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Setaria marshalli is a mosquito-borne filarial nematode that causes infection in calves younger than two years old. In the present study, nematodes were obtained from a calf in Japan and morphologically identified as S. marshalli. Additionally, the partial cytochrome oxidase subunit I (COI) region (596 bp) was analyzed for the first time to establish a reliable DNA barcode. Nucleotide sequences of COI were identical among the seven worms obtained. The COI region can be a useful marker for species discrimination in the case of S. marshalli since nucleotide variations observed between the closest congener, Setaria cervi (51/596 bp), were sufficient to allow species discrimination. However, the phylogenetic relationship of S. marshalli with its congeners was unclear in a maximum likelihood tree. We found that the partial COI sequence of S. marshalli analyzed in the present study matched a relevant section of the complete mitochondrial genome of S. labiatopapillosa that was deposited in the International Nucleotide Sequence Database. This finding suggests that S. marshalli was misdiagnosed as S. labiatopapillosa in a previous study. It is crucial to conduct accurate morphological analyses to obtain reliable molecular information regarding Setaria nematodes.Première caractérisation génétique de Setaria marshalli (Nematoda, Spirurida) avec un code-barres ADN fiable basé sur un marqueur génétique mitochondrial.Setaria marshalli est une filaire transmise par les moustiques qui provoque une infection chez les veaux de moins de deux ans. Dans la présente étude, les nématodes ont été obtenus à partir d’un veau au Japon et identifiés morphologiquement comme S. marshalli. De plus, la région partielle de la sous-unité I (COI) de la cytochrome oxydase (596 pb) a été analysée pour la première fois afin d’établir un code-barres ADN fiable. Les séquences nucléotidiques de COI étaient identiques parmi les sept vers obtenus. La région COI peut être un marqueur utile pour la discrimination des espèces dans le cas de S. marshalli puisque les variations de nucléotides observées avec le congénère le plus proche, Setaria cervi (51/596 pb) étaient suffisantes pour permettre la discrimination des espèces. Cependant, la relation phylogénétique de S. marshalli avec ses congénères n’était pas claire dans un arbre à maximum de vraisemblance. Nous avons constaté que la séquence COI partielle de S. marshalli analysée dans la présente étude correspondait à une section pertinente du génome mitochondrial complet de S. labiatopapillosa qui a été déposée dans la base de données internationale de séquences de nucléotides. Cette découverte suggère que S. marshalli a été diagnostiqué à tort comme S. labiatopapillosa dans une étude précédente. Il est crucial de mener des analyses morphologiques précises pour obtenir des informations moléculaires fiables concernant les nématodes du genre Setaria.

Calving difficulty may lead to traumatic peripheral nerve injury. A male, 8-mo-old, Japanese Black calf with a history of secondary dystocia as a result of fetal gigantism had lameness and gait disturbance. At autopsy, multifocal dural thickening with adhesions to the adjacent spinal cord was observed at T12–13 and L4–5 vertebral levels. Microscopically, numerous traumatic neuroma-like fascicles of nerve twigs were embedded in the dura mater with abundant collagenous connective tissue. By immunohistochemistry, axons and Schwann cells were confirmed in each nerve fascicle. Our observations suggest that avulsion injuries in the preganglionic fibers of the spinal nerve roots, and secondary spinal cord compression, resulted in the development of neurologic signs.

This study was to examine the effects of dietary vitamin K (VK) 3 supplementation on immune-related substances in milk, oxidative stress indices in plasma and VK1, and menaquinone 4 (MK-4) in plasma and milk in periparturient dairy cows. Forty healthy perinatal Holstein-Friesian dairy cows were used in this study. Twenty-one animals were randomly selected and categorized into the VK3 supplemented (50 mg/day/head as VK3) group; the remaining 19 were categorized into the control group. On day 3 after calving, blood and milk were sampled, and their chemical components were determined. The VK3 supplemented group had significantly higher menaquinone 4 levels in plasma and milk on day 3 postpartum than the control group. In addition, there was a significant increase in the immunoglobulin G (IgG) level in milk. VK3 may be absorbed from the gastrointestinal tract and converted to MK-4, the biologically active form of VK, in the mammary gland and other tissues. It was thought that the increase in MK-4 level in plasma and milk induced an increase in the concentration of IgG in milk. VK3 supplementation to periparturient dairy cows may contribute to the production of colostrum with high concentrations of IgG and MK-4.

