The use of magnetic resonance imaging for the assessment of distal limb wounds in horses: A pilot study

The utility of magnetic resonance (MR) imaging in the evaluation of equine solar foot penetrations is well established. The objective of this pilot study was to evaluate the utility of MR imaging in assessment of equine distal limb wounds excluding solar penetrations. Low-field MR images of 23 horses that had previously sustained distal limb wounds were reviewed in consensus by two ECVDI diplomats. Structures (bone; synovial structure; subcutaneous tissue and skin; and ligament/tendon) were identified as normal or abnormal on MR images, radiographs and ultrasound images and reports. All abnormalities were described. The presence of artefacts and their effect on image interpretation were also noted for each modality. Comparisons were made between imaging modalities, and it was noted if MR imaging influenced case management. Abnormalities of the bone were identified in 26% of horses on MR images and 17% of horses on radiographs; there were no osseous abnormalities identified on radiographs that were not identified on MR images, and additional features and better characterisation of lesions were noted on MR images. Tendon/ligament abnormalities were identified in 57% horses on MR and 47% of horses on ultrasound images. Magnetic susceptibility artefacts compromised MR image interpretation in 17% of horses. MR imaging of equine distal limb wounds allowed identification of both osseous and tendon/ligament abnormalities in more cases than either radiography or ultrasonography, and altered case management in 20/23 horses. Although MR imaging should not replace conventional imaging, this study highlights that MR imaging of equine distal limb wounds can yield information not detected on conventional imaging which may direct treatment and affect prognostication.     

Preliminary data on the efficacy of a Giardia vaccine in puppies.

Twenty puppies were vaccinated with a trophozoite-derived Giardia vaccine on day 0 and boosted on day 21 (Group 1); 10 control puppies received only saline (Group 2). Both groups were experimentally infected on day 35 with 1 x 10(6) Giardia duodenalis trophozoites by intraduodenal injection. Immunization provided protection to experimental Giardia infection.     

Passive immunity and serological immune response in dairy calves associated with natural Giardia duodenalis infections

In a previous study, Giardia infection patterns were studied in newborn dairy calves over a 4-month period. Chronic Giardia infections were observed in all calves with initial cyst excretion occurring at approximately 1 month of age. In the work presented here, the passive immunity and serological immune response associated with these Giardia infections were examined. Colostrum and milk samples were collected from the dams of these calves, and monthly serum samples were collected from each calf. The colostrum, milk and sera samples were analyzed by ELISA and Western blot for the presence of anti-Giardia IgG antibodies. In addition, the in vitro anti-Giardia activity of milk and colostrum was examined using a miniculture adherence assay. When examined by ELISA, mean anti-Giardia antibody titres were found to be significantly higher in colostrum compared to milk. The monthly mean serum antibody titres in the calves were not found to differ significantly at any time point during the study. Western blot analysis revealed that colostrum from the dams reacted strongly with many different Giardia antigens between 205 and 7.5kDa, while milk reacted with few antigens in the same size range. Sera collected from the calves when 30 and 60 days of age reacted with few Giardia antigens, but as the calves aged, IgG antibodies in their sera began to react with antigens of 21, 50, 65, 73 and 79kDa. The miniculture adherence assay demonstrated that colostrum had significantly more anti-Giardia activity in vitro compared to milk. These results suggest that the calves in this dairy did not mount a significant humoral immune response against Giardia following infection. However, colostrum contained a high level of anti-Giardia antibodies and exhibited anti-Giardia activity in vitro. Therefore, colostrum may have the potential to provide initial protection against Giardia infections in calves, but the lack of a strong, specific humoral immune response by these calves could account for the high prevalence and chronic duration of the infections.     

Effect of soil moisture and bovine urine on microbial stress

While many studies have examined the cycling of urinary nutrients, few have focused on the effects ruminant urine might have on the soil microbial community. Urine application can cause microbial communities to become stressed, potentially changing community composition and microbial function with subsequent effects on nutrient dynamics. Identification of the factors that stress microbes may assist in explaining ruminant urine effects on nutrient cycling. In this laboratory study bovine urine, with either a high (15.0 g K⁺ l^?1) or low (10.4 g K⁺ l^?1) salt concentration, was added to repacked soil cores maintained at high or low soil moisture contents (70 or 35% water-filled pore space, respectively). Control cores did not receive urine. Microbial stress was measured using phospholipid fatty acid (PLFA) biomarker ratios. Urine addition increased stress as indicated by a decrease in the iso15:0/anteiso15:0 PLFA ratio from >1.35 to <0.95 in both wet and dry soils and by an increase in the 18:1ω9trans/18:1ω9cis PLFA ratio from 1.4 to 1.9 from day 8 onwards in wet soils. Higher stress was indicated by a lower Gram-positive/Gram-negative PLFA ratio in the urine treatments than in the control treatments on day 29 and this may have been a response to the reduction in substrate availability as the experiment progressed. The PLFA biomarkers showed that the salt treatments did not induce stress. Stress induced by urine addition and wet soil treatments was also indicated by principal component analyses and the metabolic quotient for CO₂, respectively. Thus microbial stress was induced by both urine addition and high soil moisture content, but not specifically by increasing the urinary salt concentration.     

