Genetisk variation i brunststyrka hos svenska mjölkkor
When cows in Sweden are inseminated the heat strength is reported to the Swedish milk-recording scheme and AI scheme. Cows that show strong signs of estrus are desirable and the trait is included in the Swedish breeding goal. A strong heat makes it easier to inseminate at the right time and to avoid...
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| Format: | Otro |
| Language: | Swedish Swedish |
| Published: |
2006
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| Subjects: | |
| Online Access: | https://stud.epsilon.slu.se/11094/ |
| _version_ | 1855571806677630976 |
|---|---|
| author | Hedberg, Ann-Sofie |
| author_browse | Hedberg, Ann-Sofie |
| author_facet | Hedberg, Ann-Sofie |
| author_sort | Hedberg, Ann-Sofie |
| collection | Epsilon Archive for Student Projects |
| description | When cows in Sweden are inseminated the heat strength is reported to the Swedish milk-recording scheme and AI scheme. Cows that show strong signs of estrus are desirable and the trait is included in the Swedish breeding goal. A strong heat makes it easier to inseminate at the right time and to avoid long and expensive days open. Since ten years the heat strength is scored from one to five by the farmer and reported to the milk-recording scheme and AI scheme. Earlier the score was from one to three and the decision was made by the AI technician.
The genetic parameters for heat intensity have been estimated from data collected before the scoring was changed, but parameters have not been estimated for the new system. The aim of this study was to estimate genetic parameters for heat intensity for possible use in the genetic evaluation. Data collected in the Swedish milk-recording scheme and AI scheme during the years 1997 to 2003 was used in the study which included both Swedish Holstein and Swedish red and white dairy cattle. The results showed that the heritability of the heat intensity is low in dairy cattle; the heritability was around one percent both in the heifer period and in lactation one to three in both breeds. About one fourth of the herds had a standard deviation in the herd of zero for the trait. This indicates that it is common that the scale for scoring the heat intensity is not used in a proper way when judging the cows' heat intensity. The correlation between lactations for heat intensity was high while it was lower between the heifer period and first lactation. |
| format | Otro |
| id | RepoSLU11094 |
| institution | Swedish University of Agricultural Sciences |
| language | Swedish swe |
| publishDate | 2006 |
| publishDateSort | 2006 |
| record_format | eprints |
| spelling | RepoSLU110942017-09-29T08:22:50Z https://stud.epsilon.slu.se/11094/ Genetisk variation i brunststyrka hos svenska mjölkkor Hedberg, Ann-Sofie Animal genetics and breeding When cows in Sweden are inseminated the heat strength is reported to the Swedish milk-recording scheme and AI scheme. Cows that show strong signs of estrus are desirable and the trait is included in the Swedish breeding goal. A strong heat makes it easier to inseminate at the right time and to avoid long and expensive days open. Since ten years the heat strength is scored from one to five by the farmer and reported to the milk-recording scheme and AI scheme. Earlier the score was from one to three and the decision was made by the AI technician. The genetic parameters for heat intensity have been estimated from data collected before the scoring was changed, but parameters have not been estimated for the new system. The aim of this study was to estimate genetic parameters for heat intensity for possible use in the genetic evaluation. Data collected in the Swedish milk-recording scheme and AI scheme during the years 1997 to 2003 was used in the study which included both Swedish Holstein and Swedish red and white dairy cattle. The results showed that the heritability of the heat intensity is low in dairy cattle; the heritability was around one percent both in the heifer period and in lactation one to three in both breeds. About one fourth of the herds had a standard deviation in the herd of zero for the trait. This indicates that it is common that the scale for scoring the heat intensity is not used in a proper way when judging the cows' heat intensity. The correlation between lactations for heat intensity was high while it was lower between the heifer period and first lactation. Vid inseminering av mjölkkor i Sverige rapporteras brunststyrkan till kokontrollen och seminbokföringen. Kor som tydligt visar brunst är eftersträvansvärda och egenskapen finns med i det svenska avelsmålet. En tydlig brunst gör det lättare att hitta rätt tidpunkt för inseminering och därmed kan långa och kostsamma tomperioder undvikas. Brunststyrkan bedöms av djurägaren och rapporteras sedan ungefär tio år tillbaka utifrån en femgradig skala. Tidigare var skalan tregradig och brunsten bedömdes av seminören i samråd med djurägaren. Skattningar av de genetiska parametrarna för brunststyrka har gjorts utifrån den gamla tregradiga skalan, men sedan skalan gjordes om har inga nya genetiska parametrar skattats. Syftet med den här studien var att skatta nya genetiska parametrar för brunststyrka för eventuell användning i avelsvärderingen. Data insamlade via kokontrollen under åren 1997- 2003 användes i studien som omfattade både SLB och SRB. Resultaten visade att arvbarheten för brunststyrka hos mjölkkor var låg. I kvigperioden och laktation ett till tre var arvbarheten omkring en procent. Runt en fjärdedel av besättningarna hade noll i standardavvikelse inom besättning för den inrapporterade brunststyrkan. Det tyder på att det är vanligt att skalan inte utnyttjas vid bedömning av brunsten. Korrelationen mellan laktationer för brunststyrka var hög medan den var lägre mellan kvigperiod och första laktation, vilket tyder på att fruktsamheten som kviga och ko är olika egenskaper. 2006-10-31 Other NonPeerReviewed application/pdf sv https://stud.epsilon.slu.se/11094/1/hedberg_a_170929.pdf Hedberg, Ann-Sofie, 2005. Genetisk variation i brunststyrka hos svenska mjölkkor. UNSPECIFIED, Uppsala. Uppsala: (VH) > Dept. of Animal Breeding and Genetics (until 231231) <https://stud.epsilon.slu.se/view/divisions/OID-670.html> urn:nbn:se:slu:epsilon-s-7283 swe |
| spellingShingle | Animal genetics and breeding Hedberg, Ann-Sofie Genetisk variation i brunststyrka hos svenska mjölkkor |
| title | Genetisk variation i brunststyrka hos svenska mjölkkor |
| title_full | Genetisk variation i brunststyrka hos svenska mjölkkor |
| title_fullStr | Genetisk variation i brunststyrka hos svenska mjölkkor |
| title_full_unstemmed | Genetisk variation i brunststyrka hos svenska mjölkkor |
| title_short | Genetisk variation i brunststyrka hos svenska mjölkkor |
| title_sort | genetisk variation i brunststyrka hos svenska mjölkkor |
| topic | Animal genetics and breeding |
| url | https://stud.epsilon.slu.se/11094/ https://stud.epsilon.slu.se/11094/ |