Retinal and optic nerve degeneration in cattle after accidental acrylamide intoxication

A herd of cattle was accidentally exposed to monomeric acrylamide and N-methylolacrylamide. Seven cattle underwent repeated examinations during 6–8 months after exposure. Abnormal pupillary light reflexes (PLR) were observed in one cow. Ophthalmoscopic examination showed progressive retinal degeneration and degenerative changes in the optic nerve heads in this cow. Light and electron microscopic examination revealed pathological changes in the retinae and optic nerves consistent with chronic stages of acrylamide toxicity. Ophthalmic examination and light microscopy did not reveal abnormalities in the retinae or optic nerves in either the rest of the cattle from the herd or in offspring of exposed cattle.     

Effect of summer soil moisture and temperature on the vertical distribution of <Emphasis Type="Italic">Tuber magnatum</Emphasis> mycelium in soil

Tuber magnatum, the Italian white truffle, is the world’s most valuable truffle. Despite the economic importance, its biology and ecology are largely unexplored. This gap of knowledge makes difficult to find reliable methods for its cultivation and to protect and increase the production of the natural productive areas. In this study, the vertical distribution of T. magnatum mycelium in productive soil patches was evaluated using a quantitative PCR (qPCR) approach. Data were then used to develop for the first time a simulation model to predict the mycelial dynamics of T. magnatum at varying soil temperatures and moisture. T. magnatum mycelium was abundant up to 30-cm depth, while the model determined the optimal temperature (20 °C) and water potential (~?0 kPa) for growth of T. magnatum mycelium in soil. Such information could be useful to establish proper irrigation scheduling and to enhance the management of T. magnatum sites, for increasing mycelial growth and fruiting body production.     

Morphology,morphometry and chromatin distribution in llama sperm nuclei

The objectives of this study were as follows: (i) to describe and evaluate the frequencies of different morphologies of llama sperm nuclei, (ii) to determine morphometric values of nuclear parameters, (iii) to describe and estimate the frequencies of different classes of chromatin distribution and (iv) to measure haploid DNA content and analyse its nuclear distribution. The study was performed using ejaculates collected from seven males, and sperm nuclei were stained with the Feulgen reaction. Normal morphology ranged from 78.36% to 93.92%, and abnormalities included short, small, large, pyriform, narrow, micro and round nuclei. Important differences in nuclei considered normal were found between some males. The following average values were obtained for each sperm nuclear morphometric parameter analysed: area 11.64 μm², perimeter 13.16 μm, length 5.12 μm, width 2.81 μm, ellipticity 1.85 and form 0.83. Differences between males were significant for all the parameters (p < .01). Light microscope observations and cytophotometric determinations allowed discriminating between three classes of chromatin distribution: homogeneous, diffuse and showing a clear band. Significant differences between males were found for the frequencies of the three classes (p < .01). Cluster analysis methods were used to estimate the resemblance between males according to the characteristics of their sperm nuclei. A great intermale variability was found for morphological, morphometric and chromatin distribution data. These parameters would have low dependence between them.     

Avian mycobacteriosis in companion birds: 20-year survey

The causative agents of avian mycobacteriosis in pet birds are rarely identified. The aim of this study is to add information about the etiology of avian mycobacteriosis. The identification of mycobacterium species in 27 cases of avian mycobacteriosis in pet birds was investigated by polymerase chain reaction (PCR) and sequencing of a rRNA hypervariable region. Avian mycobacteriosis appeared to be an infrequent diagnosis. Interestingly, a few cases of avian mycobacteriosis were recorded in very young birds. The most commonly affected species were the canary (Serinus canarius), the Eurasian goldfinch (Carduelis carduelis) and the red siskin (Spinus cucullatus). All but one bird were infected with Mycobacterium genavense. Mycobacterium avium was identified only in one case.     

Comparison of four peribulbar anaesthetic techniques: a preliminary study in equine cadavers

ObjectiveTo compare the peribulbar injectate distribution and probability of regional anaesthesia of four peribulbar anaesthetic techniques in equine cadavers.Study designProspective experimental cadaver study.AnimalsA total of 12 isolated equine cadaver heads and 24 eyes.MethodsThe 24 orbits underwent one of four injection techniques (six orbits each) with a mixture (1:4) of contrast medium and saline (CM): 20 mL ventrolateral peribulbar injection (V-20), 20 mL dorsolateral peribulbar injection (D-20), combined ventrolateral and dorsolateral peribulbar injections 10 mL each (VD-20) or 20 mL each (VD-40). To evaluate and score CM distribution at the base of, within the extraocular muscle cone (EOMC), and around the optic nerve (before and after pressure application to the periorbital area), computed tomography was performed. To assess the probability of achieving locoregional anaesthesia, two criteria were applied and both scored as ‘likely’, ‘possible’ or ‘unlikely’. To compare CM distribution scores between injection techniques, Kruskal-Wallis analysis of variance was used. Mann-Whitney U test was used for post hoc comparisons between groups when needed. A p value < 0.05 was considered significant.ResultsThe CM distribution within the EOMC and around the optic nerve circumference was detected as ‘possible’ only after pressure application in seven out of 24 orbits (V-20, 3; D-20, 1; VD-40, 3). It was never considered ‘likely’ either before or after pressure application. The CM distribution at the EOMC base was considered ‘likely’ to provide regional anaesthesia in 50% (V-20), 0% (D-20), 33% (VD-20), 100% (VD-40) and in 66% (V-20), 16% (D-20), 50% (VD-20), 100% (VD-40) before and after applying pressure, respectively.Conclusions and clinical relevanceComplete regional anaesthesia seems more likely using the VD-40 technique, although the authors advise caution due to the risk of potential complications. Future studies are necessary to evaluate the efficacy of the technique in vivo.     

In vitro efficacy of lufenuron against filamentous fungi and blood concentrations after PO administration in horses

Lufenuron is a benzoylphenyl urea-derived insecticide that has been recently introduced as a novel treatment for fungal infections in horses. The purposes of this study were to determine (1) the in vitro efficacy of lufenuron against Aspergillus and Fusarium spp. and (2) the ability of lufenuron to reach efficacious blood concentrations after PO administration in horses. Fungal colonies isolated from diseased equine corneas were tested against lufenuron solutions up to 700 microg/mL. Twenty-one adult horses received 1 of 3 PO lufenuron treatment regimens: 5 mg/kg body weight (BW) q24h for 3 days, 20 mg/kg BW q24h for 3 days, or 60 mg/ kg BW q24h for 1 day. Blood samples were collected up to 96 hours after drug administration and analyzed by high-performance liquid chromatography. Statistical analyses of lufenuron blood concentrations were performed by analysis of variance and Fischer's Least Significant Difference test, with statistical significance set at P < .05. Lufenuron showed no effect on the in vitro growth of Aspergillus or Fusarium spp. Lufenuron was detected in the blood of all but 1 horse and showed no adverse effects. The maximum blood lufenuron concentration (83.5 +/- 58.7 microg/L) was lower than the concentrations proven to be ineffective in vitro in this study. Further therapeutic use of lufenuron as an antifungal agent in horses should be based on proven efficacy against specific strains of clinically relevant fungi with pharmacokinetic data demonstrating sufficient lufenuron concentrations in target tissues.     

Efficacy and safety of suberoylanilide hydroxamic acid (Vorinostat) in the treatment of canine corneal fibrosis

Objective Study aims were to evaluate the safety and efficacy of the Food and Drug Administration‐approved drug Vorinostat [suberoylanilide hydroxamic acid (SAHA)] in the treatment of canine corneal fibrosis using an in vitro model. Methods Healthy donor canine corneas were collected and used to generate primary canine corneal fibroblasts (CCFs) by growing cultures in minimal essential medium supplemented with 10% fetal bovine serum. Canine corneal myofibroblasts, used as a model for corneal fibrosis, were produced by growing CCF cultures in serum‐free medium containing transforming growth factor β1 (1 ng/mL). Trypan blue exclusion assays were used to determine the optimal SAHA dose for this in vitro model. Four hour after culturing with TGFβ1, CCF cultures were treated with 0.06% SAHA for 5 min (group 1) and for 24 h (group 2), representing single and multiple dose treatment regimes, respectively. Cultures were then further incubated in the presence of TGFβ1 (1 ng/μL) under serum‐free conditions until they reached 70% confluence. Trypan blue exclusion, immunocytochemistry, and TUNEL assays were used to evaluate the cytotoxicity of SAHA. Real‐time PCR, western blot analysis, and immunocytochemistry were used to determine the efficacy of SAHA to inhibit canine corneal myofibroblast formation. Results Topical SAHA application in both treatment groups successfully decreased α‐smooth muscle actin expression when compared to the TGFβ1 only treatment group (P < 0.05). Tested SAHA did not affect CCF phenotype or cellular viability and did not cause significant cell death. Conclusions Suberoylanilide hydroxamic acid safely and effectively inhibits TGFβ1‐induced CCFs transformation to myofibroblast in vitro.