N-acetyl- beta -D-glucosaminidase activity in the endometrial epithelium of the cow's uterus during the oestrous cycle and pregnancy

The levels of N-acetyl-beta-D-glucosaminidase (NAGase) were measured in the endometrial epithelial tissue of the bovine uterus during the oestrous cycle and during pregnancy. NAGase levels were significantly (P<0.001) higher in the epithelial tissue of the cow's uterus during the luteal phase of the cycle and during pregnancy than during the non-luteal phase. There were significantly (P<0.001) higher mean NAGase values in the epithelial than the subepithelial layers of the uterus in the two cycle phases and in pregnancy. Leucocyte numbers were significantly (P<0.05 and P<0.001) higher in the cows' uteri during the non-luteal phase than during the luteal phase and pregnancy, respectively. It is concluded that the endometrial epithelial layer is significantly active in terms of NAGase release and that this may be related to increased progesterone concentrations. In addition, the epithelial tissue (not leucocytes) appears to be the main contributor to the total NAGase activity in uterine tissue.     

Land use and forest cover on private parcels in the Upper Midwest USA, 1970 to 1990

This paper analyzes the interactions between land use and forest cover in the Upper Midwest, USA from 1970 to 1990. New data are presented and interpreted to evaluate the effects of land-use changes, especially abandonment of agriculture and dispersed development, on forest cover throughout the region. Forest-cover data were collected from Landsat satellite imagery and land use was interpreted from aerial photographs for land parcels, based on archival maps of land ownership. In general, forest cover increased throughout the region and throughout the period. Simultaneously, the area used for agriculture declined, much of it being converted to natural uses, and the area of land in low density residential development increased. Forest cover increased most rapidly on low density residential lands and in counties in which a large percentage of homes were for seasonal use (i.e., vacation homes). The data suggest that the transformation of the region from an extractive (i.e., forestry and agriculture) to a recreation-based service economy has played a significant role in the increasing forest cover observed throughout the region. This revised version was published online in July 2006 with corrections to the Cover Date.     

Analyzing a forest conversion history database to explore the spatial and temporal characteristics of land cover change in Guatemala's Maya Biosphere Reserve

We analyzed forest clearing and regrowth over a 23-year time period for 21 forest concession and management units within the Maya Biosphere Reserve(MBR), Guatemala. The study area as a whole experienced a clearing rate of0.16%/year from 1974 through 1997. The overall clearing rate appears rather low when averaged over the entire study area over 23 years because most of the reserve was inaccessible. However, despite the granting of legal protection to the MBR in 1990, clearing rates continued to rise, with the highest rates occurring in the most recent time period in the analysis, 1995 to1997. Higher rates of clearing relative to regrowth occurred in newly established communities and in the Reserve's buffer zone, where the clearing of high forest was preferred for pasture development. Exploratory models were built and analyzed to examine the effects of various landscape variables on forest clearing. The different units in the analysis showed different relationships of forest clearing with variables such as forest cover type and distance to access(roads and river corridors). Where available, socio-economic household survey data helped to explain patterns and trends observed in the time series Landsat imagery. A strong relationship between forest clearing and distance to access was demonstrated. More clearing occurred further from roads during later time periods as farmers moved deeper into the forest to find land to clear. Communities inside the MBR that were less dependent on farming had forest clearing to regrowth ratios of one:one or less. These communities used fallow fields in greater proportions than communities in the Reserve's buffer zone. General trends in clearing by forest cover type suggest a preference for clearing high forest (bosque alto) types found on the higher elevation, better-drained soils, and fallow fields,and an avoidance of low-lying, seasonally flooded terrain(bajos). Satellite remote sensing observations of forest clearing and regrowth patterns can provide an objective source of information to complement socio-economic studies of the human driving forces in land cover and land use change. This revised version was published online in July 2006 with corrections to the Cover Date.     

