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CASE DESCRIPTION An 8-year-old Brahman-cross bull was evaluated for left hind limb lameness of 2 months' duration. The lameness was first noticed during a rodeo bucking performance, immediately after the bull appeared to land inappropriately on the affected limb. CLINICAL FINDINGS Physical examination findings revealed left hind limb lameness, ataxia, and left-sided epaxial muscle atrophy. Palpation per rectum along the lumbar portion of the vertebral column revealed evidence of exostosis of the ventral aspect. High-definition infrared thermal imaging revealed a pattern of reduced skin temperature in the area of the left lumbar and gluteal regions suggestive of a disruption in the sympathetic control of peripheral blood flow. Nuclear scintigraphy revealed a focal area of increased radioisotope uptake on the left ventrolateral aspect of the L2-3 intervertebral joint. A presumptive diagnosis of ventrolateral vertebral spondylosis resulting in spinal nerve impingement was made. TREATMENT AND OUTCOME 200 mg of methylprednisolone was epidurally injected at the site of the lesion, and treatment with polysulfated glycosaminoglycans was initiated (500 mg, IM, every 4 days for 7 treatments, then monthly thereafter). The lameness and ataxia observed in the left hind limb resolved within 1 week after treatment began. Subsequently, the bull was discharged from the hospital and was used successfully for semen collection and live-cover breeding. CLINICAL RELEVANCE Use of thermography for the bull of this report provided additional insight into neurovascular physiologic function that classical imaging modalities are unable to provide and, when combined with nuclear scintigraphy, aided in identifying the most critical lesion in a complex clinical case.

Competing Interests: There are no conflicts of interest.

Aim: To study management and maternal and fetal outcome in single fetal death in twin pregnancies., Materials and Methods: We studied 64 (1.37 %) twin deliveries out of a total of 4,655 deliveries in GMC, Haldwani (Uttrakhand). Out of them, 5 (7.81 %) were complicated with single fetal death in the second or third trimester. These cases were managed conservatively with regular monitoring of maternal coagulation profile along with intensive fetal surveillance for the surviving twin. The cases were studied for antenatal complications and placental chorionicity with placental histopathology and postmortem of the dead fetus. Neonatal and maternal outcome in the postpartum period was also studied., Results: No antenatal complications were present in four out of five cases with one having PIH. Three out of five pregnancies could be extended to term and had no maternal complications. The other fetus could be salvaged in three and all of them had a normal neonatal period. One pregnancy ended in preterm labor with delivery of a preterm baby which could not be saved. One resulted in death of the other fetus also where pregnancy was remote from term., Conclusions: Although our study was small, it indicates that in case of twin pregnancy with single fetal death with good surveillance, the live fetus can be salvaged.

Signet ring cell carcinoma of the ampulla of Vater is extremely rare. The 7 cases reported earlier have been in older patients. We report a 32-year-old lady with this condition, who also had metastases in the bone marrow, vertebrae, lungs and liver.

Lipomas of the small intestine are usually found incidentally; symptoms occur in less than one-third of affected patients, especially when lipomas are more than 2 cm in size. We report a 32-year-old man in whom intestinal lipomatosis resulted in colo-colic intussusception. These symptoms disappeared following operative resection of about 60 cm of ileum and ascending colon.

Evaluation of the reproductive function of Lama glama is generally considered to be a challenging task due to the difficulty of obtaining representative semen samples. One method that has been proposed for evaluation of testicular function in these animals is histologic examination of testicular needle biopsies. This study was undertaken to examine the safety and efficacy of using needle biopsies to assess testicular function in this species. One randomly selected testicle from each of 16 sexually mature llamas was biopsied with a 14-gauge self-firing biopsy instrument. The llamas were evaluated over a 6-week period with thermography for temperature changes of the scrotum. At the end of the 6-week trial, the llamas were castrated and sections of each testis were fixed in Bouin's solution for histologic examination. Immediately prior to castration, an additional biopsy was taken from each testis to compare the tissue obtained via biopsy with sections from the corresponding testis obtained after castration. A qualitative grading scale was used to compare the seminiferous tubules from each testis. No difference was found between the biopsied and the nonbiopsied testes (P = 0.69). The percentage of normal tubules between the biopsied and the nonbiopsied sides also did not differ (P = 0.70). Furthermore, the percentage of normal seminiferous tubules did not differ between the needle biopsy samples and the corresponding tissue samples obtained at castration (P = 0.48). The number of round seminiferous tubules counted in each biopsy section ranged from 3 to 67. There was no significant difference in the thermographic images of the scrotum between the biopsied and the nonbiopsied testes. This study supports testicular biopsies as a safe and useful procedure in the evaluation of testicular function.

