Etiopathologic findings of canine hypothyroidism.

The causes of canine hypothyroidism are varied, but most cases result from irreversible acquired thyroid pathologic changes and only a small proportion arise from congenital anomalies of the thyroid gland or pituitary. Of primary thyroid failure, at least half is the result of immune-mediated thyroiditis. Recent research has focused on the genetics and immunology of canine thyroid disease, adding to what is known from experimental and human studies. Epidemiologic and diagnostic laboratory studies continue to provide information on contributing factors and raise questions for future research directions. Serum antibodies against thyroid components are common in thyroid pathologic conditions and dysfunction, and understanding their properties and frequency is important in the interpretation of thyroid diagnostic test results.     

Drug choice and therapeutic drug monitoring in the management of canine primary epilepsy

Therapeutic drug monitoring is an underutilised resource in the management of canine primary epilepsy. Many of the anti-epileptic drugs, including phenobarbitone, have variable pharmacokinetic profiles in different dogs, with each individual animal showing variable rates of absorption, distribution, metabolism and excretion. This results in variable serum drug concentrations with the same oral dose. Many clinicians interpret this situation as therapeutic failure and classify these patients as refractory to treatment. By measuring blood concentrations of drugs at appropriate times, it is possible to explain the efficacy or failure of treatment, and also to prevent serum concentrations from reaching toxic levels. By analysing paired samples, key pharmacokinetic parameters may be calculated for each patient and a profile for the disposition of the drug obtained. Individual optimal drug dosage can be calculated for each patient at little cost to the pet owner.     

Conditions associated with canine hypothyroidism.

Careful review of the literature regarding clinical signs caused by hypothyroidism in dogs has shown that some assumptions regarding the relation of hypothyroidism to other conditions are based on anecdotal evidence. Cutaneous manifestations are present in most hypothyroid dogs, but the specific abnormalities and breed variations remain to be clearly defined. Decreased metabolic rate manifested by obesity and lethargy is also common. Neurologic manifestations, although uncommon, clearly occur in hypothyroid dogs. Cardiac abnormalities seem to be common, but their clinical significance is questionable. The only consistent hematologic abnormality that occurs in hypothyroid dogs is anemia; evidence for acquired von Willebrand's disease or other bleeding disorders is negligible. Reproductive dysfunction secondary to hypothyroidism is unlikely to occur in male dogs, and there is no evidence to support abnormalities in female dogs. The relation of megaesophagus, laryngeal paralysis, ocular abnormalities, and gastrointestinal disorders with hypothyroidism remains to be established. Future research into canine hypothyroidism may serve to convert dogma into a more clear understanding of the manifestations and pathophysiologic findings of this common endocrinopathy.     

Increased serum concentrations of adiponectin in canine hypothyroidism

Serum concentrations of adiponectin were compared between sex-matched hypothyroid (n = 18) and euthyroid (n = 18) client-owned dogs with comparable ages and body condition scores (BCS). Concentrations of adiponectin (mean; 95% confidence interval) were significantly (P < 0.01) higher in hypothyroid (17.2 µg/mL; 12.1–20.5 µg/mL) than healthy (8.0 µg/mL; 5.6–11.4 µg/mL) dogs following adjustment for potential confounders (BCS, age and sex). Serum concentrations of adiponectin were significantly negatively associated with concentrations of total thyroxine (P <0.05) and positively correlated with concentrations of cholesterol (r = 0.6, P <0.01) in hypothyroid dogs. In conclusion, this study demonstrated increased serum concentrations of adiponectin in dogs with hypothyroidism. Suggestive of the presence of resistance to adiponectin that could have contributed to development of hyperlipidemia and insulin resistance in these dogs or alternatively, could be a consequence of these metabolic alterations.     

Increased serum leptin and insulin concentrations in canine hypothyroidism

Serum concentrations of leptin and insulin were compared between gender-matched hypothyroid (n=25) and healthy (n=25) client-owned dogs within comparable age and body condition score (BCS) ranges. Fasted blood samples were collected from each dog and analysed for glucose, cholesterol, triglyceride, leptin and insulin concentrations. Leptin and insulin concentrations were significantly higher in the hypothyroid compared to normal dogs (P=0.006 and P=0.001, respectively) following adjustment for potential confounders. A nearly significant (P=0.051) interaction with BCS was found in the association between hypothyroidism and leptin. Leptin concentrations were significantly higher in hypothyroid dogs compared to normal dogs, in separate analyses for BCS 6 (P=0.036) and 7 (P=0.049). There was no significant difference in glucose concentration between the hypothyroid and normal groups (P=0.84) following adjustment for BCS. This study showed that canine hypothyroidism is associated with increased serum leptin and insulin concentrations, neither of which may be attributed to obesity alone.     

