southern Spain. Before treatment, faeces from all animals were analysed to establish two homogeneous groups according to the gastrointestinal nematode egg counts (185 treated and 209 untreated). On day 0, each goat in the treatment group received a single subcutaneous injection of 12 mg of eprinomectin (0.6 ml of Eprecis®, CEVA, Spain). The control goats were left untreated. Faecal egg counts and coprocultures were performed on days 0, 30, 60, and 90 post-treatment. Milk samples were taken on days 0, 30, 60, 90, and 120 and analysed to determine individual production and milk composition parameters, including fat (F), protein (P), lactose (L), total dry extract (TDE), and SCC. Examination of faecal samples indicated that the goats were mainly infected with gastrointestinal strongylids of the genera Teladorsagia and Trichostrongylus and Muellerius lungworms. The percentage reduction of gastrointestinal nematode faecal egg counts on days 30, 60, and 90 was 97.55 % (90 % CI = 95.1 % - 99.9 %), 90.65 % (90 % CI = 83.7 % - 97.6 %) and 87.5 % (90 % CI = 79.5 % - 95.5 %), respectively, and that of lung larval counts in faeces was 98.48 % (90 % CI = 96.3 % - 100 %), 96.91 % (90 % CI = 84.2 % - 98.9 %), and 82.05 % (90 % CI = 66.9 % - 97.2 %), respectively. Milk yield was consistently and significantly higher in the treated group than in the control group (p = 0.004). The treated goats showed a 4 % increase in daily milk yield (60 ml/day) compared with the untreated goats. There was a significant decrease in F and TDE in the treated goats compared with the untreated goats, but eprinomectin did not affect P, L, and SCC. The estimated economic benefit of using injectable eprinomectin was around 6.46€ per goat over the 120-day period. In conclusion, treatment with injectable eprinomectin has an economical positive effect on milk yield in goats, even those infected with a low burden of gastrointestinal and pulmonary nematodes.

Field Demonstration of Indigenous Strains Bacillus thuringiensis and Beauveria bassiana for Sustainable Management of Spodoptera litura in Groundnut

This study by Krishi Vigyan Kendra, Nellore, evaluates the efficacy of biopesticides Bacillus thuringiensis (Bt) and Beauveria bassiana formulations against S. litura compared to conventional insecticides over two growing seasons (2018-19 and 2019-20). Twenty Front Line Demonstrations (FLDs) involving 20 farmers were conducted, with treatments applied when leaf damage exceeded 25%. Results indicated significant reductions in leaf damage (8.40% for biopesticides vs. 8.89% for insecticides) and larval populations. Specifically, larval counts decreased substantially after treatment, with average counts at 50 DAS dropping from 21.29 (FP) to 3.37 (Demo) in 2018-19 and from 22.15 (FP) to 3.53 (Demo) in 2019-20. Economic analysis revealed comparable net returns and benefit-cost ratios for both treatments (1.92 and 1.93 for biopesticides and insecticides, respectively). These findings support the economic viability of adopting biopesticide, promoting sustainable agricultural practices and profitability in groundnut cultivation.

Damage and insecticidal control of stem borer (Busseola fusca L; Lepidoptera: Noctuidae) on maize in Halhal Begoss

A maize stem borer (Busseola fusca L) control study was conducted in Halhal Begos with the objectives of assessing the damage caused by the pest and identifying the simple method of control. The treatments used were Furadan 1G, Carbaryl 85%WP, Cymbush 1G and control. The data collected were larval count, dead heart count, tunnel length, per cent infestation at 30 and 45 days after emergency. The larval count was taken from the border rows, and yield was taken from the central row at harvest. All agronomic data, like the date to the heading plant height etc were taken on time. The results of the study showed that all the pesticides used gave good control of the larvae. Furadan gave the highest yield benefit and monetary value compared to the check.

