Oral ingestion of collagen peptide causes change in width of the perimysium of the chicken iliotibialis lateralis muscle

Skeletal muscle is mainly composed of myofibers and intramuscular connective tissue. Bundles composed of many myofibers, with each myofiber sheathed in connective tissue called the endomysium, are packed in the perimysium, which occupies the vast bulk of the intramuscular connective tissue. The perimysium is a major determination factor for muscle texture. Some studies have reported that collagen peptide (Col-Pep) ingestion improves the connective tissue architecture, such as the tendon and dermis. The present study evaluated the effects of Col-Pep ingestion on the chicken iliotibialis lateralis (ITL) muscle. Chicks were allocated to three groups: the 0.15% or 0.3% Col-Pep groups and a control group. Col-Pep was administered by mixing in with commercial food. On day 49, the ITL muscles were analyzed by morphological observation and the textural property test. The width of the perimysium in the 0.3% Col-Pep group was significantly larger than other two groups. Although scanning electron microscopic observations did not reveal any differences in the architecture of the endomysium, elastic improvement of the ITL muscle was observed as suggested by an increase of the width of perimysium and improved rheological properties. Our results indicate that ingestion of Col-Pep improves the textural property of ITL muscle of chickens by changing structure of the perimysium.     

Cytoskeletal and mitochondrial properties of bovine oocytes obtained by Ovum Pick‐Up: the effects of follicle stimulation and in vitro maturation

Follicle stimulation by follicular stimulating hormone (FSH) is known to improve developmental competence of bovine oocytes obtained by Ovum Pick‐Up (OPU); however, the exact factors in oocytes affected by this treatment have remained unclear. We compared in vitro matured (IVM) oocytes obtained at the immature stage from cows by OPU either without or with stimulation with FSH (non‐stimulated and stimulated OPU, respectively) to those obtained by superstimulation and in vivo maturation in terms of cytoskeleton morphology, mitochondrial distribution, intracellular adenosine triphosphate (ATP) content and H₂O₂ levels at the metaphase‐II stage and intracellular Ca²⁺ levels after in vitro fertilization (IVF). Confocal microscopy after immunostaining revealed reduced size of the meiotic spindle, associated with increased tendencies of microfilament degradation and insufficient mitochondrial re‐distribution in non‐stimulated OPU‐derived IVM oocytes compared with those collected by stimulated OPU, which in turn resembled in vivo matured oocytes. However, there was no difference in mitochondrial functions between oocytes obtained by stimulated or non‐stimulated OPU in terms of ATP content, cytoplasmic H₂O₂ levels, base Ca²⁺ levels and the frequencies and amplitudes of Ca²⁺ oscillations after IVF. Larger size of metaphase spindles in oocytes obtained by stimulated OPU may reflect and potentially contribute to their high developmental competence.     

Digestive,fermentative, and physical properties of pineapple residue as a feed for cattle

The intake, digestion, and ruminal fermentation properties; the antioxidative activity; and the physical effectiveness of pineapple residue (PR) from the cut-fruit industry as a feed for cattle were investigated. Four nonlactating Holstein cows were fed a basal diet and diets with 1.4- and 3.6-kg dry matter (DM)/day of PR (low-PR and high-PR diets, respectively). The DM digestibility and total digestible nutrients were 71% and 70%, respectively. Ruminal pH, volatile fatty acids, and ammonia-N did not differ among the diets. The numbers of total viable, amylolytic, cellulolytic, and methanogenic bacteria and protozoa, and microbial protein synthesis in the rumen also did not differ significantly. Blood triglyceride, nonesterified fatty acids, urea nitrogen, and aspartate transaminase were lower in the high-PR diet. Feeding PR did not affect blood malondialdehyde, although PR has a higher antioxidative value than other commonly used feeds. The particle distribution of PR satisfied the recommended range for haylage. The chewing time for ingestion and rumination did not change with PR content, and the roughage value index of PR was 57-min/kg DM. These results suggest that PR has good intake and digestion properties and satisfactory physical effectiveness. Even a high-PR-content feed unlikely induces the risk of ruminal acidosis.     

