Effect of topical application of diclofenac liposomal suspension on experimentally induced subcutaneous inflammation in horses

OBJECTIVE: To determine whether 1% diclofenac liposomal suspension (DLS) ointment would be absorbed transdermally and attenuate experimentally induced subcutaneous inflammation in horses. ANIMALS: 7 healthy adult horses. PROCEDURE: Inflammation was produced by injecting 1% sterile carrageenan into subcutaneously implanted tissue cages 8 hours before (time -8) and at the time of application of test ointment. A crossover design was used. Horses received 1 of 2 treatments (topically administered control or DLS ointments) during 48 hours of carrageenan-induced subcutaneous inflammation. A single application of test ointment (7.2 g) was applied over each tissue cage (time 0). Samples of transudate and blood were collected at -8, 0, 6, 12, 18, 24, 30, 36, and 48 hours. Plasma and transudate diclofenac concentrations were determined by use of high-performance liquid chromatography. Transudate concentrations of prostaglandin E2 (PGE2) were determined with a competitive enzyme immunoassay. RESULTS: DLS was absorbed transdermally. The highest concentration (mean +/- SEM, 76.2 +/- 29 ng/mL) was detectable in tissue-cage fluid within 18 hours after application. Minimal concentrations of diclofenac were detectable in plasma. Application of DLS significantly decreased transudate concentrations of PGE2 at 6 and 30 hours. Decreases in PGE2 concentration were observed in the DLS group at all collection times. CONCLUSIONS AND CLINICAL RELEVANCE: A single topical application of DLS resulted in concentrations of diclofenac in transudate within 6 hours and significantly attenuated carrageenan-induced local production of PGE2. Results of this study suggest that DLS is readily absorbed transdermally and may be efficacious for reducing subcutaneous inflammation in horses.     

Observer variability of tibial plateau slope measurement in 40 dogs with cranial cruciate ligament-deficient stifle joints

OBJECTIVE: To determine (1) the inter- and intraobserver variability in measurement of tibial plateau angle (TPA), (2) whether this inter- and intraobserver variability is related to the characteristics of the dog (age, size, and amount of degenerative joint disease [DJD]) and the experience level of the observer, and (3) the extent of any relationship between interobserver variability of TPA and the variability of the observers' selection of the specific cranial and caudal points along the tibial plateau. STUDY DESIGN: Examination of tibial radiographs of 40 dogs clinically affected with a cranial cruciate ligament (CrCL)-deficient stifle joint. METHODS: Eleven different observers, divided into 3 groups based on their level of experience with the tibial plateau leveling osteotomy (TPLO) technique, measured the TPA on all 40 radiographs on 5 different occasions. The degree of DJD present in the stifle joint was independently graded as an overall measure and then again as it specifically related to the cranial and caudal points along the tibial plateau. The total observed variabilities of the TPA were assessed with reference to interobserver differences, intraobserver differences, and among the groups of observers with respect to the different dog characteristics. Finally, the specific points selected on the radiographs were reexamined to determine whether any variability was present in cranial and caudal point selection. RESULTS: The interobserver standard deviation of the TPA measurements for each dog was 0.8 degrees, and the intraobserver standard deviation was 1.5 degrees. The TPA measurements obtained by the 11 observers differed significantly from each other (P <.001); however, there was no significant difference of TPA among the different groups of observers (P =.67). There was no significant correlation observed between either the inter- or intraobserver variability and the dog characteristics. Specific point data and their relationship to the various variables of dog characteristics and inter- and intraobserver TPA variability revealed significant correlations only to the amount of DJD present at the caudal point (P =.001). CONCLUSIONS: Interobserver variation, but no significant group variation, was present. Overall DJD did not appear to be related to the variability in TPA angle measurement. Most of the interobserver variability was attributable to variability in horizontal point selection at both the cranial and caudal points and vertical point selection at the caudal point. It appears that degenerative changes that specifically obscure the points on the tibial plateau, especially at the caudal point, are responsible for most of the interobserver variation. CLINICAL RELEVANCE: The desired postoperative TPA of 5 degrees is dependent on a precise initial measure of TPA preoperatively. This study indicates that there is statistically significant interobserver variability with measurement of TPA, which, therefore, can result in a similar amount of variability with the final tibial plateau slope obtained postoperatively.     

Evaluation of the California mastitis test to detect an intramammary infection with a major pathogen in early lactation dairy cows

The purpose of this study was to evaluate the usefulness of the California mastitis test (CMT) to detect an intramammary infection caused by a major mastitis pathogen in early lactation cows. The gold standard used for comparison was bacteriological culture of single milk samples. The sensitivity (82.4%) and specificity (80.6%) of a positive CMT were highest on the 4th day of lactation.     

Influence of dietary protein and lipid on weight loss in obese ovariohysterectomized cats

OBJECTIVE: To determine effects of dietary lipid and protein on development of hepatic lipidosis (HL) and on physical and biochemical indices following rapid weight loss in cats. ANIMALS: 24 ovariohysterectomized cats. PROCEDURE: Cats were fed a high energy diet until they gained 30% of their ideal body weight and then randomly assigned to receive 1 of 4 weight-reduction diets (6 cats/diet) at 25% of maintenance energy requirements per day. Diets contained a low or high quality protein source and a lipid source deficient or sufficient in long chain essential fatty acids (LCEFA). Serum and plasma samples and liver biopsy specimens were obtained for biochemical analyses and determination of hepatic lipid content before and after weight gain and during and after weight loss. RESULTS: Irrespective of weight-reduction diet fed, all cats lost weight at a comparable rate (4.51 to 5.00 g/d/kg of obese body weight). Three cats developed hepatic lipidosis. Significant changes in plasma insulin, cholesterol, triglyceride, and serum glucose concentrations were detected after weight gain and weight loss in all diet groups, but values for these variables did not differ among groups. CONCLUSIONS AND CLINICAL RELEVANCE: Cats can lose 25 to 30% of their obese body weight over 7 to 9 weeks without developing overt clinical signs of HL, provided that weight-reduction diets are highly palatable, contain a high quality protein, have a source of LCEFA, and are fortified with vitamins and microminerals. However, rapid weight loss may increase risk factors associated with development of diabetes mellitus.     

