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51.
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This study describes the epidemiological features of bovine spongiform encephalopathy (BSE) in Northern Ireland where the first case occurred in November 1988. They were very similar to those observed in Great Britain except that the annual incidence of BSE in 1990 in Northern Ireland, 2.3 confirmed cases per 10,000 adult cows, was approximately one 10th of that in Great Britain. The findings were also consistent with the current hypothesis that affected cattle had been exposed to a scrapie-like agent via cattle feedstuffs containing ruminant-derived protein. However, a preliminary investigation of the potential sources of infection for cattle in Northern Ireland did not provide any conclusive evidence.  相似文献   
53.
1,268 sera collected from slaughtered pigs in Hassia (FRG) from 1986 to 1988 were tested for antibodies against porcine and human influenza A virus strains using the single radial haemolysis test (SRHT). Antibodies against the porcine strains (subtype H1N1) A/Swine/Arnsberg/1/81, A/Swine/Iowa/15/30 and A/New Jersey/7/76 were detected in 411 (32.4%), 318 (25.1%) and 304 (24.0%) of sera, respectively. Up to 1988 a slight increase (10%) in the seroprevalence to A/Swine/Arnsberg/1/81 was noticed, whereas the results obtained with the other strains showed little variation. Antibodies against the human H1N1 strain A/Singapore/6/86 were only found in sera collected 1987 and 1988 in rates of 1.6% and 3.0%. Serological indication of infections with the human H3N2 strains A/Victoria/1/75, A/Hong Kong/1/68 and A/Philippines/2/82 could be shown in 286 (22.6%), 178 (14.4%) and 135 (10.6%) of the serum samples. Within the three year period the rate of sera positive for antibodies against A/Philippines/2/82 increased from 6.5% to 23.0%, whereas no variation in the rates were found using the other H3N2 strains. Antibodies simultaneously against porcine (H1N1) and human (H3N2) virus strains were detected in 9.9% of all sera tested.  相似文献   
54.
Linear functions of body weight and condition score at weaning and 18 mo of age were used to predict the mature weight (A) and maturing rate (k) parameters of an asymptotic growth model of Angus cows at the Subtropical Agricultural Research Station, Brooksville, FL. From 1981 through 1988 a heavy-mature-weight line (Line A) and a rapid-maturing line (Line K) were selected based on predicted A and k values. Linear contrasts (A-K) of least squares means for weight at fixed ages indicated that the weight difference between lines increased from birth to maturity during the period of the study. Animals from Line A were heavier (P less than .01) at all ages. A negative response in maternal ability, relative to increased growth potential of their calves, seems to have occurred in the cows of Line A. Mature weight was reached at approximately 4.5 yr of age in Line K and at approximately 5.5 yr in Line A. Brody's three-parameter and Richards' four-parameter functions were fitted to 2,855 quarterly weights of cows, from birth to 6.5 yr of age, to estimate the average growth curve for each line. Brody's model gave better estimates of weights from 18 mo to maturity, but the asymptotic residual mean squares were slightly higher because early weights were overestimated. Linear and nonlinear regression analyses of weight-age data and comparisons of degree of maturity at different premature ages showed differences in the growth patterns of the two lines selected for early predicted values of A and k.  相似文献   
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Serum progesterone concentrations and alkaline phosphatase (ALP) activity of blood neutrophils were determined in 3 groups of cows (n = 5 each) on days 1 and 2 and then at 3-day intervals up to 32 days post-partum. Group I cows had a normal delivery, Group II cows had dexamethasone-induced parturition and Group III cows were subjected to a caesarian section. All cows in Group III and 2 cows in Group II retained their fetal membranes. Mean serum progesterone concentrations declined the second day after calving (to < 0.67 ng/ml) and remained at low levels (< 0.54 ng/ml) throughout the observation period, except for the values in Group III, which were elevated on day 16 (0.94 ng/ml), declined again on day 26 (0.46 ng/ml) and peaked (1.05 ng/ml) on day 32 portpartum. Significant (P < 0.01) differences were found between serum progesterone concentrations on day 1 and on each of the other sampling days in Groups I and III. Day X parturition group interaction was significant (P < 0.05) for the progesterone concentrations. No significant differences were found between the overall means of ALP activity of blood neutrophils in the 3 parturition groups nor between days of the experiment. No significant correlation was found between serum progesterone concentrations and ALP activity values of blood PMN during the first 32 days post-partum. Inhalt: Serum Progesteron Konzentrat und Aktivität der alkalischen Phosphatase in neutrophilen Blutzellen bei Küken mit normalem und abnormalen Geburtsverlauf Serum-Progesteronkonzentrationen und alkalische Phosphatase- (ALP) Aktivität von neutrophilen Granulozysten, nach der Abkalbung am Tag 1 und 2 und dann im Abstand von 3 Tagen bis zum 32. Tag p.p. bei Kühen untersucht, die in drei Untersuchungsgruppen (n = 5) eingeteilt waren. Gruppe I kalbte normal ab, in Gruppe II wurde die Geburt durch Dexamethason eingeleitet, und Kälber der Gruppe III wurden via Kaiserschnitt gewonnen. Alle Tiere der Gruppe III und 2 Kühe der Gruppe II wiesen Nachgeburtsverhaltungen auf Der mittlere Serum-Progesterongehalt sank am 2. Tag p.p. auf < 0,67 ng/ml ab und blieb auf niederigem Niveau (< 0,54 ng/ml) während der gesamten Untersuchungs-periode. Lediglich in Gruppe III, mit erhöhten Werten (0,94 ng/ml) an Tag 16 p.p., sanken die Werte wieder an Tag 26 p.p. (0,46 ng/ml) und erreichten einen Maximalwert an Tag 32 p.p. mit 1,05 ng/ml. Signifikante (P 0,01) Unterschiede in der Serum-Progesteronkonrentration wurden zwischen Tag 1 p.p. und allen anderen Untersuchungstagen in den Gruppen I und III gefunden. Interaktionen zwischen den Gruppen für Tag X waren signifikant (P 0,05). Keine signifikanten Unterschiede wurden für den Gesamtmittelwert der ALP-Aktivität in den neutrophilen Granulorysten zwischen den Gruppen und im Vergleich der Untersuchungstage gefunden. Es wurden auch keine signifikanten Korrelationen zwischen den Serum-Progesteronkonzentrationen und der ALP-Aktivität der PMN während der ersten 32 Tage p.p. nachgewiesen.  相似文献   
57.
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   
58.
The impact and relevance of dentistry in a general feline practice is detailed. Hospital policy and protocol are described for client education, preanesthetic evaluation, dental procedures, and recall programs. A discussion of commonly observed feline dental problems is included.  相似文献   
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60.
The paper gives an overview of the history of the school of vet. med. technicians at the School of Veterinary medicine Hannover.  相似文献   
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