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Abstract

Objective

To determine activities of intracellular enzymes in 8 major organs in juvenile green iguanas and to compare tissue and plasma activities.

Animals

6 green iguanas < 1 year old.

Procedure

Lysates of liver, kidney, epaxial muscle, heart, lung, spleen, small intestine, and pancreas were analyzed for alkaline phosphatase (ALP), lactate dehydrogenase (LDH), aspartate transaminase (AST), alanine transaminase (ALT), γ-glutamyltransferase (GGT), creatine kinase (CK), glutamate dehydrogenase (GMD), and amylase (AMS) activities.

Results

In general, low tissue enzyme activity coincided with low plasma activity. The CK activity was high in epaxial muscle and the heart and low in all other tissues tested. The AMS activity was found exclusively in the pancreas. Moderate LDH and AST activities were found in all tissues. Low ALT and ALP activities were found in a variety of tissues. Plasma and tissue activities of GGT and GMD were low or undetectable.

Conclusions and Clinical Relevance

Results suggest that plasma CK activity may be muscle specific in iguanas, but high values may not always indicate overt muscle disease. The AMS activity may be specific for the pancreas, but the wide range of plasma activity would likely limit its diagnostic usefulness. Activities of AST and LDH may reflect tissue damage or inflammation, but probably do not reflect damage to specific tissues or organs. (Am J Vet Res 1999;60:201–203)

Free access
in American Journal of Veterinary Research

SUMMARY

Four 1-year-old steers were each inoculated orally with 10,000 Toxoplasma gondii oocysts of the GT-1 strain and euthanatized on postinoculation days (pid) 350, 539, 1191, and 1201. Samples (500 g) of tongue, heart, semimembranosus and semitendinosus muscles (roast), intercostal muscles (ribs), longismus muscles (tenderloin), brain, kidneys, liver, and small intestine were bioassayed for T gondii by feeding to cats and examination of cat feces for shedding of oocysts. Toxoplasma gondii was recovered by bioassays in cats from the 3 steers necropsied pid 350, 539, and 1191, but not from the steer euthanatized on pid 1201. Cats shed oocysts after ingesting tongue from 2 steers, heart from 3 steers, liver from 2 steers, and roast, ribs, brain, and intestines from 1 steer each. Toxoplasma gondii was not isolated from any of the other bovine tissues. In addition to tissues bioassayed in cats, homogenates of mesenteric lymph nodes, lungs, spinal cord, spleen, and eyes were bioassayed in mice for T gondii infection. Toxoplasma gondii was not recovered from the 135 mice inoculated with tissue from each of the 4 steers. All 4 inoculated steers developed high T gondii antibody titers (≥ 1:8,000) in the agglutination test, using formalin-fixed whole tachyzoites. In the steer euthanatized on pid 1201, agglutinating T gondii antibody titers decreased from 1:4,000 to 1:320 between 2 and 5 months after inoculation and to 1:20 by 19 months after inoculation.

Free access
in American Journal of Veterinary Research

Abstract

Objective

To elucidate the spatial and temporal expression of a porcine lactoferrin (LTF) gene.

Animals

4 female and 4 male Large White pigs.

Procedures

We examined LTF expression in various organs excised from the pigs, using northern blot hybridization with a porcine LTF cDNA probe. Antibodies against porcine LTF were raised in rabbits and were used along with immunohistochemical staining to localize the LTF protein.

Results

High amounts of porcine LTF mRNA were detected in the secreting mammary gland and epididymis. This distribution is consistent with that of porcine LTF examined by immunohistochemistry. In female pigs, porcine LTF mRNA concentration increased remarkably in the ductal cells of the lactating mammary gland then significantly decreased at day 21 after parturition. Furthermore, specific staining for LTF was observed in the epithelial cells of the gastrointestinal tract of female pigs, but not in the uterus, ovaries, spleen, kidneys, pancreas, muscles, heart, brain, lungs, or liver of postpartum female pigs, or in the testes of male pigs.

Conclusions

Gene expression of porcine LTF is closely related to lactation in the mammary gland. Distribution of LTF in the epididymis suggests that LTF may have a regulatory role in development of the reproductive tract of male pigs. (Am J Vet Res 1997;58:1152–1158)

Free access
in American Journal of Veterinary Research

Abstract

Objective

To identify eosinophil progenitor cells in feline bone marrow, establishing an assay method to use in studies of eosinophilopoiesis and eosinophilopoietic factors in cats.

Animals

Healthy, laboratory animal source cats.