Assessment of the Incidence of Pigeon Pea Leaf Webber, Grapholita critica (Meyr.) and Roller, Caloptilia soyella (Van.) in Relation to Weather Variables in the Bundelkhand Region of Uttar Pradesh

Background: Pigeon pea (Cajanus cajan, Mayer) is the member of Asian Cajanus crop and also reffered as Tur and Arhar and commonly grown in Kharif session in Indian subcontinent.). In India, around 250 known species of insect pests have been identified to affect pigeon pea crops at different growth stages. The leaf webber and leaf roller are notable insect pests that pose a significant threat to pigeonpea, particularly during its vegetative stage. The leaf webber and leaf roller, among various insect pests, are notably visible and pose a threat to pigeonpea. These insects target the pigeonpea plant during its vegetative stage. Specifically, the leaf webber, identified as Grapholita (Pammene) critica, Meyrick (Lepidoptera: Tortricidae), has been acknowledged as a significant constraint affecting pigeonpea production. The aim of this investigation is to assess the relationship between the incidence of leaf roller and leaf webber and various abiotic factors, including temperature, relative humidity, wind velocity and rainfall. Methods: The research, spanning Kharif 2021-22 and 2022-23, at Entomological Research Block in BUAT, Banda. It aimed to observe leaf roller and leaf webber incidence in pigeon pea alongside weather conditions. ‘IPA-203’ pigeon pea variety was manually sown in 200 m2 plots on July 12, 2021 (first year) and July 18, 2022 (second year). Standard agronomic practices were adhered to and no insecticides were used on the crop. Result: Over the two-year observation period, the larval population of G. critica on pigeon pea plants commenced during the 34th SMW, peaking at 4.90 larvae plant-1 in the 45th SMW. Simultaneously, C. soyella infestation initiated in the 34th SMW, steadily increasing until the 42nd SMW, reaching its peak larval count at 3.03.

Seasonal Occurrence of Fall Armyworm (Spodoptera frugiperda J.E. Smith) in Maize: The Role of Sowing Dates

Fall armyworm is a destructive insect pest in maize farming and has expanded widely throughout various agroecological zones, which threatens food security. An experiment was carried out at the Winter Nursery (ICAR-IIMR, Hyderabad) field to study the occurrence of fall armyworm on maize single cross hybrid DHM 117 across different sowing dates during kharif and rabi seasons of 2021-22. Weekly observations were made on a whole-plot basis to record the number of plants damaged, the number of larvae, and egg masses per plant. Among the six sowing dates, the crop sown on 2nd August 2021, had a relatively lower mean percent of infestation range (4.02% - 80.37%), a minimum larval count per plant range (0.01 - 0.24), and the least number of egg masses per plant range (0.00 - 0.11). The findings will be helpful in the construction of forecasting models, facilitating the formulation of eco-friendly management tactics to manage fall armyworms in maize.

Seasonal Incidence of Fall Army Worm <i>Spodoptera Frugiperda</i> (J E Smith) on Maize

Investigation on seasonal incidence of fall army worm Spodoptera frugiperda on maize was undertaken at the Department of Entomology, VNMKV, Parbhani. The studies were done during kharif on the maize variety Komal. Laval incidence was observed from 31st SMW (Standard Meteorological Week) i.e. fifth week of July and to till 43rd SMW i.e. fourth week of October with a peak incidence observed (4.05 larvae/plant) during 39th SMW. Thereafter larval count showed declining trend (1.9 larvae/plant) during 42nd SMW. Larval infestation also recorded in %age and under observation highest infestation 38.98% during 39th SMW i.e. fourth week of September. The correlation between larval incidence and weather parameters was showed negatively non-significant with minimum temperature, evening relative humidity and rainfall, whereas positive relationship was observed with maximum temperature and bright sunshine hours. The correlation with morning relative humidity evaporation with FAW population wee positively and negativity significant respectively evaporation was negative significant.

Organ-specific Toxocara canis larvae migration and host immune response in experimentally infected mice.