Introduction Dairy cows may infrequently give milk tinged with blood after calving, which is a condition termed haemolactia. Economic losses for dairy farmers are caused by cases of haemolactia because of the condemnation of such milk, potential contamination of good bulk tank milk with haemolactic milk, and need for veterinarian intervention. This study was performed to elucidate the oxidative status of dairy cows with haemolactia during the peripartum period. Material and Methods Plasma glutathione peroxidase, malondialdehyde (MDA) and superoxide dismutase concentrations along with serum vitamin A, C and E concentrations were determined as indices of oxidative stress. The sampled dairy cows comprised two haemolactic (n = 11 and n = 6) and two non-haemolactic (n = 11 and n = 6) groups. Results On the first day when haemolactia was identified in colostrum (at mean 2.1 days after parturition), a significantly increased concentration of plasma MDA was noted in the haemolactic group. During the prepartum period, low levels of serum vitamin E were continuously observed from prepartum week 4 to the parturition day but only in the haemolactic group. Conclusion These results demonstrate that continuous low levels of serum vitamin E in the prepartum period may play a pivotal role as a requisite factor in the onset of haemolactia after calving.

Bovine foamy virus (BFV) is distributed through worldwide cattle herds. Although the biological features of BFV are not well understood, appearance of clinical manifestation by superinfection with other microorganisms is inferred. In Japan, reports of genomic characterizations and epidemiology of this virus are limited. In this study, we performed whole genomic sequencing of BFV strains Ibaraki and No.43, which were isolated in this country. Additionally, we investigated BFV in geographically distant four daily farms in Japan, to estimate the distribution of BFV and its correlation to bovine leukemia virus (BLV). BFV was distributed throughout Japan; the average positive rate was 12.7%. The nucleotide sequence identities of the isolates were 99.6% when compared with BFV strain isolated in the USA. The phylogenetic tree using env gene sequence showed strains Ibaraki, No.43 and Kagoshima were sorted in the same cluster including the USA and Chinese strains, while Hokkaido strain was in the other cluster including European strains. Although no clear correlation between BFV and BLV could be found, BFV and BLV infections were likely to increase with ages. Our data on epidemiology and characteristics of BFV will provide important information to reveal biological features of BFV.

We investigated the effects of active dried Saccharomyces cerevisiae (ADSC) on ruminal pH, fermentation, and the fluid bacterial community during the short-term ruminal acidosis challenge. Five rumen-fistulated male Holstein calves (147.0 ± 5.8 kg of body weight; 3.6 ± 0.2 mo of age) were used in a crossover design, and 0 g (control group, n = 5) or 2 g (SC group, n = 5) of ADSC (1 × 1010 cfu/g) was administered twice daily for 21 consecutive days. Calves were fed a high-forage diet during the first 15 d (d -14 to d 0; prechallenge), a high-grain diet for 2 d (d 1 and 2; ruminal acidosis challenge), and a high-forage diet for 4 d (d 3 to 6; postchallenge). Ruminal pH was measured continuously. Rumen fluid samples were collected once daily (0800 h) on d 0, 3, 4, and 6 and twice daily (0800 and 1100 h) on d 1 and 2. Bacterial DNA was extracted from fluid samples collected on d 0 and 3. The 24-h and 1-h mean ruminal pH was significantly depressed during the ruminal acidosis challenge in each group, although the changes were more severe in the SC group, consistent with a significant increase in lactic acid on d 2 (1100 h) compared with d 0 and a significantly higher proportion of butyric acid on d 2 (1100 h) compared with the control group. Feeding a high-grain diet caused a decrease in bacterial diversity due to high acidity in both groups. The relative abundances of the genus Bifidobacterium and operational taxonomic unit (OTU) 3 (Bifidobacterium species) increased significantly in both groups but were higher in the SC group. Correlation analyses indicated that OTU3 (Bifidobacterium species) were positively correlated with lactic acid concentration and that OTU1 (Prevotella species) and OTU5 (Succinivibrio species) were correlated with the proportion of butyric acid. These results suggest that ADSC supplementation induced the intense decreases in ruminal pH by increased butyric and lactic acid production through a high-grain diet fermentation by rumen fluid bacterial species during the short-term ruminal acidosis challenge in Holstein calves after weaning.