Estimation of shear strength of dowel-type timber connections with multiple slotted-in steel plates by European yield theory

The shear strength of dowel-type timber connections with multiple slotted-in steel plates was estimated based on European yield theory. The values calculated based on the yield theory were compared with experimentally obtained results. An experiment was performed on dowel-type timber connections with two and three slottedin steel plates under lateral loads parallel to the grain. The yield mode of the dowel-type connection assumed in this study corresponds approximately to the failure mode of the connection obtained from the experiment. The shear strength of the dowel-type connections calculated based on the yield theory showed good agreement with the results for shear strength obtained in the experiment. The yield theory was useful for estimating the shear strength of the doweltype connection with multiple slotted-in steel plates. The shear strength of the dowel-type connection was greatly affected by the spacing of the steel plates, the number of steel plates, and the timber thickness. The values of these parameters that showed the proper shear strength of the dowel-type connection could be estimated based on the yield theory. Part of this paper was presented at the 9th Timber Engineering Forum of the Japan Timber Engineering Society, December 2005     

Determination of embedding strength of wood for dowel-type fasteners

Embedding tests parallel and perpendicular to the grain were conducted to produce a database of embedding strength of wood for the design of dowel-type joints. Dowel diameters were 8,12,16, and 20mm. Embedding strength was evaluated by the 5% off-set method and a maximum load up to 5mm displacement according to EN383. The embedding strength parallel to the grain evaluated by the former method showed values close to those obtained with the latter method, but they showed a significant difference in tests conducted perpendicular to the grain. The embedding strength parallel to the grain was 0.9 times as large as the compressive strength parallel to the grain regardless of the evaluation method. The embedding strength perpendicular to the grain evaluated by the 5% off-set method was four times as large as the compressive strength perpendicular to the grain. When the embedding strength perpendicular to the grain was evaluated by a maximum load up to 5mm displacement according to EN383, the ratio of embedding strength perpendicular to the grain to the compressive strength perpendicular to the grain decreased as the dowel diameter increased.Part of this paper was presented at the annual meeting of the Architectural Institute of Japan 1999, Hiroshima, September 1999; the 50^th annual meeting of the Japan Wood Research Society, Kyoto, April 2000; and the World Conference on Timber Engineering 2000, Whistler, Canada, July–August, 2000     

Estimation of yield and ultimate strengths of bolted timber joints by nonlinear analysis and yield theory

A finite element nonlinear analysis was conducted on bolted timber joints under lateral loads parallel and perpendicular to the grain. The results obtained from this analysis were compared with the experimental results and calculated values based on the yield theory. The analysis and experiment were performed on double shear bolted joints parallel and perpendicular to the grain with steel side plates and a slotted-in steel plate. It was found from the analysis that the yielding of wood and bolt occurred before the overall yielding of the bolted joint. Shear strength of bolted joints calculated from the yield theory using the embedding yield strength of wood and the yield moment of the bolt showed comparatively good agreement with the shear strength evaluated by 5% offset of the load–slip curve in the experiment and analysis. The shear strength of the bolted joint calculated from the yield theory using the embedding ultimate strength of wood and the ultimate moment of the bolt agreed quite well with the shear strength evaluated by the maximum load up to 15mm slip in the analysis. The former, parallel and perpendicular to the grain, were 11% and 34%, on average smaller than the latter in the experiment.Part of this paper was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002; the Annual Meeting of Architectural Institute of Japan 2002, Ishikawa, August 2002; and the World Conference on Timber Engineering 2002, Shah Alam, Malaysia, August 2002     

Comparison of Pathogenicity and Nucleotide Sequences of 3′-terminal Regions of Bean yellow mosaic virus Isolates from Gladiolus

Sixty-four isolates of Bean yellow mosaic virus (BYMV) from cultivated and naturalized gladioli were divided into two pathogenic groups, necrotic spot (NS) and chlorotic spot (CS) groups on Chenopodium quinoa. NS-type isolates (S-22N and E-24N), CS-type isolates (S-22C and E-92C), and broad bean isolates (Sb-50C and Sb-12C) differed in their pathogenicity on Antirrhinum majus, Nicotiana benthamiana, Phaseolus vulgaris, Spinacia oleracea and Vigna unguiculata. The four gladiolus isolates were different from BYMV-B, -P, -O and C1YVV-N in their pathogenicity on these plants, while the two broad bean isolates were similar to BYMV-B, originally from broad bean. The nucleotide (nt) sequences of the 3′-terminal region of the BYMV RNA genome of the two NS-type isolates, the two CS-type isolates, the two broad bean isolates and BYMV-B, -P and -O were determined. In a phylogenetic tree based on the CP amino acid (aa) sequences, the two NS-type isolates clustered together (identity 98.4% and 98.2% at the nt and aa level, respectively). The two CS-type isolates clustered with BYMV-O (93.2 to 99.3% nt identity and 95.6 to 98.5% aa identity). The two broad bean isolates clustered with BYMV-B (99.0 to 99.5% nt identity and 98.9 to 99.6% aa identity). BYMV-P clustered with BYMV-CS (identity 97.7% and 99.3% at the nt and aa level, respectively). The obtained sequences were compared with those of the 3′-terminal regions of seven published BYMV isolates. In a phylogenetic tree based on deduced aa sequences, BYMV isolates were divided into four clusters. Received 1 July 1999/ Accepted in revised form 22 May 2000