Assessment of regional systolic and diastolic myocardial function using tissue Doppler and strain imaging in dogs with dilated cardiomyopathy

BACKGROUND: Tissue Doppler Imaging (TDI) or strain (St) imaging could provide sensitive indices for early detection and treatment follow-up of canine dilated cardiomyopathy (DCM). Analysis of TDI and St features in dogs with overt DCM is a prerequisite before using these new criteria in prospective screenings of predisposed families or in clinical trials. HYPOTHESIS: Radial and longitudinal right and left myocardial motion, assessed by TDI and St variables, is altered in dogs with DCM. ANIMALS: Case records for 26 dogs; 14 with DCM and 12 healthy controls of comparable age and weight were reviewed. METHODS: A retrospective analysis was conducted of conventional echocardiography, 2-dimensional color TDI, and St imaging data. RESULTS: The DCM group was characterized by decreases in radial and longitudinal systolic velocity gradients of the left ventricular free wall (LVFW), radial and longitudinal absolute values of peak systolic St of the LVFW, and longitudinal systolic right ventricular (RV) velocities (all P < .001 versus control) associated with longitudinal postsystolic contraction waves in 7/14 dogs. Early diastolic LVFW velocities also were decreased for longitudinal (P < .01) and radial (P < .05) motions. All radial LVFW, longitudinal basal LVFW, and RV systolic velocities were negatively correlated with heart rate (P < .01). CONCLUSIONS AND CLINICAL IMPORTANCE: LV contractility along both the short and long axes is impaired in dogs with spontaneous DCM, as is systolic RV and diastolic LVFW function. These myocardial alterations are associated with an inverse force-frequency relationship. Studies now are needed to determine the comparative sensitivity of TDI and St variables for the early detection of canine DCM.     

On the potential of documenting decadal-scale avifaunal change from before-and-after comparisons of museum and observational data across North America

Studies of biodiversity dynamics have been cast on either long(systematics)or short(ecology)time scales,leaving a gap in coverage for moderate time scales of de...     

Disseminated pythiosis in three horses

Three cases of equine subcutaneous pythiosis with dissemination to the internal organs were investigated. The subcutaneous lesions were observed on the mammary gland, nostrils and limbs of the infected horses. Histopathological analysis of the infected tissues revealed a strong eosinophilic reaction, with macrophages, mast cells and giant cells. Sparsely septated hyphal filaments of 4-6 microm diameter were identified in the center of the eosinophilic areas. Specific fluorescent antibody against Pythium insidiosum confirmed the hyphae in the infected tissues in three examined horses. In one of the three cases, the DNA sequences amplified from the infected subcutaneous tissues and internal organs, revealed that P. insidiosum's 18S SSU rDNA amplicons shared 100% identity with those sequences deposit in GenBank. This is the first report confirming by immunochemical and genetic techniques that P. insidiosum can disseminated from superficial to deep structures.     

Anatomy,Morphometry and Radiography in the thoracic limb bones of the Patagonian Huemul Deer (Hippocamelus bisulcus)

The aim of this study was to provide morphometric, anatomic and radiographic data of the thoracic limb bones of the Patagonian Huemul (Hippocamelus bisulcus) including a functional interpretation of this, as a reference for clinical use, biomedical research and teaching purposes. Currently, the Patagonian huemul deer is in danger of becoming extinct due to multiple causes. Research carried out for its conservation has focused mainly on its ecology and pathology, leaving gaps in biological knowledge, which is basic and important for its comprehension. This study was conducted to reveal the gross osteology and radiology features of the thoracic limb bones of the Patagonian huemul deer. The osteological findings suggest the presence of powerful flexor muscles in the scapulohumeral and elbow joints, useful to cushion the jumps. Also, the principal nutrient foramen of Patagonian huemul differs in position with respect to domestic ungulates, which may be important to consider during surgical procedures. Finally, the radiographic data can provide new information about the tissue loading conditions in Patagonian huemul, so that this new knowledge can be of great importance for a better understanding of mechanically induced or adaptive changes in bone produced by habitat or other ecological phenomena.     

