Trace element concentrations in perinatal beef calves from west central Nebraska.

Trace element analyses were performed on 144 livers from perinatal calves submitted to the Veterinary Science Laboratory, North Platte, NE. All calves originated from herds in west-central Nebraska and ranged in age from 8 months of gestation up to 6-week-old neonates. Calves were divided into 5 categories based on objectives gross examination and ocular fluid evaluation: abomasal ulcers, abomasal tympany, diarrhea, stillborn and excessive nitrate exposure. Excessive zinc concentrations were found in 4 of the 5 categories. Only in the abomasal ulcer category could a correlation be found; this category routinely was found to have deficient to low normal liver copper concentrations and highest liver molybdenum concentrations. Both excesses and deficiencies of selenium and iron occurred in all categories.

Element concentrations in livers and kidneys of ranch mink.

Reference ranges for element concentrations in livers and kidneys of "healthy" mink of known age, sex, and coat color and fed a conventional diet were determined. After euthanasia and removal of the pelts, liver and kidney samples were collected from 174 mink and analyzed for 22 elements using inductively coupled argon plasma emission spectroscopy. The diet of the mink was also analyzed for element concentrations. Descriptive statistics of element concentrations for livers and kidneys of the mink are given and compared with dietary element concentrations.

Monensin poisoning in horses - an international incident.

Several hundred Michigan horses were accidentally exposed to varying levels of monensin. Severity of effects was proportional to the level of feed contamination; sudden death resulted on at least two premises. Acute signs of cardiovascular impairment occurred on one premises having received feed containing over 200 grams of monensin per tonne. Gross and histological postmortem lesions consisted of acute myocardial necrosis. Although only circumstantially confirmed, investigations led to the suspicion that the source of poisoning was a ration formulation error in a feedmill in southwestern Ontario. Concern over possible undetected heart damage in exposed horses led to clinical monitoring on one farm over a period of several months. Electrocardiographic and serum enzyme monitoring were used soon after the incident to implicate exposure in some horses; they were poor prognostic indicators. Applicable legislation, the cooperative role of government departments, and legal implications relative to potential prosecution and lawsuits arising from sale of contaminated feed between Canada and the USA are summarized.

Determination of embutramide in mammalian tissues.

T-61 is a commonly used euthanasic agent containing N-[2-[m-methoxyphenyl)-2-ethyl-buty1(1)]-gamma-hydroxybutyramid e (embutramide), 4,4'methylenebis(cyclohexyl-trimethylammonium iodide), and tetracaine hydrochloride. In order to confirm the exposure of animals and man to T-61, a procedure was developed for identification and quantification of embutramide in tissues and body fluids. Tissue was homogenized in acetonitrile (CH3CN) and the drug partitioned into methylene chloride (CH2Cl2) from aqueous CH3CN at neutral pH and at pH 9. The drug was purified by gel permeation chromatography in cyclohexane/CH2Cl2 (85:15). Embutramide was identified by gas chromatography-mass spectrometry on a 0.25 mm x 15 m fused silica capillary column of 0.25 micron DB-5, programmed from 215 to 275 degrees C at 25 degrees/min with El ionization at 70 ev. Quantification was selected ion monitoring of m/z 135, 190 and 293. Embutramide was examined in brain, lung, liver, kidney, skeletal muscle, urine, bile, eye fluid and blood of bovine, canine, caprine, feline, ovine and porcine species.

Multielement assay of perinatal lamb livers by inductively coupled argon plasma emission spectroscopy.

During the 1986 lambing season, 33 Michigan sheep producers submitted all lambs that had died before weaning to the Michigan State University Diagnostic Laboratory for necropsy. Inductively coupled argon plasma emission spectroscopy was used to measure 22 elements in the liver of 888 of the lambs submitted. Mean concentrations of each element were established and compared with literature values of established deficient, normal, and toxic concentrations. Mean values in milligrams per kilogram of wet weight were as follows: Al, 3.843; As, less than 1; Ba, 0.176; Ca, 128.2; Cr, 0.778; Cu, 56.82; Fe, 491.6; Hg, less than 2; K, 2,150; Mg, 138.4; Mn, 2.776; Mo, 0.489; Na, 1,384; P, 2,583; Pb, 1,453; Sb, less than 1; Tl, less than 5; Zn, 68.31. In only 11 lambs did the liver contain As, B, Cd, Co, Hg, Sb, Se, or Tl in detectable concentrations.

