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1.
现代规模化、集约化奶牛养殖生产模式下,不断供给高营养水平日粮是维持后备牛快速生长发育和泌乳母牛高泌乳性能的物质基础。然而,在遗传品质到达"瓶颈期"后,尽管随着日粮营养浓度的不断提高和干物质采食量（DMI）的增加,奶牛单产水平可以继续维持在一定的高水平状态,但是高产奶牛的营养代谢性疾病的发病率也呈现快速增长趋势,特别是围产期能量负平衡（negative energy balance,NEB）引起的酮病,高精日粮引发的酸中毒、高蛋白质日粮引起的血液中尿素氮升高等营养代谢性疾病,负调控奶牛繁殖性能,造成奶牛产后发情不明显,配种率和受胎率下降等,直接影响奶牛生产群的更新速度、优质牛群泌乳性能正常发挥以及奶牛养殖的经济效益。作者详细介绍了近年来国内外不同营养代谢性疾病对奶牛繁殖性能影响的相关研究资料,重点分析了酮病、低血钙、瘤胃酸中毒等围产期高发的营养代谢性疾病影响奶牛繁殖性能的分子机制,并对营养代谢性疾病与高产奶牛繁殖性能今后研究的方向提出了展望和思考,以期为提高中国规模化牧场高产奶牛群繁殖效率和母牛围产期营养管理水平提供一定的借鉴和理论依据。  相似文献   

2.
Under the modern large-scale and intensive dairy farming production mode,the continuous supply of feed with high nutrition level is the material basis for maintaining the rapid growth and development of reserve cows and the high lactation performance of lactating cows.However,after the genetic quality reaches the "bottleneck period",although the milk yield of dairy cow can continue to maintain a certain high level with the continuous improvement of the nutrient concentration of feed and the increase of dry matter intake (DMI),the incidence of nutritional metabolic diseases of high-yield dairy cows also shows a rapid growth trend,especially ketosis caused by the negative energy balance in perinatal period,acidosis caused by high-precision diet and the increase of blood urea nitrogen caused by high-protein diet,negatively regulate the reproductive performance of dairy cows,resulting in inconspicuous postpartum estrus,decreased mating rate and conception rate of dairy cows,which directly affect the update speed of dairy cows production groups,the normal performance of high-quality cattle and the economic benefits of dairy farming.In this paper,the author introduced in detail the relevant research on the current situation and its mechanism influence of different nutritional metabolic diseases on the reproductive performance of dairy cows in recent years,and focused on analyzing the molecular mechanism of nutritional and metabolic diseases with high perinatal incidence such as ketosis,low blood calcium and moderate gastric acid,and put forward the prospect and thinking on the future research direction of nutritional and metabolic diseases and reproductive performance of high-yielding dairy cows,in order to provide some reference and theoretical basis for improving the reproductive efficiency of high-yielding dairy cows in large-scale pastures in China and the perinatal nutrition management level of dairy cows.  相似文献   

3.
为了研究裹包全混合日粮(TMR)饲喂方式对泌乳奶牛生产性能、养分表观消化率和血液指标的影响,本试验选择24头泌乳天数为(124±20)d的荷斯坦奶牛,随机分为2个处理组,进行为期10周的饲养试验。对照组采用传统的精粗分开饲喂方式,试验组采用裹包TMR饲喂方式,精粗分开饲喂组和裹包TMR饲喂组的日粮配方组成和比例均相同,日粮精料比例为50∶50,裹包TMR水分含量调整为50%。结果表明,1)饲喂裹包TMR,可以显著增加干物质采食量(P<0.05),提高产奶量7.69%并提高3.5%标准乳产量5.20%(P>0.05);2)裹包TMR饲喂方式与精粗分开饲喂方式对乳成分含量和产量的影响差异不显著;3)裹包TMR饲喂可以显著提高粗蛋白和粗脂肪的表观消化率(P<0.05),干物质消化率有提高的趋势(P<0.1);4)裹包TMR饲喂显著降低了血清中尿素氮的含量(P<0.05),但对其他血液指标影响2组间差异不显著。裹包TMR技术可以作为一种有效的全混合日粮供给方式,可在我国中小规模奶牛养殖场和个体养殖户中推荐使用,以期提高奶牛生产性能和综合收益。  相似文献   

