Biomedical subjects

D Otranto

Publications and source records attributed to D Otranto.

At least 37 records · Page 2Linked to original sources

PubMed2004

Cross-sectional survey of ticks (Acari: Ixodidae) in sheep from an area of the southern Italian Apennines.

A cross-sectional survey of ticks was conducted on 197 ovine farms with animals pasturing in an area (3971 km2) of the southern Italian Apennines. The farms were selected to be uniformly distributed throughout the study area using Geographical Information System (GIS). Ticks were collected from 309 (31.4%) out of the 985 sheep sampled, belonging to 92 (46.7%) out of the 197 farms included in the study. The following tick species were found (farm prevalence): Dermacentor marginatus (37.6%), Haemaphysalis punctata (29.4%), H. sulcata (2.5%), H. parva (2.0%). H. inermis (0.5%), Ixodes gibbosus (2.0%), I. ricinus (0.5%), Rhipicephalus sanguineus group (1.0%), and R. bursa (0.5%). A point distribution map (PDM) was drawn by GIS in order to display the distribution of each tick genus in the study area. The general trends of the PDM show that Dermacentor marginatus and Haemaphysalis spp. were widely and homogeneously spread throughout the study area, whereas Rhipicephalus spp. and Ixodes spp. were present only in a few concentrated zones of the study area in accordance to their biological and ecological characteristics.

Animals↗

PubMed2004

The epidemiology of canine and feline dermatophytoses in southern Italy.

A total of 424 animals (268 dogs and 156 cats) with skin lesions (alopecia and peripheral scaling) were examined from January 1999 to December 2002. Of the 424 samples examined, 99 (23.3%) yielded a positive culture and, in particular, 20.5% of the dog samples and 28.2% of the cat samples. Microsporum canis was the most common dermatophyte isolated from dogs and cats (77.7%), followed by geophilic dermatophyte species (M. gypseum, Trichophyton terrestre). Young dogs and cats, especially those younger than 1 year, showed a statistically significant higher prevalence of M. canis infection than older animals. No statistically significant association was found between infection and sex in cats, while male dogs were more affected by dermatophytes. Among breeds, Yorkshire terriers showed the highest positivity (50%) caused mainly by M. canis (46.6%), while no differences were noticed for cats. A significantly higher prevalence of positive samples was registered in summer and in autumn for cats. The presence of dermatophytes was not associated with itching. The diagnostic value of Wood's lamp fluorescence and microscopic examination proved to be scarce compared with fungal cultures as only 45.5% of the 77 samples that tested positive for M. canis at the cultural examination was positive under Wood's lamp florescence and 53.2% at microscopic examination.

Age Factors↗

PubMed2004

Association between phospholipase production by Malassezia pachydermatis and skin lesions.

An evaluation was made of the phospholipase activities of Malassezia pachydermatis strains isolated from healthy dogs versus those from dogs with dermatitis and otitis. A high percentage of strains of M. pachydermatis obtained from lesion sites (93.9%) produced phospholipase, compared to the strains obtained from healthy skin of the same dog with localized lesions (41.4%) and healthy dogs (10.6%).

Animals↗

PubMed2004

Rapid immunochromatographic test for serodiagnosis of canine leishmaniasis.

An rK39 immunochromatographic test and immunofluorescent-antibody test (IFAT) for serodiagnosis of canine leishmaniasis were evaluated. The two tests showed correlation for all but one of the sera obtained from 68 dogs confirmed as leishmaniasis cases and 40 dogs (22 healthy dogs and 18 dogs with other diseases) from areas where the disease is not endemic. Specificity was 100% for both tests, while sensitivity was 97% for the rapid test and 99% for IFAT.

Animals↗

PubMed2004

A third species of Hypoderma (Diptera: Oestridae) affecting cattle and yaks in China: molecular and morphological evidence.

