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161.
In faeces and ileal digesta samples of 31 intact (INT) as well as 73 surgically differently prepared pigs bacterial fractionations and 2.6-diaminopimelic acid (DAP) estimations were carried out in order to calculate the bacterial N proportion in faeces N and digesta N after feeding various diets. Because of a high individual variability and the analytical variation width of the DAP/N-ratios no distinct influences of the fed diets could be found. The average DAP/N-values in the faeces (0.224) of INT pigs ranged in the same magnitude as in the digesta (0.0272) of ileorectostomized (IRA) pigs with open colon descendens (IRAo), where a digesta backflow is possible. Distinct lower DAP/N-ratios (0.0125 resp. 0.0043), however, were found in the digesta of pigs with ileo-caecal cannulae (IZB) or IRA pigs with closed colon (IRAg). On the base of various premises (N of the "bacterial fraction" C is only bacterial N; the DAP found in fraction A originates from intestinal bacteria adhering to feed particles) conducted calculations of the bacterial N proportions (in per cent of total N) led to the following data: Faeces of INT pigs: 43.0 ... 68.2 vs. 69.6 ... 89.0; digesta of operated pigs (except protein free diet) IRAo: 22.3 ... 57.0 vs. 46.2 ... 73.8; IZB: 17.0 ... 35.7 vs. 25.2 ... 53.6; IRAg (only 3 pigs): 23.6 vs. 24.2. The proportion of bacterial N in the digesta N of protein free fed IRAo pigs was 22.0 vs. 22.6%. 相似文献
162.
R Beza 《Archives of Animal Nutrition》1991,41(4):347-358
The experiment was conducted on 364 male Wistar rats of which 74 were included into the "zero" group and the remaining 290 were divided into 5 experimental groups, corresponding to the dietary protein levels of 4, 5, 10, 15 and 20%. The protein source in the diet was skim milk powder. The animals were fed individually and ad libitum. The experiment was performed between the 21 and 66 days of life of the rats and during this period, the animals in each group were successively killed to determine the nitrogen content in the body. Between the N content in the body and the body mass of rats from "zero" group, the relationship N0/W0 was determined. In each experimental group, two relationships were determined: --final nitrogen against final body mass--Nf/Wf --gain of nitrogen against gain of body mass--delta N/delta W. The derivatives of both functions were used for calculation of the daily gains of nitrogen (delta Nd) 1. According to the relationship Nf/Wf there was a similar significant increase of nitrogen content in the body in all groups with increasing the body mass, according to bc = 1.0413. The percentage of nitrogen in the body increased significantly only at dietary protein levels over 10%. 2. The rate of nitrogen gain in the gain of body mass according to delta N magnitude of was relatively constant in all groups (bc = 1). Thus, N-% in delta W was also relatively constant. N-% in the body gain increased significantly only at dietary protein levels over 10%. 3. Differences in the gains of nitrogen, as calculated by the derivative dNf/dWf and by d delta N/d delta W, showed in the first line in low-protein groups (on 4 and 5% protein) due to the error of estimation of the initial-N according to the equation N0 magnitude of W0. The mean relative error of estimation the initial-N was +/- 3% but in groups on 4 and 5% protein it charged the gain of N with 9-12% in spite of excluding from the relationship delta N magnitude of delta W rats with delta W less than 10 g. 4. Only when delta N greater than or equal to 1.3 g and delta W greater than or equal to 43, the error of estimation of delta N, did not exceed 3%.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
163.
164.
Crease R 《Science (New York, N.Y.)》1991,252(5012):1480-1482
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Lavoie JP Couture L Higgins R Laverty S 《The Canadian veterinary journal. La revue veterinaire canadienne》1991,32(5):292-294
Bacterial isolations were reviewed from equine trachea, guttural pouch, uterus, wounds, abscesses, blood, synovial fluid, and abdominal fluid submitted to the Clinical Bacteriology Laboratory of the School of Veterinary Medicine at the University of Montreal for aerobic bacterial culture from 1986 to 1988. Of the 733 samples submitted, 324 (44%) were positive for bacterial growth, and 233 antimicrobial sensitivity tests were performed. Seventy-six percent of all positive samples yielded one bacterial species and two were isolated from 22% of positive samples. Streptococcus zooepidemicus, Escherichia coli, and Actinobacillus spp. were isolated from 39%, 18%, and 15% of the samples, respectively.
Bacterial growth was most common from guttural pouches, wounds and abscesses, and transtracheal washes (TTW), but was less common from uterus, blood, abdominal fluid, and synovial fluids. Streptococcus zooepidemicus was the most common bacterium recovered from guttural pouches, TTW, uterus, and wounds and abscesses. Escherichia coli predominated in abdominal fluids, blood, and synovia. Bacterial sensitivities to common antimicrobials are presented.
相似文献168.
Six Friesian calves from a pedigree herd died or were killed within 1 week of birth because of progressive central nervous disease in which the only consistent lesion was cerebral oedema. The cause was citrullinaemia, resulting from an autosomally inherited dysfunction of the urea cycle enzyme arginosuccinate synthetase. Citrullinaemia was diagnosed by demonstrating markedly elevated concentrations of citrulline in the blood of one calf and in the cerebral spinal fluid of another. One of two sires used in the herd was a heterozygous carrier of the disease. Heterozygocity was demonstrated using a polymerase chain reaction/restriction endonuclease test designed to detect the genetic mutation that causes citrullinaemia in cattle. 相似文献
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