牛初乳蛋白质的营养价值和开发利用

蛋白质是牛初乳中最重要的营养物质之一,具有独特的化学成分和生理作用。本文介绍了牛初乳蛋白质的含量及变化规律,牛初乳蛋白质中乳清蛋白和酪蛋白的比率,牛初乳蛋白质的氨基酸组成以及牛初乳中的免疫因子和生长因子等活性蛋白成分;分析评价了牛初乳蛋白质的营养价值;并对扩大牛初乳资源的开发利用提出了建议。     

牛初乳中生长因子及抗菌因子的生物活性及其功能研究进展

主要介绍了牛初乳中富含生理活性功能的活性成分——生长因子(胰岛素样生长因子、转化生长因子、表皮生长因子、成纤维细胞生长因子)及抗菌因子(乳铁蛋白、溶菌酶、乳过氧化物酶、免疫球蛋白)生理活性和功能的最新研究进展,同时,对牛初乳中各因子作为保健产品和医疗药品基料的趋势作出展望。     

黑龙江省奶业关键技术研究取得突破

本刊辑：日前，黑龙江省“十一五”重大科技攻关项目“现代奶业关键技术研究与产业化示范”及其6个子项，通过了黑龙江省科技厅组织的专家鉴定。该项目整体研究水平国内领先，在离子交换层析技术提取牛初乳免疫活性物质方面达到国际先进水平。     

牛初乳粉对凝固型酸奶质量的影响

本文主要研究了嗜热链球菌和保加利亚乳杆菌在发酵过程中对牛初乳IgG活性的影响,结果表明添加冻干牛初乳粉的酸奶在42～43℃发酵过程中,通过琼脂单向免疫扩散法(SRID)测得IgG活性约损失了20%,而在冷藏14天后,IgG活性约损失了28%;添加牛初乳粉可促进乳酸菌产酸。通过感官评定得出开发含有牛初乳的凝固型酸奶是可行。     

中国乳制品工业行业规范 RHB 602-2005牛初乳粉

前言牛初乳是母牛分娩后最初几天所分泌的乳汁。20世纪50年代以来,由于生理学、生物化学、医学及分子生物学的发展,发现牛初乳中不仅含有丰富的营养物质,而且含有大量的免疫因子和生长因子,如免疫球蛋白、乳铁蛋白、溶菌酶、类胰岛素生长因子、表皮生长因子等,具有免疫调节、改善胃肠道、促进生长发育、改善衰老症状、抑制多种病原微生物等一系列生理活性功能,因而被誉为“21世纪的保健食品”。最近几年,牛初乳已成为食品及功能性乳制品开发的热点,牛初乳生产加工企业、牛初乳制品种类和品种越来越多。为更好地规范牛初乳产品市场,保护消费…     

中国乳制品工业行业规范 RHB 601-2005生鲜牛初乳

前言牛初乳是母牛分娩后最初几天所分泌的乳汁。20世纪50年代以来,由于生理学、生物化学、医学及分子生物学的发展,发现牛初乳中不仅含有丰富的营养物质,而且含有大量的免疫因子和生长因子,如免疫球蛋白、乳铁蛋白、溶菌酶、类胰岛素生长因子、表皮生长因子等,具有免疫调节、改善胃肠道、促进生长发育、改善衰老症状、抑制多种病原微生物等一系列生理活性功能,因而被誉为“21世纪的保健食品”。最近几年,牛初乳已成为食品及功能性乳制品开发的热点,牛初乳生产加工企业、牛初乳制品种类和品种越来越多。为更好地规范牛初乳产品市场,保护消费…     

恒天然集团利用专利技术将牛初乳引入主流饮品市场

本刊讯:牛初乳是大自然提供给新生命的初始食物,富含多种活性成分以及满足市场需求的新兴的功能性成分。目前市场上主要的牛初乳类产品形式是片剂、胶囊和粉。生产商至今仍然无法生产长保质期的即饮牛初乳饮品。传统的热处理工     