We investigated organ specific Toxocara canis larval migration in mice infected with T. canis larvae. We observed the worm burden and systemic immune responses. Three groups of BALB/c mice (n=5 each) were orally administered 1,000 T. canis 2nd stage larvae to induce larva migrans. Mice were sacrificed at 1, 3, and 5 weeks post-infection. Liver, lung, brain, and eye tissues were collected. Tissue from 2 mice per group was digested for larval count, while the remaining 3 mice underwent histological analysis. Blood hematology and serology were evaluated and compared to that in a control uninfected group (n=5) to assess the immune response. Cytokine levels in bronchoalveolar lavage (BAL) fluid were also analyzed. We found that, 1 week post-infection, the mean parasite load in the liver (72±7.1), brain (31±4.2), lungs (20±5.7), and eyes (2±0) peaked and stayed constant until the 3 weeks. By 5-week post-infection, the worm burden in the liver and lungs significantly decreased to 10±4.2 and 9±5.7, respectively, while they remained relatively stable in the brain and eyes (18±4.2 and 1±0, respectively). Interestingly, ocular larvae resided in all retinal layers, without notable inflammation in outer retina. Mice infected with T. canis exhibited elevated levels of neutrophils, monocytes, eosinophils, and immunoglobulin E. At 5 weeks post-infection, interleukin (IL)-5 and IL-13 levels were elevated in BAL fluid. Whereas IL-4, IL-10, IL-17, and interferon-γ levels in BAL fluid were similar to that in controls. Our findings demonstrate that a small portion of T. canis larvae migrate to the eyes and brain within the first week of infection. Minimal tissue inflammation was observed, probably due to increase of anti-inflammatory cytokines. This study contributes to our understanding of the histological and immunological responses to T. canis infection in mice, which may have implications to further understand human toxocariasis.

Validation of vacuum extraction protocol for larval sampling of spotted-wing drosophila in blueberries

For spotted-wing drosophila, Drosophila suzukii Matsumura, the standard larval sampling protocol from the fruits involves immersing the fruits in hot water, salt, or sugar solution followed by enumerating the larvae that exit from the fruit. In this study, using the fruit samples collected from commercial blueberry farms, we validated the efficacy of a novel D. suzukii larval sampling technique, the vacuum extraction protocol. The larval extraction efficacy of the vacuum extraction method was compared with the salt extraction method using paired fruit samples collected from three different fields for four consecutive weeks. Overall, larval counts detected through the vacuum extraction were significantly higher than those detected through salt extraction in two out of three blueberry fields. Additionally, among the five blueberry fruit sample volumes tested (118, 177, 237, 355, and 473 mL), we identified 355 mL (12 fl. oz.) as the optimum fruit sample volume for vacuum extraction that maximized sampling precision for unit sampling cost. Since D. suzukii larvae exited from fruits after vacuum extraction remain alive and active, a delay in separating the larvae from the sample with coffee filter extraction may result in larval movement back into the fruit flesh. However, compared with immediate processing, delaying coffee filter extraction up to 60 minutes after vacuum incubating the fruit samples at -98 kPa for 60 minutes did not significantly reduce the larval count. Overall, the results of validation trials indicate that vacuum extraction is a promising sampling method for growers to detect D. suzukii larval infestation in blueberries.

EPG and Pasture Larval Count of Gastrointestinal Nematodes are Strongly Influenced by Weather Parameters: Empirical Evidence from Parbhani Marathwada

Aims: the present study was aimed to develop a bioclimato of gastrointestinal nematodes of cattle in Marathwada region of Maharashtra. Study Design: A standard protocol as per published reports was followed for recording of prevalence of GI nematodes from cattle. Place and Duration of Study: The study was conducted at livestock instructional farm of College of Veterinary and Animal Sciences Parbhani during the period February 2022 to January, 2023. Methodology: In all total 253 faecal samples were collected from calves and adult cattle belonging to RK instructional farm, COVAS, Parbhani. Sample collection and processing was done by following standard parasitological procedures and only fresh fecal droppings were used for the laboratory investigation. Results: The study conducted on availability of larvae on pasture revealed the overall prevalence of 61 percent (87 pasture were positive out of 143 examined). The PLC analysis showed the highest distribution of larvae on pasture during winter season i.e. 57.81 %, followed by monsoon season i.e. 57.81 % and 00.0% during summer season. The Pasture larval count observed during different seasons was 23.83, 33.07 and 0.00 per 100 gm, respectively. The abstract information drawn from the bioclimatos plotted for 2000-2021 and its validation with real time data of 2022 ( Feb 2022-Jan 2023) was a) Suitable months for survival of Heamonchus and Oesophagostomum infective larvae on the pasture of the grazing land in year 2022-2023 were Jan - March and June – September and for Trichostrongylus Jan – March and October 2022- January 2023 and b)The climatic data and Bioclimato were plotted from year 2000-2021 and 2022+January 2023 showed the correlation between EPG and PLC. Conclusion: The bioclimatos can be developed and utilized according the regional agro-climatic variations and be useful for devising controlmeasures against gastrointestinal nematodes of livestock.

