Dogs with chronic kidney disease (CKD) may have alterations in the glomerular filtration barrier, including podocyte loss. Detection of podocyte mRNA in urine could be useful for assessing podocyturia in dogs with kidney disease. The objective of this study was to evaluate the presence of nephrin mRNA (NPHS1) and podocin mRNA (NPHS2) in urine sediments of dogs with naturally occurring CKD and healthy dogs. Twenty-four dogs, 14 with CKD and 10 as healthy controls, underwent clinical evaluation. The dogs with CKD were divided into two groups, according to the International Renal Interest Society criteria: stage 1 or 2 CKD (n = 5) and stage 3 or 4 CKD (n = 9). Urine was collected by catheterisation or free catch and RNA isolation from the urine sediments was optimised using glycogen as a co-precipitant. Detection of NPHS1 and NPHS2 in the sediment samples was performed using quantitative real-time PCR. Both types of mRNA were detected in samples from all groups, but the percentages of detection were higher in the group of dogs with stage 1 or 2 CKD and lower in the group of dogs with stage 3 or 4 disease. Physiological podocyturia was observed in healthy dogs, and the results suggest differential podocyturia in dogs with CKD, according to the stage of the disease, i.e. an increase in podocyturia in dogs at stage 1 or 2 and a reduction in podocyturia in dogs at stage 3 or 4.

Porcine circovirus 4 (PCV4) was first discovered in 2019 in a herd of pigs with porcine respiratory disease, dermatitis and nephropathy syndrome in Hunan Province, China. It has subsequently been detected in other provinces and in South Korea. In consideration of the potential of the virus to cause an epidemic, rapid, sensitive, and specific detection of PCV4 is needed, as is the facilitation of further epidemiological research through elucidation of the whole genome of PCV4. This study had those two aims. Fifty-five blood samples, two pig tissue samples, nine saliva swabs and one semen sample which all originated from Sichuan province pig farms were analysed. The virus’ genome of 1,770 bp was synthesised artificially based on a Chinese reference strain and primers and probes for the ORF2 gene were designed. Then, the amplified target fragment was cloned into the pMD19-T vector and a series of diluted recombinant plasmids were used to generate a standard curve. An optimised real-time TaqMan PCR method was established. The results of this study showed that the established method is specific for PCV4 but not for other viruses, and has amplification efficiency of 99.6%, a regression squared value (R²) of 1.000 and a detection limit of 2.2×10 DNA copies. This method was shown to be analytically specific and sensitive with a low intra- and inter-assay coefficient of variation (<1.67 %). Of a total of 67 clinical samples tested using the established method, three were shown to be positive (4%). This study confirms the existence of PCV4 in Sichuan and provides a promising alternative tool for rapid detection of PCV4.

Swine DNA viruses have developed unique mechanisms for evasion of the host immune system, infection and DNA replication, and finally, construction and release of new viral particles. This article reviews four classes of DNA viruses affecting swine: porcine circoviruses, African swine fever virus, porcine parvoviruses, and pseudorabies virus. Porcine circoviruses belonging to the Circoviridae family are small single-stranded DNA viruses causing different diseases in swine including poly-weaning multisystemic wasting syndrome, porcine dermatitis and nephropathy syndrome, and porcine respiratory disease complex. African swine fever virus, the only member of the Asfivirus genus in the Asfarviridae family, is a large double-stranded DNA virus and for its propensity to cause high mortality, it is currently considered the most dangerous virus in the pig industry. Porcine parvoviruses are small single-stranded DNA viruses belonging to the Parvoviridae family that cause reproductive failure in pregnant gilts. Pseudorabies virus, or suid herpesvirus 1, is a large double-stranded DNA virus belonging to the Herpesviridae family and Alphaherpesvirinae subfamily. Recent findings including general as well as genetic classification, virus structure, clinical syndromes and the host immune system responses and vaccine protection are described for all four swine DNA virus classes.