生鲜牛初乳

牛初乳是母牛分娩后最初几天所分泌的乳汁。20世纪50年代以来，由于生理学、生物化学、医学及分子生物学的发展，发现牛初乳中不仅含有丰富的营养物质，而且含有大量的免疫因子和生长因子，如免疫球蛋白、乳铁蛋白、溶菌酶、类胰岛素生长因子、表皮生长因子等，具有免疫调节、改善胃肠道、促进生长发育、改善衰老症状、抑制多种病原微生物等一系列生理活性功能，因而被誉为“21世纪的保健食品”。最近几年，牛初乳已成为食品及功能性乳制品开发的热点，牛初乳生产加工企业、牛初乳制品种类和品种越来越多。为更好地规范牛初乳产品市场，保护消费者合法权益，促使生产企业的合法、公平竞争，引导牛初乳产业健康、持续发展，特制定本行业规范。     

牛初乳粉

牛初乳是母牛分娩后最初几天所分泌的乳汁。20世纪50年代以来，由于生理学、生物化学、医学及分子生物学的发展，发现牛初乳中不仅含有丰富的营养物质，而且含有大量的免疫因子和生长因子，如免疫球蛋白、乳铁蛋白、溶菌酶、类胰岛素生长因子、表皮生长因子等，具有免疫调节、改善胃肠道、促进生长发育、改善衰老症状、抑制多种病原微生物等一系列生理活性功能，因而被誉为“21世纪的保健食品”。最近几年，牛初乳已成为食品及功能性乳制品开发的热点，牛初乳生产加工企业、牛初乳制品种类和品种越来越多。为更好地规范牛初乳产品市场，保护消费者合法权益，促使生产企业合法、公平竞争，引导牛初乳产业健康、持续发展，特制定本行业规范。     

活性牛初乳钙片的研制与生产

本文对活性牛初乳钙片的营养功能、参考配方、设备和生产工艺等进行了研究,并针对经常出现的质量问题提出了相应的解决办法。     

Cloning and expression of the cDNA for bovine granulocyte-macrophage colony-stimulating factor

A sequence encoding bovine granulocyte-macrophage colony-stimulating factor (GM-CSF) has been identified from a concanavalin A-stimulated bovine lymphocyte cDNA library. This sequence was isolated by hybridization with synthetic oligonucleotide probes based upon the human GM-CSF sequence. This bovine cDNA was engineered for expression and secretion of activity into the periplasmic space of E. coli. Periplasmic extracts contain a 14,500-dalton protein and stimulate colony formation of bovine bone marrow progenitor cells. The predicted protein is 70% homologous with human GM-CSF and 55% homologous with murine GM-CSF. Numerous structural features are conserved among these three proteins, such as location of cysteine residues, glycosylation sites, and overall change. The biological activity of bovine GM-CSF is species specific, since recombinant preparations do not cause proliferation of human or murine bone marrow cells. Similarly, murine GM-CSF does not exhibit activity on cells of bovine or human origin. However, human GM-CSF does stimulate colony formation of bovine bone marrow cells, although the specific activity appears reduced when compared to assays on human cells.     

Isolation of bovine complement factor H

A bovine serum protein, initially recognized by its inhibitory effect on the hemolytic activity of the bovine alternative pathway was isolated from fresh bovine serum by polyethylene glycol precipitation and chromatography on DEAE-Sephacel, CM-Sephadex A-50 and Sephadex G-200. The protein, a single chain polypeptide with an apparent molecular weight of 158,000, was identified as factor H, a regulatory protein of the alternative complement pathway. Functional characterization of this protein as factor H was based on the following properties: binding to C3b, inhibition of factor B binding to C3b, cofactor activity in the cleavage of C3b by factor I, inhibition of fluid phase alternative pathway C3 convertase (C3b.Bb) formation and activity, and species-specific inhibition of the alternative pathway mediated hemolysis of heterologous erythrocytes. A monospecific rabbit antiserum against bovine factor H failed to react with human serum factor H.     

