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51.
干燥鸡胸肉宠物食品护色研究 《畜牧与饲料科学》2019,40(12):25-31
为研究干燥鸡胸肉宠物食品在生产和贮藏过程中的颜色变化,减少因颜色变化引起的产品质量问题,采用三因素二次通用旋转组合设计,研究二丁基羟基甲苯(BHT)、柠檬酸和焦亚硫酸钠3种抗氧化剂对干燥鸡胸肉干贮藏过程中颜色变化影响规律。结果表明,BHT的护色效果最好,焦亚硫酸钠的护色效果次之,柠檬酸的护色效果最差。复配试验结果表明,0.02% BHT、0.10%柠檬酸、0.05%焦亚硫酸钠的组合配方护色效果最好,可有效改善干燥鸡胸肉宠物食品在生产和贮藏过程中颜色变化问题。 相似文献
52.
David Risco Pilar Gonalves María Bravo Waldo García‐Jimnez Rosario Cerrato Javier Hermoso de Mendoza Pedro Fernndez‐Llario 《Journal of animal physiology and animal nutrition》2019,103(2):668-674
Vitamin D (VitD) is involved in important mammalian physiological mechanisms, such as Ca–P metabolism, bone development and immunological response. VitD deficiencies are frequently detected in domestic animals and related to various health problems (e.g., rickets, bone deformation). However, knowledge about the status of VitD in wildlife species, such as the wild boar, is scarce. The aims of this work were to explore VitD status in wild boar populations from mid‐western Spain and to elucidate the influence of daylight exposure and food supplementation in levels of VitD. Serum concentration of VitD (measured as 25‐hydroxivitaminD) was assessed in 276 wild boar from 27 game estates located in mid‐western Spain using a commercial ELISA kit. In 19 out of 27 estates, the staff supplied a specific VitD‐enriched food (2,000 UI/Kg) ad libitum throughout the year, while in the remaining estates (8), no food was supplied. Blood samples were extracted from hunted animals (198) between October and February of hunting seasons 2016/2017 and 2017/2018, and from live wild boar (78) that were captured, sampled and released (March–September of 2017). The percentage of animals with VitD deficiency (<20 ng/ml), VitD insufficiency (20–30 ng/ml) and VitD sufficiency (>30 ng/ml) was estimated, and the relationship of these levels to factors like sex, age and season was assessed using chi‐square tests. Furthermore, associations between daylight exposure and supplemental food with VitD levels were explored using linear models. Of the studied wild boar population, 82.2% showed a VitD deficiency or insufficiency. VitD deficiencies were more frequent in animals sampled in winter and spring. Furthermore, levels of VitD positively correlated with daylight exposure and supplemental food intake. Ad libitum supplementation with VitD‐enriched food was insufficient to prevent VitD deficiencies in wild boar from November to April, probably because food consumption is lower during this period. 相似文献
53.
成年黄山短尾猴春季昼间行为时间分配 总被引:1,自引:0,他引:1
2007年3~5月,采用焦点动物取样法对黄山野生猴谷YA1群黄山短尾猴成年个体行为时间分配进行系统观察.数据分析显示:黄山短尾猴成年个体日活动行为主要为休息(59.72%)、理毛(17.50%)和觅食(14.82%),其他行为如漫游(5.86%)、玩耍(0.04%)和其他(1.64%)时间花费较少,觅食高峰与投喂时间基本一致.老年组个体比成年组个体花费较多的时间用于休息(Z=-5.811,P<0.01)和理毛(Z=-4.913,P<0.01),较少时间漫游(Z=-3.989,P<0.01).雄性个体花费较多时间休息(Z=-3.577,P<0.01)而雌性个体花费大量时间进行理毛(Z=-3.134,P<0.01).哺乳期雌性漫游行为(Z=-2.9541,P<0.01)低于非哺乳期雌性个体,其他行为(Z=-2.9541,P<0.01)明显高于非哺乳期雌性,而觅食行为(Z=-0.1773,P>0.05)无显著差异性.结果表明人工投喂是导致其行为时间分配的主要原因. 相似文献
54.
55.
在过去较长的时间段里,一些畜牧养殖业为了追求规模和经济效益,选择以牺牲环境为代价的生产管理模式。该模式虽然在短期内可以达到明显成效,但其带来的环境污染、食品安全、价格持续走低等问题日益显现,对畜牧养殖业健康、可持续发展形成威胁和挑战。饲料与食品均为可食之物,两者无明显界定,如小麦、玉米等即可作为动物饲料,又可以作为食品,而且诸多食品又来源于动物组织以及蛋和奶。所以,饲料产业与环境、食品安全息息相关。为便于论述,笔者从畜牧养殖业的角度来对饲料产业的环保问题及解决对策做出分析,为有关企业、部门提供参考。 相似文献
56.
