Use of cisplatin-containing biodegradable beads for treatment of cutaneous neoplasia in equidae: 59 cases (2000-2004)

OBJECTIVE: To determine outcome for equids with cutaneous neoplasms treated with cisplatin-containing biodegradable beads, alone or in conjunction with debulking. DESIGN: Retrospective case series. ANIMALS: 56 horses, 1 zebra, 1 donkey, and 1 mule. PROCEDURES: Medical records were reviewed. Follow-up information was obtained through telephone conversations with owners and trainers of the animals. RESULTS: 22 tumors were sarcoids, 6 were fibrosarcomas, 1 was a fibroma, 2 were peripheral nerve sheath tumors, 11 were squamous cell carcinomas, 14 were melanomas (13 gray horses and 1 bay horse), 1 was a lymphosarcoma, 1 was an adenocarcinoma, and 1 was a basal cell tumor. Forty-five (76%) animals underwent conventional or laser debulking of the tumor prior to bead implantation. Forty of 48 (83%) animals for which long-term follow-up information was available were relapse free 2 years after treatment. This included 20 of 22 animals with spindle cell tumors (including 11/13 horses with sarcoids), 6 of 10 animals with squamous cell carcinomas, 13 of 14 animals with melanomas, and 2 of 3 animals with other tumor types. Adverse effects were minimal. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that implantation of cisplatin-containing biodegradable beads, with or without tumor debulking, may be an effective treatment for equidae with various cutaneous neoplasms.     

A survey on neoplasia in domestic species over a 40-year period from 1935 to 1974 in the Republic of South Africa. IV. Tumours occurring in Equidae

A survey was carried out on the neoplasms of horses, donkeys and mules which are recorded in the registration files of the Section of Pathology of the Veterinary Research Institute, Onderstepoort, in the Republic of South Africa, over a 40-year period from 1935 to 1974. A total of 378 tumours are recorded, 339 of which were in horses, 32 in mules and 7 in donkeys. Sarcoids (38%), squamous cell carcinomas (23,5%), fibromas (8,2%), melanomas (8,0%), papillomas (4,5%), fibrosarcomas (3,4%) and lymphosarcomas (3,0%) accounted for 88,6% of the total. Of the 58 sarcoids for which the site or origin was determined, 46,5% occurred on the head, 32,8% on the chest and abdomen, 19% on the limbs especially below the level of the carpus or hock and 1,7% on the neck. Fifty percent of the 89 squamous cell carcinomas occurred on or around the eyes, especially on the eyelids or nictitating membrane, 23% involved the penis and/or prepuce, while just over 20% arose on the skin. The melanomas involved the skin and eye, whilst papillomas originated primarily on the skin and less frequently on the penis.     

Comparison of perioperative versus postoperative intratumoral administration of cisplatin for treatment of cutaneous sarcoids and squamous cell carcinomas in horses

OBJECTIVE: To determine the benefits of reducing the interval between surgical cytoreduction and intratumoral administration of cisplatin. DESIGN: Randomized clinical study. ANIMALS: 70 horses with 89 incompletely resected T2- and T3-stage sarcoids (n = 64) and squamous cell carcinomas (25). PROCEDURE: Horses were given 4 intratumoral treatments of cisplatin at 2-week intervals. The first treatment was given at the time of, or immediately after, surgical resection for horses treated in accordance with the perioperative protocol (group 1). Horses in group 2 were treated with cisplatin after the skin healed following surgical resection in accordance with the postoperative protocol. RESULTS: A difference was not found in duration of overall local tumor control between the 2 groups. Patterns of treatment failures and interval to failure differed between the 2 groups. Length of the surgical scar was the only factor that affected prognosis; an increase in length was associated with a poorer prognosis. A detrimental effect of postoperative treatment was only found in tumors with a high tumor proliferative fraction. Local reactions were similar for the 2 treatment groups, and chronic reactions were not observed. CONCLUSIONS AND CLINICAL RELEVANCE: Intratumoral administration of cisplatin is beneficial for treatment of cutaneous tumors in horses. Tumor repopulation during the interval between surgery and intratumoral administration of cisplatin decreases treatment efficacy. These results provide evidence of rapid tumor repopulation following surgical resection without a lag period for tumors with a high proliferation index. When tumor proliferation index is not known, it may be prudent to use the perioperative protocol.     