Cattle and yak hypodermosis in China is caused by Hypoderma bovis and H. lineatum, with a prevalence reaching up to 98-100% of the animals and maximum intensities exceeding 400 warbles for each animal. A third species, H. sinense, is also considered by Chinese researchers to affect livestock. The molecular characterization of the most variable region of the mitochondrial cytochrome oxidase I gene and of the ribosomal 28S gene has been performed for the third-stage larvae collected from cattle and yaks in China and identified (on the basis of the spinulation on the ventral side of the 10th segment) as H. bovis, H. lineatum, and H. sinense. Amplicons were digested with the HinfI and BfaI restriction enzymes, which provided diagnostic profiles to simultaneously differentiate the 3 Hypoderma species. Third-stage larvae of H. sinense were also examined by scanning electron microscopy, which revealed proper morphological characteristics different from those of H. bovis and H. lineatum. The molecular and morphological evidence herein reported support the existence of a third species of Hypoderma affecting cattle and yaks in China, and the results provide new tools for unequivocal identification of this species and present key components for the evaluation of its endogenous cycle and pathogenicity in animals and humans.

Animals↗

PubMed2004

[Myiasis caused by Oestridae: serological and molecular diagnosis].

Myiasis-causing Oestridae (bot flies) infect several animal species world-wide, from palaearctic to subtropical/tropical areas. Oestrids affect livestock production causing abortion, reduced milk production, losses in weight and fertility, poor hide quality and an impairment of the host's immune system. In the last few years much research has been carried out on the immunology of these infestations, in order to acquire efficient and reliable diagnostic serological tools; the genome of the different species of Oestridae has been studied to further their molecular identification, taxonomy and phylogenesis. The immunodiagnostic methods for many myiasis causing Oestrids have proven to be a viable alternative to the clinical parasitological examination or the post-mortem examination. Numerous serological tests have been developed for the diagnosis of bovine hypodermosis caused by Hypoderma bovis and Hypoderma lineatum, and ELISAs using larval hypodermin C as the antigen are currently used on serum, individual and pooled milk samples to detect the presence of circulating anti-Hypoderma antibodies. In Italy the best period to sample the animals is November-January, since it is in this period that the antibody kinetics of the animals reaches a peak. Recently the efficacy of the ELISA test on pasteurized milk samples has been demonstrated, allowing the diagnosis of bovine hypodermosis also in areas where there is no information on the presence of the disease and the sampling of the animals is laborious. The cross-reactivity between Przhevalskiana silenus antigens and anti-Hypoderma antibodies led to assessing the usefulness of a simple and cost-effective ELISA for the diagnosis of goat warble fly infection. In particular, it has been demonstrated that infected goats display an antibody peak in November-December in blood and milk, thus making this period suitable for sampling. Although no extensive data is available on the immunology of sheep and goat oestrosis caused by Oestrus ovis, the efficacy of ELISA has been demonstrated by correlating serological results with clinical post-mortem examinations. No immunological techniques are currently used to diagnose gasterophilosis of equids and only one study reports the efficacy of ELISA for detecting anti-Gasterophilus antibodies in infected equids. Several studies have been conducted into the molecular characterization of the mitochondrial DNA (mtDNA)--in particular of the gene encoding for the cytochrome oxidase I (COI)--for many free-living and parasitic arthropods for diagnostic, taxonomic and phylogenetic purposes. As regards Oestridae causing myiasis, the first study features a PCR-RFLP assay of the most common Italian species (i.e. H. bovis, H. lineatum, Gasterophilus intestinalis, P. silenus, O. ovis), which showed clear genetic differences among the genera examined, but no inter-specific variation between the two species of Hypoderma considered. The molecular characterization of the most variable region of the COI gene (encoding for the region from E4 to the terminal COOH) was able to clearly differentiate H. bovis and H. lineatum. The E4-COOH region of the COI gene has been characterized for 18 oestrid species and from a taxonomical point of view, molecular data confirm the morphological classification, with the examined species divided into four subfamilies. New insights have also been gained on the molecular differentiation of the most common species of Hypoderma (i.e. H. bovis, H. lineatum, Hypoderma actaeon, Hypoderma diana and Hypoderma tarandi) and, in particular, the restriction enzyme BfaI, provides a diagnostic profile that can be used to simultaneously differentiate all the species examined. The characterization of the E4-COOH COI gene and the hypervariable region of the gene encoding for the ribosomal Isu revealed the identity of Hypoderma sinense as a new species, infecting cattle and yaks in China. Finally, the molecular analysis of the same mitochondrial and ribosomal regions showed that P. silenus, Przhevalskiana aegagri and Przhevalskiana crossii are morphotypes of the same species.

