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91.
There are no accurate reference ranges for hematology parameters and lymphocyte subsets in Korean native beef cattle (Hanwoo). This study was performed to establish reliable reference ranges of hematology and lymphocyte subsets using a large number of Hanwoo cattle (n = 350) and to compare differences between Hanwoo and Holstein dairy cattle (n = 334). Additionally, age‐related changes in lymphocyte subsets were studied. Bovine leukocyte subpopulation analysis was performed using mono or dual color flow cytometry. The leukocyte subpopulations investigated in healthy cattle included: CD2+ cells, sIgM+ cells, MHC class II+ cells, CD3+CD4+ cells, CD3+CD8+ cells, and WC1+ cells. Although Hanwoo and Holstein cattle are the same species, results showed several differences in hematology and lymphocyte subsets between Hanwoo and Holstein cattle. This study is the first report to establish reference ranges of hematology and lymphocyte subsets in adult Hanwoo cattle.  相似文献   
92.
With the view to complementing the feedstuff data store and, consequently, to further improving the GDR Feed Evaluation System, some newly bred high-protein and/or high-lysine cereal varieties and strains (spring barley, winter wheat, maize) were studied for their nutrient composition and digestibility. Apart from from WEENDER's feed analysis technique, more recent methods were applied to determine total fat (after HCl treatment), carbohydrates (enzymatic method), lignin and amino acids. The digestibility of the nutrients was determined using growing pigs of different live weight, the test rations being made up of the cereals under and supplementations of limiting amino acids as well as vitamins and minerals. In comparison with the values from currently applied tables, the newly bred strains and varieties proved to have markedly higher contents of crude protein, digestible crude protein, lysine and energetic feed equivalents. Compared to crude fat, the total fat values proved markedly higher in the barley and wheat samples. The readily soluble and easily hydrolizable carbohydrates found with the new analysis procedure suggested, were 100% digestible in all cereal samples used. Lignin proved the constituent most difficult to digest and must be regarded as virtually undigestible in the case of pigs.  相似文献   
93.
Avian influenza and hemorrhagic enteritis viral preparations were immunoelectrophoresed in a phosphate-buffered system. Excellent separation and resolution of viral proteins were achieved. Reasons are given why this method might be preferred over the conventional method employing a veronal (barbital)-buffered system.  相似文献   
94.
Tick fever is an important disease of cattle where Rhipicephalus (Boophilus) microplus acts as a vector for the three causal organisms Babesia bovis, Babesia bigemina and Anaplasma marginale. Bos indicus cattle and their crosses are more resistant to the clinical effects of infection with B. bovis and B. bigemina than are Bos taurus cattle. Resistance is not complete, however, and herds of B. indicus-cross cattle are still at risk of babesiosis in environments where exposure to B. bovis is light in most years but occasionally high. The susceptibility of B. indicus cattle and their crosses to infection with A. marginale is similar to that of B. taurus cattle. In herds of B. indicus cattle and their crosses the infection rate of Babesia spp. and A. marginale is lowered because fewer ticks are likely to attach per day due to reduced numbers of ticks in the field (long-term effect on population, arising from high host resistance) and because a smaller proportion of ticks that do develop to feed on infected cattle will in turn be infected (due to lower parasitaemia). As a consequence, herds of B. indicus cattle are less likely than herds of B. taurus cattle to have high levels of population immunity to babesiosis or anaplasmosis. The effects of acaricide application on the probability of clinical disease due to anaplasmosis and babesiosis are unpredictable and dependent on the prevalence of infection in ticks and in cattle at the time of application. Attempting to manipulate population immunity through the toleration of specific threshold numbers of ticks with the aim of controlling tick fever is not reliable and the justification for acaricide application should be for the control of ticks rather than for tick fever. Vaccination of B. indicus cattle and their crosses is advisable in all areas where ticks exist, although vaccination against B. bigemina is probably not essential in pure B. indicus animals.  相似文献   
95.
Proximate composition, total dietary fiber and pH of tomatillos (Physalis ixocarpa) grown in Baja, California were analyzed. Moisture content averaged 92%. On a dry matter basis (DMB), tomatillos contained 11% protein, 18% fat, 13% ash and 5% total dietary fiber. On an as consumed basis (ACB), tomatillos contained 1% protein, 1.5% fat, 1% ash and 0.4% dietary fiber. Carbohydrate (CHO) content was calculated by difference resulting in an average adjusted CHO (excluding dietary fiber) of 53% on a DMB and 4% on an ACB; total CHO (including dietary fiber) was 58 and 4.8%, respectively. Average kcalorie content was calculated to be about 31 kcals/100 g. The average pH of tomatillos was 3.76.  相似文献   
96.
