Cardiopulmonary consequences of IV administered glycopyrrolate (0.01 mg/kg of body weight), followed in 11 +/- 2 minutes by butorphanol (0.2 mg/ kg) and xylazine (0.5 mg/kg), were evaluated in 6 dogs, with and without nasal administration of oxygen (100 ml/kg/min). Glycopyrrolate caused significant (P < 0.05) increases in heart rate and cardiac index and significant (P < 0.05) decreases in stroke index. Subsequent administration of butorphanol and xylazine was associated with significant (P < 0.05) increases in systemic vascular resistance, mean arterial blood pressure, mean pulmonary artery pressure, central venous pressure, pulmonary capillary wedge pressure, PaCO2, venous admixture, oxygen extraction ratio, and hemoglobin concentration. It caused significant (P < 0.05) decreases in cardiac index, stroke index, breathing rate, minute volume index, oxygen delivery, and oxygen consumption. Mean arterial blood pressure, pulmonary vascular resistance, tidal volume index, and minute volume index were significantly (P < 0.05) higher when dogs were breathing room air. The arterial and venous PO2, and PCO2, and venous oxygen content were significantly (P < 0.05) higher, and the arterial and venous pH, and oxygen consumption were significantly (P < 0.05) lower when oxygen was administered. Pulsus alternans and S-T segment depression were observed in dogs of both groups. Ventricular premature contractions were observed in 1 dog breathing room air. All dogs were intubated briefly 15 minutes after administration of butorphanol and xylazine. Time to first spontaneous movement was 45 minutes. All dogs remained in lateral recumbency without physical restraint for 60 minutes.

The effect of mimicking prepartum concentration of estradiol-17 beta on the inflammatory response to endotoxin in gilts was studied. The study was performed in a split-litter design and comprised 5 pairs of littermates. A catheter was inserted into the jugular vein 2 days prior to the start of the study. In each pair, 1 littermate was treated IM with 2.5 mg of estradiol-17 beta/75 kg of body weight, and the other littermate was given peanut oil IM as a control. The day after treatment, all gilts were challenge-exposed with a Salmonella typhimurium-derived endotoxin (1 microgram/kg, IV) and the inflammatory response to challenge exposure was monitored. There was no effect of estradiol treatment on the transient clinical signs of endotoxemia or on the increase in rectal temperature. The increase in blood concentrations of prostaglandin F2 alpha, metabolite and cortisol after endotoxin challenge exposure was not affected by estradiol. Decrease in number of circulating blood mononuclear cells and polymorphonuclear leukocytes was not changed by estradiol treatment. Taken together, mimicking prepartum concentration of estradiol did not affect either the magnitude or the kinetics of the inflammatory response to endotoxin in gilts. Relevance of these findings to development of endotoxin-mediated diseases, such as the postpartum agalactia syndrome, needs further study.

Temporal changes, as well as differences in distribution, in concentrations of 24 amino acids in plasma and whole blood of neonatal foals were determined from birth to 2 days of age. In addition, differences in concentrations of amino acids in plasma between mare and foal pairs were determined at birth. Significant (P < 0.05) hypoaminoacidemia existed for 15 amino acids in plasma of foals at birth, compared with mares (paired t-test). Concentrations of 7 amino acids (aspartate, glutamate, glutamine, glycine, hydroxyproline, phenylalanine, proline) in plasma of foals were higher (P < 0.05) at birth than in mares, and concentrations of 2 (taurine, tryptophan) were not different (P > 0.05). Significant (P < 0.05) temporal changes for concentrations of 19 of 24 amino acids in plasma were observed during the 48-hour period. Concentrations of 13 of the 19 amino acids in plasma that had significant changes were higher (P < 0.05) at 48 hours. Significant (P > 0.05) effect of time on concentration of 5 amino acids (alanine, methionine, phenylalanine, taurine, threonine) in plasma was not found after birth. Temporal changes in concentrations of 7 amino acids (alanine, asparagine, glutamine, histidine, hydroxyproline, methionine, and threonine) in whole blood were not significantly (P > 0.05) different from those in plasma. Temporal changes for concentrations of the remaining 17 amino acids in whole blood were significantly (P < 0.05) different, compared with plasma. Distribution of the concentrations of 18 amino acids between whole blood and plasma was significantly (P < 0.05) different. Concentrations of 5 amino acids (citrulline, cystine, glutamine, methionine, tryptophan) were significantly (P < 0.05) lower in whole blood than in plasma, whereas concentrations of 13 amino acids were significantly (P < 0.05) higher in whole blood vs plasma. Concentrations of 6 amino acids (asparagine, isoleucine, leucine, proline, serine, valine) in whole blood were not significantly different from concentrations in plasma. Significant differences in temporal patterns of concentrations of amino acids in plasma and whole blood may be attributable to nutritional or physiologic changes associated with parturition. Significant differences between concentrations of amino acids in whole blood and plasma may be attributable to ontogeny or specificity of transport systems across cell membranes.

