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121.
Dietary hypersensitivity is an uncommon condition which can result in a variety of dermato-logical and gastrointestinal signs. The major emphasis in management is on elimination of the causative agent from the diet. Correct diagnosis and implication of the offending allergen are prerequisites for optimal therapy. If this proves impossible, or if multiple sensitivities preclude formulation of an appropriate diet, corticosteroids or other anti-inflammatory agents must be employed and are variably effective.  相似文献   
122.
123.
Bovine follicular oocytes collected from bovine ovaries were exposed to bovid herpesvirus 1 (BHV-1). After washings, these oocytes were cultured to mature. As a result BHV-1 could not be removed from the oocytes and could replicate in the oocytes with cumulus cells, but not in the oocytes without the cells. Moreover, the specific fluorescence for BHV-1 was detected in the cumulus cells by a indirect immunofluorescent technique. Therefore these findings suggested BHV-1 could be absorbed in the oocytes but the replication of BHV-1 was done in the cumulus cells.  相似文献   
124.
Oxygen depletion is a serious problem for the catfish industry, especially as producers attempt to increase their production intensity. Aeration, either emergency or continuous, is the most common method used to address oxygen depletion.
A risk-programming model using Target MOTAD methodology was developed to study the aquacultural producer's aeration decision-making process. Effects of stocking rate, aeration yield response and availability of labor, capital and electricity on the selection of aeration strategy were analyzed.
Continuous aeration with electric paddlewheels was most often selected as the best aeration strategy. However, as farmers become increasingly concerned with financial risk, they apply continuous aeration with pump sprayers first, then no aeration and lastly emergency aeration with tractor-powered paddlewheels. Emergency aeration was only used when: 1) electricity was not available and the producer desired a highly conservative financial strategy, and 2) the relative efficiency of continuous aeration in the field was dramatically reduced from experimental results.  相似文献   
125.
Water-stable macro-aggregate size fractions (>2.0 mm, 1.0–2.0 mm, 0.5–1.0 mm and 0.25–0.5 mm) and non-aggregated soil from a sandy loam under long-term clover-based pasture and from grass pasture were analysed to determine the role of acid- and water-extractable carbohydrate C, total hyphal length, microbial biomass, organic C and total and mycorrhizal root length in stabilization of the aggregates. Aggregates were examined by scanning electron microscopy (SEM) and the particle-size distribution of the size fractions was also determined. Macro-aggregation increased under grass, relative to clover-based pasture; however, the properties of the aggregate fractions measured did not reflect this difference. Microbial-biomass C, extractable-carbohydrate C, hyphal length, total and mycorrhizal root length and organic C content of the soils were poorly correlated with macro-aggregation. Within the aggregates, the proportion of 250–1000-km sand was smaller and clay, silt and fine sand (20–250 μm) were greater relative to non-aggregated soil, suggesting that the >250-μm sand in the non-aggregated soil limited the stabilization of macro-aggregates. Under SEM, no enmeshment of aggregates by hyphae and roots was apparent. Although 50–160 m hyphae g?1 soil was found within the aggregates, calculations showed that on average only 5 to 13 lengths of hyphae were associated with each 250-μm cube of soil within the aggregates, and suggested little potential to stabilize the aggregates by enmeshing. On average, all >2.0-mm aggregates contained less than 3.6 mm of roots and less than 50% by weight of <2.0-mm aggregates contained a single length of root. The findings cast doubt about the role of hyphae and fine roots in the stabilization of macro-aggregates through an enmeshing mechanism in sandy soils.  相似文献   
126.
Due to the potential for anti-erythrocyte membrane antibodies as possible enhancers of erythrocyte destruction, the presence of serum anti-erythrocyte membrane antibodies in 31 dogs with Babesia gibsoni infection admitted to a veterinary hospital was investigated by an enzyme linked immunosorbent assay (ELISA) and immunoblotting analyses. This infection resulted in an increase of anti-erythrocyte membrane antibodies in 84% (IgG) and 74% (IgM) of 31 infected dogs, respectively. This was confirmed by the similarity in the protein profiles of the erythrocyte membrane antigens immunoblotted with rabbit antiserum to dog erythrocyte membrane antigens and infected dog serum. These results suggest the production of anti-erythrocyte membrane antibodies was induced by B. gibsoni infection.  相似文献   
127.
