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421.
The electrophoretic variation in bovine hemoglobin‐beta (HBB) is one of the most investigated genetic markers. The presence of a unique HBB variant, HBBX, 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 HBBX in domestic cattle had dimorphism and was separated into HBBX1 and HBBX2. The HBBX1 had the same DNA sequence of the common HBB variant in gayal (Bos gaurus frontalis), while some of the HBBX2 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 HBBX1 was always predominant to HBBX2 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.  相似文献   
422.
We conducted applicability evaluation of recommendations of the European Union (EU) and the Royal Society for Prevention of Cruelty to Animals (RSPCA) for suckling calves. Nineteen calves (14 Holstein aged 11–26 days and five cross‐bred aged 13–45 days) were divided into six groups. Three groups were allocated into the stocking densities of 0.25, 0.35, 0.45 m2/head and were weekly transported 50, 100, 150 km in this order. Another three groups were allocated and transported in reverse order. Observation was conducted during and after transportation. Blood sampling was performed before and after transportation. The occurrences of lying and turning round on the truck were significantly associated with stocking density (P < 0.05), but not with haul distance. Scratching was observed only in one calf. Incidence of watery feces was not associated with both factors. There were significant effects of haul distance on the concentrations of plasma cortisol and noradrenaline, and serum aspartate aminotranserase (AST) and IgM (P < 0.05). These concentrations, except cortisol, were higher after transportation at 150 km compared to the pre‐transportation value (AST and IgM P < 0.05; noradrenaline P < 0.10). Results suggest that haul distances greater than 100 km should not be recommended even for suckling calves transported in Japan.  相似文献   
423.
Leukemia inhibitory factor (LIF) is essential for embryo implantation in mice and plays an important role in other mammals including humans. Intraperitoneal (i.p.) injections with anti-LIF antibody (7.5 μg/g body weight, 3 times) between D3 (D1 = day of vaginal plug detection) and D4 effectively blocked embryo implantation; complete inhibition was achieved in C57BL/6J mice, and implantation was dramatically reduced in ICR mice (reduced to 27%). Normal rabbit IgG used as the control did not disturb embryo implantation. Anti-LIF antibody was localized not only in the stroma, but also in the luminal epithelium and the glandular lumen after i.p. injections. Growth-arrested blastocysts were recovered from the uterus without any implantation sites in both strains. Blastocysts made contact with the LE on the antimesometrial side; however, uterine stromal cells did not undergo secondary decidual reaction, and the uterine lumen was open, even at D7. Several regions of decidualization in ICR mice treated with anti-LIF antibody were smaller than those of the control, and development of blastocysts was delayed. The expression of LIF-regulated genes, such as immune-responsive gene-1 and insulin-like growth factor binding protein-3, was significantly decreased in C57BL/6J mice treated with anti-LIF antibody compared with the control, but not in ICR mice. The present study demonstrated that simple ip injections of an antibody are sufficient to block one of the important factors involved in embryo implantation in mice, and this method should also be easily applicable to the investigation of other factors involved in implantation.  相似文献   
424.
To determine whether functional T- and B-cells can affect differentiation and/or proliferation of uterine natural killer (uNK) cells, their numbers in SCID mice (genotype, C.B.-17/Icr-scid/scid) were compared with those of control mice (genotype, C.B.-17/Icr-+/+) on days 8, 12 and 16 of pregnancy. Using biotinylated-Dolichos biflorus agglutinin (DBA) lectin staining, uNK cells can be readily classified into 4 subtypes, I to IV, from immature to mature types. The number of uNK cells was significantly lower in the decidua basalis of SCID mice than in that of control mice on day 8 of pregnancy. Particularly, the number of uNK cells of immature subtype II was significantly lower in SCID mice than in the control mice. By day 12, however, the uNK cell number in the SCID mice reached the same level as that of the control mice. It is likely that uNK cell differentiation in SCID mice was delayed during the early placentation period due to a lack of functional T and B cells.  相似文献   
425.
426.
To investigate the role of the proteinaceous elicitor, harpin, on host and nonhost plants, we isolated the harpin-coding gene, hrpZ, from Pseudomonas syringae pvs. pisi, glycinea, tabaci and tomato. Effects of the recombinant harpin proteins on pea plants were analyzed and compared with the effects of the corresponding bacterial treatment. After inoculation of pea with pea pathogen P. syringae pv. pisi, the bacterial population increased and the accumulation of PAL-mRNA and pisatin was inhibited. The nonpathogenic pathovars, glycinea, tabaci and tomato induced both defense responses in pea. However, none of the harpins induced the hypersensitive reaction or accumulation of PAL-mRNA and pisatin in pea. Harpins from P. syringae pvs. glycinea, tomato and pisi did induce these defense responses in tobacco, however, suggesting that externally applied harpins either are not recognized or are nonfunctional in pea plants. Received 27 June 2000/ Accepted in revised form 21 February 2001  相似文献   
427.
In sequential transmission tests of Peanut stunt virus S (PSV-S) and Cucumber mosaic virus V (CMV-V) using Myzus persicae, these viruses behave as a semipersistent virus in Phaseolus vulgaris, but as a nonpersistent virus in Nicotiana tabacum, regardless of the species of plant used as the virus source. In addition, viruliferous aphids retained virus infectivity and transmitted it to P. vulgaris, even after they lost infectivity to N. tabacum. Apparently, the mode of transmission by the aphids differs depending on the plant species used for the assay. After mechanical inoculation with purified PSV-S or CMV-V, P. vulgaris appeared more susceptible to PSV-S than N. tabacum. However, the susceptibility to CMV-V appeared similar in both assay plants. Received 22 May 2000/ Accepted in revised form 14 September 2000  相似文献   
428.
To consider cattle welfare, time budget of behaviors of young cattle in pen and pasture conditions were compared. Behavioral observations of 103 steers in seven pens and 1136 steers in six ranges were performed during daylight over 3 days in each rearing condition. The pen condition had Japanese Black × Holstein cross, and the pasture conditions had assorted breeds of Angus, Murray Grey, Shorthorn, Hereford, Santa Gertrudis and their crosses aged 5–15 months. The ranges varied in vegetation from extensive native pasture to intensive improved pasture. The daytime proportion of behaviors and activity patterns were compared between rearing conditions. The proportion of walking was much lower in the pen condition (1.0 ± 0.2%) compared to all pasture conditions (at least 9.4 ± 4.0%; all P < 0.05), but grooming (5.9 ± 1.2%), investigating (2.5 ± 0.2%) and tongue playing (1.1 ± 0.2%) covered the loss. Fluctuation patterns of the proportions of eating (P < 0.001) and resting (P < 0.001) were different between pen and pasture conditions, whereas the pattern of the proportion of walking was not different. The proportion of eating in the pen condition (32.4 ± 0.3%) was not different to that in one on the farm (42.2 ± 12.6%), which had a thick improved pasture. However, the proportion of eating in the pen condition (32.4 ± 0.3%) was lower than that in two farms (58.8 ± 5.0% and 61.6 ± 16.5%) with low pasture availability (both P < 0.05). The proportions of oral behaviors such as self‐grooming (3.9 ± 1.0%), allogrooming (2.0 ± 0.2%), licking objects (1.3 ± 0.4%) and tongue‐playing (1.1 ± 0.2%) compensated for the lack of eating. These results indicate that we can learn a well‐balanced proportion of behaviors for cattle by making comparisons of time budget of behaviors and activity pattern between various rearing conditions. In addition, it is indicated that cattle under pen conditions under a restricted feeding period might compensate for a lower time spent feeding by performing other oral behaviors.  相似文献   
429.
We studied in vivo fiber digestibility and fermentation parameters such as volatile fatty acid concentration and in vitro degradation in each segment of hindgut of horses fed timothy hay or silage made from the same sward. Six Thoroughbred horses were fed timothy hay or silage in equal amounts (1.6% of bodyweight per day, bodyweight mean 572 kg) every 3 h per day, then slaughtered. There were no differences between hay and silage in the concentration of the total volatile fatty acids, the apparent digestibility of dry matter, organic matter, and fiber, and in vitro neutral detergent fiber (NDF) disappearance rate in each segment. The total volatile fatty acid concentration and the apparent digestibility of dry and organic matter and fiber differed ( P  < 0.01) depending on the digestive segments. Both for hay and silage, the concentration of total volatile fatty acids in the digesta liquid phase largely increased ( P  < 0.01) from the cecum to the right ventral colon, and kept a constant value from the right ventral colon to the right dorsal colon, and then decreased from the right dorsal colon to the small colon. For dry and organic matter and fiber components, the apparent digestibility changed in the same manner from former to hinder segments of the hindgut. Regardless of diet, dry and organic matter and fiber components showed lower values in the cecum and the right ventral colon and increased ( P  < 0.01) largely from the right ventral colon to the left dorsal colon, then kept constant values in segments to the rear of left dorsal colon. There were no differences in in vitro NDF disappearance among cecum, ventral colon and dorsal colon.  相似文献   
430.
European Journal of Plant Pathology - To investigate the current status of viroid infection in potato fields in Russia, potato spindle tuber viroid (PSTVd) and chrysanthemum stunt viroid (CSVd)...  相似文献   
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