Animals↗

PubMed2004

[Ecology of Thelazia spp. in cattle and their vectors in Italy].

The genus Thelazia (Spirurida, Thelaziidae) includes a cosmopolitan group of eyeworm spirurids responsible for ocular infections in domestic and wild animals and transmitted by different species of muscids. Bovine thelaziosis is caused by Thelazia rhodesi Desmarest 1828, Thelazia gulosa Railliet & Henry 1910, and Thelazia skrjabini Erschow 1928, which occur in many countries; T. gulosa and T. skrjabini have been reported mainly in the New World, while T. rhodesi is particularly common in the Old World. In Italy, T. rhodesi was reported in southern regions a long time ago and, recently, T. gulosa and T. skrjabini have been identified in autochthonous cattle first in Apulia and then in Sardinia. Thirteen species of Musca are listed as intermediate hosts of eyeworms, but only Musca autumnalis and Musca larvipara have been demonstrated to act as vectors of Thelazia in the ex-URSS, North America, ex-Czechoslovakia and more recently in Sweden. In Italy, after the reports of T. gulosa and T. skrjabini in southern regions, the intermediate hosts of bovine eyeworms were initially only suspected as the predominant secretophagous Muscidae collected from the periocular region of cattle with thelaziosis were the face flies, M. autumnalis and M. larvipara, followed by Musca osiris, Musca tempestiva and Musca domestica. The well-known constraints in the identification of immature eyeworms to species by fly dissection and also the time-consuming techniques used constitute important obstacles to epidemiological field studies (i.e. vector identification and/or role, prevalence and pattern of infection in flies, etc.). Molecular studies have recently permitted to further investigations into this area. A PCR-RFLP analysis of the ribosomal ITS-1 sequence was developed to differentiate the 3 species of Thelazia (i.e. T. gulosa, T. rhodesi and T. skrjabini) found in Italy, then a molecular epidemiological survey has recently been carried out in field conditions throughout five seasons of fly activity and has identified the role of M. autumnalis, M. larvipara, M. osiris and M. domestica as vectors of T. gulosa and of M. autumnalis and M. larvipara of T. rhodesi. Moreover, M. osiris was described, for the first time, to act as a vector of T. gulosa and M. larvipara of T. gulosa and T. rhodesi. The mean prevalence in the fly population examined was found to be 2.86%. The molecular techniques have opened new perspectives for further research on the ecology and epidemiology not only of Thelazia in cattle but also of other autochthonous species of Thelazia which have been also recorded in Italy, such as Thelazia callipaeda, which is responsible for human and canid ocular infection and Thelazia lacrymalis, the horse eyeworm whose epidemiological molecular studies are in progress.

Animals↗

PubMed2003

Molecular epidemiological survey on the vectors of Thelazia gulosa, Thelazia rhodesi and Thelazia skrjabini (Spirurida: Thelaziidae).

A Polymerase Chain Reaction (PCR)- based assay developed for the specific identification of Thelazia gulosa, Thelazia rhodesi and Thelazia skrjabini (Nematoda, Spirurida), which cause bovine ocular thelaziosis, was evaluated for its usefulness in detecting the intermediate hosts and in estimating the infection prevalence of vectors in field conditions throughout 5 years (from 1997 to 2001). A total of 5190 flies were captured and identified as Musca larvipara, Musca osiris, Musca autumnalis, Musca tempestiva or Musca domestica. Genomic DNA was extracted from pools constituted by heads, thoraces, abdomens and wings of 10 flies of each species, and 2076 samples were subjected to a PCR assay to specifically detect the ribosomal ITS-1 sequence of bovine Thelazia. Amplicons were sequenced and subjected to digestion with CpoI restriction enzyme. M. autumnalis, M. larvipara, M. osiris and M. domestica species were shown to be PCR positive. T. gulosa was specifically detected by PCR in M. autumnalis, M. larvipara, M. osiris and M. domestica, whereas T. rhodesi is in M. autumnalis and M. larvipara. Of 27 positive samples, 23 were positive for T. gulosa and 4 for T. rhodesi, with a mean prevalence of 2.86% in the whole fly population collected. The highest mean prevalence values of infection were detected in M. autumnalis (4.46%) and M. larvipara (3.21%), and the former species was confirmed to be the vector of T. gulosa and T. rhodesi. This study is the first report of M. osiris as a vector of T. gulosa and M. larvipara as a vector of T. gulosa and T. rhodesi under natural conditions. The occurrence of Thelazia in fly populations in the Apulia region of Italy (in the 5 grazing seasons considered) indicates that cattle thelaziosis is enzootic in southern Italy. This molecular assay should be a useful epidemiological tool for assessing the role of different species of flies as intermediate hosts of thelaziae.

