Update on Proofs for Identical Twin Sires

Identical twins have identical genotypes. Pedigree-based genetic evaluation systems treat identical animals as full-sibs. This strategy was known to be suboptimal since it assumes that identical twins only have 50% of their genes in common, when in reality they have the exact same DNA and identical genotypes. For purposes of genetic evaluations, identical twins are expected to transmit the exact same genetic potential to their progeny. However, before genomics it was very difficult to prove that animals were genetically identical.

Since the identification of genetically identical animals was no longer an issue in the genomic era, Canadian Dairy Network (CDN) implemented an improved methodology in 2011 for handling proofs of identical males. As long as they were born after April 1, 2006, any pair of sires identified as having identical DNA via genotyping received the same genetic and genomic evaluations. Identical sires that were already progeny proven as of December 2010 continued to be evaluated as if they were regular full brothers.

Identical sires are treated as one individual animal by pooling their daughter information and calculating one domestic genetic evaluation. For example, if one sire in the pair has 300 daughters and its identical brother has 200 daughters, both sires receive the same genetic evaluation based on the combined group of 500 daughters. Pooling daughter information increases the reliability of their combined proof, compared to treating them as full-sibs in the past. The same proof for identical sires is sent to Interbull for the calculation of MACE evaluations on other country scales. Depending on how the other country, say United States for example, handles the MACE evaluation from Interbull in addition to any daughter data that either brother may have in that country, identical twins may receive differing official evaluations in other countries.

Case Study – Jordan and Jerrick

Identical twins Gillette Jordan and Gillette Jerrick were first progeny proven in August 2010 and ranked #1 and #7 LPI, respectively, including genomics. As a result, they were both returned to active service and widely used across the country, although Jordan was also previously used as a high-ranking genomic young bull. Since these bulls were born prior to April 1, 2006, their proofs remained separate. Now, both have thousands of daughters in lactation and type classified. Although over 80% of their daughter production data is still from first lactation, these bulls serve as an excellent example of how proofs of identical sires evolve over time (Figure 1).

When first proven in August 2010, the bulls had an LPI difference of 278 points based solely on their traditional proof without genomics. Over the following months and years, their traditional proofs fluctuated to some degree, both upwards and downwards, with the largest difference between them exceeding 400 LPI points. As of April 2013, the variation in the LPI scale was halved and the average LPI was increased by 1700 points so the differences between Jordan and Jerrick for LPI and its components were reduced as expected. Once both bulls reached over 1,700 production daughters in May 2014, their LPI difference before including genomics has consistently been less than 100 points.


Table 1 shows the difference in traditional proofs without genomics between the identical brothers as of December 2014. Jordan is currently 80 LPI points higher than Jerrick, mainly because his production proof still exceeds that of Jerrick’s, but by far less than it did during the first 6 months after these bulls were officially progeny proven. In terms of type traits, the brothers now only differ from each other by one point or less. Being that Health and Fertility traits are generally low heritability, more daughter data in first and subsequent lactations is required in order to reach high levels of reliability. For this reason, more difference between these bulls still exists for traits like Herd Life, Daughter Calving Ability, Temperament, Milking Speed and Mastitis Resistance. It is expected that as the reliability of their proofs for functional traits increases due to the accumulation of daughter information, their evaluations will continue to become more similar over time, as has been the case with Production and Conformation traits.

Table 1: Proof Differences as of December 2014: Jordan versus Jerrick



The current CDN policy for calculating proofs for genetically identical brothers still raises some controversy and questions from breeders. Based on the observed evolution of traditional proofs for Jordan and Jerrick, excluding genomics, there is no indication that the policy should be altered. Since both bulls have the same genotype, the inclusion of genomic information for official proofs reduces the observed differences in published evaluations even further. Based on their semen usage in Canada, Gillette Stanleycup and Gillette Windhammer, and possibly Gillette Wildthing and Gillette Willrock, are two other pairs of identical brothers that may serve as case studies in the future but it will take a few more years before they have thousands of daughters with sufficient data for first and subsequent lactations.

Authors: Lynsay Beavers, Industry Liaison Coordinator, CDN, Brian Van Doormaal, General Manager, CDN

Date: December 2014

Research investments in Organic Dairy projects announced

Research investments in Organic Dairy projects announced

Dairy farmers keep proudly innovating in dairy and investing in research that will help to improve practices on farms across the country. Recently, the Minister of Agriculture and Agri-Food Gerry Ritz announced an $8 million investment in the Organic Science Cluster (2013-2018), adding its investment to multiple industry partners’ contributions of $2.7 million. Dairy Farmers of Canada is a proud partner in this new Organic Cluster with an investment of $185,000 over five years in four projects.

The Organic Agriculture Centre of Canada at the University of Dalhousie will be administering the Cluster and oversee the implementation of 37 projects at 36 research institutions across Canada, including universities, Agriculture and Agri-Food Canada research stations, and others.

The dairy projects include :


  1. The development of sustainable alternative sources of bedding for dairy cows

Principal Investigator: Renée Bergeron, University of Guelph, Alfred Campus

 General objective: The study aims to investigate the use of switchgrass in two forms (deep-bedded chopped switchgrass or “switchgrass-lime” mattress) as sustainable, alternative bedding sources for dairy cows that also enhance cow welfare.


