東華大學圖書館 |

Economic and Production Effects of Bovine Viral Diarrhoea : = Insights from Dairy Systems with and Without Control.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Economic and Production Effects of Bovine Viral Diarrhoea :/
其他題名:	Insights from Dairy Systems with and Without Control.
作者:	Yue, Xiaomei.
面頁冊數:	1 online resource (185 pages)
附註:	Source: Dissertations Abstracts International, Volume: 84-05, Section: B.
Contained By:	Dissertations Abstracts International84-05B.
標題:	Infections. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=29877826click for full text (PQDT)
ISBN:	9798352984413

Economic and Production Effects of Bovine Viral Diarrhoea : = Insights from Dairy Systems with and Without Control.
Yue, Xiaomei.

Economic and Production Effects of Bovine Viral Diarrhoea :Insights from Dairy Systems with and Without Control. - 1 online resource (185 pages)

Source: Dissertations Abstracts International, Volume: 84-05, Section: B.

Thesis (Ph.D.)--Wageningen University and Research, 2022.

Includes bibliographical references

Bovine viral diarrhoea (BVD) is a viral cattle disease that presents in most cattle-raising countries worldwide and is listed by the World Organisation for Animal Health as a notifiable disease (Houe, 1995; Richter et al., 2019; OIE, 2021) Infection of bovine viral diarrhoea virus (BVDV) negatively effects the production and economic performance of the dairy herds. Many countries and regions developed BVDV control or eradication programmes and are at different stages of BVDV control. Therefore, information required for decision making in these countries is different. The overall objective of this thesis was to determine the effects of BVDV infection on the production and economic performance of dairy herds in order to support decision making in countries with and without a systematic BVDV control programme. A systematic BVDV control programme is identified by three central elements: biosecurity, elimination of PI animals and surveillance, as opposed to control attempts without clear objectives and monitoring to assess progress (Lindberg et al., 2006). The Netherlands and China were studied as countries with and without a systematic BVDV control programme, respectively.The overall objective of this thesis was divided into the following five sub-objectives: i. Investigate the economic and production effects of BVDV-free certification in Dutch dairy herds. Determine the effects of a new BVDV introduction on milk yield in BVDV-free herds participating in the Dutch BVDV-free programme. Determine the effects of a new BVDV introduction on herd performance (i.e., somatic cell count (SCC), calving interval (CIV), culling risk (CR), and calf mortality rate (CMR)) in BVDV-free herds participating in the Dutch BVDV-free programme. iv. Investigate the within-herd seroprevalence of BVDV in large dairy herds in North China. ii. V. Simulate the dynamics of BVDV infection and the associated production and economic losses in a large-scale Chinese dairy herd using a bio-economic simulation model.In Chapter 2, the economic (gross margin) and production effects (milk yield, SCC), and CIV) of BVDV-free certification were determined based on longitudinal annual accounting and herd performance data from Dutch dairy herds between 2014 and 2019. The study was designed as a case-control study: case herds were defined as herds where the BVDV status changed from unknown to BVDV-free during the study period, while control herds were BVDV-free during the entire study period. Potential bias between the covariates of the two herd groups was reduced by matching case and control herds using the propensity score matching (PSM) method. To compare the differences between case and control herds before and after BVDV-free Difference-in-Differences certification, time-varying estimation (DID) methodology was used. The results indicate that there were no significant changes in milk yield, SCC, CIV, and gross margin upon BVDV-free certification. There are several possible explanations for the non- significant effects, such as the unknown status for case herds, not knowing the true BVDV infection situation in case herds and not knowing if control measures were implemented in case hers prior to participating in the BVDV-free programme. The effects of BVDV-free certification might have been underestimated, given that the Dutch BVDV control programme became mandatory during the study period, and some of the case herds might have never experienced any BVDV infection.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2023

Mode of access: World Wide Web

ISBN: 9798352984413Subjects--Topical Terms:

