DHI analysis of dairy farms in northern Jiangsu province开题报告
2023-02-17 09:57:44
1. 研究目的与意义、国内外研究现状（文献综述）
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The significance of Dairy Herd Improvement(DHI) analysis programme is to provide guideline for appropriate conduct in the production, collection, and distribution of information of all involved records.DHI analysis help dairy producers create and manage records and data about their cows for use in making management decisions.The DHI analysis include services such as milk production,milk fat,milk protein,Somatic Cell Counts(SCC),as well as animal information on birth date, pregnancy, and number of lactation.The amount of data collected, and way it is stored and monitored, makes it a very powerful management tool.
Making decisions about where to spend money in your herd is always easier with the data to support the change.DHI analysis has over the years helped improve the production and management in dairy industries and maximize production.Dairy herd require proper management and each dairy cow must be monitored individual in terms of feed intake,diseases diagnosis,vaccinations and all the necessary day to day management. Most studies conducted on DHI have measured the effect of milking 3X on milk yield and components. Total milk yield is higher from cows milked 3X (Amos et al., 1985; DePeters et al., 1985; Allen et al., 1986; Gisi et al., 1986; Barnes et al., 1990). Higher production from 3X milking is usually expressed as a percentage (Gisi et al., 1986; Campos et al., 1994). However, an analysis of previously published reports found that increasing MF from two times a day (2X) to 3X resulted in a fixed increase of 3.5 kg/d in milk yield and 92 g/day in fat yield independent of parity (Erdman and Varner, 1995). Some studies (Allen et al., 1986; Barnes et al., 1990; Speicher et al., 1994) reported a lower concentration of milk components from cows milked 3X, whereas others (Amos et al., 1985; DePeters et al., 1985) did not report any significant changes. The percentage of CP was lower for cows milked 3X than cows milked 2X during each lactation stage.
REFERENCE Allen, D. B., E. J. DePeters, and R. C. Laben. 1986. Three times a day milking: Effects on milk production, reproductive efficiency, and udder health. J. Dairy Sci. 69:1441–1446. Amos, H. E., T. Kiser, and M. Loewenstein. 1985. Influence of milking frequency on productive and reproductive efficiencies of dairy cows. J. Dairy Sci. 68:732–739. Barnes, M. A., R. E. Pearson, and A. J. Lukes-Wilson. 1990. Effects of milking frequency and selection for milk yield on productive efficiency of Holstein cows. J. Dairy Sci. 73:1603–1611. Butler, W. R., and R. D. Smith. 1989. Interrelationships between energy balance and postpartum function in dairy cattle. J. Dairy Sci. 72:767–783. Campos, M. S., C. J. Wilcox, H. H. Head, D. W. Webb, and J. Hayen. 1994. Effects of production of milking three times daily on first lactation Holstein and Jerseys in Florida. J. Dairy Sci. 77:770– 773. Culotta, C. P., and G. H. Schmidt. 1988. An economic evaluation of three times daily milking of dairy cows. 1988. J. Dairy Sci. 71:1960–1966. DePeters, E. J., N. E. Smith, and J. Acedo-Rico. 1985. Three or two times daily milking of older cows and first lactation cows for entire lactations. J. Dairy Sci. 68:123–132. Erdman, R. A., and M. Varner. 1995. Fixed yield responses to in- creased milking frequency. J. Dairy Sci. 78:1199–1203. Gisi, D. D., E. J. DePeters, and C. L. Pelissier. 1986. Three times daily milking of cows in California dairy herds. J. Dairy Sci. 69:863–868
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2. 研究的基本内容和问题
Dairy Herd Improvement) is the abbreviation of "Cattle Improvement Program". It is also known as the Cow Performance Measurement System in China. It collects milk samples from each lactating cow once a month for testing. The first is to determine the milk performance of cows, including milk yield, milk fat rate, milk protein rate, SCC, urea nitrogen, beta-hydroxybutyric acid and so on. The second is to collect cow feeding. The data of management and management, such as pedigree data, calving date, dry milk date, elimination date and herd structure, are processed systematically, and the results obtained through professional software analysis are returned to the cattle farm to guide the improvement of management and management, and to improve the economic benefits of the pasture. Therefore, the DHI record of dairy cows is also an important basis for ranchers to track the performance of cattle and herds, determine the elimination of cattle, mating, compare between groups, evaluate the balance of feed formulation, mastitis management, ketosis monitoring, selection, cattle trading, veterinary medicine and so on. The DHI Center focuses on performance testing, breed registration, individual genetic evaluation and joint progeny testing of young breed bulls. Through breeding core high-yielding cows, progeny testing, selection of excellent breed bulls and improvement of genetic evaluation method system of breed bulls, the genetic level of dairy cattle Germplasm in Jiangsu Province is improved. After the establishment of Jiangsu Dairy Performance (DHI) Measurement Center, based on Jiangsu Province, we actively promoted the importance of DHI genetic evaluation to dairy farms, and conscientiously implemented the China Dairy Cattle Genetic Improvement Plan (2008-2020) into daily work. Through DHI testing project, the communication between dairy farms and dairy breeding companies, dairy enterprises and consumers is continuously strengthened, which not only helps dairy breeders to strengthen feeding management, improve economic benefits, carry out genetic evaluation and promote dairy herd improvement, but also helps consumers to monitor the quality of fresh milk and improve the quality of life of the residents. Central work received
