The severity of pulmonary thromboembolism and pulmonary hypertension induced by heartworms dying after administration of 2 adulticides was evaluated. Because melarsomine dihydrochloride (RM340) has been shown to be more effective in killing Dirofilaria immitis (heartworms) than the traditional approved adulticide, thiacetarsamide, an attempt was made to determine whether this new adulticide induced more severe lung disease. Before adulticide treatment, 32 dogs with naturally acquired heartworm infections received physical examinations, semiquantitative antigen concentration tests, CBC, platelet counts, serum biochemistry analyses, arterial blood gas determinations, thoracic radiography, pulmonary arteriography, and pulmonary hemodynamic tests. Eight dogs with a low burden and 9 dogs with a high burden of heartworms were treated with thiacetarsamide, and 7 dogs with a low burden and 8 dogs with a high burden were treated with RM340. Except for the heartworm-burden test, tests were repeated at regular intervals during the first 7 weeks after treatment. None of the dogs coughed or had dyspnea after treatment. Six of 9 dogs with high worm burdens and 4 of 8 dogs with low worm burdens had surviving heartworms after thiacetarsamide treatment, in contrast to only 3 of 15 RM340-treated dogs. Differences between the 2 adulticide treatments were minimal as determined by thoracic radiography, pulmonary hemodynamic tests, clinical laboratory analyses, pulmonary arteriography, or necropsy. The RM340 treatment was a more effective adulticide, but it did not increase the severity of hypertension and thromboembolism.

Fifteen 2-week-old kittens were randomly assigned to 1 of 3 milk treatment groups as the sole source of nutrition for 4 weeks: queen's milk, commercially available kitten milk replacer (CMR), and an experimental milk replacer (EXP). Kittens fed queen's milk suckled ad libitum, whereas CMR- and EXP-fed kittens were tube-fed every 6 hours. Kittens were weaned at 6 weeks of age and were fed a feline growth diet ad libitum for an additional 4 weeks. Kittens were examined at 2, 4, 6, 8 and 10 weeks of age; the procedure included an ophthalmic examination and blood sample collection for CBC and serum biochemical and amino acid analyses. Kittens fed CMR and EXP diets had weight gain greater than that for queen's milk-fed kittens. The kittens fed CMR, however, had diarrhea throughout most of the milk-feeding trial and developed diffuse anterior and posterior lens opacification and vacuolation at the posterior Y-sutures. The lens opacities noticed in the kittens during the milk treatments resolved to a residual perinuclear halo, and a few incipient cortical opacities were observed by the end of the growth diet-feeding period. Serum arginine concentration was significantly (P < 0.05) lower in the CMR-fed kittens, but was not different during the growth diet-feeding period. We concluded that the EXP diet supported normal growth in 2- to 6-week-old kittens; CMR supported normal kitten growth rate, but resulted in diarrhea and cataract formation; and serum amino acid data indicated that low arginine concentration may have been related to the CMR-induced cataract formation.

Saline (0.9% NaCl) solution or 1 of 3 nonsteroidal anti-inflammatory drugs (NSAID) was administered IV to 5 neonatal calves 15 minutes after the start of a 3-hour IV infusion of Escherichia coli lipopolysaccharide (LPS; 2 micrograms/kg/h). Four additional calves were given a 3-hour IV infusion of saline solution alone. Clinical attitude, mean arterial blood pressure, PCV, WBC, and plasma lactate, glucose, and eicosanoid concentrations (thromboxane B2, 6-keto-PGF(1 alpha)) were monitored for 12 hours. Flunixin meglumine (1.1 mg/kg of body weight, IV), ketoprofen (2.2 mg/kg, IV), and ketorolac tromethamine (1.1 mg/kg, IV) each ameliorated the clinical signs of endotoxemia and LPS-induced lacticemia, but failed to significantly alter the degree of leukopenia or hypoglycemia associated with infusion of LPS. Although the 3 NSAID prevented eicosanoid production, they provided only partial protection against LPS-induced hypotension. Each NSAID modified the response to LPS, but none was clearly superior to the others in modulating the clinical signs or physiologic alterations induced by infusion of LPS in neonatal calves.