We investigated changes in the predicted functions of the rumen bacterial community in Japanese Black beef cattle during fattening. Nine cattle were fed a high-concentrate diet during the early, middle, and late fattening stages consecutively (10-14, 15-22, and 23-30 months of age, respectively). The rumen fluid and solid samples collected at each stage were subjected to sequencing analyses. The sequencing results were clustered and classified into operational taxonomic units (OTUs). Representative sequences and a raw counting table for each OTU were submitted to the Piphillin website. The predicted functions were revealed by the Kyoto Encyclopedia of Genes and Genomes database as the ratio of the total sequence. In the early stage, "Biosynthesis of secondary metabolites" was significantly higher in the fluid fraction than in the solid fraction. "Two-component system" in the middle stage was significantly lower and "Purine metabolism" in the late stage was significantly higher in the fluid fraction than those in the solid fraction. The fluid fraction was significantly correlated with acetic acid, propionic acid, and bacterial metabolism, such as "Biosynthesis of secondary metabolites" and "Sugar metabolism." Moreover, the solid fraction was correlated with "Purine metabolism" and "Biosynthesis of secondary metabolism". These results suggest that the rumen bacterial community in Japanese Black beef cattle adapts to changes in rumen conditions by altering their functions in response to a long-term high-grain diet.

Bovine leukemia virus (BLV) is an oncogenic virus belonging to the genus Deltaretrovirus and is the causative agent of enzootic bovine leukosis. Proviral load (PVL) determined by real-time quantitative PCR (qPCR) is now widely used as an indicator of not only BLV infection, but also BLV disease progression. To interpret PVLs determined by different qPCRs used in Japan, we compared a chimeric cycling probe-based qPCR, CY415, targeting the BLV tax region; a TaqMan probe-based qPCR, RC202, targeting the BLV pol region; and a TaqMan probe-based qPCR, CoCoMo, targeting the BLV long terminal repeat (LTR) region. Whole-blood samples collected from 317 naturally BLV-infected cattle (165 Holstein–Friesian and 152 Japanese Black) and tumor tissue samples collected from 32 cattle at a meat inspection center were used. The PVLs determined by each qPCR were strongly correlated. However, the PVL and the proportion of BLV-infected cells determined by RC202 or CoCoMo were significantly higher than those determined by CY415. Genetic analysis of three tumor tissue samples revealed that LTR region mutations or a deletion affected the PVL determined by CoCoMo. These results suggest that the TaqMan-based RC202 or CoCoMo qPCR is better than CY415 for BLV PVL analysis. However, qPCR target region mutations were not rare in tumors and could hamper PVL analysis by using qPCR.

Bovine leukemia virus (BLV) proviral load is controlled by T-cell responses, which require vitamin A (VA) derived from food. However, whether dietary VA restriction for marbling impairs the T-cell responses that control BLV proviral load in beef cattle is unknown. We assessed T-cell subsets, interferon (IFN)-γ gene expression, and BLV proviral load in naturally BLV-infected Japanese Black cattle that were fed a diet with decreased VA levels. We found that the percentage of CD4+ T cells increased over time during dietary VA restriction. In addition, BLV proviral load was negatively correlated with the percentage of CD4+ T cells and with the level of IFN-γ gene expression. These observations suggest that dietary VA restriction for marbling enhances T-cell responses that control BLV proviral load and thus does not promote leukemogenesis in fattening beef cattle.

We investigated changes in oxidative stress markers during the transition period in healthy Holstein cows and those with postpartum diseases. Transition control (TC) Holstein cows (n=9) were evaluated for longitudinal changes during the transition period and postpartum diseased (PD) cows with ketosis (n=10), abomasal displacement (n=9), and acute mastitis (n=10) were evaluated in comparison to control cows (n=10). In the TC group, blood samples were collected at 2 weeks prepartum and at 1, 2, 4, 6, and 8 weeks postpartum. Milk yield and composition were measured at 2 and 4 weeks postpartum. In the PD group, blood samples were collected at the first day of examination during the 60 days postpartum. Peripheral oxidative stress parameters (malondialdehyde, MDA; potential antioxidant capacity, PAO; and glutathione peroxidase) were measured, and biochemical analyses were performed. In the TC group, MDA increased significantly postpartum and was correlated with milk yield, blood glucose (Glu), free fatty acid (FFA), β-hydroxybutyric acid (BHB), and aspartate aminotransferase. Compared to the control cows, PD cows with ketosis had significantly higher MDA and significantly lower PAO. Moreover, MDA was significantly correlated with Glu, FFA, and BHB. Postpartum increase in MDA might interact with milk yield and Glu, FFA, and BHB in the TC cows, and postpartum diseases, especially ketosis, might signify its increase and interaction with Glu, FFA, and BHB.

