Differential cytokine expression in T cell subsets from bovine peripheral blood

Although distinct cytokine expression in T cell subsets is well understood in mice and humans, limited information is available on bovine T cell subsets. In the present study, we analyzed the mRNA expression of 10 kinds of cytokines and CD25 expression in CD4⁺, CD8⁺, WC1⁺ and WC1^-γδ T cell subsets in bovine peripheral blood by Concanavalin A (Con A) stimulation. CD25 expression was significantly increased in CD4⁺, CD8⁺ and WC1⁺γδ T cells, but not in WC1^-γδ T cells by Con A stimulation. In CD4⁺ T cells, the mRNAs of Interleukin (IL)-2, IL-6, IL-10, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, TNF-β and transforming growth factor (TGF)-β were expressed in control cultures, and IL-3, IL-4 and granulocyte-macrophage colony stimulating factor (GM-CSF) were newly expressed when the cells were stimulated with Con A. CD8⁺ T cells expressed the mRNAs of IL-6, TNF-α, TNF-β and TGF-β in control cultures, and newly expressed those of IL-2, IFN-γ and GM-CSF, but did not express those of IL-3, IL-4 or IL-10 after Con A stimulation. The cytokine expression profile of WC1⁺γδ T cells was similar to that of CD8⁺ T cells. However, WC1^-γδ T cells did not express any cytokine mRNA except TGF-â mRNA. These results will contribute to elucidate the participation of T cell subsets in immune responses against infectious disease in cattle.     

Evaluation of basal media for micropropagation of four highbush blueberry cultivars

Murashige and Skoog medium (MS), woody plant medium (WPM), and a mixture of equal parts of MS and WPM (MW) were compared for in vitro shoot proliferation and rooting of four highbush blueberry (Vaccinium spp.) cultivars. During the multiplication stage, the shoots on WPM showed worse growth than the other shoots. The MW produced the best shoot growth. The shoots on MS grew well but tended toward hyperhydricity in the multiplication stage, especially in the case of ‘Bluecrop’ shoots. Rooting was worst in the shoots multiplied on WPM, while the best rooting percentage of ‘Bluecrop’ shoots was obtained on MS, and that of ‘O’Neal’ on MW. The rooted shoots developed a good root system and were easily acclimatized after potting.     

Presence of neuropeptide Y in somatotrophs of cattle

Neuropeptide Y (NPY), a 36-amino acid member of the pancreatic polypeptide family, was found to be present by immunohistochemistry in the bovine adenohypophysis. NPY mRNA expression was confirmed in the adenohypophysis by RT-PCR. NPY immunoreactivity was present in about 38% of adenohypophyseal cells in the pars distalis. However, NPY immunoreactive cells (NPY-ir cells) were scarce in the zona tuberalis. Immunohistochemistry of NPY and specific hormones using mirror sections revealed that NPY was colocalized in GH immunoreactive cells. Over 90% of somatotrophs corresponded to NPY-ir cells. These results indicate that endogenous NPY is present in the bovine somatotroph and may act as an endocrine intercellular mediator in the adenohypophysis.     

Epidemiological study on BSE outbreak in Japan

The aim of this study is to identify, as hypotheses, all feasible sources and routes of infection for the BSE cases in Japan, and to study the probability of each hypothesis. The strategy of this epidemiological study is as follows. 1) BSE risk status in Japan is tentatively divided into 3 stages, i.e., before 1996 April when administrative guidance for feed ban of cattle MBM introduced. After that to 2001 September, the first case of BSE in Japan, then, after 2001 October with real feed ban in the law. 2) Make hypotheses depending on the invasive risk scenarios and propagation risk of BSE in Japan, and they are checked by evidences, case control study or statistics. 3) Grouping of BSE cattle was conducted time sequentially and spatially; that is Group-A (1995-96, born in Hokkaido, Kanto), Group-B (1999 in Kyushu), Group-C (1999-2001 in Hokkaido), Group-D (young cattle born after real feed ban) and Pre-A, Post-D groups. As a result, a milk replacer was considered one of the most probable cause of group-A contamination, and group-C outbreak might be caused by an indigenous BSE propagation of group-A in Hokkaido. If the hypothesis of Holland animal fat as causative material was accepted, however, there are several unexplainable points. Collection of scientific evidences on animal fat impurity and age dependent susceptibility to BSE will be needed to clarify the true causative material.     

