KAv-1 is Better Suited to Chick Fibroblast Culture than DMEM or 199 Media

Cultured cells are a useful resource for poultry scientists, since these cells allow scientists to evaluate biological responses to conditions such as infectious diseases in vitro while mimicking the whole-body response in birds. However avian cell culture requires an optimized basal medium, and there are currently relatively few options for this basal medium (medium 199 and KAv-1). This means that there is still room for the development of an optimal basal medium for avian cell culture. Here we compare KAv-1 medium, Dulbecco''s modified Eagle medium (DMEM) and medium 199 during the culture of chick fibroblasts and determine that KAv-1 remains the optimal medium for these assays. Our results show that DNA damage is reduced in fibroblasts cultured in the KAv-1 medium, when compared to both DMEM and Medium 199 and that these cells also display improved growth dynamics in KAv-1 medium when compared to both DMEM and medium 199. To the best of our knowledge, this is the first study to describe a comparative analysis of culture media for avian cells, which would provide useful information for poultry scientists.     

Purification and sensitivity of Clostridium chauvoei hemolysin to various erythrocytes

Using ammonium sulphate fractionation, the Clostridium chauvoei hemolysin was purified by cation exchange chromatography and sephacryl S-100 gel filtration. The molecular mass of the hemolysin, determined by SDS-PAGE was found to be approximately 27kDa. The activity of the hemolysin was determined in erythrocytes of various animals, with sensitivities observed in the order of cow, sheep, chicken, rabbit, rat, mouse, dog and horse. Temperature affected the sensitivity of erythrocytes to C. chauvoei hemolysin. These results may reflect distinct characteristics of the hemolytic activity of C. chauvoei hemolysin and that the hemolysin may be pore-forming.     

Origin and thermodynamic properties of the instability of synthetic azo colorants in gum arabic solutions

The instability of some industrially important synthetic azo colorants, including sunset yellow, azorubine, and allura red, toward gum arabic in aqueous solution has been a long-standing problem for the beverage and confectionery industries. Precipitation of these colorants causes the deterioration of product appearance and properties. This work examines the origin and nature of the problem by analysis of the precipitate and thermodynamic studies of gum arabic-colorant interactions using isothermal titration calorimetry (ITC). The presence of divalent alkaline earth metals in gum arabic samples, that is, calcium and magnesium, is shown to be responsible for the precipitation of the azo colorants. There is no direct interaction between gum arabic and the colorant molecules, and the precipitate is formed likely due to the mediation/bridging by the divalent cations. The thermodynamic knowledge gained from the ITC studies, for example, binding affinity, stoichiometry, and enthalpy, enables interpretation of many industrial observations.     

DNA marker for resistance to Puccinia horiana in chrysanthemum (Chrysanthemum morifolium Ramat.) “Southern Pegasus”

White rust caused by Puccinia horiana Henn. adversely affects chrysanthemum (Chrysanthemum morifolium Ramat.) production. The breeding of resistant varieties is effective in controlling the disease. Here we aimed to develop DNA markers for the strong resistance to P. horiana. We conducted a linkage analysis based on the genome-wide association study (GWAS) method. We employed a biparental population for the GWAS, wherein the single nucleotide polymorphism (SNP) allele frequency could be predicted. The population was derived from crosses between a strong resistant “Southern Pegasus” and a susceptible line. The GWAS used simplex and double-simplex SNP markers selected out of SNP candidates mined from ddRAD-Seq data of an F₁ biparental population. These F₁ individuals segregated in a 1:1 ratio of resistant to susceptible. Twenty-one simplex SNPs were significantly associated with P. horiana resistance in “Southern Pegasus” and generated one linkage group. These results show the presence of a single resistance gene in “Southern Pegasus”. We identified the nearest SNP marker located 2.2 cM from P. horiana resistance locus and demonstrated this SNP marker-resistance link using an independent population. This is the first report of an effective DNA marker linked to a gene for P. horiana resistance in chrysanthemum.     