This study was conducted on red foxes to determine the appropriate voltage in electroejaculation for semen collection from stud males, and to confirm whether frozen semen with bovine semen extender can be used for artificial insemination. The proper load voltage for electroejaculation was 3-4 V based on semen collection rates and concentrations of spermatozoa. Frozen semen was prepared according to the known procedure for cows. In frozen-thawed semen, a relatively high conception rate (81.3%) was obtained in vixens, in which the optimum insemination time was detected by vaginal electrical resistance. These findings demonstrate that the restricted condition for semen collection by electroejaculation with cryopreservation of semen using bovine semen extender can be applied to artificial insemination of red foxes.

Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis (EBL), a malignant B cell lymphoma. However, the mechanisms of BLV-associated lymphomagenesis remain poorly understood. Here, after deep sequencing, we performed comparative analyses of B cell microRNAs (miRNAs) in cattle infected with BLV and those without BLV. In BLV-infected cattle, BLV-derived miRNAs (blv-miRNAs) accounted for 38% of all miRNAs in B cells. Four of these blv-miRNAs (blv-miR-B1-5p, blv-miR-B2-5p, blv-miR-B4-3p, and blv-miR-B5-5p) had highly significant positive correlations with BLV proviral load (PVL). The read counts of 90 host-derived miRNAs (bta-miRNAs) were significantly down-regulated in BLV-infected cattle compared to those in uninfected cattle. Only bta-miR-375 had a positive correlation with PVL in BLV-infected cattle and was highly expressed in the B cell lymphoma tissue of EBL cattle. There were a few bta-miRNAs that correlated with BLV tax/rex gene expression; however, BLV AS1 expression had a significant negative correlation with many of the down-regulated bta-miRNAs that are important for tumor development and/or tumor suppression. These results suggest that BLV promotes lymphomagenesis via AS1 and blv-miRNAs, rather than tax/rex, by down-regulating the expression of bta-miRNAs that have a tumor-suppressing function, and this downregulation is linked to increased PVL.

The effectiveness of on-farm continuous flow high-temperature short-time (HTST) pasteurization (i.e., 72°C for 15 s) for the inactivation of bovine leukemia virus (BLV) in milk was investigated with a sheep bioassay. Four sheep that had been inoculated with completely pasteurized milk containing approximately 3.4 × 107 BLV-infected peripheral blood mononuclear cells (PBMC) and treated by either HTST pasteurization or laboratory-scale low-temperature long-time (LTLT) pasteurization (i.e., 60°C for 30 min), remained negative for BLV for at least 17 weeks after inoculation. In contrast, all sheep inoculated with unpasteurized or inadequately pasteurized milk containing the same number of BLV-infected PBMC were tested positive for BLV and anti-BLV antibodies within 3 weeks after inoculation. These results suggest that on-farm continuous flow HTST pasteurization was equivalent value with inactivated BLV on the LTLT procedure and can effectively inactivate BLV in the milk. Therefore, on-farm HTST pasteurization of the pooled colostrum or milk used in automated feeding systems is likely to protect group-housed preweaned calves from BLV infection, thereby improving animal health on dairy farms.

