Serum chlortetracycline concentrations in parrots fed medicated seed diets

Various seed diets containing chlortetracycline were fed to large and small parrots to evaluate serum chlortetracycline concentrations. The substitution of dehulled sunflower seed for whole sunflower in the seed mix may have resulted in higher chlortetracycline concentrations in cockatoos and parrots. The serum chlortetracycline concentration achieved for all diets was less than the goal of 1 μg/mL, but the concentrations attained may be useful for therapy.     

Persistent right aortic arch and aberrant left subclavian artery in a white Bengal tiger (Panthera tigris).

A 3-mo-old male white Bengal tiger (Panthera tigris) presented with the chief complaint of regurgitation of solid food since weaning at 2 mo of age. Compared with its littermates, the tiger was in poor body condition and weighed only 10.3 kg when its littermates were estimated at 20-25 kg. Thoracic radiographs showed a megaesophagus cranial to the heart base. A contrast esophagram more clearly outlined the megaesophagus, and fluoroscopy demonstrated normal motility of the caudal esophagus. Endoscopic examination revealed a structure coursing dorsally from right to left over the esophagus and a constrictive band on the left of the esophagus at the heart base. Nonselective angiography confirmed the presence of a persistent right aortic arch, as well as an aberrant left subclavian artery. A left fourth intercostal thoracotomy was performed, and the ligamentum arteriosum was double ligated and divided. The left subclavian artery did not cause significant compromise of the esophagus and was not manipulated at surgery. The tiger recovered well from anesthesia and surgery. Solid food was slowly introduced over a 2-mo period without any regurgitation. The cub gained weight rapidly after surgery.     

Management of equine skull fractures using fixation with polydioxanone sutures

Ten horses presented with severe distortion of the facial contour, crepitus on palpation and mild to moderate epistaxis. Individual horses also showed ocular damage, ptosis, severe dyspnoea and movement of the facial bones concurrent with respiration. The fracture fragments were exposed using a large curvilinear incision and elevated using a retractor, periosteal elevator, chisel or Steinmann pin. The fracture fragments were unstable following reduction and fixation was necessary. Stabilisation was achieved with polydioxanone sutures placed through holes drilled in opposing sides of the fracture lines. Polydioxanone sutures provided good stability and had better handling properties than wire. There was good apposition of fracture edges and minimal complications. Use of polydioxanone sutures can also avoid the expense and complexity of plate fixation in selected cases, and should be considered as an alternative to fixation with stainless steel wire in any facial fracture that adjoins stable bone.     

Sialomucin Complex (Muc4) Expression in Porcine Endometrium During the Oestrous Cycle and Early Pregnancy

The non‐invasive type of implantation in the pig is characterized by the maintenance of a thick glycocalyx coating on the uterine epithelial surface microvilli. Present study investigated the alteration in the sialomucin complex (Muc4) expression during the oestrous cycle and early pregnancy in the pig. Endometrial tissue samples were immunostained with the primary antibody to the Muc4 transmembrane subunit ASGP‐2. Muc4 immunostaining increased in the surface and glandular epithelia between days 5 and 10 of oestrous cycle. Immunostaining continued to increase on day 12 with the greatest intensity of uterine Muc4 immunostaining detected on day 15 of the oestrous cycle and early pregnancy. Endometrial Muc4 expression in cyclic gilts decreased dramatically during early proestrous but continued to remain abundant in the surface and glandular epithelium of pregnant gilts during the period of conceptus attachment to the uterine surface.     

Effects of formulation on the run-off of imidacloprid from turf

Imidacloprid is a pesticide often used to control insect pests on residential lawns and golf courses. To investigate its potential to be transported into non-target aquatic systems by rainfall events, imidacloprid was applied as 5.0 g kg-1 GR and 750 g kg-1 WP to 12 plots planted with bermuda grass set on a 5% slope. The dimethylamine salt of the herbicide 2,4-D was applied simultaneously to the plots in order to normalize the results to prior trials conducted with other pesticides. At a rate of 2.5 cm h-1, 5-cm rainfall events were simulated at 24 and 48 h after application and 2.5-cm events were simulated at 96 and 192 h. After each event water was collected from each plot and analyzed by HPLC for residual insecticide or herbicide. Approximately 1.4% of the insecticide formulated as WP and 1.9% of that formulated as GR was lost from the plots after four run-off events. Of the total mass lost, 64% and 30% respectively occurred in the first and second run-off events for the WP formulation versus 75% and 20% for the GR formulation. These values compare with a total mass export of 2.6% for 2,4-D, of which 95% and 4% of the loss occurred respectively in the first and second run-off events. The maximum concentration of imidacloprid detected in run-off water was 0.49 mg litre-1 and occurred during the first run-off event.     

Chlorothalonil and chlorpyrifos degradation products in golf course leachate

Chlorothalonil and chlorpyrifos are commonly used to control disease and insect pests on golf course greens. While they are relatively immobile in the soil profile, their respective soil degradation products, 4-hydroxy-2,5,6-trichloroisophthalonitrile and 3,5,6-trichloropyridin-2-ol are more polar and may be present in golf course green leachate. To investigate this possibility, six stainless steel lysimeters were constructed into two practice greens at a country club in a northern Atlanta, Georgia suburb. Over a period of 1 year after rainfall events, lysimeter leachate samples were collected into glass bottles, filtered and directly analyzed by HPLC with UV detection. Chlorpyrifos was not detected in any sample and chlorothalonil was detected only in one sample, at a concentration of 0.12 mg liter-1. With a limit of quantitation of 0.05 mg liter-1, hydroxychlorothalonil and trichloropyridinol were detected in 87% and 63% of the samples at maximum and median concentrations of 2.21 and 0.55 mg liter-1 for hydroxychlorothalonil and 1.77 and 0.15 mg liter-1 for trichloropyridinol. Golf course green leachate often mixes with surface water, thus more data may be warranted to determine the persistence and ecological significance of chronic exposure to these compounds of organisms in the aquatic environment.     

LOW-FIELD MAGNETIC RESONANCE IMAGING OF BONE MARROW IN THE LUMBAR SPINE, PELVIS, AND FEMUR IN THE ADULT DOG

The purpose of this study was to describe the appearance of normal bone marrow in seven adult dogs using low-field (0.3 T) magnetic resonance (MR) imaging. The areas imaged included the lumbar spine, pelvis, and femur. T1-weighted, fast spin-echo T2-weighted, and short tau (T1) inversion recovery (STIR) sequences were obtained at all locations. Histopathology was performed on sections from the sixth lumbar vertebral body, the wing of the ilium, and the femur (head and neck, mid-diaphysis, and condyle) for evaluation of cellularity and fat content. The lumbar spine and pelvic marrow MR images were similar in all dogs. The lumbar vertebral bone marrow was uniform, intermediate signal intensity, and isointense to muscle on all sequences. There was variation between dogs in the bone marrow distribution with MR imaging of the femur. In the proximal and mid-diaphysis of the femur there was patchy high-signal intensity on T1- and T2-weighted images, and hypointense foci on the STIR images. The distal femoral metaphysis had a variable pattern ranging from intermediate-to-high signal on T1- and T2-weighted images and intermediate-to-low signal on STIR images. The femoral condyles were uniformly high signal on T1- and T2-weighted images and hypointense on STIR images. Histopathologically there was a normal variation in the bone marrow cellularity. The marrow was normocellular (25–75% cellularity) for all sites examined except the femoral condyles, which were hypocellular (<25% cellularity).