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Wethers were fed complete granular feed rations including 41.81% of grass hay, 25.28% of barley, 15.37% of sawdust, 14.98% of molasses, 1.32% of urea, and 1.24% of mineral supplement in dry matter for 24 weeks. Samples of the dorsal rumen sac of these wethers were subjected to patho-anatomical, histological, histo-chemical, and electron-microscopical examination. Volatile fatty acids were also determined in the rumen fluid of slaughtered animals. The control group was given the same diet in the classical form with long hay. The rumen contents of the slaughtered animals of the experimental group had an increased level of total volatile fatty acids (125.93 mM) and butyric acid (17.8 M%). The acetate:propionate ratio was 3.66. No substantial differences were observed in enzymatic activity. Electronograms recorded an increase in the number of T cells and keratinizing cells -- this suggests an increased intensity of the process of keratinization.  相似文献   
13.
OBJECTIVES: To evaluate the effectiveness of transposition of the sacrotuberous ligament (LST) for the treatment of coxofemoral luxation in the dog. STUDY DESIGN: In vivo experimental study. SAMPLE POPULATION: Ten mixed-breed dogs (weighing 12 to 26 kg). METHODS: After general anesthesia, the LST was exposed and released from the sacrum with a sacral bone fragment. Coxofemoral luxation was created by capsulotomy and transection of the ligament of the head of the femur. Suture was passed through 2 small holes in the bone fragment to guide transposition of the LST through a tunnel drilled through the acetabulum and femoral head and neck. The suture material was pulled tight and an interference screw was placed into the femoral tunnel to lock the sacral bone fragment and LST securely in the tunnel. Butorphanol was administered for pain relief and dogs were allowed unrestricted activity. Coxofemoral radiographs were obtained at 15-day intervals. Two dogs were euthanatized for macroscopic and histopathologic examinations at 3 months. RESULTS: Release of the sacral bone was moderately difficult. The transposed ligament and bone fragment were of an appropriate length and were easily and securely fixed by a interference screw method. Visible severe lameness, during the first 7 to 10 days improved to mild lameness within 10 to 21 days. Gait was subjectively normal after 5 weeks. No radiographic abnormalities were observed at any time point. Grossly, the LST was intact and apparently viable and functional. On histopathology, the space in the bone tunnel was filled with new tissue and a hyaline-like layer surrounded the LST. The sacral bone fragment attached to the LST was united with the femoral bone. CONCLUSIONS: Transposition of the LST reduced and stabilized experimentally induced coxofemoral luxation in 10 dogs. Survival of the LST up to 3 months and its adaptation to transposition suggest that this surgical technique could be considered as a permanent treatment option for hip luxations. Transposition and fixation of the LST was easy, but releasing the sacral edge of the LST was difficult because of its deep location and division of the origin into 2 branches in some dogs. CLINICAL RELEVANCE: Results of this experimental study suggest that the technique may be satisfactorily used in dogs with coxofemoral luxation.  相似文献   
14.
A surgical technique is described for transposition of the sacrotuberous ligament to replace the teres ligament in the treatment of coxofemoral luxation in dogs. Ten dogs with coxofemoral luxation were treated using this technique and all animals regained full limb function within two months of surgery. It is suggested that the technique could be employed in dogs suffering from all types of hip luxations.  相似文献   
15.
An attempt was made to understand the molecular systematics and genetic differences between 10 original chrysanthemum cultivars and 11 mutants. The similarity among the cultivars and mutants varied from 0.17 to 0.90 using RAPD analyses, a simple but efficient method to distinguish cultivars and to assess parentage. Two distinct groups were found. Two cultivars were present as a separate group showing differences from all other cultivars. Mutants with different flower colour could be identified at the molecular level using RAPD technique holding promise to identify unique genes as SCAR markers. A high genetic distance among the different chrysanthemums showed that there exists a possibility of introgressing new and novel genes from the chrysanthemum gene pool.  相似文献   
16.