Animals↗

PubMed2003

Molecular characterization of the mitochondrial cytochrome oxidase I gene of Oestridae species causing obligate myiasis.

A 688-bp region of the mitochondrial cytochrome oxidase I gene was sequenced from larvae of 18 species of Oestridae causing obligate myiasis. Larvae belonged to the four Oestridae subfamilies (Cuterebrinae, Gasterophilinae, Hypodermatinae and Oestrinae), which are commonly found throughout the world. Analysis of both nucleotide and amino acid data was performed. Nucleotide sequences included 385 conserved sites and 303 variable sites; mean nucleotide variation between all species was 18.1% and variation within each subfamily ranged from 5.3% to 13.34%. Intraspecific pairwise divergences ranged from 0.14% to 1.59%, and interspecific variation ranged from 0.7% to 27%. Of the 229 amino acids, 76 were variable (60 of which were phylogenetically informative), with some highly conserved residues identified within each subfamily. Phylogenetic analysis showed a strong divergence among the four subfamilies, concordant with classical taxonomy based on morphological and biological features. This study provides the first molecular data set for myiasis-causing Oestridae species, providing an essential database for the molecular identification of these parasites and the assessment of phylogenetic relationships within family Oestridae.

Animals↗

PubMed2003

Species identification of Hypoderma affecting domestic and wild ruminants by morphological and molecular characterization.

Cuticular structures and the sequence of the cytochrome oxidase I gene were compared for Hypoderma bovis (Linnaeus), Hypoderma lineatum (De Villers), Hypoderma actaeon Brauer, Hypoderma diana Brauer and Hypoderma tarandi (Linnaeus) (Diptera, Oestridae). Third-stage larvae of each species were examined by scanning electron microscopy revealing differences among species in the pattern and morphology of spines on the cephalic and thoracic segments, by spine patterns on the tenth abdominal segment, and by morphology of the spiracular plates. The morphological approach was supported by the molecular characterization of the most variable region of the cytochrome oxidase I (COI) gene of these species, which was amplified by polymerase chain reaction and analysed. Amplicons were digested with the unique restriction enzyme, BfaI, providing diagnostic profiles able to simultaneously differentiate all Hypoderma species examined. These findings confirm the utility of morphological characters for differentiating the most common Hypoderma larvae and reconfirm the power of the COI gene for studying insect identification and systematics.

Animals↗

PubMed2003

Thelazia callipaeda (Spirurida, Thelaziidae) of carnivores and humans: morphological study by light and scanning electron microscopy.

Thelazia nematodes cause ocular infection in several mammals and are transmitted by dipteran flies. Thelazia callipaeda Railliet and Henry 1910 (Spirurida, Thelaziidae) is common in the Far East, where it causes eyeworm infection in carnivores and humans. In the past few years, it has also been reported in dogs, cats and foxes in Northern and Southern Italy. Although a great deal of work has been carried out in China and other Eastern countries, knowledge of the morphology of T. callipaeda is scanty. Eighty-three nematodes collected from the eyes of naturally infected dogs from the Basilicata region (southern Italy) were examined by light and scanning electron microscopy, and the most important features of the nematodes were described. The morphological characteristics useful for the identification of T. callipaeda are discussed.