  1. Effect of exercise and stall modifications on cow comfort and performance in tie-stall farms

 Principal Investigator: Elsa Vasseur, University of Guelph, Alfred Campus


General objective: The present study aims to investigate, on 20 commercial tie-stall farms in Ontario and Quebec, how modifications of stall configuration may improve cow comfort and productivity, and whether cows provided with exercise will respond differently to stall improvements.


  1. Evaluating alternative therapies for the treatment of clinical mastitis on organic dairies

 Principal Investigators: David Francoz and Simon Dufour (Université de Montréal)

General objective: The general objective of the study is to identify, evaluate, and promulgate an alternative multi-pronged approach for the treatment of clinical mastitis (CM) in dairy cows. This research objective would directly answer the need for the development of an alternative approach for mastitis treatment on organic dairies, which was identified as an important priority at the 2012 Canadian Organic Science Conference.


4. Bioactive products from plants and control of internal and external parasites in large ruminants

Principal Investigator: Dr. Simon Lachance, University of Guelph – Campus d’Alfred

General objective: Develop new methods and products for the control of external and internal parasites with the use of natural repellents and bioactive components from plants.


The project summaries can be found at:  http://www.dal.ca/faculty/agriculture/oacc/en-home/organic-science-cluster/OSCII/theme-d.html


Heifer Genomics and Lactation Performance: Are They Related?

Over the past few years, we’ve seen many examples of the benefits of genomics on the sire
side. Quantifying the advantages of genomic selection on the female side has been slower,
primarily due to the cautious adoption of the technology at the herd level. Of the registered
Holstein heifers born in Canada in 2013, less than 5% were genotyped. On the other hand, CDN
projections show that uptake could increase to surpass the 18% mark by year 2020.

With genomic testing, producers have the opportunity to improve the genetic potential of their
herd and decrease costs. This can be done by capitalizing on the herd’s best genetics through
the use of sexed semen, flushing or IVF, or by selling the bottom end, breeding them with beef
semen or using them as recipients.

Genomic Tested Heifers and First Lactation Performance

Does a heifer’s first genomic prediction provide enough information about future performance to
allow confidence in selection and culling decisions at an early age? To answer this question, we
examined three Canadian commercial herds that extensively genotyped heifers born in 2011.
These animals were chosen since they have had the chance to complete their first lactation and
be type classified.

Graph 1 compares the first genomic evaluation for milk yield (GPA Milk) after being genotyped
as a heifer calf to the subsequent first lactation 305-day milk production. In total, the chart
includes 305 cows born in 2011 from the three herds. Average 305-day milk yield was highest
for Herd A, followed by Herd B, and was the lowest for Herd C. In general, within all three herds,
the higher the GPA Milk as a heifer calf, the higher the first lactation 305-day milk yield as a cow.
This clearly demonstrates the usefulness of genomic evaluations for heifers as a tool for
identifying the animals that will perform better in your herd as a cow.



Graph 1 also shows the equations for predicting the first lactation 305-day milk yield in kilograms
based on the genomic evaluation as a heifer. While the prediction is not perfect, on average 1 kg
increase in GPA Milk resulted in a first lactation milk yield gain of 1.2 to 1.5 kg, depending on the
herd. This exceeds the expectation of one kg milk yield per one kg of GPA Milk and presumably
results from appropriate management in each herd. The actual yield per kg GPA Milk can be
used to gauge whether the management level in a given herd is fully taking advantage of the
herd’s genetic potential. If the management level wasn’t taking full advantage of the herd’s
genetic potential, we’d expect the actual ratio of milk yield to GPA Milk to be less than one.

GPA LPI and First Lactation Performance

Is a higher genomic evaluation as a heifer calf associated with better first lactation performance?
To answer this question the three herds studied above were analyzed separately and their data
was subsequently combined to create Table 1. In total, 284 animals with a lactation and
classification in first lactation were included in the analysis. These animals were divided into
four groups of 71 cows based on their genomic evaluation for LPI as a heifer (GPA LPI). Table 1
compares the actual first lactation performance for production and type for the highest versus
the lowest 25% of these animals based on GPA LPI.

The heifers that ranked within the top 25% for GPA LPI in their herd performed better in first
lactation on nearly all accounts relative to the bottom quartile. As cows, the heifers that were in
the top quartile for GPA LPI produced more milk, fat and protein, and scored higher at first
classification for final score, mammary system and feet & legs than those in the bottom quartile.
Categorizing heifers into the top and bottom quartiles based on their genomic LPI resulted in no
significant difference in the average somatic cell count as cows in first lactation.

Table 1: Average first lactation performance for the top and bottom 25% for GPA LPI as a heifer



What Does This Tell Us?

These findings validate that heifer calf genomic evaluations can be an indicator of future
performance. In addition, they confirm that genotyping heifer calves at a young age can provide
producers with useful information for making selection and culling decisions. Lastly, these results
show that genomic LPI values for heifers can be used as primary selection criteria as they are
related to first lactation performance for both production and conformation traits.