Interaction of orexin/hypocretin-like immunoreactive neurons with melanin-concentrating hormone and α-melanocyte-stimulating hormone neurons in brain of a pleuronectiform fish, barfin flounder

Immunohistochemical localization of orexin/hypocretin in the brain of a pleuronectiform fish, the barfin flounder Verasper moseri was examined as the first step in unraveling the possible function of the hormone in the brain. Orexin-A-like immunoreactive (ir) cell bodies were found to be located in the nucleus posterioris periventricularis (NPPv) of the hypothalamus, and orexin-A-like-ir fibers were detected not only in the hypothalamus but also extensively throughout the brain. The orexin-A-like-ir cell bodies did not project their fibers to the pituitary gland. Since melaninconcentrating hormone (MCH) and α-melanocyte-stimulating hormone (α-MSH) are suggested to regulate food intake in addition to orexin/hypocretin in the teleost fish, it was examined whether neural connections exist between orexin neurons and the MCH and α-MSH neurons in the barfin flounder brain by using double-staining immunohistochemistry. Some orexin-A-like-ir fibers were in close contact with the MCH-ir and α-MSH-ir cell bodies in the hypothalamus. Moreover, a few MCH-ir and α-MSH-ir fibers were in close contact with the orexin-A-like-ir cell bodies in the hypothalamus. These results suggest that reciprocal connections exist between the orexin and MCH neurons and between the orexin and α-MSH neurons in the brain of the barfin flounder.     

Effects of structure on radical-scavenging abilities and antioxidative activities of tea polyphenols: NMR analytical approach using 1,1-diphenyl-2-picrylhydrazyl radicals

Tea (Camellia sinensis) leaves contain various antioxidants such as ascorbic acid (1) and polyphenols. This study tries to clarify the molecular mechanisms underlying the antioxidative and radical-scavenging activities of these antioxidants, and the reactivities of each antioxidant have been compared against that of the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH, 2) using nuclear magnetic resonance (NMR) analysis. Catechol (3) and (+)-taxifolin (4) were oxidized to o-quinone by 2. However, ethyl protocatechuate (5) and quercetin (6) were not oxidized to o-quinone, even though they possess a catechol structure. The radical-scavenging ability of o-dihydroxyl phenolic compounds with a conjugated olefinic double bond (e.g., 6) was superior to that of compounds without this bond (e.g., 4), whereas the ability of o-dihydroxyl phenolic compounds possessing a conjugated carbonyl bond (5) was inferior to that of compounds lacking this bond (3). Vicinal trihydroxyl phenolic compounds with a conjugated olefinic double bond [e.g., myricetin (7)] had an inferior scavenging ability as compared with compounds lacking this bond [e.g., pyrogallol (8)], but 7 was a better scavenger than compounds with a conjugated carbonyl double bond [e.g., ethyl gallate (9)]. In addition, vicinal trihydroxyl phenolic compounds (e.g., 9) were superior to o-dihydroxyl phenolic compounds (e.g., 6). Finally, 1 scavenged radicals more quickly than 8.     

Cleaning procedures and cleanliness assessments of bucket milkers and suckling buckets on Japanese dairy farms

Cleanliness of milking equipment is known to be important for the safety of dairy products and to prevent the spread of diseases among cows. We investigated the cleaning procedures of milking equipment and suckling equipment on Japanese dairy farms, and the cleanliness of bucket milkers, suckling buckets, milk receivers, and bulk tanks, using adenosine triphosphate (ATP) bioluminescence test. Bulk tanks (except one bulk tank) and milk receivers were washed by automated cleaning, but all bucket milkers and suckling buckets were washed by manual cleaning. Detergents were often not used to clean bucket milkers and suckling buckets. The log₁₀ transformed relative luminescence units (LRLU) of equipment washed by manual cleaning was higher than equipment washed by automated cleaning. Clean surfaces (≤2.2 LRLU) were only observed on the bulk tank and the milk receiver. More than 50% of the LRLU of the mouthpiece, the rubber packing of claw, and the nipple of the suckling bucket were determined dirty. These results suggest that the cleanliness of the bucket milkers and the suckling buckets washed by manual cleaning was lower than that of the equipment washed by automated cleaning, and may be due to insufficient cleaning procedures.