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A severe neurological disorder was observed during a very dry season, in sheep pasturing on land with mediterranean vegetation. During the crisis, lasting 5-20", ataxia and convulsions were the main clinical signs. Brain congestion, spongy appearance of the liver, interstitial nephritis and hyperpigmentation of visceral lymph nodes were the most important macroscopic lesions. Histopathological, histochemical and ultrastructural findings confirmed liver and kidney lesions and showed considerable neurovisceral storage of lipofuscin. Although further toxicological and experimental studies are needed to elucidate the origin of the disease, the Authors attribute the outbreak of the neurological syndrome to the ingestion of a neurotoxin containing plant.  相似文献   
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Blood samples were collected every 2 h during a 24 h period from 6 cows of one herd and 10 cows of another herd. In a third herd 9 cows were sampled every 2 h from 6 a.m. to 8 p.m. Concentrations of total bile acids, acetoacetate, glucose and free fatty acids were determined in blood plasma. A marked difference in individual bile acid concentrations and patterns of diurnal variation was found. For most cows the highest bile acid values were observed between 2 and 6 a.m. (overall mean (+/- SD) at 6 a.m.: 104 +/- 84 mumol/l, range: 20-307 mumol/l). Fourteen cows with a bile acid value greater than 90 mumol/l at 6 a.m. ("high BA") were characterized as a group by showing a pronounced decrease in the mean bile acid concentration after morning feeding. In the group of 11 cows with a 6 a.m. bile acid value less than 90 mumol/l ("low BA") the time of day did not contribute significantly to the bile acid variation. For the "high BA" group a nearly synchronous variation between the mean values of the 3 feeding dependent parameters (acetoacetate, glucose and free fatty acids) and the mean values of bile acids was found. The within animal coefficients of correlation between bile acids and the feeding dependent parameters were significantly higher in the "high BA" group than in the "low BA" group. No direct connection was found between bile acid levels and the quantity of concentrates fed or the individual milk yield.  相似文献   
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1. The incidence of exencephaly was investigated in chicken‐pheasant hybrids.

2. With the pheasant as sire, fertility was 7.lb6%, but with the fowl it was 19.lb5%; hatchability of fertile eggs, however, was similar, 42% and 41% respectively.

3. Only one exencephalic hybrid was obtained when the sire was the pheasant but 70 were noted when the fowl was sire. The incidence of this malformation in hatched chicks was 12 times more in crosses with the fowl as sire than in the reverse cross.

4. The frequency of exencephaly was greater with Rhode Island Red, Barred Leghorn or White Leghorn roosters than with Columbian Rock roosters.  相似文献   

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Testing issues     
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High electric fields have been used to extract organic cations from solutions of small organic molecules in polyphosphoric acid. The cations have been analyzed by mass spectrometry. Production of ions by this method is shown to be related to ease of protonation by acid rather than to ionization potential.  相似文献   
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Two experiments, using the ligated intestinal segment technique, were conducted to determine whether the pituitary hormone prolactin (PRL) could reduce Escherichia coli-induced fluid loss into the small intestine of 2- to 3-week-old pigs. Inoculation of 10(6) to 10(8) enteropathogenic E coli organisms into ligated jejunal segments caused a significant accumulation of luminal fluid within 12 hours. In the first experiment, intraluminal inoculation with 0.5 mg of ovine PRL along with the bacteria did not have any effect on fluid accumulation. Systemic IV treatment of the animals with 1.0 mg of ovine PRL at 3-hour intervals, beginning either immediately after or 9 to 10 hours before intestinal ligation, did not significantly (P less than 0.05) reduce fluid accumulation as compared with control animals. In the second experiment, IM administration of 100 microgram of thyrotropin-releasing hormone (TRH) at 3-hour intervals, beginning 6 hours before intestinal ligation, significantly (P less than 0.05) increased circulating PRL concentrations, as measured by radioimmunoassay. However, TRH treatment did not reduce the accumulation of luminal fluid in E coli-inoculated segments.  相似文献   
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