甜菜粕颗粒对泌乳奶牛泌乳性能、血液生化指标的影响

本试验旨在研究甜菜粕颗粒对泌乳奶牛生产性能、血液生化指标的影响。采用完全随机试验设计,选择体重、泌乳天数(135.96±25.98)d、胎次(1~2次)、产乳量(29.78±5.42)kg和生理状态相近的48头中国荷斯坦奶牛,随机分为4组,每组12头。对照组饲喂基础日粮,试验组分别以3.5%、5.5%、7.5%甜菜粕颗粒(干物质基础)替换基础日粮中部分玉米和燕麦草等。试验预试期1周,正试期6周。结果表明:对照组的干物质采食量、产奶量以及乳成分与试验组无显著性差异;与对照组相比,3.5%、5.5%、7.5%甜菜粕组血清中总蛋白含量分别提高了13.75%、13.34%、8.17%(P<0.05);3.5%和5.5%试验组的球蛋白含量分别提高了18.02%、18.35%(P<0.05);5.5%试验组葡萄糖含量降低了17.76%(P<0.05);7.5%试验组每天可盈利1.28元/头。在本试验条件下,添加7.5%甜菜粕颗粒不会对机体的糖分吸收以及代谢造成影响且经济效益最佳。     

红花粕和水飞蓟粕对生长獭兔的营养价值评定

本试验旨在通过饲养试验和消化试验来评定红花粕和水飞蓟粕在生长獭兔上的营养价值。选取18只60日龄左右、平均体重(1.73±0.21)kg、健康状况良好的白色獭兔,随机分为3个组,每组6个重复,每个重复1只兔。各组分别饲喂基础饲粮、红花粕饲粮(85%基础饲粮+15%红花粕)和水飞蓟粕饲粮(85%基础饲粮+15%水飞蓟粕)。预试期和正试期各5 d。采用化学分析法测定红花粕和水飞蓟粕的总能(GE)及各营养物质含量,采用全收粪法测定生长獭兔对各营养物质的表观消化率。结果表明:红花粕和水飞蓟粕中的GE、干物质(DM)、粗蛋白质(CP)、粗纤维(CF)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)、酸性洗涤木质素(ADL)、粗脂肪(EE)、粗灰分(Ash)、钙(Ca)、磷(P)以及无氮浸出物(NFE)的含量分别为:18.81 MJ/kg、93.76%、23.94%、14.95%、19.92%、11.99%、2.19%、1.64%、4.93%、0.37%、0.57%、49.32%与17.12 MJ/kg、91.94%、23.62%、16.21%、38.57%、22.73%、4.04%、2.07%、5.31%、0.29%、0.68%、42.09%。生长獭兔对红花粕和水飞蓟粕中GE、DM、CP、CF、NDF、ADF、EE、Ash、Ca、P和NFE的表观消化率分别为62.60%、61.72%、62.39%、15.68%、26.30%、14.75%、80.69%、38.35%、59.35%、31.98%、79.61%与63.13%、61.94%、68.01%、15.74%、27.64%、14.98%、79.90%、38.20%、60.44%、32.99%、79.81%。由此可见,生长獭兔对红花粕和水飞蓟粕中的不同营养成分的表观消化率存在一定差异,结合2种原料各营养物质含量总体分析,2种原料均可作为獭兔的蛋白质饲料资源应用,并且对生长獭兔的营养价值相近。     

不同方法处理的芝麻粕饲喂生长猪营养价值评定

随着人们的生活水平发生显著变化,对畜产品的消费量和品质要求相应提高,这对养殖业来说是个巨大的机遇.对饲料原料品质提出更多的要求.高品质饲料是生产优质畜产品的根本和基础,因此必须保证优质饲料的质与量.研究新型高品质的饲料资源,支持和发展畜牧业,是畜牧工作者面临的一个重要课题.微生物发酵法可以提高一些品质较差、营养不是十分平衡的原料的营养价值,而且有效降低抗营养因子含量,并产生一些对动物机体有益的活性肽类物质.发酵饲料是一种优质、绿色的饲料资源.但作为饲料资源不仅要要有充足的来源而且要有较高的营养价值.     

