Use of zinc acetate to treat copper toxicosis in dogs.

Zinc acetate was used for the treatment and prophylaxis of hepatic copper toxicosis in 3 Bedlington Terriers and 3 West Highland White Terriers. Two dogs of each breed were treated for 2 years, and 1 of each breed for 1 year. A dosage of 200 mg of elemental zinc per day was required to achieve therapeutic objectives related to copper, which included a doubling of plasma zinc concentration to 200 micrograms/dl and a suppression of oral 64 copper absorption. The dosage was later reduced to 50 to 100 mg/day to avoid an excessive increase in plasma zinc concentration. The preliminary clinical results were good. Three dogs had mild to moderate active liver disease and high liver copper concentrations at the time of initiation of zinc administration. Biopsy of the liver 2 years later revealed a reduction in hepatitis and copper concentrations. One other dog without active hepatitis also had a reduction in hepatic copper concentrations over a 2-year period. All 6 dogs have done well clinically. On the basis of these findings, we believe zinc acetate to be an effective and nontoxic treatment for copper toxicosis in dogs.     

Copper-associated liver disease in Dalmatians: a review of 10 dogs (1998-2001)

This retrospective study summarizes 10 Dalmatians suspected of having hepatic copper toxicosis. Hepatic copper toxicosis can result from either a primary metabolic defect in hepatic copper metabolism or from altered hepatic biliary excretion of copper. An inherited copper-associated hepatopathy has been documented in Bedlington Terriers, and there is evidence for familial copper-associated liver disease in West Highland White (WHW) Terriers and Skye Terriers. Nine of the 10 Dalmatians in this study presented for gastrointestinal clinical signs, including anorexia and vomiting. All animals had increased alanine aminotransferase (ALT) enzyme activity, and 9 of 10 had increased alkaline phosphatase (ALP) enzyme activity. The relative increase in ALT activity was much greater than the relative increase in ALP activity, suggesting a predominantly hepatocellular rather than cholestatic liver disease. The mean hepatic copper concentration for 9 Dalmatians was 3,197 microg/g dry weight liver (dwl) (normal, <450 microg/g). In 5 of these 9 dogs, hepatic copper concentrations exceeded 2,000 microg/g dwl. Necroinflammatory alterations associated with copper-laden parenchymal cells were the notable histopathologic finding. The inflammatory infiltrate was either primarily lymphocytic or neutrophilic. Morphologic features of cholestasis generally were not prominent except in those dogs with severe pathology. These findings lend support to the hypothesis that a primary metabolic defect in hepatic copper metabolism occurs in the Dalmatian breed. The mechanism and genetic basis of this condition require further study.     

Use of 2,3,2-tetramine as a hepatic copper chelating agent for treatment of copper hepatotoxicosis in Bedlington terriers

Five Bedlington Terriers with inherited copper (Cu) hepatotoxicosis and with hepatic Cu concentrations ranging from 3,000 to 11,000 micrograms/g of dry weight (normal, less than 350 micrograms/g of dry weight) were treated daily for up to 200 days with 2,3,2-tetramine tetrahydrochloride. During treatment, no change was made in the dietary Cu intake, which ranged from 12 to 16 micrograms/g of dry diet. Concentrations of hepatic and serum Cu, iron, and zinc were determined before and at the conclusion of the treatment period. In one dog, 24-hour urinary Cu concentration was measured before and during treatment. A liver biopsy specimen obtained after treatment had significantly (P less than 0.05) reduced hepatic Cu concentration (3,282 micrograms/g of dry weight; a 54.9% reduction), compared with the pretreatment value (7,281 micrograms/g of dry weight). After treatment, there was an overall general lessening of the extent of hepatic morphologic damage. Cytochemical examination for Cu in rhodanine-stained biopsy specimens revealed decreased numbers of Cu-laden hepatic lysosomes. The mean daily urinary Cu concentration increased as much as 25-fold during 2,3,2-tetramine treatment. Hepatic iron and zinc concentrations and serum Cu concentrations remained within normal ranges after treatment. Clinical or laboratory evidence of 2,3,2-tetramine toxicosis was not detected during treatment. These findings indicated that in affected Bedlington Terriers, 2,3,2-tetramine was a safe and rapid chelating agent of hepatic Cu.     

