Lactobacillus ingluviei C37 from chicken inhibits inflammation in LPS‐stimulated mouse macrophages

Probiotics are growing alternatives to antibiotics, and can contribute to the prevention and treatment of diseases and enhance livestock production. Lactobacillus (L.) ingluviei is a novel probiotic species with growth‐enhancement effects; however, this species remains poorly understood, and there have been (to our knowledge) no studies focusing on its immunological effects. Here, we isolated L. ingluviei C37 (LIC37) from chicken and evaluated the bacterium's immunomodulatory properties to explore its probiotic potential. Real‐time quantitative PCR and ELISA showed that in vitro exposure of inflammation‐stimulated mouse peritoneal macrophages to heat‐killed LIC37 led to decreases in tumor necrosis factor‐α and interleukin (IL)‐6 levels and an increase in IL‐10. These findings suggested that LIC37 exerts anti‐inflammatory effects by modulating cytokine profiles. This species may be an attractive probiotic bacterial strain for use in animal production.     

Increase in minimal residual disease in peripheral blood before clinical relapse in dogs with lymphoma that achieved complete remission after chemotherapy

Background: We developed previously a minimal residual disease (MRD) monitoring system in dogs with lymphoma by exploring a highly sensitive real‐time PCR system. Objectives: To identify the change in MRD before clinical relapse in dogs with lymphoma that achieved complete remission after chemotherapy. Animals: Twenty dogs with multicentric high‐grade B‐cell lymphoma. Methods: MRD levels in peripheral blood mononuclear cells (PBMCs) were measured by real‐time PCR amplifying the rearranged immunoglobulin heavy chain gene. MRD measurement and clinical assessment were performed every 2–4 weeks for 28–601 days after completion of chemotherapy. An increase in MRD was defined as an increase by more than 0.5, calculated by log₁₀[copy number of MRD per 10⁵ PBMCs], based on the uncertainty level observed in a canine lymphoma cell line. Results: During the follow‐up period, 15 dogs relapsed in 28–320 days (median, 120 days) after completion of chemotherapy. An increase in MRD was detected 2 weeks or more before relapse in 14 of the 15 dogs, but an increase in MRD before relapse could not be detected in the remaining 1 dog. The time from increased MRD to clinical relapse was 0–63 days (median, 42 days). In contrast, no increase in MRD was detected in 5 dogs that did not experience clinical relapse. Conclusion and Clinical Importance: An increase in MRD can be detected before clinical relapse in dogs with lymphoma. Application of early reinduction therapy based on an increase in MRD before clinical relapse may improve treatment outcome in canine lymphoma.     

Evaluation of cytoreductive efficacy of vincristine, cyclophosphamide, and Doxorubicin in dogs with lymphoma by measuring the number of neoplastic lymphoid cells with real-time polymerase chain reaction

Background: The cytoreductive efficacy of the individual components of multidrug chemotherapy for canine lymphoma is difficult to evaluate after complete remission. Objectives: To compare the cytoreductive efficacy of vincristine (VCR), cyclophosphamide (CPA), and doxorubicin (DXR) in dogs that received a 6‐month modified version of the University of Wisconsin‐Madison chemotherapy protocol (UW‐25). Animals: Twenty‐nine dogs with high‐grade B‐cell multicentric lymphoma. Methods: Rearranged immunoglobulin heavy chain gene fragments from lymphoma cells were amplified by polymerase chain reaction (PCR) and sequenced to prepare clone‐specific primers and probes for real‐time PCR. The number of lymphoma cells in peripheral blood was measured from diagnosis to week 11 of UW‐25. Results: The number of lymphoma cells after the 1st administration of VCR, CPA, and DXR in weeks 1–4 was decreased in 29/29 (100%), 15/29 (51.7%), and 26/27 (96.3%) dogs, respectively. The cytoreductive efficacy of CPA was less than that of VCR and DXR. VCR, CPA, and DXR administered in weeks 6–9 were effective in 5/26 (19.2%), 5/20 (25.0%), and 14/19 (73.7%) dogs, respectively, indicating the sustained cytoreductive efficacy of DXR. CPA nonresponders were heavier and exhibited a shorter 1st remission than CPA responders. Conclusion and Clinical Importance: When using UW‐25 for treatment of canine lymphoma, CPA was found to have less cytoreductive efficacy than VCR and DXR. Real‐time PCR‐based quantification of tumor cells is an objective marker of the efficacy of chemotherapeutic agents.     

Serum clearance of iodixanol for estimating glomerular filtration rate in calves

To evaluate serum clearance of iodixanol, applicable to the estimation of glomerular filtration rate (GFR), clinically healthy and experimentally-induced nephropathy calves were prepared. Iodixanol was administered intravenously at 40 mg I/kg, and blood was withdrawn 60, 120, and 180 min later. Serum iodixanol concentration was determined by high-performance liquid chromatography. No statistical difference in GFR was noted between strains (Holstein vs. Japanese Black) or sexes, and the α(2)-adrenergic agonist xylazine increased GFR. In calves subjected to right renal vessel ligation, followed by a left nephrectomy, a marked reduction in GFR was observed with renal ischemic changes. These results suggest that the GFR estimation by serum iodixanol clearance is a ready-to-use tool in calf research and practice owing to the ease of monitoring serial renal function.     