Objective: To determine whether testicular needle biopsy is detrimental to testicular function in clinically normal bulls., Design: Prospective study., Animals: 6 mixed-breed mature bulls., Procedure: A randomly selected testicle from each bull was biopsied with a 14-gauge needle biopsy instrument. Bulls were then evaluated over a 90-day period for changes in scrotal temperature and thermal patterns, ultrasonographic appearance, and quality of spermatozoa. At the end of the 90-day study, bulls were castrated, and testicles were examined grossly and histologically., Results: Changes were detected in scrotal temperatures and thermal patterns and in the breeding soundness examination results during the first 2 weeks of the study. However, there were no long-term changes in semen quality over the course of the experiment. Hyperechoic areas were detected on ultrasonographic examination and corresponded to the areas of penetration by the biopsy instrument. Microscopic lesions that were indicative of testicular dysfunction were not found., Conclusions and Clinical Relevance: Results indicate that testicular biopsy is a safe procedure in bulls. Testicular biopsy could possibly be used to further examine bulls that have less than satisfactory results for breeding soundness examinations.

The objective of this research was to determine if whole-body shearing would effect gross thermoregulation in alpacas. Eight mature, intact male alpacas were randomly assigned to one of two groups and maintained in outdoor pastures with adequate artificial shade from June through August (summer climate) in east central Alabama, USA. Group one animals (N=4) were sheared to remove all fiber to within 2cm of their skin. Group 2 animals (N=4) were left non-sheared. Sheared alpacas tended to have lower rectal temperatures during high ambient temperatures than did non-sheared alpacas (P=0.06). Thermographic studies of the scrotum revealed cooler surface temperatures in sheared versus non-sheared alpacas (P=0.05). Temperatures in the right medial thigh of sheared animals were 0.9 degrees C cooler than the thigh region of non-sheared animals in the morning (P<0.03). Right medial thigh temperatures were 1.6 degrees C cooler in sheared alpacas in the afternoon (P<0.01). Significant positive correlations were found in non-sheared animals between ambient temperature and rectal temperature in the morning (r=0.612, P=0.014). In sheared animals during the morning significant positive correlations were established between the Heat Stress Index (HSI) and the right medial thigh surface temperatures (r=0.648, P=0.003), the HSI and rectal temperature (r=0.729, P=0.0003), the ambient temperature and right medial thigh surface temperature (r=0.485, P=0.04), and the ambient temperature and the rectal temperature (r=0.823, P<0.0001). In the afternoon a significant positive correlation was found in the sheared alpacas between the HSI and the right medial thigh surface temperature, rectal temperature and surface scrotal temperature (r=0.538, P=0.02, r=0.543, P=0.019 and r=0.522, P=0.045), respectively. These data indicate that whole-body shearing of alpacas could have a beneficial effect on thermoregulation when used as a preventative measure against heat stress. Shearing may assist heat dissipation resulting in a cooler surface body temperature and rectal temperature in alpacas when challenged by the heat and humidity experienced in the summer months in the southeastern United States.

Bulls and bucks were used to study the blood flow into and out of the corpus cavernosum penis (CCP) during the non-erect state of the penis. When contrast medium was injected into the dorsal artery of the penis in a bull cadaver and into surgically implanted catheters of anesthetized bucks, it flowed into the cavernous spaces of the CCP via the penetrating arteries. When contrast medium was injected directly into the CCP of the bull and buck there was no evidence of vascular exits along the body of the penis. The only venous outlets from the CCP were in the crus penis area. In the non-erect penis the vascular pressure within the CCP was 17.8 mm Hg higher in the bull and 8.3 mm Hg higher in the buck at the glans area than the crus area. During the non-erect state of the penis most of the blood flow to the CCP is from the dorsal artery of the penis via the penetrating arteries. The results showed that the pressure gradient provides the means for flow of blood from the glans area toward the base or crus penis area. This flow prevents platelet aggregation and clot formation and provides nutrition to local tissue during the long periods of non-erection.

