Identification of ovalbumin phenotypes of the Asian indigenous chicken populations using polymerase chain reaction-restriction fragment length polymorphism

Three electrophoretic variations (AA, BB and AB) of ovalbumin controlled by codominant alleles Ov^A and Ov^B have been observed in various chicken populations. We compared nucleotide sequences of the open reading frame between two alleles of ovalbumin gene. The difference between the two alleles was found as a non‐synonymous substitution of asparagine to aspartic acid as a result of AAT to GAT point mutation at position 8032–8034 in exon 8. We developed polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) protocol in combination with Mbo I restriction endnuclease mapping for the detection of this substitution. By the PCR‐RFLP the allelic frequency of the Ov^B was estimated to be within the range of 0.000–0.150 in 11 Asian indigenous chicken populations and 0.000 in four improved breeds used in the present study. Gene frequency, estimated by PCR‐RFLP in the present study, paralleled that obtained by protein polymorphisms of egg white. Thus, this study provides, for the first time, information of the occurrence of ovalbumin allele Ov^A and Ov^B in Asian indigenous chicken populations.     

Development of Increased Oxolinic Acid-resistance in Burkholderia glumae

Genomic DNA, partially digested with Sau3AI, of Burkholderia glumae Pg-13, resistant to oxolinic acid (OA), was ligated into pUC118, and Escherichia coli DH5α resistant to 2.5 μg/ml OA was transformed with the plasmid. After incubation on a medium supplemented with 20 μg/ml OA, a clone harboring pB′46 was selected. The nucleotide sequence of the 724-bp insert of pB′46 had no homology to any characterized gene. B. glumae Pg-5, resistant to 10 μg/ ml OA, was transformed with plasmid pUCD3101B′46 containing the insert. An obtained transformant, B25, was resistant to 50 μg/ml OA and had greater resistance to other quinolones than did Pg-5. Transformants of OA-sensitive B. glumae with pUCD3101B′46 had OA sensitivity similar to that of the parental isolates. Received 18 September 2000/ Accepted in revised form 18 October 2000     

Mitochondrial diversity of native pigs in the mainland South and South-east Asian countries and its relationships between local wild boars

In this study, we analyzed DNA sequence of mitochondrial DNA (mtDNA) control regions on the 130 native domestic pigs and eight wild boars in the mainland South and South-east Asian countries including Bhutan, Cambodia, Laos, Myanmar, and Vietnam. Forty-four haplotypes were found in the 138 individuals, 41 were in the domestic and four were in wild boars. Only one haplotype was shared by domestic and wild population in Bhutan. In other cases, mtDNA of wild boars did not show close affinity to that of the domestic pigs in the same location, indicating that the native domestic pigs in these countries did not originate in the present habitat. Phylogenetic analyzes of mtDNA haplotypes recapitulated several major clusters identified in other studies, but 11 haplotypes were grouped in a new cluster we named MTSEA. In most cases, more than one lineage group were present in a sampling station, indicating that the present indigenous domestic pigs may have multiple origins. The MTSEA haplotypes were present in relatively high frequencies in domestic pigs in the mountainous area of mainland South-east Asia (Cambodia and Laos), with a few found in Myanmar and Bhutan. The distributions of MTSEA haplotypes are in great conformity with the distribution of present-day Mon-Khmer language and indicated the existence of yet another independent domestication. The D2 haplotypes that distribute high frequency (almost 100%) throughout the Chinese breeds were dominant in Bhutan, Myanmar, and Vietnam. These results suggest an existence of human-mediated dispersal of domestic pigs from north to the south during the historical expansion of Sino-Tibetan and Tai peoples. The D3 haplotypes previously reported in north India were found in sympatric domestic and wild pigs in Bhutan. The D3 haplotype is an important proof of independent domestication event and/or great gene flow between wild and domestic pigs in the foot of Himalaya.     

Urinary albumin and transferrin as early diagnostic markers of chronic kidney disease

Feline renal diseases are increasingly noted in veterinary practice. It is important to diagnose and identify the pathological basis of renal dysfunction accurately at an early stage, but there are only a few reports on this area in clinical veterinary medicine. We investigated the efficacy of measurement of urinary albumin (u-Alb) and urinary transferrin (u-Tf) for early diagnosis using 5-µl urine samples collected noninvasively by catheterization from normal (IRIS stage I) cats and cats with stage I chronic kidney disease (CKD). The u-Alb levels in normal and stage I CKD cats were 6.0 ± 4.5 and 11.2 ± 8.4 mg/dl, respectively, and the u-Tf levels were 0.09 ± 0.42 and 0.52 ± 0.79 mg/dl, respectively. Based on ROC curve analysis, the sensitivity and specificity of u-Alb and u-Tf were higher than those of the currently used biomarker, the plasma creatinine level. The sensitivity of u-Alb was higher than that of u-Tf, whereas the specificity of u-Tf was higher than that of u-Alb. The validity of the threshold albumin level (20 mg/dl) was confirmed by measurements using SDS-PAGE. Since leakage of u-Tf in urine precedes leakage of u-Alb, inclusion of u-Tf in biochemistry tests may be appropriate for IRIS staging as a diagnostic marker of early diagnosis of renal disorder in cats.     

