美国干奶牛饲养技术

在奶牛的繁殖周期中,干奶期往往是容易被忽视的时期。但是,奶牛营养方面的研究结果表明,干奶期的饲养管理对下一个泌乳期的产奶量及产褥期代谢病的发生等有很大的影响。 1.干奶期长短及干奶方法干奶期以6～8周为宜。为了乳腺组织的再生,体内能量、蛋白质、矿物质的维持和蓄积,至少要保证6周干奶期。如保证不了正常的干奶时间,下一个泌乳期要减少500～900公斤产奶量。干奶期饲养要遵循的基本原则是限制干奶牛过肥。     

干奶牛的干奶及饲养管理方法

我们把进入干奶期的母牛称为干奶牛。通常情况下，即将进入干奶期的母牛的乳腺组织由于经过一个泌乳期的长时间分泌活动，急需有一个周期性的休整，好让乳腺分泌上皮细胞再生、更新，以便为下一个泌乳期能正常泌乳做准备。母牛瘤胃经过泌乳期高水平精料日粮的应激，需要通过饲喂粗饲料来恢复瘤网胃的正常机能。母牛经过长期的泌乳和妊娠，特别是妊娠后期胎儿生长迅速，消耗了母牛体内大量的营养物质，需要干奶期让自身营养亏损得到补充，同时蓄积一定的营养，为下一个泌乳期做准备。干奶期的长短、干奶牛饲养管理的好坏，对母牛腹中胎儿的正常生长、母牛健康以及下一个泌乳期的产奶性能均有重要影响。     

干奶期及泌乳期乳房炎的综合防制

<正>1干奶期乳房炎的防治干奶期是预防和控制产后发生乳房炎的重要时期,干奶期的治疗能使乳房有机会在下一个泌乳期到来之前修复受损的乳腺组织。进入干奶期后停止了挤奶,取消了每日的乳头药浴,乳头     

奶山羊饲养及羔羊哺育技术

奶山羊母羊在不同生理时期和生产时期对营养和管理的要求不同,故将其分为泌乳期和干奶期.不同的时期有不同的饲养管理条件. 1 干奶期的饲养管理 干奶期系指母羊不产奶的时期,奶山羊的干奶期一般为60天左右.此时,母羊刚经过一个泌乳期,体况很差,又正值妊娠后期,胎儿发育正需要大量的营养.     

齐利宁——利福昔明乳房注入剂

正1 研发背景奶牛乳房炎是奶牛场防治难度较大的一种常见性疾病,严重影响奶牛养殖业的发展,是困扰奶业经济效益及迅速发展的的主要制约因素。奶牛干奶期是防控乳房炎的最佳时期,可以有效防治干奶期间以及上一个泌乳期所遗留下来的感染,并且能够显著降低下一个泌乳期乳房炎的发病率,对受损的乳腺组织有机会在下一个泌乳期到来之前得到较好的修复。国内目前用于干奶期奶牛乳房炎防治的药物主要以青霉素类抗生素为主,但随着近十年来国内奶牛乳房     

中草药注射液防治奶牛干奶期乳房炎的作用初探

干奶期是奶牛乳房炎发病率较高的一个时期,其主要原因是干奶前已有潜在感染;同时据报道干奶期中24％健康乳区可受葡萄球菌和链球菌感染,所以产后菌检率高于干奶时的感染。Schultze等指出,停奶前有一个乳区感染者,其余的健康乳区在干奶期中有更高的易感性。新的感染使下次泌乳期第一个月的奶产量可下降36％,而且这些感染约有一半可持续到下次泌乳期,其中又有一半可成为临床型乳房     

高产奶牛干奶需掌握的技术要点

干奶是指奶牛在分娩前停止产奶的过程。干奶时间、干奶期的长短对下一个泌乳期的产奶量影响很大。于奶期过短。对母牛营养物质的贮备、胎儿的发育都不利。会影响正常生产：干奶期过长，则会减少产奶时间和产奶量，不经济。目前，多将干奶期平均定为60天，这对高产奶牛尤为重要。     

高产奶牛干奶需掌握的技术要点

干奶是指奶牛在分娩前停止产奶的过程.干奶时间、干奶期的长短对下一个泌乳期的产奶量影响很大.干奶期过短,对母牛营养物质的贮备、胎儿的发育都不利,会影响正常生产;干奶期过长,则会减少产奶时间和产奶量,不经济.目前,多将干奶期平均定为60天,这对高产奶牛尤为重要.     

