Variation in Pathogenicity Among South African Isolates of Phytophthora cinnamomi

Phytophthora cinnamomi isolates from South Africa were evaluated for differences in growth rate in vitro and levels of pathogenicity towards Eucalyptus smithii in the field. Inoculations were conducted in the field in summer and winter in two subsequent years at two locations in South Africa using 59 P. cinnamomi isolates. The isolates differed significantly in growth rate in vitro, as well as in levels of pathogenicity to E. smithii in the field. Growth rate in vitro was significantly influenced by interactions with culture age, geographic origin and genetic background as determined using isozymes. Levels of pathogenicity in the field were influenced by season of inoculation and average minimum temperatures at trial sites. The host from which P. cinnamomi isolates were originally obtained did not significantly affect levels of pathogenicity in the field. Culture age had a significant negative effect on growth rate in vitro and pathogenicity in the field. Significant differences in levels of pathogenicity could be found for different multilocus isozyme genotypes. Geographic origin and mating type of P. cinnamomi isolates had no significant effect on levels of pathogenicity in the field. A positive correlation was found between growth rate in vitro and levels of pathogenicity in the field. Levels of variation for pathogenicity within A1 mating type isolates were significantly lower than for A2 mating type isolates. Results of this study provide valuable information on selection of P. cinnamomi isolates for future resistance/tolerance screening assays of Eucalyptus germplasm in South Africa.     

Synovial fluid proteins in degenerative joint disease in dogs

Concentrations of three immunoglobulins, albumin, ceruloplasmin, alpha-2 macroglobulin and pregnancy zone protein were estimated by immunoelectrophoresis in paired samples of synovial fluid and serum from 12 dogs with degenerative joint disease (DJD) and six normal dogs. The ratios of synovial fluid to serum concentrations (SF/S) of the four non-immunoglobulins showed an almost inverse linear relationship with their molecular weight in both groups. The SF/S were higher in the DJD synovial fluid than in normal synovial fluid. The difference increased with increasing molecular weight and was highly significant for the largest molecules, reflecting an increased permeability and inflammation in the synovial membrane of DJD joints. The SF/S ratios of the three immunoglobulins studied were compared to the diffusion curves of the four non-immunoglobulins. The SF/S ratios of IgM from dogs with DJD exceeded those calculated from the molecular weights. The present observations support the concept that DJD should be considered an inflammatory disease and suggest that immunologic processes may initiate and/or sustain the inflammation.     

Examination of mink (Mustela vison) fed a sulphuric acid preserved fish silage during lactation and growth period. II. Production and pathologic studies correlated to results of clinical-chemical studies

Earlier and present experiments have shown detrimental influence of sulphuric acid preserved fish in mink feed on production parameters, early kit growth and kit mortality. Comparison of the production parameters with clinical-chemical parametres and pathological-anatomical findings give a picture of the tolerated amount of sulphuric acid preserved fish silage in the mink feed during different production periods. It seems that the animals tolerate only small amounts of sulphuric acid preserved fish silage (5-8 per cent) in the total feed during the stress periods of reproduction, lactation and early kit growth but higher amounts (20-30 per cent) during late growth period, where the need of feed is high.     

Additional dietary zinc for weaning piglets is associated with elevated concentrations of serum IGF-I

Two experiments were performed in order to study how weaning and post-weaning dietary zinc level affect serum IGF-I. Further, whether the growth-enhancing effect of 2500 ppm of dietary zinc (Zn2500) and/or 175 ppm of dietary copper (Cu175) in post-weaning diets is associated with elevated serum IGF-I levels in piglets was studied. Experiment 1 included 54 piglets (six litters of nine piglets). One piglet from every litter was assigned to a control group (blood sampled 1 day before weaning). At weaning the remaining eight piglets from every litter were allocated randomly to four dietary treatments with increasing zinc inclusions (Zn100, Zn250, Zn1000, Zn2500). In exp. 2, 48 piglets (six litters of eight piglets) were allocated to four dietary treatments (Zn100, Zn100Cu175, Zn2500, Zn2500Cu175). All piglets in exp. 1 were blood sampled at -1, 1-2, 5-6 or 14-15 days after weaning and in exp. 2 blood samples were taken from all pigs 5-7 days after weaning. Feed intake was recorded per pen (two piglets) and weight gain was recorded for every piglet. Just after weaning feed intake was very low, piglets lost weight and serum IGF-I decreased in exp. 1. However, the piglets fed 2500 ppm of zinc reached pre-weaning levels of serum IGF-I at 14-15 days post-weaning, whereas piglets receiving lower zinc levels showed no changes in serum IGF-I. In exp. 2, additional dietary zinc in weaning diets for piglets was found to be associated with increased feed intake, improved growth rate and increased serum IGF-I. High levels of dietary copper did not affect any of these measurements. Zinc-induced rise in serum IGF-I was partly due to increased feed intake. After correcting for differences in feed intake, zinc significantly increased serum IGF-I. However, to completely separate effects of feed intake from effects of zinc status, pair-feeding should be considered in future studies.     

