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Ionophores are widely used in veterinary medicine as coccidiostats and for improving nutrient utilization in livestock production. Because of widespread use, ionophores sometimes cause poisoning in livestock. Quantifying concentration of these compounds in feeds for diagnostic purposes is needed. A method with a single step of solvent extraction was developed for rapid simultaneous quantification of monensin, lasalocid, salinomycin, and narasin in feeds by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The ionophores were extracted using methanol:water (90:10). With the high specificity and high sensitivity of tandem mass spectrometry, the extract was introduced for measurement without further processing. The effect of particle size of feeds on extraction efficiency was also investigated. It was found that feeds passing through a 1-mm filter or sieve show better quantitative extraction. Nigericin was used as internal standard for the measurement. The method was validated by fortification of the selected ionophore compounds in horse feed at different concentrations. The typical recovery rate was 69-122%. Meanwhile, various interlaboratory proficiency test samples of different matrices were also quantified as part of the procedure for method validation. A good agreement was found between results and the suggested values. The method is very sensitive, with detection limits between 0.018 µg/g and 0.056 µg/g for the compounds tested. Results showed that the lower limit of quantification was 0.2 µg/g for the ionophore compounds, which is much lower than the contents of the ionophores in medicated feeds, which is generally approximately 10-100 µg/g feed.

Two of three captive adult African ostriches exhibited inappetance and weakness. In spite of treatment, the two birds were euthanized because of lack of clinical improvement. Postmortem examination demonstrated exocrine pancreatic degeneration, necrosis, and atrophy. Grossly, one ostrich had a markedly diminished pancreatic mass. Histologically, there was massive pancreatic acinar (exocrine) atrophy, marked interstitial fibrosis, and tubular complex formation in one animal, and the second ostrich had active pancreatic acinar necrosis. Toxicologic testing revealed markedly elevated liver zinc levels in the first two birds, whereas the third ostrich had normal serum levels of zinc and continues without apparent disease. This form of zinc toxicosis, while previously reported in different avian species, has been only rarely described in ratites.

Veterinary diagnostic laboratories are constantly required to be innovative to develop quick, reliable, and cost-effective methods for use in diagnosis of intoxications. Livestock intoxication with ionophore antibiotics is sometimes encountered. A rapid qualitative method based on liquid chromatography-tandem mass spectrometry was developed to screen for the presence of monensin, lasalocid, salinomycin, and narasin antibiotics in feeds. This new method has high specificity and high sensitivity, and yet minimum sample preparation was employed. The analytes were extracted in methanol-water (9010) and analyzed without further purification. Because the test uses a single extraction procedure and no cleanup is necessary, its turnaround time is 4 hr. The method applies the concept of "identification points" (IP) score to identify suspected ionophore antibiotics. The total IP score used to identify each of the ionophore antibiotics by this method was 7.0, which exceeds the minimum score of 4.0 required for acceptable identification of unknown compounds. The specificity of the method was achieved using retention time and multiple reaction monitoring with a total IP score of 7.0.

Abstract: Plasma clearance of iohexol was evaluated in eight anesthetized California sea lions (Zalophus californianus), without evidence of renal dysfunction, to determine if the one-compartment model and the sample protocol used in dogs and cats could be applied to this species. Nonlinearity between samples in 75% (6/8) of sea lions voided those results. An additional two anesthetized sea lions were sampled at 5, 30, 45, 60, 120, 180, 240, and 360 min post iohexol injection and semi-logarithmic curves calculated. Plasma iohexol clearance values calculated by one-, two-, and noncompartment models were in poor agreement, suggesting that the standardized protocol described for dogs and cats cannot simply be applied to California sea lions, probably due to the effects of the dive reflex induced during anesthesia.

As part of ongoing ecological studies of Humboldt penguins (Spheniscus humboldti) at Punta San Juan, Ica Department, Peru, health surveys were conducted in November 1992, 1993, and 1994. In the three surveys, 98 birds in total were handled for examination, and blood was collected for laboratory analysis from 90 of these birds. All birds seemed to be in good condition. Body weights of females were significantly lower in 1994 than in the other years. Fleas (Parapsyllus humboldti) and ticks (Ornithodoros amblus) were found on the penguins and in their nests. Females had significantly higher plasma calcium and phosphorus levels, and they had lower weights than males. No other differences were found between the sexes. Hematology, plasma chemistries, and plasma mineral levels varied between years. Positive antibody titers for Chlamydophila psittaci (62%), avian adenovirus (7%; 1994 only), paramyxovirus-2 (7%; 1993 only), and Salmonella Pullorum (7%) were found. Plasma chemistry and mineral levels differed between individuals testing positive vs. negative on serologic tests for avian adenovirus and Salmonella Pullorum. Serologic tests for antibodies to avian influenza A virus, avian encephalomyelitis virus, infectious bronchitis virus, avian reovirus, duck viral enteritis virus, equine encephalitis (eastern, western, and Venezuelan) viruses, infectious bursal disease virus, infectious laryngotracheitis virus, Aspergillus sp., and paramyxovirus-1 and -3 were negative. All chlorinated pesticide and polychlorinated biphenyl analyses were below detectable limits.

Diagnostic evaluation of a mildly ataxic young gelding Quarterhorse included a contrast myelogram. Unfortunately, sodium diatrizoate was inappropriately administered by intrathecal injection resulting in severe unrelenting seizure activity and necessitated the destruction of the animal. The contrast agent was identified by analyzing cerebrospinal fluid by high-performance liquid chromatography and confirmed with probe mass spectrometric analysis. This contrast agent is highly ionic, has high osmolarity, and also blocks neurotransmission at specific receptors; for these reasons it is contraindicated for use in myelography. This is the first report of intrathecal administration of this agent in a horse, although there has been a previous report of similar untoward reactions in a dog, and numerous cases have been reported in humans.

