Lactation curves for milk yield, fat and protein content in Slovenian dairy sheep
Lactation curves for daily milk yield, fat, and protein content in three dairy sheep breeds were estimated by the repeatability animal model using test-day records. A total of 38 983 records from 3068 ewes of Bovec, Improved Bovec, and Istrian Pramenka breeds, collected between the years 1994 and 20...
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| Format: | Article |
| Language: | English |
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Czech Academy of Agricultural Sciences
2012-05-01
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| Series: | Czech Journal of Animal Science |
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| Online Access: | https://cjas.agriculturejournals.cz/artkey/cjs-201205-0003_lactation-curves-for-milk-yield-fat-and-protein-content-in-slovenian-dairy-sheep.php |
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| author | A. Komprej G. Gorjanc D. Kompan M. Kovač |
| author_facet | A. Komprej G. Gorjanc D. Kompan M. Kovač |
| author_sort | A. Komprej |
| collection | DOAJ |
| description | Lactation curves for daily milk yield, fat, and protein content in three dairy sheep breeds were estimated by the repeatability animal model using test-day records. A total of 38 983 records from 3068 ewes of Bovec, Improved Bovec, and Istrian Pramenka breeds, collected between the years 1994 and 2002, were analysed. The three-trait repeatability animal model included breed and lambing season as fixed. The stage of lactation within each breed was modelled by the modified Ali-Schaeffer's lactation curve. Parity and litter size were used as covariates in quadratic and linear regression, respectively. Common flock environment, additive genetic effect, permanent environment over lactations as well as within lactation were treated as random. The average daily milk yield was 1090 g in Bovec, 1010 g in Improved Bovec, and 731 g in Istrian Pramenka breeds. Overall means for fat and protein content were 6.59 and 5.53% for Bovec, 6.22 and 5.33% for Improved Bovec, and 7.20 and 5.63% for Istrian Pramenka. Breed, lambing season, stage of lactation, parity, and litter size significantly (P < 0.001) affected all three observed milk traits, with the only exception of parity in fat and litter size in protein content. The shape of lactation curves for daily milk yield in Bovec and Improved Bovec breeds fitted well to the general lactation curve in dairy sheep. Daily milk yield was increasing in the first month of lactation and decreasing thereafter. In Istrian Pramenka, the shape of lactation curve was more or less atypical, with daily milk yield decreasing almost throughout the entire lactation. Lactation curves for fat and protein content were opposite to the lactation curves for daily milk yield in all three breeds. |
| first_indexed | 2024-04-10T08:26:14Z |
| format | Article |
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| issn | 1212-1819 1805-9309 |
| language | English |
| last_indexed | 2024-04-10T08:26:14Z |
| publishDate | 2012-05-01 |
| publisher | Czech Academy of Agricultural Sciences |
| record_format | Article |
| series | Czech Journal of Animal Science |
| spelling | doaj.art-86856fc48042420bb03aa689e31dfac52023-02-23T03:33:00ZengCzech Academy of Agricultural SciencesCzech Journal of Animal Science1212-18191805-93092012-05-0157523123910.17221/5921-CJAScjs-201205-0003Lactation curves for milk yield, fat and protein content in Slovenian dairy sheepA. Komprej0G. Gorjanc1D. Kompan2M. Kovač3Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Domžale, SloveniaDepartment of Animal Science, Biotechnical Faculty, University of Ljubljana, Domžale, SloveniaDepartment of Animal Science, Biotechnical Faculty, University of Ljubljana, Domžale, SloveniaDepartment of Animal Science, Biotechnical Faculty, University of Ljubljana, Domžale, SloveniaLactation curves for daily milk yield, fat, and protein content in three dairy sheep breeds were estimated by the repeatability animal model using test-day records. A total of 38 983 records from 3068 ewes of Bovec, Improved Bovec, and Istrian Pramenka breeds, collected between the years 1994 and 2002, were analysed. The three-trait repeatability animal model included breed and lambing season as fixed. The stage of lactation within each breed was modelled by the modified Ali-Schaeffer's lactation curve. Parity and litter size were used as covariates in quadratic and linear regression, respectively. Common flock environment, additive genetic effect, permanent environment over lactations as well as within lactation were treated as random. The average daily milk yield was 1090 g in Bovec, 1010 g in Improved Bovec, and 731 g in Istrian Pramenka breeds. Overall means for fat and protein content were 6.59 and 5.53% for Bovec, 6.22 and 5.33% for Improved Bovec, and 7.20 and 5.63% for Istrian Pramenka. Breed, lambing season, stage of lactation, parity, and litter size significantly (P < 0.001) affected all three observed milk traits, with the only exception of parity in fat and litter size in protein content. The shape of lactation curves for daily milk yield in Bovec and Improved Bovec breeds fitted well to the general lactation curve in dairy sheep. Daily milk yield was increasing in the first month of lactation and decreasing thereafter. In Istrian Pramenka, the shape of lactation curve was more or less atypical, with daily milk yield decreasing almost throughout the entire lactation. Lactation curves for fat and protein content were opposite to the lactation curves for daily milk yield in all three breeds.https://cjas.agriculturejournals.cz/artkey/cjs-201205-0003_lactation-curves-for-milk-yield-fat-and-protein-content-in-slovenian-dairy-sheep.phpdairy sheepmilk traitstest-day recordslactation curves |
| spellingShingle | A. Komprej G. Gorjanc D. Kompan M. Kovač Lactation curves for milk yield, fat and protein content in Slovenian dairy sheep Czech Journal of Animal Science dairy sheep milk traits test-day records lactation curves |
| title | Lactation curves for milk yield, fat and protein content in Slovenian dairy sheep |
| title_full | Lactation curves for milk yield, fat and protein content in Slovenian dairy sheep |
| title_fullStr | Lactation curves for milk yield, fat and protein content in Slovenian dairy sheep |
| title_full_unstemmed | Lactation curves for milk yield, fat and protein content in Slovenian dairy sheep |
| title_short | Lactation curves for milk yield, fat and protein content in Slovenian dairy sheep |
| title_sort | lactation curves for milk yield fat and protein content in slovenian dairy sheep |
| topic | dairy sheep milk traits test-day records lactation curves |
| url | https://cjas.agriculturejournals.cz/artkey/cjs-201205-0003_lactation-curves-for-milk-yield-fat-and-protein-content-in-slovenian-dairy-sheep.php |
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