Prevalence of equine herpesvirus-1 and equine herpesvirus-4 infections in equidae species in Turkey as determined by ELISA and multiplex nested PCR

In this report we examined the presence of specific antibodies against equine herpesvirus type 1 (EHV-1), and equine herpesvirus type 4 (EHV-4) in several equidae, including mules, donkeys, horses. The presence of EHV-1 and EHV-4 in respiratory diseases of equids, and ability of multiplex nested polymerase chain reaction (PCR) screening in simultaneous diagnosis of horses acutely infected by EHV-1 and EHV-4 were also investigated. Sera from 504 horses, mules and donkeys sampled were tested for the presence of EHV-1 and EHV-4 specific antibodies. Blood samples taken from 21 symptomatic horses and nasal swabs taken from 40 symptomatic horses were tested for the presence of EHV-1 and EHV-4 by a multiplex nested PCR. A total of 14.3% (3/21) of buffy coat samples and 32.5% (13/40) nasal swab samples were found to contain EHV-1 DNA, while 19% (4/21) buffy coat samples and 22.5% (9/40) nasal swab samples were found to be positive for EHV-4 DNA. By species, 14.5% of horses, 37.2% of mules and 24.2% of donkeys tested were EHV-1 seropositive. EHV-4 specific antibodies were detected in 237 (81.7%) of 290 horse sera tested. Results from this investigation demonstrate that EHV-1 and EHV-4 are prevalent throughout the equid population, and that donkeys and mules might also represent an important source of infection for other equids. We also showed that the multiplex nested PCR assay might be useful for diagnosis of mixed respiratory infections in horses due to EHV-1 and EHV-4.     

Bovine papillomavirus DNA in neoplastic and nonneoplastic tissues obtained from horses with and without sarcoids in the western United States

OBJECTIVE: To determine the incidence of bovine papillomavirus (BPV) type 1 or 2 in sarcoids and other samples of cutaneous tissues collected from horses in the western United States. ANIMALS: 55 horses with sarcoids and 12 horses without sarcoids. PROCEDURE: Tissue samples (tumor and normal skin from horses with sarcoids and normal skin, papillomas, and nonsarcoid cutaneous neoplasms from horses without sarcoids) were collected. Tissue samples were analyzed for BPV-1 or -2 DNA, using a polymerase chain reaction (PCR) and restriction fragment length polymorphism. The PCR products from 7 sarcoid-affected horses were sequenced to evaluate percentage homology with expected sequences for BPV-1 or-2. RESULTS: Most (94/96, 98%) sarcoids contained BPV DNA. Sixty-two percent of the tumors examined had restriction enzyme patterns consistent with BPV-2. Thirty-one of 49 (63%) samples of normal skin obtained from horses with sarcoids contained BPV DNA. All samples subsequently sequenced had 100% homology with the expected sequences for the specific viral type. All tissues from healthy horses, nonsarcoid neoplasms, and papillomas were negative for BPV DNA. CONCLUSIONS AND CLINICAL RELEVANCE: Bovine papillomaviral DNA was detected in essentially all sarcoids examined. There appears to be regional variation in the prevalence of viral types in these tumors. The fact that we detected viral DNA in normal skin samples from horses with sarcoids suggests the possibility of a latent viral phase. Viral latency may be 1 explanation for the high rate of recurrence following surgical excision of sarcoids.     

Successful treatment of equine sarcoids with cisplatin electrochemotherapy: a retrospective study of 48 cases

Reasons for performing study: Sarcoids are the commonest form of equine skin tumour. Several therapeutic measures have been described but none is considered to be universally effective. Electrochemotherapy (ECT) is a new anticancer therapy that utilises electrical field pulses to induce increased cell membrane permeability to antitumour hydrophilic drugs, such as cisplatin. The increased intracellular concentration of the drugs has a significant therapeutic benefit. The procedure has not been previously reported in a large number of horses. Objective: To validate ECT as a novel alternative treatment for equine sarcoids. Methods: A retrospective study evaluating the efficacy of cisplatin ECT in the treatment of equine sarcoids was performed. Electrochemotherapy treatments were applied under general anaesthesia at 2 week intervals with or without prior excision or debulking. Electric pulses were directly applied to the lesions following intra‐tumoural injections of an aqueous solution of cisplatin. Results: One‐hundred‐and‐ninety‐four sarcoids on 34 horses, 2 ponies, 11 donkeys and one mule were treated with ECT. The 4 year nonrecurrence rate was 97.9% for animals (47/48) and 99.5% (193/194) for tumours. When ECT was used as a single treatment, a significant influence of tumour size (ρ= 0.55) on the number of treatments required for cure was shown. When prior surgery was performed, there was a significant influence (P<0.001) of the excision quality (complete or incomplete) and the healing mode (closed or open wound) on the number of treatments. The most common adverse effect was a slight oedematous reaction for lesions located on thin skin regions. Conclusion and clinical relevance: Results demonstrate that ECT, with or without concurrent tumour debulking, is an effective alternative for treatment of equine sarcoids.     

Carbon dioxide laser as a surgical instrument for sarcoid therapy--a retrospective study on 60 cases.

The objective of this retrospective clinical study was to evaluate the carbon dioxide laser in the treatment of single and multiple sarcoids in 60 animals (44 horses, 13 donkeys, 2 mules, and 1 pony). Only animals that had been operated on 6 mo or more ago were included. Recurrence, new manifestation rate, and cosmetic outcome were determined. Recurrence was observed in 23 (38%) individuals. Animals with new sarcoid manifestation with or without recurrence of a sarcoid were observed in 35 cases (58%). Cases of scar tissue formation and, rarely, leukotrichia were observed. Animals presented with multiple sarcoids were more predisposed to recurrence. Donkeys showed a significantly lower recurrence rate than horses.     

Pharmacokinetics of sulfamethoxazole and trimethoprim in donkeys, mules, and horses

OBJECTIVE: To compare serum disposition of sulfamethoxazole and trimethoprim after IV administration to donkeys, mules, and horses. ANIMALS: 5 donkeys, 5 mules, and 3 horses. PROCEDURE: Blood samples were collected before (time 0) and 5, 15, 30, and 45 minutes and 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 8, 10, and 24 hours after IV administration of sulfamethoxazole (12.5 mg/kg) and trimethoprim (2.5 mg/kg). Serum was analyzed in triplicate with high-performance liquid chromatography for determination of sulfamethoxazole and trimethoprim concentrations. Serum concentration-time curve for each animal was analyzed separately to estimate noncompartmental pharmacokinetic variables. RESULTS: Clearance of trimethoprim and sulfamethoxazole in donkeys was significantly faster than in mules or horses. In donkeys, mean residence time (MRT) of sulfamethoxazole (2.5 hours) was less than half the MRT in mules (6.2 hours); MRT of trimethoprim in donkeys (0.8 hours) was half that in horses (1.5 hours). Volume of distribution at steady state (Vdss) for sulfamethoxazole did not differ, but Vdss of trimethoprim was significantly greater in horses than mules or donkeys. Area under the curve for sulfamethoxazole and trimethoprim was higher in mules than in horses or donkeys. CONCLUSIONS AND CLINICAL RELEVANCE: Dosing intervals for IV administration of trimethoprim-sulfamethoxazole in horses may not be appropriate for use in donkeys or mules. Donkeys eliminate the drugs rapidly, compared with horses. Ratios of trimethoprim and sulfamethoxazole optimum for antibacterial activity are maintained for only a short duration in horses, donkeys, and mules.     

A survey on the prevalence of internal parasites of equines in macedonia and Thessalia-Greece

A 3-year survey was conducted to determine the incidence of endoparasitic infection of equines in several regions of Macedonia and Thessalia, Greece. Three hundred fecal and 252 blood samples were examined. Fecal examination was carried out using. Teleman and Faust techniques while blood was examined according to the modified Knott technique. The Graham test was also performed. The prevalence of infection found was 62.4% for horses, 75.7% for donkeys and 89.2% for mules. Strongyles (large and small) were the most common parasitic species found, with a corresponding prevalence of 42.5% and 45.6% for horses, 73.0% and 37.8% for donkeys, and 89.2% for mules. Other parasites found were: Eimeria leuckarti (2.6% in horses and 8.1% in donkeys), Anoplocephala perfoliata (0.4% in horses), Parascaris equorum (1.7% in horses), Oxyuris equi (4.1% in horses and 8.7% in mules), Strongyloides westeri (2.2% in horses, 5.4% in donkeys and 10.8% in mules), Dictyocaulus arnfieldi (0.9% in horses and 2.7% in donkeys) and Setaria equina (2.2% in horses and 2.7% in donkeys).     

