Effect of heat-stress on conception in a dairy-herd model in the Natal highlands of South Africa
| dc.contributor.author | Du Preez, J.H. | |
| dc.contributor.author | Willemse, J.J.C. | |
| dc.contributor.author | Van Ark, H. | |
| dc.contributor.editor | Verwoerd, Daniel Wynand | |
| dc.date.accessioned | 2013-12-09T08:05:28Z | |
| dc.date.available | 2013-12-09T08:05:28Z | |
| dc.date.created | 2013 | |
| dc.date.issued | 1994 | |
| dc.description | The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format. | en |
| dc.description.abstract | Regression models are proposed for predicting conception rate in a dairy herd under South African and especially Natal conditions. Conception rate (CR%) was related to mean monthly temperature-humidity index (THI) by curvilinear regression equation model; CR% = -812,7 + 28,61THI - 0,2322THI² (P = 0,061), and by linear regression equation model; CR% = 188,0 - 1,906THI (P = 0,023). Conception rate was related to numerical month of the year (M) by: CR% = 44,34 + 6,168M - 0,428M² (P = 0,1 06). Further investigations to test the proposed regression models under various dairy-herd conditions and to improve reproduction in South African dairy herds are needed. | en |
| dc.description.librarian | mn2013 | |
| dc.identifier.citation | Du Preez, JH, Willemse, JJC & Van Ark, H 1994, 'Effect of heat-stress on conception in a dairy-herd model in the Natal highlands of South Africa', Onderstepoort Journal of Veterinary Research, vol. 61, no. 1, pp. 1-6. | en |
| dc.identifier.issn | 0330-2465 | |
| dc.identifier.uri | http://hdl.handle.net/2263/32737 | |
| dc.language.iso | en | en |
| dc.publisher | Published by the Agricultural Research Council, Onderstepoort Veterinary Institute | en |
| dc.rights | © ARC-Onderstepoort (original). © University of Pretoria. Dept of Library Services (digital). | en |
| dc.subject | Veterinary medicine | en |
| dc.subject | Friesian cattle | en |
| dc.subject | Lidgetton | en |
| dc.subject.lcsh | Veterinary medicine -- South Africa | |
| dc.subject.lcsh | Heat -- Physiological effect | en |
| dc.title | Effect of heat-stress on conception in a dairy-herd model in the Natal highlands of South Africa | en |
| dc.type | Article | en |