114 The efficacy of a natural fungus (Duddingtonia flagrans) in reducing gastrointestinal nematode indicators in lambs

Abstract Sustainable and profitable small ruminant production in the US is affected by infections with gastrointestinal nematodes (GIN), especially the blood sucking GIN, Haemonchus contortus. The overuse and misuse of available drug classes has led to multi-drug resistant GIN that pose significant challenges to parasite control on many farms. The objective of this study was to evaluate the effectiveness of a natural fungus (Duddingtonia flagrans; Bioworma, International Animal Health) in reducing GIN larval counts and other GIN indicators in hair sheep wethers. Eighteen St. Croix (n = 9) and Barbados Blackbelly (n = 9) wethers (227 ± 1.4 days of age and 29.7 ± 0.6 kg BW) were dewormed (d 0) with a combination of levamisol (Prohibit; 8 mg/kg BW) moxidectin (Cydectin; 0.2 mg/kg BW) and albendazole (Valbazen; 7.5 mg/kg BW) prior to the start of feeding according to the manufacturer’s recommendations for feeding BioWorma. At this time, lambs were separated into two treatment groups (n = 9/group), split into 3 replications per treatment group and placed on six pasture paddocks (0.06 ha; n = 3 per paddock) after accounting for breed, initial fecal egg count (FEC) and BW. Lambs were then fed daily either a grain supplement ration (corn and soybean meal) with Livamol with Bioworma (LIV) or without (CON) at 2% of their BW for 98 d. LIV was added to the ration based on total lamb BW/paddock. To evaluate the effect of LIV treatment, BW and body condition scores (BCS) were recorded every 2 wk for 98 d. Blood and fecal samples were also collected for determination of packed cell volume (PCV) and FEC. Pooled treatment group feces (d 0 – 98) were collected and cultured to determine GIN genera. A subset of animals/treatment (n = 3) will be harvested to determine abomasal worm counts. Data were analyzed using repeated measures in a mixed model, and FEC were log transformed before analysis. Following deworming (d 0), FEC were reduced by 100% by d 14. There was a mixed population of GIN at the start of the study (averaging 54%, 42%, 1.2% and 1.8% for H. contortus, Tricostrongylus spp., Oesphagostomum spp. and Nematodirus spp., respectively). LIV with Bioworma supplementation had no impact on BW, BCS, PCV or FEC in this study averaging 34.2 ± 0.3 kg, 2.5 ± 0.04, 34.7 ± 0.5% and 150.9 eggs per gram, respectively. Under the conditions of this study, Bioworma® supplementation had no influence on GIN indicators measured up to 100 d of grazing. This research will be continued during subsequent grazing seasons to determine the effect of continued supplementation on lamb parasite load and performance as well as pasture infestation levels.

Appraisal of Chitosan-Coated Lipid Nano-Combination with Miltefosine and Albendazole in the Treatment of Murine Trichinellosis: Experimental Study with Evaluation of Immunological and Immunohistochemical Parameters

PurposeResistance and adverse consequences of albendazole (ABZ) in treating trichinellosis urged demand for secure and effective new drugs. The current study aimed to assess the effect of chitosan-coated lipid nano-combination with albendazole and miltefosine (MFS) in treating experimental murine trichinellosis and evaluating pathological and immunological changes of trichinellosis.Materials and MethodsOne hundred twenty Swiss albino mice were divided into six groups. Each group was subdivided into a and b subgroups based on the scarification time, which was 7- and 40-days post-infection (PI), respectively. The treatment efficacy was evaluated using parasitological, histopathological, serological (interleukin (IL)-12 and IL-4 serum levels), immunohistochemical (GATA3, glutathione peroxidase1 (GPX1) and caspase-3), and scanning electron microscopy (SEM) methods.ResultsThe most effective drug was nanostructured lipid carriers (NLCs) loaded with ABZ (G5), which showed the most significant reduction in adults and larval count (100% and 92.39%, respectively). The greatest amelioration in histopathological changes was reported in G4 treated with MFS. GATA3 and caspase-3 were significantly reduced in all treated groups. GPX1 was significantly increased in G6 treated with MFS + NLCs. The highest degenerative effects on adults and larvae by SEM were documented in G6.ConclusionLoading ABZ or MFS on chitosan-coated NLCs enhanced their efficacy against trichinellosis. Although ABZ was better than MFS, their combination should be considered as MFS caused a significant reduction in the intensity of infection. Furthermore, MFS showed anti-inflammatory (↓GATA3) and antiapoptotic effects (↓caspase-3), especially in the muscular phase. Also, when loaded with NLCS, it showed an antioxidant effect (↑GPX1).Graphical abstract