The effects of preanesthetic medication on ease of duodenal endoscopic intubation in dogs was evaluated. One of 12 combinations of preanesthetic medications (using atropine, glycopyrrolate, morphine, meperidine, acepromazine, and 0.9% NaCl solution) was administered IM to each of 12 dogs in a trial. Twelve endoscopic trials were performed so that each dog received each treatment combination once. Anesthesia was induced with thiamylal administered IV and maintained with halothane vaporized in oxygen. Electrocardiographic recordings, indirect blood pressure measurements, end-tidal carbon dioxide partial pressures, and halothane concentrations were monitored during the anesthetic period. The ease with which the fiberoptic endoscope was passed into the proximal portion of the duodenum was qualitatively scored on the basis of time and maneuvering effort. None of the preanesthetic combinations made intubation of the duodenum significantly easier than that with 0.9% Nacl solution (control). Only the combination of morphine and atropine induced gastropyloric conditions that resulted in significantly higher (more difficult) endoscopic scores than those after preanesthetic medication with 0.9% NaCl solution.

Rectal swab specimens were collected from 362 apparently healthy dogs of different origin, age, breed, and sex. Specimens were obtained in summer, autumn, and winter. Ninety-five thermophilic Campylobacter spp were isolated: C jejuni biotype I, n = 57, C jejuni biotype II, n = 1, C coli, n = 36, and C laridis, n = 1. Biotypes of C jejuni recovered were the same as those associated with Campylobacter-induced enteritis in human beings. Prevalence of C jejuni was significantly (P < 0.05) greater: in dogs < 6 months old than in adult dogs; in dogs living under high density and cohabitation housing conditions for long periods; and in autumn.

In 6 anesthetized ponies, 3 segments of jejunum and 3 segments of small colon were isolated from the peritoneal cavity in plastic bags filled with Hanks' balanced salt solution. One jejunal and 1 small colon segment were subjected to venous strangulation obstruction for 3 hours (VSO-3), venous strangulation obstruction for 6 hours (VSO-6), or a 6-hour sham procedure to control for changes induced by isolation in a plastic bag. Additional segments of jejunum and colon that were not placed in bags served as controls for histologic examination and collagenase measurements. Samples of fluid surrounding the intestine were obtained for chemical analyses, nucleated cell count, aerobic and anaerobic bacteriologic culture, and measurement of collagenase activity. Full-thickness tissue samples were obtained for histologic examination and measurement of collagenase content. Bacteria did not cross the intestinal wall after 3 and 6 hours of VSO, despite severe mucosal lesions in these segments. At 6 hours, P(O2) was significantly less and P(CO2) was significantly (P < 0.05) greater in the fluid surrounding the VSO-6 jejunal segments, compared with the sham jejunal segments. The pH was significantly (P < 0.05) less in fluid surrounding VSO-6 small colon segments, compared with the sham colon segments at 6 hours. For jejunum and small colon, phosphate and lactate concentrations were significantly (P < 0.05) greater in VSO-6 fluid than in the corresponding sham fluids at 6 hours. Fibrin formed around all VSO segments, although fibrinogen was not detected in the surrounding fluid, indicating possible rapid conversion of fibrinogen to fibrin. Fluid collagenase activity increased significantly (P < 0.05) in all segments over 6 hours. The preparation used in this study was successful in measuring local changes on the serosal surface of intestine subjected to VSO and in isolating segments under study in a sterile environment.

Five cows in the last month of gestation, provided with uterine electrodes and in which catheters had been chronically installed in the fetal aorta, were used to study patterns of fetal heart rate (FHR) and the influence of periods of myometrial electrical activity during gestation (contractures) on FHR. The FHR was calculated by counting the number of blood pressure pulses on the tracings during alternate periods of 12 seconds. Three 1-hour recordings without contractures and 10 recordings during the time of a contracture were randomly selected for each cow. The calculated data points were plotted on a graph to display FHR patterns. In 41 periods associated with single contractures, FHR data points were taken every 72 seconds. Changes in absolute and relative FHR in these periods were determined to analyze a possible effect of contractures on FHR. Three types of variation in FHR patterns could be distinguished: a short-term, low-amplitude variation of basal FHR; a second type in which the duration was < 4 minutes and the amplitude was greater than or equal to 15 beats/min; and prolonged periods with increased or decreased FHR values (> 4 minutes and greater than or equal to 15 beats/min). The relationship between these types of variation and fetal activity states remains to be established for cows. During the 60 hours of recordings that were analyzed, a period of several minutes during which FHR values were extremely high (> 180 beats/min) was found 3 times. There were no significant differences in absolute or relative FHR before, during, or after a contracture.