Short-term consequences of spatial heterogeneity in soil nitrogen concentrations caused by urine patches of different sizes

The scale of spatial heterogeneity in soil nitrogen (N) concentrations varies considerably in grazed systems, because grazers vary in the volume of urine they excrete. This could affect how urine-N is processed, and subsequently how much N is lost from the system, as diffusion and plant effects on soil nutrient concentrations can be scale-dependent. Two field experiments were performed; one measured the impact of urine patch size (small, medium or large) on soil inorganic N pools and fluxes over time, and the other assessed whether urine patch size affected plant responses and system N retention even if the same total amount of urine was applied. Soil from inside small urine patches retained inorganic N for shorter amounts of time, resulting in lower plant biomass and N uptake than that inside larger patches. Although system nitrogen retention was not affected by patch size, it appeared that larger patches had a greater potential to lose N due to the longer period over which soil inorganic N concentrations remained high. This suggests that systems grazed by larger organisms are more prone to lose N through patch size effects than those grazed by smaller ones.     

Cinnamon Shows Antidiabetic Properties that Are Species-Specific: Effects on Enzyme Activity Inhibition and Starch Digestion

Despite considerable research the evidence around the antidiabetic properties of cinnamon remains equivocal, and this may be due to varietal differences which is an aspect that is understudied. This study systematically compared the anti-hyperglycaemic properties of the four major commercial cinnamon types used around the world (Chinese; Cinnamomum cassia [CC], Indonesian; C. burmanii [IC], Vietnamese; C. loureirii [VC], and Ceylon; C. zeylanicum [SC]). LC-MS analysis showed distinct diffrences in the phytochemical profiles of cinnamon with SC showing the lowest coumarin concentration. CC and IC had the highest polyphenol levels and antioxidant potential, and all four types differed significantly in their content (P?<?0.001). All cinnamon types showed potent species-specific effects on starch digestion enzyme activity inhibition (P?<?0.001), CC was most effective against α-amylase and all four strongly inhibited α-glucosidase compared to acarbose. Cinnamon significantly reduced starch breakdown during oral (P?=?0.006) and gastric (P?=?0.029) phases of gastro-intestinal digestion with IC and SC showing consistent effects. No effects of cinnamon were seen in the intestinal phase. IC, VC and SC showed the greatest potential to inhibit formation of advanced glycation endproducts (AGEs) during digestion. In conclusion, cinnamon demonstrates anti-hyperglycaemic properties, however effects are species-specific with best overall properties seen for Ceylon cinnamon.

     

Ultrasound as a diagnostic tool in the investigation of a pony with intestinal lymphoma

A 21‐year‐old New Forest pony presented for evaluation of lethargy and colic. Transcutaneous abdominal ultrasonography revealed a cavitary, thick walled, mass‐like lesion that appeared continuous with the small intestine. The thick walls of the mass‐like lesion were of heterogeneous echogenicity with hyperechoic foci extending from the hyperechoic luminal surface to within the wall and there was loss of normal wall layering. These findings were confirmed grossly at exploratory celiotomy and histopathological examination of affected tissues confirmed lymphoma. The ultrasound findings facilitated a preoperative presumptive diagnosis that allowed informed decision‐making and aided case management.     

Effects of aggregate size,soil compaction,and bovine urine on N2O emissions from a pasture soil

The dominant N₂O emission source in New Zealand, calculated using the Intergovernmental Panel on Climate Change methodology, is agricultural soils. The largest source of N₂O emissions in New Zealand occurs as a result of excreta deposition onto pasture during grazing. There is a dearth of studies examining the effect of soil compaction and soil aggregate size on N₂O emissions from urine patches in grazed pastures. In this study, we repacked soil cores with four different soil aggregate sizes (<1.0–5.6 mm diameter), applied bovine urine, and then subjected the soil cores to four levels of soil compaction. Fluxes of N₂O were monitored for 37 days after which soil cores were allowed to dry out prior to a rewetting event. There was an interaction between aggregate size and soil compaction with the cumulative loss of N₂O over the first 37 days ranging from 0.3% to 9.6% of the urine-N applied. The highest N₂O emissions occurred from the smallest and most compacted aggregates. Even under the highest levels of compaction the N₂O loss from the large aggregates (4.0–5.6 mm diameter) was <1% of the urine-N applied. Reasons for the observed differences in the N₂O flux from the different-sized aggregates included varying gas diffusivities and higher rates of denitrification in the smallest aggregates, as evidenced by the disappearance of nitrate.