酸化乳体系的稳定性研究进展

酸化乳体系中常见乳清析出问题,导致沉淀分层现象.向酸化乳中加入稳定剂可防止这一现象的发生.本文阐述了果胶等亲水胶体在酸性乳体系中稳定作用的机理,为研究其他稳定剂在食品中的应用提供了思路,扩大了稳定剂的研究范围.     

牛奶体外抗菌活性体系--乳过氧化物酶体系的应用

本文主要综述了牛奶体外抗菌活性体系——乳过氧化物酶体系的组成、抑菌机制及其在牛奶保鲜中的应用。     

乳过氧化物酶体系的性质及利用

本文属科普性综述。旨在介绍一种抗菌体系－－乳过氧化物酶体系的组成，抑菌机理，包括其作用方式和影响因素，以及在牛乳保藏过程中的应用     

县级生鲜乳质量检测体系建设与应用

千阳县围绕标准化奶牛养殖示范县建设工作,在陕西省率先建成县级生鲜乳质量检测中心,并以县级生鲜乳质量检测中心为核心,各小区奶站检测实验室为基础,形成了县、乡两级生鲜乳质量检测体系,为开展生鲜乳质量检测工作奠定了基础。本文就千阳县生鲜乳质量检测体系建设及生鲜乳质量检测技术的应用情况做以简要分析。     

乳过氧化氢酶体系在牛乳保鲜中的应用

由于三聚氰胺事件影响,乳品安全已日益得到_广大消费者的重视,生物酶制剂在牛乳保鲜中取得了良好的效果.本文从组成、抗酋机理、保鲜效果等方面探讨了鲜牛奶中固有的一种天然抗菌活性体系-乳过氧化物酶体系(LPS)在牛乳保鲜中的应用,并结合当前研究进展论述了它在牛乳保鲜中的效果,为牛乳保鲜提供了新的方法.     

乳过氧化氢酶体系在牛乳保鲜中的应用

由于三聚氰胺事件影响,乳品安全已日益得到广大消费者的重视,生物酶制剂在牛乳保鲜中取得了良好的效果。本文从组成、抗菌机理、保鲜效果等方面探讨了鲜牛奶中固有的一种天然抗菌活性体系-乳过氧化物酶体系(LPS)在牛乳保鲜中的应用,并结合当前研究进展论述了它在牛乳保鲜中的效果,为牛乳保鲜提供了新的方法。     

利用乳过氧化氢酶体系保鲜生牛乳的试验研究

正牛奶中的天然抗菌活性体系——乳过氧化物酶体系的抗菌活性主要是以乳过氧化物酶(LP)作为催化剂,通过H_2O_2氧化SCN~-生成具有抗菌活性的OSCN~-,以激活本身的过氧化物酶形成天然的抗菌活性体系,从而达到抗菌目的。虽然牛乳中也含有少-     

千阳县生鲜乳质量检测体系建设的创新点

近年来,牛奶的质量安全已成为社会关注的焦点和热点问题,建立生鲜乳质量检测体系,对加强生鲜乳质量管理,推动奶源基地建设和奶牛科学饲养管理具有十分重要的作用和意义. 目前,陕西省千阳县建成县级生鲜乳质量检测中心1个、生鲜乳收购站化验室37个,生鲜乳质量检测覆盖全县所有产奶牛,形成了以县级生鲜乳质量检测中心为基础,各生鲜乳收购站化验室为基础检测点的两级生鲜乳质量检测体系,通过奶站自检—检测中心抽检—企业复检的工作程序,对生鲜乳中的理化、生物、卫生安全等指标进行检测,为奶牛科学饲养管理提供了依据,保障了生鲜乳质量安全.从201 1年2月至2012年12月,县生鲜乳质量检测中心在全县7个牛场、37个奶站累计检测奶样27080份,奶牛单产提高0.63吨,增加经济效益4013.3万元,经济、社会效益显著.     

国际标准化组织(ISO)乳与乳制品标准体系

我国和其他乳类生产、消费大国在乳与乳制品标准的制定和实施方面存在着很大的差距.本文通过收集整理国际标准化组织(international standardization organization,ISO)乳与乳制品相关标准,对ISO乳与乳制品标准体系的构成、现状及特点进行了介绍和剖析,并与我国乳与乳制品标准体系现状进行了对比分析.     

高黏度酸化乳体系的稳定性

酸化乳口感细腻、风味独特,深受消费者的喜爱。但在加工贮藏过程中容易出现乳清析出、蛋白质沉淀、絮凝等体系不稳定问题。果胶和其他稳定剂协同作用可以使酸化乳体系稳定且口感较好。通过测定产品黏度、持水力、乳清析出率及感官特性,研究不同食品胶对酸化乳产品的影响。结果表明：果胶、海藻酸丙二醇酯（propylene glycol alginate,PGA）和羧甲基纤维素钠（carboxymethylcellulose sodium,CMC-Na）3 种胶体复配使用时,酸化乳体系黏度适中、体系稳定且口感较好。筛选出黏度合     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein