Evaluation of bacterial and protozoal contamination of commercially available raw meat diets for dogs

OBJECTIVE: To evaluate bacterial and protozoal contamination of commercially available raw meat diets for dogs. DESIGN: Prospective longitudinal study. SAMPLE POPULATION: 240 samples from 20 raw meat diets for dogs (containing beef, lamb, chicken, or turkey), 24 samples from 2 dry dog foods, and 24 samples from 2 canned dog foods. PROCEDURE: Each product was purchased commercially on 4 dates approximately 2 months apart. Three samples from each product at each sampling period were evaluated via bacterial culture for non-type-specific Escherichia coli (NTSEC), Salmonella enterica, and Campylobacter spp. Antimicrobial susceptibility testing was performed on selected isolates. Polymerase chain reaction assays were used to detect DNA from Cryptosporidium spp, Neospora spp, and Toxoplasma spp in samples obtained in the third and fourth sampling periods. RESULTS: One hundred fifty-three of 288 (53%) samples were contaminated with NTSEC. Both raw and prepared foods contained NTSEC during at least 1 culture period. Salmonella enterica was recovered from 17 (5.9%) samples, all of which were raw meat products. Campylobacter spp was not isolated from any samples. In 91 of 288 (31.6%) samples, there was no gram-negative bacterial growth before enrichment and in 48 of 288 (16.7%) samples, there was no aerobic bacterial growth before enrichment. Susceptibility phenotypes were variable. Cryptosporidium spp DNA was detected in 3 samples. CONCLUSIONS AND CLINICAL RELEVANCE: Bacterial contamination is common in commercially available raw meat diets, suggesting that there is a risk of foodborne illness in dogs fed these diets as well possible risk for humans associated with the dogs or their environments.     

Phylogenetic analysis of ORF5 and ORF7 sequences of porcine reproductive and respiratory syndrome virus (PRRSV) from PRRS-positive Italian farms: a showcase for PRRSV epidemiology and its consequences on farm management

We investigated the dynamics of porcine reproductive and respiratory syndrome virus (PRRSV) variability in a range of swine PRRS-positive farms located in Northern Italy, to provide insights into the epidemiology and diffusion of the virus, particularly throughout the entire swine production chain. In this context, we also examined the effectiveness and the critical points of a recently developed gilts acclimatization program in swine breeder farms. To achieve these aims, we designed new primers and determined 64 complete open reading frame 5 (ORF5) sequences, representing Italian PRRSV field strains and the European vaccine Porcilis strain (Intervet); in addition, the more conserved ORF7 of 11 PRRSV strains were sequenced. The domains' prediction of their putative protein sequences was performed as well. Based on these sequences, phylogenetic trees were inferred which revealed a high degree of variability among the PRRSV Italian strains. The outcomes of the phylogenetic analysis showed that the most frequent source of infection in PRRS-positive farms (sow herds, nursery sites, fattening units) was the introduction of animals carrying a new variant and not the modification of already present variants; moreover, the integration of data from phylogenetic analysis and from the clinical and serological status of the swine herds suggested that the acclimatization program could be a valid tool to stabilize the PRRS clinical picture in farms, only when applied in combination with rigorous bio-security routine management and avoid the incoming of new PRRSV variants.     

A SNP mutation affects rhizomania-virus content of sugar beets grown on resistance-breaking soils

Rhizomania is one of the most devastating biotic stresses affecting sugar beet (Beta vulgaris L.). It is caused by Beet necrotic yellow vein virus (BNYVV) vectored by the plasmodiophorid Polymyxa betae K. The only means available to control the disease is the use of genetically resistant varieties. “Rizor” or “Holly” (Rz1) and WB42 (Rz2) have been the most widely used resistance sources in the commercial varieties. Recently, naturally occurring resistance-breaking (RB) rhizomania strains have been identified causing major concerns. The aim of this study was to identify SNP mutations that show associations with resistance to rhizomania in sugar beet plants grown under resistance-breaking (RB)-BNYVV soils. Rhizomania virus content was evaluated by indirect triple-antibody sandwich-ELISA within two F ₂ segregating populations respectively grown on an AYPR and IV-BNYVV strain infected soils. Bulked segregant analysis (BSA) was performed. The resistant and susceptible plants were genotyped with a 384-SNPs panel. Of the 384 SNPs, SNP249 was found to associate with the resistance both to the AYPR strain (R ² = 0.37; P = 0.0004) and to the IV-BNYVV (R ² = 0.09; P = 0.0074). Our results suggested that the SNP249 could be readily applicable for marker-assisted breeding of resistance to AYPR strain of rhizomania.     

The role of silvicultural systems and forest types in preventing soil erosion processes in mountain forests: a methodological approach using cesium-137 measurements

Purpose

Forests play a key role in providing protection against soil erosion. Particularly, the role of vertical forest structure in increasing rainfall interception capacity is crucial for mitigating raindrop impact and reducing splash and rill erosion. For this reason, studies on the relationships between forest structures, the past management, and the observed rates of soil loss are needed. In the last few decades, importance was given to the use of cesium-137 (¹³⁷Cs) as radioactive tracer to estimate soil erosion rates. The ¹³⁷Cs technique is linked to the global fallout of bomb-derived radiocesium which occurred during a period extending from the mid 1950s to the late 1970s.

Materials and methods

The ¹³⁷Cs technique, providing long-term retrospective estimates, could be related to forest treatments applied during the last decades in different sites, also considering the tree species composition. This approach could be useful to compare the effect of different canopy cover and biomass on soil erosion rates related to different tree species. In the work proposed here, a study area dominated by pine and beech high forests located in the Aspromonte Mountains (Calabria, Italy) was selected. The measurements, related to forest structural traits, focusing on canopy cover and biomass, and also on management approaches and forest types, are compared with rates of soil erosion provided by ¹³⁷Cs.

Results and discussion

The overall results suggest that the minimum values of soil loss are documented in areas with higher canopy cover and biomass evidencing the protective effect provided by forests against soil erosion. Also, techniques based on the use of tracers like ¹³⁷Cs proved to be helpful to select the best forest management options useful to optimize the protective role of forests, with the aim to reduce erosion processes in a long-term perspective.

Conclusions

The experiment indicates that care must be taken when new silviculture treatments are planned. These findings are in agreement with what documented by other authors in similar environments but need further studies to confirm the effectiveness of using ¹³⁷Cs in different forest ecosystems.

     

<Emphasis Type="Italic">Vicia faba</Emphasis> plants respond to oviposition by invasive <Emphasis Type="Italic">Halyomorpha halys</Emphasis> activating direct defences against offspring

The invasive stink bug Halyomorpha halys is established in many European and American agro-ecosystems, where it causes severe crop losses. Potential control measures might include enhancement of plant defences. When attacked by herbivorous insects that oviposit on it, the plant may respond by priming direct defences, which might affect the development of future brood. Halyomorpha halys attacks numerous plant species in the invaded areas. Here, we investigated whether Vicia faba plants challenged by H. halys females can impair the development of its offspring through the activation of induced direct defences. We measured the weight and dimension of nymphs that developed on oviposition-experienced plants after 7 and 17 days from hatching. Nymphs that developed on oviposition-experienced plants weighed less compared to those that developed either on control plants or on plants solely subjected to H. halys feeding, and third instars showed shorter dimensions (tibia length). In addition, when oviposition-experienced plants were attacked by nymphs, higher and more rapid expression of two jasmonic acid-dependent genes (cysteine proteinase inhibitor gene and NAI1) was detected, possibly due to a mechanism of priming. Increased expression of the salicylic acid-responsive PR1 gene was also detected in egg-experienced plants, although the response was delayed compared to JA-dependent genes. Our results suggest that V. faba plants recognize H. halys oviposition as a warning signal and pre-activate defences against future nymphal herbivory.     

Assessment of Potential Nutrient Release from Phosphate Rock and Dolostone for Application in Acid Soils

Finding alternative local sources of plant nutrients is a practical, low-cost, and long-term strategy. In this study, laboratory column experiments were conducted in a completely randomized design to evaluate the feasibility of using phosphate rock and dolostone as fertilizers or acid-neutralizing agents for application in tropical acid soils. The dissolution rates of different particle-size fractions(0.063–0.25, 0.25–0.5, and 0.5–2 mm) of both rocks were studied by citric acid solution at p H 4 and 2 and water, with extraction times of 1, 3, 5, 7, 12, 24, 72, 144, 240, and 360 h. The results showed that the dissolution of both rocks depended on the particle size,leaching solution, and extraction time. The dissolution rate of rock-forming minerals increased as the specific surface area increased,corresponding to a decrease in particle size. In all cases, the release kinetics was characterized by two phases: 1) a first stage of rapid release that lasted 24 h and would ensure short-term nutrient release, and 2) a second stage of slow release after 24 h, representing the long-term nutrient release efficiency. Both rocks were suitable as slow-release fertilizers in strongly acid soils and would ensure the replenishment of P, Ca, and Mg. A combination of fine and medium particle-size fractions should be used to ensure high nutrient-release efficiency. Much work could remain to determine the overall impact of considerable amounts of fresh rocks in soils.     

