Newsletter – 2014 – March
It’s shaping up to be an exciting year for the Dairy Cattle Reproduction Council and its membership. We’re planning a number of changes in 2014, adding a number of new ways for you to participate in the organization and its valuable information and resources.
We’re working to incorporate several new features for members including new materials in the “members-only” section of our website, new sections in our bi-monthly e-newsletter and much more. Be sure to check out the new featured member section in this newsletter to learn more about how others are incorporating takeaways from DCRC into their operation and business. Other additions to the newsletter include this monthly message from the DCRC president, as well as new reproduction research, industry insights and a guest column that discusses important reproductive topics.
DCRC hosted its first webinar of the year on January 30. It featured Dr. Ricardo Chebel’s presentation about transition cow grouping strategies. Watch here in case you missed the original broadcast. Additional webinars are scheduled for April, June and September.
Also, don’t forget to mark your calendar for the 2014 Annual DCRC meeting in Salt Lake City, Utah, November 13 – 14. Program agenda details will be available soon, so stay tuned!
DCRC will host three upcoming webinars on the dates, times and topics below:
March 27th: Roles of Animal Health on Reproduction of Dairy Cows, by Dr. Jose Santos, sponsored by Merck Animal Health. Click here to preregister.
June 12th: Progeny Testing and Genomics: Where are we and where are we going? By Chuck Stattler
Sept 11th: Raising Heifers for Reproductive Success, Costs and Benefits to the Producer by Darin Mann, sponsored by Cargill.
If you missed the January webinar with Dr. Ricardo Chebel on Transition Grouping Strategies, view it on the DCRC YouTube Channel, along with other previous webinars.
Nominations Due April 15 for 2014 Reproduction Awards
The Dairy Cattle Reproduction Council (DCRC) has announced the 2014 Reproduction Awards program, which recognizes outstanding dairy operations for reproductive efficiency and well-implemented management procedures. Nominations are now being accepted for the 2014 program.
Dairy operations must be nominated by professionals who serve the dairy industry, such as veterinarians, genetic and pharmaceutical company representatives, DHIA field personnel or Extension specialists.
Judges will review applications and select the top herds, who will be asked to provide additional information about their operation. This information will help the judges select Platinum, Gold, Silver and Honorable Mention winners. Award recipients will be honored at the 2014 DCRC Annual Meeting in Salt Lake City on November 13 – 14, 2014.
Nominate a herd here: /awards/nominate-a-herd.aspx
Save the Date for the 2014 Annual Meeting
Mark your calendars for the 2014 DCRC Annual Meeting. It will be held November 13 – 14 in Salt Lake City. More details will follow shortly. Keep up-to-date on the DCRC website: /meetings.aspx.
Exploring the Link Between Fertility and Energy Balance
A study published in the February 2014 Journal of Dairy Science explored the relationship between postpartum energy status and fertility.
In it, German researchers used regression models to assess the effect of genetic merit for energy status on different traits and on subsequent reproductive performance of 824 high-producing dairy cows.
The results found that cows with a high genetic merit for energy balance had a significantly earlier resumption of ovarian activity after calving. The researchers conclude that an energy balance (indicator) trait should be included in future breeding programs to reduce the currently prolonged anovulatory intervals after parturition.
Is Genetic Variation Responsible for Susceptibility to Uterine Disease?
Since a number of environmental factors influence uterine health, it’s not easy to see what impact, if any, genetics have on this important key to reproductive success and cow fertility. Recent research at Texas A&M University published in the September 2013 Journal of Theriogenology offers some insight into the issue.
The primary objective of this study was to test for the associations between bovine single-nucleotide polymorphisms (SNPs) and insertion-deletion mutations occurring in seven bovine genes that are known to recognize bacterial ligands and the most significant uterine diseases in dairy cows, including metritis, clinical endometritis and cytologic endometritis.
The results show that several confounding variables—including parity, dystocia and ketosis before 17 days in milk—had more significance than genetics on uterine health.
Therefore, the researchers concluded that these data suggest that some of the examined SNPs may potentially elicit relatively small effects on uterine health in Holstein dairy cows and that some confounding variables are actually more predictive for the incidence of disease than any genetic markers evaluated.