Pharmacokinetics of flunixin meglumine in donkeys, mules, and horses

OBJECTIVE: To compare serum disposition of flunixin meglumine after i.v. administration of a bolus to horses, donkeys, and mules. ANIMALS: 3 clinically normal horses, 5 clinically normal donkeys, and 5 clinically normal mules. PROCEDURE: Blood samples were collected at time zero (before) and 5, 10, 15, 30, and 45 minutes, and at 1, 1.25, 1.5, 1.75, 2, 2.5, 2.75, 3, 3.5, 4, 4.5, 5, 5.5, 6, and 8 hours after i.v. administration of a bolus of flunixin meglumine (1.1 mg/kg of body weight). Serum was analyzed in duplicate by the use of high-performance liquid chromatography for determination of flunixin meglumine concentrations. The serum concentration-time curve for each horse, donkey, and mule were analyzed separately to estimate noncompartmental pharmacokinetic variables RESULTS: Mean (+/-SD) area under the curve for donkeys (646 +/- 148 minute x microg/ml) was significantly less than for horses (976 +/- 168 minute x microg/ml) or for mules (860 +/- 343 minute x microg/ml). Mean residence time for donkeys (54.6 +/- 7 minutes) was significantly less than for horses (110 +/- 24 minutes) or for mules (93 +/- 30 minutes). Mean total body clearance for donkeys (1.78 +/- 0.5 ml/kg/h) was significantly different from that for horses (1.14 +/- 0.18 ml/kg/h) but not from that for mules (1.4 +/- 0.5 ml/kg/h). Significant differences were not found between horses and mules for any pharmacokinetic variable. CONCLUSION AND CLINICAL RELEVANCE: Significant differences exist with regard to serum disposition of flunixin meglumine in donkeys, compared with that for horses and mules. Consequently, flunixin meglumine dosing regimens used in horses may be inappropriate for use in donkeys.     

Use of a carbon dioxide laser for surgical management of cutaneous masses in horses: 32 cases (1993-2000)

OBJECTIVE: To determine outcome of horses in which cutaneous masses were removed with a carbon dioxide laser. DESIGN: Retrospective study. ANIMALS: 32 horses. PROCEDURE: Medical records of horses with 1 or more cutaneous masses treated with a carbon dioxide laser were examined. Follow-up information was obtained through telephone interviews with owners and referring veterinarians. RESULTS: Cutaneous masses were classified as sarcoids (15 horses), neoplastic masses other than sarcoids (squamous cell carcinoma [91; fibroma [1]; and melanoma [1]), and nonneoplastic masses (6). Minimum follow-up time was 6 months. Five sarcoids and 2 squamous cell carcinomas recurred. Seven (21%) horses had complications associated with dehiscence of wounds that had been closed primarily or failure of wound healing because of recurrence of the mass. Twenty-six (81%) owners were satisfied with the cosmetic appearance following surgery. CONCLUSION AND CLINICAL RELEVANCE: Results suggest that a carbon dioxide laser may be effective for treatment of cutaneous masses in horses.     

Evaluation of microchip migration in horses, donkeys, and mules

OBJECTIVE: To determine whether microchips used for identification migrate after implantation in horses, donkeys, and mules. DESIGN: Prospective study. ANIMALS: 53 horses, donkeys, and mules. PROCEDURE: Twenty horses that had had microchips implanted in the nuchal ligament at a veterinary teaching hospital from 1996 through early 2000 were included (group 1), and the poll-to-withers distance and location of the microchip were determined, measured, and recorded. Additionally, the poll-to-withers distance was measured in 16 horses, 12 donkeys, and 5 mules (group 2), and microchips were implanted in the nuchal ligament on the left side of the neck. Forty-two to 67 days after implantation, the location of the microchip was determined, measured, and recorded. RESULTS: Microchips implanted in the nuchal ligament < or = 4 years previously did not migrate. All microchips were detected with a multimode identification tag reader from the left side of the neck in the midcervical region, and microchips were located at the midpoint between the poll and withers for all 53 horses, donkeys, and mules. CONCLUSIONS AND CLINICAL RELEVANCE: Microchips implanted in the nuchal ligament < or = 4 years earlier did not migrate in horses. Microchips may be useful for identification in horses.     

