Prevalence of canine coronavirus (CCoV) in dog in Japan: detection of CCoV RNA and retrospective serological analysis

We collected rectal swabs from dogs in Japan during 2011 to 2014, and canine coronavirus (CCoV) nucleocapsid gene was detected by RT-PCR. The relationship between CCoV infection and the manifestation of diarrhea symptoms was investigated, and a correlation was noted (df=1, χ²=8.90, P<0.005). The types of CCoV detected in samples from CCoV-infected dogs were CCoV-I in 88.9% and CCoV-II in 7.4%, respectively. We retrospectively investigated the seroprevalence of CCoV-I in dogs in Japan during 1998 to 2006. The sera were tested with a neutralizing antibody test. In the absence of CCoV-I laboratory strain, we used feline coronavirus (FCoV)-I that shares high sequence homology in the S protein with CCoV-I. 77.7% of the sera were positive for neutralizing anti-FCoV-I antibodies.     

The formation process of button ulcers in pigs experimentally infected with a subgenotype 2.1 isolate of classical swine fever virus

We evaluated the role of classical swine fever virus (CSFV) in the formation of button ulcers in the mucosa of the gastrointestinal tract. Histopathological and immunohistochemical analyses of pigs experimentally infected with a subgenotype 2.1 isolate of CSFV, which was isolated in Japan in 2019, revealed follicular necrosis in the submucosal mucosa-associated lymphoid tissue and herniation of crypts as factors that contribute to the development of button ulcers during CSFV infection. These findings indicate that CSFV induces follicular necrosis and is one of the causative agents of button ulcers in pigs.     

日本湖泊地区水质保护对策与成效

日本自60年代后期,随着工农业发展和人口增加,在水资源丰富的湖泊周边地区由于污染物的过量排放导致湖泊水体污染。日本环境省为了保护湖泊水质,制定了“湖泊水质保护特别措施法”。同时,农林水产省在湖泊地区相继制定了“农业环境规范”、“可持续农业生产方式”、“农田、水体、环保对策”等一系列环境友好型农业综合生产技术措施,促进湖泊地区水质保护和该地区农业可持续发展。围绕日本两大代表性湖泊琵琶湖和霞浦湖,介绍了日本湖泊地区水质保护综合对策的形成、成效及其发展,以及在此基础上环保型农业政策体系的提出、发展和实施效果,以及环保型农业政策指导下的湖泊保护对策及目标等;并指出了日本环保型农业存在的问题,以期为我国探索农业可持续发展之路提供更多的启示。     

Development of a culture protocol for Rhodomonas sp. Hf-1 strain through laboratory trials

Fisheries Science - Rhodomonas sp. Hf-1 is a marine microalgal strain with a high nutritional value. In order to produce this microalga effectively and inexpensively in a hatchery, its production...     

Studies on the inhibition of methanogenesis and dechlorination by (4-hydroxyphenyl) chloromethanesulfonate

The purpose of this study was to demonstrate the inhibitory effect of chemicals on methane emissions in paddy soil. We found that (4-hydroxyphenyl) chloromethanesulfonate (C-1) has a methanogenic inhibition activity, and we studied its inhibition mechanism using laboratory tests. The study found that C-1 treatment of flooded soil did not significantly affect the bacterial community but rather the archaeal community; particularly, Methanosarcina spp. C-1 strongly inhibited the aceticlastic methanogenesis route. It was suggested that the inhibitory target of C-1 was different from the well-known methanogenic inhibitor 2-bromoethanesulfonate, which targets methyl-coenzyme M reductase of methanogen. In addition, C-1 had a secondary effect of inhibiting the dechlorination of chlorophenols. Although field trials are required as the next development step, C-1 can be used to reduce methane emissions from paddy fields, one of the largest sources in the agricultural sector.     

Regulation of secondary follicle growth by theca cells and insulin-like growth factor 1

Ovaries contain follicles at various stages of development, including primordial, primary, secondary, antral and Graafian follicles. Although the growth of these follicles is controlled to maintain regular ovulation, the mechanism through which this occurs remains unclear. In our study, we found that the growth rate of cultured secondary follicles separated from mice ovaries differed between follicles. After 4 days of culture, the size of some secondary follicles was markedly increased, while that of others had either slightly increased, remained unchanged or shrunk. We compared the expression levels of growth factors between these secondary follicles and found that the growth rate of cultured secondary follicles correlated with the expression level of insulin-like growth factor 1 (Igf1) mRNA. Igf1 mRNA expression level in secondary follicles containing theca cells was higher than that in secondary follicles without theca cells, and the granulosa cell proliferation around follicles containing theca cells was increased. Furthermore, an IGF1 inhibitor also inhibited the granulosa cell proliferation, and administration of IGF1 to secondary follicles without growth promoted granulosa cell proliferation. These results indicated that the theca cells of secondary follicles induced the expression of IGF1 and promoted the follicle growth.     

Effect of supplementation with the reduced form of coenzyme Q10 on semen quality and antioxidant status in dogs with poor semen quality: Three case studies

Oxidative stress owing to an imbalance between reactive oxygen species and antioxidants, such as coenzyme Q10 (CoQ10), is a major contributor to male infertility. We investigated the effects of the reduced form of CoQ10 (ubiquinol) supplementation on semen quality in dogs with poor semen quality. Three dogs received 100 mg of ubiquinol orally once daily for 12 weeks. Semen quality, serum testosterone, and seminal plasma superoxide dismutase (SOD) activity were examined at 2-week intervals from 2 weeks before ubiquinol supplementation to 4 weeks after the treatment. Ubiquinol improved sperm motility, reduced morphologically abnormal sperm, and increased seminal plasma SOD activity; however, it had no effect on testosterone level, semen volume, and sperm number. Ubiquinol supplementation could be used as a non-endocrine therapy for infertile dogs.     

Effect of protein hydrolysate from Antarctic krill meat on the state of water and denaturation by dehydration of lizard fish myofibrils

ABSTRACT: To utilize Antarctic krill as functional food, protein hydrolysates were prepared by enzymatic hydrolysis. Their effects on the state of water in myofibrils of lizard fish and dehydration-induced denaturation were compared with those from two species of shrimp, glucose, and sodium glutamate. Peptides are major components in hydrolysates, occupying approximately 85–93% of the total materials. The Antarctic krill protein hydrolysates stabilized the bonding of water molecules, leading to suppressed denaturation of myofibrils during the dehydration process. Similar effects were observed for shrimp protein hydrolysates. The effect of the hydrolysate was less than that by glucose and sodium glutamate.