Authors: Lynsay Beavers and Brian Van Doormaal
Date: May 2014

We are Dairy Farmers

We are Dairy Farmers

Presentation on Innovation and Competitiveness in the Agricultural Sector to the House of Commons Standing Committee on Agriculture & Agri-Food – May 5th, 2014




Run by farmers, for farmers, DFC is the voice of Canadian dairy farmers. DFC is the national lobby, policy and promotion organization representing Canada’s farmers living on more than 12,000 dairy farms. DFC strives to create stable conditions for the Canadian dairy industry, today and in the future. It works to maintain policies that foster the viability of Canadian dairy farmers and promote dairy products and their health benefits.




  • In 7/10 Canadian provinces, dairy is one of the top two agricultural sectors.
  • The sector’s GDP contribution has risen from $15.2B in 2009 to $16.2B in 2011, and thecontribution to Canadian employment market grew from 215,104 to 218,330 over the sametime period.
  • The Canadian dairy industry contributes annually more than $3 billion in local, provincial andfederal taxes.
  • An increasing proportion of farms are being operated solely by young operators (those 18 to 39 yearsof age), despite an aging farmer population.



The supply management system enables the Canadian dairy sector to effectively and efficiently manage the production of the perishable product with processor plant management to deliver Canadians with fresh, high quality, safe and nutritious dairy products.

Canada’s supply management dairy policy rests on three pillars: production management, predictable imports and farm pricing. The aim of the Canadian dairy supply management system is to balance supply and demand, as well as balance market power among the supply chain stakeholders.

Supply management is not the same today as it was 40 years ago. Farmers, processors and governments have worked together to improve and strengthen the system and increase the diversity of dairy products offered to Canadians.

Examples of Innovation in Dairy:

  • Making over 1000 cheeses, artisan cheese makers, who can be found all across Canada, provide significant economic benefits to their local communities.
  • Yogurt varieties have diversified and grown over the years; for instance Greek yogurt is increasing by 15% per year.


Farmers across Canada recognize that innovation drives efficiency gains in the industry and profitability. The stability offered by a strong supply management program has allowed dairy farmers to reinvest in their industry and on their farms through comprehensive research programs for example, where results deliver better management practices, better technology and better quality products for consumers.

The future sustainability and profitability of our industry is directly connected to the advancement and new breakthroughs in our genetics and genomics programs. Leadership is taken to set standards to produce the best milk in the world in a sustainable way and maintaining strong investments in primary production, human health and nutrition research.

Dairy farmers want to keep working with processors to innovate in dairy and welcome opportunities that increase demand for quality, nutritional Canadian dairy products to the benefit of all Canadians.



In March 2014, DFC welcomed the government’s announcement of close to $945,000 under the AgriMarketing program for traceability and to support DFC’s integrated on-farm assurance programs. This investment will help Dairy Farmers of Canada develop programs that confirm farmers’ commitment to continuous improvement. DFC’s proAction Initiative is dairy farmers’ commitment to excellence in dairy farming. Canadian dairy farmers want to collectively demonstrate responsible stewardship of their animals and the environment, sustainably producing high quality, safe and nutritious food for consumers.

The proAction Initiative is national framework that will bring various programs related to the best management practices on-farm under one umbrella. This new approach will allow the Canadian dairy industry to continue its leadership by assuring customers about farm practices. Canadian dairy farmers will collectively and proactively establish the terms and timelines for this Initiative. DFC’s investments in research have built a strong, science-based foundation for the progress and development of the proAction Initiative.

proAction will set best management practices in six key areas:

  1. Milk Quality
  2. Food Safety
  3. Livestock Traceability
  4. Animal Care
  5. Biosecurity
  6. Environment

Some innovation examples based on dairy research:

  • The research related to mastitis led to the development of a molecule which could serve as the basis for an antibiotic which would not develop resistance.
  • Dairy farmers’ carbon footprint is one of the lowest in the world while working under adverse climatic conditions.



A number of success stories are driving dairy farmers to innovate and make the safest and highest quality of milk for Canadians. A consistent body of work in research has been dedicated to delivering best practices to improve the health of dairy cows, prevent infections and disease, treat diseases like mastitis to reduce the use of antibiotics on farms, make farm environments more comfortable for cows and encourage the adoption of new technologies like the use of robotics to make farms more efficient.

DFC’s Canadian Quality Milk program is an on-farm food safety program designed to help farmers prevent, monitor and reduce food safety risks on their farms. It has achieved technical recognition by the Canadian Food Inspection Agency as adhering to HACCP principles and being scientifically sound. Farmers on the program implement best management practices on their farms and keep records to monitor critical areas of food safety. By 2015, all Canadian dairy farmers will be certified under the program.

How dairy farmers strive for the best:

    • The Canadian Dairy Information Centre indicated that in 2013, there were 407 robot farms in Canada or roughly 4.6 percent of the dairy barns across the country. This number has increased by almost 50% since last year!
    • In April 2014, CBC’s Steven and Chris visited Joe Loewith and sons’ dairy farm in Lyndon, ON. One of the hosts commented on the automatic “back scratcher”. He couldn’t believe that cows actually line up to use it and said it’s like they’re “going to a salon”. Purchasing a back scratchers makes smart business sense, keep cows clean, happy and healthy. This product has is being sold by agricultural equipment dealers across Canada.
    • Other examples of success stories includes the discovery, development and testing of a vaccine against infections caused by mastitis, an infection that costs Canadian dairy farmers $400 million in animal treatments and loss of milk.