The objective of the present study was to identify the effect of feeding management on disease incidence and blood metabolite levels in dairy herds in Iwate Prefecture, Japan. A generalized linear model approach was used to identify the risk factors for ketosis and displaced abomasum (DA) in dairy herds (n=30), and metabolic profile test (MPT) results were compared to verify the involvement of the factors. Consequently, the proportion of corn silage (CS) with ≥30% of dry matter (DM) fed to cows during the lactation period was confirmed as the most reliable risk factor for ketosis, while no risk factor was identified for DA. Meanwhile, the incidence rates of ketosis and DA were significantly (P

We investigated the relationship between ruminal pH and transcriptomic adaptation of the rumen epithelium (RE) of calves fed calf starter with and without forage during the weaning transition. Holstein calves were assigned to groups fed calf starter either with forage (HAY group, n = 3) or without forage (CON group, n = 4). Ruminal pH was measured continuously, and rumen fluid and epithelium were collected 3 wk after weaning. mRNA expression profiles of the RE were examined by one-color microarray. Differentially expressed genes (DEGs) were investigated using the Ingenuity Pathway Analysis (IPA). Mean and maximum ruminal pH were significantly ( P < 0.05) higher, and the duration of pH < 5.8 during 1 day was significantly ( P < 0.05) shorter, in the HAY group. The proportion of ruminal acetate and the acetate-to-propionate ratio were significantly ( P < 0.05) lower in the CON group. DEGs encoding transcription regulators (SREBP1), insulin-like growth factor binding proteins (IGFBP7 and CTGF), ketogenic enzymes (HMGCL, BDH1, and BDH2), and a transporter (SLC16A3) were identified ( P < 0.05) between the two groups. A growth factor (TGFB1) and signaling pathway (EGF and EGFR) were activated as upstream regulators. These results suggest that dietary forage alleviates ruminal acidosis, and the decrease in ruminal pH may damage the RE, leading to changes in gene expression to repair the damage. Furthermore, rumen development may be regulated by growth factor (TGFB1) and signaling pathways (EGF and IGFBP) for adaptation to feeding on calf starter with and without forage during the weaning transition.

Effects of a bacterial probiotic (BP) on ruminal fermentation and plasma metabolites were evaluated in four Holstein cattle (body weight, 645 ± 62 kg; mean ± SD) with induced subacute ruminal acidosis (SARA). SARA was induced by feeding a SARA-inducing diet, and thereafter, 20, 50 or 100 g per head of a commercial BP was administered for 7 consecutive days during the morning feeding. Cattle without BP served as the control. The 24-hr mean ruminal pH in the control was lower, whereas those in the BP groups administered 20 or 50 g were significantly higher compared to the control from days 2 to 7. Circadian patterns of the 1-hr mean ruminal pH were identical (6.4–6.8) among all cattle receiving BP. Although the mean minimum pH in the control on day –7 and day 0 was 5.8 and significantly higher than that of the control group ( >5.2). Ruminal volatile fatty acid (VFA) concentrations were not affected by BP treatment; however, the BP groups had lower lactic acid levels compared with the control group at 20:00 on day 7. Additionally, non-esterified fatty acid levels decreased from 8:00 to 20:00 in all BP groups on day 7. These results suggest that administration of 20 to 50 g of a multi-strain BP for 7 days might improve the low pH and high lactic acid level of the ruminal fluid in SARA cattle.

We investigated the effect of repeated subacute ruminal acidosis (SARA) challenges on the pH, fermentative function, and bacterial community in the rumen. Four rumen-cannulated Holstein bulls were fed a high-forage diet for 7 d (HF period) followed by a high-grain diet for 7 d (HG period). Four SARA challenges were carried out consecutively (first, second, third, and fourth challenges). The ruminal pH was measured continuously during the experiment, and rumen fluid samples during the first to fourth challenges were collected at 0800, 1400, and 2000 h on the last days of each feeding period for analysis; volatile fatty acid components, NH3-N, and lactic acid concentrations were measured. Bacterial community structure was analyzed at 0800 h during the first and fourth challenges on the last days of each period. The 24-h mean ruminal pH was decreased during the transition from high-forage to high-grain diet and tended to differ between the HF and HG periods. During the HG period, ruminal pH

To estimate the glomerular filtration rate (GFR) in cynomolgus monkeys (Macaca fascicularis), a three-blood-sample method using iodixanol was assessed in comparison with the conventional multisample strategy using inulin. Iodixanol and inulin were coadministered intravenously 40 mg I/kg and 50 mg/kg, respectively, to male monkeys, followed by blood collection 60, 90 and 120 min later. A close correlation (r=0.96) was noted between the GFR values estimated by both methods. In clinically healthy monkeys, the basal values were determined to be 3.06 ± 0.50 ml/min/kg. This is the first report, suggesting that serum clearance of iodixanol is a ready-to-use tool for a screening the GFR in monkeys, although it is necessary to perform a more longitudinal study using animals with reduced renal function.