Antibody responses induced by Japanese whole inactivated vaccines against equine influenza virus (H3N8) belonging to Florida sublineage clade2

In 2010, the World Organisation for Animal Health recommended the inclusion of a Florida sublineage clade2 strain of equine influenza virus (H3N8), which is represented by A/equine/Richmond/1/07 (Richmond07), in equine influenza vaccines. Here, we evaluate the antigenic differences between Japanese vaccine strains and Richmond07 by performing hemagglutination inhibition (HI) assays. Ferret antiserum raised to A/equine/La Plata/93 (La Plata93), which is a Japanese vaccine strain, reacted with Richmond07 at a similar titer to La Plata93. Moreover, two hundred racehorses exhibited similar geometric mean HI antibody titers against La Plata93 and Richmond07 (73.1 and 80.8, respectively). Therefore, we can expect the antibody induced by the current Japanese vaccines to provide some protection against Richmond07-like viruses.     

Toxicological pathology in the rat placenta

The placenta grows rapidly for a short period with high blood flow during pregnancy and has multifaceted functions, such as its barrier function, nutritional transport, drug metabolizing activity and endocrine action. Consequently, the placenta is a highly susceptible target organ for drug- or chemical-induced adverse effects, and many placenta-toxic agents have been reported. However, histopathological examination of the placenta is not generally performed, and the placental toxicity index is only the placental weight change in rat reproductive toxicity studies. The placental cells originate from the trophectoderm of the embryo and the endometrium of the dam, proliferate and differentiate into a variety of tissues with interaction each other according to the development sequence, resulting in formation of a placenta. Therefore, drug- or chemical-induced placental lesions show various histopathological features depending on the toxicants and the exposure period, and the pathogenesis of placental toxicity is complicated. Placental weight assessment appears not to be enough to evaluate placental toxicity, and reproductive toxicity studies should pay more attention to histopathological evaluation of placental tissue. The detailed histopathological approaches to investigation of the pathogenesis of placental toxicity are considered to provide an important tool for understanding the mechanism of teratogenicity and developmental toxicity with embryo lethality, and could benefit reproductive toxicity studies.     

Follicular persistence induced by adrenocorticotropic hormone administration in goats

The objective of the present study was to examine the effect of adrenocorticotropic hormone (ACTH) administration on the induction of persistent cystic follicle in the goat in order to establish a method to experimentally induce cystic follicle. Four cross-bred goats were intramuscularly administered ACTH at 0.78 and 6.25 μg/10 kg twice a day from Days 15 to 21 (Day 0 was defined as the day of last estrus). Follicular status in the ovary was monitored by ultrasound examination. The plasma concentrations of estradiol, progesterone and cortisol were measured. Treatment with ACTH at the 0.78 and 6.25 μg/10 kg levels caused persistent follicles (> 10 days delay from the expected ovulation date) in 50% of the goats in both treatment groups. In those animals, ovulation occurred 17 and 27 days and 11 and 12 days after the expected days in the 0.78 and 6.25 μg/10 kg groups, respectively. The maximum follicle diameters were 10 and 9 mm in the 0.78 and 6.25 μg/10 kg ACTH groups, respectively. In the control group, the estradiol concentration increased on Day 18 and remained at a high level for a few days. However, such an increase was not seen in both ACTH groups. The estradiol concentration increased gradually from Days 21 to 27 in the 6.25 μg/10 kg ACTH group. These results suggest the possibility that ACTH induces persistent follicles in goats, which may be related to the delay of the onset of estradiol secretion followed by its maintenance at a high concentration.     

Evaluation of the Usefulness of a PCR Assay Performed at a Clinical Laboratory for the Diagnosis of Respiratory Disease Induced by Equine Herpesvirus Type 1 in the Field

A PCR assay for the diagnosis of respiratory disease induced by equine herpesvirus type 1 (EHV-1) was performed at the clinical laboratory in the Racehorse Clinic of the Ritto Training Center of the Japan Racing Association from December 2007 to March 2008. The assay was performed without the trouble of contamination throughout the study and its turnaround time was approximately 6 hr. The PCR detection rates of EHV-1 among seroconverted horses were 22.2% for nasal swabs and 33.3% for blood samples. However, EHV-1 DNA was also detected in horses without seroconversion at a low rate. These results indicated that the PCR assay should be used as an adjunct method, but would help to make an early diagnosis of EHV-1 infection.     

Gray mold of yacon and sunflower caused by Botrytis cinerea

Severe wilt and blight of entire plants of yacon (Smallanthus sonchifolius) grafts on sunflower (Helianthus annuus) were found in greenhouses in Kagawa Prefecture in the southwest region of Japan from April to May between 1997 and 1999. A mitosporic fungus, isolated repeatedly from the diseased plants and identified as Botrytis cinerea, was demonstrated to be virulent to both yacon and sunflower. The new disease on yacon was named gray mold of yacon. The disease on sunflower, gray mold of sunflower, is new to Japan.