Objective: This study evaluates the clinical usefulness and anesthetic effect of propofol, and compares these effects with those of xylazine-ketamine-halothane anesthesia in sheep., Study Design: Prospective, randomized, clinical trial., Animals or Sample Population: Fourteen healthy adult male sheep., Methods: Sheep were randomly assigned to two different drug regimens: (1) Bolus injection of propofol (3 mg/kg, intravenously [i.v.]) followed by continuous intravenous infusion and (2) xylazine (0.11 mg/kg, i.v.) and ketamine (2.2 mg/kg, i.v.) for induction followed by halothane anesthesia. Heart rate, respiratory rate, and arterial blood pressures were monitored during anesthesia. Venous blood samples were collected for blood gas analysis. Quality of induction and recovery were also recorded., Results: The average dose of propofol used to induce and maintain anesthesia was 6.63 +/- 2.06 mg/kg and 29.3 +/- 11.7 mg/kg/hr (0.49 +/- 0.20 mg/kg/min), respectively. The duration of propofol anesthesia was 45.3 +/- 13.2 minutes and recovery to standing occurred in 14.7 +/- 5.7 minutes. Sheep receiving xylazine-ketamine-halothane were anesthetized for 35.9 +/- 4.0 minutes and recovery to standing occurred within 28.5 +/- 7.5 minutes. Sheep anesthetized with propofol had a significantly higher heart rate, diastolic blood pressure and Pvo2, and a lower Pvco2 at 30 minutes and lower BE at 15 and 30 minutes than sheep anesthetized with xylazine-ketamine-halothane., Conclusions: Propofol anesthesia was characterized by a smooth induction, effective surgical anesthesia and rapid recovery which was comparable to anesthesia with xylazine-ketamine-halothane., Clinical Relevance: Propofol may be indicated in situations when it is desirable to maintain anesthesia with an intravenous infusion followed by a rapid recovery in healthy sheep.

Objectives: To use lipopolysaccharide (LPS) to create synovitis in the midcarpal joint of ponies, and to assess the morphologic, histochemical, and immunohistochemical effects of synovitis on articular cartilage of the third carpal bone., Animals: 2- to 3-year-old ponies, 6 control (group 1) and 6 treated (group 2)., Procedure: Synovitis was induced in 1 midcarpal joint of group-2 ponies by intra-articular injections of LPS (0.02 micrograms/kg of body weight), morphine (0.1 mg/kg), and saline solution (group 2a) and a morphine and saline solution alone in the contralateral midcarpal joint (group 2b). Articular cartilage sections and attached synovial membrane from the third carpal bones were examined by immunohistochemical distribution of interleukin 1 beta, tumor necrosis factor (TNF)-alpha, TNF receptors (P55, P75) and 3-B-3(-) epitopes, and by localization of proteoglycans (metachromatic staining). Proteoglycan extracts were assessed by metachromatic staining or western blotting and immunohistochemical staining, using anti-3-B- antibodies., Results: Enhanced immunoreactivity for the cytokines and receptors was found in inflamed synovial membrane and noncalcified cartilage (group 2a more than 2b). Metachromasia of the noncalcified cartilage was greater in group-1 than in group-2a and group-2b specimens. In group 2a, chondrocyte hypertrophy and enhanced immunoreactivity for 3-B-3(-) epitope in areas of increased cytokine immunoreactivity suggested possible phenotypic change of the chondrocytes in response to synovitis. Immunohistochemical analysis by western blotting of proteoglycan extracts indicated strong 3-B-3(-) epitope immunolocalization in group-2a, weaker staining in group-2b, and barely detectable stain in group-1 specimens, which correlated with in situ immunolocalization., Conclusions: Intra-articular administration of LPS may be used to induce a synovial environment conductive to increased immunoreactivity of interleukin 1 beta, TNF-alpha, and its receptors in equine synovial membrane and articular cartilage. These cytokines may be involved in the early phenotypic change of chondrocytes that is believed to occur in osteoarthritis and is characterized in this study by enhanced 3-B-3(-) epitope immunoreactivity and chondrocyte hypertrophy.