Pathogenicity of natural and experimental listeriosis in newly hatched chicks

The pathogenicity of Listeria monocytogenes for newly hatched chickens exposed to natural infection was examined. Organisms entered through the alimentary tract and dissemination followed bacteraemia. Among a number of symptoms recorded were unilateral and bilateral toe paralysis. In addition to gross abnormalities in the following tissues, histological lesions were seen in the liver, spleen, heart and kidneys of all infected chicks but brain lesions were observed only in birds with central nervous system involvement. The organism was recovered from some tissues derived from apparently healthy chicks as well as those with listeriosis. The use of trypsin in the isolation process increased the probability of a positive result from tissues, reduced the storage time needed and had no adverse effect on the rate of organism growth.     

Influence of the genotype of Staphylococcus aureus, determined by pulsed-field gel electrophoresis, on dry-period elimination of subclinical mastitis in Canadian dairy herds

By combining information from 2 databases, we investigated the possibility of an association between the genotype of Staphylococcus aureus causing bovine intramammary infection and dry-period cure of subclinical infection. The 1st database contained bacteriologic and cow data from a field study evaluating the efficacy in such infections of a new intramammary dry-cow therapy (DCT) containing tilmicosin phosphate, in comparison with a commercially available DCT containing benzathine cloxacillin. Isolates of S. aureus from that study were frozen and later independently analyzed by pulsed-field gel electrophoresis (PFGE) and macrorestriction DNA fingerprinting. The molecular information, summarized and published elsewhere, constituted the 2nd database. Data from 121 subclinically infected quarters of 92 cows from 40 herds were studied by univariate and multivariable regression analysis. Infection by an isolate of PFGE lineage group D was more likely than infection by an isolate of group A or F to be cured (P < 0.05). Cows infected by lineage group D had a higher linear somatic cell count score (LS) from the last Dairy Herd Improvement test before the dry period than did cows infected by the other lineage groups (P = 0.04). Although the probability of cure was significantly lower for cows with an LS at or above the mean of 5.7 for the study population (P = 0.05), when such a cow was infected with lineage group D, cure was significantly more likely (P < 0.001) than when it was infected by another lineage group. Significantly more (P = 0.02) of the infections treated with tilmicosin (74%) than of those treated with benzathine cloxacillin (53%) were cured, and significantly more (P = 0.05) of the infections by group D (81%) than of those by group A (57%) or group F (54%) were cured. However, there was no difference in cure rate for any PFGE genotype when tilmicosin phosphate was administered; when benzathine cloxacillin was administered, 87% of lineage group D isolates were eliminated, as compared with 46% of group A and 33% of group F isolates (P < 0.05). This research demonstrates that certain genotypes of S. aureus may naturally elicit a greater inflammatory response, yet be more susceptible to elimination by antibiotics in the dry period, than other genotypes.     

Response of vegetation and fire to Little Ice Age climate change: regional continuity and landscape heterogeneity

Late-Holocene climatic conditions in the upper Great Lakes region have changed sufficiently to produce significant changes in vegetation and fire regimes. The objective of this study was to determine how the vegetation mosaic and fire regimes on an oak (Quercus spp.)- and pine (Pinus spp.)-dominated sand plain in northwestern Wisconsin responded to climatic changes of the past 1,200 years. We used pollen and charcoal records from a network of sites to investigate the range of natural variability of vegetation on a 1,500-km² landscape on the southern part of the sand plain. A major vegetation shift from jack pine (Pinus banksiana) and red pine (P. resinosa) to increased abundance of white pine (P. strobus) occurred between 700 and 600 calendar years before present (cal yr BP), apparently corresponding to more mesic conditions regionally. A decrease in charcoal accumulation rate also occurred at most sites but was not synchronous with the vegetation change. At some sites there were further changes in vegetation and fire regimes occurring ～500–300 cal yr BP, but these changes were not as strong or unidirectional as those that occurred 700–600 cal yr BP. Our results suggest that both the composition and the distribution of vegetation of the southern part of the sand plain have been sensitive to relatively small climatic changes, and that the vegetation at the time of European settlement was a transitory phenomenon, rather than a long-term stable condition.     

Morphological diversity among strains of Yersinia ruckeri

There are morphological variations in strains of Yersinia ruckeri, the causal agent of enteric redmouth in salmonid fish. Those variations include subtle differences in cell size and shape, as recorded from growth on a range of bacteriological media. Moreover, from a critical re-evaluation of the phenotypic traits, it appears that these organisms are more closely related to Salmonella than Yersinia.     

Response of four winter wheat cultivars to triallate

Summary Genetic variation among four winter wheat cultivars for response to treatment with triallate was examined. The cultivars showed differential tolerance based on stand count, however, differential tolerance was not seen for any of the other traits examined including visual score, and the mature plant traits, tiller count and yield. Significant effects due to increasing the rate of chemical were observed. An increase in yield was seen at the 0.5 and 1.0 kg/ha rates of triallate. This yield increase was paralleled by trends toward increasing seed number/head and tiller number/unit area. The results indicate that the effect of triallate on wheat has two components. The first component, toxicity, is seen on all cultivars, but the extent of damage varies significantly among cultivars. The second component is positive and leads to an increase in yield without interacting significantly with genotype.