Treatment of lead poisoning in wild geese.

Twenty-seven wild geese (Anser albifrons) suffering from lead poisoning caused by ingestion of lead shot were treated with disodium calcium ethylenediaminetetraacetate. The concentration of lead in blood ranged from 0.4 to 23.0 micrograms/ml, with a mean concentration of 5.6 micrograms/ml. In 22 of the birds, 1 to 48 lead pellets (mean, 10.5 pellets/bird) were seen on radiographs of their gizzards. Eleven of 27 birds recovered 3 to 8 weeks after the initiation of treatment. In the birds that recovered, the lead pellets were rapidly eroded as the birds recovered their appetites in response to treatment, and disappeared radiographically between treatment days 17 and 52. The birds that did not survive died within 4 weeks, despite decreased concentrations of lead in blood. Of these 16 birds, 15 had radiographic evidence of impaction of the proventriculus at the first examination and no evidence of resolution of the impaction at the time of death. In contrast, only 2 of the 11 geese that recovered had impaction of the proventriculus at the time of admission. Thus, the condition of the proventriculus seems to be the first consideration to evaluate in the prognosis of lead poisoning in geese.     

Two‐Year Follow‐Up Magnetic Resonance Imaging and Spectroscopy Findings and Cerebrospinal Fluid Analysis of a Dog with Sandhoff's Disease

A 13‐month‐old female Toy Poodle was presented for progressive ataxia and intention tremors of head movement. The diagnosis of Sandhoff's disease (GM2 gangliosidosis) was confirmed by deficient β‐N‐acetylhexosaminidase A and B activity in circulating leukocytes and identification of the homozygous mutation (HEXB: c.283delG). White matter in the cerebrum and cerebellum was hyperintense on T2‐weighted and fluid‐attenuated inversion recovery magnetic resonance images. Over the next 2 years, the white matter lesions expanded, and bilateral lesions appeared in the cerebellum and thalamus, associated with clinical deterioration. Magnetic resonance spectroscopy showed progressive decrease in brain N‐acetylaspartate, and glycine‐myo‐inositol and lactate‐alanine were increased in the terminal clinical stage. The concentrations of myelin basic protein and neuron specific enolase in cerebrospinal fluid were persistently increased. Imaging and spectroscopic appearance correlated with histopathological findings of severe myelin loss in cerebral and cerebellar white matter and destruction of the majority of cerebral and cerebellar neurons.     

Identification of heat shock protein 70 in canine reticulocytes and mature erythrocytes

In the present study, we demonstrated that heat shock protein 70 (Hsp70) was present in both canine reticulocytes and mature erythrocytes, and that the canine Hsp70 in reticulocytes was decreased along with the maturation of the cells into erythrocytes. These results suggest that the Hsp70 in canine reticulocytes might act as a chaperone to remove unnecessary proteins during reticulocyte maturation. We also demonstrated that Hsp70 was present in exosomes from reticulocytes during their maturation in in vitro culture. Furthermore, the concentration of Hsp70 in reticulocyte membranes was increased in proportion to an increase of the protein in exosomes until 48 hours after the incubation of reticulocytes in vitro. At 96 hours of the incubation, however, only a trace amount of Hsp70 was detected in the membrane, while a large amount of the protein was present in the exosomes. These results suggest that Hsp70 in canine reticulocytes might play an important role for exosome formation in reticulocytes, resulting in the maturation of the cells.     

Heinz body hemolytic anemia with eccentrocytosis from ingestion of Chinese chive (Allium tuberosum) and garlic (Allium sativum) in a dog

A 4-year-old, intact male miniature schnauzer was presented with anorexia. The dog had ingested some Chinese steamed dumplings 2 days before, which contained Chinese chive (Allium tuberosum) and garlic (Allium sativum). Hematological examinations revealed severe Heinz body hemolytic anemia with eccentrocytosis and an increased concentration of methemoglobin, which was thought to result from oxidative damage to erythrocytes by constituents in these Allium plants. In this case, eccentrocytosis was a hallmark finding and could be detected easily, suggesting that this hematological abnormality is useful in diagnosing Allium plant-induced hemolysis.     

Vaccine efficacy of a cell lysate with recombinant baculovirus-expressed feline infectious peritonitis (FIP) virus nucleocapsid protein against progression of FIP

The Type II feline infectious peritonitis virus (FIPV) infection of feline macrophages is enhanced by a monoclonal antibody (MAb) to the S protein of FIPV. This antibody-dependent enhancement (ADE) activity increased with the MAb that showed a neutralizing activity with feline kidney cells, suggesting that there was a distinct correlation between ADE activity and the neutralizing activity. The close association between enhancing and neutralizing epitopes is an obstacle to developing a vaccine containing only neutralizing epitopes without enhancing epitopes. In this study, we immunized cats with cell lysate with recombinant baculovirus-expressed N protein of the Type I FIPV strain KU-2 with an adjuvant and investigated its preventive effect on the progression of FIP. Cats immunized with this vaccine produced antibodies against FIPV virion-derived N protein but did not produce virus-neutralizing antibodies. A delayed type hypersensitivity skin response to N protein was observed in these vaccinated cats, showing that cell mediated immunity against the FIPV antigen was induced. When these vaccinated cats were challenged with a high dose of heterologous FIPV, the survival rate was 75% (6/8), while the survival rate in the control group immunized with SF-9 cell-derived antigen was 12.5% (1/8). This study showed that immunization with the cell lysate with baculovirus-expressed N protein was effective in preventing the progression of FIP without inducing ADE of FIPV infection in cats.     

