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21.
A system was designed to allow a small swine farm in a northern latitude to use its own boars for artificial insemination (AI) conveniently. Semen was collected twice weekly for 3 day use (days 0, 1 and 2), extended in an egg yolk extender and stored at 5°C. Farm personnel were trained to manage the entire AI programme. For simplicity all semen collected was used for insemination. In the first test 47 gilts and 15 sows were inseminated with semen from four boars. One boar was subfertile with a farrowing rate of 36%. The averages for the other boars ranged from 71 to 100%. Then semen was collected from seven boars and all was used to inseminate 70 gilts and 55 sows with 3 × 109 or more sperm. Overall 63% farrowed an average of 10.1 piglets per litter. Litter size for sows was 1.5 piglets larger than for gilts. There was no difference in farrowing rate when more than 3 × 109 sperm were inseminated. The feasibility of initiating a complete AI programme within a small herd using herd boars was established. However, selection of the boars, use of only high quality semen, and experience with detecting oestrus was required to increase the farrowing rate. The use of various agents to protect sperm against cold shock below 15°C is worthy of further investigation. A new type of electronic probe, which measures the conductivity of cervical mucus, could be helpful if a boar is not available for conventional detection of oestrus.  相似文献   
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Atrioventricular valve dysplasia in Dalmatians   总被引:1,自引:0,他引:1  
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23.
Rare crystal phases that expand in one or more dimensions when hydrostatically compressed are identified and shown to have negative Poisson's ratios. Some of these crystals (i) decrease volume and expand in two dimensions when stretched in a particular direction and (ii) increase surface area when hydrostatically compressed. Possible mechanisms for achieving such negative linear and area compressibilities are described for single crystals and composites, and sensor applications are proposed. Materials with these properties may be used to fabricate porous solids that either expand in all directions when hydrostatically compressed with a penetrating fluid or behave as if they are incompressible.  相似文献   
24.
Abstract

Extract

Hypoadrenocorticism, or Addison's disease, is an uncommon en-docrinopathy of dogs (Feldman and Nelson 2004 Feldman, EC and Nelson, RW. 2004. “Hypoadrenocorticism (Addison's disease)”. In Canine and Feline Endocrinology and Reproduction, 3rd, 394439. Philadelphia, , USA: WB Saunders.  [Google Scholar]). Long-term management of affected dogs in New Zealand involves treatment with oral fludrocortisone acetate (Florinef tablets; Bristol-Myers Squibb (NZ) Ltd, Auckland, NZ), which is a relatively expensive synthetic adrenocortical steroid. Table salt may be added to the food, in an attempt to reduce the amount of fludrocortisone required. Despite fludrocortisone therapy, many Addisonian dogs remain hyponatraemic and hyperkalaemic and the required dose of fludrocortisone may need to be increased during the first year of treatment. Increasing the dose of fludrocortisone is not only expensive, but may also have undesirable effects through its potent glucocorticoid action.  相似文献   
25.
A double-antibody-sandwich ELISA test has been developed for the detection of Pseudocercosporella herpotrichoides using a highly specific monoclonal antibody PH-10 as the capture antibody and genus-specific rabbit polyclonal antiserum as the detector antibody. The assay recognizes extracts from plants both artificially and naturally infected with P. herpotrichoides giving at least three-fold higher absorbance values with extracts from Pseudocercosporella-infected tissue than with extracts from healthy tissues or from tissues naturally infected with Microdochium nivale, Rhizoctonia cerealis or material artificially inoculated with P. anguioides. The assay tested positively against all isolates of P. herpotrichoides , including both W-type and R-type isolates. In this assay system, extraction of the antigen from the stem bases of infected plants is a one-step process not requiring any dilution procedures. The assay can be used to detect the pathogen in presymptomatic infected seedlings. The immunogen used to generate the specific monoclonal antibody and the rabbit antiserum was a mycelial extract from which the high-molecular-weight proteins and glycoproteins had been removed by ammonium sulphate precipitation. The high-molecular-weight fraction was shown to contain cross-reactive antigens; it induced antiserum in mice that cross-reacted with the other stem-base fungi even at high dilutions. The monoclonal antibody PH-10 is an IgM antibody. Heat and periodate treatment of the antigen indicate that it is a glycoprotein and that the epitope recognized by the antibody is a protein.  相似文献   
26.
The results of 21 winter wheat and 32 spring barley trials done in the United Kingdom showed that cultivars differed significantly in their yield response to a standard fungicide treatment. Regression analyses showed that yield responses were significantly related to disease reduction, particularly that of mildew, although the proportion of variance accounted for was small. Measurements made on seven winter wheat trials indicated that the percentage of leaf area remaining green after anthesis was increased by the fungicide treatment to a greater extent than could be attributed to disease reduction alone. In some of these trials, yield responses were more closely correlated with the increase in leaf area remaining green than with disease reduction.  相似文献   
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The aim of this was to investigate the histology and immunohistochemistry of interstitial glands during non‐breeding season in camel ovaries. A total of 21 mature, non‐pregnant and apparently healthy camels aged between 8 and 12 years were slaughtered. The ovaries were removed within 15 min, cleaned from adipose tissue, weighted and examined grossly. The histological preparation was made, and then, the blocks were cut at 3–5 microns thickness and stained by H&E for histological examinations. Moreover, some sections were stained with Sudan Black for lipid detection. Immunohistochemical analysis of paraffin‐embedded ovarian tissues was performed to detect the localization of S‐100, vimentin, progesterone receptors (PR) and oestrogen receptors (ER). Immunoreactive signals were detected using UltraVision Detection System. The results revealed that the interstitial glands were located in the cortical region and they were arranged in various arrangements either single, in couple or in groups rich in lipid droplet. All interstitial gland arrangements were enclosed by connective tissue capsules containing fibroblasts and collagenous fibres separated them from the surrounding ovarian structures. Both interstitial glands and their surrounding CT were penetrated by several blood vessels. There was a strong immunoreactive signal for S‐100 in the nuclei of interstitial cells, and no signals were detected either in cells of the interstitial glands or their connective tissue with PR. We could conclude that the interstitial gland is distinct in ovary of camel and further studies are needed to elucidate its rule in steroid synthesis.  相似文献   
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