Using Bovine Somatotropin to Enhance Fertility
Recombinant bovine somatotropin (bST) is most often associated with increased milk production by dairy cows. But recently, a team of researchers set out to evaluate the effects of administering either one or two low doses of slow-release bST on hormone concentrations, embryo development and fertility in dairy cows. The results were published in the January 2014 Biology of Reproduction journal.
The study followed 1,483 cows that were blocked by parity and assigned randomly to receive a single placebo injection at insemination (control), a single injection with 325 milligrams of bST (half the dosage of the commercially available product) at insemination (S-bST), or two injections with 325 milligrams of bST administered on days 0 and 14 (T-bST).
Results show that cows that received T-bST had an earlier rise in the pregnancy-specific protein B in plasma, increased embryo size and enhanced fertility. Cows that received S-bST did not show improvements in embryo development and fertility.
In conclusion, the researchers say that supplementation with two low doses of bST enhanced embryo development, reduced embryonic losses and improved fertility in dairy cows.
Improving Health and Immunity through Genetic Selection
Dr. Kent Weigel, Dairy Science Professor, University of Wisconsin – Madison
Dairy producers and geneticists have been looking for ways to link health parameters and genetics for years. We’ve tracked sire families over time and over many, many herds, and have often seen what we believed to be correlations.
But you have to be careful when interpreting these data. That’s because nearly every farm records health events and disease incidence differently. And some don’t track it at all. Furthermore, privacy and proprietary data concerns have limited access to information collected on a regional or national scale.
As a result, progress in making the connection between health and genetics via conventional data gathering methods has been slow.
When the bovine genome was sequenced, we learned a great deal more about individual genes. And the development of genomics means that we have more data to help determine a host of new information about dairy cows, including ties between health and genetics.
These data enable researchers and genetics organizations to cut through the variation caused by inaccurate data collection and provide a clearer picture of genetic variation and an individual animal’s susceptibility to disease.
For instance, research1 conducted last year in the United Kingdom found that a number of significant correlations exist between immune traits and other recorded traits including:
- CD4+:CD8+ T lymphocyte ratio and subclinical mastitis
- % CD8+ lymphocytes and fertility
- % CD335+ natural killer cells and lameness episodes
- Serum haptoglobin levels and clinical mastitis.
Importantly, the researchers say, these traits were not associated with reduced productivity and, in the case of cellular immune traits, were highly repeatable. Plus, these immune traits displayed significant between-animal variation—which has been a significant obstacle—suggesting that they may be altered by genetic selection.
In addition, research at the University of Guelph has focused on the heritability of immune response, which has been pegged at 25%. This means that 25% of the differences between animals for immune response can be attributed to genetics.
While this information is indeed helpful, especially in the case of infectious diseases, keep in mind that not all health issues are infectious. Many of the health challenges facing dairy cows during the all-important transition period, for example, are metabolic in nature and may occur in the absence of infection.
Going forward, producers and researchers stand to learn more about the genetic and health tie as more data from automated recording systems—activity and/or rumination monitoring—become available. These systems inherently take much of the recording variation out of the data, giving a more consistent view of disease incidence. These more accurate data have the potential to be integrated into future sire analyses.
Ultimately, we are probably not looking at a single measure, but a collection of data points that will give dairy producers and their management teams a more complete picture of how health and genetics go hand-in-hand, leading to more healthy and productive cows.
Meanwhile, continue to monitor sire evaluations for productive life, daughter fertility, calving ease, somatic cell count and other key health parameters.
1 Banos G, Wall E, Coffey M, Bagnall A, Gillespie S, Russell G C, McNeilly TN. Identification of Immune Traits Correlated with Dairy Cow Health, Reproduction and Productivity Available at: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0065766 Accessed February 24, 2014.
Featured Charter Sponsor
Select Sires has invested considerable resources into sexed semen since the commercial launch of the product nine years ago. The process of separating X- and Y-bearing sperm and creating the commercial product occurs at Sexing Technologies’ laboratories, which contract these services to Select Sires and all other studs offering a sex-sorted product. Sexing Technologies and Select Sires have collaborated on several research projects to test the fertility of this product under field conditions using Selects’ Program for Fertility Advancement (PFA) research herds. Compilation of U.S. dairy farm records indicated that sexed semen results in a conception rate that is approximately 80% of that obtained with conventional semen when used in virgin heifers (DeJarnette et al., 2009). Controlled field trials have indicated this reduction in conception rate is only modestly improved by increasing the number of sperm per straw (DeJarnette, 2010; DeJarnette et. al. 2011).