The aim of the present investigation was to check the fluctuation in essential elements, such as Na, K, Mg, Mn, Cu, Zn, Cr and Ni in the brain, spinal cord, liver and kidney of mice during methylmercury chloride (MMC) toxication and therapy with monothiols (N-acetyl-DL-homocysteine thiolactone and glutathione) and vitamins (vitamin B complex and E). Mercury deposition and its elimination during chelation therapy were also screened for comparative purposes. The animals were dosed for 7 days with MMC 1 mg/kg/d and some were then kept without treatment for a further. 7 days. Other MMC-treated animals were immediately given one of the above antidotes for 7 days. All the animals were sacrificed on the 15th day. There was a decrease in all elements during MMC toxication with few exceptions, for example, copper was increased in the liver as was sodium in the kidney. Treatment with the thiols and vitamins restored the levels of these elements in certain tissues towards normal, but their concentrations remained abnormal in most instances. The fluctuations in the concentration of these elements were attributed to their association with various macromolecules.

Mean conduction velocity of sensory axons of the dorsal penile nerves of clinically normal bulls was determined by recording action potentials evoked by cutaneous stimulation. Locations of stimulating and recording electrodes were standardized. Overall mean +/- SD conduction velocity was 55.1 +/- 5.1 m/s. Mean +/- SD velocity recorded from the distal electrode was 53.3 +/- 4.9 m/s; velocity recorded from the middle electrode was 55.3 +/- 5.0 m/s; and velocity recorded from the proximal electrode was 56.7 +/- 5.1 m/s. Differences among means were not significant. Four bulls had mean conduction velocities of 54.0 m/s and 48.4 m/s before and 3 weeks after castration, respectively.

A native African bull was examined for ataxia of 10 days' duration. Clinical signs included bradycardia, ataxia, hypermetria, and dysphonia. Cerebrospinal creatine kinase activity was high. Thermographic evidence of bilateral accessory nerve dysfunction was observed. This finding was supported by electromyographic studies. Survey and positive contrast radiographs were nondiagnostic. Clinical signs exacerbated after radiographic examination. Treatment included dexamethasone and flunixin meglumine administered IV.

Equine amnion and live yeast cell derivative were evaluated as a biological dressing and as a topical wound medicament respectively, in the treatment of granulating wounds of the distal portion of the limbs of horses. Wounds measuring 2.5 x 2.5 cm were created on the dorsomedial aspect of the metacarpal and metatarsal region of all 4 limbs of 9 horses. Each wound was assigned randomly to 1 of 3 treatment groups: group C, treated with a nonadherent bandage as a control; group A, treated with amnion beneath a nonadherent bandage; and group L, treated with live yeast cell derivative beneath a nonadherent bandage. Rates of contraction and epithelialization were not significantly different among groups. Percentage of epithelialization for group A was significantly greater throughout the study than for the other groups. Number of days to complete healing was significantly less in group A and significantly greater in group L than in group C. Incidence and severity of exuberant granulation tissue were significantly less in group A than in the other 2 groups. Group L had more frequent and severe cases of exuberant granulation tissue than the other 2 groups.

The carotid artery of clinically normal goats was examined, using duplex ultrasonography and arteriography. The diameter of the carotid artery was measured by use of two-dimensional ultrasonography and Doppler ultrasonography, respectively, before and after xylazine administration. The diameter of the artery was also measured by use of an arteriography technique in halothane-anesthetized goats. There was no significant difference between the mean diameter of the carotid artery measured by ultrasonography in conscious nonsedated goats and that determined by arteriography in goats under halothane anesthesia. On the other hand, ultrasonography of xylazine-sedated goats revealed an increase of carotid artery diameter of 20 to 30%. There was no change in the velocity of blood flow after xylazine administration.