An applanation tonometer was used to estimate intraocular pressure in normal eyes of several species of raptors. No bird had active injury or illness, though some were nonreleasable to the wild because of previous injury. Mean (+/- SD) intraocular pressure was 20.6 (+/- 3.4) mm of Hg in red-tailed hawks (Buteo jamaicensis, n = 10), 20.8 (+/- 2.3) mm of Hg in Swainson's hawks (Buteo swainsoni, n = 6), 21.5 (+/- 3.0) mm of Hg in golden eagles (Aquila chrysaetos, n = 7), 20.6 (+/- 2.0) mm of Hg in bald eagles (Haliaeetus leucocephalus, n = 3), and 10.8 (+/- 3.6) mm of Hg in great horned owls (Bubo virginianus, n = 6). There was no significant difference in intraocular pressure between hawks and eagles. Mean pressure in great horned owls was significantly (P < 0.01) lower than pressure in hawks or eagles. Reliable intraocular pressure readings could not be obtained in barn owls (Tyto alba).

Effects of endotoxemia on left ventricular contractility and systemic hemodynamics were determined in pentobarbital-anesthetized swine. A multielectrode conductance (volume) catheter and a high-fidelity pressure transducer catheter were passed retrograde into the left ventricle to continuously measure pressure and volume. End-systolic pressure-volume relationships were determined during transient (8 to 10 s) caudal vena caval balloon occlusion. Lactated Ringer's solution was administered at a rate sufficient to maintain left ventricular end-diastolic pressure > 6 mm of Hg. Following baseline measurements, Escherichia coli endotoxin (O55-B5) was infused IV at 2.5 micrograms/kg of body weight/h for 3 hours. Left ventricular end-systolic elastance (Ees), the slope of the end-systolic pressure-volume relationship; end-systolic elastance normalized for left ventricular end-diastolic volume (Ees norm); the rate of increase of left ventricular pressure (dP/dtmax); and preload recruitable stroke work (PRSW, stroke work-to-end-diastolic volume relationship) did not change in endotoxemic swine, compared with baseline measurements or with values from control (physiologic saline solution-treated) swine. Left ventricular pressures and volumes had marked pig-to-pig variability in the control and endotoxin-treated groups. Determination of Ees, Ees norm, and PRSW was further confounded by development of frequent premature ventricular contractions during caudal vena caval balloon occlusion. Endotoxin significantly (P < 0.05) decreased left ventricular end-diastolic pressure, compared with that in control swine, and significantly (P < 0.01) decreased left ventricular end-diastolic volume, compared with baseline. Endotoxin decreased cardiac index and arterial blood pressure, whereas heart rate, central venous pressure, and mean pulmonary arterial pressure increased. Endotoxin did not decrease myocardial contractility, as measured by Ees, Ees norm, dP/dtmax, or PRSW in anesthetized swine.

Once daily for 3 days, laser Doppler flowmetry was used in 5 healthy, nonsedated adult horses to evaluate coronary band and laminar microcirculatory blood flow (MBF) in both forelimbs, The coronary band had significantly (P < 0.05) higher MBF than did the laminae on the days evaluated. Significant variation in MBF was not found over the 3-day measurement period in any one site. Significant (P < 0.05) variation was found in coronary band MBF among horses. This variation was not observed in laminar MBF. On occlusion of the digital arteries at the level of the fetlock, marked decrease in coronary band and laminar MBF was observed. Twenty minutes after IV administration of acetylpromazine, marked increase in coronary band and laminar MBF was observed. The technique was easily performed in standing nonsedated horses, did not inflict discomfort, lacked complications, and measurements were repeatable. This technique provides an index of digital MBF, either intermittently or continuously, avoiding introduction of invasive variables associated with other techniques.

