COMPUTED TOMOGRAPHY-GUIDED FINE-NEEDLE ASPIRATE AND TISSUE-CORE BIOPSY OF INTRATHORACIC LESIONS IN THIRTY DOGS AND CATS

Medical records and computed tomography (CT) images were reviewed retrospectively for 30 animals (27 dogs, two cats, one cougar) in which CT-guided intrathoracic fine-needle aspirates (FNA) (12), core biopsies (10) or both (8) were performed. Sample interpretation was listed as diagnostic or nondiagnostic and nonneoplasia or neoplasia. Diagnostic results were inconclusive in 35% FNA and 17% biopsies. FNA and biopsy interpretations were in agreement in seven patients, one nonneoplasia, and six neoplasia. A clinical diagnosis was made in 65% FNA and 83% biopsies. When 18 patients with confirmed diagnoses were used, overall accuracy for diagnosis was 92% for FNA and biopsy and the sensitivity for neoplasia was 91% using fine needle aspirate and 80% using biopsy. Complications seen on CT images were noted in 43% of patients, four pneumothorax, five pulmonary hemorrhage, and four with both. No clinical manifestations were noted and treatment was not necessary. Significant correlation was noted between complications and penetration of aerated lung, but not with lesion location, type of disease, method of sampling, width of mass and depth of aerated lung penetrated. CT-guided sampling is relatively safe and useful in the diagnosis of intra-thoracic lesions, especially neoplasia. FNA samples are nondiagnostic more often than biopsy samples. Sub-clinical pneumothorax and hemorrhage are common when aerated lung is penetrated.     

Serum concentrations across time after subcutaneous administration of liposome-encapsulated or standard oxymorphone in Rhesus macaques

Our lab has developed a slow‐release liposomal formulation of oxymorphone (LEOx). The purpose of this study was to compare serum concentrations of oxymorphone after administration of LEOx and standard oxymorphone (STDOx) to healthy female rhesus macaques. At baseline, 1 mL of blood was drawn from the femoral vein with the animal in a restraint cage. Primates were divided into two groups: (i) LEOx 1.0 mg kg^–1(n = 4); 2) STDOx 0.1 mg kg^–1(n = 4). Unloaded liposomal vehicle (0.5 mL) was used as a control (n = 2). All treatments were given subcutaneously in a shaved area proximal to the right ileal wing. Femoral venous blood was drawn and serum concentrations of drug were measured at 0.5, 1, 2, 4, 8, 12, 24, 48, 72, 96, and 120 hours. Serum concentrations were measured with ELISA. Serum concentrations were compared between groups and within groups across time with anova . Drug was not detected at any time point in the control group. While sedation was not objectively measured, no animal appeared overly sedate after either treatment. All animals willingly accepted treats and did not appear nauseated or somnolent. Serum concentrations of drug were not significantly different between the two treatment groups from 0 to 2 hours. From 4 hours through 72 hours, however, serum concentrations were significantly higher (p < 0.05) in the animals that received LEOx. By 12 hours, serum concentrations of drug fell below the limit of detection (1.5 ng mL^–1) in animals that received STOx. In animals that received LEOx, serum concentrations at 72 hours were comparable to those measured at 4 hours in animals that received STOx. These results suggest that subcutaneous administration of liposomal oxymorphone yields extended serum levels of drug. These results also suggest that liposomal oxymorphone may provide therapeutic (i.e. analgesic) serum concentrations of drug for 2–3 days after a single subcutaneous administration. Further studies are warranted to assess analgesic efficacy and pharmacokinetics of lipsomal oxymorphone in primates.     

Sedative effects and serum concentrations across time after subcutaneous administration of liposome-encapsulated or standard oxymorphone in healthy dogs

Our lab has developed a slow‐release liposomal formulation of oxymorphone (LEOx). The purpose of this study was to compare sedative effects and serum concentrations of oxymorphone after administration of LEOx and standard oxymorphone (STDOx) to dogs. At baseline, 1 mL of blood was drawn from the cephalic vein and sedation score was recorded. Dogs were divided into four groups (n = 6): (i) LEOx 1.0 mg kg^–1; (ii) LEOx 0.5 mg kg^–1; (iii) STDOx 0.1 mg kg^–1; (iv) STDOx 0.05 mg kg^–1. Unloaded liposomal vehicle (0.5 mL) was used as a control (n = 2). All treatments were given subcutaneously between the scapulae. Sedation score and serum concentration of drug were recorded at 0.5, 1, 2, 4, 8, 12, 16, 24 hours and daily for 5 days. Serum concentrations were measured with ELISA. At all time points, drug was not detected and sedation score was 0 in the control group. Sedation score for group 1 was significantly higher (p < 0.05) at 1 hour than for groups 2,3, and 4. There was no difference in sedation score between treatment groups at any other time. Serum concentrations of drug were significantly higher (p < 0.05) for group 1 at all time points measured after baseline. In groups 2, 3, and 4, serum concentrations of drug fell below the limit of detection (1.5 ng mL^–1) by 24 hours. Serum concentrations after 0.1 mg kg^–1of STDOx were 11.1 ± 3.6 ng mL^–1at 4 hours, which is the recommended time for redosing and presumably reflects the lower end of a therapeutic serum concentration. Serum concentrations were comparable after 1.0 mg kg^–1 of LEOx (10.5 ± 2.4 ng mL^–1) 48 hours after administration. These results suggest that liposomal oxymorphone may provide therapeutic serum concentrations of drug for 2 days after a single subcutaneous administration without undue sedation or other deleterious effects in healthy dogs. Further studies are warranted to assess analgesic efficacy and pharmacokinetics of lipsomal oxymorphone in dogs.     