4.
Normal fecal samples were taken from lactating cows fed either a total mixed ration (TMR; n = 30) or pasture‐based diet (20) and from dry cows fed mainly on hay (15). Diarrheic fecal samples (n = 51) were collected from 21 sick dairy cows. Fecal analyses of ammonia, urea, lactate and volatile fatty acid (VFA) levels were used to evaluate colonic fermentation. Most normal feces had reasonably neutral pH, however, alkaline feces were observed in diarrheic cows. Although fecal lactate is higher in cows on grazing pasture, lactate levels were generally lower in the cows in the present study. Fecal VFA levels were higher in lactating cows than in dry cows. Elevated fecal urea was observed in diarrheic cows, however, many fecal samples in normal and diarrheic cows contained no urea. Fecal VFA levels in diarrheic cows were lower than in normal lactating cows, but were approximately equivalent to those in dry cows. Grazing or dry cows showed higher acetate and lower n‐butyrate proportions compared with TMR‐fed or diarrheic cows. Higher proportions of branched chain VFAs were observed in diarrheic cows, and the lowest level was observed in grazing cows. The present results indicate that intracolonic nitrogen equilibrium and proteolytic fermentation are altered by diarrheic status.  相似文献   

5.
Optimal reproduction is very closely tied with optimal nutrition, and early‐lactation diets in cows are critical to successful reproduction and monitoring is important. To evaluate the effects of different dietary protein sources on metabolic parameters and reproductive activity, a total of 36 Italian Friesian early‐lactating dairy cows were assigned for 16 weeks to three dietary treatments as follow: the control diet contained soya bean meal (SBM) as the main protein source, whereas the experimental diets contained faba bean (FB) or pea seeds (PS) as alternative protein sources. Diets were formulated to be isocaloric and isonitrogenous. Cow blood samples were collected, and plasma were analysed for metabolites, biological enzymes, β‐hydroxybutyrate (BHBA) and non‐esterified fatty acids (NEFA). Feeding alternative protein sources had no effects on most metabolic blood profile, except for blood cholesterol, triglycerides and urea. Results from reproductive parameters indicated that cows fed FB diet had a lower insemination index, but a shorter calving to conception period and an improved conception rate and artificial insemination outcome, when compared to cows fed SBM or PS diets. It can be concluded that replacing conventional dietary SBM with alternative protein sources, especially FB, resulted in improved reproductive performances and metabolic parameters in early‐lactating dairy cows.  相似文献   

6.
Citrus pulp is known to contain a functional molecule of beta‐cryptoxanthin which is one of the carotenoids showing anti‐oxidative capacity. Influences of citrus pulp silage feeding to dairy cows on beta‐cryptoxanthin concentration in plasma, other blood properties and milking performances were investigated. Four Holstein cows were fed total mixed ration (TMR) containing citrus pulp silage 20% dry matter (DM) for 2 weeks with free access to the TMR. Dry mater intake, milk production and milk components 2 weeks later were not altered compared with those of the control group without citrus pulp silage. Activities of aspartate aminotransferase, alanin aminotransferase and gamma‐glutamyltranspeptidase in plasma were not affected by feeding of citrus pulp silage. Concentrations of protein, albumin, sulfhydryl residue, ascorbic acid, thio‐barbituric acid reactive substance and urea nitrogen in plasma were also not altered by citrus pulp silage feeding. Concentration of beta‐cryptoxanthin in plasma was increased approximately 20‐fold compared with the control group (P < 0.05). Content of beta‐cryptxanthin in pooled milk fat fraction was also increased approximately three times compared with that of the control group. Feeding of TMR containing citrus pulp silage 15% DM for 30 days to eight dairy cows also increased plasma beta‐cryptoxanthin concentration 30‐fold compared with that before feeding.  相似文献   

7.
The objective of this study was to evaluate the effect of substituting brown rice grain for corn grain in total mixed ration (TMR) silage containing food by‐products on the milk production, whole‐tract nutrient digestibility and nitrogen balance in dairy cows. Six multiparous Holstein cows were used in a crossover design with two dietary treatments: a diet containing 30.9% steam‐flaked corn (corn TMR) or 30.9% steam‐flaked brown rice (rice TMR) with wet soybean curd residue and wet soy sauce cake. Dietary treatment did not affect the dry matter intake, milk yield and compositions in dairy cows. The dry matter and starch digestibility were higher, and the neutral detergent fiber digestibility was lower for rice TMR than for corn TMR. The urinary nitrogen (N) excretion as a proportion of the N intake was lower for rice TMR than for corn TMR with no dietary effect on N secretion in milk and fecal N excretion. These results indicated that the replacement of corn with brown rice in TMR silage relatively reduced urinary N loss without adverse effects on feed intake and milk production, when food by‐products such as soybean curd residue were included in the TMR silage as dietary crude protein sources.  相似文献   

