Newsletter – 2016 – June
By Dr. Stephen LeBlanc
A central goal of DCRC is to develop and disseminate information in support of effective and sustainable reproductive management of dairy cattle.
Sustainability is a key tenet of a successful business or production system, but it’s also a word that risks becoming a cliché. The three pillars of sustainability of a system are economic, environmental and social considerations.
Often, the first spotlight in agriculture is on the environmental sphere: water and land use, greenhouse gas emissions and nutrient management. As stewards of the land, this is familiar ground for dairy producers. With less arable land but a growing population, the concept of and need for sustainable intensification of food production has traction.
There is good evidence that synchronization programs for timed-artificial insemination (A.I.) and automated activity monitoring technologies are effective and economically viable management tools for dairy herds. Recent research1 indicates that application of synchronization programs can not only be profitable, but can also contribute to lower greenhouse gas emissions per unit of milk produced.
As a scientific researcher, my inclination is make decisions based on data and evidence. However, we must keep our eye on maintenance of social license—the acceptability of our production practices to our customers.
Market researchers underline the fact that consumers’ decisions are based on many things but, broadly speaking, are values-based more than evidence-based.
It is frustrating that surveys of consumers’ preferences often do not present trade-offs or consequences of expressed preferences. It is difficult to take direction from sentiments that are not well-informed by science or practical realities, or seem to conflict with environmental or economic sustainability.
Nevertheless, we ignore these cues at our peril.
We should continue to develop and implement reproductive management techniques that are effective, efficient and economical, and that are environmentally and socially tenable.
We should not shrink from using tools that meet all of the pillars of sustainability, understanding that the need for transparency in our industry will only grow.
We are very pleased to have presented our first Spanish-language webinar on June 24. We hope this will broaden access to the information that DCRC provides to our members and potential members globally. Please share the webinar information with your Spanish-speaking colleagues. If you missed it, members can access this and all recent webinars on our website.
The program is available and registration is open on our website for our annual meeting November 10–11 in Columbus, Ohio. Start making your plans now to attend this outstanding learning opportunity.
We are pleased to announce that our 2017 meeting will be held in Reno, Nevada. Your suggestions can help shape the program. Tell us what you want to learn more about.
Get every benefit from DCRC and let your colleagues know, too. Follow us on Twitter @DCRCouncil and like us on Facebook.
1. Archer SC, Hudson CD, Green MJ. Use of Stochastic Simulation to Evaluate the Reduction in Methane Emissions and Improvement in Reproductive Efficiency from Routine Hormonal Interventions in Dairy Herds. PLOS ONE 2015;10(6):e0127846.
Improving Feed Efficiency through Genetics
Dairy cattle feed efficiency has more than doubled over the past century, thanks to genetic improvement, nutrition advancement and better management. Researchers at Cornell University theorize the next leap in increasing feed efficiency will depend on identifying the most efficient cows and capitalizing on their genetic makeup that favors increased productivity rather than body maintenance. The study was published in the June issue of the Journal of Dairy Science.
Cows that convert feed gross energy to net energy more efficiently or have lower maintenance requirements than expected based on body weight use less feed than expected and thus have negative residual feed intake (RFI). Cows with low RFI likely digest and metabolize nutrients more efficiently and should have overall greater efficiency and profitability if they are also healthy, fertile and produce at a high multiple of maintenance.
The researchers say genomic technologies will help to identify these animals for selection programs. In addition, perhaps new computer-driven technologies, combined with genomics, will enable dairies to optimize management for each individual cow within a herd, or to optimize animal selection to match management environments.
Increase Embryo Production
To improve embryo production efficiency, researchers in Japan recently compared the outcomes of single GnRH injections 48 hours before each of three cycles of ovum pickup (weeks 2, 4 and 6) with three cycles of unstimulated ovum pickup (weeks 1, 3 and 5) in 35 Holstein cows during six weeks of early lactation (40 – 80 days postpartum). The results were published online in the Journal of Theriogenology on May 7, 2016.
Their findings showed:
- Significantly more oocytes stained positively with brilliant cresyl blue after GnRH treatment compared with the control cycles.
- After in vitro fertilization, embryos in the treatment cycles had improved development during each developmental stage compared with the controls.
- There was no significant difference in pregnancy rate of the recipient cows after embryo transfer whether the embryos came from the GnRH-treated cycles or not.
The researchers concluded that GnRH-stimulated ovum pickups improved the efficiency of embryo production in Holstein cows during early lactation.
Data Drive Insemination Success
Researchers in The Netherlands recently set out to develop a method to predict the likelihood of successful first insemination. To do so, they used data readily available at the time a farmer makes breeding decisions. The results were published online by the Journal of Dairy Science on May 25, 2016.
The following variables were used: parity, days in milk, days to peak production, production level relative to herd mates, milk yield, breed of the cow, insemination season and calving season, log of the ratio of fat-to-protein content and body condition score at insemination. The study found that the variables that contributed most to the model (and insemination success) were:
- Random farm effect
- Relative production factor
- Milk yield at insemination.