Intraoperative acridine orange photodynamic therapy and cribriform electron-beam irradiation for canine intranasal tumors: A pilot study

Untreated canine intranasal tumors carry a poor prognosis. We retrospectively evaluated the efficacy of marginal tumor resection in combination with intraoperative acridine orange (AO) photodynamic therapy (PDT) and 1 fraction of 5 Gy megavoltage irradiation for canine intranasal malignant tumors. When cribriform plate invasion or turbinate destruction around the cribriform plate was present, an additional fraction of 20 Gy was delivered with an electron beam during surgery. The study included 6 dogs, 2 of which were classified as stage I, 1 as stage II, and 3 as stage IV. The median local disease-free survival time and overall survival after the treatment were 8.5 and 13 months, respectively. Recurrence was noted in 2 of the 6 dogs after 4 and 7 months. Adverse events were mild (subcutaneous emphysema in 1 case, and rhinitis in 3 cases). Combination AO therapy may increase the tumor control time of dogs with marginally resectable intranasal malignant tumors.     

Spatial relationships among the cellular tapetum,visual streak and rod density in dogs

The dog visual system is well suited to dim light conditions due to rod-dominated retina and the reflective tapetum. The topographical distributions of rods and thickness of the tapetum of the dog were quantified in retinal whole mounts stained with thionine, and spatial relationships among the tapetum, rod density and visual streak of high ganglion cell density were elucidated. The relationship between the retina and tapetum was analyzed in parasagittal sections stained with thionine or hematoxylin-eosin. The tapetum was thick in its center, and the thickest part consisted of 9 to 12 tapetal cell layers. Rod density ranged from 200,000 to 540,000/mm². Maximum rod density was found in the area dorsal to the visual streak, and the density in that area was significantly higher than the rod density in the visual streak and accorded spatially with the thickest part of the tapetum. The horizontal visual streak was found over the horizontal line through the optic disc in the temporal half and extended slightly into the nasal half. The central area of the highest density of ganglion cells was approximately located midway between the nasal and temporal ends of the visual streak. The visual streak was located within the tapetal area, but ventrally to the thick part of the tapetum.     

Toxoplasma gondii seroprevalence in domestic animals and humans in Mymensingh District, Bangladesh

The seroprevalence of Toxoplasma gondii was examined in adult women and domestic animals used for meat products from the Mymensingh District, Bangladesh. Cattle, goats and sheep showed a high seroprevalence (12, 32 and 40%, respectively), while the sera from all fifteen women examined in the same area were seronegative. Considering that primary infection in women during pregnancy can cause abortion and congenital defects, accidental ingestion of T. gondii infected meat products from domestic animals represents a risk factor for adult women living in the same area.     

Effects of feeding early‐harvested orchardgrass–perennial ryegrass mixed silage instead of heading stage harvested timothy silage on digestion and milk production in dairy cows

We evaluated the effects of replacement of heading stage harvested timothy silage with early‐harvested orchardgrass–perennial ryegrass mixed (OP) silage while maintaining or reducing concentrate input on dry matter intake (DMI), milk production, nutrient digestibility, and N balance in dairy cows. Nine multiparous Holstein cows were used in a replicated 3 × 3 Latin square design with three dietary treatments: TYL, a diet containing timothy silage where forage‐to‐concentrate ratio (FC) was 50:50; OPL, a diet containing OP silage where FC ratio was 50:50; and OPH, a diet containing OP silage where FC ratio was 60:40. We observed that an equal replacement of timothy with OP silage increased DMI, milk yield, milk protein production, and nutrient digestibility but decreased milk fat content (TYL versus OPL). We observed that replacing timothy with OP silage while reducing concentrate input increased milk fat and protein yield, nutrient digestibility, and feed efficiency and reduced urinary N loss with no effect on DMI or milk fat content (TYL versus OPH). These results show that replacing timothy with OP silage can be a good approach to improve milk production, feed efficiency, and N utilization and reduce concentrate input. However, milk fat depression should be considered when an equal substitution is performed.     

Development of cleaved amplified polymorphic sequence (CAPS)-based markers for identification of sweetpotato cultivars

To develop a simple and reliable method to identify sweetpotato cultivars, we designed cleaved amplified polymorphic sequence (CAPS)-based markers and used them to perform genotyping of Japanese sweetpotato cultivars. In order to screen the CAPS-based markers, 13 primer pairs were designed from the exon sequences of 11 sweetpotato genes to amplify fragments containing an intron. By digesting the amplified products with 8 restriction enzymes having different recognition sites, a total of 27 polymorphic marker fragments were obtained. Genotyping of 60 Japanese sweetpotato cultivars using these markers suggested that the markers can effectively distinguish sweetpotato cultivars. Among the genes used for primer design, the gene encoding the dihydroflavonol 4-reductase (DFR) showed the largest degree of polymorphism. To our knowledge, this is the first report on the development of CAPS-based markers in sweetpotato.