To establish a clinically practical procedure for recording the equine EEG, 25 healthy adult horses and 6 newborn foals were used. Recordings were taken with the animals alert and tranquilized, confined in metal stocks, or physically restrained. The dominant alert waveforms of adult horses were fast activity (25 to 40 Hz) with medium-to-low voltages (5 to 40 microV-dominant 10 to 15 microV). Underlying this fast activity was slower (0.5 to 4.0 Hz) activity with medium-to-low voltages (10 to 40 microV). Twelve of the 25 adult horses had EEG frequencies in the alpha frequency range (10 to 15 Hz, 10 to 50 microV). Eight horses were given xylazine and 17 were given acetylpromazine. Those given xylazine had generalized slowing with several distinct frequency patterns (25 to 40 Hz, 5 to 30 microV; 10 to 15 Hz, 10 to 80 microV; and 0.5 to 4.0 Hz, 10 to 90 microV). Horses given acetylpromazine had fast activity (25 to 40 Hz) with medium-to-low voltages (5 to 40 microV). Underlying this activity were slower waveforms (1 to 4 Hz) with medium-to-low voltages (5 to 10 microV). Occasional well-formed spindle activity was observed (10 to 14 Hz, 10 to 50 microV). Acetylpromazine had little effect on the EEG recording, whereas xylazine exerted a substantial effect. All leads were synchronous with lower voltages in the left frontal, right frontal, and transfrontal leads. The alert pattern of a newborn foal was characterized by low frequency (2 to 6 Hz) with medium-to-high voltages (20 to 90 microV).(ABSTRACT TRUNCATED AT 250 WORDS)

A continuous series of electroencephalograms (EEG) was obtained from each of 6 mature horses which had been given xylazine and ketamine hydrochloride IV. Electrocardiograms and respiratory rates were also obtained. The EEG of the unsedated standing adult horse displayed a dominant fast activity in the range of 25-35 Hz, 5-30 microV superimposed over slower 1-4 Hz, 10-50 microV activity with occasional 10-14 Hz, 10-40 microV spindle-type activity. The xylazine-sedated horse displayed hypersynchronous EEG patterns, with the dominant activity being 1-3 Hz, 10-70 microV with overlying mixed frequencies of 5-10 Hz, 10-40 microV and 10-14 Hz, 10-40 microV spindle-type activity. Some 25-35 Hz, 5-10 microV activity was present in 5 of the 6 horses. Ketamine administration 3 minutes after xylazine injection caused an increase in high-voltage slow activity. The dominant frequency was 1-3 Hz, 20-100 microV, with superimposed mixed irregular frequencies of 6-10 Hz, 10-50 microV and 10-14 Hz, 10-40 microV spindle-type activity. All horses developed some degree of second-degree atrioventricular (AV) heart block approximately 23 s after xylazine was injected. The second-degree AV heart block disappeared approximately 1 minute and 30 s after ketamine was injected in 4 of the 6 horses. The remaining 2 had second-degree AV heart block throughout the recording period (15 to 18 minutes). Respiration rates were depressed after xylazine was given and became irregular and apneustic after ketamine injection. The cyclic rate of respiration varied from 19 to 30 breaths/minute. Xylazine depressed heart rates from 13% to 41% (mean 29.3%). Heart rates became faster or remained unchanged after ketamine was administered.

Thermographic and radiographic evaluations of the tarsus (hock) were done on 20 Standardbred racehorses before and after exercise at three consecutive 6-week intervals. All horses were from the same stable and given the same care and training under identical schedules and conditions. Normal thermographic patterns were established before and after exercise. These patterns corresponded to the underlying tarsal vasculature. Postexercise thermal patterns indicated a warming trend, and the increases were uniform. Abnormal thermal patterns were more localized and did not conform to the normal underlying vascular distribution. Five of the 20 horses trained successfully and competed professionally, with 1 of the 5 showing abnormal thermographic changes. Four horses were too slow to race, and all of these had abnormal thermographic changes of their tarsi. The medial aspect of the right tarsus was more commonly involved than the lateral in these horses. Only one horse was clinically lame and exhibited thermal increases, as well as radiographic changes in the right tarsus. The remaining horses were removed from training due to miscellaneous causes. It was believed that the four horses that failed to make minimum track times (for racing) suffered discomfort in their tarsi sufficient to impair performance. This problem was attributed to early subclinical inflammatory changes within the joints. Though difficult to recognize radiographically, these early changes were conspicuous as abnormal thermographic patterns typical of inflammation.

Two cases of sex cord tumour of the ovary with annular tubules were diagnosed in African females of 23 and 57 years. In one case it was associated with the Peutz-Jeghers syndrome and with Stein-Leventhal ovaries whilst in the other case, pigmentation of the oral mucosa was present but without demonstrable polyposis of the intestine. The patient with the Peutz-Jeghers syndrome presented with primary sterility whilst the other patient had a normal menstrual and obstetric history. Signs of virilization were not found in either case. The previously reported literature is reviewed and discussed.