Canada is renowned globally for being home to some of the best dairy animals in the world. This is a direct result of over 40 years of investments and work in dairy cattle genetics research and breeding programs. The results of which have been applied successfully at home and creating demand for our dairy cow genetics abroad.

The Canadian Dairy Network has led the industry in dairy genetics and genomics research by: providing genetic evaluations for all dairy cattle breeds in Canada; coordinating industry-funded research and development projects in the area of dairy cattle genetics and genomics; establishing national standards associated with supervised herd recording, publishable lactations and information used for genetic evaluations; and maintaining a national dairy database for the dairy cattle improvement industry in Canada.

Our reputation for superior genetics globally speaks for itself:

      • Canadian dairy genetic exports were valued at over $123 million in 2013, a $12 million increase from 2012, with exports to more than 100 countries. The industry only keeps growing; the first two months of 2014 saw almost $26 million in international trade.
      • In December 2013, Minister Ritz announced that Vietnam’s largest dairy wants to buy 10,000 Canadian dairy cattle. This could be worth up to an additional $20M for Canadian dairy farmers. An order of this magnitude demonstrates the confidence in the health status of our national herd and the high regard for Canadian dairy genetics.
      • Breeding and genetic improvements have transformed our animals over time. In 1970, Canadian cows produced on average 3,431 litres of milk. In 2012, this had increased to 8,331 litres, or 143%!



Dairy Farmers of Canada has been investing in dairy production, and human nutrition and health research for almost three decades. We are proud to have built and grown these investments over the years with our partners, including the federal government. Together, we are driving innovation in the Canadian dairy industry.

At the national level, DFC’s yearly investment in dairy production, and human nutrition and health research is $1.7 million. Of this, $750,000 is directed toward dairy farmers’ priorities to improve efficiency, on-farm sustainability, animal health and welfare, and dairy genetics. The contribution of research results has led to efficiency and productivity gains made on dairy farms.

Our research priorities in dairy are clear and built around three main themes: sustainable milk production, dairy genetics and genomics and human nutrition and health.

The goal of the Sustainable Milk Production theme is to increase the competitiveness and profitability of dairy farming in a sustainable way through the adoption of innovative practices and new knowledge. Examples of targeted activities touch on a number of areas like animal health, animal welfare, environment and food safety

The goal of the Dairy Genetics and Genomics theme is to help advance and establish national genetic evaluation systems for traits of importance affecting dairy cattle productivity, profitability and competitiveness. Examples include activities focused on genetic improvement for dairy cattle productivity and profitability with emphasis on health, mobility, and identifying milk properties to improve animal health.

The goal of the Human Nutrition and Health theme is to advance our understanding and competitiveness with respect to the role of dairy products. Examples include looking at the beneficial role of milk in cardiovascular health, metabolic health, healthy weight and body composition, including bone health and optimal nutrition and function.

Since 2010, DFC has partnered with the federal government under the Agri-Science Clusters Initiative for the creation of a Dairy Research Cluster. In the fall the government announced the renewal of its partnership with DFC to continue the Dairy Research Cluster program to 2018. By the end of 2018, investments in dairy innovation by government and industry will be $30 million dollars for 71 research projects executed in 23 academic institutions and research centres across the country, involving more than 200 scientists and training close to 300 students, our next generation of scientific innovators.

Science and innovation requires critical infrastructure – an assured long term investment that animals used for the purpose of innovating through research can be housed and milked in modern facilities, and land used to plant and test new forages and crop varieties to better feed our animals in a sustainable way.

DFC recognizes and appreciates the investments made by the federal government, along with industry’s investments, in state of the art dairy research facilities like the Dairy and Swine Research and Development Centre in Lennoxville, Quebec, the construction of the new dairy research facility at the University of Saskatchewan and the agreement between AAFC and UBC to renew the land use and facilities at the Pacific Agri-Food Research Centre in Agassiz, BC. Ontario dairy farmers are proudly investing in the construction of new state-of-the art facility in Elora, Ontario with multiple partners from government, the processing sector and other businesses in the dairy value chain.

With investments in dairy research facilities comes research projects and demand for scientists, students and other research professionals. So not only are research investments contributing to the next generation of farmers, it is contributing to the next generation of scientists and technicians in a time where there is a large skills gap. These young professionals are being trained for jobs that currently exist within the agriculture sector. In 2010, the ag and agri-food sector directly provided 1 in 8 Canadian jobs.

Examples from the first dairy research cluster:

      • A tool was developed to enable dairy farmers to quickly identify bacteria that causes mastitis and selectively treat only those quarters that are infected.
      • Tools were developed to ensure that dairy animals are well cared for through an objective assessment process. A means to identify animals who need special attention was also included.



Canadian dairy farmers are committed to producing safe, nutritious food in an economically, socially and environmentally sustainable way. Our objectives are to reduce greenhouse gas emissions from dairy farms; ensure the efficient and sustainable management of natural resources like land, soil, water and biodiversity in a way that will minimize costs while maximizing profitability; and address the socio-economic aspects of sustainable development to promote the economic, human and societal benefits of sustainability in the dairy sector.