Clinical, morphologic, and chemical studies on copper toxicosis of Bedlington Terriers.

In a study of 90 Bedlington Terriers, 68 had a defect that resulted in the accumulation of toxic excesses of copper in the liver. Concentrations of copper were 5 to 50 times that of clinically normal mongrel dogs. The bulk of this excess copper was sequestered in lysosomes. When copper concentrations exceeded 2,000 micrograms/g dry liver, progressive signs of functional and morphologic disturbance appeared as focal hepatitis, chronic active hepatitis, and ultimately cirrhosis. The disorder, which appears to be inherited, could only be diagnosed by liver biopsy. It was latent for many years in some dogs but led early in life to acute or chronic hepatic disease and death in others.     

Inherited, chronic, progressive hepatic degeneration in Bedlington terriers with increased liver copper concentrations: clinical and pathologic observations and comparison with other copper-associated liver diseases

One hundred nineteen hepatic tissue samples from 117 Bedlington Terriers were divided into 6 groups depending on the severity of histopathologic hepatic changes. Group 0 comprised dogs with microscopically normal livers. Group I dogs had copper-positive, lipofuscin-containing lysosomes present in centrilobular hepatocytes. Microfoci of hepatic necrosis, in addition to the increased numbers of the copper-positive, lipofuscin-containing lysosomes in centrilobular and periportal hepatocytes, were present in group II dogs. Group III dogs had more copper-positive, lipofuscin-containing lysosomes present translobularly and morphologic changes consistent with chronic active hepatitis. Mixed micro- or macronodular cirrhosis and translobular presence of copper-positive, lipofuscin-containing lysosomes characterized group IV dogs. Dogs in group V had massive hepatic necrosis and morphologic changes that were consistent with the changes in group III and IV dogs. Histochemical staining for copper was useful in making the microscopic diagnosis of this disease and was shown to be necessary in early diagnosis (group I) when other clinical and pathologic values associated with this syndrome were not consistently abnormal. Copper histochemical stains varied in sensitivity. Timm's silver sulfide was more sensitive for copper than was rubeanic acid, which was more sensitive than rhodanine staining. The brown pigment associated with the copper in the lysosomes was shown to be lipofuscin pigment with the aid of histochemical staining with orcein, Prussian blue, periodic acid-Schiff, and acid-fast stains together with fluorescent microscopy (excitation maxima: 365 nm; emissions: 420 + nm). Since these were positive only in later stages of the hepatic disease, they were not especially useful in its early diagnosis. The severity of the histopathologic hepatic changes was shown to increase with age and was associated with increasing hepatic copper concentration. These observations illustrate that this inherited, chronic hepatic degeneration in the Bedlington Terrier is progressive. Clinical chemical tests were diagnostically useful only in later stages of the disease. Alanine transaminase activity was of most value, but was not always abnormal, even when severe hepatic damage was present. Clinical signs of hepatic disease were seen in dogs in groups III, IV, and V. Death due to hepatic failure occurred only in dogs in groups III, IV, and V. Hemosiderin was present in increased amounts in the liver, bone marrow, spleen, and lymph nodes of affected Bedlington Terriers, indicating that a possible defect in iron metabolism and/or an increase in RBC turnover existed.(ABSTRACT TRUNCATED AT 400 WORDS)     

Copper-associated hepatopathy in a Mexican fruit bat (Artibeus jamaicensis) and establishment of a reference range for hepatic copper in bats.

