单糖间的协同作用可提高仔猪生产性能

乳制品在幼龄动物日粮中的作用非常重要。乳糖 ( lactose)是仔猪的主要能量来源。最新研究结果表明 ,2～ 3周龄断奶仔猪不仅能利用乳糖 ,还能利用蔗糖 ( sucrose)来作为能量来源。蔗糖、果糖 ( fructose)、葡萄糖 ( glucose)和麦芽糖( maltose)等可有效替代仔猪乳糖需要量的 5 0 %。1　开食料中乳糖乳制品提供乳糖的同时还提供了高质量的乳蛋白以及具有生物学利用价值高的矿物质和维生素。乳糖是由葡萄糖和半乳糖 ( galactose)组成的二糖。在乳糖酶 ( lactase)的作用下 ,乳糖才能降解成它的单糖组分。初生仔猪体内的乳糖酶含量较高 ,可有效…     

乳糖酶研究进展

乳糖酶具有将乳糖水解为半乳糖和葡萄糖,以及半乳糖苷转移作用。乳糖酶主要应用于对乳糖不耐受症的治疗以及对乳制品的加工改良等领域。许多患有乳糖不耐受症群体的体内缺少乳糖酶,使得乳糖不耐受症的患者不能在小肠内将乳糖分解,     

不同乳糖酶水解率的对比分析

乳糖酶在特定条件下可将乳糖水解成葡萄糖和半乳糖，对人体健康有重要作用。本文简要介绍了乳糖酶的功能及应用，并通过UHT乳乳糖水解试验对比几种乳糖酶的水解率，从而确定水解率高的乳糖酶。     

帝斯曼乳糖酶产品为乳糖不耐受的中国消费者带来福音

乳制品是人体获取蛋白质及钙的良好来源，但由于我国乳糖不耐症人群所占比例较高，阻碍了乳制品的推广。世界健康组织数据表明，乳糖不耐症或乳糖酶缺乏的人群在中国占85%以上。乳糖酶可以使乳糖水解为葡萄糖和半乳糖，通过降低乳糖含量使乳糖不耐症人群能够少量或正常地摄入乳制品。     

乳糖酶的特性及其在乳品工业中的应用

乳和乳制品的营养价值早已得到世人的公认,然而由于部分人群体内缺乏乳糖酶导致的乳糖不耐受现象,影响了人们对于乳制品的正常摄入,这在很大程度上也就制约了乳制品在人们日常生活中的普及和人体对乳制品营养成分的消化吸收.随着现代生物技术的发展,人们可利用乳糖酶定向水解牛乳中大量的乳糖,使得从根本上解决乳糖不耐受这一难题成为可能.本文就乳糖酶的来源、     

哪些人不宜喝牛奶

1．乳糖酶缺乏的人不能喝牛奶。牛奶中乳糖含量高，不能直接被人体吸收，必须在消化道乳糖酶的作用下，分解为半乳糖和葡萄糖才能够被吸收。如果乳糖酶缺乏，食用牛奶后会引起腹痛、腹泻。     

贮存温度对液体乳糖酶活性的影响

乳糖酶,别名β-半乳糖苷酶,主要应用于乳品行业,其主要作用是使乳糖水解为葡萄糖和半乳糖。由于乳糖酶存在受热降解的特性,在对其进行贮存的过程中,乳糖酶的活性会随贮存温度的变化而变化。对不同温度条件下贮存的液体乳糖酶活性进行了对比检测与分析。     

低乳糖脱脂鲜牛奶的研究

以新鲜的脱脂牛乳为原料,应用乳糖酶对脱脂牛乳中的乳糖进行水解,经杀菌灭酶研制了营养丰富,且具有保健功效的低乳糖脱脂牛奶。乳糖酶在脱脂牛乳中最适水解条件为：水解温度35℃,水解时间2h,乳糖酶添加量1.2g/L,脱脂牛乳经乳糖酶水解,其乳糖水解率达到65%以上。     

乳糖不耐受和低乳糖奶

本文介绍了乳糖的生理功能,乳糖不耐受及其克服途径以及开发低乳糖奶的重要意义.指出利用乳糖酶解技术开发低乳糖奶和低乳糖乳制品,对提高牛奶和乳制品的营养价值,增加乳制品的销量将起到很大作用,其市场潜力巨大,经济、社会效益显著.     

乳糖吸收不良与乳品消费（一）——让每个人拥有牛奶梦想成真

乳糖过敏使亚太地区的许多人无法享受乳制品的营养价值。但是，乳糖酶使得全球乳品工业开发出为乳糖过敏消费者所接受的新型低乳糖产品成为可能。乳糖是哺乳动物乳中甜度较低的二糖，其溶解度低，不能被肠道直接吸收。但其水解成分葡萄糖和半乳糖的溶解性比乳糖高3～4倍，容易被肠道吸收。在人体内，只有这些单糖才被用作能量来源或合成材料。     

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.

     

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.