Membranous glomerulonephritis in the Iberian lynx (Lynx pardinus)

The Iberian lynx is the most endangered felid species in the world, confined nowadays to two isolated metapopulations in the southwest of Spain, where less than 200 individuals survive. Little is known about the diseases that affect these animals in the wild or in captivity. Kidney samples from necropsies of 27 Iberian lynxes, wild and captive, were examined by histopathology, immunohistochemistry (IgG, IgM, IgA, laminin, type IV collagen, and fibronectin), electron microscopy (n=8) and immunogold labelling for IgM, IgG and IgA in one case, in order to characterize the glomerulopathy prevalent in this species. Urinalyses from records were available for 9 of the necropsied animals and blood and urine samples from 23 free ranging and captive Iberian lynxes were prospectively obtained in order to evaluate the renal function of the living population. A focal, diffuse membranous glomerulonephritis (MGN) that progressed with age was diagnosed in all but one of the animals in different stages not associated to concurrently known infectious diseases. Positive immunoexpression of IgM and IgG was observed in the glomerular capillary basement membranes and intramembranous electron-dense deposits, compatible with immune complexes (ICs) were seen with electron microscopy. The immunogold labelling was also positive for IgM and IgG in the electron-dense areas. The serum biochemistry and urinalyses also revealed signs of mild chronic kidney disease in 16 of the 23 animals evaluated. In conclusion, the membranous glomerulopathy affecting the Iberian lynx is a progressive disease of immune origin. We postulate a possible genetic predisposition towards the disease, enhanced by inbreeding and a possible connection to an immune-mediated systemic disease.     

Disease threats to the endangered Iberian lynx (Lynx pardinus)

The Iberian lynx, (Lynx pardinus), is the most endangered felid in the world. To determine whether sympatric carnivores are reservoirs of pathogens posing a disease risk for the lynx, evidence of exposure to 17 viral, bacterial and protozoan agents was investigated in 176 carnivores comprising 26 free-living lynx, 53 domestic cats, 28 dogs, 33 red foxes (Vulpes vulpes), 24 Egyptian mongooses (Herpestes ichneumon), 10 common genets (Genetta genetta) and 2 Eurasian badgers (Meles meles) in the areas inhabited by the last two populations of Iberian lynx, both in Andalusia (South-Western Spain).The results indicated that the lynx had low rates of contact with viral pathogens, with one seropositive finding each for feline leukemia virus, parvovirus and canine adenovirus-1, whereas contact with bacteria and protozoa appeared more frequent. Active infections with parvovirus, Ehrlichia spp., Mycobacterium bovis, Leptospira interrogans and Cytauxzoon spp. were confirmed. In contrast, 53% of the domestic cats were exposed to some infectious agent (prevalence range 4.5–11.4%). Antibodies to canine distemper virus and parvovirus were frequently found in dogs (32% and 42%, respectively) and foxes (30% and 12%). Past or present infections with parvovirus, Ehrlichia spp., Chlamydophila spp., M. bovis, Salmonella enterica, L. interrogans, Toxoplasma gondii, and Neospora caninum were also detected in these and other species surveyed.Questionnaires to owners revealed that 14% of the dogs but none of the cats had been vaccinated, and no cat had been neutered. Based on the apparent absence of acquired immunity of the lynx against infectious agents, the frequent detection of agents among sympatric carnivores, and the reported lack of immunocompetence of the Iberian lynx, a disease outbreak among the local abundant carnivores may pose a serious disease risk for lynx conservation.     

Helminth parasites in faecal samples from the endangered Iberian lynx (Lynx pardinus)

The Iberian lynx is the most endangered felid in the world. Enteropathogens may threaten its survival, and therefore we analysed faecal samples from 66 different individuals (37 males and 29 females), the largest population representation studied to date. The samples were obtained from November 2005 to October 2008 in the two areas where the Iberian lynx survives: Sierra Morena and Do?ana (Andalusia, southern Spain). A total of 56.1% samples were parasitized with at least 6 species of helminths, including two cestodes (Hymenolepis spp. and Taenia spp.) and four Nematodes (Ancylostoma spp., Toxocara spp., Toxascaris leonina, and Capillaria sp.). In this work, the presence of Hymenolepis is reported for the first time in Lynx pardinus. The relevance of our findings is discussed focussed on the conservation of this endangered felid.     