Constitutive expression of a phenylalanine ammonia-lyase gene from Stylosanthes humilis in transgenic tobacco leads to enhanced disease resistance but impaired plant growth

Transgenic tobacco plants expressing a phenylalanine ammonia-lyase cDNA (ShPAL), isolated from Stylosanthes humilis, under the control of the 35S promoter of the cauliflower mosaic virus were produced to test the effect of high level PAL expression on disease resistance. The transgenic plants showed up to eight-fold PAL activity and were slowed in growth and flowering relative to non-transgenic controls which have segregated out the transgene. The expression of the ShPAL transgene and elevated PAL levels were correlated and stably inherited. In T₁ and T₂ tobacco plants with increased PAL activity, lesion expansion was significantly reduced by up to 55% on stems inoculated with the Oomycete pathogen Phytophthora parasitica pv. nicotianae. Lesion area was significantly reduced by up to 50% on leaves inoculated with the fungal pathogen Cercospora nicotianae. This study provides further evidence that PAL has a role in plant defence.     

Effect of adipose-derived nucleated cell fractions on tendon repair in horses with collagenase-induced tendinitis

OBJECTIVE: To assess the potential of adipose-derived nucleated cell (ADNC) fractions to improve tendon repair in horses with collagenase-induced tendinitis. ANIMALS: 8 horses. PROCEDURES: Collagenase was used to induce tendinitis in the superficial digital flexor tendon of 1 forelimb in each horse. Four horses were treated by injection of autogenous ADNC fractions, and 4 control horses were injected with PBS solution. Healing was compared by weekly ultrasonographic evaluation. Horses were euthanatized at 6 weeks. Gross and histologic evaluation of tendon structure, fiber alignment, and collagen typing were used to define tendon architecture. Biochemical and molecular analyses of collagen, DNA, and proteoglycan and gene expression of collagen type I and type III, decorin, cartilage oligomeric matrix protein (COMP), and insulin-like growth factor-I were performed. RESULTS: Ultrasonography revealed no difference in rate or quality of repair between groups. Histologic evaluation revealed a significant improvement in tendon fiber architecture; reductions in vascularity, inflammatory cell infiltrate, and collagen type III formation; and improvements in tendon fiber density and alignment in ADNC-treated tendons. Repair sites did not differ in DNA, proteoglycan, or total collagen content. Gene expression of collagen type I and type III in treated and control tendons were similar. Gene expression of COMP was significantly increased in ADNC-injected tendons. CONCLUSIONS AND CLINICAL RELEVANCE: ADNC injection improved tendon organization in treated tendons. Although biochemical and molecular differences were less profound, tendons appeared architecturally improved after ADNC injection, which was corroborated by improved tendon COMP expression. Use of ADNC in horses with tendinitis appears warranted.     

Induction and recovery characteristics and cardiopulmonary effects of sevoflurane and isoflurane in bald eagles

OBJECTIVE: To compare induction and recovery characteristics and cardiopulmonary effects of isoflurane and sevoflurane in bald eagles. Animals-17 healthy adult bald eagles. PROCEDURES: Anesthesia was induced with isoflurane or sevoflurane delivered in oxygen via a facemask in a crossover design with 4 weeks between treatments. Eagles were intubated, allowed to breathe spontaneously, and instrumented for cardiopulmonary measurements. Time to induction, extubation, and recovery, as well as smoothness of recovery, were recorded. RESULTS: Administration of sevoflurane resulted in a significantly quicker recovery, compared with isoflurane. Temperature, heart rate, and respiratory rate significantly decreased over time, whereas systolic (SAP), diastolic (DAP), and mean arterial blood pressure (MAP) significantly increased over time with each treatment. Temperature, heart rate, SAP, DAP, and MAP were significantly higher with isoflurane. Blood pH significantly decreased, whereas PaCO(2) significantly increased over time with each treatment. Bicarbonate and total carbon dioxide concentrations significantly increased over time with each treatment; however, there was a significant time-treatment interaction. The PaO(2) and arterial oxygen saturation increased over time with isoflurane and decreased over time with sevoflurane with a significant time-treatment interaction. Six eagles developed cardiac arrhythmias with isoflurane, as did 4 with sevoflurane anesthesia. CONCLUSIONS AND CLINICAL RELEVANCE: Isoflurane and sevoflurane administration resulted in smooth, rapid induction of and recovery from anesthesia similar to other species. Isoflurane administration resulted in tachycardia, hypertension, and more arrhythmias, compared with sevoflurane. Sevoflurane was associated with fewer adverse effects and may be particularly beneficial in compromised bald eagles.     