椰子粕等量替代玉米对泌乳牛和干奶牛的影响

[目的]为了掌握用椰子粕替代等量玉米对泌乳牛和干奶牛的影响。[方法]挑选健康的泌乳牛20头和干奶牛12头,遵循品种相同,年龄、胎次、产犊日、产奶量和体重相近的原则,将它们两两配对,随机分成试验组和对照组,两组的日粮结构和饲养管理制度基本一致,不同的是,试验组牛所用的试验精料改为在原相应精料基础上添加15%的椰子粕,替代等量的玉米,试验期间,定期记录试验牛的日产奶量,观察膘情和其他相关体征,看两组有何差异。[结果]结果显示:试验期间试验组牛的日平均产奶量为16.00kg,对照组为15.99kg,两组差异不显著(P0.05);试验组牛的平均体重为475.19kg,对照组为475.75kg,两组差异也不显著(P0.05),但是,用试验组精料每吨可节约成本168元。[结论]因此,在奶牛精料中添加15%的椰子粕替代等量玉米是可行的,奶牛场通过使用这样的日粮可以获得显著的经济效益。     

饲料营养价值评定对奶牛单产水平的提高作用及应用策略

随着畜牧业的发展和需求的增加,提高奶牛单产水平成为农牧业发展的重要目标之一。奶牛单产水平是指奶牛每批次产奶的量,通常以公斤为单位。单产水平是衡量奶牛生产效益的重要指标,饲料营养价值的高低直接影响奶牛的产奶量和奶质。高营养价值的饲料能提供充足的能量、蛋白质、矿物质和维生素等营养物质,满足奶牛生长发育和产奶的需要。通过饲料营养价值评定,可以了解饲料中各种营养成分的含量,为奶牛提供合适的饲料配方,以提高饲料的利用率和奶牛的单产水平。研究通过综合分析饲料营养价值评定对奶牛单产水平的影响,探讨应用饲料营养价值评定方案的策略来提高奶牛单产水平。期望利用饲料营养价值评定指导实施科学饲喂,提高奶牛的饲料利用率,增强奶牛的免疫力和健康状况,从而达到提高奶牛单产水平的目标。     

菊芋茎秆对荷斯坦奶牛泌乳性能及抗氧化能力的影响

为了研究菊芋茎秆对荷斯坦奶牛泌乳性能和抗氧化能力的影响,试验选择泌乳期30周的经产荷斯坦奶牛90头,TMR日粮饲喂量3周后,日粮添加10%菊芋青贮茎秆,饲喂3周。菊芋饲喂第1 d和21 d,颈静脉采血测定血液指标,7、14 d与21 d采集奶样,测定乳成分和乳抗氧化指标。研究结果表明:奶牛日粮添加10%菊芋青贮茎秆,不改变血液白细胞、红细胞和血小板总数,红细胞压积、平均体积、平均血红蛋白量和血红蛋白浓度,以及淋巴细胞比率(P>0.05);不影响乳汁酸度、乳蛋白浓度、非脂固形物含量和冰点值。可以提高血清中谷胱甘肽过氧化物酶(GSH-Px)活性(P<0.05),随着饲喂时间延长,乳汁中超氧化物歧化酶(SOD)活性(P<0.01)线性增加。奶牛饲喂10%菊芋青贮茎秆3周,可使乳脂率提高7.7%(P<0.05),血清GSH-Px活性提高10.4%(P<0.05),乳汁中GSH-Px和SOD活性分别提高18.7%和28.8%。因此,产奶牛饲喂菊芋可以改善奶牛血清和乳汁的抗氧化能力,提高乳脂率。菊芋可以作为提高乳汁品质和机体健康的饲料原料。     