8.
The present study examined the effects of feeding order of grain and protein supplements on ruminal nitrogen (N) loss through the diurnal variation of ruminal ammonia N and urea N in the blood and milk of dairy cows. Three ruminally fistulated cows were used in a 3 × 3 Latin square arrangement of treatments; that is, grain supplement fed at the first feed and then the protein supplement at the second (GS‐1st), protein supplement fed first and then the grain supplement (PS‐1st), and the grain and protein supplements mixed and divided into equal portions fed at each supplement feeding time (GP‐mix). No differences in the lactation parameters were observed among the treatments. In GS‐1st treatment, the increase in the concentration of ruminal ammonia N was inhibited after feeding, and the concentration was lower (P < 0.05) than with the other treatments 1–2 h after basal feeding. The concentrations of urea N in the blood and milk with the GS‐1st treatment were the lowest of all treatments throughout the sampling times, and were lower (P < 0.05) than with the GP‐mix treatment except for blood levels 1 h after basal feeding. The results suggest that grain feeding before protein feeding can reduce ruminal N loss.  相似文献   

9.
In blood serum of dairy cows of the Slovak Pied breed with high and low performance, the levels of total protein, urea, amino nitrogen, non-protein nitrogen and uric acid were studied over the period of four to six weeks after calving. Total protein was determined by the Bio-La-test, amino nitrogen by means of ninhydrin, non-protein nitrogen by Berthelot agent and uric acid by Benedict agent. In comparison with dairy cows with low performance, the dairy cows with high performance had a statistically significantly higher level of total protein, urea, amino nitrogen and non-protein nitrogen. The differences in uric acid content were statistically insignificant.  相似文献   

10.
全混合日粮(total mixed ration,TMR)饲养技术的使用能够保证奶牛摄入均衡的营养,节省大量的人力和物力,并提高奶牛的生产性能,在中国加快推进TMR饲养技术有着重要的现实意义.本文以提高奶牛生产水平,增加养殖者收益为目的,就奶牛生产中使用TMR饲养技术的必要性、奶牛分群及各牛群TMR调配、TMR日粮的制...  相似文献   

11.
影响反刍动物氮素利用效率和排放的营养实践   总被引：1，自引：0，他引：1  
涉及奶牛生产系统和粪肥应用的总氨氮排放参数是影响农业源氨氮排放的最敏感的参数,如何通过精细饲养来提高奶牛的氮素泌乳转化效率,降低奶牛生产系统的氮素排放,对于缓解奶牛生产系统面临的经济与环保双重压力具有重要意义。本文从饲粮的氮素水平、碳水化合物类型、氨基酸补饲、饲料添加剂、饲粮精粗比以及新型饲料原料等方面对影响反刍动物氮素排放的研究进行了综述,同时介绍了康奈尔净碳水化合物-蛋白质体系(CNCPS)模型及其改进对奶牛场氮排放估测的影响以及尿素转运蛋白对反刍动物氮素代谢的影响。  相似文献   

12.
The effect of serum glucose, ASAT and urea on reproductive performance was studied in 45 Finnish dairy cows from 8 different herds. Blood samples were taken a month before calving as well as 2 weeks and 2 months after calving. Serum urea, ASAT and glucose were used as indicators of metabolic and energy balance. Glucose and ASAT concentrations were significantly correlated with fertility 2 weeks after calving, but not before calving or 2 months after calving. Antepartum, 60% of the cows had a low urea level; at 2 weeks and at 2 months postpartum 89% and 65%, respectively had low levels of urea. The cows were divided into groups as follows: low or high (greater than or equal to 2.9 mmol/l) glucose level and low or high (greater than or equal to 2.5 mmol/l) urea level. Low levels of glucose and/or urea in puerperium were associated with poor fertility. The intervals from calving to first insemination and conception were shorter in the group with high glucose and high urea than in the group with low values. The cows with the shortest intervals from calving to first insemination and conception showed adequate metabolic balance (high levels of urea and glucose). Clinical ketosis had an adverse affect on intervals from calving to first insemination and on conception. Intervals from calving to first insemination and to conception were significantly (p less than 0.01) longer in ketotic cows than in non-ketotic ones. Liver damage, reflected as elevated activity of ASAT, was associated with poor fertility. If shorter calving intervals are desired, adequate energy balance in puerperium is essential.  相似文献   