Relation between reticulocyte count and characteristics of erythrocyte 5'-nucleotidase in dogs,cats, cattle and humans

To examine substrate specificity and susceptibility to lead, erythrocyte 5'-nucleotidase was measured in dogs, cats, cattle and humans, and its relationship to the reticulocyte count in these species was determined. The reticulocyte count in dogs was similar to that in humans, but the count in cats was higher than that in humans. Reticulocytes were not observed in cattle. The activities of canine erythrocyte 5'-nucleotidase measured using cytidine and uridine 5'-monophosphates, which are preferentially catalyzed by one of the human pyrimidine 5'-nucleotidase isozymes (P5N-I), were similar to those of the human enzyme. The canine enzyme preferentially catalyzed thymidine 3'-monophosphate, which is catalyzed only by human P5N-II, more strongly than the human enzyme. This suggests that canine erythrocytes have two isozymes similar to human P5N-I and P5N-II, and a higher P5N-II-like activity than human erythrocytes. Feline erythrocytes had the highest level of P5N-I-like activity among the species examined, and the bovine enzymic activities including those of P5N-I and II were the lowest among these species. According to these observations, the reticulocyte count was approximately proportional to the P5N-I-like activity in these species. Therefore, the P5N-I-like activity may be involved in the morphological maturation of mammalian erythrocytes. The canine and feline erythrocytes had markedly high activity and preferentially catalyzed purine 5'-monophosphate suggesting the presence of a purine-specific 5'-nucleotidase as in human erythrocytes. In addition, the canine and feline P5N-I-like activity showed less susceptibility to lead than the human P5N-I. This may be a reason why there are few case reports of lead-induced anemia in dogs and cats.     

Clinical and clinico-pathologic characteristics of Shiba dogs with a deficiency of lysosomal acid beta-galactosidase: a canine model of human GM1 gangliosidosis

The present study was conducted to determine the clinical and clinico-pathologic characteristics of Shiba dogs with GM1 gangliosidosis, which is due to an autosomal recessively inherited deficiency of lysosomal acid beta-galactosidase activity. Clinical and clinico-pathological features were investigated in 10 homozygous Shiba dogs with GM1 gangliosidosis. The age at onset was 5 to 6 months and the dogs manifested progressive neurologic signs including loss of balance, intermittent lameness, ataxia, dysmetria and intention tremor of the head. The dogs were unable to stand by 10 months of age due to a progression of ataxia and spasticity in all limbs. Corneal clouding, a visual defect, generalized muscle rigospasticity, emotional disorder and a tendency to be lethargic were observed at 9 to 12 months. The dogs became lethargic from 13 months of age. The survival period seemed to be 14 to 15 months. As a clinico-pathologic feature, lymphocytes with abnormally large vacuoles were observed in peripheral blood (30 to 50% of total lymphocytes) through the lifetime of the dogs. The clinical and clinico-pathologic characteristics of this animal model are useful for not only the development and testing of potential methods of therapy, but also the diagnosis of affected homozygous Shiba dogs in veterinary clinics.     

Increased concentration of GM1-ganglioside in cerebrospinal fluid in dogs with GM1- and GM2-gangliosidoses and its clinical application for diagnosis.

GM1- and GM2-gangliosidoses are lethal lysosomal diseases that are caused by a defect of acid hydrolases, resulting in the intralysosomal accumulation of the specific physiological substrates, GM1- and GM2-gangliosides, respectively. In the present study a method for the diagnosis of canine GM1-gangliosidosis was established using canine cerebrospinal fluid (CSF). The concentration of GM1-ganglioside in CSF was determined by thin-layer chromatography-enzyme immunostaining using biotin-conjugated cholera toxin B, which specifically binds with GM1-ganglioside. The concentration of CSF GM1-ganglioside was increased in Shiba dogs with GM1-gangliosidosis, and the increased level was approximately proportional to the age of the dogs. The concentration was high in the affected dog even at 5 months of age, when Shiba dogs with GM1-gangliosidosis first manifest neurologic signs. In addition, the concentration of CSF GM1-ganglioside in a dog with the GM2-gangliosidosis 0 variant (Sandhoff disease) was also 7 times the normal level. From these results it was concluded that this laboratory technique enables a definitive and early diagnosis of canine GM1-gangliosidosis even if tissues and organs cannot be obtained. However, because GM1-ganglioside can also be elevated in cases of GM2-gangliosidosis, it is necessary to assay for specific enzyme deficiencies to definitively separate GM1- from GM2-gangliosidosis.     

Comparison of polymerase chain reaction-restriction fragment length polymorphism assay and enzyme assay for diagnosis of G(M1)-gangliosidosis in Shiba dogs.

In the present study, diagnostic methods for canine G(M1)-gangliosidosis were examined by comparing a DNA mutation assay with an enzyme assay. Sixty-two Shiba dogs of a pedigree with G(M1)-gangliosidosis were differentiated into 3 genotypes, i.e., normal, heterozygous, and homozygous affected dogs, using a DNA mutation assay, which consists of polymerase chain reaction amplification and the determination of restriction fragment length polymorphisms. The beta-galactosidase activity in leukocytes, umbilical cords, and plasma was measured using 4-methylumbelliferyl beta-D-galactoside and p-nitrophenyl beta-D-galactoside as artificial substrates and compared among the 3 genotypes. The results showed that it was possible to identify homozygous dogs with the enzyme assay using leukocytes and umbilical cords. When using leukocytes, heterozygous carriers could be differentiated from normal dogs in many cases. However, the use of the DNA mutation assay is essential for a complete determination of heterozygous carriers because of the overlap in the distribution of enzyme activity between these 2 groups. When umbilical cords were used, heterozygous carriers could not be differentiated from normal dogs because of no significant difference in enzyme activity between these 2 groups. The beta-galactosidase activity in plasma was not applicable to the diagnosis and genotyping of G(M1)-gangliosidosis in Shiba dogs.