Ask any dairy farmer, anywhere in the world, to describe their breeding goals and irrespective of the breed of cattle, the answers will be very similar. The nuances of their breeding strategy and choices differ marginally, determined by the local market and the production conditions. But high on every farmer’s wish list is a cow that produces effortlessly and converts feed efficiently into milk.
Numerous breeding values have been developed in recent years to facilitate a targeted breeding strategy that accommodates a range of traits. CRV clearly summarises all these breeding values in two practical indexes: CRV Health and CRV Efficiency. Using these indexes results in a healthy and efficient herd – to make every dairy farmer’s ultimate dream a reality.
CRV Health helps you breed a problem-free, healthy herd. This breeding index ranks the health traits of bulls in order of favourability compared with the average scores of the bull population. A bull who scores +6% CRV Health can be expected to produce daughters with 3% fewer problems with udder health, claw health, ketosis and fertility, for example. But the CRV Health index also incorporates traits such as the maternal calving process, calving ease and calf survival rate.
Selecting bulls based on CRV Efficiency will give you highly productive cows that convert feed efficiently into milk and have a long life with high lifetime production. Daughters bred by a bull with +6% CRV Efficiency will produce on average 3% more milk from their feed intake over their lifetimes. This implies additional lifetime production of more than 2000 kilos of milk. When calculating the CRV Efficiency index, breeding values for persistency, late maturity, calving interval and age at first calving are also included, in addition to the values for production and longevity.
The proven value in practice of breeding based on CRV Health and CRV Efficiency is substantiated by studies of over 100,000 cows from more than 900 Dutch and Flemish dairy farms. The (genomic) breeding values for CRV Health and CRV Efficiency are known for all of these cows, as well as their actual performance in the working herd.
Among other aspects, this research compared the 25% highest scoring cows for CRV Health with the 25% lowest scoring cows in the herd. The first group scored an average index of +4.2%, the second group an average of -2.3%.
The research revealed striking differences between the groups. Table 1 shows the performance in the first to third lactation. Cows with a high score for CRV Health were found to have a somatic cell count that averaged 55,000 cells per 100 millilitres lower than cows with a low score. They were also less sensitive to ketosis and claw and hoof disorders such as interdigital dermatitis and mortellaro. Cows with high breeding values for CRV Health also had clearly higher fertility. On average, they needed 0.2 inseminations fewer to become pregnant and had a calving interval that was 23 days shorter.
Table 1 – Comparison of the actual performances in the first to the third lactation on working farms of the 25% highest and the 25% lowest scoring cows for CRV Health.
|Bottom 25% CRV Health||Top 25%
|CRV Health Index||-2,3||+4,2|
|Somatic cell count (cells/ml x 1000)||161||107|
|% Subklinische mastitis||43,0||27,0|
|% Interdigital Dermatitis||15,0||9,0|
|% Ketosis (only 3rd lactation)e (alleen 3e lactatie)||12,0||7,0|
|% Live calves (first calving)||82,0||93,0|
|Number of inseminations per animal||2,2||1,9|
|Days calving interval||408||385|
Lifetime production more than 13,000 kilos higher
The same study also confirmed the merits of the CRV Efficiency index. The same group of more than 100,000 cows from 900 farms was also categorised based on the scores for CRV Efficiency. For this index the best 25% scored on average +9.8% with the poorest 25% scoring -2.4%. Once again, the differences in performance were significant. These figures are shown in table 2. For example, the highest scoring animals produced on average nearly 11,000 kilos of milk, 463 kilos of fat and 383 kilos of protein in the third lactation in 305 days. That adds up to a good 1000 kilos of milk, 37 kilos of fat and 32 kilos of protein more than the lowest scoring group of animals.
Table 2- Comparison of the actual performances in the third lactation on working farms of the 25% highest and the 25% lowest scoring cows for CRV Efficiency.
|Bottom 25% CRV Efficiency||Top 25% CRV Efficiency|
|CRV Efficiency index||-2,5||+9,8|
|Kg milk 305 days (3rd lactation)||9.940||10.981|
|kg fat + protein 305 days (3rd lactation)||777||846|
Another study among more than 22,000 animals also examined the performance of culled cows. The results of this study are shown in table 3. Here too, remarkable differences were noted between the 25% highest scoring (with an average score of +4.8%) and the 25% lowest scoring (with an average score of -4.4%) cows for CRV Efficiency. The highest scoring cows were not only more productive, they also had longevity of 274 days more. This resulted in a difference in lifetime production of more than 13,000 kilos of milk and more than 1,000 kilos of fat and protein.
Table 3- Comparison of the lifetime production of culled cows on working farms of the 25% highest and the 25% lowest scoring cows for CRV E0fficiency.
|Bottom 25% CRV Efficiency||Top 25% CRV Efficiency|
|CRV Efficiency index||-4,4||+4,8|
|Age at culling (days)||2.028||2.302|
|Kg milk lifetime production||29.048||42.134|
|Kg fat + protein lifetime production||2.277||3.282|
|Kg milk per day||26,4||31,1|
Healthy cows are efficient cows
Finally, the study examined the correlation between CRV Health and CRV Efficiency, to investigate whether breeding aimed at efficiently producing cows is at the expense of health. This was not the case. Quite the contrary in fact, the 25% highest scoring cows for CRV Efficiency also scored high for CRV Health. And this also proved true the other way around. Cows with the highest scores for CRV Health also scored high for CRV Efficiency. This result is actually perfectly logical, as healthy cows produce more milk with greater ease and live longer. And cows can only produce milk efficiently if they are healthy.
The balance between health and efficiency is what makes CRV’s breeding programme so unique. A healthy, trouble-free herd that efficiently converts feed into milk and guarantees high lifetime production is precisely what dairy farmers all over the world are looking for. It is the key to sustainable milk production and a better life for cows and farmers. The CRV Health and CRV Efficiency indexes put that key in your hands.