Environmental practices on all dairy farms, regardless of their size, are regulated by federal and provincials laws. Dairy farmers exceed regulations, implementing environmental farm plans to improve manure equipment and storage, to maximize the use of manure as a fertilizer for soil, to adopt modern technologies allowing them to maintain the temperature and ventilation of their barns while reducing their dependency on energy. Several farmers are also collaborating with Ducks Unlimited to preserve wetlands on their land.

These practices reduce the carbon footprint as well as save money and energy. DFC also invests in research to continue reducing the impact on the environment, improve sustainability as well as the viability of dairy farms.

Last year a DFC-commissioned study supported by its research investment partners at AAFC and the CDC showed that the carbon, water and land footprints for Canadian milk production are among the lowest in the world. See Appendix A, for an info graphic showcasing the results of this study. Dairy Farmers of Canada is leading the way to making the Canadian dairy farm sector even more sustainable.

Commitment to the environment:

      • Less than 1% of Canada’s water usage is used to produce milk.
      • About 2% of Canada’s agricultural land is used to produce milk.



Dairy farmers have shown their commitment to drive innovation in dairy and look forward to continued, strong partnerships with the federal government and dairy processors to keep: building capacity in our sector, and develop our research professionals and students invested and engaged in our industry and ensure the delivery of results to farmers for efficiency and profitability.

Dairy farmers have made important breakthroughs and progress through their investments in research. Sharing those results with farmers and industry stakeholders encourages the adoption of new knowledge, new practices and new technologies. For dairy farmers, the Cluster initiative and continued investments in infrastructure enable strategic collaboration with their partners – the government, the industry and some of the best scientists from across the country to achieve our shared goal: to keep driving innovation in dairy.



Preliminary Results in Dairy Research Cluster 2 – Update on Dairy Cattle Genetics and Genomics

Preliminary Results in Dairy Research Cluster 2 – Update on Dairy Cattle Genetics and Genomics

Dr. Filippo Miglior is Chief of Research & Strategic Development at Canadian Dairy Network (CDN), Adjunct Professor at the University of Guelph and principal investigator of two genetics projects under the Dairy Research Cluster (Hoof Health and Nutraceutical Value of Milk, see www.dairyresearch.ca for short summaries of the work). 

Dr. Miglior has delivered initial results from both projects, which are summarized below. 


Hoof Health 

Preliminary findings suggest there is sufficient genetic variation to allow for the genetic improvement of hoof health through direct selection. Standardized data collected by hoof trimmers can be used for genetic analysis.  

Initial work by Dr. Nuria Chapinal (Post-Doctoral at U. of British Columbia) found that digital dermatitis was the most frequent hoof lesion (present in 20% of the records) and primarily affected cows in their first lactation. Sole ulcers were the second most common lesion (8% of the records) and their frequency increased as cows aged. The heritability estimates for digital dermatitis and sole ulcer were 8% and 2%, respectively.

Additionally, a funding proposal by the Field Project Manager (Ms. Anne-Marie Christen) was prepared for the implementation of the hoof health data collection in Quebec. Ms. Christen has also prepared an inventory of past and current projects on hoof health across Canada and created a new networking group of professionals, researchers, hoof trimmers and veterinarians.

Nutraceutical Value of Milk

Initial results indicate that selection for milk fat globule and casein micelle size may be possible. The sizes of fat globules and casein micelles in milk have been associated with differences in the technological properties and composition of milk with a possible effect on human health. By decreasing the dimensions of the fat globules and by increasing the content of the milk membrane, milk production could be adapted to specific consumer targets and to the improvement of milk nutraceutical properties. 

A total of 1,330 milk samples from 249 dairy cows in 25 herds were analyzed by Dr. Milena Corredig’s lab (Professor, U. of Guelph). Ms. Allison Fleming (Ph.D. student, U. of Guelph) performed the genetic analysis. High heritabilities of 57% and 50% were found for volume weighted and surface area weighted milk fat globule size, respectively. The heritability of casein micelle size was 29%.

Additional Funding

We are happy to announce that the Ontario Genomics Institute (Toronto, ON) has approved funding to the DairyGen Council of CDN for $25,000 towards genotyping cows to add onto existing funding of the Dairy Research Cluster genetics projects. In order to successfully achieve significant and applicable results, the goal is to genotype at least 10,000 cows with the 50K SNP panel.  By pooling genotypes from various projects and by adding this investment from the Ontario Genomics Institute we expect to lower the cost of genotyping.

Is Sex-Biased Milk Production a Real Thing?

Tell a dairy farmer there’s an easy way to increase milk production by nearly 450 kg over the first two lactations, and you’ve got their attention! In a recent scientific paper (see reference below), researchers using DHI data in United States claimed just this. The authors hypothesized that milk production in first lactation is affected by the sex of the calf produced, but also by the sex of the fetus gestated during that lactation. They further predicted that the udder’s capacity to synthesize milk across all lactations is influenced by the sex of the first fetus, with females being advantageous. Canadian Dairy Network (CDN) performed a similar analysis using Canadian data to see if results were consistent.