Eight Holstein calves (10 ± 3 weeks) were used to examine the interaction between a bacteria-based probiotic agent (probiotic) and the function of peripheral blood mononuclear cells (PBMCs). The probiotic, consisting of Lactobacillus plantarum, Enterococcus faecium and Clostridium butyricum, was administered orally at 3.0 g/100 kg body weight to calves once daily for 5 consecutive days. Calves given the vehicle alone with no probiotic served as the control. In the treatment group, increases in numbers of CD282(+) (TLR2) monocytes, CD3(+) T cells and CD4(+), CD8(+) and WC1(+) γδ T cell subsets were noted on day 7 post-placement compared to predose day and the control group. Expression of interleukin (IL)-6, interferon-gamma (INF-γ) and tumor necrosis factor-alpha (TNF-α) was elevated in peripheral leukocytes on days 7 and 14. These results suggest that peripheral blood leukocytes in healthy calves may be stimulated via the gastrointestinal microbiota, which was increased by the oral probiotic treatment, with overall stability of the rumen bacterial flora. The 5-day repeated administration of a bacteria-based probiotic may enhance cellular immune function in weaned calves.

This study was performed to clarify whether a formula (Holstein equation) based on a single blood sample and the isotonic, nonionic, iodine contrast medium iodixanol in Holstein dairy cows can apply to the estimation of glomerular filtration rate (GFR) for beef cattle. To verify the application of iodixanol in beef cattle, instead of the standard tracer inulin, both agents were coadministered as a bolus intravenous injection to identical animals at doses of 10 mg of I/kg of BW and 30 mg/kg. Blood was collected 30, 60, 90, and 120 min after the injection, and the GFR was determined by the conventional multisample strategies. The GFR values from iodixanol were well consistent with those from inulin, and no effects of BW, age, or parity on GFR estimates were noted. However, the GFR in cattle weighing less than 300 kg, aged

We investigated the relationship between ruminal pH and bacteria in calves fed calf starter with and without forage during weaning transition. First, 16 Holstein bull calves were obtained from dairy farms and equipped with rumen cannulas by cannulation surgery. Then, calves (73.5 ± 4.2 kg; mean ± SE) were assigned to groups fed calf starter either with forage (HAY, n = 8) or without forage (CON, n = 8), and all calves were weaned at 8 weeks of age. Ruminal pH was measured continuously, and rumen fluid samples were collected at 7, 8, 9, and 11 weeks of age, namely −1, 0, 1, and 3 weeks after weaning, respectively, to assess volatile fatty acid concentrations and bacterial DNA. The 24-h mean ruminal pH was significantly (P < 0.05) different between the two groups. Diurnal changes in the 1-h mean ruminal pH were observed throughout the study in the HAY group; however, they were not observed at 0 and 1 weeks after weaning in the CON group. Moreover, the HAY group had significantly (P < 0.05) higher proportions of acetate and butyrate and lower proportion of propionate, and significantly (P < 0.05) lower ruminal acetate-to-propionate ratios were observed in the CON group. The ruminal bacterial diversity indices decreased after −1 week in both groups and increased at 0 and 1 weeks after weaning in the HAY and CON groups, respectively. From the 454 pyrosequencing analysis, significant differences (P < 0.05) were observed in the relative abundance of several phyla (Bacteroidetes, Actinobacteria, and Tenericutes) and one genus (Prevotella) between the two groups. From quantitative real-time PCR analysis, the HAY group had the higher copy numbers of cellulolytic bacteria (Ruminococcus flavefaciens and Ruminococcus albus) compared with the CON group. This study demonstrated that feeding of dietary forage alleviates subacute ruminal acidosis due to diurnal changes in ruminal pH. Furthermore, changes in ruminal pH affect the ruminal bacterial diversity and relative abundance, and these changes might have influenced the establishment of fermentative ruminal functions during weaning transition.