奶牛各阶段的饲养管理措施

<正>科学研究发现,每天喝一杯牛奶能够提高人体钙的含量,防止老年人的骨质疏松,增强骨密度和骨硬度,因此,牛奶的需求量不断地上升。奶牛饲养管理的好坏,直接关系到奶牛的产奶量。奶牛的饲养管理在生长中主要分为干奶期、围产期以及泌乳期,而泌乳期又可以分为泌乳早期、泌乳中期、泌乳后期,每一个阶段都有不同的饲养管理措施。1干奶期干奶期是指泌乳牛产犊前2个月左右人为控制不让奶牛产奶的时期。干奶期奶牛不需要提高饲     

选择性干奶期治疗在奶牛场中的应用与关键点控制

奶牛乳房炎是造成奶牛场经济损失最严重的疾病之一,干奶期是治疗奶牛乳房炎的关键时期,干奶期奶牛饲养管理及健康状况将直接影响下一个泌乳期的牛奶品质、产量及奶牛场的经济效益。本文综合阐述了选择性干奶治疗在欧洲、美国等全球奶业发达国家及地区奶牛场中的应用情况,并分析了影响选择性干奶期治疗的管理因素,针对干奶前、干奶期和干奶后期分析了不同阶段的管理操作要点,以期为指导奶牛场实际生产提供参考依据。     

泌乳盛期和泌乳后期奶牛的采食行为和日粮营养物质表观消化率的对比分析

试验旨在研究不同泌乳阶段奶牛饲喂相同日粮对采食行为和日粮营养物质表观消化率的影响。选择体重、胎次相近的8头健康泌乳牛,其中4头处于泌乳盛期(泌乳盛期组),4头处于泌乳后期(泌乳后期组),2组奶牛饲喂相同日粮,预试期15 d,正试期15 d。结果表明:泌乳盛期组奶牛每天干物质采食量(24.0 kg)高于泌乳后期组(P<0.01),泌乳盛期组奶牛每千克干物质的采食时间、一昼夜总反刍时间、躺卧时间均低于泌乳后期组(P<0.01),;泌乳盛期组奶牛日粮中中性洗涤纤维和酸性洗涤纤维的表观消化率低于泌乳后期组(P<0.01)。由此可见,泌乳盛期奶牛采食时间极显著高于泌乳后期奶牛,泌乳盛期奶牛躺卧时间极显著少于泌乳后期。     

缩短哺乳期和早期补饲对晋南牛犊牛增重效果的影响

选用３６头晋南牛初生犊牛，分成试验１组、试验２组和对照组共３组，每组１２头（公母各半），试验组与对照组采用不同的断奶期和精料补饲量，以此来探讨早期断奶和早期补饲对增重的影响。结果表明缩短哺乳期，增加混合精料补饲量比延长哺乳期的效果好。哺乳期相同情况下，增加精料补饲量可取得较好的增重效果。     

泌乳奶牛采食、反刍、逍遥行为和日粮纤维性物质表观消化率对比分析

为了对比不同泌乳阶段奶牛的采食、反刍、逍遥行为和日粮营养物质表观消化率,选择体重、胎次相近的8头健康荷斯坦泌乳奶牛,其中,4头处于泌乳盛期(泌乳盛期组),4头处于泌乳后期(泌乳后期组),进行了采食行为观察和消化试验,两组奶牛预饲期20 d,正试期15 d。结果表明,泌乳盛期组奶牛每天的干物质采食量为21.2 kg,极显著高于泌乳后期组的14.1 kg(P<0.01),但两组奶牛的采食时间和采食次数无显著差异(P>0.05),泌乳盛期组奶牛每千克DM采食的时间也极显著低于泌乳后期组奶牛(P<0.01);一昼夜总反刍时间泌乳盛期组奶牛极显著低于泌乳后期组(P<0.01),每千克DMI需反刍时间泌乳盛期组奶牛极显著低于泌乳后期组(P<0.01)。泌乳盛期组奶牛躺卧、走动和站立时间与泌乳后期组奶牛相比无显著差异(P>0.05)。泌乳盛期组奶牛日粮中NDF和ADF的表观消化率极显著低于泌乳后期组(P<0.01),两组奶牛NDF的表观消化率分别为55.8%、67.8%,ADF的表观消化率分别为44.2%、60.7%。     

