Comparison of the effects explained by variations in the bovine PLAG1 and NCAPG genes on daily body weight gain,linear skeletal measurements and carcass traits in Japanese Black steers from a progeny testing program

The c.1326T>G single nucleotide polymorphism (SNP) in the NCAPG gene, which leads to an amino acid change of Ile442 to Met442, was previously identified as a candidate causative variation for a bovine carcass weight quantitative trait loci (QTL) on chromosome 6, which was associated with linear skeletal measurement gains and daily body weight gain at puberty. Recently, we identified the stature quantitative trait nucleotides (QTNs) in the PLAG1‐CHCHD7 intergenic region as the causative variations for another carcass weight QTL on chromosome 14. This study aimed to compare the effects of the two QTL on growth and carcass traits using 768 Japanese Black steers from a progeny testing program and to determine whether a genetic interaction was present between them. The FJX_250879 SNP representing the stature QTL was associated with linear skeletal measurements and average daily body weight gain at early and late periods during adolescence. A genetic interaction between FJX_250879 and NCAPG c.1326T>G was detected only for body and rump lengths. Both were associated with increased carcass weight and Longissimus muscle area, and NCAPG c.1326T>G was also associated with reduced subcutaneous fat thickness and increased carcass yield estimate. These results will provide useful information to improve carcass weight in Japanese Black cattle.     

Spatial distribution and feeding habits of Pacific cod (Gadus macrocephalus) larvae in Mutsu Bay, Japan

The spatial distributions and feeding habits of Pacific cod ( Gadus macrocephalus ) larvae, and the spatial distributions of copepod nauplii and copepodites, their main prey, were examined in Mutsu Bay from February to March during 1989–92. Yolk-sac larvae were caught at 30–45 m depth at the bay mouth. Larvae without yolk were collected at 8–45 m depth at the bay mouth and the inner part of the bay, and large larvae were chiefly found in the bay. This geographical pattern in larval size may have been because of transport to the inner part of Mutsu Bay by the Tsugaru Warm Current. The dominant taxa of copepod nauplii and copepodites in the diet and the environment changed each year. Larvae fed mainly on abundant taxa in the environment, suggesting that larvae are opportunistic feeders. Nauplii and copepodites were abundant in the bay, especially in 1992. Copepodites were slightly more abundant in the diet of cod larvae in 1992 than in 1991, but this difference was smaller than in the environment. In addition, larvae with empty digestive tracts were scarce in 1991 and 1992. Prey concentrations in the bay in 1991 and 1992 seem to have been high enough to sustain most Pacific cod larvae.     

Protective effect of sodium glutamate and sorbitol on thermal denaturation of chicken and croaker actomyosin

The thermal protective effect (E‐Value) of sodium glutamate (Na‐Glu) on chicken and croaker actomyosin (AM) was significant but decreased slightly with increasing concentration. The E‐value of chicken AM with Na‐Glu was 1.11 mol/L^?1 at 0–0.75 mol/L and decreased to 0.4 mol/L^?1 at 0.75–1.5 mol/L. Likewise, the E‐value of croaker AM with Na‐Glu was 1.51 mol/L^?1 at 0–1 mol/L and decreased to 0.2 mol/L^?1 at 1–1.5 mol/L. Sorbitol showed a steady thermal protective effect on chicken and croaker AM. The E‐values of chicken and croaker AM at 0 to 1.5 mol/L sorbitol were 0.71 mol/L^?1 and 0.59 mol/L^?1, respectively. The protective effect of sorbitol on both types of AM was greater than that of Na‐Glu. Higher concentrations of Na‐Glu with chicken and croaker AM gave a decrease in viscosity number and turbidity. Higher concentrations of Na‐Glu caused internal aggregation of AM and the protective effect of Na‐Glu was decreased. The results of this experiment confirmed that Na‐Glu and sorbitol have different modes of action and ability to control the thermal denaturation of chicken and croaker AM.     

Antihypertensive effect of heshiko, a fermented mackerel product, on spontaneously hypertensive rats

ABSTRACT:   During the processing of heshiko , a fermented mackerel product, a rapid increase in peptide content in the extract and a remarkable decrease in the IC₅₀ (the inhibitor concentration to inhibit 50% of enzyme activity) as an index of the angiotensin I-converting enzyme (ACE) inhibitory activity were observed. Systolic blood pressure (SBP) in spontaneously hypertensive rats (SHR) decreased between 2 and 4 h after single oral administration of heshiko extract at a dose of 10 mg/kg as a peptide, and SBP recovered its initial level by 8 h. For single doses of extract at three different levels (5, 10 and 50 mg/kg), SBP similarly decreased after between 2 and 4 h. The decreased SBP at 50 mg/kg was almost equal to that at 10 mg/kg, indicating a low dose dependency for heshiko extract. Through successive administration of heshiko extract or its desalted extract at 10 mg/kg for 10 days, SBP decreased 7 days after the start of administration and it recovered its initial level 5 days after stopping administration. During these periods, the change in ACE activity in blood plasma from SHR administered the extract roughly corresponded to that of SBP, suggesting that ACE inhibition was related to a decrease in SBP. For long-term administration of the extract to 5-week-old SHR for 70 days, SBP decreased 28 days after the start of administration. The decreased SBP remained low for 28 days after stopping administration, whereas the decreased ACE activity recovered its initial level. These results suggest that heshiko extract influences not only ACE inhibition, but also other systems that regulate blood pressure.     

Shear tests of timber joints composed of sugi composite glulam beams using newly developed steel connectors

A research project supported by the Japan Wood Working Machinery Association has been conducted since 1999 to examine the feasibility of sugi (Cryptomeria japonica D. Don) composite glulam beams reinforced with Douglas fir (Pseudotsuga menziesii Franco) lamination. This study, part of the project, was concerned with the strength properties of timber joints composed of composite glulams using newly developed structural steel connectors. Two types of beam were prepared: 10 plies (inner 6 plies sugi, outer 4 plies Douglas fir) and 8 plies (inner 4 plies sugi, outer 4 plies Douglas fir). Two types of structural steel connector, Haratec and Standard, were used for joining the beam with a post or a girder. The relation between load and deformation of the joints was represented as a typical nonlinear curve. Initial stiffness and maximum load of the joint composed of the composite glulam were in the range between those of sugi and Douglas fir. Strength properties of the joints varied with three variables: type of connector, depth of the glulams, and the type of joint. Thus, the allowable loads for the connectors should be determined for each combination of these variables.     

Infection frequency of mature apple fruit with Erwinia amylovora deposited on pedicels and its survival in the fruit stored at low temperature

The infection frequency of mature apple fruit by Erwinia amylovora and the survival of E. amylovora in the fruit stored at low temperature were investigated. The fruit stems (pedicels) of 460 mature apple fruit were inoculated with 10⁵ or 10⁴ cfu of bioluminescent E. amylovora, tagged with lux genes. Nine days after inoculation, 43% and 27% of the fruit inoculated with 10⁵ and 10⁴ cfu, respectively, were infected. All infected fruit looked healthy. After 6 months of storage at 5°C, almost all of the 142 infected fruit had viable E. amylovora. Of the fruit containing E. amylovora internally, 19.5% had latent infections and the rest had blight symptoms. E. amylovora was not uniformly distributed in the fruit flesh, and internal brown lesions were observed where E. amylovora was densely distributed. These findings showed that mature apple fruit may be infected with E. amylovora, especially as latent infections, and act as a source for long-range dissemination.