Clinical and pharmacokinetic characteristics of intracavitary administration of pegylated liposomal encapsulated doxorubicin in dogs with splenic hemangiosarcoma

BACKGROUND: Canine splenic hemangiosarcoma (HSA) is a fatal malignancy, and most affected dogs die within a few months of diagnosis. Most dogs present with signs from tumor rupture, resulting in hemoabdomen and intra-abdominal dissemination. The abdomen is also the main site of disease recurrence. HYPOTHESIS: Intraperitoneal (IP) administration of doxorubicin will delay or prevent intra-abdominal tumor recurrence and prolong survival in dogs with HSA. ANIMALS: Fourteen dogs with splenic HSA. METHODS: A prospective, unmasked, uncontrolled clinical trial. After staging of disease status and splenectomy, pegylated liposomal encapsulated doxorubicin was administered intraperitoneally (1 mg/kg body weight) every 3 weeks for 4 cycles. All dogs were monitored for recurrence of HSA. Samples of plasma and abdominal fluid were collected for measurement of doxorubicin concentration and pharmacokinetic analysis. Nonlinear mixed-effect modeling was used to describe the pharmacokinetics of liposomal doxorubicin administered IP. RESULTS: All 14 dogs died, 12 because of HSA and 2 from other causes. Postmortem examination was performed on 12 dogs. All 12 dogs died because of HSA-related causes and had hepatic metastases and hemoabdomen. The IP-treated dogs had fewer serosal, mesenteric, and omental metastases than historical controls treated with systemic doxorubicin. Results of the postmortem examination and pharmacokinetic analysis confirmed that IP delivery of doxorubicin resulted in an effective drug concentration with a clearance comparable with that after i.v. delivery. CONCLUSIONS AND CLINICAL IMPORTANCE: IP pegylated liposomal encapsulated doxorubicin administration did not prevent intraabdominal recurrence of HSA in dogs.     

Risk factors associated with development of seizures after use of iohexol for myelography in dogs: 182 cases (1998)

OBJECTIVE: To determine prevalence of seizures after use of iohexol for myelography and identify associated risk factors in dogs. DESIGN: Retrospective study. ANIMALS: 182 dogs that received iohexol for myelography in 1998. PROCEDURE: Medical records were reviewed for age, breed, sex, weight, dose and total volume of iohexol, injection site, number of injections, lesion type and location, total duration of anesthesia, duration from time of iohexol injection to recovery, presence and number of seizures, and whether surgery followed the myelogram. RESULTS: 39 (21.4%) dogs had at least 1 generalized seizure during or after myelography. Injection site was strongly associated with prevalence of seizures, and risk of seizure was significantly higher after cerebellomedullary injections, compared with lumbar injections. Mean total volume of iohexol administered to dogs that had seizures was significantly higher, compared with that administered to dogs that did not have seizures, although dosage did not differ between groups. Weight was significantly correlated with risk of seizure, and dogs that weighed > 20 kg (44 lb) had higher prevalence of seizures than dogs that weighed < 20 kg. CONCLUSIONS AND CLINICAL RELEVANCE: It is preferential to administer iohexol via the L5-6 intervertebral space to minimize the risk of seizures. Higher prevalence of seizures in large dogs, compared with smaller dogs, may be caused by administration of larger total volumes of contrast agent per volume of CSF.     

Comparison of the effects of buprenorphine,oxymorphone hydrochloride,and ketoprofen for postoperative analgesia after onychectomy or onychectomy and sterilization in cats

In this prospective, randomized, blinded study, 68 clinically healthy cats that had onychectomy (n = 20), onychectomy and castration (n = 20), or onychectomy and ovariohysterectomy (n = 28) were randomly assigned to one of four postoperative analgesic treatment groups: buprenorphine (0.01 mg/kg body weight, intramuscularly [IM]), oxymorphone hydrochloride (0.05 mg/kg body weight, IM), ketoprofen (2 mg/kg body weight, IM), and placebo (physiological saline). Sedation scores, visual analog pain scores, cumulative pain scores, serum cortisol concentration, and appetite were used to assess postoperative analgesic effect. Buprenorphine demonstrated the highest efficacy with the lowest cumulative pain scores and serum cortisol levels.     