Platelet function, antithrombin and plasminogen activities, and fibrinolytic capabilities in 11 cats with acquired heart disease were compared with results in 4 healthy cats. Of 11 cats with heart disease, 9 had hyperthyroidism with secondary cardiac dysfunction. One cat with hyperthyroidism had renal disease and heart failure, and of 2 cats with idiopathic hypertrophic cardiomyopathy, 1 also had renal disease. At the time of testing, 3 cats had thromboembolic events associated with the disease. Compared with healthy cats, cats with acquired heart disease had increased activity of antithrombin III, a protein that behaves as an acute-phase reactant. Plasminogen activity was decreased, although not significantly, in cats with acquired heart disease, compared with results in healthy cats. In cats with left ventricular dysfunction, clot retraction was decreased (marginal significance, P = 0.058) and might be attributed, in some cases, to the medications received by the cats. Dilute whole blood clots from all cats failed to lyse in vitro. This observation, at present, lacks adequate explanation. Platelets from cats with acquired heart disease, compared with platelets from healthy cats, had decreased responsiveness (aggregation and [(14)C]serotonin release) to adenosine diphosphate and increased responsiveness to collagen. Hyperthyroid cats were receiving various drugs (propranolol, atenolol, or diltiazem) to empirically treat clinical signs of disease attributable to cardiac dysfunction. Although numbers of cats in each group were small, definite trends were observed in the results of tests. Platelets from cats receiving atenolol had decreased responsiveness to adenosine diphosphate and unaltered responsiveness to collagen, compared with platelets from healthy cats, and may have decreased risk of thrombus formation. Cats receiving propranolol and diltiazem had platelets with markedly increased responsiveness to collagen; however, these drugs appeared to provide sufficient cardioprotective benefits to counter the prothrombotic effects.

The microscopic brush border membrane adherence assay was used to determine resistance (nonadherence) and susceptibility adherence) of Chinese pigs (n = 289) to the K88ac+ strain of Escherichia coli-mediated disease. This study estimates prevalence of resistance to diarrheal disease in multiple family lines (no common ancestry for a minimum of 3 generations) for the Chinese Meishan, Fengjing, and Minzhu breeds. Results of in vitro assays indicate that pigs of the Meishan breed are highly resistant (nonadherent) to K88ac+ E coli-mediated disease. The gene conferring susceptibility to K88ac+ E coli-mediated disease exists at low frequency in pigs of the Minzhu breed. Minzhu-type (crossbred) pigs of both phenotypes (susceptible and resistant) were identified in ratios consistent with a 1-locus gene model. Given that all susceptible pigs were from 1 site, frequency of susceptibility within this Minzhu population is estimated at 8%. Inheritance within the Fengjing breed is still unclear because a weakly adherent phenotype, as well as the resistant phenotype, was identified. The weakly adherent phenotype was observed in pigs derived from multiple family lines. Expression of the weakly adherent phenotype in terms of susceptibility to disease is not known at this time.

Venous access devices connected to jugular vein catheters were implanted SC in 2 groups of 6 White Carneau pigeons (Columba livia). Total parenteral nutrition (TPN), or a control solution (lactated Ringer's solution) was infused as a bolus 4 times daily. Physiologic, hematologic, and biochemical variables were monitored over 5 days. Complications in the TPN-treated pigeons included 8.7% weight loss during the 5-day trial, hyperglycemia for up to 90 minutes after infusion, and glucosuria after infusion. Control pigeons lost 1.3% of their body weight and did not become hyperglycemic or glucosuric after infusion. Hematocrit in both groups of pigeons decreased to a value slightly below published reference values for pigeons. Five pigeons developed venous thrombosis in the proximal part of the cranial vena cava. Results indicated that intermittent administration of TPN is possible in birds; however, further research is required to develop better techniques for administration of TPN solutions. Additionally, it is important to determine, more specifically, the caloric and nutrient requirements of pigeons under stress and receiving TPN.

Results of testing of 19,731 samples from a serologic survey of cattle with bluetongue virus (BTV) infections in Australia were analyzed for association between age, species, or sex and test result. Bivariate analysis indicated that all 3 host factors were associated with test result. After adjusting for confounding caused by the location of each animal in the study (high, moderate, and low BTV prevalence regions), cattle greater than or equal to 4 years old had an odds ratio of 4.33 (95% confidence interval, 3.99, 4.71) for a positive test result, compared with that for cattle < 2 years old. Cattle 2 to 4 years had an odds ratio of 2.28 (2.14, 2.54), compared with cattle < 2 years old. Bos taurus cattle had an odds ratio of 1.76 (1.63, 2.05) of a positive test result, compared with crossbred cattle, and B indicus cattle had an odds ratio of 1.20 (1.09, 1.33), compared with crossbred cattle. Sexually intact (+) male cattle were found to have an odds ratio of 3.13 (2.66, 3.49) for a positive test result, compared with castrated male (-) cattle, and female cattle were found to have an odds ratio of 1.38 (1.29, 1.48), compared with male (-) cattle. Multivariate analysis of BTV testing results was performed, using stepwise logistic regression. The most parsimonious model selected included age, species, and sex factors, and first-order interaction terms between these factors. This model was only able to be fit to data from cattle restricted to the high (> 25%) BTV prevalence region. Odds ratios were found to increase with age for male (-) cattle of all species. Odds ratios were found to be greatest at 2 to 4 years of age for female cattle of all species and for B taurus and crossbred male (+) cattle.