Tomato spotted wilt (TSW) disease is a serious constraint to tomato production in various regions of the world. The effect of TSW on tomato yield is largely influenced by time of infection. Early infection usually results in severe stunting of the seedling and even death of the plant. Plastic film mulches affect both the incidence of TSW, and plant growth and yield of tomato. The objective of the present study was to determine the effect of root zone temperature (RZT) as affected by plastic film mulch on the manifestation of symptoms of TSW, and growth and yield of tomato plants either artificially inoculated with tomato spotted wilt virus (TSWV) or under natural TSW infection. In artificially inoculated plants as well as in plants under natural TSW infection, vegetative top fresh weight (FW) and fruit FW both increased with the length of time after transplanting that the plants remained free from TSW symptoms. The root zone temperature was highest under black mulch (seasonal mean = 27.5 °C), followed by gray (27.0 °C), silver (25.8 °C), and white (24.8 °C) mulches. The plants grown on black mulch showed the earliest appearance of TSW symptoms, and had significantly reduced vegetative growth and fruit yields compared to plants on the other mulches. In conclusion, utilization of plastic mulches that created conditions of high RZT stress resulted in reduced plant growth and yield and predisposed the plants to earlier expression of TSW symptoms compared to plants grown at RZTs more favorable to tomato plant growth (optimal RZT = 26.1 °C [Díaz-Pérez, J.C., Batal, K.D., Granberry, D., Bertrand, D., Giddings, D., Pappu, H., 2003. Vegetative top growth and yield of tomato grown on plastic film mulches as affected by the appearance of symptoms of Tomato spotted wilt virus. HortScience 38, 395–399]). Since these plant responses to TSW under heat stress occurred in artificially inoculated plants as well as in plants under natural TSW infection, high RZTs probably affected the plants directly, independently of any possible effects on the thrips vectors.  相似文献   
17.
The rate of passage of experimental diets based on non-conventional feeds through the alimentary tract of rams was studied. The composition of diets was as follows: barley straw (D-2, D-1), conditioned beech sawdust (D-2, D-1), waste cellulose fibre (D-2, D-1), lactosylureide (D-2), peanut waste (D-2), urea (D-1), wood molasses (D-2, D-1) and mineral supplement (D-2, W-1). The control feed (K) contained straw, barley, beet molasses and mineral supplement. As a marker was used a single application (50 g) of polyethylene (PE), particle size 0.4 mm and specific weight 0.924, which formed 3.9, 3.5 and 4% of the diet dry matter. After 10 days the recovery of polyethylene amounting to 81.23% (D-2), 84.78% (D-1) and 86.6% (K) was established. The polyethylene losses occurred most probably at its administration in feed (10-12%), elapsing of polyethylene excreted after 10 days following the administration (0.5-1.5%) and by potential retention in rumen and large intestine. Maximal excretion of feces was observed during the second day after administration of the markered feed; after three days the excretion was as follows: group D-2-62%, group D-1-57% and control group 75.6%. A longer retention time in rumen at feeding D-2 and D-1 diets can be contributed to a high content of fibre in these diets. The digestibility of dry matter in diet D-2 amounted to 61.2%, i n diet D-1 to 62.3% and in control diet to 68.7%. Higher digestibility of feed is in accordance with its higher excreting. As shown by the results, the diets based on non-conventional feeds (secondary wood sources) lead to the prolongation of feed retention time in rumen and slow down the rate of passage through the alimentary tract.  相似文献   
18.
The analgesic activity of methanol extract of Cleome viscosa, given orally at the doses of 100, 200, 400 mg/kg was evaluated for its analgesic activity in mice using the acetic acid-induced writhing and the tail flick, tail clip, tail immersion methods. The extract showed promising activity in all the tests.  相似文献   
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20.
Guggal, a threatened species that is endemic to western India, is tapped to extract medicinally important oleo–gum–resin(guggul). However, the plant dies after gum exudation. The indigenous tapping techniques used by local people were examined in Gujarat, India to discover the scientific basis behind these techniques: selection of gum inducer, season of tapping, and plant parts to be tapped. First, the presence of Xanthomonas axonopodis pv. commiphorae(Xac) in the gum suspension used for tapping was established. This bacterium induces gum oozing from the tapped plants and later, causes them to die off. The population of Xac in gum was found to decrease with the age of the gum. With that, fresh gum increased the tapping success. Second, local people preferred tapping during the warm season, which we validated by determining that Xac growth was best at 30 °C. Tapping during September(mean temperature 25.7–30.0 °C) clearly favoured growth of the pathogen and yielded maximum guggul. Multiple tapping on a mature tree ensured maximum gum extraction before its death. Finally, application of indigenous technology under natural plant stands by the local people ensured availability of this important raw drug for consumption. Our study established that the age–old traditional methods have a strong scientific basis. However, it is imperative to formulate strategies based on contemporary scientific understanding to protect this natural resource before it becomes extinct.  相似文献   
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