Sexing Technologies recently introduced several changes to the sex-sorting procedure to mitigate sperm damage, and again partnered with Select Sires to utilize PFA cooperator herds and evaluate the effect of these changes on field fertility. Ejaculates from each of eight Holstein bulls were divided equally and one half submitted to old sex-sorting procedures (control) and the other half to the new procedure. Forty-one herds from across the continental United States participated in this study resulting in 3,384 and 3,546 inseminations of virgin heifers for control and the new sex-sorting procedures, respectively. The new procedure resulted in a greater conception rate compared to the old procedure (46% vs. 41%, respectively; P < 0.001).
Results of this field trial indicate that enhancements to the sex-sorting procedure translated into improved field fertility, which is a step in the right direction towards conventional semen fertility. A conventional semen control was not included in this study; therefore, comparison of this new sexed product to conventional semen is not possible in the confines of this study. Similar field trials reported differences in conception rates between sexed and conventional semen of 41% and 58% (DeJarnette et. al. 2011) or 44% and 61% (DeJarnette, 2010), respectively. It is likely that sperm of some bulls are more sensitive to the sex-sorting procedure compared to other bulls. This trend is often noticed in these large field trials that utilize several bulls. Future research will likely attempt to reduce variation in fertility among bulls between sexed and conventional semen by identifying and improving parts of the sex-sorting procedure that contribute to this variation.
DeJarnette, J. M., M. A. Leach, R. L. Nebel, C. E. Marshall, C. R. McCleary, and J. F. Moreno. 2011. Effects of sex-sorting and sperm dosage on conception rates of Holstein heifers: is comparable fertility of sex-sorted and conventional semen plausible? J. Dairy Sci. 94: 3477-3483.
DeJarnette, J. M., C. R. McCleary, M. A. Leach, J. F. Moreno, R. L. Nebel, and C. E. Marshall. 2010. Effects of 2.1 and 3.5×10(6) sex-sorted sperm dosages on conception rates of Holstein cows and heifers. J. Dairy Sci. 93: 4079-4085.
DeJarnette, J. M., R. L. Nebel, and C. E. Marshall. 2009. Evaluating the success of sex-sorted semen in US dairy herds from on farm records. Theriogenology 71: 49-58.
Box Canyon Dairy Wendell, Idaho
Member since 2007
In each issue of the DCRC e-newsletter we will feature a current member who will share what they’ve learned from DCRC and the value they have seen in being a member.
Box Canyon Dairy is a third-generation family dairy in Wendell, Idaho. We operate on six locations in an 8-mile radius. The dairy milks 9,500 cows and our major focus areas are reproduction, milk quality, production, cow health/comfort, and food and employee safety. I am in a general manager role on the operation and help oversee 120 employees. I work closely with the owners to strategically plan their future vision and goals for the business, while managing day-to-day activities on the dairy with a key group of department managers.
Dairy Beginnings My dairy experience began as a nutritionist in Idaho and central California. I worked in dairy nutrition for eight years, then moved into a consulting role for Pfizer Animal Health (Zoetis) as a dairy production specialist and strategic account manager for five years. I joined DCRC early in my career as a way to more easily sort through the latest reproductive research. I feel dairy reproduction is a key factor in the success or failure of a dairy operation. The economics associated with reproduction can be staggering—both positively and negatively. The value of reduced days in milk, increased efficiencies and increased profitability are critical for our success.
DCRC Lessons Learned Two major things I have learned and implemented from DCRC meetings and newsletters are
- How to sort through all of the different synchronization options for timed breeding and resynchronization
- 100% compliance is the key to a successful reproduction program
If I cannot confidently implement a specific reproductive program, we will not try it, even if we know research says there would be improvement. For example, it took us nine months to move from Cosynch to Ovsynch® because we had to change feeding times, milking times and breeding times, so that we could attain 100% compliance and keep standing times as short as possible.
Crystal Ball One of the largest reproductive challenges facing the dairy industry today, in my opinion, is the ability of technicians to accurately detect animals in heat on larger dairies due to time constraints. I am also concerned about the word “hormone” from a consumer perspective. I fear the potential loss of synchronization programs if we do not find ways to properly share with consumers the need for and benefits, safety and use of these key reproductive management tools.