The vascular anatomy of the adrenal glands and a surgical technique for bilateral adrenalectomy in the equid are described. Bilateral adrenalectomy was performed in six ponies and one horse via bilateral transcostal retroperitoneal approaches through the 18th rib during a single anesthetic period. Complications included hemorrhage from the right side only and pneumothorax which usually occurred on the right side. One pony died as a result of the surgical technique. Maintenance of adrenal function was accomplished with desoxycorticosterone pivilate and prednisolone.

Six ponies and 1 horse were bilaterally adrenalectomized (BADX). The survival time of 2 of the 7 animals after BADX was 24 and 72 hours without supplemental corticosteroids. The cause of death was not related to the surgical technique. The biological half-life of cortisol (hydrocortisone) was estimated to be 2.1 +/- 0.6 hours. The disappearance of cortisol in the horse was found to be biphasic, composed of redistribution and elimination phases. Pathophysiologic changes (ie, increased serum sodium and chloride, increased PCV, and decreased serum potassium) similar to those seen in other species after BADX were found. Clearance of electrolytes was calculated, using the creatinine clearance method. These values were inversely correlated with the changes seen in serum electrolytes.

To evaluate the use of thermography in equine medicine, a three-phase study was conducted. In the first phase, six horses were examined thermographically, before and after exercise, to determine a normal thermal pattern. In the second phase, nine horses with acute and chronic inflammatory processes were examined thermographically. In the third phase, thermography was used to evaluate the effectiveness of anti-inflammatory drugs on chemically induced inflammatory reactions. All normal horses tested had similar infrared emission patterns. There was a high degree of symmetry between right and left and between front (dorsal) to rear (palmar, plantar) in the legs distal to the carpus and the tarsus. The warmer areas of the thermogram tended to follow major vascular structures. The coronary band was the warmest area of the leg. Heat increase due to exercise did not substantially alter the normal thermographic pattern. Use of thermography in clinical cases successfully detected a subluxation of the third lumbar vertebra, a subsolar abscess, alveolar periostitis and abscess, laminitis, serous arthritis of the femoropatellar joint, and tendonitis. Thermography was effective in quantitative and qualitative evaluation of anti-inflammatory compounds in the treatment of chemically induced inflammation.

A needle-tipped catheter or subminiature pressure transducer was implanted in the corpus spongiosum penis (CSP) of Shetland Pony stallions to determine pressure during coitus. Electrodes for monitoring the electromyographic (EMG) activity were implanted in the ischiocavernosus (IC) and bulbospongiosus (BS) muscles. The mean peak CSP pressure recorded with the catheter was 762 mm of Hg, and with the subminiature pressure transducer, it was 994 mm of Hg. The simultaneous occurrence of the CSP pressure peaks and bursts of BS muscle activity indicated that these muscles were the likely source of energy for the increased pressures, which were far greater than the systemic blood pressure. This conclusion was further supported by the finding that anesthesia of the BS muscles greatly reduced the CSP pressures of the stallion during attempted coitus.

Thermographic patterns of the bovine scrotum were established in 15 clinically normal bulls and were compared with patterns in 10 bulls with scrotal and testicular diseases. Thermography of a normal scrotum was characterized by a symmetrical and constant thermal pattern with a temperature gradient of 4 degrees to 6 degrees (C) from the base to the apex of the scrotum. There was a significant difference (P less than 0.05) in the temperature from the base to the apex of the scrotum (34.94 +/- 0.60 C to 30.11 +/- 0.91 C). Lack of thermal symmetry was seen in bulls with unilateral lesions. Inflammation of one testicle increased ipsilateral scrotal infrared emission temperature 2.5 degrees to 3 degrees (C) above that in the contralateral side. If both testes were inflamed and hyperemic, there was an overall increase in scrotal temperature of at least 3 degrees (C), and a reduction in temperature gradient of 2 to 3 degrees (C) from the base to the apex of the scrotum. Area temperatures in bulls with chronic testicular degeneration with fibrosis were reduced.