Nodular presentation of Dirofilaria repens infection in a cat mimicking a fibrosarcoma

A cat with multiple subcutaneous nodules suggesting a soft tissue sarcoma by physical and computed tomographic examination was diagnosed as being affected by subcutaneous filariosis based on cytologic and ultrasonographic assessments. Nodules were surgically removed and extracted nematodes were identified by PCR as Dirofilaria repens. Furthermore, DNA of Dipetalonema dracunculoides (syn. Acantocheilonema dracunculoides) was detected by PCR, with no evidence of circulating microfilariae. To the best of the authors' knowledge, this represents the first report describing adults of D repens in multiple subcutaneous nodules in a cat. Cytopathologic examination allowed characterization of the parasitic nature of the nodules. Veterinary practitioners should be aware of the possible nodular presentation of D repens in cats and should include D repens in the differential diagnosis of subcutaneous neoformations in the cat.     

Potential variant of multiple endocrine neoplasia in a dog

This report describes multiple endocrine neoplasia in a dog, which is a rare hereditary disorder characterized by the presence of two or more neoplasms of different endocrine tissues within a patient. A 14 yr old dog was evaluated for polyuria/polydipsia, polyphagia, and abdominal enlargement. Adrenal-dependent hyperadrenocorticism with concomitant left thyroid enlargement and a presumed abdominal metastatic lesion were diagnosed by an adrenocorticotropic hormone stimulation test, ultrasonography, and computed tomography. Trilostane therapy was initiated and resolved the clinical signs for 2 yr at which time the dog presented with left testicular enlargement. The dog was euthanized and was diagnosed with adrenocortical carcinoma, thyroid carcinoma, an abdominal mass compatible with a metastatic lymph node, and bilateral interstitial cell testicular adenomas. To the authors' knowledge, this is the first report to describe the concomitant association of these types of endocrine neoplasms in a dog. The concomitant presence of these neoplasms could represent a potential variant of multiple endocrine neoplasia; however, the presence of the interstitial cell testicular adenomas may have only been an incidental finding. If any of these tumors are diagnosed, veterinarians should perform a thorough clinical assessment to evaluate for the presence of additional endocrine neoplasms or hyperplasia.     

Toxin-associated and other genes in Clostridium perfringens type A isolates from bovine clostridial abomasitis (BCA) and jejunal hemorrhage syndrome (JHS)

This study examined known or possible virulence-associated genes in type A Clostridium perfringens from cases of both bovine clostridial abomasitis (BCA) and jejunal hemorrhage syndrome (JHS) and compared these to isolates from calves that were healthy or had undifferentiated diarrheal illness. A real-time polymerase chain reaction (PCR) assay was used to genotype the 218 C. perfringens isolates. Isolates were sourced from healthy and diarrheic young and mature cattle (n = 191), from calves with confirmed or suspected BCA (n = 22), and from mature cattle with JHS (n = 5). Of 216 isolates (96%), 208 were positive for the cpa gene and 13% (29/218) were positive for atypical cpb2. Three of 8 (37.5%) confirmed BCA isolates, 2 of 13 (15.4%) suspected BCA isolates, and no JHS isolates tested positive for atypical cpb2. As all isolates were negative for cpb, cpb2, cpe, etx, netB, and tpeL, the results of the present study do not support a role for these genes in BCA or JHS. A subset of unique genes identified in 1 bovine clostridial abomasitis isolate (F262), for which a genome sequence is available, was searched for in 8 BCA isolates by PCR. None of the 10 genes was consistently present in all or even in a majority of BCA isolates. Many of these genes were also variably and inconsistently present in type A isolates from calves that did not have BCA. Although a virulence signature to aid in the diagnosis of BCA caused by C. perfringens type A was not identified, further work may discover a gene or group of genes that would constitute such a signature.     

Detection and genetic characterization of porcine circovirus type 2 (PCV2) in pigs from Croatia

Porcine circovirus type 2 (PCV2) from the Circoviridae family has recently been associated with two serious diseases of swine, post-weaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS). During 2002, several outbreaks of clinical disease in pigs with weights ranging from 10 to 70 kg occurred on four farms in different locations in Croatia. The signs were consistent with PMWS and PDNS. Apart from progressive weight loss, pneumonia and/or diarrhoea, multifocal erythematous skin lesions and dermal necrosis were also observed. The PCR results obtained from PCV2 specific oligonucleotide primers confirmed a PCV2 infection. In addition, archive samples that were classical swine fever virus positive and derived from domestic pigs during an outbreak in 1997 were included in this study and one out of the three isolates was found to be positive for PCV2. For a better epizootiological understanding, genetic typing of representative isolates was carried out and compared with available isolates reported in the GenBank databases.