Laterality of spinocerebellar neurons in the chicken spinal cord

The aim in this study is to elucidate the laterality of chicken spinocerebellar (SC) neurons that originate from the caudal cervical to caudal lumbosacral spinal cord. SC neurons in the spinal segment (SS) 17-20 consisted of a mixture of crossed and uncrossed axons. SC neurons in the more cranial and caudal SS than SS 17-20 (transitional zone) were generally uncrossed and crossed, respectively. In the transitional zone, SC neurons in spinal border cells and ventral border cells of the ventral horn changed dramatically from an uncrossed to a crossed type between SS 17 and SS 18. Chicken SC neurons are markedly different in laterality from mammalian SC neurons.     

Effects of age and gonadal steroids on the localization of antigen presenting cells in the epididymis of the male chicken, Gallus domesticus

The goal of this study was to localize antigen presenting cells (APC), which may play roles in defense against pathogens and fertility, and examine the effects of age and gonadal steroids on their population in the rooster epididymis. Healthy White Leghorn male birds (immature 60-day-old birds; matured 150-, 330-, and 550-day-old), and immature birds treated with testosterone propionate (TP) or estradiol benzoate (EB) for 3 or 6 days were used. Cryostat sections of the epididymis and ductus deference were immunostained for Ia to identify APC. RT-PCR was performed to confirm the expression of major histocompatibility complex class II (MHC class II) mRNA in the epididymis. Ia+ cells were localized in the surface epithelium and subepithelial layer of the ductules and occasionally in the luminal content of the epididymis and ductus deference. RT-PCR analysis confirmed expression of MHC class II mRNA in the epididymis, ductus deferens, testis, and spleen. The frequency of Ia+ cells in the subepithelial layer was significantly greater in the proximal efferent ductules than in the other two types of ductules in the epididymis of 550-day-old birds. Although there were no significant differences in the frequencies in the subepithelial layer of the proximal efferent ductules between 60- and 150-day-old birds, the frequencies were significantly greater in 330- and 550-day-old birds than in 60-day-old birds. The frequencies of Ia+ cells in the ductus deferences was increased in the 150-day-old birds compared with the 60-day-old birds, with a larger increase in 330- and 550-day-old birds. The Ia+ cell frequency was significantly increased by EB-injection, but not by TP-injection, on Days 3 and 6 of injection compared with Day 0. These results suggest that the population of APC in the epididymis increases with age after sexual maturation, and estrogen may be one of the factors involved in induction of Ia+ cells.     

Effects of adding luteinizing hormone to a medium containing follicle stimulating hormone on progesterone-induced differentiation of cumulus cells during meiotic resumption of porcine oocytes

In the present study, we investigated the effects of adding luteinizing hormone (LH) to a medium containing follicle stimulating hormone (FSH) on the shift in expression of progesterone receptor (PR) isoforms (PR‐A and PR‐B) and the roles in function of cumulus cells of cumulus‐oocyte complexes (COC). The level of PR‐B mRNA in cumulus cells was up‐regulated by FSH during the first 16‐h cultivation but the level was significantly decreased at 20 h. The decrease of PR‐B mRNA was accelerated when COC were cultured with FSH and LH. Still, a high level of total PR mRNA was maintained in cumulus cells cultured with or without the addition of LH up to 20 h, suggesting that the expression of PR isoforms was shifted from PR‐B to PR‐A in cumulus cells. The reduction of PR‐B was also induced by addition of progesterone to FSH‐containing medium. The addition of LH or progesterone to FSH‐containing medium stimulated cumulus expansion of COC as compared with that of COC cultured with FSH. In the expanded COC, ADAMTS‐1 which is expressed in granulosa cells and cumulus cells in rodent follicles through LH‐induced progesterone‐ and PR‐dependent pathway, was more accumulated within the COC matrix. These results suggest that the addition of LH or progesterone to FSH‐containing medium is required for the differentiation of cumulus cells, such as cumulus expansion, mediated by the shift from PR‐B to PR‐A in them.     

Sequence analysis of the NRAMP1 genes from different bovine and buffalo breeds

The natural resistance associated macrophage protein 1 (Nramp1) has been reported to confer resistance or susceptibility to Mycobacterium bovis, Salmonella typhimurium, and Leishmania donovani in the mouse, Mus musculus. A Gly and Asp substitution at position 169 of the mouse Nramp protein is invariably associated with the resistant and susceptible phenotypes, respectively. The present study aimed to detect polymorphisms in the NRAMP1 gene from different cattle and buffalo breeds. Genomic DNAs from five breeds of cattle and four breeds of buffalo were used in the study. Sequencing showed two nucleotide substitutions found in intron 4, three in exon V, and ten in intron 5. An amino acid substitution was observed at nucleotide position 1202 in exon V of the Japanese black, Angus, Philippine and Bangladesh swamp-type buffaloes which coded for Thr, while the Korean cattle, Holstein, African N'dama, Indonesian swamp-type buffalo and the Bangladesh river-type buffalo had Ile. All the breeds of cattle and buffaloes tested in this study coded for Gly at the position in exon VI which corresponds to the same amino acid of the murine Nramp1-resistant phenotype at position 169. The phylogenetic relationship among the different breeds showed a cluster comprised mainly of cattle and another one mainly of buffaloes.     

Effects of lauric acid on physical, chemical and microbial characteristics in the rumen of steers on a high grain diet

The effects of being fed lauric acid on rumen characteristics were evaluated in a double 3 × 3 Latin square design using six Holstein steers with ruminal cannulas on a high grain diet. The steers were fed commercial concentrate (8.7 kg/day/steer) with one of three levels of lauric acid (0, 25 or 50 g/day/steer) and timothy hay (1.8 kg/day/steer). The feed intake and digestibility were determined. Ruminal fluid was collected at 3 h after feeding to determine chemical, physical and microbial parameters. An in vitro pure culture study was performed to determine the effects of lauric acid on Streptococcus bovis, a potent bloat‐ and acidosis‐promoting rumen bacterium. There were no differences in feed intake and digestibility among the treatments. The proportion of butyrate and the viscosity of the rumen fluid tended to be lowered (P < 0.08 and P < 0.09, respectively) and the stable ingesta volume increase was significantly decreased (P < 0.01) by the lauric acid feed. The abundance of protozoa and bacteria did not differ among the treatments. In the in vitro study, the growth of S. bovis was inhibited by the lauric acid (100 nmol/L) but it showed an adaptive growth to lauric acid in long‐term subculturing. The S. bovis that had adapted to lauric acid showed decreased viscosity and lactate production (P < 0.01) in culture with sucrose. These results indicate that supplemental lauric acid added to a high grain diet improves physical properties, possibly by altering the metabolic activity of S. bovis, and it may prevent the occurrence of feedlot bloat and acidosis in beef cattle.     

Chemistry of Fog Water Collected in the Mt. Rokko Area (Kobe City, Japan) between April 1997 and March 2001

Fog chemistry was studied for four years (April 1997–March 2001) at Mt. Rokko (altitude 931 m) in Kobe, Japan. A collection of samples was obtained at a mountainous site close to a highly industrialized area. The samples were collected by an active string-fog collector. The summer fog was dense and frequent. The geography of Mt. Rokko is linked to the seasonality of the occurrence and the thickness of the fog. Among the meteorological parameters, the relative humidity was important for the occurrence of fog. The correlation of the concentrations of the components in fog water indicated that (NH₄)₂SO₄ and/or NH₄HSO₄ were involved in the process of the formation of fog drops in the atmosphere. The concentration of the components decreased with an increase in the liquid water content (LWC) of the fog, and the seasonal variation of the concentration of some components depended on the seasonal variation of the LWC. The equivalent ratio of NO₃ ^? to non-sea salt (nss?) SO₄ ^2? was considerably larger than that in precipitation. Ammonium ion accounted for the largest percentage of cations, which indicates that NH₄ ⁺ was an important counter cation for NO₃ ^? and nss-SO₄ ^2?. A unique fog event in which the air pollutants seemed to be scavenged stoichiometrically was sometimes observed. The methodology used for collecting fog water at 60 mL intervals provided detailed information.     

Spatial Variations and Trends in Acid Deposition in Japan Within a 100 Km × 100 Km Region from 1989 to 1999

Water, Air, &; Soil Pollution - A monitoring network for acid deposition that consisted of five sites in Hyogo, Japan, and covered a region of about 100 km × 100 km revealed the spatial...     

Cloud Water Deposition to Forest Canopies of Cryptomeria Japonica at Mt.Rokko, Kobe, Japan

Cloud water deposition to canopies of Cryptomeria japonica at Mt.Rokko, Kobe, Japan, was estimated from throughfall measurements and fog water collections carried out during a full year. Annual cloud frequency was 11.5–15.5% and liquid water content (LWC) was 0.059 g/m³. Since cloud water deposition on to forest canopies was significantly correlated with the amount of fog water collected, the former parameter could be quantitatively derived from throughfall measurements. Annual cloud water deposition on to Cryptomeria canopies was 1420–2860 mm (Av. 2140 mm), corresponding to 90–180% (Av. 122%) of annual rainfall. The rate of deposition was higher at the mountain ridge and the forest edge than at the mountain side and the forest interior. Annual deposition of SO₄ ^2?, NO₃ ^?, H⁺ and NH₄ ⁺ from cloud water was estimated as 204, 153, 2.5 and 58 kg/ha, respectively, equivalent to 5.8–11.7 times the corresponding deposition via rain. The values are equal to, or exceed, the maximum deposition reported for Appalachian forests in the eastern United States. Multiple regression analyses indicate that cloud water deposition on to Cryptomeria canopies was significantly correlated with the following three parameters: cloud frequency, LWC, and wind speed. Thus, these three factors apparently control cloud water deposition on to forest canopies.     

Types of frass produced by the ambrosia beetle <Emphasis Type="Italic">Platypus quercivorus</Emphasis> during gallery construction,and host suitability of five tree species for the beetle

We studied the biology of the ambrosia beetle Platypus quercivorus in the logs of five tree species to determine: (1) the relationship between the amount of frass produced by beetles and tunnel length, (2) the relationship between frass shape and the morphological characteristics of P. quercivorus mouthparts, and (3) the suitability of five tree species for P. quercivorus reproduction. Five logs each from healthy Quercus crispula, Q. serrata, Castanea crenata, Sorbus japonica, and Cryptomeria japonica trees were used in this experiment. The results showed that there was a linear relationship between the amount of frass and tunnel length. Whenever powdery frass was produced, larvae were found in the gallery in the log, while fibrous frass was present only in galleries that contained just adults. The mouthparts of adults were completely sclerotized, which likely accounts for the fibrous frass production. Host preference of P. quercivorus was examined at two stages using five tree species. The first stage is digging initiation, which concerns male preference for digging a tunnel. More holes were made by males on S. japonica and Q. serrata logs, while fewer holes were made on C. japonica logs. The second stage is characterized by female orientation, mating, and progeny development. Platypus quercivorus could complete its lifecycle only in the two Quercus spp.