13.
The traditional metabolic profile test cannot be applied to peripartum dairy cows, because these cows are in a state of physiological abnormality making it difficult to interpret their blood components. This study aimed at establishing and evaluating the practicability of interpreting a metabolic profile test every 10 days (Ten-day criteria) during the dry and lactation periods in herds with high and no incidence of peripartum diseases. Data from 29,043 cows in 1,130 commercial dairy herds were used to establish standard values every 10 days, mean +/- 1.0 standard deviation for the metabolic profile test. The practicability of these criteria was evaluated in herds with peripartum diseases. In the ten-day criteria, the body condition score, albumin, blood urea nitrogen, glucose, total cholesterol, nonesterified fatty acids, gamma-glutamyl transpeptidase and aspartate aminotransferase, fluctuated during the dry and early lactation periods and there were very big changes in packed cell volume, blood urea nitrogen, total cholesterol and magnesium just after calving. The ten-day criteria were able to detect overconditioned cows, low levels of albumin, total cholesterol and magnesium, and high nonesterified fatty acids in herds with a high incidence of peripartum diseases. In conclusion, the ten-day criteria can be successfully applied to peripartum cows, and is recommended because it is able to detect metabolic abnormalities not only in the herd, but also in individual cows.  相似文献   

14.
Forty Holstein dairy cows were used to determine the effects of forage feeding system, season and stage of lactation on some blood parameters. Blood urea nitrogen was higher for cows consuming higher levels of crude protein and particularly for the ones on pasture. Hemoglobin and packed cell volume values were correlated with the level of crude protein intake and stage of lactation. Lower values of these parameters were observed with lower crude protein intake and in early lactation. Serum levels of albumin, calcium, inorganic phosphorus, sodium and potassium were not affected either by forage system, season or stage of lactation. Serum magnesium level was lower for forage system containing corn silage. Blood glucose was lower for cows in early lactation but was not affected by feeding systems during winter. Cows on pasture had higher blood glucose levels. Lower total protein concentration in blood was observed between 90 and 180 days of lactation as a result of lower gammaglobulins. Blood parameters are good indicators of nitrogen and energy nutritional status of dairy cows. However, blood mineral concentrations are not related to the level of mineral intake of animals.  相似文献   

15.
为研究饲料中添加复合酵母培养物对奶牛产奶性能、氮排放及血液生化指标的影响,选取年龄、体重、产奶量及泌乳期相近(135±15) d的荷斯坦奶牛24头,随机分为4组,每个处理6个重复,对照组和3个试验组的复合酵母培养物添加量分别为精料浓度的0,0.8%,1.0%,1.2%,随精料饲喂,测定产奶量、乳成分、氮排放及血液生化指标,结果表明,1)试验2组日均产奶量显著高于对照组(P<0.05),各试验组分别比对照组提高8.48%,10.05%,8.97%。2)复合酵母培养物能显著提高乳脂和乳蛋白率(P<0.05),显著降低牛奶体细胞数(P<0.05),以试验2组最低。3)在氮排放量上,试验2组显著低于对照组(P<0.05),各试验组比对照组分别降低8.47%,12.01%,9.36%。4)在血液生化指标方面,复合酵母培养物能提高血清中总蛋白、球蛋白、血糖、胰岛素水平(P<0.05),降低尿素氮水平(P<0.05)。由此可见,本试验条件下,综合考虑产奶量、乳成分、氮排放及血液生化指标,复合酵母培养物的最佳添加量为精料浓度的1.0%。  相似文献   

16.
AIMS: To assess if raising concentrations of crude protein (CP) in pasture in spring by the frequent application of urea fertiliser would affect ovarian follicular dynamics, luteal function, onset of oestrus and reproductive performance of dairy cows under farming conditions in New Zealand. METHODS: Spring-calved dairy cows were grazed for 101 days in paddocks that were either not fertilised (Control; n=20) during the course of the study, or were fertilised with 40-50 kg nitrogen (N)/ha every 4-6 weeks (High-N; n=20). Similar generous pasture allowances were offered to both groups. Concentrations of CP in pasture, urea in serum and progesterone in milk were measured. Ovarian follicular and luteal dynamics were determined using ultrasonography. Oestrous behaviour and the number, time and outcome of inseminations were also recorded. RESULTS: Mean concentrations of CP in pasture and urea in serum was higher in the High-N than the Control group (25.2 vs 21.6 and 8.3 vs 5.4 mmol/L for CP and urea, respectively; p<0.001). Intervals between calving and first oestrus, first insemination and conception, the time of first emergence of a dominant follicle, milk progesterone concentration, and the diameter of the corpus luteum (CL) in the first luteal phase did not differ significantly between groups. The interval from calving to first ovulation tended (p=0.10) to be lower and the diameter of the dominant follicle of the oestrous cycle at which cows conceived was greater (p=0.02) in Control than High-N cows. CONCLUSIONS: The use of large amounts of urea fertiliser during spring and the consequent increases in concentrations of CP in pasture and urea in serum did not negatively affect any of the parameters of reproductive performance of pasture-fed dairy cows that were assessed in this study.  相似文献   