Follicular turnover and hormonal association in postpartum goats during early and late lactation

To clarify the effect of lactation period on ovarian follicular activity and associated hormonal levels in goats, six goats were monitored daily by ultrasonographic examination with blood sampling during early (Days 5 to 25; Day 0 was the day of kidding) and late (Days 40 to 60) lactation. While the presence of a corpus luteum of pregnancy retarded follicular growth in the ipsilateral ovary until Days 11-13 postpartum, the total follicular number (TFN) and area (TFA) increased during late lactation due to the significant increase in the number of medium- and large-sized follicles and decrease in the number of small follicles. Four goats showed a similar pattern of follicular development during the period studied characterized by the emergence of five and six waves during the early and late lactation, respectively. The largest follicle diameter of the first three waves monitored during early lactation was significantly smaller as compared with the diameter of those existing during late lactation. TFN showed a positive correlation with FSH but showed a negative correlation with immunoreactive (ir-) inhibin and estradiol during the postpartum period. TFA was positively correlated with ir-inhibin, estradiol and PRL and negatively correlated with FSH during the monitored periods. The plasma levels of ir-inhibin and progesterone were significantly higher during late lactation compared with the levels recorded during early lactation. Ir-inhibin levels showed a significant positive correlation with LH and estradiol during early and late lactation but showed a negative correlation with FSH during the whole lactation period. LH was positively correlated with estradiol and PRL during early and late lactation, respectively. These results suggest that the lactation period has a detrimental effect on ovarian activity during the early postpartum period in goats.     

Relationship between the lactation curve and udder disease incidence in different lactation stages in first‐lactation Holstein cows

We examined the relationships between the shape of the first parity lactation curve and udder disease incidence at different stages of lactation in 538 Holstein cows. Data used were first‐parity daily milk yields and treatment records. Each cow was classified according to whether or not it had had udder disease at least once over the whole lactation period or in one of three stages within the lactation period. We then examined the differences in the shapes of the lactation curves between the disease incidence and non‐incidence group in each stage. Cows that had high rates of increase in milk yield and high milk yields in early lactation were predisposed to udder disease afterwards. Cows with high milk production over a long period but with low lactation persistency were predisposed to udder disease after the peak of lactation. There was no difference in total milk yield between incidence and non‐incidence groups in all stages, suggesting that, for a comparable level of lactation, cows without udder diseases have flatter lactation curves.     

Studies in sow reproduction: 4. The effect of level of feeding in lactation and during the interval from weaning to remating on the subsequent reproductive performance of the early-weaned sow

An investigation of the effects of level of nutrition, both in lactation and from weaning to remating, on subsequent litter size and associated reproductive characteristics in the early-weaned sow is reported. Subjects were 75 sows in 5 groups. In 4 of the groups the sows were weaned after a 10-day lactation period. Group 5 was weaned following a 42-day gestation. The control group was fed up to 6.3 kg/day during lactation and 2.7 kg/day from weaning to remating. The 4 early-weaned groups were each fed differently. In lactation and during the inverval from weaning to remating they were fed either 2 or 4 kg/day. The group receiving only 2 kg/day during each period lost more weight than the others (p less than .05). Weight loss in lactation was significantly (p less than .001) affected by feeding. Sows weaned after a 10-day lactation period farrowed 2.7 piglets/litter less in the next parity than sows weaned after a 6-week lactation period. Weight losses during lactation were not related to subsequent litter size. Level of nutrition from weaning to remating in these tests had no influence on subsequent litter size. The early-weaned sow, even with large fluctuations in weight change over the period from parturition to remating, did not alter their ceiling for litter size. It seems unlikely that ovulation rate is the major factor limiting litter size in the early-weaned sow. Results suggest that embryo mortality following ovulation and coitus is increased in the early-weaned sow and that this effect then manifests itself as a ceiling to subsequent litter size.     

