Evaluation of the reproductive performance of dairy cows:
Gespeichert in:
1. Verfasser: | |
---|---|
Format: | Abschlussarbeit Buch |
Sprache: | English |
Veröffentlicht: |
Berlin
Köster
2009
|
Ausgabe: | 1. Aufl. |
Schriftenreihe: | Schriftenreihe Agrarwissenschaft
21 |
Schlagworte: | |
Online-Zugang: | Inhaltsverzeichnis |
Beschreibung: | VI, 124 S. graph. Darst. |
ISBN: | 9783895746789 |
Internformat
MARC
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245 | 1 | 0 | |a Evaluation of the reproductive performance of dairy cows |c Mahmoud Abdel-Fattah Ibrahim Mohamed El-Sysy |
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264 | 1 | |a Berlin |b Köster |c 2009 | |
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650 | 7 | |a cattle |2 cabt | |
650 | 7 | |a cows |2 cabt | |
650 | 7 | |a dairy cows |2 cabt | |
650 | 7 | |a reviews |2 cabt | |
650 | 7 | |a reproduction |2 cabt | |
650 | 7 | |a reproductive performance |2 cabt | |
650 | 7 | |a female fertility |2 cabt | |
650 | 7 | |a genes |2 cabt | |
650 | 7 | |a calving |2 cabt | |
650 | 7 | |a milk yield |2 cabt | |
650 | 7 | |a calving interval |2 cabt | |
650 | 7 | |a traits |2 cabt | |
650 | 7 | |a phenotypic correlation |2 cabt | |
650 | 7 | |a heritability |2 cabt | |
650 | 7 | |a statistical analysis |2 cabt | |
650 | 7 | |a fertility |2 cabt | |
650 | 7 | |a conception |2 cabt | |
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Datensatz im Suchindex
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adam_text | Titel: Evaluation of the reproductive performance of dairy cows
Autor: Sysy, Mahmoud Abdel-Fattah Ibrahim Mohamed el-
Jahr: 2009
I
Table of Contents
List of tables............................................................................................................Ill
List of figures ...........................................................................................................IV
List of abbreviations................................................................................................VI
1 Introduction.......................................................................................................1
2 Literature review...............................................................................................3
2.1 General Introduction..............................................................................................3
2.2 Physiology of postpartum dairy cows...................................................................3
2.3 Interaction between nutritional management and reproductive performance.......6
2.3.1 Nutrition and ovarian activity in lactating dairy cows..................................6
2.3.2 Relationship of negative energy balance (NEBAL) to fertility.....................8
2.3.3 Dietary protein intake and reproductive performance.................................10
2.4 Relationship between metabolic load, genetic merit and fertility.......................II
2.5 Correlations between fertility and milk production.............................................13
2.6 Interaction between environmental management and reproductive performance 15
2.6.1 Physiological relationship of environmental stress to reproduction............15
2.7 Management factors and reproductive decline in dairy cows.............................17
2.8 Factors affecting age at first calving....................................................................18
2.9 Factors affecting days to first service..................................................................21
2.10 Factors affecting number of services per conception..........................................24
2.11 Factors affecting days open.................................................................................26
2.12 Factors affecting calving interval........................................................................30
2.13 Factors affecting 90-days non-return rate............................................................32
2.14 Genetic parameters..............................................................................................34
2.14.1 Heritabilities................................................................................................34
2.14.2 Genetic and phenotypic correlation.............................................................37
3 Material and Methods.....................................................................................41
3.1 Data source..........................................................................................................41
3.2 Statistical analysis...............................................................................................44
3.3 Estimation of Genetic Parameters.......................................................................46
4 Results.............................................................................___...................___...47
4.1 Factors affecting reproductive traits....................................................................47
4.1.1 Age at first calving......................................................................................47
II
4.1.2 Days to first service.....................................................................................50
4.1.3 Days open....................................................................................................54
4.1.4 Number of services per conception.............................................................58
4.1.5 Calving interval...........................................................................................62
4.1.6 90-d non-return rate.....................................................................................67
4.2 Genetic parameters..............................................................................................70
5 Discussion.........................................................................................................72
5.1 Factors affecting reproductive traits....................................................................72
