奶牛TMR中添加陈皮对乳风味的影响

试验选用4头中国荷斯坦泌乳奶牛采用4×4拉丁方试验设计研究了TMR中添加不同水平(0、300、600、900 g/d.头)的陈皮对奶牛乳风味的影响,并采用GC-MS分析了陈皮中的主要挥发性活性物质及添加陈皮后乳中风味物质种类及含量。结果表明:在奶牛TMR中添加陈皮对奶牛的采食量及乳成分无影响(P>0.05),在添加量为300、600 g时的产奶量显著高于对照(P<0.05),在添加量为600 g时,牛奶的色泽、异味感和甜味与对照相比均有显著改善(P<0.05);陈皮挥发油中的主要化合物是柠檬烯、γ-松油烯、β-月桂烯、α-蒎烯、β-蒎烯等;添加陈皮的牛奶中能检测出陈皮中所特有的一些芳香性化合物,如柠檬烯、γ-榄香烯、乙基亚麻酸、油酸、油醇等,且这些化合物在牛奶中的含量随着日粮中陈皮添加水平的增加而增加。结果提示,饲料中添加600 g(/d.头)陈皮能提高奶产量及改善奶风味。     

奶牛料矿物元素不可少

在为产奶牛设计日粮时．大多数奶农只考虑蛋白质、能量和脂肪的指标．而往往不注意微量元素的含量。奶牛每天从泌乳中失去大量的微量元素．如果不能从日粮中及时得到补充，奶牛很容易得病。虽说缺乏微量元素不会引起奶牛很快死亡．但是会在一定程度上造成奶牛生产性能降低，产奶量下降，从而影响奶农的经济效益。     

饲料药物添加剂的使用注意事项

(一)添加脂肪类1.脂肪酸钙:奶牛日粮中添加脂肪酸钙300克/天·头,能使奶牛产奶量提高,乳脂率提高13.16%;奶中悬脂、亚油酸、钙分别增加18.20%、25.55%、17.25%。2.脂肪:每头奶牛每天添加364克脂肪,能提高产奶量,乳脂率提高13%～18%。(二)添加维生素类⒈添加烟酸:添加烟酸能使奶     

保持奶牛优质高产 五类添加剂不可少

1脂肪类1.1脂肪酸钙每头奶牛日粮中添加脂肪酸钙300g,可使奶牛产奶量明显提高,乳脂率提高13.16%;奶中悬脂、亚油酸、钙分别增加18.20%、25.55%、17.25%。1.2脂肪每头奶牛每天添加364g脂肪,能提高产奶量,乳脂率提高13%￣18%。2维生素类2.1添加烟酸添加烟酸能使奶牛的产奶量提高2.3%￣11.7%,乳脂率提高2.0%￣13.7%。2.2胡萝卜素奶牛产奶前30d和产奶后92d,日粮中补加7g胡萝卜素制剂,每个泌乳期净增产牛奶200kg,而且奶中的维生素A含量提高21.5%。2.3维生素E乳牛日粮中添加维生素E,不但能增强乳牛机体免疫力,提高泌乳量,还可以防止奶中脂肪氧化…     

奶牛怎样补饲脂肪

奶牛日粮中脂肪的含量最多不能超过日粮干物质的7％。在正常情况下,奶牛基础日粮本身就含有3％左右的脂肪。因此,补充量一般为3％～4％,即1天1头奶牛应补充0．45～1-36kg脂肪。如果日粮中脂肪的添加量超过7％．就会降低瘤胃微生物的     

烟酸对饲喂棉籽奶牛的奶蛋白量效果

试验证明,给高产奶牛饲喂脂肪,增加日粮热量浓度,结果奶产量和乳脂率提高。棉籽配合于奶牛日粮,作为其脂肪来源之一,在一些产棉地区是常见的。但其中有一     

果味剂对奶风味及奶牛生产性能的影响

试验选择了24头泌乳前中期的同一胎次、健康无病、具有相近体重、产奶量与泌乳期的荷斯坦奶牛,将其分为4组,每组6头牛,在奶牛日粮中添加苹果味果味剂、香蕉味果味剂、混合香型果味剂,并设置对照组(不添加果味剂)进行奶牛饲养试验。对奶牛的生产性能以及奶样中风味物质进行评定。试验结果表明:①在奶牛生产性能方面,与对照组相比,3种果味剂都有减缓产奶量下降的趋势,其中香蕉味的作用效果最好(产奶量下降:香蕉味0.5%,苹果味11.9%,混合味8.86%,对照13.5%)。②对奶样进行感官评价,在单独的色泽、组织状态、奶香味、果香味、甜味、酸味、苦味、涩味、饲草味和牛体味中,4种样品基本没有差异,4个样品的综合风味存在显著差异(P<0.05),在风味的总得分上,混合风味>苹果风味>香蕉风味=对照组。     

单个脂肪酸可获得更精准地饲喂

正当提到脂肪补充时,新的研究产生了一个全新的领域。所有脂肪都会给日粮提供能量。但是,单个脂肪酸也会影响奶牛的消化率、代谢、能量分配和产奶量反应。补充时间、泌乳阶段,甚至日粮中饲草的数量,所有这些都会影响奶牛如何反应。美国密歇根州立大学奶牛营养副教授Adam Lock说,在奶牛营养中,这是一个令人兴奋的时刻。研究表明,并不是所有的脂肪都是一样的。就像在日粮配合中氨基酸替代     

过渡期奶牛的饲喂要点

干奶牛 干奶末期奶牛(产前21天)饲喂方案的关键点如下: 由于应激和激素变化,奶牛在分娩前会降低干物质摄入量(DMI)。重要的是应重视DMI的这一变化,应提高日粮的能量密度。将干奶末期奶牛的日粮进行调整,使奶牛的DMI达到10-11kg。     

保护性脂肪对奶牛乳成分的影响

夏季的高温可以使奶牛的采食量下降，身体消瘦，奶牛体内营养平衡处于入不敷出的状态，造成奶牛体内能量的负平衡。为了减少或避免奶牛泌乳期能量代谢的负平衡，既提高日粮能量浓度，又不致于降低乳脂率，可以在不改变日粮粗、精料比例的前提下，在日粮中可添加适量的脂肪。本研究为进一步探明保护性脂肪对奶牛乳成分的影响，进行了具体的实验研究。     

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.     

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.     

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     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

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

Tropical Animal Health and Production -