Skeletal muscles from healthy dogs and Labrador Retrievers with hereditary muscular dystrophy were examined morphologically and histochemically and were analyzed biochemically for Na+, K+, Ca2+, Mg2+, Zn2+, Cu2+, Cl-, total muscle water, and total neutral lipid content. Flame atomic absorption spectrophotometer was used for elemental quantitation of hydrochloric acid tissue extracts. Muscle samples from dystrophic dogs contained substantially increased concentrations of Na+, Ca2+, Zn2+, Cu2+, and Cl-, and a considerable reduction in the content of K+ and Mg2+ compared with samples from healthy dogs. Total muscle water and total fat content was higher in muscles from dystrophic dogs. Most muscle samples from dystrophic dogs had a type-2 fiber deficiency and an increase in number of fibers with internalized nuclei.

Intestinal lesions of transmissible gastroenteritis (TGE) virus infection in conventionally reared pigs suckling either nonvaccinated, vaccinated, or previously infected sows were studied by scanning electron microscopy, light microscopy, and immunofluorescent microscopy for TGE viral antigen. Pigs were inoculated with virulent TGE virus when they were 5 or 21 days old and were euthanatized shortly after the onset of diarrhea or 96 hours after inoculation if no diarrhea developed. Pigs inoculated when they were either 5 or 21 days old and suckling nonvaccinated sows developed severe lesions, including swelling and necrosis of enterocytes and severe villus atrophy. Pigs inoculated when they were 5 days old and suckling sows vaccinated with attenuated vaccines developed less-severe villus atrophy, and those suckling sows immunized by exposure to nonattenuated TGE virus developed moderate or no villus atrophy. Pigs inoculated when they were 21 days old and suckling sows vaccinated with attenuated vaccines had severe villus atrophy, whereas those suckling sows immunized by exposure to nonattenuated virus had more-moderate villus lesions. Villus atrophy was inhibited to various degrees in pigs suckling immunized sows, depending in part on the antibody titer in the colostrum and milk.

Twenty-one pregnant mares with single or twin conceptuses between 41 and 65 days of gestational age were allotted to 5 treatment groups. A ventral median celiotomy was performed in all mares. In group-1 mares (3 mares, single conceptus), the uterus and fetus were palpated for 5 minutes. In group-2 mares (3 mares, single conceptus, flunixin meglumine), 250 ml of sterile placental fluid was injected into the nongravid uterine horn. In group-3 mares (4 mares, unicornuate twin conceptuses), group-4 mares (3 mares, unicornuate twin conceptuses, flunixin meglumine), and group-5 mares (8 mares, bicornuate twin conceptuses, flunixin meglumine), 1 conceptus was removed from the uterus via hysterotomy. All mares received progesterone prophylactically until day 100 of gestation or until the fetus died. The 3 mares in group 1 delivered clinically normal, live foals. The mean prostaglandin F2 alpha metabolite (PGFM) plasma concentration peaked at 180 +/- 5.2 pg/ml during uterine manipulation and fetal palpation, then declined to baseline by 1 hour. Free placental fluid (group 2) undermined the chorioallantois ventrally and resulted in fetal death within 3 hours after surgery. The mean PGFM plasma concentration peaked at 39 +/- 4 pg/ml following injection of placental fluid. None of the remaining fetuses in the 7 mares with unicornuate twin conceptuses (groups 3 and 4) survived. Five mares with unicornuate twin conceptuses (group 5) delivered single viable foals. In another mare in group 5, the fetus was alive 4 days after surgery, when the mare was euthanatized for a fractured femur. The peak mean PGFM plasma concentration during hysterotomy in the mares not treated with flunixin meglumine (group 3) was 1,979 +/- 27.36 pg/ml, and the highest peak mean PGFM plasma concentration in the flunixin meglumine-treated hysterotomized mares (groups 4 and 5) was 123 +/- 4.8 pg/ml. Flunixin meglumine was at least 94% effective in inhibiting expected increases in PGFM plasma concentrations associated with hysterotomy.

Transrectal ultrasonography was performed on the cranial mesenteric artery and its major branches in 23 conscious adult horses. Ultrasonographically, 25 arterial segments were classified as either normal or abnormal. These ultrasonographic classifications were later compared with the gross and histologic evaluations of each artery following necropsy of each horse. In this study, transrectal ultrasonography as a diagnostic test for verminous arteritis had a 90% sensitivity for detecting normal arteries and an 86% specificity for detecting abnormal arteries, suggesting that ultrasonography may be useful in the antemortem diagnosis of verminous arteritis.

Antibodies to bovine serum albumin were detected in swine sera by use of an immunoblotting technique. Such sera had false-positive reactions, as determined by results of African swine fever virus serodiagnostic techniques when bovine serum albumin was a contaminant in the soluble cytoplasmic antigen obtained from infected cells cultured in the presence of bovine serum. The soluble cytoplasmic antigen obtained from cell cultures infected with African swine fever virus in the presence of porcine serum did not react with the false-positive sera and, therefore, was used for African swine fever virus serodiagnostic methods, with 0% false-positive results.

