The effects of inclusion levels of urea-treated potato pulp silage in concentrate and roughage sources on finishing performance and carcass quality in cull beef cows

An experiment was conducted to determine the effects of inclusion levels of potato pulp silage in concentrate (0, 15, 30 or 45%; on a dry matter basis) and roughage sources (rice straw or wheat straw) on finishing performance and carcass quality of cull beef cows. Sixteen Japanese Black (Wagyu) mature cull cows (490 ± 31 kg of BW) were used in this experiment. Increasing the levels of potato pulp silage in concentrate and roughage sources did not significantly affect feed intake in cows. In addition, the final body weight, daily gain and feed : gain ratio were not influenced by the inclusion levels of potato pulp silage in concentrate and the type of roughage. Increasing the inclusion levels of potato pulp silage in concentrate would probably decrease the marbling score. The L* values of the longissimus muscle (LM) tended to respond quadratically ( P  = 0.078) as the inclusion levels of potato pulp silage in concentrate increased, and was lowest for cows fed the concentrate which included 30% potato pulp silage. The a* and b* values of the LM and fat color were not affected by the inclusion levels of potato pulp silage in concentrate. No effects of roughage sources on finishing performance were observed.     

Response of riparian vegetation to the removal of the invasive forb,Solidago gigantea,and its litter layer

In order to explore the methods of recovering native grasses into exotic vegetation, the response of riparian vegetation to the removal of the above‐ground shoots and/or litter of Solidago gigantea in a flood plain in Hokkaido, northern Japan, was investigated. The four treatments were: the removal of the above‐ground shoots of S. gigantea (A); the removal of the litter of S. gigantea (L); the removal of both the above‐ground shoots and litter of S. gigantea (AL); and a control (C). The vegetation cover and S. gigantea cover decreased in the A and AL treatments and increased in the L and C treatments. The understory plant cover increased in the A and AL treatments, but did not change in the L and C treatments. The increases in the understory cover in the A and AL treatments were associated with increases in Phalaris arundinacea. The seedling emergence of P. arundinacea was promoted by AL. In a greenhouse, the S. gigantea litter tended to decrease the seed germination of P. arundinacea. The AL treatment also increased the abundance of the other exotic plant, Solidago altissima. The continuous removal of the above‐ground shoots and litter of S. gigantea long term is effective for promoting the recovery and emergence of native riparian grassland vegetation. However, this method also promotes the recovery of other exotics.     

Localization of interleukin-6 receptor mRNA in the pregnant and non-pregnant mouse uterus

To understand roles of interleukin 6 (IL-6) family cytokines for pregnancy in mice, localization of IL-6 receptor (IL-6R) mRNA was investigated in non- and early pregnant uteri by in situ hybridization. IL-6R mRNA was expressed in all non-pregnant uteri and in pregnant uteri from the third day (Day 3) to the sixth day of pregnancy (Day 6; the day of plug = Day 1). IL-6R mRNA signals were detected in non-pregnant mice in the luminal and glandular epithelium. Signal strength varied according to the sexual cycle. There was no correlation between the signal strength of the IL-6R mRNA and the serum concentrations of progesterone and 17beta-estradiol, which show a monophasic rise in the non-pregnant sexual cycle. In pregnant mice, slight signals were detectable in the luminal and glandular epithelium on Day 3. IL-6R mRNA messages increased with progression towards Day 4, however, localization changed drastically on Day 5. Stromal cells abruptly expressed their mRNA on Day 5, and these cells strongly expressed it on Day 6. The function of IL-6R in the luminal and glandular epithelium might be different from that in the stroma during the implantation period. In addition, few signals were identified in the stromal cells adjacent to the luminal epithelium on Day 6. This suggests that there are two types of stromal cells on Day 6 in mice.     

Fetal heart rate monitoring from maternal body surface potentials using independent component analysis

The fetal heart rate is indispensable for monitoring the health of unborn cattle fetuses. To monitor the fetal heart rate, a method employing independent component analysis (ICA) to extract the fetal electrocardiogram (fECG) from potentials measured on the maternal body surface and composed of a mixture of the maternal ECG (mECG), fECG, baseline drift and noise is described. A mixing of the raw data was simplified using a linear time‐invariant model. To separate the fECG from the mECG, baseline drift, and noise, an ICA strategy was applied, using a hyperbolic tangent as the contrast function and treating mutual information with the minimization principle to find the optimum demixing matrix to derive the fECG from the measured signals. After the feasibility of this method was shown on simulated signals obtained by randomly mixing pure fECG, pure mECG, low frequency sinusoidal drift and noise, real signals from three cloned pregnant Holstein cows with 157, 177 and 224‐day gestation periods were used to verify the separation method. The results show that the fECG, mECG, low‐frequency sinusoidal drift and noise can be clearly segregated in simulations, and that the fECG, mECG, baseline drift and noise can be successfully derived from real signals. The ICA approach has great potential in effectively detecting the fECG from maternal body surface potentials.     

Equine coronavirus induces apoptosis in cultured cells

Equine coronavirus (ECoV) was first isolated from a diarrheic foal and was found genetically similar to group II coronaviruses. However, its pathological characteristics were not adequately investigated. In our preliminary in vitro investigation, ECoV-induced cell death was observed in bovine kidney-derived MDBK cells. Based on this finding, we investigated whether the ECoV-induced CPE was apoptosis. Following ECoV infection, MDBK cells showed morphological changes such as cell rounding and detachment from the culture surface. Moreover, syncytium formation was observed as the other type of cytopathic effect in ECoV infection. Morphologic and biochemical features of apoptosis, such as nuclear fragmentation and DNA ladder formation, were also detected in ECoV-infected cells. Moreover, as is commonly observed in coronavirus infection in other animals, the activities of effecter caspases – caspase-3/7 – and initiator caspases – caspase-8 and caspase-9 – that are representative factors in the death receptor-mediated apoptotic pathway and mitochondrial apoptotic pathway, respectively, were increased in ECoV-infected MDBK cells. Therefore, it was suggested that ECoV can induce apoptosis in MDBK cells via a caspase-dependent pathway. Apoptotic death of infected cells is detrimental because it causes cell and tissue destruction and inflammatory responses. Although the pathological characteristics of ECoV are largely unknown, apoptosis may be the pathological basis of lesions of the digestive system in ECoV infection.     

Effects of acidity and a metabolic inhibitor on incorporation of calcium and inorganic carbon into endolymph and otoliths in salmon Oncorhynchus masou

ABSTRACT:   To investigate the mechanisms of calcium carbonate formation of teleost otoliths, using the double labeling technique of ⁴⁵Ca²⁺ and H¹⁴CO₃^–, the effects of tissue elimination, a metabolic inhibitor (cyanide) and acidity on the incorporation of calcium and inorganic carbon into endolymph and otoliths were examined. Incorporation of calcium and inorganic carbon into otoliths was decreased to 36% and 45%, respectively, by removing the sacculus. In contrast, cyanide inhibited incorporation of inorganic carbon and calcium into endolymph and otoliths in a concentration-dependent manner. Acidity in the incubation medium decreased the accumulation of inorganic carbon within the endolymph and otoliths. Calcium incorporation was not affected by variation of pH in the medium. These results indicate that calcium and bicarbonate are actively transported to endolymph via the sacculus, and it is suggested that the transport is involved in the oversaturation state for calcium carbonate in the endolymph and regulates subsequent calcification of otoliths.     

Genetic and serological characterization of novel serotype G8 bovine group A rotavirus strains isolated in Japan

G8 bovine group A rotaviruses isolated in Japan were genetically and serologically characterized. The VP7 gene nucleotide and amino acid sequences revealed high identity with each other. All Japanese G8 strains were classified into the same lineage in the phylogenetic analysis based on VP7 gene sequences. Antisera to four Japanese G8 strains neutralized other G8 strains, but their neutralizing titers were between 8-fold lower and 2-fold higher than homologous strains. These results suggest that the VP7s of Japanese G8 strains have similar genetic and serologic characteristics. Observed differences in the neutralizing abilities of antisera for each strain appear to depend on differences in the P serotypes/genotypes.     

IGF-I Overexpression causes fetal loss during placentation in mice

To understand the role of IGF-I in murine pregnancy, we studied the reproductive performance of IGF-I overexpressed mice. Fetal loss occurred only in the transfected uterine horn during day 10-15 of pregnancy. The placenta appeared healthy until Day 10 of pregnancy. From day 12, the decidua basalis of the transfected horn increased in thickness. The vascular lumen was expanded, and most of embryos were dead. Uterine natural killer cells did not undergo apoptosis from day 10 to day 15 when they usually go through apoptosis. Thus, it is likely that IGF-I plays a role in the decidual formation through regulation of uNK cells. This is the first report to demonstrate that IGF-I overexpression can cause fetal loss during murine placentation.     

Changes in developmental duration of direct-seeded rice in a well-drained paddy field in response to late planting

We investigated changes in the developmental duration of rice cultivars with a wide range of maturities in response to late planting. Elucidating the relationship between cropping season and the progress of growth stages is important for establishing direct-seeded cultivation and creating growth models. Late planting of the intermediate to late maturing cultivars Akidawara and Hoshijirushi decreased the time from emergence to panicle formation and decreased the cumulative effective temperature (CET) and cumulative effective soil temperature (CEST). In the very early maturing cultivars Ichibanboshi and Fusakogane, the changes in number of days, CET, and CEST from emergence to panicle formation with late planting were small. From emergence to heading and maturity, the number of days, CET, and CEST of many cultivars tended to increase until mid-May and then decreased. The changes in the number of days, CET, and CEST caused by late planting were greater for the intermediate to late maturing cultivars than for the very early maturing cultivars. The differences between cultivars were greatest with early May sowing, and then decreased with later planting. Short-day condition revealed significant differences in the duration of vegetative growth and CET among cultivars, but long-day condition erased these differences. These results demonstrate that the photosensitivity and thermosensitivity of cultivars are especially important in crop planning and for creating growth models of direct-seeded rice.