Histopathological and immunohistochemical findings in lymphoid tissues of the endangered Iberian lynx (Lynx pardinus)

The Iberian lynx (Lynx pardinus) is the most threatened wild feline in the world. Little is known about the diseases and pathology that affect this animal. The aim of this study was to evaluate the histopathological status of the peripheral lymphoid tissues and thymus of Iberian lynxes necropsied between 1998 and 2003. Seventeen animals including females (n=8) and males (n=9), age range of 10 months to 16 years, with different causes of death were histopathologically and immunohistochemically (anti-CD3, CD79, MAC387, CD68) studied. Feline immunosuppressive virus laboratorial tests were negative. Five individuals presented neoplasia and/or tuberculosis. All animals presented some degree of both B and T cells depletion in peripheral lymphoid tissues and follicular hyalinosis in the center of depleted follicles. A viral origin of the lymphoid depletion is postulated although other causes (inbreeding, stress, toxic) are not ruled out. The loss of the effectiveness of the immune system increases the vulnerability of the critically endangered Iberian lynx to pathogens.     

Detection of Feline leukemia virus in the endangered Iberian lynx (Lynx pardinus).

Feline retroviruses are rarely reported in lynx species. Twenty-one Iberian lynx (Lynx pardinus) blood and tissue samples collected from Do?ana National Park and Los Villares (Sierra Morena) in southern Spain during 1993-2003 were analyzed by polymerase chain reaction to amplify nucleic acids from feline retroviruses. Six samples were positive for Feline leukemia virus (FeLV), but no samples tested positive for Feline immunodeficiency virus. The BLAST analysis indicated that 5 of the 6 sequences were closely related to FeLV strain Rickard subgroup A, whereas 1 sequence was identical to FeLV. To the authors' knowledge, this is the first report of FeLV in the endangered Iberian lynx.     

Seasonal Profiles of Ovarian Activity in Iberian lynx (Lynx pardinus) Based on Urinary Hormone Metabolite Analyses

The Iberian Lynx Ex-Situ Conservation Programme is an essential part of a co-ordinated action plan to conserve the most endangered felid species of the world. Successful captive breeding demands reliable methods for reproduction monitoring including reliable non-invasive pregnancy diagnosis. During a 3-year study, urine samples from six captive Iberian lynx females were obtained (one non-pregnant, one pseudo-pregnant and 11 pregnant cycles). Progesterone, pregnanediol and oestradiol were determined in urinary extracts and relevant urinary oestrogen metabolites were characterized by high-performance liquid chromatography (HPLC). Urinary progestins did not follow the typical pregnancy-related course of felids. In the lynx, we failed to demonstrate an urinary progestin elevation during pregnancy. In contrast, urinary oestrogens increased from 3.8 ± 0.6 to 8.6 ± 0.5 ng/mg creatinine (p < 0.001) during the pregnancy. A comparison of pseudo-pregnant with pregnant cycles revealed a further increase of oestrogens caused by implantation (p < 0.05). In one female, which refused to mate, no difference was estimated between oestrogens levels during the breeding and non-breeding seasons. Almost 10-fold higher oestrogen concentrations were measured in urines of females that shared enclosures with males. HPLC analysis of oestrogens in urine samples collected from Iberian lynx during the pregnancy revealed that lynx urine is composed of two polar oestrogen metabolites in addition to oestrone and minor amounts of oestradiol. Oestrone was detectable in all urinary extracts (8–12% of metabolites), whereas oestradiol was elevated only during late pregnancy (18%). Thus, seasonal luteal activity in Iberian lynx can be monitored by urinary oestrogens. The increase of urinary oestradiol during late pregnancy might indicate an oestradiol secretion by the lynx placenta.     

Tooth resorption in the Swedish Eurasion lynx (Lynx lynx)

The etiology of tooth resorption in the domestic cat remains unknown. The high prevalence and progressive nature of the disease complicates defining healthy control groups. In order to evaluate the possible influence of various life style changes on the prevalence of tooth resorption, healthy control groups are a prerequisite. This paper presents a prevalence study for tooth resorption in a free-ranging wild felidae population. Skulls from 46 free-ranging Eurasian lynx (Lynx lynx) were examined. The age of the animals had previously been estimated based on cementum annuli in the maxillary right canine tooth. The dental examination included both dental probing and radiographic imaging. Complicated fractures of the canine teeth were found in 9/46 (19.5%) skulls. In one fractured canine, apical root resorption and periapical lucency was detected. The root resorption was attributed to inflammatory resorption as a consequence of the initial dental trauma and necrotic pulp. No signs of tooth resorption were found in the remaining teeth. Supernumerary roots were detected in 18/46 skulls (39.1 %). Supernumerary "peg" teeth caudal to the mandibular first molar tooth were detected in 6/46 (13.0%) skulls. Although further studies on dental ultra-structure are needed, the Swedish Eurasian lynx may, in the future, be useful as a healthy comparative model for studies on the etiopathogenesis of tooth resorption in the domestic cat.     

