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101.
为研究橄榄鲜食品种(系)的氨基酸组成和营养品质,试验以福州主栽的灵峰、闽清2号和清榄1号橄榄为材料进行氨基酸含量测定,并对其进行营养和品质风味评价。结果发现,灵峰的总氨基酸含量最高,达到20.078 mg.g–1,而清榄1号的必需氨基酸含量最均衡。在各类氨基酸中,谷氨酸和天门冬氨酸为3种橄榄鲜食品种(系)的主要氨基酸,苏氨酸和赖氨酸的含量相对过剩,而甲硫氨酸和半胱氨酸可能为第一限制氨基酸;在橄榄特征风味形成过程中,组氨酸、丙氨酸和赖氨酸均会影响鲜食橄榄甜味的形成,精氨酸对苦味的形成存在较高的贡献率,天门冬氨酸和谷氨酸的大量存在可能是其鲜味形成的重要原因之一。此外,灵峰的药用氨基酸组分含量最多,达到13.94 mg.g–1。研究认为,不同橄榄鲜食品种(系)的氨基酸营养和风味品质存在差异,而药用氨基酸可能是橄榄的重要功能成分之一。 相似文献
102.
王巧红 《畜牧兽医科学(电子版)》2021,(5):125-126
呼吸道疾病是目前威胁鸡养殖产业健康发展的一类重大动物疫病,呼吸道疾病的病原种类多种多样,且造成的临床症状大致相同,诊断难度较大,如果没有进行妥善有效的鉴别、诊断,易造成整体的治疗方案缺乏针对性,难以在短时间内控制病情,错过最佳的防控时期。鸡呼吸道疾病常常混合感染并发感染,2种以上的病原相互叠加表现的临床症状复杂,诊断难度更大。该文主要论述鸡呼吸道疾病的鉴别诊断和防治措施。 相似文献
103.
In this study the starch digestion rates in broiler chickens from 18 samples of 5 commonly used feed grains (sorghum, wheat, maize, barley, triticale) were determined. The methodology to determine starch digestion rates in poultry is detailed herein. Starch digestion rates were not significantly different (P = 0.128) across the 18 feed grains, which reflects the wide variations that were observed within a given feedstuff. Nevertheless, starch digestion rates in broiler chickens offered wheat-based diets were significantly more rapid by 56.0% (0.117 versus 0.075 min−1; P = 0.012) than their sorghum-based counterparts on the basis of a pair-wise comparison. In descending order, the following starch digestion rates were observed: wheat (0.117 min−1), barley (0.104 min−1), triticale (0.093 min−1), maize (0.086 min−1), sorghum (0.075 min−1). The implications of these findings are discussed as they almost certainly have implications for poultry nutrition and the development of reduced crude protein diets for broiler chickens. 相似文献
104.
文章主要是对我国的珠江三角洲地区的生鲜农产品冷链的物流方式进行探究,结合现在我国的生鲜农产品冷链运输技术的现状和发展前景进行大胆的预测,并提出我国的珠江三角洲地区的生鲜农产品冷链的运输技术的网络化的建议。 相似文献
105.
Kazuhisa Honda 《Animal Science Journal》2016,87(9):1090-1098
The regulatory mechanisms underlying food intake in chickens have been a focus of research in recent decades to improve production efficiency when raising chickens. Lines of evidence have revealed that a number of brain‐gut peptides function as a neurotransmitter or peripheral satiety hormone in the regulation of food intake both in mammals and chickens. Glucagon, a 29 amino acid peptide hormone, has long been known to play important roles in maintaining glucose homeostasis in mammals and birds. However, the glucagon gene encodes various peptides that are produced by tissue‐specific proglucagon processing: glucagon is produced in the pancreas, whereas oxyntomodulin (OXM), glucagon‐like peptide (GLP)‐1 and GLP‐2 are produced in the intestine and brain. Better understanding of the roles of these peptides in the regulation of energy homeostasis has led to various physiological roles being proposed in mammals. For example, GLP‐1 functions as an anorexigenic neurotransmitter in the brain and as a postprandial satiety hormone in the peripheral circulation. There is evidence that OXM and GLP‐2 also induce anorexia in mammals. Therefore, it is possible that the brain‐gut peptides OXM, GLP‐1 and GLP‐2 play physiological roles in the regulation of food intake in chickens. More recently, a novel GLP and its specific receptor were identified in the chicken brain. This review summarizes current knowledge about the role of glucagon‐related peptides in the regulation of food intake in chickens. 相似文献
106.