17.
试验旨在探究奶牛自身生理代谢与产奶量(MY)和乳蛋白率(MP)的关系。从饲喂相同日粮的287头经产、泌乳中期荷斯坦奶牛中分别选取高、低MY牛各20头,高、低MP牛各20头,探究血液生化参数和激素水平的差异;结合287头奶牛的MY、MP与血液生化参数、激素的关联结果,挖掘影响MY和MP的关键生理代谢。结果表明:高MY牛血液中总蛋白、白蛋白和总胆固醇浓度高于低MY牛(P<0.05),而血尿素氮、胰高血糖素、胰岛素样生长因子-1和瘦素浓度低于低MY牛(P<0.05);高MP牛的血尿素氮和白蛋白浓度高于低MP牛(P<0.05),高低MP牛的血清激素无显著差异;关联分析显示,上述差异指标中总胆固醇与MY正相关(P<0.01),血尿素氮与MY负相关(P<0.05);血尿素氮与MP正相关(P<0.05),总蛋白与MP负相关(P<0.01)。综上,在相同的日粮和管理条件下,氮代谢在奶牛MY、MP合成中均发挥重要作用,并且MY可能受能量供应和奶牛自身分泌激素的调控。  相似文献   

18.
试验旨在研究中药复方健宫散治疗奶牛子宫炎对部分血液及代谢指标的影响,探讨中药复方对产后子宫炎作用机理,为早期预防奶牛子宫炎提供理论依据。选取年龄、体重和胎次相近的18头奶牛按临床症状、阴道分泌物的性状、B超检查分为3组,患病组(患子宫炎不治疗)、正常组(未患子宫炎)和治疗组(患子宫炎治疗),每组6头。治疗组灌服中药健宫散,患病组与正常组灌服生理盐水。灌药期为7 d。分别于用药前、用药中、用药后1、4、7、11、15、20 d采集血液,通过ELISA方法检测用药前后3组奶牛部分血液及代谢指标。结果表明,健宫散能显著提高血液中的红细胞数、血红蛋白含量、淋巴细胞数(P<0.05),显著降低血液中的白细胞数、粒细胞数、β-羟丁酸、尿素氮、天门冬氨酸转氨酶含量(P<0.05)。由此可见,中药健宫散能调节部分血液和代谢指标,提高机体抗炎、免疫能力,改善机体的代谢功能,更好地预防和治疗子宫炎。  相似文献   

19.
关于推进中国奶牛全混合日粮饲养技术的思考   总被引：4，自引：1，他引：3  
全混合日粮（total mixed ration ,TMR）饲养技术的使用能够保证奶牛摄入均衡的营养,节省大量的人力和物力,并提高奶牛的生产性能,在中国加快推进TMR饲养技术有着重要的现实意义。而中国现阶段奶牛的饲养模式主要以小规模养殖为主,由于缺乏资金和技术支持,大多数中、小型奶牛场、养殖户还不能使用TMR饲喂技术来提高奶牛生产性能。TMR配送服务是由专门的配送公司集中生产不同饲养阶段的TMR日粮,再提供给周边养牛户的一种生产配送形式。此种方式可以使小规模奶牛养殖户也能用到TMR饲喂技术,从而提高奶牛生产水平,增加养殖者收益,并且推进TMR技术在中国的推广和应用。  相似文献   

20.
Recent studies have shown significant associations between prepartum energy status and postpartum fertility in dairy cows; therefore, the assessment of energy status by blood metabolites and metabolic hormones and suitable improvement of management during the prepartum period may enhance reproductive performance. Rumen fill score (RFS) is associated with feed intake; however, it is unknown whether RFS is also related to blood parameters. Therefore, this study investigated the relationship between RFS and energy status during the prepartum period, and their associations with conception at first artificial insemination (AI) after parturition. In 42 multiparous Holstein cows, RFS assessment and blood sampling were carried out twice a week during 3 weeks of the peripartum period. Ovarian cycles until AI were evaluated by measuring milk progesterone levels. Before calving, positive correlations were observed between RFS and total cholesterol, and RFS did not change in pregnant cows at first AI after parturition, whereas in non‐pregnant cows, RFS decreased gradually as the calving day approached. After calving, non‐pregnant cows showed lower energy status compared with pregnant cows, and some non‐pregnant cows showed anovulation and cessation of estrous cycle. In conclusion, RFS during the close‐up dry period is related to real‐time energy status, and is associated with postpartum energy status and conception at first AI in dairy cows. © 2016 Japanese Society of Animal Science  相似文献   

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