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1.
The present study was conducted to investigate the effect of feeding Camelina sativa to layer birds on egg production, egg quality characteristics, egg lipids, and fatty acid and lipid oxidation products. Fifty-eight-week-old ISA Brown Leghorn laying hens (n = 48) were kept in individual cages and were fed a corn- and soybean meal-based diet with added Camelina meal at 0%, (control), 5%, (CAM5), 10% (CAM10), and 15% (CAM15). The experimental diets were fed for a period of 80 d. Hen-day egg production was lowest for CAM15 (P < 0.05). A significant reduction in yolk weight was observed for CAM10 and CAM15 eggs when compared with control eggs (P < 0.05). Yolk weight, as a percentage of egg weight, was lower for CAM10 and CAM15 eggs, whereas albumen weight, as a percentage of egg weight, was higher in CAM10 and CAM15 eggs than in control eggs (P < 0.05). The yolk:albumen ratio was higher in control eggs than in CAM10 and CAM15 eggs (P < 0.05). Egg total fat content was lowest for CAM15 eggs and was 31.5, 31.9, 30.8, and 29.5 for control, CAM5, CAM10, and CAM15 eggs, respectively (P < 0.05). Total n-3 fatty acids constituted 0.32% in control eggs compared with 2.54, 2.69, and 2.99% in CAM5, CAM10, and CAM15 eggs (P < 0.05). An 8-fold increase in docosahexaenoic acid was observed in CAM15 eggs when compared with control eggs (P < 0.05). The n-6:n-3 ratio was 14.8, 5.6, 4.6, and 4.3 for control, CAM5, CAM10, and CAM15 eggs, respectively (P < 0.05). Total saturated fats were lowest for CAM5 and CAM10 eggs. Eggs from the CAM15 regimen had higher TBA-reactive substance values (P < 0.05) than those from the CAM5, CAM10, or control regimen. Camelina meal could be incorporated into poultry rations as a source of energy, protein, and essential n-3 and n-6 fatty acids. However, inclusion of more than 10% Camelina meal in the hen diet may affect egg lipid quality aspects. Therefore, measures for minimizing lipid peroxidation should be used to enhance egg quality and lipid stability.  相似文献   
2.
Fifty-one treponemas were isolated from pigs. Twenty-three isolates with typical morphology and growth characteristic were beta hemolytic, enteropathogenic, produced indole and with exception of three strains did not ferment fructose. These strains were classified as typical T. hyodysenteriae and were usually isolated from pigs with symptoms of mucohemorrhagic diarrhoea. The seventeen other isolates were weakly beta hemolytic after 48 h incubation, enteropathogenic, 12 out of 17 produced indole, 10 out 17 fermented fructose. These strains were usually isolated from pigs with symptoms of gray-green diarrhoea and classified as T. hyodysenteriae 2 biotype or intermediate type. They may be compared with Treponema sp. isolated by Taylor et al. Eleven non enteropathogenic strains showed typical characteristic for T. innocens. Gas chromatography analysis of the fatty acids production from glucose, showed that all isolated treponemas produced acetate and butyrate. Typical T. hyodysenteriae produced additionally propionate. Strains of T. hyodysenteriae biotype 2 produced propionate or isobutyrate as well.  相似文献   
3.
以北京白鸡Ⅲ系七世代选择群和基础群为材料,估计选择产蛋量七个世代对蛋壳及蛋品质产生的相关反应.结果表明,经七个世代选择,产蛋量、蛋重、蛋白高度和哈夫单位都有所提高,而蛋壳厚度和蛋比重有一定程度下降.估计蛋壳厚度、蛋白高度和哈夫单位的遗传力分别是0.159 5、0.017 8和0.099 4.产蛋量与蛋白高度、哈夫单位和蛋壳厚度呈负遗传相关.选择产蛋量使蛋壳品质发生负向相关反应.  相似文献   
4.
This experiment was conducted to study the albumen quality of eggs from 60-wk-old hens fed 0 or 10 ppm supplemental vanadium (V) as influenced by storage conditions and length of storage time as well as the effect of V feeding and withdrawal on albumen quality over time. After hens were fed V for 23 d, eggs were collected and stored in the laying house at ambient temperature or in a cooler (15.5°C, 60% relative humidity) for 1, 3, 5, or 7 d. Eggs were then broken, and Haugh units (HU) were calculated. Hens fed V had poorer albumen quality than eggs from birds fed the control diet (62.5 vs. 72.1 HU, respectively). Eggs stored in the layer house had poorer albumen quality than those stored in the cooler (63.9 vs. 70.7 HU, respectively). Increasing storage time also had a detrimental effect on albumen quality. Quality declined more rapidly in eggs stored at ambient temperature than in the cooler, but it was not influenced by dietary V. Thus, there was no 3-way interaction as hypothesized.After 7 d of feeding hens 10 ppm V, their eggs had poorer albumen quality than eggs from hens fed the control diet. Time analysis indicated that the significant negative effect to albumen quality occurred in V-fed hens on d 1, 2, 5, and 12 of supplementation. When these hens were then switched to the control diet after 30 d of V supplementation, albumen quality continued to decline for 2 d but did not differ by d 6 from that of eggs from hens given the control diet.  相似文献   
5.
粗酶制剂在大麦日粮中对产蛋鸡的影响   总被引:3,自引:0,他引:3  
就粗酶制剂在大麦日粮中对产蛋鸡产蛋性能的影响进行了两次试验。按0.1%比例的酶制剂添加于含大麦28.5%和50%的日粮中,分别饲喂330和242日龄的产蛋鸡。结果添加酶制剂对鸡产蛋率无明显提高,而对每个蛋重和鸡蛋质量有所改善,同时使产蛋鸡外周血液中促甲状腺激素和生长激素显著提高,而使甲状腺素显著降低。  相似文献   
6.
Bacterial peptidoglycans and the synthetic analog muramyl dipeptide possess various immunomodulating properties (adjuvant effect, increase of resistance to infectious agents and to tumor growth). They are able to induce B cell activation and to stimulate macrophages to produce monokines such as Interleukin 1 (IL 1). IL 1 plays an essential role in immune response. It promotes thymocytes maturation and Interleukin 2 secretion by antigen sensitive T cells, which in turn triggers regulatory T cells. Moreover, it is involved in the proliferation and differentiation of B cells.