Procedure

Sources of colony-stimulating activity were prepared by conditioning media with bone marrow, spleen, and blood mononuclear cells from cats infected with Toxocara canis. Bone marrow cells were aspirated and cultured to develop the eosinophil progenitor cell assay and to test cells from 9 healthy cats in the assay.

Results

Optimal conditions for identifying colonyforming units-eosinophil and cluster-forming units-eosinophil were as follows. Bone marrow mononuclear cells (105) were plated in 1 ml of supplemented medium, fetal bovine serum, and agar. The source of eosinophil growth factor(s) was bone marrow-conditioned medium made in the presence of 2.5 µg of concanavalin A/ml; other conditioned media also supported eosinophil colony growth. Dishes were incubated for 7 days at 37 C and 7% CO2. The colonyforming units-eosinophil formed aggregates of > 50 Luxol fast blue-positive cells and had dispersed morphology; the cluster-forming units-eosinophil formed aggregates of < 50 cells.

Conclusion and Clinical Relevance

Similar to other species, cats have separate and distinct eosinophil progenitor cells. The eosinophil progenitor assay may be used to characterize altered kinetics of eosinophilopoiesis, to assess eosinophil growth factors, and to evaluate therapeutic regimens that might be useful in the management of excess eosinophil production. (Am J Vet Res 1997; 58:348-353)

Free access
in American Journal of Veterinary Research

Summary

Concentration of sulfamethazine was measured in plasma and tissues (fat, liver, kidney, spleen, lungs, and skeletal muscle) of pigs given the drug iv and po. The plasma concentration vs time curve was best described by a 2-compartment model, with a distribution half-life of 0.46 hour and an elimination halflife of 16.9 hours. Bioavailability after oral administration was 85.8 ± 5.3%.

The tissue and plasma sulfamethazine concentration vs time data were used to develop a multicompartment pharmacokinetic model of sulfamethazine disposition in pigs. Plasma and tissue concentrations of sulfamethazine in pigs were measured at various intervals after multiple oral doses of sulfamethazine, and were compared to concentrations predicted by the model. Model predictions for tissue concentrations of sulfamethazine after addition of the drug to feed (110 μg/g of feed for 98 days; 550 μg/g for 30 days) were compared to results from other studies. The model accurately predicted the number of days for sulfamethazine concentration to fall below 0.1 μg of tissue/g (0.1 ppm, the tolerated concentration) in various tissues.

Free access
in American Journal of Veterinary Research

Objective

To describe 3 laparoscopic approaches for, and the normal laparoscopic anatomy of, the abdomen in adult llamas and to evaluate the effects of laparoscopy in those llamas.

Design

Prospective clinical trial.

Animals

Six adult castrated male llamas.

Procedure

After induction of general anesthesia, 3 surgical approaches to the abdomen were performed: left paralumbar, ventral midline, and right paralumbar. The abdomen was systematically examined, and anatomic features described. After recovery from anesthesia, all llamas were examined daily for 10 days and CBC was repeated 24, 72, and 120 hours after laparoscopy.

Results

Laparoscopy was successfully performed in all llamas by use of the ventral midline and right paralumbar approaches. The laparoscope was inadvertently placed into the left retroperitoneal space in 1 of the 6 llamas when the left paralumbar approach was used. Also, hemorrhage into the abdomen limited the view from the left side in another llama. Various approaches allowed viewing of the first and third forestomach compartments, liver, spleen, kidneys, small intestine, ileum, proximal loop of the ascending colon, spiral colon, and urinary bladder. Postoperative findings included subcutaneous emphysema and edema. Mean WBC count peaked 24 hours after surgery (mean, 23,500 cells/μl). Generally, neutrophil count increased and lymphocyte count decreased during the 120 hours after surgery.

Clinical Implications

Laparoscopy may be used for differentiation of medical and surgical lesions in the abdomen of llamas. The site for laparoscopy should be chosen on the basis of the most likely site of the suspected lesion.