3. 研究的方法与方案
instructions for the use of dairy analyzer and somatic cell analyzer
1. measuring milk samples
(1) pre-preparation
4. 研究创新点
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Healthy Development of Dairy Industry" (Document No. 31 of National Development [2007] the State Council clearly put forward that "we should make a plan for genetic improvement of dairy cows, do a good job in basic work such as registration of improved breeds and determination of production performance of dairy cows", aiming at speeding up the progress of genetic improvement of dairy cows, improving the quality of dairy cows in Jiangsu Province, improving the economic benefits of dairy farming The industry is developing rapidly and healthily. From the current situation, the DHI determination in Jiangsu Province lags far behind other major dairy producing areas in China. There are nearly 180,000 dairy cows in Jiangsu Province, but only 0.5 million of them are self-checked by enterprises. The 44,000 cows tested by DHI Center of Nanjing Agricultural University are currently included in the national plan. On March 20, 2018, the General Office of the Ministry of Agriculture issued a paper to select the national dairy core breeding farm with DHI descendant detection technology as the core. It is regrettable that there are no dairy enterprises in Jiangsu Province with qualifications. At present, the existing detection institutions in Jiangsu Province are owned by enterprises. The number of cattle measured is very limited. There is no DHI third-party detection institution established. As a result, a large number of aquaculture enterprises need DHI detection to be delivered to institutions outside the province for testing. As a result, most dairy cows in the province can not be scientifically raised and managed on the basis of production performance measurement. In the long run, the DHI ratio of dairy cows was low, which could not play a role in the overall genetic improvement of dairy cows in Jiangsu Province. In addition, Jiangsu Province is located in the Yangtze River Delta region in summer high temperature and humidity, the high temperature period above 26 C lasts for more than three months. However, Holstein dairy cows have poor heat resistance. When the temperature exceeds 26 C, dairy cows will have obvious heat stress reaction, decrease milk yield, decrease disease resistance and increase the incidence of mastitis. Serious cases may lead to an increase in the elimination rate of dairy cows. The core population of heat stress resistant dairy cows will be gradually screened by combining DHI technology with heat stress molecular marker-assisted breeding technology. It is of great significance for the sustainable and healthy development of dairy cow production in Jiangsu.
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5. 研究计划与进展
the research plan is to conduct large data analysis for a pasture in jiangsu province. the specific steps are as follows: 1. preparing for the meadow: 1) collecting basic information of cattle (mainly birth date, pedigree, delivery time, parity, dry milk period, body appearance score, reproduction, etc.) and transmitting milk samples to dhi central laboratory through the network information platform; collection: collection of fresh milk samples is the key to dhi determination, which must be strictly regulated. mixed samples of milk from different shifts on test day (24 hours). total sampling volume per head
for 40 ml (4:3:3 ratio of early, middle and late sampling) milk samples, preservative-added samples can be kept for 4 days when stored, transported and received at 15 c, and for a week when refrigerated (2 7 c).
2: sample detection: 1) incubation at 45 2 debugging milk composition and somatic cell analyzer; 3 on-line detection according to foss machine detection steps. 3: data processing: after the completion of the test, the data were collected from the original record database and imported into the report making software dairy champ and pdhi. the dhi report was completed within 3 working days and sent to the measurements pasture through the information network platform. according to dhi report, we analyzed the situation of cattle in pasture, visited relevant pastures, interpreted the dhi report professionally, and guided the scientific management of pasture, including nutrition regulation, breeding, mastitis management, veterinary medicine and so on.
