Efficacy of injectable and pour-on microdose ivermectin in the treatment of goat warble fly infestation by Przhevalskiana silenus (Diptera, Oestridae)

The prophylactic efficacy of microdoses of injectable and pour-on ivermectin formulations against larval stages of Przhevalskiana silenus was assessed in naturally infected goats in the region of Calabria (southern Italy).Sixty-eight goats from two goat farms were divided into five groups: one group remained untreated, while the other four groups were treated with microdoses of ivermectin (5 and 10 microg/kg injectable formulation and 10 and 20 microg/kg pour-on formulation).The microdoses of ivermectin were fully effective in the treatment of goat warble fly infestation (GWFI) as no larvae emerged from the warbles in the treated groups, while all the larvae emerged in the control groups. Irrespective of the type of formulation used, the difference between the treated groups and the control group was statistically significant (P< 0.001). By contrast, no statistical differences were found between the goats treated with the injectable formulation and those receiving the pour-on applications, and between the two doses of the injectable and pour-on formulations used. Given the plasma concentrations it attains at its lowest dose (0.052 - 0.042 ng/ml for the injectable formulation and 0.030 ng/ml for the pour-on) the injectable formulation seems to offer the most reliable route for the administration of ivermectin microdoses and it is acceptable for milk consumption. The introduction of ivermectin in the early eighties and the use of microdoses in some cases have made it possible to control cattle hypodermosis in large areas of Europe. As with cattle hypodermosis, the administration of ivermectin microdoses in goats is particularly interesting because of the low costs involved and the low levels of residues found in goat milk; it may thus constitute the basis for GWFI control campaigns in areas where the disease is prevalent.     

Transvenous retrograde portography for identification and characterization of portosystemic shunts in dogs

Transvenous retrograde portography for identification and characterization of portosystemic shunts in dogs A method for transvenous retrograde portography (TRP) in dogs suspected to have a portosystemic shunt (PSS) and results in 20 dogs are described. For TRP, dogs were anesthetized and positioned in left lateral recumbency A dual-lumen balloon-tipped catheter was inserted into the right jugular vein and advanced into the azygos vein. The balloon was inflated to occlude the azygos vein, and contrast material was injected during fluoroscopic evaluation. The catheter was then positioned in the caudal vena cava just cranial to the diaphragm. The balloon was again inflated to occlude the vena cava, and contrast material was again injected. Once a shunt was identified, selective catheterization was attempted with a guide wire and angled catheter. A PSS was identified in 18 of the 20 dogs. In 10 of the 18, the shunt vessel could be selectively catheterized, allowing measurement of portal pressures while the shunt was occluded with the balloon. In 1 dog, results of TRP were normal, but subsequent exploratory celiotomy revealed a single extrahepatic PSS, which was surgically attenuated. The other dog in which results of TRP were normal did not have a macroscopic PSS. In dogs suspected to have a PSS, TRP may be a useful adjunctive diagnostic test that is less invasive than operative mesenteric vein portography and allows measurement of portal pressures before and after temporary shunt occlusion.     

Evaluation of the importance of centrifugation as a component of zinc sulfate fecal flotation examinations

Fifty canine fecal samples were evaluated by five flotation procedures to compare the sensitivity of the zinc sulfate (ZnSO4) centrifugation flotation test with ZnSO4 flotation tests using benchtop incubation during the flotation period. One or more parasite species were detected in 40 samples. Results showed that centrifugation with ZnSO4 solution was significantly more likely to detect a positive sample than benchtop procedures. The difference in procedures was due primarily to increased detection of Trichuris eggs and Giardia cysts by centrifugal flotation. No significant difference was seen in the ability of benchtop procedures to detect positive samples when tests sat either for 5 or 10 minutes before examination.     

Further contributions to the genetic aspect of congenital sensorineural deafness in Dalmatians

Sensorineural deafness is a common congenital disorder in Dalmatians and is genetically transmitted. Different modes of inheritance have been proposed and the objective of this study was to study these by segregation analyses using maximum likelihood procedures. Data from 33 complete Dalmatian families were collected and data from 56 single Dalmatians added. This resulted in a total of 575 dogs with 357 known phenotypes. All dogs were clinically evaluated and electrophysiologically tested with brainstem auditory evoked responses.The prevalence of deafness was 16.5% (9.4% unilaterally deaf, 7.1% bilaterally deaf). Females were 4.4% more affected than males but this difference was not significant. Within the same litter, different phenotypic expressions of deafness occurred, which suggested different expressions of the disease. In addition, two data sets were analysed: the first included normal, uni- and bilaterally deaf dogs, the second had normal and deaf Dalmatians. We found that a recessive allele at a single biallelic major locus fitted our data best, although an incomplete penetrance of the recessive homozygotes was observed.     

Searching for veterinary evidence: strategies and resources for locating clinical research.

This article offers information regarding selected veterinary information resources, along with basic search strategies for locating clinical evidence within these resources. No one database provides adequate indexing and abstracting to all literature relevant to the veterinary clinical question. An understanding of a database's syntax and field structure is necessary to formulate a functional search strategy and evaluate the outcome of search results. Flexibility when identifying, selecting, and combining search terms is also required to avoid overlimiting a search.     

Relation between Soil Health, Wave-like Fluctuations in Microbial Populations, and Soil-borne Plant Disease Management

A healthy soil is often defined as a stable soil system with high levels of biological diversity and activity, internal nutrient cycling, and resilience to disturbance. This implies that microbial fluctuations after a disturbance would dampen more quickly in a healthy than in a chronically damaged and biologically impoverished soil. Soil could be disturbed by various processes, for example addition of a nutrient source, tillage, or drying-rewetting. As a result of any disturbance, the numbers of heterotrophic bacteria and of individual species start to oscillate, both in time and space. The oscillations appear as moving waves along the path of a moving nutrient source such as a root tip. The phase and period for different trophic groups and species of bacteria may be shifted indicating that succession occurs. DGGE, Biolog and FAME analysis of subsequent populations in oscillation have confirmed that there is a cyclic succession in microbial communities. Microbial diversity oscillates in opposite direction from oscillations in microbial populations. In a healthy soil, the amplitudes of these oscillations will be small, but the background levels of microbial diversity and activity are high, so that soil-borne diseases will face more competitors and antagonists. However, soil-borne pathogens and antagonists alike will fluctuate in time and space as a result of growing plant roots and other disturbances, and the periods and phases of the oscillations may vary. As a consequence, biological control by members of a single trophic group or species may never be complete, as pathogens will encounter varying populations of the biocontrol agent on the root surface. A mixture of different trophic groups may provide more complete biological control because peaks of different trophic groups occur at subsequent locations along a root. Alternatively, regular addition of soil organic matter may increase background levels of microbial activity, increase nutrient cycling, lower the concentrations of easily available nutrient sources, increase microbial diversity, and enhance natural disease suppression.