Speed of action and toxicity of acylurea insect growth regulators against Spodoptera exempta (Walk.) and Spodoptera littoralis (Boisd.) larvae: Effect of inter-moult age

Ultra-low volume (ULV) spray bioassays at droplet densities (20–80 drops cm^?2) corresponding to field deposits were used to determine the efficacy of two acylurea insect growth regulators, teflubenzuron (‘Nomolt®’) and flufenoxuron (‘Cascade®’) against three different age groups of third-instar Spodoptera exempta and Spodoptera littoralis larvae. While no response (mortality and/or abnormal moulting with impaired ability to feed) was observed with one-day-old larvae until 48 h after treatment, two-day-old larvae showed some response (27–93% abnormal moulting and 3–10% mortality when larvae were sprayed; 80–100% abnormal moulting and up to 83% mortality when larvae and plants were sprayed) after 24 h and up to 100% mortality at 120 h. Studies with non-feeding, pre-moult larvae showed that cuticular uptake of acylureas was sufficient to affect an appreciable proportion of larvae after 24 h, with up to 100% mortality at 120 h. More detailed studies with pre-moult S. littoralis larvae showed that, while a few larvae which moulted between 1 and 5 h after treatment showed abnormal moulting to the L4 stage, a much larger proportion of larvae which moulted 6–20 h after treatment were affected. Previous studies with S. exempta have shown that different larval instars show similar levels of sensitivity to acylureas. The present work suggests that, while the age distribution within instars has little influence on the end-point mortality of acylureas, it can profoundly modify the speed of response, the majority of larvae within an instar being effectively controlled at the moult following treatment. The significance of these observations in relation to the crop protection activity of acylureas against field populations of Spodoptera larvae is discussed.     

ALIPOMA OF THE EXTENSOR TENDON SHEATHS IN A HORSE

This report describes the identification and surgical removal of a lipoma from the extensor tendon sheaths of a horse. To the authors' knowledge, this is the first report of a lipoma of the extensor tendon sheaths of a horse. Ultrasonographic evaluation was crucial to patient management, providing information regarding the soft tissue mass characteristics, tumor margins and synovial involvement prior to surgical exploration. Surgical removal was performed and was curative.     

Blood smear from a cat: features to "dys"cover

A 4-year-old, spayed female, domestic shorthair cat was presented for lethargy, nonregenerative anemia, and inappetence. Results of a CBC included macrocytic, normochromic, nonregenerative anemia and a glucocorticoid-associated leukogram. On blood smear examination, neutrophils had abnormal features including hyposegmentation and a diffuse chromatin pattern with nuclear filament formation and nuclear blebbing. Microscopic examination of a roll preparation of bone marrow revealed hypolobulated megakaryocytes with asynchronous maturation of nuclei. The granulocytic to erythrocyte (G:E) ratio was 76. Segmented neutrophils had asynchronous maturation and dysplastic features. The entire erythroid lineage was markedly decreased for the degree of anemia and rare dysplastic features were noted in erythroid precursor cells. The interpretation of bone marrow findings was erythroid hypoplasia, megakaryocytic dysplasia, and granulocytic hyperplasia with dysplasia. Histopathologic examination of a bone marrow core sample also revealed myeloid hyperplasia and erythroid hypoplasia. The result of a direct immunofluorescence assay for FeLV performed on the bone marrow roll preparation was positive. A diagnosis of dysmyelopoiesis associated with FeLV infection was made. This case was unique in that the dysplastic changes occurred in cell lines that did not have associated cytopenias. The dysmyelopoiesis most closely resembled myelodysplastic syndrome with refractory cytopenia (MDS-RC); however, secondary dysmyelopoiesis could not be ruled out.     

Prolonged anesthesia using sevoflurane,remifentanil and dexmedetomidine in a horse

HistoryA 10–year old Arabian mare had a slow–growing mass on the lower right mandible and required a large partial mandibulectomy.Physical examinationNo abnormalities were detected apart from the mass.ManagementA temporary tracheostomy was performed pre–operatively. Anesthesia was induced with xylazine followed by ketamine and diazepam. For 13 hours, anesthesia was maintained using sevoflurane, dexmedetomidine and remifentanil infusions, with the exception of surgical preparation time. Intra–operatively, ventilation was delivered through the cuffed tracheotomy tube. Heart and respiratory rates, ECG, arterial pressures, inspired and expired gases, pulse oximetry values and body temperature were monitored. Dobutamine and whole blood were necessary, and romifidine was used to control recovery. Post–operatively, phenylbutazone and buprenorphine given systemically and bupivacaine administered through a wound soaker catheter were used to provide analgesia. Head–shaking from buprenorphine was controlled with acepromazine and detomidine once standing after 87 minutes in recovery. For 3 days after surgery, analgesia was provided with butorphanol, phenylbutazone and bupivacaine. The mare recovered well, appeared comfortable and started eating the following day with no signs of ileus.Follow–upSeven months later, the mare was doing well.ConclusionsSevoflurane, dexmedetomidine and remifentanil infusions were suitable for a long and invasive procedure.     