Electroencephalographic Responses to a Noxious Surgical Stimulus in Mules,Horses, and Ponies

The aim of this study was to investigate the electroencephalographic (EEG) response of equidae to a castration stimulus. Study 1 included 11 mules (2½–8 years; 230–315 kg) and 11 horses (1½–3½ years; 315–480 kg); study 2 included four ponies (15–17 months; 176–229 kg). They were castrated under halothane anesthesia after acepromazine premedication (IV [study 1] and intramuscular [study 2]) and thiopental anesthetic induction. Animals were castrated using a semiclosed technique (study 1) and a closed technique (study 2). Raw EEG data were analyzed and the EEG variables, median frequency (F50), total power (Ptot), and spectral edge frequency (F95), were derived using standard techniques at skin incision (skin) and emasculation (emasc) time points. Baseline values of F50, Ptot, and F95 for each animal were used to calculate percentage change from baseline at skin incision and emasculation. Differences were observed in Ptot and F50 data between hemispheres in horses but not mules (study 1) and in one pony (study 2). A response to castration (>10% change relative to baseline) was observed in eight horses (73% of animals) and four mules (36% of animals) for F50 and nine horses (82%) and four mules (36%) for Ptot. No changes in F95 data were observed in any animal in study 1. Responses to castration were observed in three ponies (75% of animals) for F50, one pony (25%) for F95, and all ponies for Ptot. Alteration of acepromazine administration and castration technique produced a protocol that identified changes in EEG frequency and power in response to castration.     

Prevalence and Chemotherapy of Parascaris equorum in Equines in Pakistan

The prevalence of Parascaris equorum in paddock horses, donkeys, and mules (n = 150 for each) of the Mona Remount Depot, Sargodha, Pakistan, was examined and the efficacy of two treatments, doramectin and garlic, measured on the basis of fecal egg counts. Parascaris equorum infection was found in 54 (36%) horses, 47 (31%) donkeys, and 42 (28%) mules. The final efficacy of treatment with doramectin was 92.5% in horses, 80.6% in donkeys, and 81.4% in mules, compared to 44.4%, 51,6%, and 37%, respectively, with garlic, making doramectin the more effective treatment.     

Survey of equine cutaneous neoplasia in the Pacific Northwest.

A retrospective study examined data regarding equine cutaneous and mucocutaneous neoplasms submitted to the Veterinary Diagnostic Laboratory at Oregon State University in a 3.5-year period. A total of 536 neoplasms were identified, accounting for 30% of the total equine pathology submissions. Sarcoid, squamous cell carcinoma, melanocytic tumors, papillomas, and mast cell tumors were the most common neoplasms, constituting 87.5% of all cutaneous neoplasms. Sarcoids represented 51.4% of all neoplasms and 15.18% of total equine accessions. Sarcoid was most common in paints, quarter horses, and Arabians, and was the only common tumor in donkeys and mules. Mean age at diagnosis of equine sarcoid was 9 years. Squamous cell carcinoma constituted 18.3% of all neoplasms and 5.41% of total equine accessions. Ocular squamous cell carcinoma was most common in paints and quarter horses, and penile/preputial squamous cell carcinoma was most common in appaloosas and quarter horses. The mean age of horses with ocular squamous cell carcinoma (13 years) and squamous cell carcinoma of the skin (15 years) was significantly less (P < 0.5) than that of horses with squamous cell carcinoma of the penis and prepuce (21 years) or vulva, anal, and perianal skin (19 years). Findings suggest that equine sarcoid and squamous cell carcinoma occur more frequently in the Pacific Northwest than in the northeastern United States.     

Lungworms (Dictyocaulus arnfieldi): prevalence in live equids in Kentucky

Prevalence of natural infections of the lungworm, Dictyocaulus arnfieldi, was investigated in Kentucky in 5,437 live equids (horses, ponies, and asses) on 91 farms by examination of fecal samples over a 15-month-period from January 28, 1983 to April 19, 1984. For the 91 farms investigated, asses only were examined on 1 farm; for the other 90 farms, examinations were made of horses on all of them, of ponies on 4 farms, and of asses on 9 farms. Larvae of D arnfieldi were found in fecal samples of 112 (2%) of 5,379 horses on the 90 farms of which 38% had greater than or equal to 1 infected animal; none of 19 ponies examined was infected. For 39 asses (donkeys and mules) examined, 21 (54%) were infected; infected asses were present on 80% of the 10 farms on which they were examined. The equids, excluding asses, that were examined and the percentage (in parentheses) infected with D arnfieldi included 4,329 (2%) Thoroughbreds, 684 (2%) Standardbreds, 78 (0%) American Saddle Horses, and 307 (3%) miscellaneous (other breeds or mixed breeds of horses and ponies). Equids were separated into 3 categories relative to previous treatment with ivermectin: A (no treatment), B (treatment), and C (treatment unknown).(ABSTRACT TRUNCATED AT 250 WORDS)     