An agar gel immunodiffusion (AGID) test was used over a 3-year period to examine 1,871 serum samples from sheep representing 5 Mycobacterium paratuberculosis infected flocks and 4 flocks presumed to be uninfected. Of 1,032 sheep, 31 had positive AGID test results (scoring 1 to 5), and 23 of these 31 were ecropsied. Infection with M paratuberculosis was confirmed by 1 or more of the following findings: observation of typical lesions on histologic examination of sections of ileum or ileocecal lymph nodes, observation of clumps of acid-fast bacteria in mucosal smears of ileum, and isolation of the organism from feces or tissue. False-positive results on AGID testing were not found in sheep from flocks known to have exposure to Cotynebacterium pseudotuberculosis. Diarrhea in infected sheep was observed infrequency; chronic, severe weight loss was the most common sign observed. On histologic examination of tissues from 20 infected sheep, 16 (80%) had diffuse lesions of the ileum and 13 (65%) had acid-fast bacteria in areas of ileal inflammation; 4 had discrete granulomas and peripheral lymphocytic infiltrates in the ileum. Sheep with diffuse lesions tended to have higher mean scores on AGID testing and examination for acid-fast bacteria, compared with those from sheep with more discrete lesions. Bacteriologic culture yielded M paratuberculosis from only 3 sheep with paratuberculosis. On the basis of results of this study, we suggest that the nature of the response to infection with M paratuberculosis may influence the results of diagnostic tests for paratuberculosis, and that AGID testing may be useful to identify M paratuberculosis infection in sheep with chronic weight loss and in flock-screening programs.

After IV administration of 0.5 mg of glucagon/cat, glucose tolerance and insulin secretory response were evaluated in 10 lean cats, 10 obese cats, and 30 cats with diabetes mellitus. Blood samples for glucose and insulin determinations were collected immediately before and at 5, 10, 15, 30, 45, and 60 minutes after IV administration of glucagon. Baseline serum insulin concentration and insulin secretory response were used to classify diabetes mellitus in the 30 cats as type I or type II. Mean (+/- SEM) baseline and 30-minute serum glucose concentrations in obese cats were significantly (P < 0.05) decreased, compared with values in lean cats, but were similar at all other blood sample collection times. Serum glucose concentration in diabetic cats was significantly (P < 0.05) greater than values in obese and lean cats at all blood sample collection times. Two statistically different insulin responses to IV administration of glucagon were seen in diabetic cats. Of the 30 diabetic cats, 23 had minimal insulin secretory response after glucagon administration (ie, serum insulin concentration was at or below sensitivity of the insulin assay). Seven diabetic cats had baseline serum insulin concentration similar to that of obese cats and significantly (P < 0.05) greater than that of lean cats and of the other 23 diabetic cats. In these 7 diabetic cats, serum insulin concentration increased after glucagon administration. Total insulin secretion was not significantly different between these 7 diabetic cats and the lean and obese cats, and was significantly (P < 0.05) greater than total insulin secretion in the other 23 diabetic cats. Results support existence of type-I and type-II diabetes mellitus in cats.

Desoxycorticosterone pivalate was administered IM to juvenile Beagles at 0, 2.2, 6.6, or 11 mg/kg of body weight daily over a consecutive 3-day period every 28 days (equivalent to a cumulative monthly dosage of 0, 6.6, 19.8, or 33 mg/kg) for 6 months. Polyuria, polydipsia, and decreases in serum potassium and BUN concentrations were detected while the dogs were being treated. Transient increases in serum sodium concentrations also were detected. The treated males had significant decreases in body weight gain, resulting in an 18% decrease in body weight in the 11-mg/kg dosage group, compared with the controls. The weights of the adrenal glands, epididymides, and testes also were lower in the treated males. Organ weights for the 2.2, 6.6, and 11-mg/kg dosage groups were: 86, 79, and 69%, respectively, of the controls (adrenal glands); 80, 70, and 68%, respectively, of the controls (epididymides); and, 79, 75, and 67%, respectively, of the controls (testes). When normalized to body weight, these decreases in organ weight were still dosage-dependent, but the differences were less remarkable. In contrast, the relative weight (to body weight) of the kidneys (males and females) and of the thyroid and parathyroid glands (males) were higher dosage-dependently. All of the treatment-related effects, other than organ and body weight changes, appeared to be reversible following the cessation of treatment. On the basis of these results, it was concluded that treatment with desoxycorticosterone pivalate could be tolerated, even when given at dosages 15-fold the therapeutic dosage of 2.2 mg/kg every 25 days.