There is a correlation between the immunoenhancing effect of PG of a definite structure and their ability to induce IL 1 secretion. Non-adjuvant PG were inactive. This suggests that one of the major mechanisms of action of adjuvant PG could be the stimulation of IL 1 synthesis.  相似文献   

7.
In this paper, we estimate the costs and benefits of implementing the proposed National Organic Program for laying hens compared with alternatives. For the regulatory proposals under option 2, the regulatory cost will be zero because most producers are already in compliance with the proposed regulation. The anticipated benefits of this regulation will be zero as well, because the current market prices already reflect consumers’ willingness to pay for the existing animal welfare conditions. For the regulatory proposals under option 3, before market adjustments, the average regulatory burden for the entire organic egg industry will amount to $0.09 per dozen eggs, with extreme variations between $0 for small operations and $2.30 per dozen for large operations. If we rely on the average price of organic eggs, $2.69 per dozen, and assume a maximum estimated benefit associated with improved animal welfare conditions, that consumers would be willing to pay of about 30% above the current market price, the estimated benefit of regulation amounts to $0.81 per dozen eggs. Based on the findings, we conclude that option 2 is welfare neutral and could be easily adopted because it already has been adopted by representative producers. For option 3, the benefit-cost ratio is larger than 1, which indicates that the proposal passes the benefit-cost ratio test. The obtained result, however, has to be interpreted with serious reservation because of the differential effect that the proposed regulation would have on different industry participants. Under option 3, the effect of the proposed changes on small organic egg producers is negligible because most small producers are operating under conditions similar to the proposed living standards. However, costs will increase substantially for large organic egg producers and likely cause a substantial number of producers to exit organic production and switch to conventional production, which would cause a substantial decline in the prices of conventional eggs and organic feed in the short run.  相似文献   
8.
A review of the recent and/or significant literature concerning Corynebacterium equi, including its morphologic, biochemical, immunological, and pathological characteristics in the foal, humans and other animals is presented. The similarity in the tissue responses of mammalian hosts to C. equi and Mycobacterium spp. is discussed.

The antigenic structure and virulence factors associated with C. equi. other corynebacteria and mycobacteria are compared.

The immunological aspects of resistance to C. equi are considered. The evidence suggests that the major immune response elicited in the foal by C. equi is cell-mediated. However, the immunopathogenic mechanism needs clarification. Areas of future research are suggested.  相似文献   

9.
建立了测定中兽药口服液中170种隐性药物的超高效液相色谱—四极杆静电场轨道阱质谱( HPLC- Q-Exactive Focus/MS) 高通量筛查方法。通过构建药物筛查数据库并与样品中未知物信息进行比对,从而实现快速筛查中兽药口服液中隐性药物的种类和含量。数据库包括磺胺类、喹诺酮类、β-受体激动剂类、硝基咪唑类、苯并咪唑类、蛋白同化激素类、糖皮质激素类、喹噁啉类、四环素类、抗病毒类、酰胺醇类和真菌毒素类等12类170种药物的筛查参数。样品中人为添加化学药物,经1%甲酸乙腈提取,QuEChERs净化,氮气吹干,0.2%甲酸水复溶上机,正负模式扫描,TraceFinder软件筛查定性,当药物添加浓度为400ng/g时,170种添加药物的检出率约为92.8%,随着药物浓度逐步提高至1 μg/g时,所有添加药物均可检出。结果表明,该方法可满足中兽药口服液中隐性药物高通量快速筛查的需要,为打击畜禽养殖投入品中非法使用化学药物的行为提高技术支持和数据支撑。  相似文献   
10.
The chemoprophylactic efficacy of a single dose of the 10% long acting (LA) injectable formulation of moxidectin on nematode infections in calves, was evaluated. Two similar groups of 11 female, first grazing season Holstein calves were turned out in early May on separate plots of a single, naturally infected pasture. Until 56 days post-treatment (pt), the percentage reduction in faecal egg output was 100%, remaining above 90% during the entire trial, except for day 126 pt. More than 90% of the larvae in the treated group were identified as Cooperia until 140 days after treatment and more than 70% during the rest of the trial, whereas in the control group Cooperia was the most abundant species until day 84 pt and Ostertagia from 126 days pt onwards. The reduction in faecal egg output in the treated group was reflected in the mean pepsinogen levels being below the pathogenic threshold at the end of the grazing season (1.8 units of tysrosine (U tyr)) and the absence of diarrhoea during the second half of the grazing season. In the control group pepsinogen levels remained high (mean: 5.5 U tyr) and prolonged diarrhoea occurred in the second half of the grazing season. Furthermore, the weight gain for the treated group at the end of the grazing season was 41.9 kg higher than for the control group. At necropsy, the reduction in O. ostertagi worm burden in the treated group was 97.5% compared to the control group, while the reduction in C. oncophora worm burden was 57%. An additional benefit of the long acting parasitological control, was reduced pasture contamination.  相似文献   
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