Investigation of the expression and localization of glucose transporter 4 and fatty acid translocase/CD36 in equine skeletal muscle

OBJECTIVE: To investigate the expression and localization of glucose transporter 4 (GLUT4) and fatty acid translocase (FAT/CD36) in equine skeletal muscle. SAMPLE POPULATION: Muscle biopsy specimens obtained from 5 healthy Dutch Warmblood horses. PROCEDURES: Percutaneous biopsy specimens were obtained from the vastus lateralis, pectoralis descendens, and triceps brachii muscles. Cryosections were stained with combinations of GLUT4 and myosin heavy chain (MHC) specific antibodies or FAT/CD36 and MHC antibodies to assess the fiber specific expression of GLUT4 and FAT/CD36 in equine skeletal muscle via indirect immunofluorescent microscopy. RESULTS: Immunofluorescent staining revealed that GLUT4 was predominantly expressed in the cytosol of fast type 2B fibers of equine skeletal muscle, although several type 1 fibers in the vastus lateralis muscle were positive for GLUT4. In all muscle fibers examined microscopically, FAT/CD36 was strongly expressed in the sarcolemma and capillaries. Type 1 muscle fibers also expressed small intracellular amounts of FAT/CD36, but no intracellular FAT/CD36 expression was detected in type 2 fibers. CONCLUSIONS AND CLINICAL RELEVANCE: In equine skeletal muscle, GLUT4 and FAT/CD36 are expressed in a fiber type selective manner.     

Immunohistochemical identification and fiber type specific localization of protein kinase C isoforms in equine skeletal muscle

OBJECTIVE: To investigate whether protein kinase C (PKC) isoforms are expressed in equine skeletal muscle and determine their distribution in various types of fibers by use of immunofluorescence microscopy. ANIMALS: 5 healthy adult Dutch Warmblood horses. PROCEDURE: In each horse, 2 biopsy specimens were obtained from the vastus lateralis muscle. Cryosections of equine muscle were stained with PKC isoform (alpha, beta1, beta2, delta, epsilon, or zeta)-specific polyclonal antibodies and examined by use of a fluorescence microscope. Homogenized muscle samples were evaluated via western blot analysis. RESULTS: The PKC alpha, beta1, beta2, delta, epsilon, and zeta isoforms were localized within the fibers of equine skeletal muscle. In addition, PKC alpha and beta2 were detected near or in the plasma membrane of muscle cells. For some PKC isoforms, distribution was specific for fiber type. Staining of cell membranes for PKC alpha was observed predominantly in fibers that reacted positively with myosin heavy chain (MHC)-IIa; PKC delta and epsilon staining were more pronounced in MHC-I-positive fibers. In contrast, MHC-I negative fibers contained more PKC zeta than MHC-I-positive fibers. Distribution of PKC beta1 was equal among the different fiber types. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that PKC isoforms are expressed in equine skeletal muscle in a fiber type-specific manner. Therefore, the involvement of PKC isoforms in signal transduction in equine skeletal muscle might be dependent on fiber type.     

Comparison of two-dimensional and three-dimensional systems for kinematic analysis of the sagittal motion of canine hind limbs during walking

OBJECTIVE: To test the hypotheses that kinematic data of the sagittal motion of canine hind limbs during walking obtained with a 2-dimensional (2-D) system correlate well with those obtained with a 3-dimensional (3-D) system and that the data obtained with the 2-D system are repeatable. ANIMALS: 6 adult dogs with no evidence of lameness. PROCEDURES: Hind limb motions of 6 walking dogs were recorded via 2-D video and 3-D optoelectric systems simultaneously. Five valid trials were digitized, and 5 data sets (2-D 60 Hz, 3-D 180 Hz, 3-D sagittal 180 Hz, 3-D 60 Hz, and 3-D sagittal 60 Hz) of a complete gait cycle were created for each dog. In sagittal data sets, 3-D data were reduced to exclude coordinates for mediolateral orientation. Temporospatial parameters; angles of hip, stifle, and tarsal joints; and coefficients of variation of angular measurements of each dog were calculated for each data set. Accuracy of the 2-D analysis was determined by calculating mean absolute differences and estimating agreement between the 2-D and 3-D 180-Hz data sets. RESULTS: Values of joint angles and angular excursions measured with the 2-D system were repeatable and agreed with respective values obtained with the 3-D system. Reduction of the sampling rate had a greater impact on values of kinematic variables obtained with the 3-D system than did elimination of data on mediolateral orientation. CONCLUSIONS AND CLINICAL RELEVANCE: Kinematic analysis using a 2-D video system provided accurate and repeatable data of the sagittal angular motion of canine hind limbs during walking.     

Transport of valine across the small intestinal epithelium in pigs fed different valine levels and Bacillus subtilis

Mutants of Bacillus subtilis overproducing valine (B. subtilis VAL ) could be an approach to supply pigs dietary valine (Val). In the study, 18 gilts were fed: (i) negative diet with a standardized ileal digestible (SID ) Val:Lys of 0.63:1 (Neg); (ii) Neg added B. subtilis VAL (1.28 × 10¹¹ cfu/kg as‐fed) or; (iii) Neg added L‐Val to a Val:Lys of 0.69:1. Using the Ussing chamber method, the study aimed to investigate whether (i) the diets affect intestinal transport of additions of 0, 5, 10 or 20 mmol Val/L from the mucosal to the serosal side and (ii) the B. subtilis VAL contributes to a net transport of Val produced in situ. The results showed that the Isc (ΔIsc_Val) and release of Val to the serosal side solution (S_rel; μmol cm^?2 min^?1) increased with Val addition (linear and quadratic, p  <  .0001) but was similar for 5, 10 or 20 mmol Val/L and not affected by diet. No net transport of in situ produced Val by B. subtilis VAL was detected. In conclusion, feeding a Val‐deficient diet with or without B. subtilis VAL or a Val sufficient diet did not affect the Val transport across intestinal epithelia. No in situ Val production by B. subtilis VAL was observed in the Ussing chambers.     

Echocardiographic indices of age- and gender-dependent cardiac remodeling over the adult lifespan in Irish Wolfhounds

Introduction

Characterizing age- and gender-dependent cardiac remodeling over the adult lifespan in Irish Wolfhounds (IWs) by echocardiography. In people, a life-long cardiac remodeling process has been demonstrated.