在奶牛日粮中用菜粕代替酒糟蛋白质对其生产性能的影响

本试验旨在研究用菜粕(CM)代替奶牛日粮中的酒糟蛋白质对其生产性能的影响,8头泌乳荷斯坦奶牛(4头初产和4头经产的奶牛)被用于该试验,试验时间为4周。试验数据从第3周和第4周开始收集。分别用菜粕(CM)代替酒糟蛋白质中的100%、66%、33%和0的蛋白质。所有的奶牛日粮(平均含有15.1%的粗蛋白质和4.5%的乙醚提取物)中包含55%的粗饲料和45%的精料,其中粗饲料中含有50%的玉米青贮和苜蓿干草。试验数据显示,各处理组奶牛的干物质采食量(25.4kg/d)基本相似,产奶量也极其相似(各处理组奶牛的牛奶产量分别是35.2、35.8、34.5和34.3kg/d);各处理组中牛奶的蛋白质含量(3.04%)、脂肪含量(3.92%)和饲料转化率也基本相似。总体来看,用菜粕来代替奶牛日粮中的酒糟蛋白质是完全可行的。     

珍珠粟对泌乳及生长山羊的营养价值

前言 1994年,美国的玉米产量达到16114.6万吨,其中80％用作为家畜饲料或用于工业中(USDA,1994)。在美国的东南部,降雨不均衡,土壤呈酸性,加之害虫侵袭,这些对玉米生产都有不利的影响。Hill和Utiley(1989)研究了美国东南部高粱(sorghum)、珍珠粟(pearl millet)和黑小麦(triticale)的生产情况。在土壤贫瘠、气温偏高、降雨有限以及生长季节较短的条件下,珍珠粟的产量要高于其他谷物(Freeman Bocan,1973)。珍珠粟的粗蛋白含量高于玉米,其氨基酸构成也比玉米合理     

木薯对鸡的营养价值评定

为配合我省木薯的综合开发利用,我们用改进的TME法,对我省的木薯粉、木薯叶、木薯渣进行了鸡代谢能测定.材料与方法常规营养成份按照国标方法测定.代谢试验按改进的TME法进行.具体做法是选用单冠白来航成年健康公鸡6只,单只饲养在特制的笼里,试验前10天在其肛门外缝上     

Nutritional evaluation of transgenic cottonseed in the ration of lactating dairy cows

The effects of feeding transgenic (Bt) whole cottonseed (WCS) were studied in lactating cows. Twenty multiparous crossbred cows (Karan Swiss × Karan Fries) in early lactation were given a concentrate mixture containing 40% crushed delinted non-transgenic (non-Bt) WCS, 2 kg wheat straw and green fodder ad lib for a 15-day adaptation period. Thereafter, the cows were divided in two similar groups of 10 each on the basis of milk yield, body weight (BW) and date of calving. The non-Bt control group continued on same ration, while for the Bt group the non-Bt WCS was replaced by transgenic WCS, in a feeding trial of four weeks. The diets provided a minimum of 2 kg cottonseed/cow/d. Mean DMI/100 kg BW and milk yield of non-Bt and Bt groups was 3.48 and 3.45 kg and 11.4 and 12.0 kg/d, respectively. Intake of nutrients, digestibility, milk production and body condition score (BCS) did not differ between the groups (P > 0.05), but BW gain was higher (P < 0.05) in the Bt group than the non-Bt group, probably as a result of hoof problem in two cows of non-Bt group, which when compared excluding two animals from each group did not differ significantly (P > 0.05). Transgenic protein (Cry1C) was not detected in the weekly milk samples or in blood plasma at the end of the experiment, showing that delinted WCS containing Cry1C protein can safely be fed to lactating cows.     