Objective: To determine whether pharmacokinetic analysis of data derived from a single i.v. dose of iohexol could be used to predict creatinine clearance and evaluate simplified methods for predicting serum clearance of iohexol with data derived from 2 or 3 blood samples in clinically normal foals., Animals: 10 healthy foals., Procedure: Serum disposition of iohexol and exogenous creatinine clearance was determined simultaneously in each foal (5 males and 5 females). A 3-compartment model of iohexol serum disposition was selected via standard methods. Iohexol clearance calculated from the model was compared with creatinine clearance. Separate limited-sample models were created with various combinations of sample times from the terminal slope of the plasma versus time profile for iohexol. Correction factors were determined for the limited-sample models, and iohexol clearance calculated via each method was compared with exogenous creatinine clearance by use of method comparison techniques., Results: Mean exogenous creatinine clearance was 2.17 mL/min/kg. The disposition of iohexol was best described by a 3-compartment open model. Mean clearance value for iohexol was 2.15 mL/min/kg and was not significantly different from mean creatinine clearance. A method for predicting serum iohexol clearance based on a 2-sample protocol (3- and 4-hour samples) was developed., Conclusions and Clinical Relevance: Iohexol clearance can be used to predict exogenous creatinine clearance and can be determined from 2 blood samples taken after i.v. injection of iohexol. Appropriate correction factors for adult horses and horses with abnormal glomerular filtration rate need to be determined.

In conjunction with reproductive and feeding ecology studies on southern giant petrels (SGP, Macronectes giganteus) blood samples were collected for baseline health evaluations. Twenty-five adult SGP from a breeding colony in Chubut, Argentina, were sampled during two consecutive breeding seasons, 1999-2000 (n = 15) and 2000-01 (n = 10). Values for hematology, plasma biochemistry, and minerals are described for 20 birds in apparent good physical condition. A serologic survey of exposure to selected infectious agents was also conducted on all 25 birds sampled. Southern giant petrels were serologically negative for evidence of exposure to infectious laryngotracheitis virus, avian encephalomyelitis virus, avian influenza virus, avian reovirus, infectious bursal disease virus, infectious bronchitis virus, paramyxovirus 1, 2, and 3 virus, Chlamydophila, and Aspergillus. Antibodies to avian adenovirus were found in 14% of SGP during the first sampling season, and 60% in the second year. Additionally, all birds were negative for antibodies to Salmonella pullorum at the first sampling date, but 90% had low titers the following breeding season. This study contributes to understanding the health status of South Atlantic seabirds and to establishment of baseline information for SGP. Long-term monitoring of pelagic predator-scavenger seabirds such as SGP should be established for the surveillance of marine ecosystem health.

Acute onset convulsive disorders in the canine may result from exposure to a variety of toxicants including strychnine, insecticides, metaldehyde, zinc phosphide, methylxanthines, drugs of abuse, bromethalin, and the tremorgenic mycotoxins (roquefortine and penitrem A). Although several of the above can be identified in a single gas chromatography-mass spectrometry (GC-MS) screen most have to be determined by separate tests. This report describes a modification of the strychnine extraction procedure, which allows thin layer chromatographic (TLC) identification of strychnine, bromethalin, roquefortine, and penitrem A in suspect baits, stomach contents or vomitus, and extends the identification to a wide variety of drugs, pesticides, and environmental contaminants by GC-MS. Samples were mixed with base, extracted into CH2Cl2 and the organic fraction back-extracted with acid. The organic fraction (neutrals) was purified by gel permeation chromatography (GPC) and analyzed by TLC to determine penitrem A and bromethalin. The acidic aqueous fraction was adjusted to pH > 9 and extracted into CH2Cl2. The resulting CH2Cl2 layer (bases) was then analyzed by TLC to determine strychnine and roquefortine. The organic basic and neutral fractions were recombined with a late eluting GPC fraction and analyzed by GC-MS. Of 312 samples analyzed by TLC from 1995 to 2001, 35 were positive for strychnine alone, 58 were positive for both roquefortine and penitrem A, 4 were positive for roquefortine alone, and 1 was positive for bromethalin. None of the samples were positive for penitrem A alone. Samples negative by TLC were analyzed by the GC-MS extended procedure since mid-1999, and 14 have shown positive for a wide variety of compounds with convulsant activity.

A 38-day-old male warthog (Phacochoerus aethiopicus) with marked anaemia (haematocrit = 14 %) presented to the Denver Zoological Gardens hospital with ataxia, tachypnoea, suspected stunted growth and cardiomegaly. The piglet demonstrated some features consistent with both iron deficiency anaemia and autoimmune haemolytic anaemia. Serum-soluble iron was below the level of detection (< 8.96 micromol/l). Iron deficiency anaemia is a well recognised entity in domestic swine reared on concrete and denied access to soil. Fifteen captive warthogs were subsequently evaluated for serum soluble iron content (mean = 21.62 +/- 4.36 micromol/l as well as 5 neonatal warthog piglets that required hand-rearing. Only 1 of 5 neonatal warthog piglets had measurable serum soluble iron (9.50 micromol/l). These data suggest that warthogs are similar to domestic swine and are born with low iron stores. Some form of iron supplementation should be considered for captive neonatal warthog piglets, especially if they are reared on concrete.

Female guinea pigs were injected intraperitoneally with 0.083 g/kg iron dextran (Fe-D) to achieve progressively increasing levels of iron load; controls received dextran. Delayed and blocked cardiac conductivity at the Purkinje fiber-papillary muscle junction was initially observed with Fe-D loads of 0.33 g/kg. Serial magnetic resonance relaxation time measurements obtained from livers of live animals showed a decrease (8.1 +/- 0.86 vs. 14.8 +/- 1.03 ms in controls, P < 0.001) that was first observed in animals loaded with 0.25 g/kg Fe-D. Iron concentrations in hearts and livers were significantly increased (P < 0.001). Left ventricular pressure measurements on 1.5 g/kg Fe-D animals failed to demonstrate a defect in contractility, but 27% (9/33) (P < 0.050) of the animals died without warning signs. We conclude that 1) initial decreases in liver magnetic resonance-relaxation time occur in the same range of iron excess as the threshold of iron load that induces delay or blockade of cardiac conduction and 2) a high incidence of sudden death, presumably from cardiac arrhythmias, was observed with large doses of iron that did not decrease left ventricular contractility.

Mercury and selenium act as mutual antagonists in mature birds, but their toxicity is additive or synergistic in avian embryos and immature birds. Twenty eggs and livers from 18 mature and 9 immature common loon carcasses found in Minnesota were collected. Livers and eggs were analyzed for mercury and selenium by atomic emission and atomic absorption spectroscopy. Liver mercury concentrations were significantly higher in mature loons compared to those of immature loons and eggs. Liver selenium concentrations were significantly higher in mature loons than those of immature loons, and selenium concentrations in immature loon livers were significantly higher than levels in eggs. There was a significant positive correlation between mercury and selenium in loon livers. There was a negative correlation between mercury and selenium in eggs.

Lead poisoning in cattle and other food animals is of public health significance because of the potential for human exposure to lead through ingestion of contaminated meat and milk products derived from lead-poisoned animals. In Michigan, lead poisoning in livestock is a reportable disease, and positive cattle are quarantined until they test negative (<0.05 ppm blood lead). There is surprisingly little information on blood lead kinetics in cattle. The half-life has been variably reported as 9 weeks and 1-2 months. Because these data did not fit those obtained from cases received at the Michigan State University Animal Health Diagnostic Laboratory, a retrospective study was conducted to review all cases of accidental lead poisoning in cattle between 1990 and 1998. This information is needed to estimate when quarantined lead-poisoned cattle can be released. The results showed that the half-life of blood lead was quite variable and ranged from 48 to 2,507 days. The shortest half-lives (48, 56, and 57 days) were found in a lactating herd of 20-month-old heifers. The longest half-life, 2,507 days, was found in a 9-month-old castrated bull, which ingested a discarded automobile battery. Of the 24 animals monitored, only 8/24 (33%) had half-lives between 6 and 14 weeks. In conclusion, the half-life of blood lead is difficult to predict in accidental cases of cattle poisoning.

The objective of this study was to determine if plasma iohexol clearance, computed by a 1-compartment model defined by 3 plasma samples. was an accurate measure of glomerular filtration rate (GFR) in dogs. Twenty-two adult Beagle dogs of both genders were studied. Ten dogs had intact kidneys, and 12 dogs had surgically reduced renal mass. A bolus injection of iohexol was made, and blood was obtained for plasma iohexol assay after 120, 180, and 240 minutes. Plasma was analyzed for iohexol concentration by means of 3 assay methods: chemical, high-performance liquid chromatography (HPLC), and inductively coupled plasma emission spectroscopy (ICP). Urinary clearance of exogenous creatinine was used to measure GFR for three 30-minute periods occurring between 150 and 240 minutes after iohexol injection. Plasma clearance of iohexol and renal clearance of creatinine were compared by linear regression analysis and by limits of agreement techniques. Plasma iohexol clearance and urinary exogenous creatinine clearance were significantly correlated (chemical R2 = .90; HPLC R2 = .96; and ICP R2 = .96). The 1-compartment iohexol clearance:exogenous creatinine clearance ratios were 1.04 +/- 0.17, 1.05 +/- 0.14, and 1.10 +/- 0.15 for the chemical, HPLC, and ICP methods of assay, respectively, indicating that plasma iohexol clearance slightly overestimated GFR. Assuming a +/- 2 standard deviation interval for error, corrected plasma iohexol clearance measured GFR with +/-34% accuracy for the chemical, +/-26% accuracy for the HPLC, and +/-27% accuracy for the ICP method. These results indicate that plasma iohexol clearance should have utility for detection of renal dysfunction earlier in the course of progressive renal disease than is possible with measurement of plasma creatinine or urea concentrations.

Animal responses are useful means of evaluating and assessing nutritional status. Blood mineral concentrations can be useful nutritional responses, although there are important limitations. The nutritional value in monitoring blood mineral concentrations varies with the specific mineral, being generally most valuable for those minerals in which homeostasis is regulated primarily by renal excretion, as opposed to regulation by variable absorptive efficiency. Examples of minerals for which blood concentrations are good measures of nutritional intake are selenium and magnesium. Blood mineral concentrations are affected by multiple variability factors. The strategy for use in mineral status assessment is to minimize non-nutritional variation by grouping animals for testing based on physiologic factors that affect, or are likely to affect, the concentration of the mineral or minerals being tested. Care should be taken to use the proper sampling protocol, so as not to cause artifactual variation. Removal of the serum from the clot within 2 hours of sample collection is an important step, among others. Sampling adequate numbers of animals and evaluating the herd mean and SD can minimize the effect of random variation on interpretation.

Objective: To quantify and compare intracellular magnesium concentrations (Mgi) in clinically normal dogs (control dogs) and dogs that have gastric dilatation-volvulus (GDV dogs) and to determine whether there is a difference in Mgi and serum magnesium concentrations (Mgs) between GDV dogs with and without cardiac arrhythmias., Animals: 41 control dogs and 21 GDV dogs., Procedure: Rectus abdominis muscle specimens were obtained from control and GDV dogs for determination of Mgi. Blood samples were obtained from GDV dogs for determination of Mgs, and dogs were monitored for 48 hours for cardiac arrhythmias. Muscle specimens were frozen at -40 C, oven dried at 95 C, and digested with concentrated nitric acid. Multielemental analyses were performed by simultaneous/sequential inductively coupled plasma-atomic emission spectroscopy with fixed-cross flow nebulization. The Mg, was standardized to sulfur content to correct for the amount of fat and fascia in the muscle specimen. Mean (+/- SEM) values were recorded in parts per million (ppm). Results-There were no significant differences in Mgi between control (627 +/- 11.1 ppm) and GDV (597 +/- 20.5 ppm) dogs, in Mgi between GDV dogs with (590 +/- 34 ppm) and without (584 +/- 29 ppm) cardiac arrhythmias, and in Mgs between GDV dogs with (1.77 +/- 0.26 ppm) and without (1.51 +/- 0.09 ppm) cardiac arrhythmias. There was no correlation between Mgs and Mgi (R2 = 0.0001)., Conclusions and Clinical Relevance: Results indicate that Mg depletion is not pathophysiologically important in dogs with GDV and does not play a role in the cardiac arrhythmias detected in these patients.

Endotoxin (lipopolysaccharide; LPS) and mercury are compounds of food safety concern. Endotoxin is a product of cell walls of gram negative bacteria. Humans are constantly exposed to LPS through infection plus translocation into circulation from the gastrointestinal tract. Food is the major source of mercury in humans. The toxic interaction between LPS and mercury has not been well investigated. In a previous study, we demonstrated that LPS potentiated mercury-induced nephrotoxicity in the rat. Whether this observation was species specific was not clear. In this study we tested the hypothesis that LPS enhances mercuric chloride (HgCl(2))-induced nephrotoxicity in mice. In a 2x2 factorial design, mice received either Escherichia coli 0128:B12 endotoxin (2.0 mg/kg body weight) or 200 microliter of 0.9% sodium chloride (saline), and this was followed 4 h later by either mercury (1.75 mg mercuric chloride per kg body weight) or 200 microliter of saline. Mice were monitored for 48 h. Monitored end-points included body and renal weights, urine volume, renal histology and ultrastructural pathology, serum urea nitrogen and creatinine, selected serum and urine cytokines, and renal mercury concentrations. Endotoxin by itself was not nephrotoxic at the dose used in this study. Overall, mice given LPS plus mercury were the most severely affected. Mice given LPS and mercury also had significantly greater renal mercury concentration than those given mercury alone (P

The objectives of this study were to develop a novel approach to postmortem diagnosis of cholecalciferol (CCF) toxicosis in dogs using kidney, bile, and urine samples, and to differentiate CCF from ethylene glycol (EG) toxicosis. To achieve these objectives, specimens collected from 2 previous laboratory studies in which dogs were given a single oral toxic dose of CCF (8.0 mg/kg) were used. For EG toxicosis, historical data from the previous 13 years (1985-1998) were reviewed and confirmed cases of EG toxicosis were selected. The historical data were used to compare trace mineral concentrations, specifically of calcium and phosphorus to differentiate between intoxications caused by CCF from that caused by EG in dogs. Kidneys, bile, and urine from dogs that died of CCF toxicosis were analyzed for 25 monohydroxy vitamin D3 (25(OH)D3) and 1,25 dihydroxy vitamin D3 (1,25(OH)2D3) and compared to known control unexposed dogs. Results of this study show that biliary and renal 25(OH)D3 concentrations and renal calcium to phosphorus ratio are of diagnostic value in dogs exposed to toxic concentrations of CCF. The renal calcium to phosphorus ratio was <0.1 in normal dogs, 0.4-0.9 in dogs that died of CCF toxicosis, and >2.5 in dogs that died of EG toxicosis.

Endotoxin (lipopolysaccharide; LPS) and mercury are nephrotoxic compounds of food safety concern. Endotoxin is a product of cell walls of gram negative bacteria. Humans are constantly exposed to LPS through food, water and air. Food is the main source of mercury exposure for humans. Endotoxin potentiates the toxicity of a number of xenobiotics, but its interaction with nephrotoxic heavy metals has not been investigated. We tested the hypothesis that endotoxin enhances mercury-induced nephrotoxicity. Thirty-two, 41-43-day-old, male Sprague-Dawley rats were allocated randomly to four groups of eight rats each as follows: group I received 0.9% sodium chloride, group II received 2.0 mg of Escherichia coli 0128:B12 LPS kg(-1) once, group III received 0.5 mg mercuric chloride kg(-1) once, and group IV received 2.0 mg E. Coli 0128:B12 LPS kg(-1) once 4 h before receiving 0.5 mg mercury chloride kg(-1) once. Mercury, LPS and 0.9% sodium chloride were all injected IV through the tail vein. Rats were monitored for 48 h after mercury injection. Serum creatinine, urea nitrogen, and polyuria were significantly increased in rats given LPS plus mercury relative to those given either agent alone or saline (P