Expression of a transforming gene (E5) of bovine papillomavirus in sarcoids obtained from horses

OBJECTIVE: To determine expression of a transforming gene (E5) of bovine papillomavirus in sarcoids, other tumors, and normal skin samples collected from horses with and without sarcoids. SAMPLE POPULATION: 23 sarcoids and 6 samples of normal skin obtained from 16 horses with sarcoids, 2 samples of normal skin and 2 papillomas obtained from horses without sarcoids, and 1 papilloma obtained from a cow. PROCEDURE: Protein was extracted from tissue samples collected from horses and incubated with agarose beads covalently coupled to Staphylococcus aureus protein A and an anti-E5 polyclonal antibody. Following incubation, proteins were eluted from the beads and electrophoresed on a 14% polyacrylamide gel and transferred to a polyvinylidene difluoride membrane. The E5 protein was detected by use of western blot analysis, using a chemiluminescence detection system. RESULTS: All 23 sarcoids had positive results for expression of E5 protein. Quantity of viral protein appeared to vary among sarcoids. All other tissues examined had negative results for E5 protein. Highest expression for E5 protein was observed in biologically aggressive fibroblastic variants of sarcoids, compared with expression in quiescent tumors. CONCLUSIONS AND CLINICAL RELEVANCE: This study documented that activation and expression of the E5 gene is evident in sarcoids obtained from horses. These data support the conclusion that infection with bovine papillomavirus is important in the initiation or progression of sarcoids in horses. Treatment strategies designed to increase immune recognition of virally infected cells are warranted.     

Equine influenza 1987, post-epidemic serological study in north india

A post-epidemic (equine influenza) serological study of different regions of the Punjab State and Chandigarh (Union Territory) was undertaken. One hundred and fifty serum samples were collected from horses, ponies, mules and donkeys and examined in haemagglutination inhibition tests. The results indicated that 87.5% to 100% had antibodies to A/equi-1 virus and 61.9 to 88.6% to A/equi-2 virus. Evidently, both the serotypes were widely prevalent during the epidemic throughout the Punjab State and Chandigarh. The involvement of both serotypes of equine influenza virus in the same population was unusual.     

Anaesthesia and analgesia of the donkey and the mule

The number of donkeys and mules throughout the world is stable, and awareness of their use and concern for welfare, pain recognition and treatment are receiving increasing veterinary interest. Therefore, accurate information about anaesthesia and analgesia in donkeys and mules is important to ever more equine practitioners. Since donkeys are physiologically and pharmacologically different from horses, knowledge on species specific aspects of anaesthesia and analgesia are very important. Mules combine elements from both donkey and horse backgrounds, leading to great diversity in size, temperament and body type. Physiologically, they seem to resemble horses more than donkeys. This review highlights the current knowledge on various anaesthetic and analgesic approaches in donkeys and mules. There is still much information that is not available about donkeys; in many circumstances, the clinician must use available equine information to treat the patient, while monitoring carefully to observe for differences in response to therapy compared to the horse.     

GRANULOMATOUS AND NEOPLASTIC DISEASES OF THE SKIN OF HORSES

Lesions encountered in a clinicopathological study of cutaneous lesions resembling 'swamp cancer' from horses in North Queensland included 37 cases of subcutaneous phycomycosis, 5 of which were also infected with Habronema sp larvae. In addition 9 cases of primary cutaneous habronemiasis, 58 sarcoids, 12 fibromas, 8 fibrosarcomas, 10 squamous cell carcinomas, 4 haemangiomas, 3 melanomas, 1 papilloma, 1 palpebral adenocarcinoma and 7 cases of simple granulation were diagnosed. Subcutaneous phycomycosis resulted in the most extensive lesions. These were rapidly growing and provided the poorest prognosis of all conditions studied. The incidence of phycomycosis in north Queensland was high in comparison to more temperate areas and appeared to be related to the wetter seasons. Young horses were more commonly affected. A fungus isolated from 3 phycomycotic lesions was tentatively identified as Hyphomyces destruens as no sporulation was observed.