CDN Analysis

Using Canadian data for lactations from cows that calved between 2001 and 2013, information was restricted to only individual births associated with lactations one to five where the sex of calf was recorded. Overall, 5.4 million lactations from 2.5 million cows were included in the analysis. Heifer and bull calves were represented in nearly equal ratios for calvings associated with each lactation.

Effect of Calf Sex on Subsequent Lactation Milk Production

As presented in Figure 1, 305-day milk yield was higher in each lactation following a calving that resulted in a heifer calf compared to a bull calf. Lactation yields following the birth of a heifer calf were 60-70 kg higher for the first two calvings and slightly more than 100 kg for later calvings. The higher production differences associated with later lactations are expected given the general increased production capability associated with older cows. Yields of fat and protein followed a similar pattern as for milk production, therefore keeping percentages unchanged.



Effect of Calf Sex on First and Second Lactation Production

A subset of data was used to examine the effects of calf sex combinations on first and second lactation milk yields. Since production is reduced following a difficult calving, the analysis was restricted to only include calvings that were reported as unassisted, unobserved or an easy pull.

This group of 210,099 cows was divided into four categories based on the various combinations of sex of calf at first and second lactation. Cows with two consecutive female calves were labelled as “FF” and those with two consecutive male calves were “MM”, which was used as the base group of cows for comparison. Other cows were grouped as “FM” or “MF” according to the sex of their first and second calves.

As shown in Figure 2, milk yield in first lactation was higher for cows that had given birth to a heifer calf and were then pregnant again in first lactation with another heifer. Cows that fit into this category produced 0.3% (24 kg) more milk in their first lactation (305 days) than cows that gave birth to a bull calf and were pregnant with another male. Any effect of carrying a heifer during the cow’s first pregnancy was essentially eliminated when the second pregnancy (i.e.: during first lactation) resulted in a male calf (FM-MM). Carrying a heifer calf during the first lactation pregnancy did show some increase in first lactation production but very small at 13 kg.



For 305-day milk yield in second lactation, the sex of the first pregnancy had no effect, as seen by comparing FF-MM versus MF-MM (1 kg difference) in Figure 3 as well as FM-MM versus MM (5 kg difference). Second lactation production was improved, however, by 0.6% (52-53 kg over 305 days) for cow’s that gave birth to a heifer to initiate that lactation compared to cow’s with a male calf at second calving.


For the first two lactations, the cumulative benefit of having two consecutive heifers compared to male calves (FF-MM in Figures 2 and 3) amounts to an increase of 76 kg (0.4%). This is much lower than the value reported in the US study, which claimed a two-lactation benefit of 2.7% and 445 kg. Authors in the US state that the marginal increase in production after gestating a heifer calf could be related to circulating hormones, which differ in male and female fetuses and in maternal circulation during pregnancy.

The Case for Sexed Semen

Sexed semen provides an array of benefits: more heifer replacements, easier calvings and the opportunity for increased genetic progress. In addition, the analysis by CDN shows that using sexed semen to produce more pregnancies with a heifer calf, instead of bull calves, can lead to an increase in milk production. However, it is important to note that this increase is very small at less than 0.5% across the first two lactations. There are many good reasons to use sexed semen, but increased production is so marginal, it can hardly qualify as one of them.

Authors: Lynsay Beavers and Brian Van Doormaal
Date: March 2014

Reference: Hinde K., Carpenter A.J., Clay J.S., Bradford B.J. (2014) Holsteins Favor Heifers,
Not Bulls: Biased Milk Production Programmed during Pregnancy as a Function
of Fetal Sex. PLoS ONE 9(2): e86169. doi:10.1371/journal.pone.0086169


Get Social. Get with the Herd. And Let’s Talk Dairy Research Shop!

Get Social. Get with the Herd.  And Let’s Talk Dairy Research Shop!

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By David Wiens,
DFC Board Member of the Cluster Research Committees

Welcome to our Dairy Research Blog. We’re pleased to offer this new blog to have a conversation with our dairy community (our herd!) on the research we finance in production, genetics and genomics, and human nutrition and health. It’s our place to talk Dairy Research Shop!


Unknown-1.jpegHere we’ll talk about the progress made from 23 new research activities launched on January 1st 2014. Most of the projects end in December 2017 and they’re all financed under this second Dairy Research Cluster funding partnership. (see the article entitle Driving Innovation in Dairy for more information). We’ll also post recent articles and extension information published thanks to the great work done by our science community in the first Cluster (48 projects completed from 2010-2013!). Our infographic on the situation of Canadian milk’s footprint is a great example.

We’ll feature some guest bloggers too so you can meet the scientists doing the research and the many students that support them. We’ll post pictures and videos of research results and extension articles we publish in your favourite magazines. Or, point out new posts made in our Dairy Research Portal website. It has a fresh new look that will give us more research information to chew on. While you’re connecting with us on our Blog, don’t forget to sign up and join the other members of our herd on Twitter and Facebook. Here too we’ll be talking Dairy Research Shop and sharing information that can help you on your farm.

Take a look around the site. Sign up to receive regular updates and join us, get social and get with the online herd!