Animals↗

PubMed2002

A review of dicrocoeliosis of ruminants including recent advances in the diagnosis and treatment.

Despite its widespread presence among grazing ruminants, dicrocoeliosis, also known as "small liver fluke" disease, is poorly known and often underestimated by researchers and practitioners in many countries. This is primarily due to the multiple parasitic infections which affect ruminant livestock and mask the pathology of dicrocoeliosis, to the difficulties in diagnosing it with coprological techniques and, finally, to the few effective drugs found. Furthermore, the biological cycle of Dicrocoelium, which requires a snail and an ant as intermediate hosts, and the high number of ecological and epidemiological variables affecting the disease make it difficult to set up experimental designs to study dicrocoeliosis. In the past 50 years, many aspects of this disease have been broadly investigated (aetiology, life cycle, diffusion, epidemiology, pathogenesis and immunology) but its diagnosis and treatment still remain moot issues. Dicrocoeliosis often remains clinically undetected and its diagnosis is mostly based on adult dicrocoelia recovered in the liver post mortem or on egg detected at coprological examination. The prophylaxis of the small liver fluke has been difficult and unsatisfactory to date due to the complexity of its biological life cycle and epidemiology. Many anti-helminthic drugs are practically ineffective against dicrocoeliosis if used at the dosage recommended against other gastrointestinal helminths and lungworms. The most important aspects of the aetiology, biological cycle, spread, epidemiology and pathogenesis of dicrocoeliosis are reviewed and the recent advances in the diagnosis and treatment are focused on.

Animals↗

PubMed2001

Screening of commercial milk samples using ELISA for immuno-epidemiological evidence of infection by the cattle grub (Diptera: Oestridae).

Pasteurised and ultra high temperature (UHT)-treated milk were tested over the period November 1997-February 1998 in order to evaluate the applicability of an hypodermosis ELISA test on commercial milk samples. Milk samples from six dairy companies were analysed and the development of anti-Hypoderma antibodies recorded for the period from September 1998 to June 1999. For one dairy (no. 3) bulk milk samples were also obtained from the tankers, transporting milk away from the farms, and analysed; the results were compared to the parasitological status of the cows whose milk had been collected on the farms. Out of 32 pasteurised samples tested, 23 were positive, exceeding the cut-off (22%), while 9 samples were negative. UHT milk was always negative. The antibody levels in milk samples from four of the six companies were highest during January and decreased gradually during February to May 1999. The bulk milk samples also had high antibody levels and 47.2% of milk producing cows had lesions of hypodermosis. It was concluded that testing commercial milk for antibodies is an efficient way of detecting the presence of hypodermosis in cattle, especially in those countries for which no data on this disease are available.

Animals↗

PubMed2001

Differentiation among three species of bovine Thelazia (Nematoda: Thelaziidae) by polymerase chain reaction-restriction fragment length polymorphism of the first internal transcribed spacer ITS-1 (rDNA).

Thelazia gulosa, Thelazia rhodesi and Thelazia skrjabini are nematodes transmitted by some species of Musca (Diptera: Muscidae) which cause ocular infestations in bovines. Differences in the rDNA of these species were determined by a PCR using different sets of relatively conserved oligonucleotide primers. PCR on the first internal transcribed spacer (ITS-1) revealed differences in size in Thelazia species (437 bp for T. gulosa, 370 bp for T. rhodesi and 506 bp for T. skrjabini) while the DNA control of Musca spp. was not amplified. The ITS-1 amplicons of the three species were sequenced and then analysed. The GC contents ranged from 26 to 36% and the level of differences in the nucleotide sequences of ITS-1 was lower between T. skrjabini and T. gulosa (39%) than the latter and T. rhodesi (49-56%). Restriction fragment length polymorphism (RFLP) of ITS-1 amplicons was also carried out and the restriction profiles compared. Clear genetic differences among the three Thelazia examined were demonstrated by using the enzymes HpaII, CpoI and SspI. This PCR-RFLP for the delineation of T. gulosa, T. rhodesi and T. skrjabini offers prospects as a molecular epidemiological tool to study parasite transmission patterns and prevalence.