不同豆粕添加量的日粮对奶牛产奶性能的影响

将40头荷斯坦产奶牛随机分为4个试验组,每组10头。4种试验日粮均配制成蛋白质(CP)含量15.2%、产奶净能(NEL)6.90~7.06 MJ/kg。日粮通过调节豆粕和棉籽粕的用量改变日粮赖氨酸(Lys)含量,这样试验1组日粮赖氨酸含量为0.65%、试验2组0.62%、试验3组0.59%和试验4组0.56%。所有试验奶牛先饲喂10 d试验日粮作为预试期,然后开始70 d正试期。试验1组产奶量最高,平均为(27.13±1.53)kg/d;试验4组产奶量最低,平均为(24.40±1.56)kg/d;试验2组和3组依次为(26.18±1.37)和(25.27±1.58)kg/d;其中试验1组产奶量明显高于试验3组(P<0.01)和试验4组(P<0.01),试验2组明显高于试验4组(P<0.05)。因此,在日粮蛋白质含量保持相同和产奶净能相近的条件下,提高日粮赖氨酸含量则提高了奶牛产奶量,降低日粮赖氨酸含量则降低了奶牛产奶量;大量使用棉籽粕替代豆粕降低日粮赖氨酸含量,导致产奶量降低;尽管日粮赖氨酸含量容易提高奶牛日粮成本,由于提高产奶量,增加了产奶纯收入。使用日粮赖氨酸含量这一指标有利于评价奶牛产奶量、乳成分和经济效益。     

Nutritional myodegeneration in dairy cows

A syndrome is described in which parturient dairy cows showed clinical signs consistent with milk fever but failed to respond to conventional therapy. The affected cows were reluctant to walk, moved stiffy and in severe cases became recumbent. The condition was apparently precipitated by low vitaimin E and selenium intake, stress of pregnancy and in one outbreak erratic feeding. Skeletal and cardiac myodegeneration were observed grossly and histologically but an almost full term fetus from an affected cow showed no muscle lesions. A high incidence of retained placentae was also recorded.     

Pharmacokinetics of sulphadiazine-trimethoprim in lactating dairy cows

Five Finnish Ayrshire cows in mid or end-lactation were treated with 40 mg sulphadiazine/kg and 8 mg trimethoprim/kg using intravenous (i.v.), intramuscular (i.m.) and subcutaneous (s.c.) routes. Elimination of sulphadiazine was not affected by the route of administration (median t1/2 4.4-5.0 h) while elimination of trimethoprim was strongly limited by slow absorption from the injection site after s.c. and i.m. administration (median for apparent t1/2 21-25 h) compared to that after i.v. administration (median t1/2 1.2 h; p < 0.05). The median bioavailability of trimethoprim was also decreased, being 37% and 55% after s.c. and i.m. administration, respectively. When i.v. administration was used, trimethoprim concentration exceeded 0.1 mg/l in milk between 0.15-8 h while sulphadiazine concentrations above 2 mg/l were maintained from 0.5-2 h to 8 h. After s.c. and i.m. administration sulphadiazine in milk behaved similar to that after i.v. administration, while trimethoprim time-concentration curves were flat and trimethoprim concentrations were around 0.1 mg/l for an extended period of time (8-12 h). Median Cmax values in milk were only 0.07 mg/l and 0.10 mg/l for s.c. and i.m. administrations, respectively. After s.c. administration, 4 out of 5 cows showed signs of pain. After i.m. administration, 2 of the cows showed clear signs of pain and one had some local tenderness at the site of injection.     

Urinary pseudouridine excretion in lactating dairy cows

Introduction   A number of systems based on metabolizable protein, such as that adopted in the UK (A gricultural and F ood R esearch C ouncil 1992) have been developed to improve the accuracy of protein rationing for ruminants. Quantification of microbial protein synthesis in the rumen is a fundamental requirement of all such systems. In the UK system, microbial protein supply is predicted from an estimate of fermentable metabolizable energy intake, using a correction for the effects of level of feeding on the energetic efficiency of microbial protein synthesis. Use of such an approach is however subject to considerable error due to large variations in the energetic efficiency of microbial protein synthesis (A gricultural R esearch C ouncil 1984). Consequently there is an urgent requirement for an on-farm diagnostic marker of microbial protein supply as a basis for adjusting diets to maximize efficiency of dietary nitrogen utilization by dairy cows (D ewhurst et al. 1996). Urinary purine derivative excretion has been proposed as a noninvasive index of microbial protein supply in ruminant animals (T opps and E lliot 1965). Use of this microbial marker is based on the assumption that purines entering the duodenum are essentially microbial in origin (M c A llan 1982), and that following metabolism, their derivatives are quantitatively recovered in the urine (C hen et al. 1990; V erbic et al. 1990). Purine metabolites excreted in ruminant urine are primarily derived from the metabolism of absorbed purines, but as a consequence of tissue adenosine triphosphate and nucleic acid turnover, a proportion of purine bases are not salvaged and re-utilized, but enter catabolic pathways, constituting an endogenous loss.     