Epidemiological, clinical, haematological and biochemical characteristics of canine hypothyroidism

Hypothyroidism was diagnosed in 50 dogs and excluded in 86 dogs suspected of hypothyroidism, on the basis of the results of bovine thyrotropin response tests. Breed, pedigree, sex or neutering status did not significantly influence the likelihood of the dogs being hypothyroid. The hypothyroid dogs were significantly older than the non-hypothyroid dogs referred to the University of Glasgow during the same period. However, when dogs under two years of age were excluded from the statistical analyses there was no significant difference in age between the two groups. The most common clinical characteristics associated with hypothyroidism were metabolic signs (84 per cent of cases), particularly lethargy (76 per cent), obesity or weight gain (44 per cent), and exercise intolerance (24 per cent); and dermatological abnormalities (80 per cent), including alopecia (56 per cent), poor coat quality (30 per cent) and hyperpigmentation (20 per cent). When compared with the laboratory reference limits the most common biochemical and haematological abnormalities were increased concentrations of triglycerides (88 per cent), cholesterol (78 per cent), glucose (49 per cent), and fructosamine (43 per cent), and increased activities of creatine kinase (35 per cent), and decreased concentrations of inorganic phosphate (63 per cent), and a low red blood cell count (40 per cent). When compared with reference limits derived from the euthyroid dogs the most common abnormalities were increased concentrations of gamma-glutamyltransferase (21 per cent), cholesterol (18 per cent), and aspartate aminotransferase (15 per cent) and a decreased red blood cell count (29 per cent), and decreased neutrophils (18 per cent) and decreased activity of creatine kinase (15 per cent). Assessment of cholesterol, creatine kinase, aspartate aminotransferase, gamma-glutamyltransferase, and red blood cell and neutrophil counts may be particularly useful in distinguishing hypothyroid dogs from euthyroid animals with similar clinical signs.     

Effectiveness of a therapeutic drug monitoring service as an aid to the control of canine seizures

The results presented were derived from an anticonvulsant monitoring service, provided for two years to practising veterinary surgeons, in which samples of serum were taken from dogs treated with either primidone or phenobarbitone. Of the 19 patients assessed, 13 were controlled after the recommended changes in dose had been made. Of the six patients not completely controlled after changes in dose, four had a much lower incidence of seizures but two did not respond to treatment in spite of having high serum phenobarbitone levels. There were large variations between the doses of anticonvulsant drugs required to reach therapeutic serum levels; these variations underlined the value of routine monitoring for improving the control of canine seizures.     

Tryptic peptides of canine thyroglobulin reactive with sera of patients with canine hypothyroidism caused by autoimmune thyroiditis

Canine thyroglobulin (cTg) was treated with trypsin at a ratio of trypsin to cTg of 1:100 (w/w). Tryptic peptides of cTg were analysed by Western immunoblotting for their reactivity to serum thyroglobulin autoantibodies (TgAA) from patients with TgAA-positive hypothyroidism and normal individuals. The sera of patients with TgAA-positive hypothyroidism reacted with several peptides: 43, 32.5 and 31 kDa; the sera of normal individuals did not bind these tryptic peptides. Some of the TgAA-positive sera of patients reacted with 25 kDa peptide in addition to three tryptic peptides above. This experiment was the first report about antigenic epitopes of cTg. These small tryptic peptides recognized by TgAA may be related with the induction of TgAA and may be useful as markers for autoimmune thyroid diseases in dog.     

犬关节炎的治疗

犬关节炎多发于青年犬,后肢较重。多因遭雨淋,久卧湿地、水泥地或冷天夜卧圈外所致。病状:患犬病初走路不能持久,多卧少立,逐渐走路跛行、摇摆,继之跗关节肿大疼痛,不让触摸,如果体温升高还会减食或停食。检查:单纯关节炎多体温39℃以内,少数39.5℃以上,减食,散放四肢不协调,停走即卧下,跗关节增温,微显大,犬躲避检查。治疗:对体温39℃以下饮食变化不大的病犬,两后肢跗关节上5厘米浅层肌肉注射庆大霉素40万、地塞米松10毫克、30%安乃近10毫升混合,两后肢分别注射,1天1次,连用3～4次。如果犬个头大,四肢都疼,应在两前肢腕关节上5厘米,两后肢…     

犬癫痫病的治疗体会

犬癫痫病是一种以突然发作为特征的大脑功能紊乱。目前认为发作是来源于脑部病灶的阵发性异常高频放电,并向发病周围组织扩散,导致脑组织的广泛兴奋,从而出现特有的惊厥症状。     