Food and time: dietary plasticity of different sources of a generalist insect herbivore.

Painted lady butterflies (Vanessa cardui L.,Nymphalidae) are generalist herbivores and serve as a model system across several fields of biology. While it has been demonstrated that V. cardui caterpillars can develop on different host plants, much of this work has been done on commercially sourced caterpillars, which could limit our understanding of wild V. cardui populations. In this study, we sought to explore possible differences in how commercial and wild V. cardui caterpillars may respond to feeding on different host plants, and subsequently, how their diet impacts immune response and survival. Here, we analyzed performance, survival, and immune response of wild and commercially sourced V. cardui caterpillars over several generations on diets that consisted of either 1 of 4 different host plant species or a mixed diet including all 4 species. Qualitatively, we observed that wild larvae had a better larval performance and hemocyte counts compared to the commercial larvae. The results demonstrate that both wild and commercially sourced caterpillars grew and survived best on the same diet treatments (mallow, narrowleaf plantain, and a mixed diet) during development across generations. Immune responses showed similar patterns across host plants between wild and commercial populations, with individuals showing lowered immune responses on dandelion and lupine and higher ones on mallow, plantain and the mixed diet; although the relative rankings on those 3 diets varied. Survival also demonstrated similar patterns, in that individuals reared on dandelion and lupine had the lowest survival.

Efficacy of Insecticides Against Tobacco Catterpillar <i>Spodoptera Litura</i> (F) and Gram Caterpillar <i>Helicoverpa Armigera</i> (HUBN) on Groundnut

A field experiment was carried out during kharif 2021 to evaluate the efficacy of some insecticides against Spodoptera litura (F) and Helicoverpa armigera (Hubn) on groundnut. Amongst these, chlorantraniliprole 18.5SC @ 30g a.i. ha-1 proved to be the most effective with least larval counts (0.93 and 1.00 plant-1, respectively) and efficacy (63.27 and 63.70%, respectively) against S. litura and H. armigera, respectively after two sprays. This was followed by cyantraniliprole 10OD @ 90g a.i. ha-1 and novaluron 5.25+ indoxacarb 4.5SC @ 39.38+ 33.77g a.i. ha-1 giving maximum groundnut yield (22.37 q ha-1) with 52% increase over untreated control. The evaluation of economics revealed that chlorantraniliprole 18.5SC gave the highest monetary return, net income (Rs. 55765.00) and cost: benefit ratio (1:6.80).

Two protocols using fluralaner for Rhipicephalus microplus strategic control on taurine cattle in a tropical region

BackgroundThe present study aimed to evaluate the effects of different treatment strategies using a new commercial formulation containing pour-on fluralaner on Rhipicephalus microplus infestation in cattle and in pastures in a tropical climate region where up to five generations of this tick species can occur per year.MethodsForty-five naturally infested cattle were divided into three experimental groups: T01, treated with fluralaner (2.5 mg/kg) pour-on every 42 days; T02, the cattle received the first treatment with fluralaner on Day 0 but the next treatment involved a weekly visual evaluation; T03, control, received palliative treatment with a spray formulation when the group mean was ≥ 30 ticks. Counts of female R. microplus were performed weekly until day 343, and larval counts on pasture were performed on Days 0, 30, and 60 and every 30 days until Day 330.ResultsUsing fluralaner, six applications were performed in Group T01, and four were performed in Group T02. In the control group (T03), it was necessary to perform eight palliative acaricide treatments with the spray formulation. The animals in T01 and T02 showed lower mean tick counts (p ≤ 0.05) than the control group (T03) on 28 and 27 of the 49 evaluated dates, respectively. In the paddock where the animals were kept as controls, the R. microplus larvae counts increased to 1458. In the paddocks where the animals were treated with fluralaner, the number was ≤ 19 per paddock during the study.ConclusionsThe different strategic treatment protocols performed with pour-on fluralaner (2.5 mg/kg) over a year in taurine cattle in a tropical region with a history of up to five annual generations of cattle ticks were effective, maintaining levels of R. microplus infestations in animals and in pastures close to zero in most of the study. Depending on the retreatment criterion adopted, the number of applications per year may be lower, resulting in a reduction in the mean cost of acaricide treatment per year and lower exposure of R. microplus populations to the active ingredient, resulting in lower resistance and selection pressure.Graphical