Prognosis for presumed feline vaccine-associated sarcoma after excision: 61 cases (1986-1996)

OBJECTIVE: To evaluate time to first recurrence (TFR) and overall survival in cats with presumed vaccine-associated sarcomas (VAS) treated with excision. DESIGN: Retrospective study. ANIMALS: 61 cats with presumed VAS. PROCEDURE: Medical records of cats that received excision as the only initial treatment for presumed VAS were reviewed to evaluate prognosis. Overall survival curves and TFR were determined. RESULTS: Median TFR was 94 days. Median TFR for tumors treated with excision performed at a referral institution (274 days) was significantly longer than that for tumors excised by a referring veterinarian (66 days). Radical first excision yielded significantly longer median TFR (325 days) than did marginal first excision (79 days). Cats with tumors located on the limbs had longer median TFR (325 days) than cats with tumors located in other sites (66 days). Median overall survival time was 576 days. Significant differences in survival times between groups were not detected. Few cats (13.8%) receiving only surgical treatment had long-term (> 2 years) survival. CONCLUSIONS AND CLINICAL RELEVANCE: Radical first excision of presumed VAS is essential for extended TFR. Current recommendations for vaccination of the distal portions of the extremities are appropriate, because this practice permits radical excision of tumors (amputation) that develop at vaccination sites; however, surgery alone is seldom curative.     

Reproductive Performance and Reconception of Nellore Cows According to Their Pure‐ or Cross‐Bred Calves

The objective of the present research was to evaluate the effect of a calf's genetic group on the productive and reproductive efficiency of its Nellore dam. Fixed‐time artificial insemination was applied to 800 cows using semen extracted from Nellore, Simmental and Angus Red bulls. Four hundred eleven cows calved, producing 119 Nellore, 103 ½Simmental–½Nellore and 189 ½Nellore–½Angus Red calves. The second mating period, which paired Nellore cows with Simmental bulls, was initiated 10 days after parturitions began and lasted for 5 months. Based on the two successive parturitions, the cumulative parturition rate for calving periods of 3, 4 and 5 months was calculated. Although no significant difference was observed for birth weight among the genetic groups, cross‐bred calves weighed, on average, 10% more than did pure‐bred calves at the age of 205 days. Nellore dams experienced a gestation period that was 7 days longer than did the cross‐bred dams, and the former showed a higher parturition rate at 90 and 120 days of the calving season, but not at 150 days (calving rates of 80.6, 76.4 and 76.2% for mothers of Nellore, ½Nellore–½Angus Red and ½Nellore–½Simmental, respectively, p > 0.05). At 90 and 120 days, Nellore dams produced more kg of calf per mated dam. In conclusion, in a short breeding season, Nellore dams nursing pure‐bred Nellore calves were found to have a higher biological efficiency compared with Nellore dams nursing cross‐bred calves.     

Effects of Artemisia annua and Foeniculum vulgare on chickens highly infected with Eimeria tenella (Phylum Apicomplexa)

Background

Intensive poultry production systems depend on chemoprophylaxis with anticoccidial drugs to combat infection. A floor-pen study was conducted to evaluate the anticoccidial effect of Artemisia annua and Foeniculum vulgare on Eimeria tenella infection. Five experimental groups were established: negative control (untreated, unchallenged); positive control (untreated, challenged); a group medicated with 125 ppm lasalocid and challenged; a group medicated with A. annua leaf powder at 1.5% in feed and challenged; and a group treated with the mixed oils of A. annua and Foeniculum vulgare in equal parts, 7.5% in water and challenged. The effects of A. annua and oil extract of A. annua + F. vulgare on E. tenella infection were assessed by clinical signs, mortality, fecal oocyst output, faeces, lesion score, weight gain, and feed conversion.