A persistent outbreak of ulcerative enteritis in bobwhite quail (Colinus virginianus)

Ulcerative enteritis is a disease that typically responds well to medication. An outbreak of ulcerative enteritis that was persistent and unresponsive to treatment is described. The outbreak started in semimature birds and progressively spread to younger birds. Confounding factors leading to this persistence were a significant coccidosis problem, a feed mixing error, and suspected antibiotic resistance. Although Clostridium colinum was never isolated, a bacitracin-resistant Clostridium perfringens was cultured from affected birds. Only the combined treatment of the flocks with an anticoccidial and tylosin was effective in controlling clinical disease. Numerous other management and treatment strategies were unsuccessful in lowering the severe mortality.     

Description of empirical movement data from Canadian swine herds with an application to a disease spread simulation model

We report the methods and findings of a survey of Canadian swine producers summarizing farm-types at-risk of foreign animal disease (FAD) and the routine movement of animals, semen and workers among swine farms, as observed during a 42-day period. Of the 311 producers who returned completed questionnaires, 17% represented swine-herds with no swine or semen movement on or off the farm during the 42 days, 57% were sow herds or farrow-to-finish herds with limited movement onto the farm but movement off the farm, and 26% were swine-herds with movements on and off the farm. A substantial number of premises (>50% in some provinces) with swine also kept other animal species on the same premises. We applied the empirical movement data from the survey in a stochastic simulation model to estimate the number of herds infected and the basic regional distribution of infection that could be expected to occur if the FAD was not detected and routine movements were permitted to occur up to 42 days after infection with a FAD of a single randomly selected herd. Forty-five percent of the simulations did not involve spread beyond the index farm, whereas 34.8% involved spread among five or more farms after 42 days of routine movement.     

SPLENIC SEQUESTRATION SCINTIGRAPHY IN THE DOG: A COMPARISON OF DENATURING TECHNIQUES

Five mixed-breed dogs underwent splenic sequestration scintigraphy following intravenous injection of 647.5 to 740 MBq (17.5–20 mCi) of ^99mTechnetium labeled autologous red blood cells (RBCs) that had been chemically denatured using two μg of stannous chloride. Left lateral dynamic images were obtained for 20 minutes after injection. Regions of interest (ROI) were drawn around the splenic body and ventral extremity, ventral liver and caudal abdominal great vessels and time activity curves created. Count density information was obtained and uptake ratios were calculated for the spleen ROI/vessel ROI, liver ROI/vessel ROI and spleen ROI/liver ROI at 1, 2.5, 5, 10, 15 and 20 minutes after injection. Two additional studies using different RBC denaturing procedures were done in four of the five dogs. In the second study, the stannous chloride level was doubled to 4.0 μg, while in the third study, the RBCs were denatured by addition of 2.0 μg of stannous chloride and heating at 49°C for 15 minutes. Progressive splenic uptake of denatured RBCs was seen in all dogs during the first 15 to 20 minutes of each study, no matter which denaturing technique was utilized. Significant increases in the spleen ROI:/vessel ROI and spleen ROI:liver ROI ratios were obtained at 5, 10, 15 and 20 minutes when compared to the 1 minute values for each of the labeling techniques. A significant difference was not identified between the three ratios at 15 minutes between the three labeling techniques. There was a trend of increasing values for each ratio where 2.0 μg of stannous chloride technique being the lowest, 4.0 μg of stannous chloride having an intermediate value and the heated technique had the highest values. The heating technique resulted in higher liver activity and increased variability of the mean liver ROI/vessel ROI ratios at all times (1, 2.5, 5,10, and 15 minutes). Using a non-linear least squares regression analysis, a double exponential equation fit the spleen ROI/vessel ROI and spleen ROI/liver ROI ratios for all three labeling techniques. Imaging of the spleen using all three techniques was acceptable, and a persistent blood pool image would allow for vascular imaging and cardiac gated studies 30 minutes after injection of the denatured, labeled autologous red blood cells. Veterinary Radiology & Ultrasound, Vol. 36, No. I, 1995, pp 57–63.