Membranoproliferative Glomerulonephritis in a Calf with Nephrotic Syndrome

Immune protection induced by E2 recombinant glycoprotein of bovine viral diarrhea virus in a murine model

Bovine viral diarrhea virus (BVDV) is considered the most important viral pathogen in ruminants worldwide due to the broad range of clinical manifestations displayed by infected animals. Therefore, infection with BVDV leads to severe economic losses in several countries' beef and dairy industries. Vaccination prevents reproductive failure and gastrointestinal and respiratory disorders caused by BVDV infection. However, considering their limitations, conventional vaccines such as live, attenuated, and killed viruses have been applied. Hence, different studies have described subunit vaccines as an effective and safe alternative for BVDV protection. Therefore, in this study, the ectodomain of E2 (E2e) glycoprotein from NADL BVDV strain was expressed in mammalian cells and used in two vaccine formulations to evaluate immunogenicity and protection against BVDV conferred in a murine model. Formulations consisted of solo E2e glycoprotein and E2e glycoprotein emulsified in adjuvant ISA 61 VG. Five groups of 6 mice of 6-to-8-week-old were immunized thrice on days 1, 15, and 30 by intraperitoneal injection with the mentioned formulations and controls. To evaluate the conferred protection against BVDV, mice were challenged six weeks after the third immunization. In addition, the humoral immune response was evaluated after vaccination and challenge. Mice groups inoculated with solo E2e and the E2e + ISA 61 VG displayed neutralizing titers; however, the E2 antibody titers in the E2e + ISA 61 VG group were significantly higher than the mice group immunized with the solo E2e glycoprotein. In addition, immunization using E2e + ISA 61 VG prevents animals from developing severe lesions in surveyed tissues. Moreover, this group acquired protection against the BVDV challenge, evidenced by a significant reduction of positive staining for BVDV antigen in the lungs, liver, and brain between the experimental groups. Our findings demonstrated that using E2e + ISA 61 VG induces greater BVDV protection by an early humoral response and reduced histopathological lesions and BVDV antigen detection in affected organs, indicating that E2e + ISA 61 VG subunit formulation can be considered as a putative vaccine candidate against BVDV. The efficacy and safety of this vaccine candidate in cattle requires further investigation.

Comparative physiological, morphological, histological, and AQP2 immunohistochemical analysis of the Arabian camels (Camelus dromedarius) and oxen kidney: Effects of adaptation to arid environments

Compared to other mammals, Arabian camels are ideal models for exploring the structural adaptations that enable camels to survive in arid environments. Thus, this study aimed to explore how evolutionary adaptation to arid conditions modifies the characteristics of the kidneys in Arabian camels (Camelus dromedarius) compared to oxen. Urine samples were physically and chemically analyzed. Harvested kidneys were subjected to topographical and fast spin echo magnetic resonance (FSE-MR) imaging. Histology, histomorphometry, and Aquaporin-2 (AQP2) expression by immunohistochemistry were also performed. Here, in dromedaries, sodium and potassium values in the urine were much higher (p=0.001, for both), whereas chloride was much lower (p=0.004) than the values of oxen. Compared with oxen, the level of the hormone aldosterone in serum was significantly lower (p=0.002), whereas creatinine and urea were significantly higher (p=0.005 and p=0.001, respectively). Uric acid in dromedaries and oxen did not differ significantly (p=0.349). Like sodium levels (p=0.001) in dromedary serum, chloride was also much higher (p=0.002) than in oxen. The average value of potassium was much lower (p=0.009) than that of oxen. Morphologically, anatomical and FSE MRI studies revealed that minor and major calyces were not found in dromedary kidneys. The renal pelvis was not found in oxen, and the major calyx was directly connected to the ureter. The dromedary kidney contained a wider medullary portion as well as increased diameters for renal corpuscles (RCs), proximal convoluted tubules (PCTs), and collecting tubules (CTs, p<0.05) compared with the oxen. We also noted that AQP2 was significantly expressed in dromedary nephron components, except for RCs, compared with oxen as shown by immunohistochemistry. Overall, these data strongly suggest that the dromedary has a greater ability to adapt to harsh desert conditions in terms of producing highly concentrated urine than oxen.

Urine protein-to-creatinine ratio in cattle with subclinical renal disease

BACKGROUND

Urinalysis is not routinely used in bovine medicine, and there is no evidence as to whether urine protein-to-creatinine ratio (UPC) could be used for the diagnosis of renal diseases in cattle.

OBJECTIVE

The goal of the study was to determine alterations in UPCs observed with different subclinical renal diseases in clinically healthy cattle and to investigate whether UPC can efficiently differentiate cattle with and without subclinical renal pathology.

METHODS

Kidney and urine samples from 57 clinically healthy adult dairy (44) and beef (13) cattle were collected after slaughter. Urinary protein and creatinine concentrations were measured in an automatic analyzer, and urinary-specific gravity (USG) was measured using a temperature compensated refractometer. Kidney samples underwent histopathologic examination, and the cattle were classified as NL (no renal lesion) and L (lesions detected even in one kidney). Based on USG, the cattle were divided into the Normal USG (≥1.020) and Low USG (<1.020) groups. The cattle with either histopathologic lesions or low specific gravities were considered to have renal disease.

RESULTS

Renal lesions were detected in 37 cattle. UPC values were significantly affected (P < .05) by USG values, and not by the type of lesion detected, breed, or age, and their interactions (P > .05). The analysis revealed that a UPC of ≥0.19 provided an optimal cut-off point for the differentiation between normal animals and those with renal disease with 66.0% sensitivity and 90% specificity.

CONCLUSIONS

The UPC calculation is a useful tool for the differentiation of normal cattle and those with renal disease. A UPC of less than 0.19 is associated with the absence of renal damage, whereas higher values raise suspicion for renal disease.

Urinalysis and determination of the urine protein-to-creatinine ratio reference interval in healthy cows

Background

There are no reference intervals for urinalysis in cattle.

Hypothesis/Objectives

Characterize the urine of healthy cows, establish urine protein‐to‐creatinine ratio (UPC) reference intervals, and test possible differences among dairy and beef cattle, age groups, or stage of lactation.

Animals

Seventy‐seven dairy and 74 beef 2.5 to 17 year‐old cows of different breeds housed mainly in free stall.

Methods

In this prospective study, urine specimens were collected by catheterization. Complete urinalysis was performed within 1 hour including specific gravity, dipstick evaluation, visual urine pH evaluation with 0.3 pH unit graded strips, and microscopic evaluation of the sediment. Urinary protein and creatinine concentrations and protein electrophoresis were determined on frozen aliquots.

Results

Overall reference intervals were 1.020 to 1.045 for USG, 7.0 to 8.7 for pH, and 0.04 to 0.25 for UPC; because of differences in creatinine concentration, UPC was lower in beef (0.04‐0.14) than in dairy (0.05‐0.25) cows and in the latter in dry than lactating cows. With dipstick evaluation, most analytes were absent except for blood, ketone, and protein in 24.7, 16.0, and 64.7% of cases, respectively. Microscopic evaluation revealed less than 3 red blood cells, leukocytes, and epithelial cells in 84, 99.3, and 100% cows, respectively. No band was observed at electrophoresis, except in 1 case at MW ~66 000.

Conclusions and Clinical Importance

Creatininuria is higher in beef than dairy cows and proteinuria is likely more efficiently characterized by protein concentration than by UPC.

Immune complex glomerulonephritis of suspected iatrogenic origin in five Japanese Black calves

Five Japanese Black embryo transfer calves from a single embryo flush, 30 to 45-days-old, including 4 live animals for clinical examination and 1 dead for necropsy, were presented with a history of decreased milk intake and hypoproteinemia. Consistent clinicopathological abnormalities in the 4 calves presented for clinical evaluation included hyperkalemia, hyperphosphatemia, hypoproteinemia, hypoalbuminemia, hyperbilirubinemia, increased creatine phosphokinase activity, and proteinuria. Four calves ultimately were necropsied and all had histologic evidence of immune complex glomerulonephritis. Glomerulonephritis in these calves was hypothesized to have resulted from the interaction of passively acquired antibodies at birth and active immunization at 7 and 28 days of age with a Salmonella Typhimurium core antigen vaccine.