中链脂肪酸在动物生产中的应用效果及其影响因素研究进展

中链脂肪酸（MCFA）是一类具有特殊生理功能的能源物质，与长链脂肪酸（LCFA）相比，MCFA的碳链更短，到达肝脏的速度更快，MCFA可直接经门静脉运输至肝脏，且无需肉碱脂酰转移酶的转运即可直接进入肝细胞线粒体进行β氧化。因此，MCFA被动物吸收的更直接、更快速，供能也更直接。MCFA不但可为动物机体提供能量，还具有超出其能量价值之外的特殊生理功能，包括抑制细菌的生长和改善肠道微生态及结构，参与动物机体的免疫调节和激素调节等。MCFA的营养特点和生理功能为其在动物生产上的应用提供了依据，在动物生产应用方面，MCFA可提高动物生长性能，减少反刍动物瘤胃甲烷的排放，预防动物疾病，延长畜禽产品货架期，有效控制蚊蝇对家畜的侵扰，MCFA与一些其他饲料添加剂联合使用，不仅存在协同效应，还可克服其在实际生产应用中的缺点。近年来，使用安全、绿色的饲料添加剂替代动物饲料中抗生素的呼声越来越高，MCFA也逐渐受到大众的关注。然而，MCFA在研究和生产应用中存在效果差异，究其原因可能与MCFA的种类、添加水平、添加方式等因素有关。文章对MCFA的营养特点、生理功能、应用于动物生产的效果及其影响因素进行了综述，旨在为MCFA的深入开发与合理利用提供理论依据。     

中链脂肪酸的生化及代谢特征与其在畜禽生产中应用的研究进展

中链脂肪酸（medium chain fatty acids,MCFA）是指碳原子数为6～12的一类脂肪酸,所有天然存在的脂肪酸均由C2单元（乙酰辅酶a）组成,因此碳原子数为偶数（如己酸C6、辛酸C8、癸酸C10、月桂酸C12）。MCFA不仅可以作为能源物质,还具有抗菌、调节免疫、维护肠道健康、防治疾病以及提高动物生长性能等作用,因而也可作为替抗产品。文章对MCFA的生物学功能和作用机制进行了简述,概述其在畜禽生产方面的应用,旨为MCFA在养殖业中的进一步应用提供参考。     

中链脂肪酸在动物生产中的应用效果及其影响因素研究进展

中链脂肪酸(MCFA)是一类具有特殊生理功能的能源物质,与长链脂肪酸(LCFA)相比,MCFA的碳链更短,到达肝脏的速度更快,MCFA可直接经门静脉运输至肝脏,且无需肉碱脂酰转移酶的转运即可直接进入肝细胞线粒体进行β氧化。因此,MCFA被动物吸收的更直接、更快速,供能也更直接。MCFA不但可为动物机体提供能量,还具有超出其能量价值之外的特殊生理功能,包括抑制细菌的生长和改善肠道微生态及结构,参与动物机体的免疫调节和激素调节等。MCFA的营养特点和生理功能为其在动物生产上的应用提供了依据,在动物生产应用方面,MCFA可提高动物生长性能,减少反刍动物瘤胃甲烷的排放,预防动物疾病,延长畜禽产品货架期,有效控制蚊蝇对家畜的侵扰,MCFA与一些其他饲料添加剂联合使用,不仅存在协同效应,还可克服其在实际生产应用中的缺点。近年来,使用安全、绿色的饲料添加剂替代动物饲料中抗生素的呼声越来越高,MCFA也逐渐受到大众的关注。然而,MCFA在研究和生产应用中存在效果差异,究其原因可能与MCFA的种类、添加水平、添加方式等因素有关。文章对MCFA的营养特点、生理功能、应用于动物生产的效果及其影响因素进行了综述,旨在为MCFA的深入开发与合理利用提供理论依据。     

维持猪群肠道健康的自然方法

不同脂肪酸的抗菌活性在实践中是众所周知的。脂肪酸和其他物质的靶向组合可以广泛改善动物肠道健康,减少抗生素的使用。由于法律法规要求在畜牧业生产中要减少抗生素的使用,不同的脂肪酸在动物营养中发挥着越来越重要的作用。由于中链脂肪酸(MCFA)具有很强的抗菌活性和能量供应成分,因此在猪生产中,寻找抗生素的替代品激发了人们对MCFA的兴趣。其不但可促进肠道绒毛的生长,还可增加饲料的消化率,也可以改善断奶后仔猪的肠道发育。     

PIG PROGRESS维持猪群肠道健康的自然方法

不同脂肪酸的抗菌活性在实践中是众所周知的.脂肪酸和其他物质的靶向组合可以广泛改善动物肠道健康,减少抗生素的使用.由于法律法规要求在畜牧业生产中要减少抗生素的使用,不同的脂肪酸在动物营养中发挥着越来越重要的作用.由于中链脂肪酸(MCFA)具有很强的抗菌活性和能量供应成分,因此在猪生产中,寻找抗生素的替代品激发了人们对MC...     