风险(risk)是由一种或多种危害因子而引发危害事件的一种可能性或概率。危害因子可能属于物理的、化学的、微生物的范畴,病原微生物中的细菌、病毒、寄生虫等都可成为引发危害事件的风险因子。评估某一因子是否对人或其他生物构成威胁以及所危害的程度显得至关重要。事实上,存在于环境中的危险因子及其多种可能的传播途径都会引发多种危害性事件。因此,要想充分了解并揭示由危害因子引发危害的概率,以及其随后对人类健康造成的危害并非易事。风险评估则是对不良结果或不期望事件发生几率进行描述及定量的系统过程,现已被视为一种用于揭示存在于环境中的各种危害及其对人类健康造成的影响的方法。论文主要对食源性寄生虫风险评估的方法进行全面阐述。 相似文献
57.
在我国养猪业面临产品安全和环境污染两大瓶颈的情势下,如何使所生产的猪肉食用卫生,所排粪污环境安全,纯天然、无污染、广效低毒、绿色环保的中兽医药学为破解这两大瓶颈提供了技术支撑。充分发挥我国传统的中兽医药技术的特色和优势,构建以中兽医药为主体的猪只康养技术供给体系,旨在集生产管理"适其天性"、所喂药料"无污染"、治疗药物"纯天然"、预防措施治"未病"、治疗方法"和谐调节"和四季保健"药饲同源"于一体的技术供给体系,从源头上破解这两大难题,从而实现猪只康养,环境安全,猪肉安康,凸显出中兽医药是猪只康养的最佳供给体系。 相似文献
58.
K. S. Venturini M. F. Sarcinelli M. A. Baller T. C. Putarov E. B. Malheiros A. C. Carciofi 《Journal of animal physiology and animal nutrition》2018,102(4):1077-1087
Soya bean protein concentrate (SPC) with two particle sizes were evaluated on extrusion parameters, kibble formation, digestibility and palatability of dog foods. Eight diets were extruded: PBM—control diet based on poultry by‐product meal (PBM); GM—a diet in which corn gluten meal (GM) replaced 45% of the diet protein; cSPC15%, cSPC30% and cSPC45%—diets in which SPC of coarse particle size (600 μm) replaced 15%, 30% and 45% of the diet protein; and sSPC15%, sSPC30% and sSPC45%—diets in which SPC of small particle size (200 μm) replaced 15%, 30% and 45% of the diet protein. The digestibility of nutrients was evaluated for the PBM, GM, cSPC45% and sSPC45% diets, using six dogs per food. The PBM, GM and cSPC45% diets were compared for palatability. Data were submitted for analysis of variance, and the means were compared by polynomial contrasts or Tukey's test (p < .05). The cSPC increased the specific mechanical energy (SME) application, extrusion temperature and pressure linearly, resulting in lower kibble density and higher expansion and starch gelatinization (SG) (p < .01). When comparing the PBM, GM, cSPC45% and sSPC45% diets, higher SME, extrusion temperature and pressure, SG and kibble expansion were verified for the cSPC45% diet (p < .05). The DM, fat and crude protein digestibility were similar among diets. Faecal pH, ammonia and lactate did not differ, demonstrating that the removal of oligosaccharides and soluble non‐starch polysaccharides of SPC produces an ingredient with mostly non‐fermentable fibre. Dogs preferred the PBM to the GM diet (p < .05), but consumed the PBM and cSPC45% foods equally. In conclusion, SPC exhibited good extrusion functionality, favouring kibble expansion and SG, with high digestibility, similar to that of PBM. The removal of soluble compounds from soya beans resulted in an ingredient with low fermentable fibre content, which did not alter faecal formation or characteristics. 相似文献
59.
Three rapid agglutination assays for the identification of Staphylococcus aureus Monostaph (Bionor A/S, Skien, Norway), Staphyslide-Test (BioMerieux, Lyon, France) and Staph-Rapid-Test (Roche, Basel, Switzerland), were compared. A total of 104 Gram-positive, catalase positive cocci were tested: Nineteen Staphylococcus reference strains comprising 15 spp. (4 strains were coagulase positive), and 7 Micrococcus reference strains comprising 4 spp.; 22 food isolates comprising 13 S. aureus, 8 coagulase positive Staphylococcus spp., and 1 Micrococcus sp.; 56 animal isolates comprising 11 S. aureus, 9 S. hyicus subsp. hyicus, 2 S. intermedius, 15 coagulase positive and 19 coagulase negative Staphylococcus spp. Totally 54 strains were coagulase positive. Considering agglutination of a coagulase positive strain as a correct identification, Monostaph, Staph-Rapid-Test, and Staphyslide-Test correctly identified 52 (96.3%), 47 (87.0%) and 48 (89.0%) of the coagulase positive staphylococci, respectively. Monostaph, Staph-Rapid-Test and Staphyslide-Test showed 1 (2.0%), 4 (8.0%) and 4 (8.0%) false positive reactions respectively. Monostaph, Staph-Rapid-Test and Staphyslide-Test gave 0 (0.0%), 6 (5.8%) and 7 (6.7%) non-interpretable reactions, respectively. Monostaph may be a good alternative to the tube-coagulase test for rapid and reliable identification of coagulase positive staphylococci from both food and veterinary sources. However, false negative reactions may occur with coagulase positive strains of S. hyicus subsp. hyicus and S. intermedius. 相似文献