Copper toxicity has been described in numerous domestic species. The characteristic lesions include hemoglobinuric nephrosis and piecemeal hepatic necrosis with bile ductular hyperplasia and portal fibrosis. Certain species, such as sheep, are prone to toxicity when exposed to copper in feed, whereas an inherent genetic defect of copper storage is present in some breeds of dogs (Bedlington Terriers, West Highland White Terriers, Doberman Pinschers). In nondomestic species, reference ranges have not been established for copper in internal organs, so the establishment of copper toxicity as a diagnosis is difficult. A case of copper toxicity in a captive Mexican fruit bat is presented. Hepatic copper levels in 16 additional bats, of at least 3 different species, were measured. To the authors' knowledge, this is the first reported case of copper toxicity in a chiropteran.     

Evaluation of haplotypes associated with copper toxicosis in Bedlington Terriers in Australia

OBJECTIVE: To evaluate the haplotype distribution associated with the copper toxicosis gene and the segregation of the mutated allele in a Bedlington Terrier population in Australia. ANIMALS: 131 Bedlington Terriers. PROCEDURE: Samples of DNA and RNA were obtained from each dog. Genetic status of each dog was evaluated by use of the DNA markers C04107; single nucleotide polymorphism (SNP), which was adjacent to exon 2 of Murr1; and a deletion marker for exon 2. A subgroup of the study population was evaluated by use of biochemical and histologic techniques to elucidate the correlation between genotype and phenotype. RESULTS: We identified a recombination between the C04107 marker and Murr1 and a variation in a nucleotide in the splice site of exon 2 in our Bedlington Terrier cohort. Furthermore, we identified a novel haplotype associated with copper toxicosis in this cohort. CONCLUSIONS AND CLINICAL RELEVANCE: Our findings indicate that the deletion of exon 2 was not the sole cause of copper toxicosis, although only exon 2 deletion of Murr1 has been responsible for copper toxicosis in Bedlington Terriers. Although we failed to find a novel mutation in our cohort, we identified an affected dog family with an intact exon 2. Furthermore, we found that an SNP in the 5' splicing site of exon 2 may or may not be associated with a novel mutation of the Murr1 gene or other genes. Loss of linkage between the C04107 marker and the Murr1 gene was also identified in a certain family of dogs.     

Copper Toxicosis in Bedlington Terriers

Copper toxicosis of Bedlington Terriers (Chronic progressive hepatitis) is a genetically transmitted disease. The typical feature of this disease is accumulation of copper in the liver tissue. The changes vary from mild hepatitis to chronic progressive hepatitis and cirrhosis.The material of this study consists of 2 cases of copper toxicosis examined at the Department of Pathology in Helsinki in the years 1980–82. Moreover a re-examination of tissue samples was made of all Bedlington Terriers examined during the years 1969–1982 at the same department. Six of the 14 examined dogs showed a positive reaction for copper in their liver tissues. The possible relationship of the examined dogs is not yet known.     

Copper toxicosis in Bedlington Terriers in the United Kingdom

This paper summarizes the clinical and laboratory data on two adult Bedlington Terriers with liver disease associated with copper toxicosis. The younger dog, at 3 years, had elevated serum levels of alanine aminotransferase and alkaline phosphatase with active parenchymal cell degeneration and hepatitis. The second dog developed chronic hepatic failure at 5 years with advanced cirrhosis. Both dogs had stainable copper granules in the liver and chemical analysis of their livers revealed elevated copper contents (1,027 and 10,728 μg/g dry weight; normal less than 300 μg/g). These are the first published cases of this inherited abnormality of copper metabolism in this breed in this country.     

Inherited copper toxicosis in Bedlington terriers

SUMMARY Chronic hepatitis and increased hepatic copper concentrations, from 1,600 to 6,361 fig/g dry tissue were found in 4 related, Australian-bred Bedlington terriers. Two dogs were asymptomatic and 2 were clinically ill with signs referable to liver dysfunction. Two dogs were treated with d-penicillamine. After one year there was no improvement in the histopathological liver changes in either dog or significant lowering of hepatic copper level in one dog.     

