Cold pre-treatment is effective for 1-MCP efficacy in ‘Tsugaru’ apple fruit

1-Methylcyclopropene (1-MCP) treatment maintains apple fruit quality during storage, but its efficacy is dependent on a number of conditions. ‘Tsugaru’ apples are a major early season cultivar in Japan, but because ‘Tsugaru’ fruit produce abundant ethylene, they have a short shelf-life, and efficacy of 1-MCP is not as high with ‘Tsugaru’ as with other cultivars. To improve 1-MCP efficacy, ‘Tsugaru’ fruit were pre-cooled at −1 °C or −3 °C for 24 h before 1-MCP treatment. Ethylene production decreased with the cold treatment, resulting in better storage after 1-MCP treatment. Although ethylene production was low at the end of 24 h of the cold pre-treatment, expression of ACS1, the ethylene receptor genes ERS1, ETR1(a), ETR1b, ETR2 and ETR5, and the cell wall degradation-related gene PG1 all increased with a 24 h cold treatment. It is assumed that these elevated gene expression levels were not caused by ethylene, but more directly by cold stimulus. Thus, a short period of cold stimulus suppresses ethylene production, but induces expression of some genes. 1-MCP treatment was more effective with some initial fruit chilling.     

The Effect of Parental Vitamin K Deficiency on Bone Structure in Mummichog Fundulus heteroclitus

The effect of parental vitamin K deficiency on developing bone structure was examined in mummichog ( Fundulus heteeroclitus ) larvae. Larvae from fish fed a vitamin K-deficient diet had abnormal vertebral formation, whereas larvae from fish fed a vitamin K-rich diet showed a significantly lower incidence of abnormality 5 d post-hatch. Larvae from fish that had been fed either the vitamin K-rich or the vitamin K-deficient diet had a high rate of abnormality when reared on a vitamin K-deficient diet for 30 d. Larvae from fish fed a vitamin K-rich diet that were reared on a vitamin K-rich diet showed a low rate of abnormality. Vertebral bone structure of larvae fed a vitamin K-deficient diet for 30 d was thin and rough, and seemed to have repaired fine fractures of the bone surface. In contrast, this type of structural abnormality was not observed in any larvae fed a vitamin K (phylloquinone) rich diet. These results imply that vitamin K deficiency causes the formation of thin and weak bone, and induces bone structure abnormality both in early development and during growth.     

Confirming the authenticity of the geographical origin of Naruto dried wakame Undaria pinnatifida using stable nitrogen isotope ratios

In aquatic ecosystems, the stable nitrogen isotope ratio (δ¹⁵N) of wakame is affected by the δ¹⁵N of its nitrogen source. Thus, the δ¹⁵N of wakame is thought to differ between those grown in different aquatic ecosystems. To confirm the authenticity of the geographic origin of Naruto dried wakame (DW), we conducted δ¹⁵N analysis. The δ¹⁵N (mean ± σ) of Naruto DW model samples (n = 72) was 11.1 ± 1.9 ‰. The δ¹⁵N confidence range of Naruto DW from the model was 5.3–16.9 ‰ (mean ± 3σ). The δ¹⁵N values of the DW model of Chinese (n = 23) and South Korean origin (n = 22) were 4.2 ± 1.4 and 1.6 ± 2.3 ‰, respectively. Within the δ¹⁵N confidence range of Naruto DW, two model samples of Chinese DW and one model sample of South Korean DW were found. From those results, DW of Naruto origin was able to be distinguished from DWs of the Chinese and the South Korean.     

Allele frequency distribution of the canine dopamine receptor D4 gene exon III and I in 23 breeds

Various canine breeds are remarkably different from each other not only in their sizes and shapes but also in behavioral traits, suggesting that some of them are under genetic control. Although dopaminergic neurotransmission system is considered to affect animal behavior, little is known about related genes in canine. Relations between specific alleles in polymorphic regions of the dopamine receptor D4 gene (DRD4) and personality or psychiatric disorders have been reported in humans, and we first found polymorphism in exon III region of the gene in 4 canine breeds. In this study we surveyed allele frequency distribution in 23 breeds including a total of 1,535 unrelated individuals. In exon III, 8 alleles including a novel allele were identified. A group of breeds in which the alleles 447b, 498 and 549 were frequent tended toward high scores in aggression-related behavioral traits than that with frequent alleles 435 and 447a. Moreover, a polymorphism based on 24 bp insertion/deletion was found in exon I region for the first time in dogs. This information may be of use for candidate gene studies of behavioral variation in dogs.     

Sequence analysis of VP2 gene of canine parvovirus isolated from domestic dogs in Japan in 1999 and 2000

Seven strains of canine parvovirus (CPV) were isolated from affected dogs in Japan between 1999 and 2000, and their VP2 genes were genetically analyzed. Comparison of the predicted amino acid sequences of VP2 suggested that three field isolates corresponded to CPV type 2a, while the other four to CPV type 2b. The phylogenetic tree constructed from the VP2 genes showed that the newly isolated strains are classified into the cluster consisting of recent Japanese and Taiwanese field isolates, which are distinct from Vietnamese isolates, United States Isolates, or classical CPV type 2. These results suggest that the CPV transmission occurred between Japan and Taiwan in 1990s, and the offspring are still circulating in both countries.     

Molecular sexing of Japanese cormorants used for traditional fishing on the Nagara River in Gifu City

The Japanese cormorants used in traditional fishing in Japan are wild derived and their sex cannot be determined from their appearance. Applicability of molecular sex determination based on the size difference between CHD1Z and CHD1W introns was confirmed in male and female Japanese cormorants whose sexes had been ascertained by pathological autopsy. All of 21 birds of unknown sex reared by a cormorant fishing master were identified as males. The molecular sexing method will provide valuable information on sex differences of wild Japanese cormorants, including tameness, trainability, behavior and fishing capability, as well as for future trials involving artificial reproduction.