Objective: To determine whether pamidronate disodium can reduce cholecalciferol-induced toxicosis in a dose-related manner., Animals: 20 clinically normal, 8- to 12-month-old male Beagles., Procedure: All dogs were given 8 mg of cholecalciferol (CCF)/kg of body weight once orally, then were randomly assigned to 4 groups of 5 dogs each. Dogs were treated with IV administration of 0.9% NaCl solution (SC group), 0.65 mg of pamidronate/kg in 0.9% NaCl solution (LP group), 1.3 mg of pamidronate/kg in 0.9% NaCl solution (MP group), or 2.0 mg of pamidronate/kg in 0.9% NaCl solution (HP group) on days 1 and 4 after administration of CCF. Dogs were observed for 14 days, and serial blood samples were collected for serum biochemical, electrolyte, and 25-hydroxyvitamin D3 analyses. Urine samples were collected for determination of specific gravity. Glomerular filtration rate (GFR) was determined by plasma iohexol clearance. Histologic examination of renal tissue was performed., Results: One dog in the SC group was euthanatized 3 days after administration of CCF because of severe clinical signs of toxicosis. Dogs in the HP group had significantly higher mean GFR (day 3), serum potassium concentrations (day 14), and urine specific gravity (days 7 and 14) and significantly lower mean serum creatinine concentrations and total calcium X phosphorus concentration product (days 4 and 7) than dogs in the SC group. Dogs in the HP group had no abnormal findings on histologic examination of renal tissue, dogs in the LP and MP groups had trace to mild mineralization of renal tissue, and dogs in the SC group had moderate mineralization and cellular necrosis of proximal renal tubules., Conclusions and Clinical Relevance: Pamidronate disodium is a potentially useful drug to reduce CCF-induced toxicosis and other causes of hypercalcemia associated with increased bone resorption in dogs.

A sample identified as "Warbex pour-on," expected to contain 13.2% famphur, and bovine tissue samples from 2 heifers that died after exhibiting signs of organophosphate intoxication were analyzed by gas chromatography/mass spectrometry (GC/MS). A product formulation problem was suspected because brain cholinesterase activities were depressed in both animals. Electron impact (EI) GC/MS of the pour-on revealed 9.7% famphur and an unidentified peak with approximately 76% of the peak area of the famphur. The unidentified peak showed a molecular ion at m/z 313, with a single Cl isotope cluster. Methane chemical ionization (MeCI) MS confirmed the molecular weight at 313 (1 Cl). A search on the molecular formula C9H17N3O3PSCl yielded a single match, isazophos. EI and MeCI GC/MS of reference isazophos confirmed the identity of the suspect peak. The concentration of isazophos in the pour-on was determined to be 6.0%. Famphur and isazophos were identified by their EI spectra and GC retention times in extracts of liver and brain from the 2 deceased animals. A GC/MS procedure utilizing selected ion monitoring (SIM) was developed for quantification of isazophos in liver, kidney, muscle, and fat of additional affected animals sacrificed at various times after exposure. Isazophos remained in animal tissues for as long as 94 days after topical exposure. Isazophos was present in fetal liver 70 days after exposure of the dam. High levels (6-3,500 ppm) of isazophos and famphur remained on the skin at 39 days postexposure.

Objectives: To determine whether pamidronate disodium can reduce vitamin D3-induced hypercalcemia in dogs and whether combination treatment with calcitonin is more effective than treatment with pamidronate alone., Animals: 20 clinically normal male Beagles., Procedure: All dogs were given 8 mg of cholecalciferol (CCF)/kg of body weight once orally, then were assigned randomly to 4 groups of 5 dogs each. Dogs were given 0.9% NaCl solution IV (group 1), calcitonin SC and 0.9% NaCl solution IV (group 2), pamidronate and 0.9% NaCl solution IV (group 3), or a combination of all 3 agents (group 4). Dogs were observed for 28 days, and serial blood and urine samples were collected for determination of serum biochemical, electrolyte, and 25(OH)D3 values, CBC, and urine mineral excretion. Samples of kidney, stomach, lung, aorta, liver, duodenum, and brain were evaluated by light microscopy and quantitative mineral analysis., Results: Two dogs in group 1 were euthanatized 4 days after CCF administration because of severe clinical signs of disease. Dogs in group 3 lost less weight and had significantly lower serum phosphorus, total and ionized calcium, and urinary zinc concentrations, compared with dogs in group 1. On day 4, serum urea nitrogen concentration was significantly lower in dogs of groups 3 and 4, compared with dogs in group 1. Mild to moderate mineralization of kidneys and stomach were observed in the 2 group-1 dogs euthanatized on day 4., Conclusions: Pamidronate administration effectively prevents CCF-induced hypercalcemia and mineralization of soft tissues., Clinical Relevance: Pamidronate is a potentially useful antidote against CCF toxicosis in dogs.

As part of annual colony counts in Santa Cruz Province, Argentina, a health survey of rockhopper penguins (Eudyptes chrysocomes) was conducted in 1994. Forty-five birds were examined during handling procedures, and blood and fecal samples were collected for laboratory analysis. All birds appeared to be in good condition. No ecto- or endoparasites were found. Hematology, plasma chemistry, and plasma mineral levels were measured and correlated with the results of bacterial and viral serology. Antibodies against Chlamydia sp., avian adenovirus, avian encephalomyelitis virus, infectious bronchitis virus, avian reovirus, and paramyxovirus-1, -2, and -3 were found. Mean plasma chemistry and mineral values differed between individuals testing positive and negative on serologic tests. There was no serologic evidence of exposure to avian influenza virus, duck viral enteritis, infectious bursal disease, infectious laryngotracheitis, Aspergillus sp., or Salmonella pullorum. Trace amounts of endrin were found in the plasma of one bird, but all other chlorinated pesticide and polychlorinated biphenyl levels were below detectable limits.