Eight Friesian cross cows three months pregnant to a single Friesian bull were immunised against East Coast fever by infection with Theileria parva (Muguga) sporozoite stabilate and treatment with pyrrolidino-methyl tetracycline. They were challenged with the homologous stock four times before calving and a fifth time after calving, and resisted all five challenges which killed all of the five groups of five susceptible controls. Calves born to these hyperimmunised dams were fully susceptible on challenge with the same stabilate, as were susceptible cows from the same farm and their calves. In both instances the calves died three to seven days earlier than the cows which were approximately 10 times heavier. These results show that one- to two-month-old taurine calves from artificially immunised dams are not protected from experimental T parva sporozoite challenge and that there is no inherent calfhood resistance to East Coast fever.  相似文献   
128.
Six dogs with laryngeal paralysis had clinical, electrophysiologic, and pathologic evidence of a more generalized polyneuropathy. Three of the dogs were young Dalmatians, one was a young Bouvier des Flandres, and two were older, large-breed dogs. The results of this study suggest that laryngeal paralysis in dogs may frequently be one clinical sign of an underlying, more generalized polyneuropathy. Two forms of this generalized polyneuropathy may exist: an early form, as seen in young dogs with congenital or hereditary disease, and a delayed-onset form that is usually found in older dogs with so-called idiopathic laryngeal paralysis, some of which may have hypothyroidism.  相似文献   
129.
Fingerling red tilapia ( Oreochromis mossambicus ± O. niloticus ) were orally administered 17-α-methyltestosterone (MT) under a warmwater (27.0 ± 0.5 C) and coolwater (21.5 ± 0.5 C) thermal regime. In the warmwater experiment, fish received either 0, 1, 5, 10, 30, 60, or 100 mg MT/kg feed for 75 days. In the coolwater experiment, fish received 0, 10, or 60 mg MT/kg feed for 75 days followed by a 34 day withdrawal period. After 75 days, fish receiving 60 mg MT/kg feed (best treatment) in the warmwater and coolwater experiments exhibited significantly higher growth rates than controls by 35.3 and 45.8%, respectively. Likewise, feed conversion among groups receiving 60 mg MT/kg feed in the warmwater and coolwater experiments were significantly better than the controls (1.14 versus 1.30 and 1.44 versus 1.77, respectively). During the withdrawal period, no significant differences in growth rates or feed conversion were observed between the control and treatment groups. MT treatment significantly affected the body composition (whole body and empty carcass) of the red tilapia in both experiments, elevating percent moisture and protein values, but depressing percent fat values. Results demonstrated that incorporation of MT into fingerling diets offers potential for extending the period when tilapias actively feed and grow in temperate climates.  相似文献   
130.
Tuberculosis in wild seals and characterisation of the seal bacillus   总被引:3,自引:0,他引:3  
SUMMARY Tuberculosis was diagnosed in 3 otariid seals found dead on beaches at 3 locations on the south coast of Western Australian between May 1990 and March 1991. This confirms that tuberculosis is present in the 2 native seals (Neophoca cinerea and Arctocephalus forsteri) in Western Australian waters. Mycobacterium sp isolated from the lungs of 2 of the seals were studied to determine the similarity of the strains to each other, to the strains isolated during 1986 from Australian sea lions and New Zealand fur seals kept in captivity at a marine park near Perth, Western Australia, and to a strain isolated in 1988 from a seal trainer who worked with the infected captive seals for 3 years. After restriction endonuclease analysis (REA) with the endonucleases Bst Ell, Bcl I and Pvu II, one of the wild seal strains appeared to have identical DNA fragment patterns to the strains from the captive seals and the seal trainer. The other wild seal isolate had identical REA profiles using Bst EII and Bcl I, but a minor difference was detected using Pvu II. Differences in these isolates were more clearly seen in restriction fragment length polymorphisms after hybridisation with two DNA probes. The secretory protein MPB70, present in M bovis, was not detected in wild seal isolates using sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blotting techniques. Analysis of protein and DNA fragment profiles indicated that seal tuberculosis isolates form a unique cluster within the M tuberculosis complex.  相似文献   
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