Free access
in Journal of the American Veterinary Medical Association

Abstract

Laparoscopy was performed on 6 horses (2 mares, 2 geldings, 2 stallions) to determine the normal laparoscopic anatomy of the equine abdomen. After withholding feed for 36 hours, horses were examined from the left and right paralumbar fossae, and the visceral anatomic structures were recorded by videotape and photography. One mare developed emphysema located subcutaneously at the primary laparoscopic portal; otherwise, there were no complications. The anatomic structures of diagnostic importance that were observed in the left half of the abdomen were the hepatic duct; left lateral and quadrate lobes of the liver; stomach; spleen; left kidney with the associated nephrosplenic ligament; segments of jejunum, descending colon, and ascending colon; left side of the male and female reproductive tracts; urinary bladder; vaginal ring; and mesorchium. Important structures observed in the right side of the abdomen were portions of the common hepatic duct; left lateral, quadrate, and right lobes of the liver; caudate process of the liver; stomach; duodenum; right dorsal colon, epiploic foramen; omental bursa; right kidney; base of the cecum; segments of jejunum, descending colon, and ascending colon; urinary bladder; right half of the male and female reproductive tracts; and rectum.

Free access
in American Journal of Veterinary Research

Abstract

Objective

To assess whether foot-and-mouth disease virus (FMDV)-specific sequences could be identified in tissues from persistently virus-infected animals.

Design

Cattle with experimentally induced persistent FMDV infections were slaughtered at 750 days after viral exposure. Experimentally infected pigs were slaughtered at 28 days after FMDV inoculation. Postmortem specimens were asceptically removed.

Animals

Three bovids and 3 pigs were studied, as well as 1 control animal for each species.

Procedure

Various tissues were examined for the presence of FMDV-specific sequences by dot-blot hybridization assay, using a molecularly cloned FMDV cDNA corresponding to the polymerase coding region.

Results

The FMDV-specific genomic sequences were only detected in RNA from spleen, lung, larynx, tonsils, pancreas, liver, esophagus, and WBC of bovids.

Conclusions

It was established that, at late stages of the persistent infection, when virus isolation was not possible, cattle may carry FMDV-specific sequences in different tissues. Retention of viral sequences could not be demonstrated in specimens from experimentally infected swine, 28 days after viral inoculation.

Free access
in American Journal of Veterinary Research

Objective—

To evaluate the potential food safety risks constituted by recumbent cattle that are slaughtered for edible beef.

Design—

Prospective case series.

Animals—

Thirty cattle in recumbency that passed a routine antemortem inspection at a US federally inspected abattoir.

Procedure—

Aerobic, bacteriologic culture of blood samples taken immediately prior to slaughter and of spleens taken during viscera inspection. Gross lesions were recorded, and samples of liver, lung, kidney, and heart were collected from each animal for routine light microscopic examination.

Results—

Bacteremia caused by Salmonella dublin was documented in 1 cow that had arthritis. Two other cows were condemned after postmortem inspection: 1 because of pneumonia and pleuritis and the other because of vegetative endocarditis. Three carcasses were retained and later condemned because of antibiotic residues in tissues; 1 of these cows had mastitis, 1 had liver abscesses, and 1 was the cow with vegetative endocarditis. Sarcocystosis was found in 27 of 30 hearts, but other clinically important histologic lesions were observed only in liver samples. In 11 of the 30 cows, multifocal, microscopic foci of hepatitis were observed, suggesting that terminal embolic bacterial showering of the liver had occurred in these animals. Liver samples were not submitted for bacteriologic culture.

Clinical Implications—

Most recumbent cows slaughtered for edible beef are not contaminated by bacteria; however, the viscera from these animals may present a food safety danger. Efforts should be made to develop rapid tests to identify bacteremic animals at slaughter and to more fully evaluate terminal showering of viscera by bacteria in cattle at slaughter.

Free access
in Journal of the American Veterinary Medical Association

Summary

The B1 strain of Newcastle disease virus (ndv-B1), which is nonpathogenic for newly hatched chickens, killed embryos when it was used to inoculate chicken eggs at embryonation day 18. Treatment of ndv-B1 with an alkylating agent, ethylmethane sulfonate (ems) markedly reduced the pathogenicity of the virus for 18-day-old chicken embryos. Eggs inoculated with the modified virus (ndv-B1-ems) hatched, and the virus was isolated from lungs and spleen of 1-day-old chickens. The hatched chickens developed antibody to ndv and were protected against challenge exposure (at 4 weeks of age) with a highly virulent GB-Texas strain of ndv. Presence of maternal antibody to ndv in embryonating eggs did not influence the protective ability of ndv-B1-ems, which also induced protective immunity when administered to 4-week-old chickens. The 50% protective dose of ndv-B1-ems in maternal antibody-negative and -positive embryos was calculated to be 10.77 and 17.70 embryo 50% lethal doses, respectively. Results of the study indicated that ndv-B1-ems may be used as an embryo vaccine to protect chickens against Newcastle disease.

Free access
in American Journal of Veterinary Research