牛肺泡表面活性蛋白A的分离纯化及抗菌活性分析

旨在分离纯化牛天然肺泡表面活性蛋白A(SP-A)和分析其抗菌活性,首先通过共价交联法制备出可特异吸附SP-A的麦芽糖-Sepharose(MS)胶粒,然后用MS胶粒从牛肺泡洗出液中吸附牛SP-A,从而得到牛SP-A.SDS-PAGE和Western blot检测表明,牛SP-A单体的相对分子质量为30 ku,二聚体为6...     

Production and purification of bovine monocyte-derived interleukin 1

Few studies have addressed the biological and molecular nature of bovine interleukin 1 (IL-1). In an effort to increase our understanding of the role of bovine IL-1 in bovine immunology, we investigated various parameters of its production by LPS-stimulated monocytes in vitro. Bovine monocytes isolated by our methods constitutively released IL-1 activity, as measured by the murine thymocyte IL-1 assay. Monocyte release of IL-1 activity was further augmented when the cells were incubated with 0.005-10 micrograms per ml of Escherichia coli lipopolysaccharide (LPS). The presence of 1, 5, or 10 percent heat-inactivated fetal bovine serum (FBS) enhanced LPS-stimulated bovine monocyte release of IL-1 activity as compared with monocytes cultured under serum-free conditions. We used a combination of size-exclusion and reverse-phase high-performance liquid chromatography (HPLC) to purify bovine IL-1 from serum-free monocyte culture supernatants. Size-exclusion HPLC resulted in a single peak of biological activity with an approximate molecular weight of 18,000 daltons. Further purification by reverse-phase HPLC demonstrated at least three major molecular species with IL-1 activity. Besides providing information about production of IL-1 by bovine monocytes in vitro, this study also describes a protocol to purify bovine IL-1 for future studies addressing its biological functions.     

Susceptibility of bovine macrophage and tracheal-ring cultures to bovine viruses.

Cultures of macrophages initiated from peripheral blood monocytes and organ cultures of tracheal rings were tested for their susceptibility to bovine viruses. With several notable exceptions, viruses cytopathogenic for bovine embryonic lung cultures were cytopathogenic for macrophages. Although cowpox virus replicated in macrophages, pseudocowpox did not, and although pseudorabies virus replicated within macrophages, infectious bovine rhinotracheitis and DN-599 herpesviruses did not. Bluetongue virus established an interesting relationship with macrophages. Whereas bluetongue virus was initially cytopathogenic for macrophages, it lost its cytopathogenicity on repeated passage, although it was capable of continued replication in macrophages. When subsequently passaged onto bovine embryonic lung cultures, it regained its cytopathogenicity. Parainfluenza-3, bovine viral diarrhea, and infectious bovine rhinotracheitis viruses readily destroyed ciliary activity in tracheal-ring cultures, as contrasted with the inability of bovine respiratory syncytial virus to destroy ciliary activity, even though bovine respiratory syncytial virus was able to replicate within ciliated epithelial cells of tracheal rings.     

Further biological, serological and biochemical characterization of North American, European and Southeast Asian strains of bovine herpesvirus 1 compared with other alphaherpesvirinae members

Hemagglutination activity, structural protein profiles and neutralization assays were used in a comparative study of bovine herpesvirus 1 strains from the U.S.A., Canada, Great Britain, Denmark and Malaysia with equine, feline and human herpesviruses in order to further characterize the bovine herpesvirus 1 hemagglutinin. Bovine herpesvirus 1 strains of different geographical origins all showed hemagglutinating activity for mouse erythrocytes; furthermore, feline herpesvirus 1 was also shown to hemagglutinate mouse erythrocytes. Analyses of partly purified viruses showed that a distinctive and specific polypeptides profile is associated with each species of herpesviruses used in our study; strains of bovine herpesvirus 1 from North America, Europe and Southeast Asia however, presented a remarkable similarity as to their electrophoretic protein patterns. A protein similar to the 97-kDa bovine viral hemagglutinin was not identified with the hemagglutinating feline herpesvirus. An important neutralization epitope on the bovine viral hemagglutinin was also not found on feline, equine and human herpesviruses but was identified on all bovine strains tested from North America, Europe and Southeast Asia stressing the importance of the bovine hemagglutinin for eventual prophylactic purposes.     

