Detection of Coxiella burnetii in buffaloes aborted fetuses by IS111 DNA amplification: A preliminary report

The aim of this study was to evaluate by PCR analyses the presence of Coxiella burnetii infection in fetuses of water buffalo (Bubalus bubalis) in the Campania region (Southern Italy). Samples were collected only from aborted fetuses and C. burnetii presence was evaluated by one-tube nested PCR amplification of the IS111 repetitive element. Of the 164 fetuses examined 14 (17.5%) were positive after DNA amplification, showing that C. burnetii occurs in this population of water buffaloes.However, more extensive prevalence studies need to be carried out to define the role of buffaloes as reservoirs for this pathogen and also the role of C. burnetii as an abortive agent in this animal.     

Genetic diversity at alkB locus in Brucella abortus

DNA polymorphism of the alkB gene, a DNA repair gene, was assessed by PCR on Brucella abortus biovars 1 (strains 99, S19, 45/20, RB51 and 2308), 3 (Tulya strain), 5 (B3196 strain) and 6 (870 strain). A DNA repetitive element, named IS711, was detected in all studied biovars 1 and its complete nucleotide sequence was determined. We found that the element in alkB gene, bounded by 14 bp imperfect inverted repeats (IRs), is 840 bp long and appears to duplicate a consensus target site, CTAG. Analysing its nucleotide sequence of both forward and reverse strands, more than 10 open reading frames (ORFs) were found. Two potential transposase coding regions were chosen comparing all possible ORFs with the database. Comparing IS711 elements isolated from Brucella species, including both those characterized in our work and the published ones, differences in length and in nucleotide composition were observed among Brucella species, members of the same species and within the same strain. Our results confirm the heterogeneity of IS711 elements in Brucella genus and suggest the possibility to use this element to assess gene and genome diversity and to identify new molecular markers for Brucella species.     

Experimental Infection of Calves with Bovine Viral Diarrhoea Virus Type-2 (BVDV-2) Isolated from a Contaminated Vaccine

A non-cytopathic strain of BVDV-2 was isolated from a batch of live infectious bovine rhinotracheitis (IBR) vaccine, and inoculated intranasally into four 3-month-old calves. Severe signs of disease developed by days 4 and 6 in three of the calves, free of BVDV and antibodies to BVDV, that had been exposed to the virus. These calves survived the acute phase of the infection and progressively recovered. BVDV was consistently isolated, or the respective viral RNA was detected, in the buffy coats from blood samples collected starting from days 2 or 4 up to days 11 or 14 after the experimental infection. Viral RNA was also detected in sera from these infected calves until the presence in the serum of virus neutralizing antibodies was demonstrated. By contrast, the only calf having pre-existing neutralizing antibodies to BVDV at the start of the study was protected from the disease. No virus was detected at any time after experimental inoculation of this calf. Genomic characterization of the BVDV-2 isolated in cell cultures, or detected in sera from the experimentally infected animals, revealed 100% homology in the nucleotide sequence with the BVDV-2 detected as a contaminant of the live IBR virus vaccine. These findings provided evidence of the infective nature of the contaminant BVDV-2 and of its potential to generate disease outbreaks when inoculated into susceptible animals.     

Introduction into Italy of Gryon pennsylvanicum (Ashmead), an egg parasitoid of the alien invasive bug Leptoglossus occidentalis Heidemann

Leptoglossus occidentalis (Heteroptera, Coreidae), a Nearctic species, was accidentally introduced into Northern Italy in the late 1990s, from where it has spread throughout Europe. The bug causes abortion of immature cones of Pinus pinea L., with economic impact on the pine‐nut industry. As part of a pest control research program, the egg parasitoid Gryon pennsylvanicum Ashmead (Hymenoptera, Platygastridae) was collected from British Columbia, Canada, and legally introduced to a quarantine climatic chamber in Florence, Italy. The egg parasitoid will be tested against native non‐target heteropterans, an environmental impact assessment will be conducted, and a mass rearing method will be developed if appropriate. The ultimate goal is to release G. pennsylvanicum into Italian P. pinea forests for classical biological control of L. occidentalis.     

Physiological host range of Trissolcus mitsukurii,a candidate biological control agent of Halyomorpha halys in Europe

Journal of Pest Science - The invasive stink bug Halyomorpha halys, native to East Asia, is a severe agricultural pest of worldwide importance, and chemical insecticides are largely sprayed for its...     