中链脂肪酸调控猪禽生理代谢和健康的研究进展

中链脂肪酸(MCFA)是一类由6～12个碳原子构成的饱和脂肪酸,主要包括已酸、辛酸、癸酸和月桂酸.MCFA及其衍生物是良好的抑菌剂、防腐剂和饲料添加剂,在化工、化妆品、医药、畜牧等行业广泛应用.文章综述了MCFA的理化性质、消化代谢特征以及脂质代谢调节、杀菌、抗炎等生物学功能,为MCFA在猪、禽养殖中的应用提供参考.     

脂肪酸营养生理作用及其在动物生产中的应用

1脂肪酸的定义及分类 脂肪酸是由碳、氢和氧3种元素组成的一类化合物,是构成动物机体脂肪和类脂的基本物质,是细胞膜磷脂的重要成分,对调节细胞膜组成和蛋白质摄入具有重要意义.依据脂肪酸间碳氢链的长度及不饱和双键的数目和位置进行划分.脂肪酸按碳氢链是否饱和可分为3类,即:饱和脂肪酸(SFA),单不饱和脂肪酸(MUFA)和多不饱和脂肪酸(PUFA);按碳链的长短可将脂肪酸分为短链脂肪酸(SCFA)、中链脂肪酸(MCFA)及长链脂肪酸(LCFA).     

中链脂肪酸的生物学特点及对仔猪生产性能的影响

中链脂肪酸因其特殊的生理学作用,不仅能够为幼龄动物提供营养,而且对病原菌具有抑菌作用,能够提高幼龄动物的免疫力和抗应激能力。本文就中链脂肪酸的生物学特点以及对仔猪生产性能的影响进行了概述。     

中链脂肪酸甘油三酯在养猪业中的应用

正中链脂肪酸(MCFA)是指链长为6~12C的饱和脂肪酸,其具备特殊的生理活性功能,能够快速为幼小动物供应能量,抑制细菌调节肠道结构,不仅促进生长提高饲料转化率,还能提高母猪的繁殖性能等。本文简单介绍了中链脂肪酸酯化形成甘油三酯(MCT)后的理化性质、代谢特点、生产工艺等,同时综述了其在养猪业中的应用与进展。脂肪是猪体组织的主要成分,也是其饲粮的重要成分。近年来对脂肪的研究不断深入,同时也推动了更多     

脂肪酸的生理功能及在畜禽养殖中的应用

脂肪酸在动物机体的营养物质代谢以及生理机能发育中发挥着重要的作用,通常分为短链脂肪酸、中链脂肪酸以及长链脂肪酸等不同类型。脂肪酸是一种长度可变的碳氢链,一端是甲基,另一端是羧基。脂肪酸具有抗氧化、抗炎、抗菌、抗病毒等多种生理功能,在当前禁抗大背景下,脂肪酸以其良好的抗菌效果而逐渐被用作抗生素替代品。现阶段的脂肪酸研究中对于短链脂肪酸的研究较为广泛,但是对于中链脂肪酸和长链脂肪酸的研究较少,下文将对中链脂肪酸和长链脂肪酸的生理功能以及它们在畜禽生产中的应用进行介绍,旨在为脂肪酸的科学应用以及我国畜禽养殖产业的科学发展提供帮助。     

Heartworm in dogs in Canada in 1985

In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%).

Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1988

In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%).     

Heartworm in dogs in Canada in 1984

In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal.

Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection.

     

Heartworm in dogs in Canada in 1991

In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium.     

Heartworm in dogs in Canada in 1989

In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated.

Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively.

     

Heartworm in dogs in Canada in 1987

In late November 1987, 1246 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%).     

Heartworm in dogs in Canada in 1986

In late December 1986, 1224 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%).

Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1983

In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario.

Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously.