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671.
In this study, IgG subclass responses against equine herpesvirus type 4 (EHV-4) were examined by enzyme-linked immunosorbent assay (ELISA) using a type-specific region of EHV-4 glycoprotein G (gG). ELISA using sera collected from horses experimentally infected with EHV-4 revealed that IgGa and IgGb antibodies were detected at high level, but IgGc and IgG(T) antibody responses were detected at low level or were undetectable. The IgGa antibody response reached its peak on day 10 post-infection, and then dropped. The IgGb antibody response reached its maximum level on day 12 post-infection, and then the level was sustained during at least 28 days after infection. Forty healthy racehorses that had already been infected with EHV-4 possessed antibody against EHV-4. Although IgGa antibodies specific for EHV-4 were not detected in any horses, IgGb antibodies were detected and the levels correlated with total IgG antibodies against EHV-4 gG. The results suggest that EHV-4-specific IgGa and IgGb antibodies are induced in EHV-4-infected horses, and that IgGb antibody, but not IgGa, is long lasting.  相似文献   
672.
A total of 1,013 feces samples and 8 mesenteric lymphonodus samples obtained from apparently healthy dogs were examined for the incidence of salmonella infection. One strain of S. typhimurium (ST) was isolated from feces of one dog, and S. enteritidis (SE) was isolated from the mesenteric lymphonodus of one dog. Sera obtained from 330 apparently healthy dogs were examined for Salmonella antibodies using an ELISA with heated whole cells of SE and ST. Fifty-one of the 330 serum samples were considered to be positive for salmonella antibodies, including 12 which were SE-positive and 39 which were ST-positive. These results indicate that dogs cause possible environmental problems as Salmonella carriers.  相似文献   
673.
Analyses of patrol videos that record the circumstances of race accidents was made. Many of the serious accidents that occur in the course of races involve fracture or dislocation of the component bones of the fetlock joint. A large percentage of these occurred on the leading leg, regardless of whether the horses were running clockwise or counterclockwise direction. Many of these accidents occurred during changes in lead, with the accidents occurring at the moment when a limb made contact with the ground. Differences in the location of musculoskeletal injuries were observed in accidents that occurred in the straightaway portion of the track, while moving out of turns to the straightaway; and while in the turn.  相似文献   
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676.
Shortened and weakened oestrous signs in dairy cows may cause a failure of oestrus detection and artificial insemination timing error leading to poor reproductive performance. The aims of this study were to investigate the duration of standing oestrus in high-producing dairy cows under a free stall system, to determine the duration of expression of secondary oestrous signs before and after standing oestrus (Expt 1) and to compare the duration and intensity of oestrus between cows and heifers (Expt 2). Cattle were checked for primary and secondary oestrous signs at an interval of 4 h. Heat detection aids were also used. In Expt 1, of 56 cows which were detected in oestrus, 36 cows (64.3%) showed standing oestrus and other 20 cows (36.6%) showed secondary oestrous signs only. Duration of the standing oestrus was 6.6 +/- 6.3 h on average (+/-SD), ranging between 2 and 32 h. The cows in standing oestrus showed secondary oestrous signs during a period from 9.6 +/- 8.1 h before onset of standing to 18.4 +/- 18.8 h after the end of standing oestrus. In the cows that did not show standing oestrus, expression of secondary oestrous signs were observed for 25.7 +/- 20.5 h, which was 7.5 h shorter than the average duration of oestrus in cows showing standing oestrus. In Expt 2, nine (82%) of the 11 lactating cows in oestrus showed standing, while all the 10 heifers exhibited standing oestrus. Average duration of standing oestrus was 6.4 +/- 4.3 h in cows and 6.2 +/- 3.9 h in heifers, respectively. It may be concluded that the duration of standing oestrus is substantially shortened in lactating dairy cows, and more than one-third of cows did not show standing oestrus. In cows showing standing oestrus, duration of expression of secondary oestrous signs before and after standing is not shortened. Duration of standing oestrus in heifers was as short as that in cows.  相似文献   
677.
Introduction

As a result of the H-bomb explosion tests of the U.S.A. in the Southern Pacific Ocean, rain-out in Japan is contaminated considerably by fission products, and field crops also show apparently artificial radioactivities. Many workers are now investigating to clarify degree and regional extent of contamination or sorts of radioactive elements.  相似文献   
678.
There is no doubt that the life cycle of crop plants depends on two fundamental metabolic processes: photosynthesis and nutrient absorption. When these two important functions are considered in connection with morphology of crops, we can easily find out the differentiation of functions, that is, photosynthesis by green leaves and nutrient absorption by roots. In the past, a number of investigations have been made on these two functions of rice plants, the physiology of their leaves as photosynthetic organ has also been studied in detail. On the physiology of roots, however, knowledge which we have today is not as detailed as is deemed necessary.  相似文献   
679.
In the previous paper1), we compared the in. organic composition of root with that of shoot of rice plant at successive growth stages, and revealed that the content of inorganic elements in root was generally lower than that in shoot, and that paddy root, sending most of absorbed salts to the top, does not possess a function to store inorganic nutrients.  相似文献   
680.
In the previous studies we investigated some characteristics of paddy root in comparison with shoot by analysis of inorganic elements1) and metabolizable forms of organic compounds2) of shoot and root at successive growth stages, and found that the contents of the above-mentioned components in root were generally lower than those in shoot with few exceptions. From this it is concluded that in root the contents of the residual components, mainly cell wall substances, must be high. To ascertain this surmise, we carried out analysis of shoot, root and inflorescences of rice plant with respect to hemicellulose, cellulose and lignin which construct cell walls.  相似文献   
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