Iatrogenic copper deficiency associated with long-term copper chelation for treatment of copper storage disease in a Bedlington Terrier

A 9-year-old Bedlington Terrier was evaluated because of weight loss, inappetence, and hematemesis. Copper storage disease had been diagnosed previously on the basis of high hepatic copper concentration. Treatment had included dietary copper restriction and administration of trientine for chelation of copper. A CBC revealed microcytic hypochromic anemia. High serum activities of liver enzymes, high bile acid concentrations, and low BUN and albumin concentrations were detected. Vomiting resolved temporarily with treatment, but the clinicopathologic abnormalities persisted. Results of transcolonic portal scintigraphy suggested an abnormal shunt fraction. Results of liver biopsy and copper quantification revealed glycogen accumulation and extremely low hepatic copper concentration. Serum and hair copper concentrations were also low. Chelation and dietary copper restriction were tapered and discontinued. Clinical signs and all clinicopathologic abnormalities improved during a period of several months.     

Assessment of plasma carnitine concentrations in relation to ceroid lipofuscinosis in Tibetan Terriers

OBJECTIVE: To determine whether the late onset form of inherited ceroid lipofuscinosis (CL) in Tibetan Terriers is accompanied by low plasma carnitine concentrations prior to the appearance of clinical signs. ANIMALS: 129 healthy Tibetan Terriers, 12 Tibetan Terriers with CL, and 95 healthy purebred dogs of other breeds. PROCEDURE: After withholding food, blood samples were collected from all dogs into tubes containing EDTA. Blood samples were analyzed for plasma-free carnitine and acyl-carnitines concentrations. RESULTS: Neither the mean plasma total carnitine concentration nor the mean fraction of carnitine in the free form differed significantly between Tibetan Terriers with CL and healthy Tibetan Terriers. Among Tibetan Terriers and the general dog population, plasma carnitine concentration increased with age. Castrated males had an overall increase in plasma carnitine concentrations and variability, compared with sexually intact males. By comparison, plasma carnitine concentrations were not significantly different between spayed and sexually intact females. The mean plasma carnitine concentration in the Tibetan Terriers was approximately 22% higher than in the general population of healthy dogs of other breeds. CONCLUSIONS AND CLINICAL RELEVANCE: Contrary to what is seen in early onset CL in English Setters and in humans with some forms of CL, plasma carnitine concentrations are not decreased in the late-onset disorder in Tibetan Terriers. Our large-scale study establishes reference range values for plasma carnitine concentrations in dogs as functions of age and sex that will be useful in evaluating potential carnitine deficiencies in other disorders in dogs.     

Investigation on trichothecene-stimulated lipid peroxidation and toxic effects of trichothecenes in animals

Three experiments were performed with mice intoxicated with trichothecene-contamined feed or directly into the stomach. Lipid peroxidation was estimated by the TBA value from liver samples, but since such a test seldom provided reliable results, lipid hydroperoxides and total carbonyl were also analyzed. The formation of aldehydes and ketones was compared in vivo and in vitro. The same investigations were conducted on chickens, rainbow trouts and numerous fur animals suspected of chronic intoxication by trichothecenes. The vitamin A concentration was used as a parameter to detect alterations caused in chickens by trichothecenes. Our investigation provided evidence that lipid peroxidation is associated with trichothecene poisoning. The T-2 toxin, even in small concentrations, seems to induce strong lipid peroxidation. When DON and 3-AcDON were given together at a dosage of 180 micrograms/kg feed, 1 week's feeding caused clear lipid peroxidation in mice. Particular attention should be paid to the fact that mycotoxins may already be present in the feed before any experiment is conducted.     