Evaluation of serum free thyroxine and thyrotropin concentrations in the diagnosis of canine hypothyroidism

Canine thyroid-stimulating hormone (cTSH), total thyroxine (T4) and free T4 by equilibrium dialysis (fT4d) were measured in serum samples from 107 dogs with clinical signs suggestive of hypothyroidism in which the diagnosis was either confirmed (n = 30) or excluded (n = 77) by exogenous TSH response testing. Median serum total T4 and fT4d concentrations were significantly lower and cTSH significantly higher (P < 0.001) in hypothyroid compared with euthyroid dogs. Differential positive rate analysis determined optimal cut-off values of less than 14.9 nmol/litre (total T4), less than 5.42 pmol/litre (fT4d), greater than 0.68 ng/ml (cTSH), less than 17.3 (T4 to cTSH ratio), and less than 7.5 (fT4d to cTSH ratio) for hypothyroidism. These had a sensitivity and specificity of 100 and 75.3 per cent, 80 and 93.5 per cent, 86.7 and 81.8 per cent, 86.7 and 92.2 per cent, and 80 and 97.4 per cent, respectively, for diagnosing hypothyroidism. Corresponding areas under the receiver operating characteristic curves were 0.92, 0.93, 0.87, 0.93 and 0.93. Unexpectedly low cTSH values in hypothyroid dogs may have resulted from concurrent non-thyroidal illness. Unexpectedly high serum cTSH values in the euthyroid dogs might have resulted from recovery from illness or concurrent potentiated sulphonamide therapy. Measurement of endogenous cTSH concentration is a valuable diagnostic tool for canine hypothyroidism if used in association with assessment of T4. Estimation of fT4d added only limited additional information over total T4 measurement.     

Laboratory tests for diagnosing and monitoring canine leishmaniasis

Although several reviews on canine leishmaniasis have been published, none thoroughly described clinicopathologic abnormalities and their clinical usefulness. The aim of this review was to provide information concerning current diagnostic tests relevant for clinical pathologists and from a practical perspective. Specifically, in canine leishmaniasis, nonregenerative normocytic normochromic anemia, thrombocytopenia, or leukogram changes may be present. Clinical chemistry and urinalysis may indicate renal dysfunction (azotemia, decreased urine specific gravity, proteinuria) and an inflammatory/immune response (increased acute phase proteins [APP] or α₂‐ and/or γ‐globulins). Although a potential gammopathy is usually polyclonal, it may also appear oligo‐ or monoclonal, especially in dogs coinfected by other vector‐borne pathogens. When lesions are accessible to fine‐needle aspiration (lymphoadenomegaly, nodular lesions, joint swelling), cytology is strongly advised, as the presence of Leishmania amastigotes in a pattern of pyogranulomatous inflammation or lymphoplasmacytic hyperplasia is diagnostic. If the cytologic pattern is inconclusive, the parasite should be identified by histology/immunohistochemistry or PCR on surgical biopsies. Alternatively, cytology and PCR may be performed on bone marrow samples where amastigotes, along with erythroid hypoplasia, myeloid hyperplasia, plasmacytosis, or secondary dysmyelopoiesis can be observed. Dogs with overt leishmaniasis generally have high antibody titers, while low titers predominate in immunologically resistant infected dogs or in exposed dogs with no parasite confirmation. Quantitative serology is recommended in clinically suspect dogs as high‐titer antibodies titers may confirm the clinical diagnosis. In confirmed and treated dogs, renal function and inflammatory/immune response variables should be periodically monitored.     

犬瘟热的综合疗法与体会

犬瘟热是由副粘病毒科的犬瘟热病毒所引起的一种犬科动物的烈性传染病。其特点是传播速度快,流行范围广,死亡率高。另     

犬特应性皮炎及其治疗药物的研究进展

犬特应性皮炎是一种具有遗传倾向的过敏性皮肤病。由于近年来我国养犬数量不断增加,犬特应性皮炎成为宠物临床上的常见疾病,严重危害了宠物犬的身体健康。该病病因复杂,大致可概括为遗传因素、环境因素、皮肤屏障功能失调、免疫功能失调和微生物菌群失调五个方面,且由于其临床症状与其他过敏反应、炎症反应相似,难以确诊,需要通过多种临床反应共同判定。随着小动物诊疗的不断发展,犬特应性皮炎治疗在以往基础疗法上又增加了使用抗炎止痒药物、JAK通路抑制药物、生物制品药物和PED-4 选择性抑制剂等治疗方式。本文综述了近年来犬特应性皮炎的病因、临床症状、诊断方法和治疗方法方面的研究进展,以期为犬特应性皮炎的治疗提供借鉴和参考。