Twenty free-ranging guanaco (Lama guanicoe) in Chubut Province, Argentina, were immobilized for health evaluations. All but two animals appeared to be in good condition. Hematology, serum chemistry, and vitamin and mineral levels were measured, and feces were evaluated for parasites. Serology tests included bluetongue, brucellosis, bovine respiratory syncitial virus, bovine viral diarrhea/mucosal disease, equine herpesvirus 1, infectious bovine rhinotracheitis, Johne's disease (Mycobacterium paratuberculosis), foot and mouth disease, leptospirosis (17 serovars), parainfluenza-3, and vesicular stomatitis. Blood samples from 20 domestic sheep (Ovis aries) maintained in the same reserve with the guanaco were also collected at the same time for serology tests. No guanaco had positive serologic tests. Sheep were found to have antibody titers to bovine respiratory syncytial virus, Johne's disease, leptospirosis, and parainfluenza-3. There was no apparent difference in external appearance or condition, or statistical difference in blood test values, between the animals that were positive or negative for parasite ova.

Eight free-ranging black spider monkeys (Ateles paniscus chamek) were immobilized with Telazol in Bolivia for the purpose of radio-collaring. During this procedure, the animals received complete medical examinations, and samples were collected for health analyses. Biochemical test results varied with the degree of condition of the animals, and a variety of physical abnormalities were found. Evidence of previous infections with Leptospira sp., encephalitis virus, and yellow fever virus was found. All findings contribute to establishing baseline health values for the species. The handling of primates for research projects provides a valuable opportunity to collect health-related data and samples that can contribute to wildlife management and conservation efforts. The capture and handling of free-ranging primates is always accompanied by risk of injury or mortality. It is ethically important to maximize the amount of information gathered during these procedures. Furthermore, sharing the undesirable impacts with the scientific community enables informed decisions to be made during future project development.

As part of ongoing ecological studies of black-faced impala (Aepyceros melampus petersi) in northern Namibia, blood samples were collected and analyzed from 26 animals captured for translocation in 1992. All animals appeared to be in good condition and no abnormality was noted during physical examination. Serum chemistry and mineral levels were measured and correlated with the results of bacterial and viral serology and were within the normal ranges for domestic ruminants. Antibody titers for infectious bovine rhinotracheitis and bovine viral diarrhea were detected. Serological tests for bluetongue, foot-and-mouth disease, rinderpest, parainfluenza 3, brucellosis, leptospirosis, and anaplasmosis were negative. Significant differences in disease prevalence were not found between sexes.

As part of ongoing ecological studies and reproduction enhancement efforts for macaws in southwestern Peru, a health survey of parent- and hand-reared scarlet macaws (Ara macao) and blue and gold macaws (Ara ararauna) was conducted in 1994. Thirty-three birds were examined during handling procedures, and blood samples were collected from 27 (9 parent reared, 18 hand reared) for laboratory analysis. All but one bird appeared to be in good condition, with no abnormality noted during physical examination. Hematology, plasma chemistries, and plasma vitamin and mineral levels were studied and correlated with the results of bacterial and viral serology. Positive antibody titers for Salmonella and psittacine herpesvirus were found. These diseases have the potential to affect wildlife population dynamics, and Salmonella may have public health significance. Serological tests for avian influenza, infectious laryngotracheitis, paramyxovirus-1, -2, -3, polyoma virus, chlamydiosis, and aspergillosis were negative. Differences in disease prevalence were found between rearing situations.

Liver copper concentration is generally considered the best measure of copper nutritional status in cattle. Ultrasonic nebulization in conjunction with inductively coupled plasma-atomic emission spectroscopy (ICP-AES) was investigated as a method to provide adequate sensitivity to allow accurate simultaneous measurement of copper and 14 additional elements from needle biopsy samples. The element concentration frequency distribution profile of 12 elements routinely present in liver was compared to profiles of the elements in fat, muscle, vena cava, kidney, and clotted blood. The profiles could be used to confirm the authenticity of the liver biopsy sample. Element concentrations in biopsy samples taken in triplicate from the five lobes of a bovine liver were compared to those from triplicate wedge sections taken adjacent to the biopsies and analyzed by conventional ICP-AES. Precision between biopsies was equal to or better than precision between wedge samples. Some element concentrations determined by the biopsy procedure differed statistically from those determined by the wedge procedure, but differences were not sufficient to influence clinical interpretation of data.

We used inductively coupled plasma-atomic emission spectroscopy to measure serum iodine to determine plasma clearance of iohexol, an iodinated radiographic contrast agent. We determined I at 178.276 nm on the phosphorus 178.287 nm channel of the polychromator by utilization of spectrum shifter offset software, while correcting for P with the sequential P 214.914 nm emission line. Determination of I on the polychromator provided excellent precision in the measurement of serum I, even though the interelement correction of P was done with a sequential P line. Total imprecision (CV) (n = 13) was 16% (at 13.7 mg/L I), 8.6% (28.7 mg/L), 3.6% (59.0 mg/L), 2.6% (120.5 mg/L), 1.7% (237.8 mg/L), 1.2% (478.7 mg/L), and 1.8% (597 mg/L). The linear range was 15 to 600 mg/L. Iohexol added to serum (mg/L I) and recoveries (%) were 15 (91.3%), 30 (95.7%), 60 (98.3%), 120 (100.4%), 240 (99.1%), 480 (99.7%), and 600 (99.5%). Studies on dogs and cats administered a single intravenous injection of iohexol indicated that a dose of 300 mg I/kg body weight was sufficient for measurement of glomerular filtration rate by using a single compartment model for plasma clearance with three samples drawn 3 to 7 h after treatment. With this protocol, correlation coefficients were > 0.99 on the beta phase of the plasma disappearance curve.

