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141.
1. Wheat, triticale 131 or triticale 72‐S could replace up to half the maize in broiler diets without affecting performance. Replacing more of the maize on either an equal nitrogen basis or a weight basis adversely affected performance.
2. Triticale 72‐S appeared to be superior to triticale 131 as a direct replacement for maize, but both grains were inferior to maize as energy sources. 相似文献
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Influence of environment on adrenal cortical response to ACTH stimulation in clinically normal dogs.
G C Vial G H Stabenfeldt C E Franti G V Ling 《American journal of veterinary research》1979,40(7):919-921
Effect of testing environment on adrenal cortical responses to an injection of ACTH in clinically normal dogs was examined in three locations, presumably of increasing order of stress elicitation: in a home; veterinary hospital (VH), 4 hours in a cage; and VH, overnight in a cage. Basal cortisol (hydrocortisone) values for plasma were significantly lower (P less than 0.001) for the home group (1.8 microgram/dl) when compared with values for the VH, 4-hour cage (3.8 microgram/dl) or the VH, overnight cage (3.9 microgram/dl) groups. However, significant differences (P greater than 0.05) were not observed 2 hours after ACTH admininstration for the home group (13.7 microgram/dl); VH, 4-hour cage group (14.8 microgram/dl); or VH, overnight cage group (16.0 microgram/dl). Responses of individual dogs were consistent (P less than 0.005). The testing environment did not markedly affect results of adrenal cortical function tests for dogs when ACTH stimulation was utilized. The response of dogs to ACTH, as monitored by immunologic assay techniques (competitive protein-binding assay or radioimmunoassay), was consistent and was useful as a diagnostic aid for adrenal malfunction. 相似文献
145.
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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The life cycle of Moniezia expansa was studied experimentally using 10 species of oribatid mites as intermediate hosts. Four of them became infected, namely Scheloribates laevigatus (76.2%), Sch. latipes (70.8%), Liacarus coracinus (20%) and Platynothrus peltifer (1.1%). The last was found for the first time to serve as intermediate host of M. expansa in Czechoslovakia. The development of the cysticercoid of M. expansa in the oribatid mites at 28 degrees C and 85% relative humidity is completed within 27 days. At 18-20 degrees C and the same relative humidity the development lasts even 97 days. 相似文献
149.
Ultrastructure of the cuticle and pseudobursa of adult males of four species of Trichinella has been studied by SEM. T. nativa differs markedly from T. spiralis, T. nelsoni and Trichinella sp. in the form of the pseudobursa. Trichinella sp. differs only slightly from T. spiralis and T. nelsoni. The ultrastructure of the cuticle revealed no characters suitable for the differentiation of the taxons under study. 相似文献
150.
Ruttan VW 《Science (New York, N.Y.)》1982,216(4541):23-29
The considerations involved in defining appropriate roles for the public and private sectors in agricultural research are examined with respect to mechanization, plant variety, and insecticide research and development. It is concluded that the public sector should continue to give mechanization a low priority. Varietal improvement should remain a relatively high priority until the effects of plant variety protection legislation become more apparent. Simultaneous achievement of safety, environmental, and productivity objectives in insect pest control will require that the public sector play a larger role in research and development. 相似文献