The induction of equine laminitis with an aqueous extract of the heartwood of black walnut (Juglans nigra).

An aqueous extract of the heartwood of black walnut (Juglans nigra) was given via stomach tube to 10 horses. Eight developed Obel grade 3 or 4 laminitis within 12 hr. Limb edema and mild sedation were the only other clinical signs observed. One horse was euthanized due to severe signs. The other 7 recovered within 6 days. Gas chromatography/mass spectrometry of aqueous extracts of heartwood, bark and nuts of black walnut identified juglone in the bark and nuts, but not in the heartwood. It was concluded that the aqueous extract of heartwood is laminogenic to horses, but the active ingredient is not juglone.

An epidemiologic study of mortality in veal calves subsequent to an episode of zinc toxicosis on a California veal calf operation using zinc sulfate-supplemented milk replacer.

Ninety-five 3- to 6-month old male Holstein veal calves were evaluated after an episode of zinc toxicosis, to describe clinical signs and to identify management and/or host-related factors that may have contributed to death. Clinical signs appeared 23 days after feeding of milk replacer commenced. Of 85 calves examined, 64 had pneumonia (75.5%), 62 had ocular signs (72.9%), 46 had diarrhea (54.1%), 34 were anorectic (40.0%), 15 were bloated (17.6%), 8 had cardiac arrhythmias (9.4%), 3 had convulsions (3.5%), and 3 were polydipsic/polyphagic (3.5%). Clinical signs began to appear when calves each were being fed approximately 1.5 to 2.0 g of zinc/day and exposed to a cumulative zinc intake of 42 to 70 g, from a milk replacer containing 706 micrograms of elemental zinc/g of milk replacer. Of 95 calves studied, 1 died before zinc was supplemented, 16 died during the episode, 12 were euthanatized, 1 was lost to follow-up evaluation, 1 was culled, and 64 were slaughtered. Deaths attributable to zinc toxicosis were observed between 25 and 53 days after the milk replacer was supplemented with zinc. Calves died while being exposed cumulatively to 30 to 66 g of zinc. The factors of previous pneumonia severity, age, cumulative daily exposure to zinc, and calf location within a bay were examined for possible associations with mortality, using stepwise logistic regression. Though younger calves tended to have a higher mortality than older calves, neither age category nor severity of pneumonia, before zinc supplementation, accounted for a significant mortality.(ABSTRACT TRUNCATED AT 250 WORDS)

Multielement assays of canine serum, liver, and kidney by inductively coupled argon plasma emission spectroscopy.

Inductively coupled argon plasma emission spectroscopy was used to measure Al, As, Ca, Cd, Cr, Cu, Fe, Pb, Mg, Mn, Hg, Mo, P, K, Se, Na, Tl, and Zn in canine specimens (70 serum, 270 liver, and 200 kidney). Mean concentrations of each of these elements in detectable amounts in these samples were established, and histograms of the concentration distributions of elements in the samples were developed.

Multielement assays of bovine tissue specimens by inductively coupled argon plasma emission spectroscopy.

Inductively coupled argon plasma spectroscopy was used to generate multielement profiles of bovine serum (n = 607), liver (n = 229), and kidney (n = 90) samples submitted to the Animal Health Diagnostic Laboratory at Michigan State University, East Lansing. The presented frequency distribution histograms of element concentrations in the different samples provided a data base for diagnostic interpretations and illustrated some of the advantages, as well as limitations, of inductively coupled argon plasma for this purpose.

Altered serum element concentrations due to laboratory usage of Vacutainer tubes.

Aliquots of a pooled serum sample (bovine) were agitated in Vacutainer tubes (serum or clot tubes) for 0, 2, 8 and 32 hr to determine if Vacutainer tubes had any effect on serum trace element concentrations. The sera were analyzed for Ca, Cu, Fe, Mg, Na and Zn by the inductively coupled argon plasma emission spectrometer. The Zn concentration in sera was significantly increased over time, and the Cu and Fe concentrations were significantly decreased. Most of these artifacts became apparent within the first 2 hrs of exposure to the Vacutainer tubes. Changes in Cu, Mg and Na concentrations were not detected.