Seismic rupture produced spectacular tectonic deformation above a 400-kilometer strip of the Sunda megathrust, offshore northern Sumatra, in March 2005. Measurements from coral microatolls and Global Positioning System stations reveal trench-parallel belts of uplift up to 3 meters high on the outer-arc islands above the rupture and a 1-meter-deep subsidence trough farther from the trench. Surface deformation reflects more than 11 meters of fault slip under the islands and a pronounced lessening of slip trenchward. A saddle in megathrust slip separates the northwestern edge of the 2005 rupture from the great 2004 Sumatra-Andaman rupture. The southeastern edge abuts a predominantly aseismic section of the megathrust near the equator.  相似文献   
97.
Samples from the antrum and fundus of the stomachs of 457 pigs from 22 different herds were screened for the presence of 'Candidatus Helicobacter suis' by pcr, and samples from the antrum and/or fundus of 222 of the stomachs were tested for urease activity. The prevalence of the infection was very low before weaning, increased rapidly after weaning and reached 90 per cent in the adult boars and sows. The agreement between the results obtained with the pcr test and the urease test was very good for some age groups and sampling sites, but poor for other age groups and sampling sites.  相似文献   
98.
The network‐forming attributes of gluten have been investigated for decades, but no study has comprehensively addressed the differences in gluten network evolution between strong and weak wheat types (hard and soft wheat). This study monitored changes in SDS protein extractability, SDS‐accessible thiols, protein surface hydrophobicity, molecular weight distribution, and secondary structural features of proteins during mixing to bring out the molecular determinants of protein network formation in hard and soft wheat dough. Soft wheat flour and dough exhibited greater protein extractability and more accessible thiols than hard wheat flour and dough. The addition of the thiol‐blocking agent N‐ethylmaleimide (NEM) resulted in similar results for protein extractability and accessible thiols in hard and soft wheat samples. Soft wheat dough had greater protein surface hydrophobicity than hard wheat and exhibited a larger decrease in surface hydrophobicity in the presence of NEM. Formation of high‐molecular‐weight (HMW) protein in soft wheat dough was primarily because of formation of disulfides among low‐molecular‐weight (LMW) proteins, as indicated by the absence of changes in protein distribution when NEM was present, whereas in hard wheat dough the LMW fraction formed disulfide interaction with the HMW fraction. Fourier transform infrared spectroscopy indicated formation of β‐sheets in dough from either wheat type at peak mixing torque. Formation of β‐sheets in soft wheat dough appears to be driven by hydrophobic interactions, whereas disulfide linkages stabilize secondary structure elements in hard wheat dough.  相似文献   
99.
Field investigations of protection afforded by live Babesia bovis vaccine in Australia revealed that a ninefold increase in vaccine failures occurred in the period from 1985 to 1990. Laboratory trials using 189 experimental cattle were conducted to evaluate the protection afforded by the Babesia bovis strain used in the commercial vaccine during this time. Four isolates from clinical cases of babesiosis in vaccinated cattle were assessed. The results showed that the strain used in the vaccine during the 5 year period was poorly protective against three isolates while a recently isolated and prepared vaccine strain was strongly protective. Circumstantial evidence is provided that indicates the vaccine failures were due to change in the field populations of Babesia bovis, rather than change in the strain used in the vaccine. Implications of the results for the future of Babesia bovis vaccines are discussed.  相似文献   
100.
Summary The expression of self-incompatibility (SI) rejection patterns in 29 accessions of wildBeta species was studied at the anatomical level. Three different SI-related pollen tube rejection patterns were observed: (1) The pollen germinate from many pores and the pollen tubes are very short, often with swollen tips. (2) The pollen germinate and grow along the stigmatic papillae, where the self-incompatibility response takes place at the basis of the stigmatic papillae. (3) The pollen germinate and the pollen tubes grow with a distinct direction towards the style; the self-incompatibility response is observed at the border between the stigma and the style. In general the patterns observed inB. vulgaris L. subsp.vulgaris sensu lato seem to be in accordance with an ongoing microevolutionary process that has given rise to the largemaritima complex (viz.B. trojana Pamuk?uoğlu,B. atriplicifolia Rouy, andB. maritima (L.) Arcangeli), in which it seems that the variation is related to geographical origin. The data support the idea that the endemicB. vulgaris subsp.adanensis (Pamuk?uoğlu) Ford-Lloyd & Williams forms a distinct, self-compatible group separated from themaritima complex and also thatB. macrocarpa Gussone should be retained as a separate self-compatible species. For the sectionCorollinae Ulbrich the rejection patterns are in accordance with a division into two subsections (viz.,Lomatogonae andTrigynae) previously suggested on the basis of phenotypical and molecular data. The results fromProcumbentes Ulbrich are interpreted as evidence forB. procumbens Smith andB. webbiana Moquin being more related to each other than toB. patellaris Moquin, reflecting also a similar taxonomic relationship.  相似文献   
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