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Driving Innovation in Dairy

Driving Innovation in Dairy

Driving Innovation in Dairy:  Industry and Government Reinvest in Canadian Dairy Research

Canadian dairy farmers will keep driving innovation in dairy with new investments of $18.8 million in a second Dairy Research Cluster program now in place for the next five years. On September 16, 2013 the Government of Canada announced that it would invest $12 million in the Dairy Research Cluster, partnering with Dairy Farmers of Canada, the Canadian Dairy Network and the Canadian Dairy Commission to fund new dairy research projects under the government’s AgriInnovation program.

Dairy Farmers of Canada will lead this second Dairy Research Cluster and invest $5.3 million in addition to the $12 million by Agriculture and Agri-Food Canada. The Canadian Dairy Network will invest $669,000 and the Canadian Dairy Commission $750,000, bringing the total to $18.8 million in funding to address the industry’s research priorities from 2013-2018.



There are a total of 23 research projects involving more than 100 scientists, from 15 institutions and 8 government research centres across the country. Some of the nations best dairy scientists  will train more than 65 graduate students and post-doctoral fellows over the next 5 years. The overall objective of the program is to promote the efficiency and sustainability of Canadian dairy farms, grow markets and supply high quality, safe and nutritious dairy products to Canadians.

The first Dairy Research Cluster program (2010-2013) led by Dairy Farmers of Canada and was launched in 2010. This second cluster builds on research priorities and projects carried over in part from the first Cluster.

What follows is a general overview of the research activities under each theme. The projects are slated to begin on January 1, 2014.

THEME 1:  Sustainable Milk Production

GOAL: To improve the competitiveness of the dairy sector and consumers’ perceptions of Canadian dairy products through the adoption of innovative practices and new knowledge that contribute to the economic sustainability of the sector and the strengthening of markets for dairy products.

RESEARCH PRIORITIES: Twelve projects will address the safety of milk as a sustainable source of nutrients through improved animal health and welfare; environmental and socio-economic sustainability of dairy farming; improved milk composition and nutrition using genomics.

EXPECTED OUTCOMES: Research activities under this theme aim to develop new management practices and strategies to improve the use nitrogen through more efficient production of protein by dairy cows; better use nitrogen from manure to fertilize crops; develop improved feeding practices to reduce GHG emissions from enteric fermentation; conserve water and find ways for its more efficient use; and create a self-assessment tool to help farmers manage GHG emissions from different farm practices.

Animal health and welfare will be addressed through a number of projects aimed to minimize the effects of mastitis and improve milk quality and safety; extend the longevity of dairy cattle by developing better strategies for lactation persistency, reproduction and dairy cattle and calf welfare practices; and create a database to collect dairy cattle health information to keep track of the effectiveness of dairy cattle health initiatives.

cluster-chart1_eng2.pngTHEME 2:  Human Nutrition and Health

GOALS: To better understand the link between dairy foods, nutrition, health and wellness in order to improve the health of Canadians and reduce health care costs; to contribute to the economic development of the dairy sector through increased consumption and the commercialization of new products and technologies.

RESEARCH PRIORITIES: Seven projects will include activities that focus on cardiovascular health, metabolic health such as type 2 diabetes, healthy weight and body composition including bone health and optimal nutrition and function.

EXPECTED OUTCOMES: Emerging scientific evidence shows a beneficial role for milk products in reducing the risk of conditions like obesity, cardiovascular diseases, type 2 diabetes and osteoporosis (all health burdens that add substantial costs to our health care system). More research will be done to better understand the role of milk products in these conditions including the role of regular fat milk products such as cheese, which is an important milk product in the diet of Canadians.

Health Canada is in the process of finalizing a Guidance Document on Health Claims related to food and satiety. The role of milk products on satiety and food intake is an emerging area of research and the role of food on satiety is a current topic of interest for the food industry in relation to health claims. Therefore, research in this area will help to provide the scientific substantiation in accordance with these guidelines.

The results of a recently commissioned systematic review by Dairy Farmers of Canada have identified important research gaps with respect to the role of milk and milk products on bone health. More specifically, there is a need for well-designed studies such as randomized controlled trials. These studies are important for advancing our understanding and in providing the scientific substantiation needed for health claims related to milk and milk products and bone health.

Furthermore, data from some of the research activities will be useful in the formulation of novel and functional foods and provide data within the Canadian context, which is particularly important for developing new health claims in Canada.

THEME 3: Dairy Genetics and Genomics

GOALS: Research activities in this area will help advance and establish national genetic evaluation systems for traits of importance affecting dairy cattle productivity, profitability and competitiveness.

RESEARCH PRIORITIES: Four projects will concentrate on genetics and genomics research that leads (a) genetic improvement for dairy cattle productivity and profitability with emphasis on health and mobility; (b) genetic improvement of milk properties affecting human health; (c) the effect of genetic improvement on GHG emissions; and (d) the development and application of genetic, genomic and epigenomic methods to achieve those objectives.

OUTCOMES: Canadian dairy cattle genetics is widely recognized globally for the outstanding balance of high production combined with the functional conformation required to sustain such productivity over multiple lactations.  These characteristics aim to maximize the possible revenue achievable from a dairy cow over her lifetime. The profitability of a dairy cow and a dairy herd is a function of both revenue and expenses so the activities of this research effort focus on reducing the costs of production, which therefore enhances the durability of the Canadian dairy cow and its competitiveness nationally and internationally.

