Warbler Research Articles

First reported case of Hypoderma diana Brauer, 1985 (Diptera: Oestridae)‐associated myiasis in a horse in Germany

SummaryA massive infestation with warble fly larvae was observed in a mare in Lower Saxony, Germany. From a herd of 20 horses, only a single mare accidently escaped the routine treatment with macrocyclic lactone in autumn and showed the myiasis infestation next year in January. Eighteen subcutaneous nodules were found on the back (n = 2), ribs (n = 3), flank (n = 5) and croup (n = 8). Deer, the specific hosts of the warble fly Hypoderma diana, was abundant on this farm and some other risk factors for the hypodermiosis are discussed herein. This is the first report of myiasis caused by H. diana in horses in Germany. This massive warble fly infestation in a horse in Germany reported here is important to alert equine health professionals concerning the prevention of this disease in the routine parasite control programme.

Human myiasis caused by the reindeer warble fly, Hypoderma tarandi, case series from Norway, 2011 to 2016.

Hypoderma tarandi causes myiasis in reindeer and caribou (Rangifer tarandus spp.) in most northern hemisphere regions where these animals live. We report a series of 39 human myiasis cases caused by H. tarandi in Norway from 2011 to 2016. Thirty-two were residents of Finnmark, the northernmost county of Norway, one a visitor to Finnmark, and six lived in other counties of Norway where reindeer live. Clinical manifestations involved migratory dermal swellings of the face and head, enlargement of regional lymph nodes, and periorbital oedema, with or without eosinophilia. Most cases of human myiasis are seen in tropical and subtropical countries, and in tourists returning from such areas. Our findings demonstrate that myiasis caused by H. tarandi is more common than previously thought. Healthcare professionals in regions where there is a likelihood of human infestation with H. tarandi (regions populated by reindeer), or treating returning travellers, should be aware of the condition. All clinicians are advised to obtain a detailed travel history when assessing patients with migratory dermal swellings. On clinical suspicion, ivermectin should be given to prevent larval invasion of the eye (ophthalmomyiasis). Since H. tarandi oviposits on hair, we suggest wearing a hat as a prevention measure.

The mystery of the missing warbler.

The mystery of the missing warbler.

Anotaciones sobre una curiosa oviposición de la mosca del tórsalo en condiciones experimentales (Diptera: Cuterebridae)

A partir de 9 ejemplares de D. hominis (L. Jr.), nacidas en el labo­ratorio, se observó interesante oviposición posiblemente originada por una única hembra: tres posturas fueron hechas sobre un pedazo de vegetal seco con un total de 96 huevos; por lo menos dos posturas más en el abdomen y cabeza de una Dermatobia macho con 74 huevos en total, y 8 huevos más en el abdomen de otra Dermatobia hembra. Se hace un comentario sobre la posibilidad de transmisión del tórsalo a partir de huevos eventualmente depositados por el cuterébrido sobre objetos fijos.

Molecular Characterization of Hypoderma SPP. in Domestic Ruminants from Turkey and Pakistan.

The aim of this study was to determine the morphological and molecular characterization of Hypoderma spp. in cattle and yak from provinces in Turkey and Pakistan. In total, 78 Hypoderma larvae were collected from slaughtered animals in Turkey and Pakistan from October 2015 to January 2016. Thirty-eight of these 78 Hypoderma larvae were morphologically classified as third instar larvae (L3s) of Hypoderma bovis, 37 were classified as Hypoderma lineatum, and 3 were classified as suspected or unidentified. The restriction enzyme TaqI was used to differentiate the Hypoderma spp. by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP). According to the sequences and the PCR-RFLP results, all larval samples from cattle from Turkey were classified as H. bovis, except for 1 sample classified as H. lineatum. All Hypoderma larvae from Pakistan were classified as H. lineatum from cattle and as Hypoderma sinense from yak. This study provides the first molecular characterization of H. lineatum (cattle) and H. sinense (yak) in Pakistan based on PCR-RFLP and sequencing results.

Distribution and Taxonomic Status of the Dusky Warbler Gerygone tenebrosa

Data on distribution, status and ecology are given for Gerygone tenebrosa, G. rnagnirostris and G. levigaster, all of which inhabit mangroves in northern Western Australia. G. tenebrosa is shown to be a distinct species, differing from magnirostris strongly in behaviour and morphology.