The pharmacokinetics of gentamicin were studied in six healthy mature horses of mixed breeding and of both sexes. A parenteral preparation of gentamicin sulfate (5% aqueous solution) was administered rapidly (IV) at the dosage level of 5 mg/kg of body weight. Venous blood samples were taken at 0 (base line), 0.083, 0.25, 0.5, 0.75, 1, 2, 4, 8, 12, 24, 36, 48, 72, 96, and 120 hours after gentamicin administration. Serum gentamicin was measured by a radioimmunoassay technique. The gentamicin concentration data was fitted to a one- and two-compartment open model with first-order elimination from the central compartment with the aid of nonlinear least squares program. The data were found to be best described by the two-compartment model with r2 = 0.997. Half-life, as determined from the terminal phase was 2.54 +/- 0.33 hours. Calculation of the total body clearance provided a mean of 1.16 +/- 0.11 ml/minute/kg of body weight (1.04 to 1.31 ml/minute/kg, range); the volume of distribution calculated from the area under the curve was determined separately for each animal and had a mean value of 0.254 +/- 0.036 L/kg. The initial exponential decline (alpha) in gentamicin serum concentration had an average value of 3.75 +/- 1.86 hours-1, whereas the terminal values were described by beta = 0.275 +/- 0.036 hours-1. Other pharmacokinetic values determined also are presented.

Lateral and frontal thermographic patterns of the head of normal horses before and after exercise were characterized to aid the diagnosis of diseases of the head. Surgical induction of Horner's syndrome was done in four horses by isolation and transection of the vagosympathetic trunk. One clinical case and the surgically induced cases of Horner's syndrome were evaluated clinically. Thermographic findings of the clinical case were similar to the experimental cases.

Three ponies and 1 horse were bilaterally adrenalectomized (BADX). The initial hypoadrenal episode after BADX was reversed with 20 mg of dexamethasone (DXM) IM (n = 2) or 20 mg of triamcinolone (TMC) IM (n = 2). Nine hypoadrenal crises were reversed with 20 mg of DXM given IM (n = 4) or 20 mg of TMC given IM (n = 5). Sodium and chloride retention and potassium excretion were documented based on changes in serum electrolytes and urinary excretion. Eight intact adult horses were randomly assigned to 2 groups to study the effects of a single IM injection of DXM (0.044 mg/kg of body weight) or TMC (0.044 mg/kg). Cortisol (hydrocortisone) suppression was found to be maximal (nondetectable amounts of cortisol) by 12 hours in both groups. Cortisol was again detectable in the DXM group at 24 hours after injection and was at pretreatment values at 168 hours. Cortisol was not detectable in the TMC group for 192 hours and did not reach pretreatment values until 336 hours. The duration of the gluconeogenic effect was compared with the duration of cortisol suppression exerted by DXM and TMC in these intact animals. Assuming that the decrease in plasma glucose coincides with the decrease in glucocorticoid activity of the respective steroid, a relative hypoadrenocortical state was found in the animals treated with DXM between the 2nd and 7th day after treatment, whereas this state occurred between the 6th and 14th day after treatment with TMC.

This study evaluated the pony as a potentially suitable model for vascular implant research. Healthy, conditioned ponies were randomly assigned to one of three groups: group I, carotid artery autografts (n = 6); group II, e-PTFE carotid interpositional grafts (n = 5); and group III, e-PTFE carotid interpositional grafts plus aspirin (10 mg/kg) and dipyridamole (3.5 mg/kg) drug administration. It was found that autografts remained patent longest (mean = 396.2 days; grafts were still patent at time of writing) followed by group III grafts (157.5 days), with group II grafts remaining patent for the shortest duration (61.1 days), (p less than 0.01). Patency was determined using two-dimensional real-time ultrasonography with Doppler velocimetry and/or arteriography. It was demonstrated that the pony's response to antithrombotic drugs was consistent and comparable to that in other animal models, both with respect to platelet function and affect on patency rate. The combination of the ease of surgical manipulation, drug administration, and platelet function testing, the comparable size of the pony and its heart and blood vessels to that of an adult human, the long life span of ponies, and the patency results of this study have demonstrated that the pony is a valuable animal model for vascular research.