Objective: To document and determine changes in the mineral profiles of sera and mammary secretions from a population of periparturient mares., Animals: 18 clinically normal periparturient Arabian broodmares., Procedure: Inductively coupled argon emission spectroscopy was used to measure Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn concentrations in sera and mammary secretions of periparturient mares. In addition, S was measured in mammary secretions., Results: Serum concentrations of Ca, Cu, Fe, K, Mg, Na, P, and Zn remained constant throughout late pregnancy and the first 7 days of lactation. Compared with values on day 11 before foaling, mammary fluid concentrations of Ca, Cu, K, Mg, P, S, and Zn increased prior to parturition and all element concentrations, except Ca, decreased with the onset of lactation. In contrast, Na concentrations in mammary secretions decreased precipitously as parturition approached. Iron concentrations in mammary secretions remained relatively constant up to the time of parturition, decreased at parturition, and remained constant during lactation., Conclusions and Clinical Relevance: Prior to foaling, increasing concentrations of Ca, Cu, K, Mg, P, S, or Zn in mammary secretions in concert with precipitous decreases in Na concentrations may provide a predictive index of impending parturition in the mare and a means of assessing fetal readiness for birth.

: Mink and otters are valuable wildlife resources and management efforts in North America and Europe have been directed towards re-establishing extirpated populations or expanding existing populations. The similarity of otter and mink habits and trophic status may allow inferences about the suitability of the habitat that is occupied by one species (mink) for the other species that is absent (otter). Remnant otter populations in Illinois have not expanded even though suitable habitat appears to be available and is occupied by mink. Low contaminant concentrations in tissues of mink trapped in a habitat where otters are not found and metal and organochlorine concentrations in tissues of otters incidentally collected by the Illinois Department of Natural Resources, suggest that environmental contaminants should not hinder natural expansion of otters in Illinois.

Three bald eagles (Haliaeetus leucocephalus), a red-tailed hawk (Buteo jamaicensis), and two coyotes (Canis latrans) found in a field in north-central Kansas (USA) in December 1992 were poisoned by flowable carbofuran (Furadan 4F) placed on sheep (Ovis aries) carcasses to kill coyotes. The carbofuran was placed on the carcasses in October 1992, but the coyotes and raptors apparently were killed in late December. Thus, flowable Furadan can cause direct and secondary deaths of wildlife under some circumstances for at least 60 days following placement.

Twelve Hereford steers (average BW = 231 kg) that had previously grazed native rangeland (Range) or irrigated winter wheat pasture (Wheat) were allowed to graze locoweed-infested rangeland from April 1 to June 9, 1994 (six steers/previous grazing treatment). Relative consumption level of locoweed and other forage classes was measured as observed bites per steer. Liver biopsy and whole blood samples were obtained from each steer before and after grazing. Liver samples were analyzed for several minerals by inductively coupled plasma-atomic emission spectroscopy, and whole blood samples were analyzed for Se. Liver concentrations of Ba (P < .001), Cd (P < .001), Ca (P < .01), Cr (P < .01), Ni (P < .001), Na (P < .01), and V (P < .001) were greater and concentrations of Mn (P < .09), P (P < .01), and K (P < .07) were less in Wheat than in Range steers. Liver concentrations of Fe, Mg, S, and Zn and whole blood Se concentrations did not differ (P > .10) between the two groups. Liver concentrations of Cr (P < .04) and Mn (P < .001) were less, and Fe concentrations were greater (P < .01), in samples taken after grazing than in samples taken before grazing of locoweed-infested range. Whole blood Se concentrations decreased (P < .01) from the beginning to the end of the grazing period, but this effect was not related (P > .15) to locoweed consumption. Changes in liver concentrations of minerals were compared relative to consumption levels of all forage classes in the locoweed-infested range. Liver concentrations of Cu decreased (r2 = .45; P < .02) as the percentage of bites consumed as locoweed increased, but concentrations after grazing locoweed-infested range were still within normal ranges. Changes in liver concentrations of other minerals were not related (P > .15) to consumption of locoweed. These data indicate that previous grazing history can have significant effects on liver mineral stores and that, under our conditions, consumption of locoweed by grazing beef steers altered liver Cu concentrations. Toxic effects of locoweed consumption would likely occur before Cu deficiency would be induced by grazing locoweed-infested range; hence, supplementation of Cu would seem unlikely to alter the course of locoweed toxicosis.

Neonatal llamas must receive supplemental milk when the dam has inadequate milk yield or fails to accept the cria. Data on llama milk composition are limited, and selection of suitable milk supplements has been difficult. Milk from 83 llamas on eight farms in four states (Illinois, Kentucky, Michigan, and Colorado) was collected, and milk composition was analyzed. Llamas had no history or signs of mastitis, and major mastitis pathogens were not isolated from the milk. Total solids were determined gravimetrically. A colorimetric method, a dye-binding assay, and the modified Mojonnier method were used to quantify lactose, protein, and fat, respectively. Concentrations of seven macrominerals and 17 trace elements were obtained by inductively coupled plasma atomic emission spectroscopy, and Cl was quantified by anion chromatography. Llama milk was higher in sugar (6.5%) and lower in fat (2.7%) and energy content (70.0 kcal/100 g) than milks of domestic ruminants. Llama milk also contained more Ca and less Na, K, and Cl. In general, milk composition was not affected by stage of lactation, lactation number, or body condition score of the llama, but several milk constituents varied among farms.

Objective: To determine whether prolonged feeding of preterm infant formula to preterm infants can accelerate recovery to normal plasma zinc levels without affecting plasma mineral homeostasis., Design: Part of concurrent prospective feeding trials in a university hospital-based population., Subjects and Intervention: Preterm infants (n = 33; birth weight, 1037 +/- 157 gm) were fed a preterm infant formula with higher concentrations of zinc, copper, calcium, magnesium, and potassium until 2 months past expected term, then a term infant formula. Term infants (n = 38; birth weight, 3318 +/- 401 gm) fed this term infant formula from birth were a reference group for comparison with study infants and with published values. Plasma mineral levels were analyzed by inductively coupled plasma atomic emission spectroscopy., Results: Preterm infants fed a preterm infant formula after discharge from the hospital appeared to achieve normal plasma zinc concentrations by at least 2 months past term without adverse effects on mineral homeostasis.

