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221.
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Day-old White Leghorn chicks deficient in selenium (Se) were fed a low Se basal diet (containing adequate level of vitamin E) for 2 weeks depletion period before they were given the experimental diets containing different levels of Se for 4 weeks. Dietary treatments contained 0.03, 0.06, 0.09 or 0.12 mg Se/kg as sodium selenite, barley, oats, meat meal or their extracted counterparts. Plasma GSH-Px activity was observed at weekly intervals, while the Se concentration of plasma and liver were determined at the end of the study. The biological availability of Se in the test ingredients was measured by the induction of plasma GSH-Px activity. In comparison to sodium selenite (100 %) it was: 77 % for barley, 80 % for extracted barley, 37 % for oats, 62 % for extracted oats, 20 % for meat meal, and 26 % for extracted meat meal. Using the retention of Se in plasma as a criterion, the following biological availability of Se was observed: barley 151 %; extracted barley 102 %; oats 90 %; extracted oats 107 %; meat meal 40 %; and extracted meat meal 47 %. Similarly, the efficiency of the test ingredients in increasing the Se concentration in liver was: barley 82 %; extracted barley 90 %; oats 67 %; extracted oats 98 %; meat meal 26 %; and extracted meat meal 31 %. The greater biopotency of the natural Se sources for increasing the Se concentration of the chick tissues than for inducing the plasma GSH-Px activity in comparison to sodium selenite, indicated that proportionally less amounts of the Se retained in the chick plasma from the natural sources were incorporated into the metabolic active form of Se, i.e., GSH-Px. Therefore, the plasma GSH-Px activity was suggested as the more reliable criterion to be used for the evaluation of the bioavailability of Se. 相似文献
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224.
Influence of dimethoate on testicular and epididymal organs, testosterone plasma level and their tissue residues in rats. 总被引:5,自引:0,他引:5
N A Afifi A Ramadan M I el-Aziz E E Saki 《DTW. Deutsche tier?rztliche Wochenschrift》1991,98(11):419-423
The effect of dimethoate at two dosage levels (6.25 and 12.50 mg/kg b. wt.) on male reproduction tissues and their tissue residues in rats were studied. The tested doses were given orally to male rats for 65 consecutive days. Sex organs weight analysis, semen picture, testosterone levels and histopathology of the male genital organs were the criteria used to evaluate the reproductive efficiency of the treated rats. There was a dose-related decrease in the weights of most genital organs and sperm motility associated with an increase in the percentages of dead and morphologically abnormal spermatozoa of treated rats. A decrease in plasma testosterone levels was observed in the treated groups. Histological examination revealed that dimethoate caused testicular lesions characterized by moderate to severe degenerative changes of spermatogonial cells and by partial arrest of spermatogenesis. Sections from liver revealed that the central veins and hepatic sinusoids appeared dilated, with some areas of haemorrhage. The highest concentrations from dimethoate were found in liver and tests and the lowest in skeletal muscle. Dimethoate and its metabolite analog were still present in a detectable concentration 21 days after stopping its oral administration. 相似文献
225.
S A Youssef A Ramadan N A Afifi M D Aziz 《DTW. Deutsche tier?rztliche Wochenschrift》1991,98(6):213-216
The effect of sodium taurocholate (S. T.) on the contractile response of rat-phrenic nerve diaphragm, frog's musculus rectus abdominis and frog's musculus gastrocnemius sciatic nerve preparation was studied. Moreover, interaction of S. T. with neuromuscular blockers are carried out, too. S. T. was found to have a dose-dependent reduction in the contractile response of the tested preparation. On the other hand, the inhibitory effect induced by S. T. did not block or alter the stimulatory effect of either acetylcholine or prostigmine. Trials were made to estimate the potency of S. T. in a comparison with other skeletal muscle relaxant drugs. In this respect S. T. exhibited a more potent effect than gallamine. In contrast, other skeletal muscle relaxants (dtubocurarine, atracurium, pancuronium and succinylcholine) were highly potent. There was also a marked synergistic effect between S. T. and other neuromuscular agents. 相似文献
226.
227.
The effect of stratification for 2–4 weeks and gibberellic acid (100 and 200 ppm) on germination of seeds and on total plant height was studied. The treatments resulted in earlier germination of seeds. The % germination was remarkably increased and stratification for 4 weeks followed by a 24-h soak in 100 ppm gibberellic acid solution gave the highest % germination.Total plant height was increased by the treatments and the effect was more profound when the seeds were stratified for 4 weeks followed by a 24-h soak in 200 ppm gibberellic acid solution. 相似文献
228.
A cross-sectional survey of ticks infesting sheep was conducted in Sennar State, Sudan. A total body collection of ticks was carried out at five localities Sennar town, Singa, Dinder, Abu Naama and Um Banein on two types of Desert sheep (Watish and Ashgar) on two farms at each locality at two monthly intervals for one year starting July 2002 to May 2003. Four tick genera and eight species were identified. They were Amblyomma lepidum, Hyalomma anatolicum anatolicum, Hyalomma truncatum, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus camicasi, Rhipicephalus evertsi evertsi, Rhipicephalus guilhoni and Rhipicephalus muhsamae. A significant (P < or = 0.05) seasonal pattern of activity was observed for A. lepidum and R. guilhoni with peak activity occurring during rainy seasons. The highest mean number of ticks (7.26 +/- 0.58) was recorded at Abu Naama, while the lowest mean (3.61 +/- 0.31) was recorded in Sennar. Watish type sheep carried significantly (P < or = 0.05) more ticks than Ashgar type. 相似文献
229.
230.
Journal of Plant Diseases and Protection - Food preferences and consumption parameters of Pieris brassicae larvae were carried out on 17 kale (Brassica oleracea var. acephala) genotypes.... 相似文献