Treatment and control of bovine hypodermosis with ivermectin long-acting injection (IVOMEC® GOLD).

BackgroundThe studies reported here were conducted to assess the efficacy of ivermectin long-acting injection (IVM LAI; IVOMEC® GOLD, Merial; 3.15 % w/v ivermectin) for the treatment and control of natural infestations of cattle by Hypoderma bovis and Hypoderma lineatum, which are the most economically important oestrid flies of cattle in the northern hemisphere.MethodsCattle selected from herds with a history of Hypoderma infestation were grouped into blocks of three (Italy, 33 cattle; Germany, 30 cattle) or two (USA, 16 cattle) animals each, on the basis of positivity at the pre-treatment anti-Hypoderma antibody titres. Within each block, animals were randomly allocated to one of the following treatment regimens: saline (control); IVM LAI, administered at the predicted time of occurrence of first-instar larvae (Italy, Germany, USA); IVM LAI, administered at the predicted time of occurrence of second- and/or third-instar larvae (Italy, Germany). All treatments were administered by subcutaneous injection in correspondence of the area anterior to the shoulder at 1 ml/50 kg body weight, which corresponds to 630 mcg IVM/kg for IVM LAI.ResultsNo Hypoderma larvae emerged from animals treated with IVM LAI, whereas live H. lineatum (Italy) or H. bovis (Germany, USA) larvae were collected from saline-treated animals (P < 0.01). No adverse reactions to treatments were in any of the animals enrolled in the study.ConclusionsThe results from this study demonstrate that ivermectin in a long-acting formulation is 100 % efficacious in the treatment of cattle naturally infested by H. bovis and H. lineatum larvae at all stages of development. IVM LAI can, therefore, be used as ‘prophylactic’ treatment for Hypoderma spp. infestations in absence of external evidence of their presence and thus prior to skin and carcass damage, and as ‘therapeutic’ treatment, when warbles are already present.

Изучение сезонной динамики и сроков развития ларвальных фаз возбудителей гиподерматоза крупного рогатого скота в Чеченской Республике

Objective of research: to study the regional epizootology, species composition and bioecological features of development of causative agents of cattle hypodermatosis and elaboration of struggle measures against it in the Chechen Republic.&#x0D; Materials and methods: Data on extensity and intensity of invasion, species composition of causative agents of cattle hypodermatosis, seasonal dynamics, larval approach to the surface of animal back (gadfly larvae deposited in animals’ skin), time of the larval-pupal transformation (stages of larval development), treatment and prevention measures are provided in this article.&#x0D; Results and discussion: This research has found that in the Chechen Republic the extensity of gadfly invasion was in the range 24,4% — 62,1%; the intensity of invasion was 9,8 — 24,0 larv./animal. Two gadfly species Hypoderma bovis De Geer and Hypoderma lineatum De Villers are causative agents of animal hypodermatosis.&#x0D; H. bovis is spread everywhere, H. lineatum — mainly in plain and piedmont of the republic. Gadfly flight in different natural-climatic zones of the republic is registered from the end of April until the middle of October.&#x0D; Treatment and prevention measures continuously conducted for the whole livestock ( in spring against larvae of the 1st stage and in autumn — against larvae of the 2nd and 3rd development stages), taking into account ecological, phenological and epizootological situation in the region, may contribute to the full elimination of causative agents of hypodermatosis or their significant minimizing, reduction of economic damage to livestock of the republic.&#x0D; Based on experimental data, the economically reasonable schedule of treatment and prevention measures has been created.

Modulatory effects of interferon-γ and interleukin-4 on cellular immune responses against Hypoderma lineatum antigens.

This study investigates the in vitro modulatory effects of interferon-γ (IFN-γ) and interleukin-4 (IL-4) on both proliferative bovine T cell responses and IL-10 production induced by different antigens [crude larval extract and the purified fractions hypodermin A, B and C (HyA, HyB, HyC)] obtained from first instars of Hypoderma lineatum (Diptera: Oestridae), alone or in the presence of the mitogen concanavalin A. Incubation with the different parasitic antigens resulted in significant inhibition of T cell proliferation and IL-10 production, which, in general, did not revert after the addition of IFN-γ and IL-4. In the absence of antigens, IL-4 induced significant inhibition of mitogen-induced T cell responses. Exogenous IFN-γ exhibited an inhibitory effect on cell proliferation in the presence of the purified fractions HyB and HyC. These in vitro data suggest that far from neutralizing the effects of larval antigens, the addition of IFN-γ potentiates their anti-proliferative activity; by contrast, IL-4 had no consistent effects on proliferative responses to Hypoderma. IL-4 provoked an increment of IL-10 levels in supernatants of HyB-stimulated cells. In conclusion, exogenous IFN-γ and IL-4 were unable to counteract the suppressor effects of H. lineatum antigens.