Objective: To compare the use of a single-sample method involving IV administration of iodixanol with a multisample method involving inulin for the estimation of glomerular filtration rate (GFR) in cats. Animals: 24 cats, including 15 healthy cats and 9 cats with naturally occurring renal diseases. Procedures: Each cat was coadministered iodixanol (a nonionic contrast medium; dose providing 40 mg of I/kg) and inulin (50 mg/kg), IV, and blood samples were collected 60, 90, and 120 minutes later. Serum iodixanol and inulin concentrations were determined by means of high-performance liquid chromatography and colorimetry, respectively. Serum urea nitrogen and creatinine concentrations were also measured. Results: Analysis of the data from healthy cats and cats with naturally occurring renal diseases revealed an excellent correlation between GFR values estimated by the multisample and single-sample methods with iodixanol. Likewise, GFR values estimated from the single-sample method with iodixanol were closely correlated with those calculated from the multisample method with inulin. Conclusions and Clinical Relevance: For estimation of GFR in cats, use of a single-sample method with iodixanol, instead of a multisample procedure, may be an expedient tool in both clinical and research settings because of its benefits to patient well-being as a result of reduced stress associated with blood sample collection.

Objective: To estimate the prevalence of perinuclear antineutrophilic cytoplasmic autoantibodies (pANCA) in the serum of healthy Soft Coated Wheaten Terriers (SCWTs) in the United Kingdom and to identify potential risk factors and heritability patterns associated with a positive result for pANCA. Animals: 188 SCWTs (age range, 18 months to 14.3 years). Procedures: Blood samples were obtained from SCWTs in various locations in England. Serum was tested for pANCA by use of an immunofluorescence assay, and total protein and albumin concentrations were determined. Pedigrees were evaluated to identify close relatives that had protein-losing enteropathy (PLE) or protein-losing nephropathy (PLN). Results: 39 of 188 (20.7%) dogs, including young dogs, had positive results for pANCA. Dogs had significantly higher odds of having positive results for pANCA if they had at least 1 littermate that had PLE or PLN (odds ratio, 12.1) or if they had at least 1 full sibling from another litter known to be affected with PLE or PLN (odds ratio, 4.0). Conclusions and Clinical Relevance: This study revealed a high prevalence of pANCA in the serum of a representative sample of healthy SCWTs in the United Kingdom and a significant association between positive results for pANCA and a diagnosis of PLE or PLN in a sibling.

Gentamicin sulfate-induced nephrotoxicosis was compared in 2 groups of horses fed different rations. Four horses were fed only alfalfa hay, and 4 other horses were fed only whole oats. Seven days after initiation of the diet, all horses were given gentamicin IV (5 mg/kg of body weight) every 12 hours for 22 days. Urinary gamma-glutamyltransferase to urinary creatinine (UGGT:UCr) ratio was calculated daily, and serum concentration of gentamicin was measured at 1 and 12 hours after drug administration. Results indicated that horses fed oats had greater renal tubular damage than did horses fed alfalfa. Mean UGGT:UCr for horses fed alfalfa was 47.1 +/- 18.8 and was 100.0 +/- 19.0 for horses fed oats (P = 0.007). The UGGT:UCr in horses fed oats was > 100 for a total of 54 days; horses fed alfalfa had UGGT:UCr > 100 for only 7 days. Two horses not given gentamicin were fed only oats and 2 were fed only alfalfa. These horses had mean UGGT:UCr of 17.6 +/- 2.2 and 30.5 +/- 3.0, respectively. Mean peak and trough concentrations of gentamicin were statistically different for horses fed oats and those fed alfalfa (peak 23.16 +/- 1.87 and 14.07 +/- 1.79 microgram/ml, respectively [P = 0.0001], and trough, 1.81 +/- 0.69 and 0.71 +/- 0.70 microgram/ml, respectively [P = 0.02701)]. Mean half-lives of gentamicin (estimated from peak and trough concentrations) for horses fed alfalfa (2.58 +/- 0.26 hours) and horses fed oats (2.88 +/- 0.27 hours) were not significantly different. Horses fed only oats had greater degree of gentamicin-induced nephrotoxicosis than did those fed only alfalfa.