Pharmacokinetics of sodium cephapirin in lactating dairy cows

Sodium cephapirin was administered (10 mg/kg of body weight, IM) at 8-hour intervals in 4 consecutive doses to each of 6 lactating dairy cows. Blood, normal milk, mastitic milk, urine, and endometrial tissue samples were collected serially. Mean peak cephapirin concentrations in serum were 13.3 micrograms/ml 10 minutes after the 1st injection and were 15.8 micrograms/ml 20 minutes after the 4th injection (post[initial]injection hour [PIH] 24.33). The overall elimination rate constant value was 0.66/h and plasma clearance was 760 ml/h/kg. Mean peak cephapirin concentration in normal milk was 0.11 microgram/ml at PIH 2 and mean peak cephapirin concentration in mastitic milk was 0.18 microgram/ml at PIH 4. Cephapirin was not detected in the endometrium. The highest concentration of cephapirin in urine was 452 micrograms/ml, 2 hours after the 4th dose (PIH 26).     

Fractional excretion of electrolytes in lactating dairy cows.

Samples of serum and urine were obtained simultaneously from 56 healthy lactating cows to determine ranges of fractional excretion (FE) of calcium (Ca), phosphate (PO4), magnesium (Mg), sodium (Na), potassium (K), and chloride (Cl). Samples were obtained at 3 stages of lactation: period 1 = 1 to 7 days, 2 = 83 to 112 days, and 3 = 175 to 197 days. The FE of electrolytes were significantly different among periods 1, 2, and 3 for Ca (P less than 0.001), PO4 (P less than 0.025) and Mg (P less than 0.025), but were not significantly different for Na, K, and Cl. Least squares mean FE of Ca was lowest in period 1 and not significantly different for periods 2 and 3, whereas mean FE values for PO4 and Mg were highest in period 2 and not significantly different for periods 1 and 3. The mean FE values of Na, K, and Cl did not change with stage of lactation. Age and category of milk production (high, medium, and low) did not influence the FE values of the electrolytes.     

An outbreak of dictyocaulosis in lactating cows on a dairy farm

CASE DESCRIPTION: The owner of a herd of 74 Holstein-Friesian cattle reported decreased milk production, weight loss, and coughing among lactating cows. Owner-initiated antimicrobial treatment was unsuccessful; 1 lactating cow died, and 50% of the lactating cows had clinical signs of respiratory distress, such as tachypnea and coughing. CLINICAL FINDINGS: On the basis of history, physical examination findings, and fecal examination results, affected animals were determined to have Dictyocaulus viviparus (lungworm) infestation. The disease history suggested that the herd contained cows with subclinical patent lungworm infestations; after introduction of susceptible heifers, the pastures had become heavily infested with D viviparus and clinical problems subsequently developed in both newly introduced and resident cows. TREATMENT AND OUTCOME: Affected and unaffected heifers and adult cows were treated with a pour-on formulation of eprinomectin (0.5 mg/kg [0.23 mg/lb]). One animal died, but 2 weeks after treatment, clinical signs among affected cattle were markedly improved. Ten weeks after treatment, milk production improved from 23 kg/cow/d (51 lb/cow/d) to 28 kg/cow/d (62 lb/cow/d). CLINICAL RELEVANCE: The outbreak provides additional evidence that dictyocaulosis is becoming more common among adult dairy cattle, rather than almost exclusively affecting young stock. This may be attributable to anthelmintic use and management practices on dairy farms. Combined with anecdotal reports of an increase in the incidence of dictyocaulosis among adult cattle in North America, D viviparus infestation should be included as a differential diagnosis for decreased milk production, weight loss, and coughing among adult dairy cattle.