Phenotypic and genotypic background underlying variations in fatty acid composition and sensory parameters in European bovine breeds

Background： Consuming moderate amounts of lean red meat as part of a balanced diet valuably contributes to intakes of essential nutrients, in this study, we merged phenotypic and genotypic information to characterize the variation in lipid profile and sensory parameters and to represent the diversity among 15 cattle populations. Correlations between fat content, organoleptic characteristics and lipid profiles were also investigated. Methods： A sample of 436 largely unrelated purebred bulls belonging to 15 breeds and reared under comparable management conditions was analyzed. Phenotypic data -including fatness score, fat percentage, individual fatty acids （FA） profiles and sensory panel tests- and genotypic information from 11 polymorphisms was used. Results： The correlation coefficients between muscle total lipid measurements and absolute vs. relative amounts of polyunsaturated FA （PUFA） were in opposite directions. Increasing carcass fat leads to an increasing amount of FAs in triglycerides, but at the same time the relative amount of PUFAs is decreasing, which is in concordance with the negative correlation obtained here between the percentage of PUFA and fat measurements, as well as the weaker correlation between total phospholipids and total lipid muscle content compared with neutral lipids. Concerning organoleptic characteristics, a negative correlation between fiavour scores and the percentage of total PUFA, particularly to n-6 fraction, was found. The correlation between juiciness and texture is higher than with flavour scores. The distribution of SNPs plotted by principal components analysis （PCA） mainly reflects their known trait associations, although influenced by their specific breed allele frequencies. Conclusions： The results presented here help to understand the phenotypic and genotypic background underlying variations in FA composition and sensory parameters between breeds. The wide range of traits and breeds studied, along with the genotypic information on polymorphisms previo     

Diet composition, herbage intake and digestibility in Inner Mongolian Cashmere goats grazing on native Leymus chinensis plant communities

The botanical composition, intake and digestibility of the diet selected by Inner Mongolian Cashmere goats grazing on a native Leymus chinensis plant community were measured in two grazing periods (June and August) using the n-alkane markers. In each grazing period, 48 Inner Mongolian Cashmere goats (24 wethers and 24 does with an average live weight of 22.1 ± 1.2 kg and 19.6 ± 0.8 kg, respectively) were divided in two groups (G1: grazing group; G2: cage-fed group) of 24 animals each. Based on the observation of G1 grazing behaviour, G2 goats were fed on herbage obtained by a simulative method and were housed in metabolism cages to determine the alkane faecal recoveries. Diet composition was estimated by comparing the odd-chain n-alkane pattern (C₂₅–C₃₅) of the selected plant species with the n-alkane faecal concentrations, corrected for their incomplete faecal recovery. The alkane pair C₃₂:C₃₃ and C₃₆ alkane were used to estimate intake and diet digestibility, respectively. The results showed that the increase of herbage availability from June to August, resulted in higher (P < 0.05) DM, CP, ME, ADF and NDF intake of both wethers and does, with no evident changes in ADF and NDF intake in does., The intake of nutrients differed significantly between wethers and does in both experimental periods, except for NDF in EP1 and ME in EP2. Differences between grazing seasons and goats' sex in nutrients digestibility were not observed. Diet composition indicated seasonal differences, being Sonchus brachyotus, Artemisia frigida and Phragmites communis the main components of the diet in June. However, Suaeda corniculata, Chloris virgata, Xanthium sibiricum and Echinochloa crusgalli became the main diet components in August. Moreover, the sex affected significantly the diet choices in both grazing periods.     

Dairy goat production systems

Goat production concentrated in developing countries (tropics, dry areas), contributes largely to the livelihoods of low and medium income farmers. Farming systems in these areas have evolved to cope with the formidable constraints imposed by harsh natural and economic conditions by adapting integrated crop/livestock production strategies. In Asia, Africa and Latin America, due to its almost exclusive extensive nature, goat production relies mainly on grazing on communal lands that hardly provide the minimum nutrient requirements due to overstocking and degradation. While some of these production systems are becoming semi-intensive, appropriate breeding strategies should be designed to promote conservation and improvement of their unique attributes, such as adaptability, water use efficiency and suitability under harsh climatic conditions. In Europe, dairy goat production is more common around the Mediterranean basin, where it is important from an economic, environmental and sociological perspective to the Mediterranean countries: Spain, France, Italy and Greece. Europe owns only 5.1 % of the world’s dairy goat herds, but produces 15.6 % of the world’s goat milk; this is the only continent where goat milk has such an economic importance and organization. In developing countries the dairy goat sector requires a systemic approach, whereby nutrition, animal health, breeding, know-how, inputs and technologies must be assembled. This would allow the optimization of natural and local resources and would promote the transition from a risk reduction strategy towards an increased productivity strategy. Such an increase would privilege production efficiency based on clean, green and ethical practices for responsible innovation.     

Serotypes and virulence markers of Shiga toxin-producing Escherichia coli (STEC) isolated from dairy cattle in São Paulo State, Brazil

In order to determine the occurrence, serotypes and virulence markers of Shiga toxin-producing Escherichia coli (STEC) strains, 153 fecal samples of cattle randomly selected from six dairy farms in Sao Paulo State, Brazil, were examined for Shiga toxin (Stx) production by the Vero cell assay. Feces were directly streaked onto MacConkey Sorbitol Agar and incubated at 37 degrees C overnight. Sorbitol-negative colonies (maximum 20) and up to 10 sorbitol-positive colonies from each plate were subcultured onto presumptive diagnostic medium IAL. Sorbitol-negative isolates were screened with O157 antiserum for identification of O157:H7 E. coli. Isolates presenting cytotoxic activity were submitted to colony hybridization assays with specific DNA probes for stx1, stx2, eae, Ehly and astA genes. The isolation rate of STEC ranged from 3.8 to 84.6% depending on the farm analysed. STEC was identified in 25.5% of the animals, and most of them (64.1%) carried a single STEC serotype. A total of 202 STEC isolates were recovered from the animals, and except for the 2 O157:H7 isolates all the others expressed cytotoxic activity. The great majority of the STEC isolates carried both stx1 and stx2 genes (114/202, 56.4%) or stx2 (82/202, 40.6%); and whereas the Ehly sequence occurred in most of them (88%) eae was only observed in O157:H7 and O111:HNM isolates. Serotypes O113:H21, O178:H19 and O79:H14 were the most frequent STEC serotypes identified and widely distributed among animals from different farms, while others such as O77:H18, O88:H25 and O98:H17 occurred only in particular farms. This is the first report on the occurrence of STEC in dairy cattle in Sao Paulo State, and the results point to substantial differences in rate of isolation, serotypes and genetic profile of STEC that has been previously described among beef cattle in our community. Moreover, to our knowledge O79:H14 and O98:H17 represent new STEC serotypes, while O178:H19 has only been recently reported in Spain.     

Evaluation of the API 50CH and API ZYM systems for rapid characterization of Clavibacter michiganensis subsp. sepedonicus, causal agent of potato ring rot

API 50CH and API ZYM systems were used to characterize fifty-three strains of Clavibacter michiganensis subsp. sepedonicus from different geographic locations and several reference strains of the same and different species, including other potato pathogens. Clavibacter michiganensis subsp. sepedonicus strains displayed a high level of homogeneity, both in carbohydrate utilization and in enzymatic activity. Using API 50CH and API ZYM it was possible to differentiate C. michiganensis subsp. sepedonicus strains from the remaining taxa analysed in this study, which included representative strains of the other subspecies of C. michiganensis as well as other bacterial pathogens affecting potatoes. Therefore, these systems could be used as an effective method to characterize C. michiganensis subsp. sepedonicus. Such a procedure would constitute an alternative system to the conventional nutritional and physiological identification tests currently included in the official methods employed in the European Union to detect and identify this bacterium. The results obtained with the API systems agreed with the current taxonomic classification of C. michiganensis, clearly separating sepedonicus from the other subspecies belonging to this species.     

Early detection of Neophysopella tropicalis in grapevine leaves and on spore traps by qPCR

Neophysopella tropicalis, one of the causal agents of Asian grapevine leaf rust (AGLR), can cause severe epidemics in Brazil that lead to yield losses in commercial vineyards. An early detection of the pathogen by air sampling of urediniospores on spore traps or in symptomless leaves would be valuable to multiple studies, such as epidemics modelling, risk forecasting, monitoring of pathogen introductions in rust-free areas, and predicting the beginning of epidemics. This study developed a quantitative PCR (qPCR) protocol to quantify N. tropicalis urediniospores attached to adhesive tapes and in grapevine leaves before symptom appearance. A specific primer pair was designed based on the internal transcribed spacer (ITS) sequence region of the AGLR pathogen. Standard amplification curves using genomic DNA from urediniospores of N. tropicalis and from urediniospores attached to adhesive tapes were established. Grapevine leaves inoculated with N. tropicalis were collected at 2, 5, and 7 days postinoculation (dpi). One primer pair (580F/720R) amplified a 140 bp product in all AGLR isolates but did not amplify products of other rust genera, such as Phakopsora, Puccinia, Hemileia, Tranzschelia, Cerotelium, and Coleosporium. As little as 0.1 pg DNA and 10 urediniospores of N. tropicalis attached to adhesive tapes could be detected. qPCR enabled the detection of the pathogen as early as 2 dpi, before symptom appearance. This method can be used to monitor N. tropicalis inoculum in grapevine-growing areas and to quantify symptomless infections of the AGLR pathogen.