Benign giant cell tumour of tendon sheaths in a European Lynx (Lynx lynx)

The histological, histochemical, immunohistochemical and ultrastructural features of a benign giant cell tumour (BGCT) of tendon sheaths in a 12-year-old male European lynx (Lynx lynx) are reported herein. The neoplastic mass involved the subcutaneous and inter-muscular tissues of the first, second, third and fourth digit of the left forelimb, from the phalanxes up to the carpus. The tumour appeared as a grey-whitish tissue mottled with darker areas, along with several scattered foci of orange colour. Histologically, the lesion consisted of a mixed population of numerous, multinucleated giant cells and epithelioid or spindle-shaped mononuclear cells embedded in a loose, highly vascular stroma. Neoplastic cells lined cleft formations and synovial-like projections into cystic spaces. No osteoid matrix could be detected. Haemorrhage and necrosis were also observed. The mononuclear and the giant cells were tartrate-resistant acid phosphatase and periodic acid-Schiff positive, being also immunohistochemically reactive for lysozyme and vimentin, with a few cells showing immunopositivity also for alpha-1-antitrypsin. Ultrastructurally, histiocyte-like cells, fibroblast-like cells and multinucleated giant cells were observed, but no virus-like particles could be detected in any of the above cell types. The BGCT of tendon sheaths, a fairly uncommon neoplasm in animals, has not been previously reported in the lynx.     

Plasma biochemical reference intervals for koi

OBJECTIVE: To assess reproducibility of an in-house tabletop biochemical analyzer for measurement of plasma biochemical analytes and establish reference intervals in adult koi. DESIGN: Prospective study. ANIMALS: 71 healthy adult koi. PROCEDURES: Plasma was analyzed for concentrations or activities of albumin, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, bile acids, BUN, calcium, cholesterol, creatine kinase, gamma-glutamyltransferase, globulin, glucose, K, Na, P, total bilirubin, total protein, and uric acid. Duplicate samples were evaluated by use of the intraclass correlation coefficient to determine reproducibility. To assess the magnitude of differences between replicate samples, the absolute mean difference, SD, and minimum and maximum values were calculated for each analyte. Median values and reference intervals were calculated. RESULTS: Intraclass correlation coefficient values were excellent for all analytes except alanine aminotransferase (good), Na (poor), gamma-glutamyltransferase (poor), and P (poor). Reference intervals were established. CONCLUSIONS AND CLINICAL RELEVANCE: The in-house tabletop biochemical analyzer had good precision for measuring most plasma biochemical analytes. Further research and comparison with other reference procedures are needed before reference intervals and precision can be established for globulin, Na, P, K, and albumin. Aquatic veterinarians may be able to use the reference intervals for adult koi as an important diagnostic tool or as part of a fish wellness program, as commonly done in other domestic species.     

Effect of age on reference intervals of serum biochemical values in kittens

OBJECTIVE: To determine the effect of age on reference intervals of serum biochemical values in kittens. DESIGN: Prospective clinical trial. ANIMALS: 55 kittens from 12 specific-pathogen-free queens. PROCEDURE: Kittens were allocated at birth into colostrum-fed (n = 27) and colostrum-deprived (28) groups. Blood was collected at birth and on days 1, 2, 4, 7, 14, 28, and 56. Serum samples were analyzed for activities of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, creatine kinase, lactate dehydrogenase, gamma-glutamyltransferase, amylase, and lipase and for concentrations of albumin, total protein, bilirubin, urea nitrogen, creatinine, cholesterol, glucose, calcium, phosphorus, and triglycerides by use of an automated analyzer. Total serum solids concentrations were determined by use of refractometry. Serum IgG concentrations were quantified by use of radial immunodiffusion. RESULTS: For several analytes, reference intervals changed rapidly, most notably during the first few days of life. Reference intervals for alkaline phosphatase, creatine kinase, lactate dehydrogenase, and triglycerides were higher from birth to 8 weeks than adult reference intervals. Aspartate aminotransferase, bilirubin, urea nitrogen, and creatinine were higher than in adults at birth but were similar to or lower than adult reference intervals by 8 weeks. Compared with adult reference intervals, reference intervals for calcium and phosphorus concentrations were higher and for albumin and total protein concentrations were lower throughout the study period. CONCLUSIONS AND CLINICAL RELEVANCE: Important differences exist between reference intervals for serum biochemical values of neonatal and adult cats. Age-appropriate reference intervals should be used for accurate assessment of serum biochemical test results in cats.     