Results

Clinical signs were noticed only in three chickens from the lasalocid group, six from the A. annua group, and nine from the A. annua + F. vulgare group, but were present in 19 infected chickens from the positive control group. Bloody diarrhea was registered in only two chickens from A. annua group, but in 17 chickens from the positive control group. Mortality also occurred in the positive control group (7/20). Chickens treated with A. annua had a significant reduction in faecal oocysts (95.6%; P = 0.027) and in lesion score (56.3%; P = 0.005) when compared to the positive control. At the end of experiment, chickens treated with A. annua leaf powder had the highest body weight gain (68.2 g/day), after the negative control group, and the best feed conversion (1.85) among all experimental groups.

Conclusions

Our results suggest that A. annua leaf powder (Aa-p), at 1.5% of the daily diet post-infection, can be a valuable alternative for synthetic coccidiostats, such as lasalocid.     

Immunohistochemical characterization of canine prostatic carcinoma and correlation with castration status and castration time

The purpose of this study was to characterize canine prostate cancer using immunohistochemical staining specific for acinar and urothelial/ductal tissue and correlate these results with the dogs' castration status/castration time. Seventy dogs with prostate cancer were included, 71% were castrated and 29% were intact. Compared with an age‐matched control population, castrated dogs were at increased risk of prostate cancer, odds ratio 3.9. Immunohistochemical staining was performed on 58 cases. Forty‐six of the 58 stained positive for cytokeratin 7 (CK 7) (ductal/urothelial origin) and one of the 58 stained positive for prostate‐specific antigen. Dogs with CK 7‐positive tumours were younger when castrated than dogs with CK 7‐negative tumours, 2 versus 7 years (P = 0.03); dogs castrated at ≤2 years of age were more likely to be CK 7‐positive (P = 0.009). These results show that most canine prostatic carcinomas are of ductal/urothelial, androgen‐independent origin. This is consistent with the epidemiological findings, showing increased risk in castrated dogs. Canine prostate cancer may, therefore, not be a realistic model for the human disease.     

Recurrence rates and sites for grade II canine cutaneous mast cell tumors following complete surgical excision.

A retrospective study was performed on 31 dogs with completely excised, grade II, cutaneous mast cell tumors in order to determine recurrence rates and sites. Distant tumor recurrence developed in 22% of dogs, and local tumor recurrence developed in 11% of dogs; however, the vast majority of these animals were incompletely staged initially. Complete surgical excision of grade II mast cell tumors was associated with effective local control in 89% of these dogs. Therefore, adjuvant radiation therapy might not be indicated in the majority of dogs with complete surgical excision.     

Zoonotic visceral and ocular larva migrans

Infection of children with the larval stage of the dog roundworm Toxocara canis usually produces few, if any, clinical signs. In some children, however, the disease may be severe, with permanent ocular or neurologic sequelae. Because the prevalence of infection may exceed 10 per cent in some population subgroups, it is important to understand the modes of transmission and risk factors for infection. The clinical presentations of toxocariasis as well as recommendations for their prevention are described.     

Development Of A Scoring System For The Veterinary Trauma Patient

An animal trauma triage (ATT) scoring system was devised to provide stratification of veterinary trauma patient populations based upon severity of injury. A retrospective population of 101 trauma patients and a prospective population of 88 patients were used to evaluate the predictive power of the ATT scoring system for survival seven days after initial presentation of the emergency service. In Both groups, the mean ATT score for survivors was significantly lower than the mean ATT score for non-survivors. In a logistic regression mode, the ATT score was found to be a significant predictor of the likelihood of survival seven days after initial presentation for both populartions. Each point increase in the ATT score resulted in a 2.3–2.6 times decreased likelihood of survival. The ATT scoring system is a useful objective classification scheme for predicting the likelihood to survive a traumatic incident and can serve as prototype for severity of injuroy scoring systems for the veterinary trauma patient.