Thirty-two isolates of Campylobacter fetus subsp venerealis were obtained from 1 bull and 4 heifers with experimentally induced infection. When whole-cell antigens of isolates were cross titrated with antisera to the infecting strain, isolates from 3 heifers had limited antigenic variation, whereas whole-cell antigens of isolates from 2 cattle (the bull and a heifer) differed serologically from those of the infecting strain. Changes were detected specifically in 6 heat-labile antigens. Of the 6 heat-labile factors evaluated, all were initially present on the infecting parent strain, but not on early isolates obtained from 4 of the 5 cattle. Restriction enzyme analysis revealed minor variation in the DNA fingerprints of isolates obtained from individual cattle, thus implying stability of the Campylobacter genome once persistent infection is established. Isolates with identical restriction enzyme patterns expressed different heat-labile antigens. Correlation could not be found between the DNA electrophoretic pattern and the expression of heat-labile antigens.

Serum trypsinogen concentration was studied in 6 adult mixed-breed dogs randomly fed diets containing 6.8, 31.4, or 39.7% protein (dry weight) for 3 weeks each. Blood was collected on days 20, 21, and 22 of each feeding period, and serum trypsinogen concentrations were determined by radioimmunoassay of trypsin-like immunoreactivity (TLI). Mean serum TLI concentrations for each dog fed each diet were compared. A significant (P < 0.05) positive linear relationship (P < 0.02) was determined between serum TLI concentrations and the percentage of dietary protein. Mean serum TLI concentrations for each dog fed all diets ranged from 5.7 to 20.2 microgram/L.

In addition to its well-known physicochemical properties, hyaluronate (HA) has recently been shown to have important biological and pathophysiologic regulatory effects on granulocytes, monocytes, fibroblasts, and endothelial cells, as well as on the healing of wounds and various joint disorders. Many of these effects depend on or are reflected in the concentration and degree of polymerization of HA. Therefore, high-performance liquid chromatography with size-exclusion column was used to characterize the concentration and degree of polymerization of HA in equine synovial fluid (SF). The mean (+/-SD) HA concentration was 0.47 +/- 0.19 mg/ml and there was no difference between control joints and those with positive response to local anesthetic administration (0.61 +/- 0.20 mg/ml vs 0.42 +/-0.17 mg/ml), suggesting that in horses with acute traumatic synovitis causing lameness, HA concentration in SF cannot be used as a marker for the condition. High-performance liquid chromatograms disclosed considerable variation between horses in the degree of polymerization reflected in the peak area to height ratio (mean +/-SD, 3.207 +/- 0.447; range, 2.229 to 3.915), indicating differences in local synthesis, degradation, or mobilization into lymph of SF HA. In addition, the correlation between SF HA concentration and degree of polymerization was 0.760 (P < 0.01; linear regression analysis) suggesting that HA concentration and chain length are independently regulated.

Fetal and neonatal lamb hemostasis were studied from the 60th day of pregnancy to birth. Platelet counts and blood coagulation, as assessed by tests such as recalcification time and thromboelastography, were similar in fetuses, neonates, and adult sheep. The values of coagulation factors were low, ie, vitamin K-dependent Factors II, VII, IX, and X remained unchanged (30 and 40% of adult reference values) until the last 10 days of gestation, and then increased until birth (40 to 60%). Values of fibrinogen and Factor V followed a similar pattern, although their activities became identical to adult values at birth. Also, we measured values of protein C and antithrombin III, which are synthesized by the liver. The importance of hepatic failure and fetal vitamin K deficiency were discussed. Factors VIII and XII activities increased gradually during pregnancy to reach adult values at birth. Fetal fibrinolytic activity increased. This could not be explained by the values or tissue-type plasminogen activator (it was not detectable) or by the presence of its fast-acting inhibitor, whose concentration did not decrease.

The effects of sodium bicarbonate (0.5 mEq/kg of body weight, 1.0 mEq/kg, 2.0 mEq/kg, and 4.0 mEq/kg) on ionized and total calcium concentrations were determined in clinically normal cats. Also, serum pH, whole blood pH, and serum albumin, serum total protein, and serum phosphorus concentrations were measured. Intravenous administration of sodium bicarbonate to awake cats decreased serum ionized calcium and serum total calcium concentrations. All dosages of sodium bicarbonate were associated with significant decreases of serum ionized calcium concentration. This effect lasted for greater than 180 minutes when cats were given 2.0 mEq/kg or 4.0 mEq/kg. When cats were given 4 mEq of sodium bicarbonate/kg, serum ionized calcium concentration was significantly decreased, compared with that when cats were given lower doses, but only at 10 minutes after infusion. After sodium bicarbonate infusion, serum total calcium concentration, measured by ion-specific electrode and colorimetry, was lower than baseline values at most of the times evaluated. Decreases in serum ionized calcium and serum total calcium concentrations can be attributed only in part to an increase in serum or whole blood pH and to a decrease in serum protein concentration. Serum total calcium concentrations measured by ion-specific electrode and by colorimetry were positively correlated, but the variability was high. Only 44% of the varibility in serum ionized calcium concentration could be predicted when serum total calcium, albumin, total protein, phosphorus, and bicarbonate concentrations and pH were considered.