1621997
Infections.
Index Terms--Genre/Form:

542853
Electronic books.

Economic and Production Effects of Bovine Viral Diarrhoea : = Insights from Dairy Systems with and Without Control.
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245 1 0 $a Economic and Production Effects of Bovine Viral Diarrhoea : $b Insights from Dairy Systems with and Without Control.
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500 $a Source: Dissertations Abstracts International, Volume: 84-05, Section: B.
500 $a Advisor: Hogeveen, H. ; van der Voort, M. ;Steeneveld, W.
502 $a Thesis (Ph.D.)--Wageningen University and Research, 2022.
504 $a Includes bibliographical references
520 $a Bovine viral diarrhoea (BVD) is a viral cattle disease that presents in most cattle-raising countries worldwide and is listed by the World Organisation for Animal Health as a notifiable disease (Houe, 1995; Richter et al., 2019; OIE, 2021) Infection of bovine viral diarrhoea virus (BVDV) negatively effects the production and economic performance of the dairy herds. Many countries and regions developed BVDV control or eradication programmes and are at different stages of BVDV control. Therefore, information required for decision making in these countries is different. The overall objective of this thesis was to determine the effects of BVDV infection on the production and economic performance of dairy herds in order to support decision making in countries with and without a systematic BVDV control programme. A systematic BVDV control programme is identified by three central elements: biosecurity, elimination of PI animals and surveillance, as opposed to control attempts without clear objectives and monitoring to assess progress (Lindberg et al., 2006). The Netherlands and China were studied as countries with and without a systematic BVDV control programme, respectively.The overall objective of this thesis was divided into the following five sub-objectives: i. Investigate the economic and production effects of BVDV-free certification in Dutch dairy herds. Determine the effects of a new BVDV introduction on milk yield in BVDV-free herds participating in the Dutch BVDV-free programme. Determine the effects of a new BVDV introduction on herd performance (i.e., somatic cell count (SCC), calving interval (CIV), culling risk (CR), and calf mortality rate (CMR)) in BVDV-free herds participating in the Dutch BVDV-free programme. iv. Investigate the within-herd seroprevalence of BVDV in large dairy herds in North China. ii. V. Simulate the dynamics of BVDV infection and the associated production and economic losses in a large-scale Chinese dairy herd using a bio-economic simulation model.In Chapter 2, the economic (gross margin) and production effects (milk yield, SCC), and CIV) of BVDV-free certification were determined based on longitudinal annual accounting and herd performance data from Dutch dairy herds between 2014 and 2019. The study was designed as a case-control study: case herds were defined as herds where the BVDV status changed from unknown to BVDV-free during the study period, while control herds were BVDV-free during the entire study period. Potential bias between the covariates of the two herd groups was reduced by matching case and control herds using the propensity score matching (PSM) method. To compare the differences between case and control herds before and after BVDV-free Difference-in-Differences certification, time-varying estimation (DID) methodology was used. The results indicate that there were no significant changes in milk yield, SCC, CIV, and gross margin upon BVDV-free certification. There are several possible explanations for the non- significant effects, such as the unknown status for case herds, not knowing the true BVDV infection situation in case herds and not knowing if control measures were implemented in case hers prior to participating in the BVDV-free programme. The effects of BVDV-free certification might have been underestimated, given that the Dutch BVDV control programme became mandatory during the study period, and some of the case herds might have never experienced any BVDV infection.
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650 4 $a Infections. $3 1621997
650 4 $a Dairy cattle. $3 665493
650 4 $a Diarrhea. $3 853056
650 4 $a Dairy farms. $3 3686790
650 4 $a Mortality. $3 533218
650 4 $a Decision making. $3 517204
650 4 $a Algorithms. $3 536374
650 4 $a Surveillance. $3 3559358
650 4 $a Milk production. $3 665496
650 4 $a Serology. $3 3704150
650 4 $a Certification. $3 1327908
650 4 $a Agriculture. $3 518588
650 4 $a Animal sciences. $3 3174829
650 4 $a Computer science. $3 523869
655 7 $a Electronic books. $2 lcsh $3 542853
690 $a 0473
690 $a 0475
690 $a 0984
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710 2 $a Wageningen University and Research. $3 3557914
773 0 $t Dissertations Abstracts International $g 84-05B.
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