IMAGING OF A CAT WITH PERIRENAL PSEUDOCYSTS

A 16-year-old, neutered male, domestic short hair cat had abdominal distension and systemic hypertension. Radiography, ultrasonography, excretory urography, and renal scintigraphy were performed to establish the diagnosis and implement appropriate treatment. Bilateral perirenal pseudocysts were confirmed surgically and histopathologically. Following bilateral renal capsulectomy, systemic hypertension decreased and global glomerular filtration rate improved to normal limits. Multiple imaging modalities helped establish the diagnosis and guided implementation of appropriate treatment.     

Comparative analgesic and cardiopulmonary effects of bupivacaine and ropivacaine in the epidural space of the conscious dog

Objective To compare the cardiopulmonary effects and sensory blockade of epidural bupivacaine and ropivacaine. Study Design Prospective randomized study. Animals Six young adult medium‐sized crossbred dogs weighing 25.7 ± 7.1 kg. Method Dogs were chronically implanted with a lumbosacral epidural catheter. Acepromazine sedated dogs received all treatments: 0.5% bupivacaine at 0.14 mL kg^?1 (LB5) or 0.22 mL kg^?1 (HB5); 0.5% ropivacaine at 0.14 mL kg^?1 (LR5) or 0.22 mL kg^?1 (HR5); 0.75% bupivacaine at 0.22 mL kg^?1 (HB7.5) or 0.75% ropivacaine at 0.22 mL kg^?1 (HR7.5). Loss of sensation was tested at the level of the perineum, hind toe webs, flank, and caudodorsal rib areas before injection, and post‐injection (PI) up to 150 minutes PI. Systemic arterial blood pressure and heart rate were recorded before injection, and every 10 minutes PI until 150 minutes PI. Arterial blood gas analyses were performed prior to injection, and at 30, 60 and 150 minutes PI. Results No statistical differences existed between groups for the cardiopulmonary data or time to onset of block. Group HR7.5 had lower systolic (10–70 minutes PI) and diastolic (10–70 minutes PI) blood pressures and group HR5 had lower mean (10–90 minutes PI) and diastolic (10–90 minutes PI) blood pressures compared to baseline. Heart rate was lower compared to baseline in groups LR5 and HB7.5. A significant, but mild metabolic acidosis developed in groups LR5 and HB7.5 (150 minutes PI). No differences were present for the duration of block between groups, but duration of block in the dorsocaudal rib area was shorter in group HR5 compared to HR7.5. Conclusion Epidural ropivacaine and bupivacaine at the doses used have mild effects on the cardiopulmonary system, and extent of block are similar. Clinical Relevance The 0.75% concentration of bupivacaine and ropivacaine at 0.22 mL kg^?1 appeared to contribute to greater success of block (>80%) at dermatomes L₅–L₇.     

Evaluation of anticollagen type I antibody titers in synovial fluid of both stifle joints and the left shoulder joint of dogs with unilateral cranial cruciate disease

OBJECTIVE: To evaluate anticollagen type I antibodies in synovial fluid of the affected stifle joint, the contralateral stifle joint, and the left shoulder joint of dogs with unilateral cranial cruciate ligament (CrCL) rupture during an extended period of 12 to 18 months. ANIMALS: 13 client-owned dogs with CrCL rupture and 2 sham-operated dogs. PROCEDURES: All dogs were examined and arthrocentesis of all 3 joints was performed every 6 months after surgery. Synovial fluid samples were tested for anticollagen type I antibodies by use of an ELISA. RESULTS: Dogs with partial CrCL rupture had higher antibody titers than dogs with complete rupture. Six of 13 dogs ruptured the contralateral CrCL during the study, whereby higher antibody titers were found for the stifle joints than for the shoulder joint. Seronegative dogs or dogs with extremely low antibody titers and 2 dogs with high antibody titers did not sustain a CrCL rupture in the contralateral stifle joint. CONCLUSIONS AND CLINICAL RELEVANCE: In most dogs that had a CrCL rupture of the contralateral stifle joint, a distinct antibody titer gradient toward the stifle joints was detected, suggesting that there was a local inflammatory process in these joints. However, only a small number of sham-operated dogs were used to calculate the cutoff values used to determine the anticollagen type I antibody titers in these patients. Synovial fluid antibodies against collagen type I alone do not initiate CrCL rupture because not all dogs with high antibody titers sustained a CrCL rupture in the contralateral stifle joint.