Single oral β-cryptoxanthin administration increases its serum concentration and enhances peripheral blood neutrophil function in Holstein cattle

We investigated the effect of oral administration of β-cryptoxanthin (β-CRX) on its serum concentration and peripheral neutrophil functions by the chemiluminescence (CL) response in Holstein cattle. A single oral administration of β-CRX was performed for serum β-CRX concentration (0, 0.05, 0.1, or 0.2 mg/kg body weight [BW]) and for peak CL response of peripheral neutrophils (0.2 mg/kg BW). The serum β-CRX concentration was peaked on 2 days after, similar to peak CL response on 3 days after β-CRX administration. Therefore, a single oral administration of β-CRX (0.2 mg/kg BW) induces higher serum concentration and concurrently enhances bactericidal ability of peripheral neutrophils in Holstein cattle.     

Trophinin is expressed in the porcine endometrium during the estrous cycle

We investigated endometrial expression of trophinin mRNA and protein, homophilic cell adhesion molecules, during the estrous cycle of gilts. An immunopositive reaction for trophinin was observed in the luminal and glandular epithelia of the endometrium at all stages of the estrous cycle, but not in endometrial stromal cells or the myometrium. A partial coding sequence of porcine trophinin was similar to sequences in humans and mice, with homologies of 75% and 70%, respectively. As in humans and mice, the trophinin gene is expressed in the endometrium. Trophinin, however, is expressed in the endometrium of the pig throughout the estrous cycle, higher expression levels were observed at some points of the luteal phase, as in humans. These findings suggest that regulation of trophinin gene expression in the pig is different from that in mice, but similar to that in humans. Furthermore, the present results suggest that the pig might be a suitable model for studying the physiological importance of trophinin in early pregnancy in humans.     

Distribution of mecA-harboring staphylococci in healthy mares

The prevalence of staphylococci that harbor the mecA gene responsible for methicillin resistance was examined in healthy breeding mares. Staphylococci often cause diseases of horses such as metritis, keratitis, and abscess. Methicillin-resistant staphylococci would make antibiotic treatments ineffective, so it may be significant to know the distribution of mecA-harboring staphylococci in mares. Isolation of mecA-harboring staphylococci was achieved from nares and pasterns of 100 mares in Hokkaido, Japan. From 13% of the mares, mecA-harboring staphylococci, including 15 isolates of Staphylococcus sciuri and 3 of Staphylococcus lentus, were isolated. Isolates of S. sciuri were found to be genetically polyclonal by pulsed-field gel electrophoresis. These isolates produced no PCase and showed low or no resistance to beta-lactam and other classes of antibiotics. Distribution of staphylococcal species and levels of antibiotic resistance were found to be different between isolates from the present mares and those previously reported from riding-horses. Antibiotic pressure may lead to these differences. In addition, it appears that mecA-harboring S. sciuri may be native to horses.     

Development and evaluation of a model for prediction of fecal and urinary nitrogen excretions in cattle

The reduction of nitrogen (N) excretion in animal production is crucial in intensive farming systems particularly in the developed countries. In this study, a model to predict N excretion in cattle was developed based on existing feeding standards and evaluated using independent N balance experiments for Holstein steers and lactating cows and Japanese Black (JB) steers. Although model predictions for fecal and urinary N excretions appeared to be close to observed values in plot figures, statistical analysis showed that the model tended to over-predict both fecal and urinary N excretions, especially in Holstein lactating cows. This was because body weight changes of cows during lactation period were not considered in the model due to the lack of information (i.e., body weight gain or loss) available in the experimental data for evaluation. There were large mean bias and small line bias for urinary N prediction, but reverse results were obtained for fecal N prediction. The largest mean square prediction errors for both N excretions were due to random variation in all cases. When all data were pooled (combined), the accuracy for predictions for fecal N excretion was considerably high (r² = 0.94), indicating that the model may predict fecal N excretion beyond breeds, sexes and physiological states (growing and lactating). More information and accumulated data will be required to predict urinary N excretion under a wide range of genotype and environmental situation.     

Defense Mechanism of Rice Plant to Respiratory Inhibition by a Promising Candidate Blasticide, SSF126

A new candidate systemic rice blasticide, SSF126, dose-dependently inhibited NADH oxidation by submitochondrial particles from rice roots. However, oxidation by the root submitochondrial particles was much less susceptible to SSF126 compared to that by submitochondrial particles from mycelial cells ofPyricularia grisea, a pathogen causing rice blast. Interestingly, SSF126 did not completely suppress the respiration by intact rice roots, and the respiratory activity of the roots recovered from inhibition time-dependently even in the presence of SSF126 at concentrations sufficient to fully block oxidation by the submitochondrial particles. This recovery was not due to selective extrusion of SSF126 from the roots, but to switching from the cytochrome pathway to the alternative cyanide-resistant respiratory pathway. In immunoblots of the alternative oxidase, high molecular mass species were detected in the mitochondria from rice roots in addition to low molecular mass species. Quantification of high and low molecular mass species revealed an increase in the amount of a protein corresponding to a 36-kDa species equivalent to a decrease in the amount of a protein corresponding to a 72-kDa species following a 5-h incubation with SSF126. This conversion of the alternative oxidase to the low molecular mass species in the mitochondria was correlated with the respiratory recovery found in intact rice roots, suggesting that the low molecular mass species is the active form of the alternative oxidase and the high molecular mass species is the inactive form. These results suggest that rice plants can block the severe injury caused by limiting the cytochrome pathway by SSF126 through utilization of the alternative pathway promoted by the interconversion of the alternative oxidase protein.     

Biotin Induces Sporulation of Mulberry Anthracnose Fungus, Colletotrichum dematium

Compounds in mulberry leaves inducing sporulation of C. dematium, mulberry anthracnose fungus, were detected. Dissolved or suspended aqueous solutions (1%) of 16 amino acids and 10 vitamins occurring in mulberry leaves were applied individually at the margin of the fungal colony growing on PSA plate. Sporulation was induced only where a biotin solution was applied on the mycelium at a concentration of at least 0.01 ppm. This result suggests that biotin, which occurs in mulberry leaves (ca. 0.6 mg/kg of dried leaves), has a role in inducing sporulation of C. dematium. Received 20 August 1999/ Accepted in revised form 16 November 1999     

Fine mapping of quantitative trait loci affecting organ weights by mouse intersubspecific subcongenic strain analysis

The genetic architecture of organ weights is not well understood. In this study, we fine‐mapped quantitative trait loci (QTLs) affecting organ weights by characterizing six intersubspecific subcongenic mouse strains with overlapping and non‐overlapping genomic regions on chromosome 2 derived from wild Mus musculus castaneus. QTLs for heart, lung, spleen and kidney weights were revealed on a 6.38‐Mb genomic region between two microsatellite markers, D2Mit323 and D2Mit472. Effects of the castaneus alleles at the organ weight QTLs were all opposite in direction to a body weight QTL previously mapped to the same genomic region. In addition, new QTLs for lung and kidney weights were revealed on a different 3.57‐Mb region between D2Mit205 and D2Mit182. Their effects were dependent on that of another body weight QTL previously mapped to that genomic region. The organ weight QTLs revealed were all duplicated in independent analyses with F₂ intercross populations between subcongenic strains carrying these QTLs and their background strain. The findings suggested that organ weights are not exclusively regulated by genetic loci that commonly influence overall body weight and rather that there are loci contributing to the growth of specific organs only.     

Identification of CpG oligodeoxynucleotide sequences that induce IFN-gamma production in canine peripheral blood mononuclear cells

Oligodeoxynucleotides containing the cytosine-phosphate-guanine (CpG) motif (CpG-ODNs) have been shown to induce T(H)1 immune responses in animals. Since the sequences of CpG-ODNs that induce T(H)1 responses are considered to vary among animal species, it is necessary to identify effective CpG-ODNs in each animal. In order to identify the sequences of CpG-ODNs that induce T(H)1 responses in dogs, mRNA expression and protein production of IFN-gamma were examined in peripheral blood mononuclear cells (PBMCs) from healthy dogs treated with 11 kinds of synthetic CpG-ODNs. One of the 11 CpG-ODNs (No. 2 CpG-ODN, 5'-GGTGCATCGATGCAGGGGGG-3') was shown to significantly increase mRNA expression and protein production of IFN-gamma in canine PBMCs in a manner dependent on the sequence of the CpG motif. This CpG-ODN also enhanced the expression of IL-12 p40 mRNA in canine PBMCs, whereas expression of IL-12 p35, IL-18, and IL-4 mRNAs was not induced by this CpG-ODN. These results indicate that this CpG-ODN was able to produce IFN-gamma by induction of T(H)1-skewed immune response in dogs. CpG-ODNs may be useful for inducing prophylactic and therapeutic immunity against allergic diseases, viral infection, and tumors in dogs.