Ultrasonographic or anatomic observations or both were made of the kidneys of 26 dogs. The anatomic studies established precise correlations between the gross anatomic features of the organ and its ultrasonographic images obtained in transverse, sagittal, dorsal, and 2 oblique planes. Uniformily mottled echogenicity of the renal cortex could be clearly differentiated from the less echogenic renal medulla. In the middorsal plane, the papillae of the renal pyramids were directed towards the renal sinus. The bases of the pyramids were almost circular in outline in the midsagittal images and the renal crest was seen as an echogenic line. Although the renal sinus was highly echogenic, neither the renal pelvis nor its recesses were detected. The walls of each of the interlobar arteries provided echogenic parallel lines, passing in the renal recesses between the renal pyramids. Arcuate arteries were demonstrated at the corticomedullary junction and interlobular arteries were detected within the renal cortex. For the right kidney, transverse images were obtained with the ultrasonographic transducer at the last 2 intercostal spaces; images in the dorsal, sagittal, and oblique planes were obtained with the transducer placed over the caudal extremity of the kidney. In the left kidney, transverse images were made with the transducers at, and caudal to, the last intercostal space; images in the dorsal, sagittal, and oblique planes were obtained with the transducer placed over the lateral border of the kidney. The use of such a protocol ensures that the entire organ is inspected and a diagnosis of either a normal or pathologic kidney is made.

Serum from dogs with surgically induced renal impairment was incorporated into the medium for erythroid bone marrow cultures. A significant correlation was found between serum activities of erythropoietin and numbers of erythroid colony-forming units grown in culture. Serum creatinine concentrations had no correlation, and serum parathyroid hormone activities had a negative correlation with numbers of erythroid colony-forming units that was below the level of significance. Purified 1-84 parathyroid hormone added to bone marrow cultures was found to be stimulatory to erythroid colony-forming unit growth in higher concentrations, but decreased the number of burst-forming units. Unmeasured substances in the canine serum appeared to have a greater effect on the canine erythroid bone marrow cultures than did creatinine or parathyroid hormone values.

Urinary liver-type fatty acid-binding protein (uL-FABP) is a clinically useful biomarker for monitoring chronic kidney disease (CKD) in humans. However, long-term monitoring of uL-FABP in CKD cats has not been reported. The objective of this preliminary study was to investigate whether the urinary excretion of L-FABP could predict the deterioration of renal function in 2 CKD model cats. Urinary liver-type fatty acid-binding protein (uL-FABP) increased before standard renal biomarkers, including serum creatinine, blood urea nitrogen, and symmetric dimethylarginine, in 1 cat with deteriorating renal function, but remained low and relatively stable in another cat with stable renal function. Our results suggest that uL-FABP is a potential clinical biomarker for predicting the progression of CKD in cats, as it is in humans.

OBJECTIVE To establish a reference interval for glomerular filtration rate (GFR) determined by measuring serum clearance of a single IV dose of inulin in clinically normal cheetahs (Acinonyx jubatus) and compare serum symmetric dimethylarginine (SDMA) concentration in cheetahs with GFR. ANIMALS 33 cheetahs housed at 3 institutions. PROCEDURES A single bolus of inulin (3,000 mg/m2) was administered IV, and 5 serial blood samples were collected and analyzed for serum inulin concentration with the anthrone technique. The GFR was estimated with a modified slope-intercept method for the slow component of the serum concentration-versus-time curve. Blood urea nitrogen and serum creatinine concentrations were measured in samples obtained immediately prior to inulin administration, and serum SDMA concentration was measured in stored samples. RESULTS Mean ± SD measured GFR was 1.58 ± 0.39 mL/min/kg, and the calculated reference interval was 0.84 to 2.37 mL/min/kg. There were significant negative correlations between GFR and serum creatinine concentration (r = −0.499), BUN concentration (r = −0.592), and age (r = −0.463). Serum SDMA concentration was not significantly correlated with GFR (r = 0.385), BUN concentration (r = −0.281), or serum creatinine concentration (r = 0.165). CONCLUSIONS AND CLINICAL RELEVANCE A reference interval for GFR in clinically normal cheetahs was obtained. Further evaluation of animals with renal disease is needed to determine whether measuring serum clearance of a single IV dose of inulin is a reliable diagnostic test for early detection of renal disease in cheetahs.