Amino Acid Sequence↗

PubMed2001

The immunology of myiasis: parasite survival and host defense strategies.

Infestations by dipterous larvae that feed on dead or living vertebrate tissues for a variable period are known as myiases; these infestations reduce host physiological functions, destroy host tissues and cause significant economic losses to livestock worldwide. Recent advances in understanding the specific and nonspecific immune responses of hosts to infestation by myiasis-causing larvae and the immunological strategies evolved by larvae against the host are reviewed here. The practical implications of immunological knowledge for diagnostic and vaccination strategies are also discussed, with a view to developing environmentally sustainable control methods to be used as an alternative to chemical treatments.

Animals↗

PubMed2001

Comparative study of anti-Hypoderma antibody kinetics in sera, single and bulk milk samples of naturally infested cattle.

The investigation was carried out in Basilicata region (Southern Italy) from October 1997 to June 1998. Fifteen dairy cows bred in semiconfined conditions on a farm with a history of hypodermosis were sampled once a month for sera and milk; bulk milk from these animals was also collected monthly from the farm's tanker. Samples were tested for anti-Hypoderma spp. antibodies (Abs) with an ELISA technique and clinical parasitological examination was carried out monthly from January to July on all the animals in order to detect grubs. Blood and single and bulk milk samples yielded similar antibody kinetics and patterns in accordance with results obtained in previous immunological surveys in Italy. All animals were warbled in the spring time. November-January was confirmed to be the most suitable period for seroepidemiological survey for weather conditions in Southern Italy. The ELISA test proved once again to be very useful because it is simple to perform and cost effective. Either blood or milk samples may be used for epidemiological surveys; bulk milk may be very useful for the preliminary detection of hypodermosis on farms or in areas where there is no data available on the diffusion of the disease.

Animals↗

PubMed2001

Goat warble fly infestation by Przhevalskiana silenus (Diptera: Oestridae): immunoepidemiologic survey in the Basilicata region (southern Italy).

The demonstration of serological cross-reactivity between the Hypoderma lineatum antigen and anti-Przhevalskiana silenus antibodies led us to prepare an immunological test (ELISA) for an early diagnosis of goat warble fly infestation. Using the Hypodermosis ELISA-Kit (Vétoquinol Diagnostic, France) produced for the immunodiagnosis of bovine hypodermosis, an epidemiological assay was carried out in Basilicata region where goat breeding is very common and no data are reported with regards to the distribution of goat warble fly infestation. Out of a total of 1,100 flocks and 41,200 goats, 105 randomly extracted flocks proved to be infected and 262 sera out of 1,316 were positive; goat warble fly infestation proved to be present in Basilicata with values similar to those recorded in the surrounding regions (Apulia and Calabria). Statistical evaluation showed highly significant differences between the number of infected flocks in the mountainous areas and hills and those of the mountainous areas and the plain, but no differences between hills and plains. The higher number of positive sera and antibody titres in November-December confirmed that these months are the optimal period for sampling sera in order to perform an early diagnosis. The ELISA test was confirmed to be an easy and economic tool especially when sera sampled within a brucellosis eradication program are used.

Animals↗

PubMed2000

Differentiation by polymerase chain reaction - restriction fragment length polymorphism of some Oestridae larvae causing myiasis.

The cytochrome oxidase I (COI) gene of the most wide-spread Italian species of Oestridae larvae causing myiasis (Gasterophilus spp., Hypoderma bovis, Hypoderma lineatum, Oestrus ovis and Przhevalskiana silenus) was amplified by polymerase chain reaction (PCR) using conserved primers. Restriction fragment length polymorphism (RFLP) of amplicons was also carried out and their restriction profiles compared. A clear genetic difference between the Oestridae larvae examined was demonstrated by using Taq(alpha) I, Hinf I, Rsa I and Hpa II enzymes. No intra-specific variation in RFLPs was detected between the two species of Hypoderma. The results highlight the taxonomic and phylogenetic relationships among larvae belonging to the different subfamilies, and thus offer additional diagnostic and epidemiological instruments.

Animals↗