Physical and bio-control methodologies for integrated management of buffalo fly-Haematobia exigua (Diptera: Muscidae)

Haematobia exigua, the buffalo fly, is a common ectoparasite of buffaloes and cattle in India causing economic losses and underlines the necessity of effective control strategies against them. The present study was planned to evaluate larvicidal activity of few methods for physical and biological control for integarated management of Haematobia exigua flies. Out of four bacterial bio-control agents evaluated by in-vitro assay and Probit analysis, two bacteria i. e. Bacillus thuringiensis var israelensis and Bacillus thuringiensis var kurstaki showed excellent larvicidal activity against H. exigua with LC50 value of 134 and 135 mg per liter of water respectively. Whereas, other two bacteria i. e. Bacillus weihenstephanensis WSBC and KBAB4 failed to show desired larvicidal activity. It can be concluded that B ti and B tk have future as effective bacterial agents (BCAs) in the control and integrated management of buffalo and horn fly. An experiment was conducted in the laboratory and on field for judging the efficacy of a physical method of tightly covering dung pats with polythene sheet for control of larvae of H. exigua. The laboratory result showed only 14.73% larvae were survived and developed per 100 gm of the faeces in the pot covered with polythene sheet as against significantly higher number 78.33% in the control group. During field trial, average larval count from dung pits before the experiment was 86.33 per 250 gm of faeces and it has been significantly reduced to 11.80 after covered with polythene sheets for two weeks. It indicated that physical method of covering the dung pits works immensely and thus can be inducted in IPM program as one of the effective physical control alternatives.

Bio-Efficacy of Novel Insecticides and Biopesticides against Diamondback Moth, Plutella xylostella (Linn.)

The present investigation entitled ‘bio-efficacy of Novel insecticides and bio-pesticides against Diamondback moth, Plutella xylostella (Linn.) was carried out on the cabbage, variety ‘Golden Acre’ during Rabi, 2021-22 and 2022-23. At Crop Research Centre, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut (UP). The data were recorded on five randomly selected plants once in a standard week. Pooled data of both the year (2021 and 2022), After treatments, spinosad 2.50% SC at 600 ml ha-1 consistently showed the lowest larval count on days 3, 7, and 14, with 3.33, 2.17, 2.25 larvae per five plants followed by emamectin benzoate 5% SG at 200 g ha-1, diafenthiuron 50% WP at 600g ha-1, Bacillus thuringiensis var. kurstaki at 1000 g ha-1, Beauveria bassiana at 1500 ml ha-1 and Metarhizium anisopiliae at 2000 g ha-1, and nimbecidine 0.03% at 2500 ml-ha, respectively. The nimbecidine 0.03% at 2500 ml ha-1 recorded the lowest efficacy. Chemical and biological treatments varied significantly, while chemicals had similar efficacy, and biologicals were equally effective. Control plots had the highest larvae count.

The distribution of strongylid egg and lungworm (Dictyocaulus eckerti) larval counts in adult female farmed red deer (Cervus elaphus), and the implications for parasite control

