Progress 10/01/09 to 09/30/12
Outputs
OUTPUTS: Findings of this study have been incorporated into lectures in dairy cattle reproduction to veterinary professional students. A visiting lecture was delivered at Cambridge University, UK, during May 2011. Findings have also been disseminated at extension meetings in Florida, by a former student. Work was included in the graduate work of Dr. S.H. Cheong and incorporated into his PhD defense seminar at Cornell University, and at seminars given at the University of Illinois. Results of this project have been included in presentations to veterinarians in Argentina (2010), Italy (2010), Uruguay (2010), Brazil (2010) and Canada (2010) by Dr. Gilbert. Results of this research were incorporated into presentations to veterinarians registered for PhD degrees in reproduction at a course given jointly by the University of Tartu and the Estonian University of Life Sciences in May, 2010; 22 veterinarians from Scandinavia and Eastern Europe attended. Results were incorporated into presentations for veterinarians in China 2010, 2011 and 2012. PARTICIPANTS: Dr. R.O. Gilbert: PI Dr. W.R. Butler: Co-PI Trainees: Dr. S.H. Cheong (PhD) Dr. O. Balogh (PhD) Dr. K.N. Galvao Collaborating institutions: University of Florida St. Istvan University, Hungary. TARGET AUDIENCES: Academic veterinarians and animal scientists. Practicing veterinarians and animal scientists involved in the dairy industry. Veterinary professional students. Dairy producers. Dairy geneticists and animal breeding organizations. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The major findings of this project are as follows: 1. Cows ovulating before 21 days postpartum have superior reproductive performance to cows ovulating for the first time between 21 and 49 days postpartum, which, in turn, have better reproductive performance than those whose first ovulation occurs later than 49 days postpartum. 2. Cows ovulating earlier in the postpartum period are less likely to suffer from endometritis. 3. The detrimental effects of late ovulation and endometritis on reproductive performance are independent, and additive. 4. Cows failing to ovulate the first postpartum dominant follicle have lower dry matter intake starting at least 30 days prepartum, have more severe negative energy balance, and greater insulin resistance than cows ovulating the first dominant follicle. 5. Although cows ovulating the first postpartum dominant follicle have higher circulating concentrations of anti-Muellerian hormone (AMH; a measure of antral follicular count, or ovarian reserve) than non-ovulating cows, this effect is weak, and the high antral follicle count and early postpartum ovulation seem to be independent characteristics. 6. Preliminary results of a Genome-wide Association Study indicate that most significant hits so far are on chromosome 15 (SAAL1 - serum amyloid A like-1) and chromosome 4(HIBADH -- 3-hydroxyisobutyrate dehydrogenase; TAX1BP1 - tax-1 binding protein-1). Both genes play a role in signaling cascades related to inflammation. 7. In other results we have established a role for the GH-IGF-1 axis. These results were made possible by the activities of the personnel involved in this project. These results provide justification for enrollment of a greater number of cows into a genome-wide association study, with a high likelihood of discovering genetic markers to aid selection for fertility, and identification of genes that will enhance our understanding of fertility of dairy cows.
Publications
- Balogh O, Kovacs K, Kulcar M, Gaspardy A, Febel H, Zsolnai A, Fesus L, Delavaud C, Chilliard Y, Gilbert RO, Huszenicza Gy. Interrelationship of growth hormone ALUI polymorphism and hyperketonemia with plasma hormones and metabolites in the beginning of lactation in dairy cows. Livestock Science. 2009; 123: 180-186.