Epidemiological study of Kabuto Mountain virus,a novel uukuvirus,in Japan

Kabuto Mountain virus (KAMV), the new member of the genus Uukuvirus, was isolated from the tick Haemaphysalis flava in 2018 in Japan. To date, there is no information on KAMV infection in human and animals. Therefore, serological surveillance of the infection among humans and wild mammals was conducted by virus-neutralization (VN) test and indirect immunofluorescence assay (IFA). Sera of 24 humans, 59 monkeys, 171 wild boars, 233 Sika deer, 7 bears, and 27 nutria in Yamaguchi Prefecture were analyzed by VN test. The positive ratio of humans, monkeys, wild boars, and Sika deer were 20.8%, 3.4%, 33.9% and 4.7%, respectively. No positive samples were detected in bears and nutria. The correlation coefficients between VN test and IFA in human, monkey, wild boar, and Sika deer sera were 0.5745, 0.7198, 0.9967 and 0.9525, respectively. In addition, KAMV was detected in one pool of Haemaphysalis formosensis ticks in Wakayama Prefecture. These results indicated that KAMV or KAMV-like virus is circulating among many wildlife and ticks, and that this virus incidentally infects humans.     

Effect of dietary fatty acid composition on the growth of the tiger puffer <Emphasis Type="Italic">Takifugu rubripes</Emphasis>

Effects of dietary fatty acid composition on the growth of the tiger puffer Takifugu rubripes were examined. Eight experimental diets were formulated with fish meal and casein as the major ingredients, providing 45.0–48.2% crude protein. Pollack and squid liver oils were used for the control diet while experimental diets contained three levels of EPA-DHA concentrated (C-HUFA) oils, soybean oil, linseed oil, and combinations of them, providing 0.5–5.5% n-3 HUFA and 5.0–11.1% crude lipid. Triplicate groups of fish with a mean body weight of 18.7 g per dietary treatment were fed the diets twice daily to apparent satiation, 6 days per week for 8 weeks. The final body weight and weight gain of the fish fed the soybean oil diet without C-HUFA oils were significantly lower than those fed the control diet. Both parameters were not statistically different among the other dietary groups, although the values obtained for the linseed oil diet without C-HUFA oils were lower. Similar trends were seen for SGR and feed efficiency. However, significantly lower PER values compared to the control were observed for the lower C-HUFA and the vegetable oil without C-HUFA oil groups. These results indicate that tiger puffer can be produced successfully with diets containing more than 1.5% n-3 HUFA.     

Polymorphisms in the bovine hemoglobin‐beta gene provide evidence for gene‐flow between wild species of Bos (Bibos) and domestic cattle in Southeast Asia

The electrophoretic variation in bovine hemoglobin‐beta (HBB) is one of the most investigated genetic markers. The presence of a unique HBB variant, HBB^X, in Southeast Asian cattle has been reputed as a sign of gene‐flow from wild bovine species. In this study, we analyzed the DNA sequences of HBB genes in domestic and wild bovine species to verify this belief. Isoelectric focusing of HBB chain revealed that the HBB^X in domestic cattle had dimorphism and was separated into HBB^X1 and HBB^X2. The HBB^X1 had the same DNA sequence of the common HBB variant in gayal (Bos gaurus frontalis), while some of the HBB^X2 were identical with that of Cambodian banteng (Bos javanicus birmanicus). As a result, we confirmed that the bovine HBB variants can be a good indicator of introgression between wild and domestic cattle. The HBB^X1 was always predominant to HBB^X2 in the continental populations, suggesting that the gaur had contributed to the gene pool of domestic cattle in this region much more than the banteng. On the other hand, the mitochondrial DNA analysis could not detect gene‐flow from wild species. Autosomal markers that can trace the phylogeny between alleles are suitable for the assessment of bovine interspecific introgression.     

Regulation of granulosa cell apoptosis by death ligand–receptor signaling

Several hundred thousand primordial follicles are present in the mammalian ovary, however, only 1% develop to the preovulatory stage and finally ovulate. The remainder will be eliminated via a degenerative process called ‘atresia’. The endocrinological regulatory mechanisms involved in follicular development and atresia have largely been characterized but the precise temporal and molecular mechanisms involved in the regulation of these events remain unknown. Many recent studies suggest that apoptosis in ovarian granulosa cells plays a crucial role in follicular atresia. Notably, death ligand‐receptor interaction and subsequent intracellular signaling have been demonstrated to be the key mechanisms regulating granulosa cell apoptosis. In this review we provide an overview of granulosa cell apoptosis regulated by death ligand‐receptor signaling. The roles of death ligands and receptors [Fas ligand (FasL)]‐Fas, tumor necrosis factor α (TNFα)‐TNF receptor and TNFα‐related apoptosis‐inducing ligand (TRAIL)‐TRAIL receptor (TRAILR)] and intracellular death‐signal mediating molecules (Fas‐associated death domain protein), TNF receptor 1‐associated death domain protein, caspases, apoptotic protease‐activating factor 1, TNFR‐associated factor 2 and cellular FLICE‐like inhibitory protein in granulosa cells are discussed.