A canine pemphigus foliaceus case showing parallel relationship of disease activity and titer of serum anti-keratinocyte cell surface antibodies

A seven-year-old, spayed female mongrel dog was diagnosed as pemphigus foliaceus (PF) by clinical, histopathological and immunopathological observations. Serum antibodies against the cell surface of keratinocytes in the dog were detected by indirect immunofluorescence (IIF) using cryosectioned bovine esophagus as well as living cultured-canine keratinocytes as the substrates. When we compared the titers of IIF on bovine esophagus with its disease activity, the IIF titers reflected the disease activity throughout the time course. Our findings will suggest that sequential titration of serum antibodies by IIF will be useful for monitoring the serological disease activity in canine PF.     

A simple method for the in vitro determination of phagocytic activity of bovine polymorphonuclear leukocytes

A simple method for the in vitro determination of the phagocytic activity of bovine polymorphonuclear leukocytes (PMNL) is described. An enriched PMNL population was obtained from peripheral blood of healthy cattle and mixed with opsonized Candida utilis or with opsonized bovine red blood cells on BSA treated coverglass slides. The phagocytosis and killing of C. utilis was determined simultaneously on the coverglass slides stained with acridine orange. Phagocytosis of bovine erythrocytes was determined by microscopic examination of the Wright-Giemsa stained slides. This method is appropriate under limited laboratory conditions because it does not require highly sophisticated equipment and materials, it is easy and rapid to perform, reproducible and inexpensive. Therefore, it could be used as a first evaluation of the phagocytic activity of bovine PMNL.     

Isolation and identification of a bovine adenovirus type 3 with an adenovirus-associated virus.

A bovine adenovirus with agglutinating activity was isolated from feedlot calves and classified as serotype 3. The agglutinating activity was shown to be the property of an adenovirus-associated virus (AAV). The AAV was isolated from the bovine adenovirus by isopycnic centrifugation in CsCl; the AAV had a density of 1.4 g/cm2. This AAV is serologically related to bovine AAV-TR-15, but is distinct from bovine parvovirus-1 and primate AAV types 1 to 4, using counterimmunoelectrophoresis and hemagglutination-inhibition.     

Growth and metabolism of murine and bovine embryos in bovine uterine flushing-supplemented culture media.

The aim of this study was to compare the development and metabolic activity of cultured murine and bovine embryos in 2 standard media (HAM F-10 and RPMI) in the presence or absence of bovine uterine flushings. Murine morulae (n = 653) and day 7 bovine embryos (n = 273) were cultured for 18 h or 36 h in either HAM F-10 or RPMI in the presence or absence of bovine uterine flushings. After culture, the development, quality, and metabolic activity (glucose utilization or methionine uptake and incorporation) of embryos was assessed. It was found that HAM F-10 (without uterine flushings) was a more suitable medium than RPMI for optimal development and metabolism of murine and bovine embryos. Poor quality and development, as well as decreased metabolism, were evident after culture of murine embryos in RPMI; in contrast, this medium had no adverse effects on bovine embryos in culture. Supplementation of HAM F-10 with bovine uterine flushings improved the growth of murine embryos and the protein synthesis (as measured by an increased methionine incorporation) for both murine and bovine embryos. However, supplementation with bovine uterine flushings could not overcome deficiencies of an inappropriate medium (RPMI) for murine embryos. Supplementation of a well-defined culture medium with uterine flushings increased metabolism of embryos in culture, and thus might help to increase pregnancy rates after transfer of such embryos to recipient cows.