- Galvao KN, Butler WR, Brittin SB, Frajblat M, Guard CL, Gilbert RO. Effect of early postpartum ovulation on fertility in dairy cows. Reproduction in Domestic Animals. 2010 45, e207-e211 (2010)
- Galvao KN, Pighetti GM, Cheong SH, Nydam DV, Gilbert RO. Association between CXCR1 polymorphism and disease incidence, reproductive performance and milk production in Holstein cows. Journal of Dairy Science. 2011; 94: 2083-2091
- Gilbert RO. The effects of endometritis on the establishment of pregnancy in cattle. Reproduction, Fertility and Development. 2012; 24: 252-257. doi: 10.1071/RD11915; PMID: 22394966
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Progress 10/01/09 to 09/30/10
Outputs
OUTPUTS: This being the first year of the project, much of the dissemination of information was limited to our preliminary data and findings upon which the application was based although some new information was discovered and disseminated. Information obtained to date in this project has been shared in a variety of ways. These include incorporation of current findings in lectures to veterinary students taking an advanced dairy cattle reproduction course. Material was also included in lectures to veterinarians and veterinary students participating in the Summer Dairy Institute at Cornell in 2010. In addition, presentations were made to graduate students at several universities worldwide, including: University of Saskatchewan, College of Veterinary Medicine, March 2010; State University of Sao Paulo, Brazil, College of Veterinary Medicine, 2010; University of the Republic of Uruguay (Universidad de la Republica), College of Veterinary Medicine, April, 2010; University of Tartu and Estonian University of Life Sciences, Estonia, May 23 - 28, 2010; and the Faculty of Veterinary Science, Universidad Nacional del Centro, Tandil, Buenos Aires, Argentina, July 2010. Some data were also presented at a meeting of Veterinarians in dairy practice in Italy: SIVAR (Societa Italiana Veterinari per Animali da Reddito) Congress, Cremona Italy, May 6-8, 2010. Most of these audiences consisted of veterinarians or veterinary students. In many cases, proceedings were published, often in local languages, further facilitating dissemination of the information. The data and concepts of this study were discussed at the annual technical meeting of the National Association of Animal Breeders (NAAB) in Milwaukee, Wisconsin in September 2010. This audience consists of management of bull studs from around North America as well as leading reproductive scientists. At this meeting, officials of the NAAB also agreed to share some bull genomic information to facilitate our study and prevent duplication. Discussion of the goals and activities of this project in Uruguay have led to inauguration of a new collaborative effort to advance progress in this field. The animals in Uruguay are mainly of US genetics, so the information obtained there will be applicable in the USA. PARTICIPANTS: Project Director: Dr. R.O. Gilbert Co-Investigator: Dr. W.R. Butler Dr. Marcela Bicalho: postdoctoral associate Graduate Students: Dr. Klibs Galvao: Completed PhD and now Assistant Professor, University of Florida. Dr. Soon Hon Cheong: Current PhD student, Cornell University Collaborators: Dr. Gina Pighetti, University of Tennessee Dr. Ana Meikle, University of Uruguay Dr. Daniel Cavestany, University of Uruguay TARGET AUDIENCES: During the reporting year, veterinary students and veterinarians were targeted in presentations at Cornell University, the University of Saskatchewan, the University of Sao Paulo, the University of Tandil, Argentina, the University of Uruguay, the University of Tartu and the Estonian University of Life Sciences, Estonia. A non-veterinary audience was targeted at the annual meeting of the National Association of Animal Breeders. A greater awareness of the importance of genetics in dairy cattle reproduction is likely to be multiplied in their interactions with their producer-clients. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
For several decades genetics have been overlooked as a potential contributor to steadily deteriorating reproductive performance in high producing dairy cows. Our interest in this subject and our preliminary findings, along with those of others, have rekindled interest in a genetic approach to enhanced reproductive performance. The result is that reproductive traits are now given more prominence in many national and international breeding / selection indices. Although we cannot claim to have brought this about, we do feel we have contributed to this movement. Investigation of specific candidate genes suspected to have an impact on dairy cow reproduction has had mixed results. We have been able to confirm a lack of effect of mutations in the CXCR2 gene, and the ALU1 gene. On the other hand, we have obtained very encouraging data related to GHR polymorphism. Although we will continue to investigate candidate genes in an effort to understand the relevant biology, we have turned our attention for now to genome-wide association studies in the hope of identifying areas of linkage disequilibrium, which in turn will lead to more promising candidate genes and processes. In collecting samples and characterizing performance (phenotype) of dairy cows for this project, we have reinforced the importance of the relationship between energy status, uterine health, and ovarian function. Genes common to these processes seem likely to provide selection markers and we will continue to investigate them.
Publications
- Galvao KN, Butler WR, Brittin SB, Frajblat M, Guard CL, Gilbert RO. 2010. Effect of early postpartum ovulation on fertility in dairy cows. Reproduction in Domestic Animals. 45, e207 -e211 (2010); doi: 10.1111/j.1439-0531.2009.01517.x ISSN 0936-676
- Balogh O, Kovacs K, Kulcar M, Gaspardy A, Febel H, Zsolnai A, Fesus L, Delavaud C, Chilliard Y, Gilbert RO, Huszenicza Gy. 2009. Interrelationship of growth hormone ALUI polymorphism and hyperketonemia with plasma hormones and metabolites in the beginning of lactation in dairy cows. Livestock Science. 123: 180-186.
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