They concluded that insemination success depends on physiological conditions of the cow, which can be derived indirectly by routinely recorded production and reproduction data. Of course, the model cannot be used to distinguish cows that conceive from cows that do not. However, the model validation indicates that routinely collected farm data and test-day milk yield records have value for the prognosis of insemination success in dairy cows.
The Role of Inflammation in Transition Cows
By Dr. Barry Bradford, Associate Professor of Dairy Nutrition, Kansas State University
It’s common for transition cows to experience some level of inflammation. In fact, some level of inflammatory response in the cow’s reproductive system is necessary for normal functioning, especially during the pre- and postpartum periods.
But unusually high levels of inflammation in the weeks following calving are problematic because they are linked to poor health, productivity and fertility.
Extended periods of inflammation mean that the cow’s immune system is on high alert for long periods of time.
Why Does Inflammation Happen?
During infections, such as mastitis or metritis, immune cells in the body recognize invading pathogens and become activated.
The activation of these defense mechanisms requires cross-talk between several types of immune cells, and one component of this response is inflammation.
While many of the key signals promote local inflammation and increased blood flow to the infected tissue, a group of molecules called inflammatory cytokines play a significant role in stimulating systemic inflammatory responses, including increased body temperature, increased heart rate and decreased feed intake.
Cytokines activate production of acute phase proteins, which are primarily produced in the liver and participate in the acute-phase response to infection. These proteins generally occur in very low levels in the bloodstream, except during periods of systemic inflammation.
There is also an acute phase response in postpartum dairy cows, even in those that are apparently healthy. Researchers are exploring the contribution of calving in this process, in addition to the role of infections or endotoxins. Whatever the explanation, the prevalence of postpartum inflammation raises important questions about its implications for early lactating cows.
One critical role of inflammatory pathways in the transition cow is to promote labor and expulsion of the placenta. As with many reproductive processes, signaling molecules known as prostaglandins are critical in this process.
The same inflammatory pathways that activate immune cells can also stimulate prostaglandin synthesis. This is a critical process, because prostaglandin E2 synthesis in the fetal membranes is thought to help dilate the cervix and induce contractions.
In addition, even though excessive inflammation apparently slows uterine involution, some level of inflammation for a short window of time is probably essential for normal involution. Finally, although it is not well documented at this time, it is suggested that local inflammatory signals may help to regulate ovarian function.
Although most transition dairy cows apparently have a period of inflammation, the extent of inflammation varies greatly among cows.
Research1 has shown that cows in the highest quartile of inflammation produced less milk than those in the lowest quartile throughout the first month of lactation. The difference was 20 percent on day 28 of lactation.
Other findings2 suggest that stronger inflammatory responses during the first week of lactation are associated with decreased whole-lactation milk yield.
In short, abnormally high markers of inflammation are associated with poor production, health and fertility outcomes.
Should you Treat Postpartum Inflammation?
Research outcomes are mixed regarding this question.
- Milk Production Responses. A variety of researchers have used nonsteroidal anti-inflammatory drugs (NSAIDs) to treat postpartum inflammation. Some studies have shown increases in peak milk yield with aspirin treatments. Other studies in a variety of countries haven’t shown significant impacts of postpartum anti-inflammatory treatment on milk yield, and it remains to be seen whether a treatment can be found that is consistently effective. It’s believed, however, that impacts on long-term milk yield likely require treatment early after calving, but not before the placenta is shed.
- Health Impacts. Several NSAIDs have been used effectively in treating mastitis. It’s been shown that an NSAID had limited ability to suppress inflammation, but partially alleviated the decrease in ruminal contractions during induced mastitis in early-lactation cows, which could help prevent a subsequent displaced abomasum. It’s also been shown that incorporating a different NSAID in the treatment of mastitis subsequently reduced somatic cell count and decreased the number of cows culled from the herd. More research is necessary to determine whether blanket treatment of postpartum cows can really decrease this type of culling risk.
- Reproductive Responses. Links between inflammation, reproductive tract infections and infertility have motivated numerous researchers to evaluate impacts of anti-inflammatory treatments on reproductive outcomes. In general, these studies have shown little promise for decreasing the time to pregnancy after calving.
In addition to NSAID treatments, diets with higher levels of omega-3 fatty acids (protected in part from ruminal biohydrogenation) can be used to mildly decrease inflammatory status of postpartum cows.
A recent study3 demonstrated that supplementing either omega-3 or omega-6 fatty acids during early lactation increased peak progesterone concentrations during the estrous cycle, indicating that essential fatty acid deficiency may be a separate issue worth considering.
The Bottom Line
Unfortunately, health and productivity responses to anti-inflammatory treatment have been inconsistent, despite fairly consistent evidence that cows with heightened inflammation during immediate days after calving produce less milk and suffer from more disease.