Projects aim to capitalize on the opportunities and possibilities for higher genetic selection accuracies achievable through genomic evaluation models and the associated genetic selection strategies.

Canadian Dairy Research Portal

New project summaries are posted online at the Canadian Dairy Research Portal www.dairyresearch.ca. Canadian dairy producers and industry can access dairy research information and subscribe to our newsletter Dairy Research Update to keep informed of progress and developments.

Current Perspective on Crampiness in Holsteins

Current Perspective on Crampiness in Holsteins

Canadian Dairy Network (CDN) provides genetic evaluations for a multitude of traits that contribute to dairy farm profitability. In addition to the well-known production, type and functional traits, the type classification system also records a series of defective characteristics at the time each animal is appraised by a Holstein Canada classifier. One of these characteristics, namely “Crampy” within the Feet & Legs section, has received increased interest amongst breeders in recent years so it’s a great time to
report on the ongoing research in this area.

Defective Characteristics

The current type classification system in Canada provides classifiers the opportunity to record the occurrence of any one of 29 defective characteristics, which adjusts the animal’s classification scores accordingly. Ten of these defectives are associated with
the Mammary System while there are seven for each of Feet & Legs and Dairy Strength plus five more in the Rump section of the classification scorecard. When an animal is appraised, the classifier may “tick” the animal as displaying the defective characteristic at two degrees of severity: minor or major.

As CDN processes the classification data to estimate genetic evaluations for Conformation and the other 28 published traits, it also analyzes the data associated with each of the defective characteristics, including “Crampy”. On a sire by sire basis, the frequency of each defective is calculated based on their classified daughters. Ratings are assigned for each bull, which can been accessed on the CDN web site by clicking on the Type Evaluation Details page linked to the sire’s Genetic Evaluation Summary. Bulls with a significant frequency of a given defective characteristic, such as “Crampy”, among their classified daughters are identified with an asterisk (*) next to their negative (i.e.: undesirable) numerical rating.

Genetic Nature of Crampiness

A scientific analysis of defective characteristics reported by researchers at the University of Guelph in 2000 demonstrated a reasonable degree of genetic inheritance for some of the recorded defectives, which included “Crampy”. More recently, CDN conducted a pedigree analysis of progeny proven Holstein sires that had a higher than normal frequency of “Crampy” in their classified daughters. Table 1 lists the group of sires that have at least ten proven sons in Canada of which at least 30% of those sons have a negative rating for “Crampy” and 10% or more have a rating that is -2 or lower. Of the ten sires listed, some demonstrated the crampiness syndrome themselves and some had a higher than average frequency of “Crampy” noted in their classified daughters, but these observations are not true for all of them. Some sires in Table 1 could have a higher proportion of their proven sons rated poorly for “Crampy” depending on the maternal side of their sons’ pedigrees. While it is not clear cut that these sires all transmit the genes associated with crampiness, Table 1 provides strong evidence that there is a genetic component underlying this disease in dairy cattle.


Frequency of Crampiness

Figure 1 shows the frequency that “Crampy” was ticked during classifications carried out over the past twenty years. From 1994 to 2004, roughly 0.2% of classified Holsteins were found to be crampy and this incidence has slowly increased to approximately half of one percent (i.e.: 1 in 200) in 2013. While this increase is not cause for alarm, it has created more interest in “Crampiness”, also known as Spastic Syndrome, among breeders and research scientists. While there seems to be a general perception that a
single elite sire, namely Braedale Goldwyn, has been the underlying source of this trend, the fact remains that less than 1 percent of all his classified daughters have been identified as “Crampy”. There have been other bulls in the breed with incidence rates that approached 10% although most were ultimately not returned to active A.I. status as a proven sire.


In 2011, the DairyGen Council of CDN provided funding on behalf of industry partner organizations to a team of researchers at the universities of Guelph and Ottawa to conduct a 3-year project focusing on the Spastic Syndrome in dairy cattle. The main objectives of the project are to better understand the mode of genetic inheritance of this disease, which is normally considered neuromuscular in nature, and ideally to identify the associated genes. A key benefit to this research is the existing genotypes at CDN for thousands of progeny proven sires and cows, some with crampiness and others without any signs even beyond 8 or 10 years of age. Contrary to initial thoughts, this disease in dairy cattle is complex with possibly a variety of forms of expression and multiple controlling genes. The current project is scheduled to continue through 2014.


The type classification service provided by Holstein Canada for all dairy cattle breeds includes the recording of 29 defective characteristics, one of which is “Crampy”. Previous research and a recent analysis at CDN provide strong evidence of genetic inheritance associated with this neurological disease, which is often referred to as Spastic Syndrome among veterinarians. In association with each genetic evaluation release, CDN also calculates, and displays on its web site, individual bull ratings to reflect the observed incidence of each defective characteristic among their classified daughters. Negative ratings are associated with a higher than average frequency and an asterisk (*) is displayed for ratings that are significant within the breed. On behalf of
all industry partners, the DairyGen Council of CDN funded a 3-year research project to be completed by the end of 2014 that aims to clarify the mode of inheritance of crampiness in dairy cattle and possibly identify any causal genes.

Author: Brian Van Doormaal
Date: November 2013