Variation in the intensity and prevalence of macroparasites in migratory caribou: a quasi-circumpolar study

Comparative studies across time and geographical regions are useful to improve our understanding of the health of wildlife populations. Our goal was to study parasitism in migratory caribou (Rangifer tarandus (L., 1758)) of North America and Greenland. A total of 1507 caribou were sampled across 12 herds to assess seven of their main helminth and arthropod macroparasites between 1978 and 2010. We sought to determine which factors such as sex, age class, herd size, and season best explained the prevalence and intensity of those parasites. Intensity of warble fly (Hypoderma tarandi (L., 1758)) larvae increased with age for males, whereas the opposite was observed in females. Prevalence of giant liver flukes (Fascioloides magna (Bassi, 1875) Ward, 1917), tapeworm Taenia hydatigena Pallas, 1766, and nose bot fly (Cephenemyia trompe (Modeer, 1786)) larvae was higher in adults than in calves. Prevalence of F. magna and T. hydatigena was higher at high herd size than at lower herd size. Greenland herds had the lowest prevalence of T. hydatigena and of the tapeworm Taenia krabbei Moniez, 1879, a higher intensity of H. tarandi, and a higher prevalence of C. trompe than the other herds. Of the herds from Quebec and Labrador, the Rivière-George herd had a higher prevalence of F. magna than the Rivière-aux-Feuilles herd. Our research provides the first comparative survey of these parasites of caribou across a broad spatial–temporal range.

Genetic diversity and population genetics of the warble flies Hypoderma bovis and H. sinense in Qinghai Province, China.

BackgroundHypoderma bovis and H. sinense (Diptera: Oestridae) mainly parasitise cattle and yaks. The two parasites are pathogenic and cause economic losses that result from reduced amounts of livestock products, including milk, meat, and skin. Genetic diversity and population genetic structure of H. bovis and H. sinense have not been evaluated, but could be used to inform appropriate strategies to control these parasites.MethodsWe cloned and sequenced part of the mitochondrial cytochrome c oxidase subunit I (COI) gene from 60 H. bovis isolates and 52 H. sinense isolates from five locations in Qinghai Province, China, to identify polymorphisms, and infer their phylogenetic relationships, historical population expansions, and divergence time.ResultsWe identified 17 COI haplotypes from the H. bovis samples, and 23 COI haplotypes from the H. sinense samples. The haplotype and nucleotide diversities were 0.738 and 0.00202 for H. bovis, and 0.867 and 0.00300 for H. sinense, respectively, which indicates rich genetic diversity in H. bovis and H. sinense populations. Bayesian phylogenetic analysis revealed that the two species are monophyletic, and geographical structuring of haplotypes was significantly different in H. sinense (P < 0.05), but not H. bovis. Neutrality tests and mismatch distribution statistical analysis revealed that populations of the two species have undergone demographic expansions. The divergence three Hypoderma spp. (H. bovis, H. lineatum, and H. sinense) was estimated to have occurred approximately 4.5 million years ago (Mya), which indicates that the rapid uplift of the Qinghai-Tibetan Plateau during the late Miocene-Pliocene was associated with divergence of Hypoderma species.ConclusionsResults of the present study revealed that both H. bovis and H. sinense displayed high genetic diversity and widespread population genetic differentiation within and among populations; these data, along with the molecular phylogeny, demographic history, and divergence time estimation, provide new insight into evolutionary history of these species. These findings will help elucidate speciation in Hypoderma and provide theoretical basis for epidemiological surveillance and control of these species on the Qinghai-Tibetan Plateau.

