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141.
In a balance trial with 10 pigs (mean body mass 50 kg) the influence of a bacterial protein supplement (Alcaligenes eutrophus) on N-metabolism was investigated. The bacteria were included into the diet at levels of 7 and 14% at the expense of extracted soyabean meal. Thus bacterial "pure protein" (bacterial non-nucleic acid N X X 6.25) amounted to 30 and 60% of the protein of the ration. Consuming 2 kg of feed dry matter per day the animals of the control group (I) and the experimental groups (II and III) ingested 48 g, 52 g and 55 g of total N respectively. The difference in N-intake is explained by the additional nucleic acid-N, amounting to 19,8% of total bacterial N. Daily weight gain (on average 1054 g) and feed conversion efficiency (feed ingested/weight gain; on average 1,9) were relatively improved at the highest dietary level of bacterial cell mass. Faecal N-excretion was increased significantly, whereas renal N-excretion remained unchanged. Mean apparent N-digestibility was 87,4% showing no significant difference between the experimental groups. N-balance values were noticibly increased following the intake of the bacterial protein supplement. The excretion of urinary urea-N was slightly reduced whereas 4-6 times as much allantoin-N was excreted when bacteria were fed. It is calculated that about 80% of the bacterial purines are renally excreted as allantoin and uric acid. 相似文献
142.
The influence of genotypic differences in resistance to infection from Lymphoid Leukosis (LL) on mortality and egg production was studied in three pairs of sublines. One subline of each pair had been selected for resistance and the other for susceptibility to infection. At 10 months of age, almost no hens with neutralising antibodies against LL were found in the resistant sublines, while in each susceptible subline more than 40% of the hens had LL antibodies. At 21 months of age, very few hens of the resistant sublines had group-specific (gs) antigen in their eggs. Susceptible sublines differed considerably in this respect, from 81% gs antigen-positive hens in one subline to 9% or no positive hens in the others. On the whole, the susceptible sublines had 6% higher mortality during the laying period (8 months) but the size of the difference was influenced by vaccination against Marek's disease (MD) and varied considerably between pairs of sublines. Significant interactions between strain and genotype of resistance to LL infection were observed for mortality from "other causes" in hens vaccinated against MD, as well as for mortality from "Leukosis" and from "MD" in non-vaccinated hens. The average rate of lay from 1 to 8 months was 8% lower in susceptible hens. In the subline with the highest frequency of eggs containing LL group-specific antigen in the albumen, the reduction of laying rate was twice as large as in the other susceptible sublines. 相似文献
143.
Adetunji A Pascoe PJ McDonell WN Horney FD 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(9):342-346
A retrospective morbidity and mortality study was carried out on 125 case records of cattle involving xylazine/halothane anesthesia at the Ontario Veterinary College, Guelph between May 1979 and February 1983. 相似文献
144.
Barragry T 《New Zealand veterinary journal》1984,32(11):191-199
145.
The complement fixation test (CFT), the enzyme labelled immunosorbent assay (ELISA) and the gel diffusion precipitin test (GD) were compared, for the diagnosis of Brucella ovis infection in rams. The sensitivities of the tests in 109 rams which were shedding B. ovis in their semen were: CFT 96.3%; ELISA 97.2%; GD 91.7%. The specificities of the tests in 141 rams from non-infected flocks were: CFI 99.3%; ELISA 98.6%; GD 100%. Predictive values of the three tests were measured in 285 rams from infected flocks. Thirty-eight percent of these rams were shedding B. ovis in their semen. Predictive values of positive tests were: CFT 75.5%; ELISA 66.7%; GD 72.5%. Predictive values of negative tests were: CFI 97.1%; ELISA 97.6%; GD 93.8%. 相似文献
146.
The construction of a simple, portable restrainer for holding sheep in either the horizontal or vertical position for abdominal radiography is described. Examples of its use in locating slow-release pellets-and needles are given. 相似文献
147.
W R Hause 《Modern veterinary practice》1984,65(6):461-465
Pleural effusions can cause dyspnea and cyanosis, and are caused by cardiomyopathy, pyothorax, FIP, FeLV-related disease and trauma. Thoracentesis is used to obtain fluid samples for cytologic examination and culture. Radiographs made after thoracentesis may reveal the cause. Lymphosarcoma causes a sterile exudate containing neoplastic cells. Congestive cardiomyopathy causes a transudate or modified transudate. The sterile exudate of FIP has a proteinaceous background on cytologic examination. The exudate of pyothorax is septic. Treatment depends on the cause but generally includes thoracentesis and supportive care. Cardiomyopathy causes dyspnea, cyanosis, murmurs, gallop rhythms and other arrhythmias. Radiography reveals a globoid heart in the congestive form and a "valentine-shaped" heart in the hypertrophic form. Treatment of congestive cardiomyopathy involves use of furosemide, but is usually unrewarding. Hypertrophic cardiomyopathy is treated with propranolol. Fever may be caused by infection, immune-mediated disease, neoplasia and unknown causes. Treatment is aimed at removal of the underlying cause. 相似文献
148.
Roof WC 《Science (New York, N.Y.)》1984,223(4637):691
149.
150.
Teague WR 《New Zealand veterinary journal》1986,34(7):104-105
Of 32 calves given an unknown amount of a pluronic bloat mixture with their milk, 28 died in convulsions over 24 hours. Supportive therapy was unsuccessful. Concentrations of pluronic present in abomasal and rumenal contents supported a diagnosis of pluronic poisoning. 相似文献