Breed predisposition to congenital alacrima in dogs

Objective  To evaluate the clinical characteristics and breed predisposition of congenital alacrima in dogs.
Animals studied  Dogs with congenital keratoconjunctivitis sicca.
Procedures  A search of the medical records of the University of Tennessee Veterinary Teaching Hospital from 1974–2005 and the University of California–Davis Veterinary Teaching Hospital from 1986–2006 for dogs under 1 year of age with a diagnosis of keratoconjunctivitis sicca (KCS) was performed. These cases were further reviewed for dogs with a Schirmer's tear test I of ≤ 5 mm/min before 6 months of age, with no known causes for KCS, which did not respond to appropriate KCS therapy; these cases were considered to have congenital alacrima. These breeds were compared to all other breeds using the Fisher's exact test with correction for multiple comparisons.
Results  Congenital alacrima was identified in 19 dogs representing 11 breeds and mixed breeds. Yorkshire Terriers and Bedlington Terriers were statistically overrepresented compared to reference populations ( P  < 0.01 and P  = 0.04, respectively).
Conclusions  Yorkshire terriers are significantly at risk for congenital alacrima compared to other breeds. The significance of the increase in congenital alacrima in Bedlington Terriers in this study may not be clinically relevant and may be due to the small total number of dogs of this breed that presented to the both hospitals. Based on the poor response to therapy in humans with congenital alacrima, it may be prudent to offer guarded prognoses for KCS in juvenile Yorkshire terriers.     

Polymorphisms in canine ATP7B: candidate modifier of copper toxicosis in the Bedlington terrier

A COMMD1(MURR1) deletion has been reported as the cause of copper toxicosis (CT) in Bedlington terriers. Recent studies identified Bedlington terriers with copper accumulation without homozygous COMMD1 deletions. Wilson disease in humans is a copper storage disorder similar to CT caused by mutations in ATP7B, and COMMD1 has been shown to interact with the ATP7B protein. ATP7B may act as a modifier in CT, allowing for copper accumulation in Bedlington terriers with one deletion or other variations in COMMD1. In this study, ATP7B was cloned and sequence analysis conducted in a subset of Bedlington terriers from a pedigree that does not show complete association between the COMMD1 deletion and CT. Eleven polymorphisms, two in the coding region, were identified in the Bedlington terrier ATP7B gene. However, these are not unique to the Bedlington terrier and pedigree analysis suggests that ATP7B is not a modifier of COMMD1 in this subset of dogs.     

Reduction of serum triacylglycerol-rich lipoprotein concentrations in cows with hepatic lipidosis

The hepatic and serum lipid concentrations in 49 dairy cows with displaced abomasum, 7 postpartum cows fasted for 6 days, and 14 healthy postpartum cows were studied. The cows with displaced abomasums were retrospectively allotted to 2 groups: those with greater than 15% liver fat (DAHF) and those with less than 15% liver fat (DALF). Liver total lipid concentrations were high in the DAHF group, exceeding these values in the fasted cows by 30% and in the healthy and DALF cows by 63% on the average. In contrast, the liver phospholipid concentrations were low in the DAHF group, intermediate in the fasted and DALF groups and high in the healthy group. On a group basis, an inverse relationship was observed between serum and liver lipid concentrations. The serum concentrations of both total and dextran-sulfate-precipitable (DSP) lipids were high in the fasted cows and were less in the DALF and healthy cows and in the DAHF cows (lowest). The between-group differences in serum total and serum DSP concentrations of triacylglycerol, cholesterol, and phospholipid followed the same quantitative pattern as the total lipids. However, the relative difference between groups was greater for each of the DSP lipid fractions. These results support the hypothesis that severe hepatic lipidosis in cattle occurs due to impaired hepatic lipoprotein synthesis and secretion.     