To clarify the effect of renal dysfunction on pharmacokinetics of the prokinetic agent metoclopramide (MCP), we administered intravenously 0.4 mg/kg MCP to healthy calves and calves subjected to right kidney vessel ligation (ligation) without or with a subsequent left nephrectomy (ligation plus removal). Plasma MCP concentration, glomerular filtration rate (GFR) and plasma prolactin level were measured by liquid chromatography-tandem mass spectrometry, simplified equation using iodixanol and enzyme-linked immunosorbent assay, respectively. Only in calves with ligation plus removal, plasma MCP concentrations were increased significantly 6, 8 and 12 hr after injection, showing that a negative correlation was observed between the plasma MCP concentrations and GFR value. A tendency to increase in plasma PRL concentration was noted also in these calves. In conclusions, plasma MCP concentrations depend on the GFR mode in calves, and its critical GFR value was estimated.

We examined the correlation between the glomerular filtration rate (GFR) estimated from an equation based on the serum iodixanol clearance technique and International Renal Interest Society (IRIS) stages of chronic kidney disease (CKD) in cats. The equation included the injection dose, sampling time, serum concentration and estimated volume of distribution (Vd) of the isotonic, nonionic, contrast medium iodixanol as a test tracer. The percent changes in the median basal GFR values calculated from the equation in CKD cats resembled those of IRIS stages 1–3. These data validate the association between the GFR derived from the simplified equation and IRIS stages based on the serum creatinine concentration in cats with CKD. They describe the GFR ranges determined using single-sample iodixanol clearance for healthy cats and cats with various IRIS stages of CKD.

Adult schistosomes were detected in the veins or capillaries of the large intestine, mesentery, liver, and adrenal glands in eight of 13 whooper swans (Cygnus cygnus) examined in Iwate Prefecture, Japan. However, neither eggs nor severe tissue injuries were observed in any of the swans. The schistosomes were definitively identified as Allobilharzia visceralis based on the nucleotide sequences of the ribosomal internal transcribed spacer (ITS) region. Allobilharzia visceralis infections have been reported in whooper swan in Iceland and tundra swan (Cygnus columbianus) in North America. These detections suggest that A. visceralis is distributed extensively along the swan flyways because the swans are migratory birds. To the best of our knowledge, this is the first report of A. visceralis infection in Asia.

The vertical transmission of Mycoplasma (M.) wenyonii was investigated in beef cattle raised on a farm in Japan by analysing the ribonuclease P RNA (rnpB) gene sequence using PCR. Peripheral blood samples from 17 dams infected with M. wenyonii and from their neonatal calves were collected and colostrum samples were taken from cows immediately after parturition, and subsequently the blood samples of calves were monitored continuously for three months. At birth on day 0, although no rnpB gene was detected in the colostrum of any of the dams, four (23.5%) of the 17 calves born were positive. At three months after delivery, the number of positive calves decreased to three. Although horizontal transmission by blood-feeding arthropod vectors has been basically accepted as the most common route of haemoplasma infection, these findings suggest that vertical transmission is, at least in part, another most likely route of M. wenyonii infection in cattle.

To estimate the glomerular filtration rate (GFR) in cynomolgus monkeys (Macaca fascicularis), a three-blood-sample method using iodixanol was assessed in comparison with the conventional multisample strategy using inulin. Iodixanol and inulin were coadministered intravenously 40 mg I/kg and 50 mg/kg, respectively, to male monkeys, followed by blood collection 60, 90 and 120 min later. A close correlation (r=0.96) was noted between the GFR values estimated by both methods. In clinically healthy monkeys, the basal values were determined to be 3.06 ± 0.50 ml/min/kg. This is the first report, suggesting that serum clearance of iodixanol is a ready-to-use tool for a screening the GFR in monkeys, although it is necessary to perform a more longitudinal study using animals with reduced renal function.

To clarify the pathophysiology of left displaced abomasum (LDA), beef cattle fed high-starch diets were examined. The abomasal pH in beef cattle with LDA was lower than that in non-LDA reference animals (data from beef cattle at an abattoir), suggesting that it facilitated acidity. Bacteriological examinations of the abomasal fluid in cattle with LDA revealed the presence of Pseudomonas spp., Clostridium spp. and Candida spp., presumably reflecting the accelerated influx of ruminal fluid into the abomasum. Biochemical analyses of serum revealed that LDA cattle had higher lactic acid and lower vitamin A and E levels than non-LDA reference animals. These results indicate that beef cattle with LDA may suffer from vitamin A and E deficiencies due to maldigestion of starch and the high acidity of abomasal fluid.