| title: | Morphology and functional characteristics of bovine oocytes and spermatozoa in relation to fertility |
|---|---|
| reg no: | ETF6089 |
| project type: | Estonian Science Foundation research grant |
| status: | accepted |
| institution: | EAU Faculty of Veterinary Science |
| head of project: | Ülle Jaakma |
| duration: | 01.01.2005 - 31.12.2008 |
| description: | The present project represents continuation and development of our previous research work. As a result of the recent studies, we have established that clinical pathology as a reason for repeat breeding was diagnosed only in 1/3 of subfertile cows. The total number and the number of morphologically normal oocytes and embryos were about twice lower in repeat breeders in comparison to fertile cows. When studying bulls' fertility, several significant correlations among single sperm parameters and nonreturn rates of cows and heifers were identified. Changes in basic semen characteristics during bull aging were established. The objectives of the present research project are: 1. To investigate the morphological quality and ultrastructure of oocytes and embryos in relation to hormonal and metabolic profiles and uterine condition in repeat breeding and normal cows. 2. To develop the statistical models based on laboratory testing of sperm functions for the evaluation of bull semen fertility. Specific ultrastructural features of oocytes, resumption of post-partum ovarian activity, relations between metabolic parameters and oocyte quality, relations between embryo quality and endometrial status will be studied in repeat breeders in comparison to fertile cows. Possibilities of flow cytometry and triple fluorescent staining in the studies of capacitational changes of spermatozoa will be clarified and the relation of these changes to fertility will be investigated. Dynamics of quantitative and qualitative semen characteristics in young bulls of Estonian dairy breeds in the period of sexual maturation will be studied as well as heritability of some functional sperm parameters. Two PhD students participate in the grant project, their dissertations are planned to be completed in 2005 and 2006. The results of our studies are expected to clarify the reasons of repeat breeding in dairy cows and to find optimal combinations of laboratory tests for evaluation and prediction of bulls' fertility. |
| project group | ||||
|---|---|---|---|---|
| no | name | institution | position | |
| 1. | Triin Hallap | Estonian Agricultural University | PhD student | |
| 2. | Ülle Jaakma | EAU Faculty of Veterinary Science | professor 0.5 senior scientist 0.5 | |
| 3. | Jevgeni Kurõkin | Estonian Agricultural University | senior scienist | |
| 4. | Peeter Padrik | Estonian Agricultural University | Head of the production unit, member of the board | |