Laboratory and Clinical Evaluation of a Feia Method for Canine Serum Progesterone Assay

The evaluation of progesterone (P4) concentration is a valuable tool in assessing physiological reproductive events and reproductive disorders in bitches. A reliable and rapid (preferable, point of care) determination of P4 is advisable in most cases. Aims of this study were to evaluate a fluorescence enzyme immunoassay (FEIA) for canine serum P4 concentration by (i) the agreement with liquid chromatography–tandem mass spectrometry (LC/MS/MS), (ii) the association with vaginal cytology and (iii) the accuracy in the prediction of the parturition date calculated from the estimated day of ovulation. Serum samples were collected from client‐owned bitches presented between 2011 and 2014 for the evaluation of their oestrous cycle, pregnancy or reproductive disorders. The agreement between FEIA and LC/MS/MS, evaluated on 19 samples, was statistically significant (R² = 95.7%, p < 0.001), although FEIA showed significantly higher values than LC/MS/MS (p < 0.05). In the different phases of oestrous cycle, as determined by vaginal cytology, P4 concentrations (by FEIA) were statistically different (p < 0.05): anoestrus (n = 7) 0.38 ± 0.14 ng/ml, proestrus (n = 14) 1.04 ± 0.67 ng/ml and oestrus (n = 72) 6.8 ± 7.26 ng/ml. Mean pregnancy length from the estimated day of ovulation was 62.9 ± 1.8 days. In 13 of 22 (59.1%), 19 of 22 (86.3%) and 21 of 22 (95.5%) bitches pregnancy lasted 63 ± 1, 63 ± 2 and 63 ± 3 days, respectively. Three pregnancies were outside the 61–65 days range (60, 60 and 67 days). In conclusion, the FEIA method employed can be considered reliable and, in association with vaginal cytology, effective in evaluating the canine oestrous cycle.     

Entomopathogenic fungi and nematodes against larvae of the chestnut weevil,Curculio elephas (Coleoptera: Curculionidae): a laboratory evaluation

Pest control in chestnut orchards is mainly achieved by chemicals, but there is growing focus on the potential use of biological control agents. The larval susceptibility of the chestnut weevil Curculio elephas L. (Coleoptera: Curculionidae) to different strains/species of entomopathogenic fungi and nematodes was evaluated in laboratory by soil cup bioassays. In the experiments with fungi, a wild strain of Metarhizium anisopliae caused the highest larval mortality (about 90%) compared with a commercial and a wild strain of Beauveria bassiana (80% and 77% respectively). Regarding nematodes, the commercial strain of Heterorhabditis bacteriophora was more effective in the control of chestnut larvae (77% insect mortality) than Steinernema carpocapsae (43%).     

Pest risk analysis of rice root-knot nematode (Meloidogyne graminicola) for the Italian territory

Meloidogyne graminicola is one of the most harmful organisms associated with rice cultivation throughout the world. Until recently, M. graminicola was present only in Asia, parts of the Americas, Madagascar and South Africa. In 2016, it was detected for the first time in mainland Europe (Northern Italy) and subsequently added to the EPPO Alert List. In this study, the risk posed by this nematode to rice in Italy was assessed using an internationally developed pest risk analysis scheme. In the risk assessment section, information about biology, pathways for entry, the likelihood of establishment, spread and negative impact of M. graminicola are reviewed. Internationally, its spread is more likely through the movement of infested host plants, soil or growing medium and non-host plant parts that may have growing medium attached, from areas where this nematode occurs. Migrant waterbirds, machinery and travellers were also considered as possible pathways for entry. The probability of establishment is very likely due to the suitable environmental conditions and the large range of host plant species present in Italy. This and the nematodes’ ability to survive for long periods in low oxygen environments make the control of M. graminicola very difficult.     

Combining physiological host range,behavior and host characteristics for predictive risk analysis of Trissolcus japonicus

Halyomorpha halys is an Asian pentatomid that has recently invaded several countries worldwide, where it has become a severe pest. Classical biological control focused on the scelionid egg parasitoid Trissolcus japonicus appears to be the most promising long-term solution. However, non-target risks need to be included in cost/benefit analyses. Physiological host range tests were conducted by offering T. japonicus females a single hemipteran egg for short (2 h) and long (24 h) exposure periods, and recording the behavior and parasitization acceptance/success during the short exposures. Of the 16 different hemipteran species tested in no-choice experiments, 9 species were accepted and suitable for T. japonicus development. Among pentatomids, Palomena prasina and Rhaphigaster nebulosa were accepted at rates comparable to H. halys, while species accepted at lower rates included Acrosternum heegeri, Carpocoris mediterraneus, C. purpeiripennis, Dolycoris baccarum, Piezodorus lituratus and Peribalus strictus. The other 7 hemipterans tested, including two coreids and one reduviid, were never parasitized. The use of a short-term exposure of 2 h revealed no differences with the 24-h exposure that has been widely used in physiological host range testing. Thus, T. japonicus oligophagy observed in other studies was confirmed by using our extremely simplified laboratory protocol. Moreover, the host egg morphology was correlated with the acceptance rates, permitting us to propose a new predictive approach for non-target studies. However, further research with more complex experimental designs that account for environmental conditions is needed to confirm laboratory predictions of host specificity under actual field conditions.