5.1.1 Age at first calving......................................................................................72
5.1.2 Days to first service.....................................................................................74
5.1.3 Days open....................................................................................................76
5.1.4 Calving interval...........................................................................................78
5.1.5 Number of services per conception.............................................................82
5.1.6 90-day Non-return rate................................................................................84
5.2 Genetic parameters..............................................................................................86
6 Conclusions......................................................................................................89
7 Summary..........................................................................................................91
8 Zusammenfassung...........................................................................................94
9 References.........................................................................................................98
10 Acknowledgements........................................................................................123
Ill
List of tables
Table 1: A review of recent literature regarding age at first calving.......................19
Table 2: A review of recent literature regarding days to first service......................22
Table 3: A review of recent literature regarding number of services per conception
...........................................................................................................................25
Table 4: A review of recent literature regarding days open.....................................27
Table 5: A review of recent literature regarding calving interval............................31
Table 6: A review of recent literature regarding 90-d non-return rate.....................33
Table 7: A review of recent literature regarding heritability (h2) for fertility traits 36
Table 8: Characteristics of the datasets throughout first to fourth lactation............42
Table 9: Number of records, mean, and standard deviations (SD) for studied traits42
Table 10: Analysis of variance for factors affecting age at first calving.................48
Table 11: Least squares means and standard errors of age at first calving..............49
Table 12: Analysis of variance for factors affecting days to first service................51
Table 13: Least squares means and standard errors for factors affecting days to first
service...............................................................................................................52
Table 14: Analysis of variance for factors affecting days open...............................55
Table 15: Least squares means and standard errors for days open..........................56
Table 16: Analysis of variance for number of services per conception...................59
Table 17: Least squares means and standard errors of number of services per
conception.........................................................................................................60
Table 18: Analysis of variance for factors affecting calving interval......................63
Table 19: Least squares means and standard errors of calving interval...................64
Table 20: Analysis of variance for factors affecting 90-d non-return rate...............68
Table 21: Least squares means and standard errors of 90-d non-return rate............69
Table 22: Heritability estimates of studied traits......................................................70
Table 23: Genetic (above the diagonal) and phenotypic (below the diagonal)
correlations between the fertility traits..............................................................71
rv
List of figures
Figure 1: Environmental, management, genetic factors and production performance
affecting fertility traits.......................................................................................44
Figure 2: Distribution of age at first calving.............................................................47
Figure 3: Trend in age at first calving over the years in the German Holstein cows
(in Brandenburg), 1995-2003............................................................................48
Figure 4: Distribution of days to first service...........................................................50
Figure 5: Trend in days to first service over the years in the German Holstein cows
of Brandenburg..................................................................................................50
Figure 6: Means of days to first service by milk yield for Holstein-Friesian of
Brandenburg......................................................................................................53
Figure 7: Means of DFS by milk fat to protein ratio for Holstein-Friesian of
Brandenburg......................................................................................................53
Figure 8: Days open distribution for Holstein-Friesian in Brandenburg (1998-2003)
...........................................................................................................................54
Figure 9: Trend in days open over the years in the German Holstein cow in
Brandenburg (1998-2003).................................................................................54
Figure 10: Means of days open versus lactation number.........................................55
Figure 11: Estimated days open (d) at four scores of calving ease..........................57
Figure 12: Means of days open by milk yield for Holstein-Friesian in Brandenburg
...........................................................................................................................57
Figure 13: NSC distribution for Holstein-Friesian of Brandenburg (1998-2003)...58
Figure 14: Trend in number of services per conception over the years in German-