Ongoing research hopefully will bring additional clarity about the benefits and potential risks of several postpartum anti-inflammatory strategies. Scientists are exploring possible treatments to manage negative physiological and economic impacts of extreme inflammatory responses.
1 Bertoni G, Trevisi E, Han X, Bionaz M. Effects of inflammatory conditions on liver activity in puerperium period and consequences for performance in dairy cows. J Dairy Sci 2008;91:3300-3310.
2 Huzzey JM, Mann S, Nydam DV, Grant RJ, Overton TR. Associations of peripartum markers of stress and inflammation with milk yield and reproductive performance in Holstein dairy cows. Prev Vet Med 2015;120:291-297.
3 Dirandeh E., Towhidi A, Pirsaraei ZA, Hashemi FA, Ganjkhanlou M, Zeinoaldini S, Roodbari AR, Saberifar T, Petit HV. Plasma concentrations of PGFM and uterine and ovarian responses in early lactation dairy cows fed omega-3 and omega-6 fatty acids. Theriogenology 2013;80:131-137.
Kitchener, Ontario, Canada
Member since 2008
I am the owner of Haas Nutrition, a family business, and I work directly with dairy farm clients. Haas Nutrition is an independent dairy nutrition and management consulting business with its own lab for feed, urine, blood and milk analysis, which helps us collect and further evaluate data for our clients. We provide data analytical services, economical evaluation of milk production, as well as set up monitoring systems and benchmarks for dairy operations.
I started my professional career as veterinarian, and divided my time between my clinic and our family dairy farm of approximately 500 cows. For the past 15 years I have worked as consultant for dairy farms in Ontario, Canada and the European Union.
Emphasis on Reproduction
I do not think a dairy farm can be profitable without a successful reproductive program. Efficient reproduction results in a herd structure (average days in milk, amount of first lactation cows, increased longevity or reduced culling, etc.) which allows for more efficient and more profitable milk production.
We have seen improvement in this area in the last four to five years and now we can say that we are able to achieve excellent reproduction parameters combined with high milk production. Improved fresh cow health and more precise synchronization protocols are big part of this success.
I consider reproduction, along with nutrition, udder and hoof health, as the four major building blocks for profitable dairy operation. These are all connected and influence each other. Many times is difficult to evaluate one without considering the impact of the others. All of these building blocks are impacted by the farm workforce’s ability to be consistent in everyday tasks and farm management’s ability to hire and train their employees.
Several recent DCRC communications and events have helped make adjustments in monitoring protocols on my clients’ farms, including a number of presentations from the 2015 Annual Meeting. These include:
- An update on fertility programs from Dr. Paul Fricke.
- An update on ketosis management from Dr. LeBlanc
- The impact of inflammation on reproduction from Dr. Bradford.
In my mind DCRC creates a bridge between science and the field. It brings everything under one roof. You have people who focus on research as well as professionals and farmers who are the ones who interpret and utilize the results of the research on dairy farms. DCRC’s annual meetings actually represent a great opportunity for some direct interaction between these two sides.
Reproduction Challenges to Overcome
Current synchronization programs are great tools to improve reproduction parameters on dairy farms, but I believe in the future we will have to better utilize and integrate new technologies to see if they are able to replace some of current programs with even better levels of efficiency. For example, a goal could be not only to achieve a 30 percent or higher pregnancy rate, but also to see how efficiently we can achieve it. Labor efficiency is a very important factor in this context.
Dairy farms around the world are under significant pressure due to low milk prices and shortage of labor. This trend will, in my mind, continue in the future, so it is up to us to implement new technologies that are economically sound and labor efficient.
- DCRC Webinar, Estratégias para mejorar el desempeño reproductivo en lecherias de alta producción” (Strategies to improve reproduction performance in high producing dairy herds) Friday, June 24, 11 a.m. (Central Time)
- Society for the Study of Reproduction 49th Annual Meeting, July 16 – 20, 2016, San Diego, California
- ADSA – ASAS Joint Annual Meeting (JAM), July, 19 – 23, Salt Lake City, Utah
- Mid-South Ruminant Nutrition Conference, August 17 – 18, Dallas, Texas
- DCRC Webinar, Improving Facilities to Optimize Cow Comfort, August 26, 1 p.m. (Central Time)
- American Association of Bovine Practitioners 49th Annual Conference, September 15 – 17, Charlotte, North Carolina.
- Minnesota Nutrition Conference, September 21 – 22, Prior Lake, Minnesota.
- World Dairy Expo, October 4 – 8, Madison, Wisconsin
- DCRC Webinar, Assessing Reproductive Efficiency, October 28, 1 p.m. (Central Time)
- DCRC Annual Meeting, November 10 – 11, Columbus, Ohio
- DCRC Webinar, 10 Years of Sexed Semen, December 16, 1 p.m. (Central Time)