Whilst healthy adult farmed red deer show little clinical indication of parasite infection, they may still be maintaining infection levels on the farm through low-level shedding of nematode eggs and lungworm larvae. This work was undertaken to establish the long-term distribution of parasite counts, to determine whether the higher counts seen in previous trials are repeatable across the same animals. All adult female red deer on a New Zealand North Island property were faecal sampled (n = 209), weighed, and body condition scored (BCS) on five sampling occasions from March – August 2021. Faecal samples were processed by modified Baermanns to recover, identify, and enumerate lungworm 1st stage larvae (FLC), and nematode faecal egg counts (FEC) were determined by mini-FLOTAC. Between animal variation for FEC was significant (p < 0.001); whilst many counts were low to zero, a few individuals were consistently shedding higher egg counts. Younger animals tended to have higher egg counts (p = 0.003), but there was no association between FEC and BCS (p = 0.22), and FEC and liveweight (p = 0.58). Modelling of the data indicated that 50% of the egg output resulted from 21% of the animals. Additionally, there was no significant association between the higher egg counts and the gastrointestinal nematode classification; ‘long tails’ (likely Oesophagostomum sp.) p = 0.76, and the Ostertagiinae complex p = 0.75. Lungworm counts tended to be very low (0 – 26 lpg); consistent with previous trials and literature in farmed adult deer. However, between animal differences were statistically significant (p < 0.001) indicating some animals were passing more larvae than others, and poorer conditioned animals (BCS 2.5) were significantly associated with higher larval count (p = 0.03). There was no relationship between larval count and age (p = 0.62) and larval count and liveweight (p = 0.22). Modelling indicates that 50% of pasture larval contamination was contributed by 15% of the animals. There was no correlation between nematode egg count and lungworm larvae count (p = 0.22). Adult deer may play an important role as a source of infection for young deer, therefore, an improved understanding of the distribution of infection is needed to improve parasite control.

Efficacy of artemether against toxocariasis in mice: parasitological and immunopathological changes in brain, liver, and lung

ABSTRACT Toxocariasis is a zoonosis that represents a serious threat to public health particularly in tropical and subtropical areas. Currently, albendazole, the most effective drug for treating visceral toxocariasis, shows moderate efficacy against the larvae in tissues and has some adverse effects. Artemether is an antiparasitic drug mainly used in the treatment of malaria and showed effectiveness against numerous helminthic infections. Besides, it possesses potent anti-inflammatory, antiapoptotic, antifibrotic, and neuroprotective properties. Thus, the study’s aim was to investigate artemether’s effects in comparison with albendazole on the therapeutic outcome of experimental toxocariasis. For this aim, 140 laboratory-bred mice were divided into four main groups: uninfected control, treatment control, albendazole-treated, and artemether-treated groups. The treatment regimens were started at the 15th dpi (early treatment), and at the 35th dpi (late treatment). The effectiveness of treatment was determined by brain larval count, histopathological, immunohistochemical, and biochemical examination. Artemether showed more effectiveness than albendazole in reducing brain larval counts, markers of brain injury including NF-κB, GFAP, and caspase-3, the diameter and number of hepatic granulomas, hepatic oxidative stress, hepatic IL-6, and TG2 mRNA, and pulmonary inflammation and fibrosis. The efficacy of artemether was the same when administered early or late in the infection. Finally, our findings illustrated that artemether might be a promising therapy for T. canis infection and it could be a good substitution for albendazole in toxocariasis treatment.

Effects of metformin on parasitological, pathological changes in the brain and liver and immunological aspects during visceral toxocariasis in mice

There are currently insufficient anthelmintic medications available for the treatment of toxocariasis. For instance, Albendazole (ABZ) is the preferred medication, but its effectiveness against tissue-dwelling parasites is limited. In addition, Metformin (MTF) is a widely used oral antidiabetic medication that is considered to be safe for treatment. This study aimed to investigate any potential effects of MTF, alone or in combination with ABZ, on mice infections caused by Toxocara canis (T. canis). The efficacy of the treatment was assessed in the acute and chronic phases of the infection by larval recovery and histopathological, immunohistochemical, and biochemical studies. The results showed that combined therapy significantly reduced larval counts in the liver, brain, and muscles and ameliorated hepatic and brain pathology. It reduced oxidative stress and TGF-β mRNA expression and increased FGF21 levels in the liver. It decreased TNF-α levels and MMP-9 expression in the brain. In addition, it increased serum levels of IL-12 and IFN-γ and decreased serum levels of IL-4 and IL-10. In the acute and chronic phases of the infection, the combined treatment was more effective than ABZ alone. In conclusion, this study highlights the potential role of MTF as an adjuvant in the treatment of experimental T. canis infection when administered with ABZ.