Inherited copper toxicosis in the Bedlington terrier: the prevalence in asymptomatic dogs

Copper toxicosis in the Bedlington terrier is an inherited defect. This paper describes the investigation of 62 Bedlington terriers, none of which had shown any clinical signs of liver disease, in order to assess the prevalence of copper toxicosis in the breed in the United Kingdom. Twenty one (33·9 per cent) of the dogs investigated had abnormally high levels of copper in the liver. No reliable circulating haematological or biochemical parameters were found to identify those dogs with increased hepatic copper levels and the diagnosis could only be established by liver biopsy. Affected dogs had liver copper levels of between 257·5 and 2558·0 μpg per g of wet weight (1163·8 ± 164 μg/g, mean ± SEM) compared with normal dogs which had between 9·9 and 118·6 μg/g of wet weight (49·0 & 4·4 μg/g, mean ± SEM). Copper accumulation in the liver of affected dogs could also be detected on histological examination using special stains.     

Oxidant and antioxidant profile of hyperketonemic ewes affected by pregnancy toxemia

Background: Negative energy balance during late pregnancy in ewes is an important cause of hyperketonemia. Ketone bodies can generate superoxide radicals and cause oxidative stress and cellular dysfunction, as noted in cows with subclinical ketosis or in diabetic people. Objective: The aim of this study was to evaluate the role of hyperketonemia in initiating the process of lipid peroxidation. Methods: The study included 10 pregnant ewes (aged 3.5–6 years) with pregnancy toxemia, 10 clinically healthy pregnant ewes, and 10 clinically healthy nonpregnant ewes. Serum concentrations of β‐hydroxybutyrate (BHB), cortisol, and glucose, plasma activities of glutathione peroxidase, superoxide dismutase, and catalase, and plasma concentrations of thiobarbituric acid reactive substances (TBARS), markers of lipid peroxidation, and reduced glutathione were measured. Data from the 3 groups were statistically analyzed and compared. Results: Serum concentrations of BHB, cortisol, and TBARS were significantly higher in ewes with pregnancy toxemia when compared with concentrations in healthy pregnant and nonpregnant groups (P≤.05). In ewes with pregnancy toxemia, a strong positive correlation was found between concentrations of TBARS and BHB (r=.80; P=.002) and between concentrations of BHB and cortisol (r=.76; P=.005). Conclusions: Oxidative stress and lipid peroxidation are involved in the development and complications of pregnancy toxemia. An association between hyperketonemia and the products of lipid peroxidation has also been demonstrated, suggesting that ketosis is a risk factor in the development of lipid peroxidation and oxidative stress in ewes affected by pregnancy toxemia.     

The effect of the source and dosage of dietary Cu on redox status in rat tissues

The aim of this experiment was to investigate whether the amount of Cu added to the diet of rats can be reduced without adversely affecting the antioxidant status of tissues and growth, and whether copper nanoparticles can be used for this purpose. For four weeks, four experimental groups of rats were fed diets with two dosages of added Cu (standard—6.5 or 3.25 mg/kg) in two forms (standard—CuCO₃ or copper nanoparticles). Replacing the CuCO₃ supplement with CuNPs resulted in a decreased lung weight and an increased Cu content in brain, kidney and lung, intensification of lipid peroxidation processes, and weakened antioxidant defence in the lungs and kidneys. This treatment also reduced the Cu content in heart, level of lipid oxidation in the liver and testes and improved antioxidant defence in the brain. Reducing the addition of Cu to the diet from 6.5 to 3.25 mg/kg reduced lung weight and increased lipid peroxidation in the liver, heart and lungs, and also weakened antioxidant defence in the lungs and testes. This treatment also weakened the lipid peroxidation process in the spleen, small intestine and brain and strengthened the antioxidant defence of the brain and kidneys. In conclusion, replacing CuCO₃ with CuNPs and reducing the level of Cu in the diet of rats has a particularly unfavourable effect on the respiratory system, causing adverse changes in the lungs. However, these treatments have a clearly positive effect on the redox status of the liver and brain.