Characterization of ruminal dynamics in Holstein dairy cows during the periparturient period

We used four pregnant Holstein cows to delineate ruminal adaptations as cows transitioned from one lactation to the next. Cows were fed typical diets through far-off and close-up dry periods and lactation. We measured ruminal characteristics on day 72 (late lactation), 51 (far-off dry), 23 and 9 (close-up dry) prepartum and on days 6, 20, 34, 48, 62, 76 and 90 postpartum (early lactation). Measurements included: ruminal fill (weight of actual contents), ruminal capacity (volume of rumen when fully filled), digestibilities and ruminal passage rates. Ruminal capacity tended to increase linearly during early lactation but was stable during dry and transition periods. Both total and liquid fill decreased linearly during the dry period, increased across parturition, and increased linearly through early lactation. Dry matter fill decreased as cows were fed the close-up diet at day 23 prepartum then increased near parturition and continued to increase across early lactation. Solid passage rate was greatest when cows were fed the close-up diet, and decreased throughout the transition period. In lactation, solid passage rate responded quadratically with peak at day 48 followed by decreases through day 90 postpartum. Liquid passage increased linearly across the transition period. Total tract organic matter digestibilities increased linearly over the dry period with significant increases prior to or immediately after parturition, then they remained relatively stable over early lactation until they increased at day 90. Fibre digestibilities demonstrated quadratic responses over early lactation, being higher on day 6 and day 90 than at other times. Starch digestibilities decreased linearly across both the dry and transition periods with decreases in lactation until day 62 followed by increases until day 90. High producing lactating dairy cows go through a multitude of ruminal adaptations, in terms of digestion, passage, capacity and fill, as they transition from one lactation to the next.     

牛奶中脂肪酸与常规营养成分含量的影响因素分析

本试验旨在研究季节对牛奶中脂肪酸含量的影响以及不同地区、泌乳期、季节和胎次对牛奶常规营养成分的影响。对来自DHI中心的9872份牛奶样本中的脂肪酸含量数据和3430份牛奶样本中的乳脂、蛋白质、乳糖与总固形物含量数据,按季节、地区、泌乳期、胎次进行分组,然后进行单因素方差分析。结果如下:(1)季节对牛奶中脂肪酸含量产生极显著影响(P<0.01):夏季乳脂中饱和脂肪酸极显著高于其他季节(P<0.01),不饱和脂肪酸极显著低于其他季节(P<0.01)。游离脂肪酸春季最高且极显著高于其他季节(P<0.01)。(2)不同地区对乳脂、乳糖、总固形物产生极显著影响(P<0.01):宁夏蛋白质含量最高,且显著高于河南、湖北与内蒙古(P<0.05)。而宁夏与内蒙古之间乳脂、乳蛋白、总固形物无显著差异(P>0.05)。湖北与宁夏牛奶总成分含量较高。(3)泌乳期对牛奶成分含量产生极显著影响(P<0.01):泌乳前期乳脂、蛋白质、总固形物含量最低,且显著低于泌乳中期、泌乳晚期、泌乳延长期(>305d)(P<0.05)。泌乳前期与泌乳中期乳糖含量较高,且极显著高于泌乳晚期、泌乳延长期(P<0.01)。(4)不同季节对乳常规营养成分含量产生极显著影响(P<0.01):夏季各项指标最低,且极显著低于春季、秋季、冬季(P<0.01)。(5)不同胎次对乳蛋白、乳糖、总固形物含量产生极显著影响(P<0.01),一胎牛乳中各种成分含量最高,且极显著高于三胎次奶牛(P<0.01)。     

夏季暑热期不同泌乳阶段奶牛维持行为的比较研究

本次试验对15头中国荷斯坦泌乳牛的行为表现逐头进行12 h观察,并按不同泌乳阶段分三组:A组(泌乳前期)、B组(泌乳中期)、C组(泌乳后期)进行分析,每组均为5头。结果表明:泌乳前期牛的咀嚼次数和每次低头连续采食饲料次(口)数最多,早晨饲喂以后反刍来临时间和咀嚼时间最长,反刍咀嚼速度及每次低头采食频率快。泌乳中期试验牛的昼间反刍时间、昼间反刍时间占昼的时间、每次低头采食时间及每口饲料咀嚼时间都较长。泌乳后期试验牛的昼间反刍周期数较多,食团的吞咽至下一食团的逆呕间隔时间和站立时间均较长。