食品的温度监控是一种有效的保证食品安全及保持冷藏链完整的手段,对冷冻冷藏食品在低温流通过程中实行温度监控是非常有必要的。目前,我国冷藏运输中的温度管理情况并不乐观,消费者获得的货物通常不能达到预计的要求。要解决这一问题,必须要借助于时间-温度指示器等来对其整个运输过程进行温度监控。本文对温度立法的必然性和前景,温度监控的重要性、原理以及在冷藏运输中的应用作了较详尽的介绍,并列举了几种国外时间-温度指示器的工作原理。 相似文献
107.
在新消费升级的背景下,人们越来越注重消费品质量和感受,乳制品消费的新鲜化和休闲化是新消费时代的发展趋势。营养鲜活、口感轻柔的巴氏奶,在我国乳制品液态奶品类中成为新的消费增长点,各大乳品企业纷纷加码低温赛道抢占市场。本文基于大量的文献研究并结合消费市场趋势,从而确定探究新消费下的巴氏奶行业问题。从巴氏奶市场发展现状入手,集合巴氏奶在国家政府部门所发布的各项利好政策为发展背景优势。通过分析巴氏奶在乳品市场中的规模,发现其增速提高和占比增大的发展态势,强劲的增长吸引各大乳品企业争先布局低温市场。为了避免盲目入局,本文继续分析了巴氏奶在目前发展中存在的问题,并对上述巴氏奶发展问题提出了针对性的建议,最后围绕新消费下的特点,重构“人货场”三要素,以期激活消费者的购买力。 相似文献
108.
Sophie Miyumo Chrilukovian B. Wasike Evans D. Ilatsia Jörn Bennewitz Mizeck G. Chagunda 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2023,140(1):106-120
This study aimed at investigating the influence of genetic and non-genetic factors on immune traits to inform on possibilities of genetic improvement of disease resistance traits in local chicken of Kenya. Immune traits such as natural and specific antibodies are considered suitable indicators of an individual's health status and consequently, used as indicator traits of disease resistance. In this study, natural antibodies binding to Keyhole Limpet Hemocyanin (KLH-NAbs) was used to measure general disease resistance. Specific antibodies binding to Newcastle disease virus (NDV-IgG) post vaccination was used to measure specific disease resistance. Titers of KLH-NAbs isotypes (KLH-IgM, KLH-IgG and KLH-IgA) and NDV-IgG were measured in 1,540 chickens of different ages ranging from 12 to 56 weeks. A general linear model was fitted to determine the effect of sex, generation, population type, phylogenetic cluster, line, genotype and age on the antibody traits. A multivariate animal mixed model was fitted to estimate heritability and genetic correlations among the antibody traits. The model constituted of non-genetic factors found to have a significant influence on the antibody traits as fixed effects, and animal and residual effects as random variables. Overall mean (±SE) concentration levels for KLH-IgM, KLH-IgG, KLH-IgA and NDV-IgG were 10.33 ± 0.04, 9.08 ± 0.02, 6.00 ± 0.02 and 10.12 ± 0.03, respectively. Sex, generation and age (linear covariate) significantly (p < 0.05) influenced variation across all the antibody traits. Genotype effects (p < 0.05) were present in all antibody traits, apart from KLH-IgA. Interaction between generation and line was significant (p < 0.05) in KLH-IgM and NDV-IgG while nesting phylogenetic cluster within population significantly (p < 0.05) influenced all antibody traits, apart from KLH-IgA. Heritability estimates for KLH-IgM, KLH-IgG, KLH-IgA and NDV-IgG were 0.28 ± 0.08, 0.14 ± 0.06, 0.07 ± 0.04 and 0.31 ± 0.06, respectively. There were positive genetic correlations (0.40–0.61) among the KLH-NAbs while negative genetic correlations (−0.26 to −0.98) were observed between the KLH-NAbs and NDV-IgG. Results from this study indicate that non-genetic effects due to biological and environmental factors influence natural and specific antibodies and should be accounted for to reduce bias and improve accuracy when evaluating the traits. Subsequently, the moderate heritability estimates in KLH-IgM and NDV-IgG suggest selection possibilities for genetic improvement of general and specific immunity, respectively, and consequently disease resistance. However, the negative correlations between KLH-NAbs and NDV-IgG indicate the need to consider a suitable approach that can optimally combine both traits in a multiple trait selection strategies. 相似文献
109.
110.