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161.
Utilization of soybean meal as an alternative protein source in the Mediterranean yellowtail, Seriola dumerili 总被引:1,自引:0,他引:1
A. TOMÁS F. DE LA GÁNDARA A. GARCÍA-GOMEZ L. PÉREZ & M. JOVER 《Aquaculture Nutrition》2005,11(5):333-340
The availability of defatted soybean meal as a substitute for fish meal was evaluated in juvenile (450 g on average) yellowtail fed diets containing several levels of soybean meal (from 20 to 50%). After 153 days, liveweight averages were 980, 925, 795 and 670 g for fish fed diets in which fish meal was partially substituted with 20, 30, 40 and 50% soybean meal, and feed conversion ratios were 2.79, 3.09, 4.57 and 6.52, respectively. Regression analysis showed a negative effect of inclusion of soybean, although fish fed diets containing 20% and 30% of soybean did not present statistical differences and grew significantly more, and had a better feed conversion ratio, than fish fed 40 or 50% diets. Likewise, muscle protein level was lower and lipid content was higher in fish fed 20 or 30% soybean. No differences were obtained for protein digestibility coefficients of experimental diets. 相似文献
162.
海西地区指州辖天峻县、乌兰县、都兰县、德令哈市、格尔木市以及西部大柴旦、冷湖、茫崖三镇,覆含柴达木盆地。畜牧业是海西州支柱产业之一,草地是其发展的基础,畜牧业发展需要人工草地生产支持,科学布局人工草地对于安全高效发展草地畜牧业具有积极重要的现实意义。 相似文献
163.
为了推广与发展麦后移栽棉种植模式,在大田条件下,研究了工厂化两苗互作育苗麦后机械化移栽棉花的生长发育及产量特点.结果表明:营养钵育苗麦后移栽春棉、工厂化两苗互作育苗麦后移栽春棉和夏棉的子棉产量和霜前子棉产量相当.与麦套移栽春棉相比,麦后移栽棉花的生育进程有所推迟,子棉产量降低4.2%~4.7%,霜前花率降低0.9~1.3个百分点;但与麦后直播夏棉相比,麦后移栽棉花显著增产57.3%~58.2%,霜前花率提高约19个百分点;与麦后直播春棉相比,麦后移栽棉花显著增产62.1%~63.0%,霜前花率提高约20个百分点.此外,棉花麦后移栽,有利于小麦全幅播种和机械收获,且小麦产量比套种田小麦增产25%以上(P<0.05),同时,棉花工厂化两苗互作育苗实现了专业化、商业化和规模化育苗,有利于棉花机械移栽.可见,工厂化两苗互作育苗麦后机械化移栽春棉和夏棉可以取代传统营养钵育苗麦后移栽. 相似文献
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165.
An ELISA for the detection of anergic tuberculous cattle 总被引:6,自引:0,他引:6
P. PLACKETT J. RIPPER LA. CORNER K. SMALL† K. de. WITTE† L. MELVILLE† S. HIDES‡ PR. WOOD 《Australian veterinary journal》1989,66(1):15-19
An enzyme-linked immunosorbent assay (ELISA) for bovine antibody to antigens in unheated Mycobacterium bovis culture filtrate was standardised against a reference serum from an experimentally infected cow. Two Northern Territory herds with a total of 561 cattle were tested. All cattle reacting in the caudal fold tuberculin test, those giving strong reactions in the ELISA and those with visible lesions of tuberculosis were subjected to a detailed bacteriological examination. Of the 19 cattle which yielded isolates of M. bovis, only 4 were positive to the tuberculin test. Serum samples from 5 cattle gave ELISA values greater than 7.0 units. None of these 5 reacted in the tuberculin-test and 2 had no visible lesions. Of the 10 remaining cattle from which M. bovis was isolated, 3 had ELISA values between 6.5 and 7.0 units and were also without visible lesions. The ELISA values for the remaining 7 infected cattle ranged down to 4.6 units. Forty cattle yielded no M. bovis on culture of their tissues. They included 7 which were reactors in the tuberculin test and 23 with ELISA values of 7.0 units or more. The evident low specificity and sensitivity of the ELISA make it of little value as an alternative to the tuberculin test, but it can detect some anergic cattle at the cost of increasing the number of false positive reactors. This may be acceptable in some circumstances and would justify the use of the ELISA as a complement to the tuberculin test or to an in vitro assay of T-cell immunity. In the 2 Northern Territory herds described, the removal of 5 of the anergic cattle would have required a cull of 28 animals of 5% of the total. A cut off value of 6.5 units would have eliminated 3 more, but at the cost of culling 80 animals or nearly 15% of the cattle. Even so, 7 cattle from which M. bovis was isolated would have remained undetected by either test. 相似文献
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169.
The mechanism whereby Iinuron changes the functional and structural characteristics of chloroplast membranes was studied. The primary effect of the herbicide, the inhibition of phoiosynihetic electron transport results in an immuediatecessa-tion of carbon dioxide fixation and alterations in the membrane energization. These are accompanied by secondary processes contributing to phytotoxicity. The fundamental action in its phytotoxicity, as shown in a model system of isolated chloro-plasts, is the peroxidaiive breakdown of the polyunsaturated membrane lipids. This leads to destruction of the pigments, changes in the energy transfer, disorganization of the chloro-plast membranes, and accumulation of toxic organic peroxides. 相似文献
170.
Alexandra G. Collins-Webb DVM Deborah LA. Chong BVSc Stacy D. Cooley DVM 《Veterinary radiology & ultrasound》2023,64(2):345-350
Ultrasonographic intestinal muscularis thickening has not been described as an imaging feature of canine inflammatory bowel disease. In this retrospective case series, patients were identified by searching sonographic reports for “muscularis” and/or “muscular layer.” Patients were included if small intestinal muscularis thickening was reported, and sonographic images and histopathological samples of the small intestine were available for review. Cases with small intestines nodules, masses, or complete loss of wall layering were excluded. Sonographic images were retrospectively evaluated for jejunal muscularis layer thickness, and ratios of intestinal layer measurements were performed. Histological samples were retrospectively reviewed. Thirteen dogs met inclusion criteria: all dogs had sonographic intestinal muscularis thickening relative to the submucosa (>1.0, range of 1.3–2.5), and most dogs had muscular layer thickness above normal published ranges (11/13; all 13/13 above the weight-specific mean). More than half of the patients had overall normal wall thickness (11/13) and several had normal mucosal echogenicity (6/13). Therefore, in some dogs, the only sonographic abnormality in the small intestine was muscularis thickening. No dogs had lymphadenomegaly. Endoscopic partial-thickness (n = 11, duodenum and/or ileum) or surgical full-thickness (n = 2) samples confirmed inflammatory bowel disease. Direct comparison between jejunum sonographic characteristics and histology features was limited due to both partial thickness biopsies and lack of direct comparison between anatomical locations of ultrasonographic assessment and biopsy site. However, no cases that met the inclusion criteria had normal small intestinal histology. Comparable to cats, dogs with ultrasonographic intestinal muscularis thickening may have inflammatory bowel disease, and further workup for enteropathy is indicated. 相似文献