Hypodermosis in Northern Serbia (Vojvodina)

Abstract This paper describes the first documented case of cattle grub (hypodermosis) in Northern Serbia (Vojvodina). Subcutaneous warbles were determined in a si x year old Simmental cow, at nine places along the spine. After the extirpation of larvae, based on the morphological characterisation, larvae of the third stage of Hypoderma bovis were diagnosed. The cow was administered therapeutic treatment, which had a favorable outcome, with no signs of recurrence. To the authors’ best knowledge, the case described in this paper is the first documented case of hypodermosis in cattle in Northern Serbia (Vojvodina). As the climate changed in the past few decades, it is important to pursue detailed investigations of the prevalence of this parasitic myiasis, as there are few such literature data for the Southern region of Serbia. One should also not ignore the fact that species of the genus Hypoderma can cause myiasis in humans as well.

Prevalence of hypodermosis in cattle slaughtered in industrial slaughtered-house of Ardebil, Iran.

Hypodermosis is one of the important veterinary problems because of its worldwide prevalence and significant economic losses. Economic losses is due to decreasing of productivity potential and leather quality. The disease is caused by two parasitic fly species in cattle, Hypoderma bovis and lineatus. Diagnosis of the parasites has crucial importance because of treatment and eradication plannings. Basically diagnosis is based on parasitological methods but recently serological methods were used in some countries. In the present study, a total of 3716 cattle were investigated in Industrial Slaughter house of Ardebil, Northwest of Iran. In this study, the prevalence of H. lineatus and H. bovis was 0.32% (12 larva) and 1.07% (40 larva), respectively. Low prevalence of hypodermosis could be caused by cold climate of studied region also shows efficacy of controlling programs. Unlike low prevalence of Hypoderma spp. in the studied regions, antiparasitic agents such as organophosphates and avermectins should be used to reduce the prevalence.

Seasonality of goat warble fly infection by Przhevalskiana silenus (Diptera, Oestridae) in Italy

Among factors that negatively impact on livestock, parasite infections represent a serious challenge to the health, welfare, productivity and reproduction of goats. In Mediterranean countries for example larvae of Przhevalskiana silenus (Diptera, Oestridae) cause a myiasis known as goat warble fly infestation that may induce significant economic losses to goat productions. In this study carcasses of 580 goats (551 females and 29 males) from 48 farms, regularly slaughtered in southern Italy, were examined for P. silenus presence across two years (from January 2011 to December 2012). For each carcass, the skin and subcutaneous tissues were examined for larvae of P. silenus and, when retrieved, specimens were counted and classified according to their developmental stage. Overall, P. silenus larvae were detected in 42 (87.5%) out of 48 farms and in 285 (49.1%) out of 580 goats. The number of larvae ranged from 1 to 38 per infested goat, with a mean of 5.2 larvae (±4.8). A total of 1209 larvae were retrieved of which 385 were identified as first stage (L1), and 394 and 430 as second (L2) and third (L3) stage, respectively. The prevalence rate of infestation was significantly higher in younger goats compared to older (p=0.0298). Dynamic of larvae in inspected animals showed different patterns being higher in August, November and March for L1, L2 and L3, respectively.Results of this study showed that P. silenus infection is widespread among farms of the study area. Nevertheless, as it occurs in other Mediterranean countries, P. silenus infection is still an overlooked infestation in Italy and more awareness on this infection and adequate control strategies are advocated.

Hypodermin A, a potential agent for prevention of allogeneic acute rejection

Immunosuppressive agents play an important role in the success of organ transplantation, however the chronic toxicity of these agents is a major issue over the long-term. Hypodermin A (HA) is an enzyme secreted by the larvae of Hypoderma lineatum (Diptera: Oestridae), and has been implicated in immunosuppression in cattle. Malassagne et al. have demonstrated that HA can degrade the C3 protein, and could be used to prevent hyperacute xenogeneic rejection. We found that overexpression of HA in RAW264.7 cells induced significant secretion of prostaglandin E2 (PGE2), which mediates a variety of innate and adaptive immune responses through four E-type prostanoid (EP) receptor subtypes (EP1–4). PGE2 is useful in the management of allogeneic acute rejection. In addition, we found that induction of PGE2 expression downregulates the expression of interferon (IFN)-γ and interleukin (IL)-2, and promotes the secretion of IL-10 in vitro through the EP4 receptor. It was previously shown that activation of IL-2 and IFN-γ is involved in allograft acute rejection. IL-10 is known to prevent inflammation, and can improve allograft survival rates. We concluded that besides preventing hyperacute xenogeneic rejection, HA might also be a potential therapeutic candidate for ameliorating acute rejection during allotransplantation.