Electrocardiographic values in Spanish-bred horses of different ages

SUMMARY The duration of electrocardiograph wave forms and intervals were determined in 179 Spanish-bred (Andalusian) horses aged from 1 month to 17 years. The values were compared with those of other breeds, and the relationship between electrocardiographic data and age was examined. High correlation coefficients were found between PR, ST and QT intervals and the age of the horses, and an inverted relation between heart rate and age was found. A multiple range analysis was made and the results suggest that significant changes in duration values and heart rate ocurred at the age of 6 months and in the second year of life.     

Salmonella monitoring programs in Australian feed mills: a retrospective analysis

The availability of safe, commercially prepared stock feed for production animals is an important step in ensuring animal health and welfare and the safety of food animal products for human consumption. Animal feed quality assurance programs include microbiological monitoring of raw materials, mill equipment and finished feed. Over a period of 16 years, 23,963 samples for Salmonella culture and serotyping were collected from 22 stock feed mills. A multivariable generalized linear mixed model (GLMM) was used to identify mill and sample type factors that increase the odds of detecting Salmonella. The odds of detecting a Salmonella positive sample was greatest in samples from raw materials and in mills that processed restricted animal material (RAM). The percentage of positive samples ranged from 7.2% in 2003 to 2.8% in 2017. Of the 1,069 positive samples, 976 were serotyped with 61 different Salmonella serotypes isolated. The serotype most frequently isolated from raw materials was S. Agona, (n = 108) whilst S. Anatum was the serotype most frequently isolated from equipment and finished feed (n = 156). The diversity of Salmonella serotypes differed between mills and different stages of the production line. Microbiological monitoring in the commercial preparation of animal feed in Australian stock feed mills guides the implementation of quality control measures and risk mitigation strategies thereby reducing the prevalence and diversity of potentially zoonotic bacteria such as Salmonella, enhancing food safety for both animal and consumer.     

Transmission studies of Hendra virus (equine morbilli-virus) in fruit bats, horses and cats

Objective To determine the infectivity and transmissibility of Hendra virus (HeV). Design A disease transmission study using fruit bats, horses and cats. Procedure Eight grey-headed fruit bats (Pteropus poliocephalus) were inoculated and housed in contact with three uninfected bats and two uninfected horses. In a second exper iment, four horses were inoculated by subcutaneous injection and intranasal inoculation and housed in contact with three uninfected horses and six uninfected cats. In a third experi ment, 12 cats were inoculated and housed in contact with three uninfected horses. Two surviving horses were inoculated at the conclusion of the third experiment: the first orally and the second by nasal swabbing. All animals were necropsied and examined by gross and microscopic pathological methods, immunoperoxidase to detect viral antigen in formalin-fixed tissues, virus isolation was attempted on tissues and SNT and ELISA methods were used to detect HeV-specific antibody. Results Clinical disease was not observed in the fruit bats, although six of eight inoculated bats developed antibody against HeV, and two of six developed vascular lesions which contained viral antigen. The in-contact bats and horses did not seroconvert. Three of four horses that were inoculated devel oped acute disease, but in-contact horses and cats were not infected. In the third experiment, one of three in-contact horses contracted disease. At the time of necropsy, high titres of HeV were detected in the kidneys of six acutely infected horses, in the urine of four horses and the mouth of two, but not in the nasal cavities or tracheas. Conclusions Grey-headed fruit bats seroconvert and develop subclinical disease when inoculated with HeV. Horses can be infected by oronasal routes and can excrete HeV in urine and saliva. It is possible to transmit HeV from cats to horses. Transmission from P poliocephalus t o horses could not be proven and neither could transmission from horses to horses or horses to cats. Under the experimental conditions of the study the virus is not highly contagious.     

Spatial stability of Avena sterilis ssp. ludoviciana populations under annual applications of low rates of imazamethabenz

Long‐term experiments were conducted in two winter barley fields in central Spain to determine the spatial stability of Avena sterilis ssp. ludoviciana populations under annual applications of low rates of imazamethabenz herbicide. Weed density was sampled every year (over 5 years in the first field and over 3 years in the second) on the same grid locations prior to herbicide application. Although weed patches were stable in their location, weed density decreased in most of the years. In the first field, the populations decreased exponentially over the 5‐year period. The rates of population decline were dependent on the initial density of the population, being higher for the central core of the patches and lower for the low‐density areas. Under the conditions present in this experiment, it was possible to reduce heavy weed patches (up to 1200 seedlings m^?2) down to relatively safe levels (18 seedlings m^?2) in a period of 3 years using a density‐specific control programme, applying low rates of herbicides when weed densities were below a given level (1000 seedlings m^?2). However, under adverse environmental conditions, half rates of the herbicide failed to control the weed populations adequately. The stability of the location of patches of A. sterilis ssp. ludoviciana suggest that weed seedling distributions mapped in one year are good predictors of future seedling distributions. However, the actual densities established each year will depend on the control level achieved the previous year and the climatic conditions present during the establishment period.     

Quantum statistical corrections to dynamic nuclear magnetic resonance

A quantum statistical treatment of the chemical exchange between molecular eigenstates or conformations revealed previously unsuspected dynamic terms in the spin Hamiltonian operator that describes fast exchange. These terms resulted from the effect of nuclear spin on rotational and vibrational relaxation. With the traditional theory, an interpretation of new carbon-13 nuclear magnetic resonance measurements of the chemical shift of methylcyclohexane in solution showed fast-exchange equilibrium constants that were inconsistent with the slow-exchange free-energy difference and were spread over a range of 30 percent for the various carbon-13 positions. Modeling of the new terms indicated that they have the correct magnitude and temperature dependence to reconcile these inconsistencies.