Thirty-six male mink were fed diets that contained 0, 1, 2 or 4% supplemental salt (sodium chloride) and were given drinking water ad libitum for 7 d. Three mink on each diet were then placed on ad libitum, 50% ad libitum or 25% ad libitum drinking water for the next 14 d. Ad libitum water consumption was directly proportional to the salt content of the diets. Feed consumption was inversely related to the level of dietary salt, although water restriction had a greater effect in reducing feed consumption than did the supplemental salt. The clinical signs of salt toxicity-water restriction observed were increased thirst, mild dehydration, decreased feed consumption, decreased body weight, rough coat, crusty nose and eyes, irritability in the early stage, and lethargy in the later stages. In general, serum and urinary sodium and chloride ion concentrations increased with increasing dietary salt concentrations. Expressed as a percent of brain weight, liver, spleen, kidney and heart weights of mink fed supplemental salt were less than the control weights. Adrenal gland weights increased in response to water restriction. Brain sodium concentrations were not affected by salt supplementation when drinking water was provided ad libitum. However, restricting drinking water generally resulted in increased brain sodium concentrations. Mild to moderate micro- or macrovesicular vacuolar changes were observed in the livers of some mink fed each level of dietary salt, but were especially prominent in the mink restricted in drinking water.

Adult female mink previously fed diets containing 0 (control) and 6.25 mg heptachlor/kg diet for 181 days were fed either the same control diet ad libitum (AL) or the control diet containing 10% mineral oil and restricted by 45% of ad libitum intake (MO/R) for 21 days to determine the efficacy of the latter treatment in enhancing the elimination of heptachlor epoxide (HE) from mink. Kit mink (2-3 months of age) whelped by dams of the control and 6.25 mg/kg groups were also fed the MO/R or AL diets for 21 days. Daily consumption (g/kg bw/day) of the AL diet by kit mink was significantly greater than consumption of the same diet by the adult females. Body weights of the control adults and the control and 6.25 mg/kg kits were significantly reduced by feeding the MO/R diet. Two adults from the control group and one adult from the 6.25 mg/kg group fed the MO/R diet died during the 21-day period. No mortalities occurred in kit mink fed either diet. Administration of the MO/R diet caused a significant reduction in body fat of the control adults and kits, but not in the 6.25 mg/kg adults and kits. Decreases in body fat of the MO/R groups were not associated with greater elimination of HE when compared to the AL groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Fifty-five hematologic, blood gas, blood chemistry, and serum mineral values were determined from a random sample of 29 clinically healthy goats from an equal number of randomly selected herds in the piedmont of North Carolina. Descriptive statistics and equations for calculated values are presented. The internal and external validity of the data is discussed.

Adult female mink were fed diets containing 0 (control), 6.25, 12.5, and 25 ppm (micrograms/g) technical grade heptachlor prior to and throughout the reproductive period (181 days) to evaluate the effects of heptachlor consumption on reproduction and offspring viability and to assess the extent of placental and mammary transfer of heptachlor epoxide to mink offspring. Feeding 12.5 and 25 ppm resulted in significant reductions in feed consumption and body weights of female mink. Mortality was 0, 8, 67, and 100% for the control, 6.25, 12.5, and 25 ppm groups, respectively. All females in the 25 ppm group died within 88 days. Mink fed the two higher heptachlor diets displayed clinical signs indicative of central nervous system involvement just prior to death. Females were mated with males on the same dietary treatments. Whelping success rates were 67, 83, 27, and 0% for the control, 6.25, 12.5, and 25 ppm groups, respectively. High mortality in the 12.5 and 25 ppm groups accounted for the lack of reproductive success. Gestation length, litter size and birth weight of kits were not significantly affected by adult female consumption of 6.25 ppm heptachlor while kits helped by females on the 12.5 ppm diet weighed significantly less than control kits at birth. Survival of kits in the 12.5 ppm group from birth to three weeks of age was also adversely affected. At three and six weeks of age, kit body weights in both the 6.25 and 12.5 ppm groups were significantly less than body weights in control kits.(ABSTRACT TRUNCATED AT 250 WORDS)

Mass spectrometry/mass spectrometry (MS/MS) with collision-activated dissociation (CAD) was utilized to unequivocally distinguish 1,3-indandione rodenticides in 2 cases of anticoagulant toxicosis. Anecdotal evidence provided by the veterinarian in a case involving feedlot cows and physical evidence at the site of occurrence in a similar case involving lambs strongly implicated diphenadione (diphacinone; DP) in both instances. However, high performance liquid chromatography indicated chlorophacinone (CP), not DP, was present in the blood samples obtained from both cows and lambs. Intact 1,3-indandiones exhibit poor gas chromatographic properties, so procedures were developed for analysis by MS/MS using a direct exposure probe for sample introduction. The EI mass spectra of DP and CP contained a base peak at m/z 173, with molecular ions (M+) at m/z 340 and m/z 374 (Cl isotope cluster), respectively. Corresponding MS/MS CAD parent ion spectra of m/z 173 showed an ion of m/z 340 for DP and 374 (Cl cluster) for CP. CAD analysis of the blood extracts showed a parent ion scan of m/z 173 identical to that of CP, with the m/z 374 (Cl cluster). (Additional evidence was obtained by MS/MS examination of the CAD daughter ion spectrum of m/z 374.) Blood extracts from the affected animals revealed CAD daughter ion spectra for m/z 374 identical to that of reference CP. Positive confirmation of CP in both cases led to identification of the source of the toxicant and prevention of further animal exposures.