Holstein cows of Brandenburg (1998-2003).....................................................58
Figure 15: Estimated number of services per conception at four lactations of
Holstein-Friesian in Brandenburg.....................................................................61
Figure 16: Means of NSC by milk yield for Holstein-Friesian in Brandenburg......61
Figure 17: Calving interval distribution for Holstein-Friesian in Brandenburg (1998-
2003)..................................................................................................................62
Figure 18: Trend in calving interval over the years in the Holstein-Friesian of
Brandenburg (1998-2003).................................................................................63
V
Figure 19: Estimated calving interval at four lactations of Holstein-Friesian in
Brandenburg......................................................................................................65
Figure 20: Estimated calving interval (d) at four scores of calving ease.................65
Figure 21: Means of CI by production level of milk yield for the Holstein-Friesian
in Brandenburg..................................................................................................66
Figure 22: Estimated calving interval (d) at three classes of dry period..................66
Figure 23: 90-d NRR distribution for Holstein-Friesian in Brandenburg................67
Figure 24: 90-d NRR trend over the years (1998-2003) in the Brandenburger
Holstein-Friesian...............................................................................................67
Figure 25: Estimated 90-d non-return rate (%) at four scores of calving ease.........70
Figure 26: Graphical illustration of the fertility traits..............................................71
|
any_adam_object | 1 |
author | Sysy, Mahmoud Abdel-Fattah Ibrahim Mohamed el- 1968- |
author_GND | (DE-588)138163944 |
author_facet | Sysy, Mahmoud Abdel-Fattah Ibrahim Mohamed el- 1968- |
author_role | aut |
author_sort | Sysy, Mahmoud Abdel-Fattah Ibrahim Mohamed el- 1968- |
author_variant | m a f i m e s mafime mafimes |
building | Verbundindex |
bvnumber | BV025561940 |
classification_rvk | ZD 32110 |
ctrlnum | (OCoLC)391496240 (DE-599)BVBBV025561940 |
dewey-full | 636.2142 |
dewey-hundreds | 600 - Technology (Applied sciences) |
dewey-ones | 636 - Animal husbandry |
dewey-raw | 636.2142 |
dewey-search | 636.2142 |
dewey-sort | 3636.2142 |
dewey-tens | 630 - Agriculture and related technologies |
discipline | Agrar-/Forst-/Ernährungs-/Haushaltswissenschaft / Gartenbau |
edition | 1. Aufl. |
format | Thesis Book |
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spelling | Sysy, Mahmoud Abdel-Fattah Ibrahim Mohamed el- 1968- Verfasser (DE-588)138163944 aut Evaluation of the reproductive performance of dairy cows Mahmoud Abdel-Fattah Ibrahim Mohamed El-Sysy 1. Aufl. Berlin Köster 2009 VI, 124 S. graph. Darst. txt rdacontent n rdamedia nc rdacarrier Schriftenreihe Agrarwissenschaft 21 Zugl.: Berlin, Humboldt-Univ., Diss., 2009 cattle cabt cows cabt dairy cows cabt reviews cabt reproduction cabt reproductive performance cabt female fertility cabt genes cabt calving cabt milk yield cabt calving interval cabt traits cabt phenotypic correlation cabt heritability cabt statistical analysis cabt fertility cabt conception cabt Zuchtleistung (DE-588)4212022-6 gnd rswk-swf Milchkuh (DE-588)4169916-6 gnd rswk-swf (DE-588)4113937-9 Hochschulschrift gnd-content Milchkuh (DE-588)4169916-6 s Zuchtleistung (DE-588)4212022-6 s DE-604 Schriftenreihe Agrarwissenschaft 21 (DE-604)BV010211734 21 HBZ Datenaustausch application/pdf http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&local_base=BVB01&doc_number=020161251&sequence=000004&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA Inhaltsverzeichnis |
spellingShingle | Sysy, Mahmoud Abdel-Fattah Ibrahim Mohamed el- 1968- Evaluation of the reproductive performance of dairy cows Schriftenreihe Agrarwissenschaft cattle cabt cows cabt dairy cows cabt reviews cabt reproduction cabt reproductive performance cabt female fertility cabt genes cabt calving cabt milk yield cabt calving interval cabt traits cabt phenotypic correlation cabt heritability cabt statistical analysis cabt fertility cabt conception cabt Zuchtleistung (DE-588)4212022-6 gnd Milchkuh (DE-588)4169916-6 gnd |
subject_GND | (DE-588)4212022-6 (DE-588)4169916-6 (DE-588)4113937-9 |
title | Evaluation of the reproductive performance of dairy cows |
title_auth | Evaluation of the reproductive performance of dairy cows |
title_exact_search | Evaluation of the reproductive performance of dairy cows |
title_full | Evaluation of the reproductive performance of dairy cows Mahmoud Abdel-Fattah Ibrahim Mohamed El-Sysy |
title_fullStr | Evaluation of the reproductive performance of dairy cows Mahmoud Abdel-Fattah Ibrahim Mohamed El-Sysy |
title_full_unstemmed | Evaluation of the reproductive performance of dairy cows Mahmoud Abdel-Fattah Ibrahim Mohamed El-Sysy |
title_short | Evaluation of the reproductive performance of dairy cows |
title_sort | evaluation of the reproductive performance of dairy cows |
topic | cattle cabt cows cabt dairy cows cabt reviews cabt reproduction cabt reproductive performance cabt female fertility cabt genes cabt calving cabt milk yield cabt calving interval cabt traits cabt phenotypic correlation cabt heritability cabt statistical analysis cabt fertility cabt conception cabt Zuchtleistung (DE-588)4212022-6 gnd Milchkuh (DE-588)4169916-6 gnd |
topic_facet | cattle cows dairy cows reviews reproduction reproductive performance female fertility genes calving milk yield calving interval traits phenotypic correlation heritability statistical analysis fertility conception Zuchtleistung Milchkuh Hochschulschrift |
url | http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&local_base=BVB01&doc_number=020161251&sequence=000004&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA |
volume_link | (DE-604)BV010211734 |
work_keys_str_mv | AT sysymahmoudabdelfattahibrahimmohamedel evaluationofthereproductiveperformanceofdairycows |