Risk mapping of bovine hypodermosis using geographical information system (GIS) in cattle of subtropical region, Pakistan.

Hypodermosis is an ectoparasitic disease of cattle caused by Hypoderma lineatum and Hypoderma bovis. It is an important health problem of cattle, leading to considerable economic losses. There are various factors that are involved in the spread of this disease such as herd size, location, temperature, humidity, and precipitation. Blood samples from 112 herds were collected to determine the presence of Hypoderma spp. infestation. For these herds, size and location were determined; temperature, humidity, and precipitation data were obtained from meteorological stations; and topographic features were obtained from existing maps and through field work. A regression analysis was then used to generate a risk factor analysis profile for hypodermosis and geographic information system (GIS) was used to map the risks. The GIS map developed showed the degree of infestation in different geographical locations at district and village levels. Cluster analysis demonstrated that hypodermosis prevalence varied within zones and across zones. The regression analysis showed that the temperature in the months of January, February, March, August, and November, and the precipitation in September and October had significant results (p < 0.05) when all the risks factors were analyzed. It is concluded that different ecological factors have an important impact on the intensity and infestation rate of hypodermosis across the globe. The present study might be used to control and eradicate the hypodermosis across the globe.

Scanning electron microscopy of antennal sensory organs of the cattle grub, Hypoderma lineatum (Diptera: Oestridae).

Hypoderma lineatum (Villers, 1789) (Diptera: Oestridae) is a hypodermosis fly that has resulted in great economic losses worldwide. The antennae of cattle grub males andfemaleswere examined through stereoscopic microscopy and scanning electron microscopy to reveal the general morphology, combined with distribution, type, size, and ultrastructure of the antennal sensilla. All of the three antennal segments (antennal scape, pedicel, and funiculus) possess microtrichiae on their surface. Mechanoreceptors only exist on the antennal scape and pedicel. The antennal funiculus presents four types of antennal sensilla: trichoid, basiconic, coeloconic, and clavate sensilla. Three distinctive characters of H. lineatum are obvious: (1) the relatively slender, flexible, and equal-height mechanoreceptors; (2) the enlarged antennal pedicel, and numerous antennal sensory pits and pit sensilla on the antennal funiculus; and (3) all types of antennal sensilla clustered in sensory pits, respectively. Additionally, the enlarged antennal pedicel and abundant sensory pits and pit sensilla might facilitate odor detection, enhance olfactory sensitivity and accuracy, and also protect the fragile antennal sensilla from mechanical irritation or damage.

In warblers, longer migration means drabber females

In warblers, longer migration means drabber females

Plasma kinetics, excretion in milk of eprinomectin, and its efficacy against Hypoderma spp. following topical administration in yaks.

The plasma pharmacokinetics and mammary excretion of eprinomectin weredetermined in dairy yaks following topical administration at a dose of 0.5mg/kg. The kinetics of plasma and milk concentrations were analyzed using a noncompartmental model. Plasma and milk concentrations of eprinomectin increased to reach maximal concentrations of 5.45±2.84 and 2.29±0.90ng/mL at a Tmax of 1.79±0.57 and 2.00±0.82days, respectively. The concentration of eprinomectin in plasma was remained >0.5ng/mL for more than 30days after administration. The mean residence times of eprinomectin in plasma and milk were 14.73±6.22 and 9.37±2.81days, respectively. The AUC value in plasma (55.89±18.16ng day/mL) was threefold greater than that in milk (18.02±6.48ng day/mL). The AUC milk/plasma ratio was 0.33±0.08. The systemic availability of eprinomectin in yaks was lower than that observed value in other domestic bovines. The low level of eprinomectin excretion in milk suggests that eprinomectin can be used in yaks with zero milk-withdrawal time. The efficacy of eprinomectin against naturally acquired larvae of Hypoderma spp. was also determined in yaks. Topically administrated eprinomectin at a dose of 0.5mg/kg was 100% efficacious against larvae of Hypoderma bovis, H.lineatum, and H.sinense.

First records of Little Rush Warbler for Benin

First records of Little Rush Warbler for Benin