Circulating concentrations of angiotensin I and plasma renin activity (PRA) were determined in 45 Thoroughbreds before prerace medication (at rest), 1 to 1 1/2 hours before racing but after prerace medication (prerace), within 15 minutes after racing (immediately postrace), and between 1 to 2 hours after racing. Angiotensin I was measured by radioimmunoassay, and PRA was determined by the rate of generation of angiotensin I in plasma incubated at 37 C. Irrespective of prerace medication, there was a marked increase in angiotensin I (0.478 +/- 0.034 to 0.848 +/- 0.051 ng/ml) and PRA (0.191 +/- 0.018 to 0.522 +/- 0.061 ng/hour/ml) from the at-rest samples to the immediate-postrace samples, with the exception of anhidrotic horses in which increases in angiotensin I (0.7131 +/- 0.0794 to 0.8081 +/- 0.0608 ng/ml) and PRA (0.1635 +/- 0.0379 to 0.2176 +/- 0.0437 ng/hour/ml) were not as marked as they were in other horses. Administration of 1 mg of furosemide/kg 2 hours before racing caused an increase in PRA from 0.2438 +/- 0.0324 to 0.3706 +/- 0.1110 ng/hour/ml, whereas horses under the influence of 4 mg of phenylbutazone/kg had a decrease in PRA from 0.2090 +/- 0.0440 to 0.0669 +/- 0.0206 ng/hour/ml. Marked increases in angiotensin I and in PRA did not occur when horses were administered furosemide and phenylbutazone as prerace medication.

Unilateral orchiectomy was performed on 9 mature mixed-breed bulls with satisfactory semen quality to study the effect of the procedure on quality of semen from the contralateral testicle. Semen was collected by electroejaculation before surgery and on alternate days for 2 weeks, then once weekly for 8 weeks. Each sampling day, progressive motility and morphologic features of spermatozoa were determined, and scrotal thermograms were taken. The percentage of normal spermatozoa decreased significantly (P less than 0.05) only on postoperative day 6. Progressive motility scores varied but at the end of the study there was no significant difference from preoperative values. Scrotal thermography revealed inflammation in the contralateral side of the scrotum, beginning 3 days after surgery, but the thermograms were normal in most bulls by 3 weeks after surgery, and all thermograms were normal by 4 weeks.

Total strangulation obstruction of the caudal part of the jejunum was induced in 3 groups (each of 3 ponies) for 2, 4, and 6 hours. Coagulation tests which included blood platelet counts, prothrombin time, activated partial thromboplastin time, activated coagulation time, plasma fibrinogen level, and fibrin/fibrinogen degradation products assay were performed at specified time intervals for 1 week or until death of the experimental ponies. Another 3 ponies (sham-operated) were similarly treated, except that intestinal strangulation obstruction (ISO) was not induced. Necropsy was done on ponies that were euthanatized 9 days after the sampling period and on 2 ponies that died. Six hours of ISO resulted in severe ischemic damage to the intestines, characterized by hemorrhagic infarction, with or without perforation, in ponies that died, and total loss of mucosa with moderate to severe fibrosis of the intestinal wall in the surviving pony of this group. This damage was associated with significant coagulopathies, notably prolonged prothrombin time and activated partial thromboplastin time, decreased blood platelets count, and the presence of high levels of fibrin/fibrinogen degradation products (40 micrograms/ml). These laboratory findings are indicative of disseminated intravascular coagulation. In contrast, the jejunal segments of the ponies subjected to 2 and 4 hours of ISO were viable as revealed by histopathologic examination. There were no significant changes found in their coagulation profiles.(ABSTRACT TRUNCATED AT 250 WORDS)

At Port Moresby General Hospital a retrospective analysis of 305 deaths that occurred between 1976 and 1980 following trauma was conducted. As road traffic accident fatalities made up 56% of all fatalities a more detailed analysis of the different factors involved in such accidents was made. Results show that 82% of the victims of road traffic accidents fatalities were below 35 years of age and that 57% of fatal accidents occurred during the period Friday to Sunday. Evidence of recent alcohol consumption was found in 85% of drivers involved in accidents. Eighteen out of 20 pedestrians tested had also been drinking alcohol. The overall incidence of head injuries was 65.5%. Chest injury was seen in 51% of cases. Sixty-six per cent of the victims died either at the site of the accident or before any effective treatment could be offered. Among the non-road traffic accident fatalities 21% of subjects with blunt and sharp penetrating injuries had a blood alcohol level exceeding 80 mg per 100 ml. Several measures have been recommended to prevent or to reduce the incidence of traumatic deaths in this country.