Serum biochemical reference intervals for wild dwarf ornate wobbegong sharks (Orectolobus ornatus)

Background: Sharks are important to sport and commercial fishing, public aquaria, and research institutions. However, serum biochemical reference values have been established for few species. Objective: The aim of this study was to establish serum biochemical reference intervals for wild‐caught dwarf ornate wobbegong sharks (Orectolobus ornatus). Methods: Fifty wobbegongs were caught, and their health status, sex, length, and weight were evaluated and recorded. Following collection of blood, serum biochemical analytes were measured and analyzed using standard analytical and statistical methods. Combined samples generated means, medians, and reference intervals. Results: For the measured analytes, means (reference intervals) were as follows: sodium 287 (284–289) mmol/L, chloride 277 (274–280) mmol/L, potassium 5.2 (5.0–5.3) mmol/L, total calcium 4.6 (4.5–4.7) mmol/L, magnesium 1.9 (1.7–2.0) mmol/L, inorganic phosphate 1.8 (1.7–1.9) mmol/L, glucose 2.6 (2.4–2.8) mmol/L, total protein 46 (45–47) g/L, urea 396 (392–401) mmol/L, creatinine ≤0.02 mmol/L, total bilirubin 2.0 (1.9–2.1) μmol/L, cholesterol 1.3 (1.2–1.4) mmol/L, triglyceride 0.5 (0.4–0.6) mmol/L, alkaline phosphatase 24 (21–28) U/L, alanine aminotransferase 3 U/L, aspartate aminotransferase 28 (25–31) U/L, creatine kinase 49 (38–59) U/L, and osmolarity 1104 (1094–1114) mmol/L. Serum values were not affected by sex, length, or weight. Conclusions: Established reference values will assist with clinical evaluation and treatment of dwarf ornate wobbegongs in aquaria, research institutions, and the wild.     

Hematologic and biochemical reference intervals for Norwegian crossbreed grower pigs

Background: Hematologic and biochemical reference intervals depend on many factors, including environment and age. Reference intervals for Norwegian grower pigs are lacking, and previously published reference intervals for similar pigs from other countries are now outdated due to significant changes in management and breeding on the pig farms. Objectives: The aim of this study was to determine updated reference intervals for hematologic and biochemical analytes in healthy crossbred grower pigs, and to compare the results among 3 different farms. Methods: Blood samples were collected from 104 clinically healthy pigs of the most common Norwegian crossbreed (Landrace Yorkshire sow × Landrace Duroc boar). The pigs were 12–16 weeks old, weighed 30–50 kg, of both sexes, and lived on 3 farms in eastern Norway. Automated hematologic and biochemical analysis were performed using ADVIA 2120 and ADVIA 1650 analyzers. Results: Five samples were excluded because of hemolysis (1) or outliers (4). Reference intervals were calculated using parametric or nonparametric methods, depending on data distribution. Mean, median, minimum, and maximum values were tabulated. Conclusions: The reference intervals calculated in this study will be useful for the diagnosis and monitoring of disease in this widespread crossbreed pig. Compared with previously published reference values, reference intervals for total WBC count, creatine kinase and alanine aminotransferase activities, and albumin, bilirubin, and urea concentrations in this study differed notably.     

Optimizing the size of the area surveyed for monitoring a Eurasian lynx (Lynx lynx) population in the Swiss Alps by means of photographic capture–recapture

We studied the influence of surveyed area size on density estimates by means of camera‐trapping in a low‐density felid population (1–2 individuals/100 km²). We applied non‐spatial capture–recapture (CR) and spatial CR (SCR) models for Eurasian lynx during winter 2005/2006 in the northwestern Swiss Alps by sampling an area divided into 5 nested plots ranging from 65 to 760 km². CR model density estimates (95% CI) for models M₀ and M_h decreased from 2.61 (1.55–3.68) and 3.6 (1.62–5.57) independent lynx/100 km², respectively, in the smallest to 1.20 (1.04–1.35) and 1.26 (0.89–1.63) independent lynx/100 km², respectively, in the largest area surveyed. SCR model density estimates also decreased with increasing sampling area but not significantly. High individual range overlaps in relatively small areas (the edge effect) is the most plausible reason for this positive bias in the CR models. Our results confirm that SCR models are much more robust to changes in trap array size than CR models, thus avoiding overestimation of density in smaller areas. However, when a study is concerned with monitoring population changes, large spatial efforts (area surveyed ≥760 km²) are required to obtain reliable and precise density estimates with these population densities and recapture rates.