NEW MILK PROTEIN TESTS - Coming soon

[zephyrhillsusan]

Our future herd sire is homozygous A2 as is our cow who is about to calve. I already have her tail hair at UCD, so it will be easy to add the tests. The bull was done before we bought him, of course, but getting tail hairs sent off for these tests was on my list. You've prompted me to push it higher up, Patti. Since we only have two other females, I might as well do them even though they're hetero for A2, especially since I like making cheese. Since we'll be breeding them to the A2 bull, it will be interesting to know what they've got to contribute. I don't blame you for not doing everyone, Hans!

[kansasdexters]

Joel,

It has been confirmed in several published scientific research articles that Kappa Casein "B" variant is more desirable than "A" variant since it is linked with higher casein, total protein, and fat content in the milk, and higher cheese yielding capacity, as well as improved coagulation based on rennet clotting time and curd firmness.

The "B" variant of Kappa Casein and Beta Lactoglobulin is recognized as superior for milk quality (higher protein and fat) in European cattle breeds.

From my perspective, the cost of doing these two additional tests ($25 per test) is well worth the effort. This information aids in efficiently and reliably selecting from each year's production of calves, which ones have the most desirable functional traits to carry forward within our herd. The cost of keeping a female for two or three (or more) years before realizing that she does not possess the desired functional traits, is much greater than the cost of these genetic tests.

It makes sense to me that a cow that naturally produces milk with higher protein and fat, is a more efficient cow in terms of nourishing a calf. I'm currently interested in comparing these Kappa Casein and Beta Lactoglobulin genotypes with the data I've already accumulated on weaning weights for the cows in our herd. I suspect that the cows which consistently produce offspring with higher weaning weights are also going to be the cows with "B" variant Kappa Casein and "B" variant Beta Lactoglobulin. If this is the case, then it becomes a valuable selection tool for choosing replacement females and bulls as registered breeding stock.

Patti

[legendrockranch]

Hi Patti, I received the results from the one cow I had tested. Basically she was tested because I am planning on selling her and just out of my own curiosity.
She was already tested for A2, and is A2/A2, the Kappa Casein and Lactoglobulin were both A/B.
Quite honestly I don't know if I'll be doing anymore testing unless it's on my bulls. So what were the results on the cows you had tested?

Barb


From the VGL website:

Beta Casein (A2) is an important gene for milk production traits. The VGL test identifies the 2 most common variants: A1 and A2. The A2 variant has been shown to have a positive association with milk yield and protein content. The A2/A2 genotype is also considered to have positive effects on human health.

Kappa Casein is an important gene for protein yield and percentage in milk. The VGL test identifies the 2 most common variants A and B. The A variant and AA genotype are associated with higher milk production. The B variant and BB genotype are associated with increased milk protein and casein content, and better cheese yield. Relative to protein content and cheese production, BB is the most favorable genotype, AB is intermediate and AA is the least favorable.

Beta Lactoglobulin is the major whey protein gene. The VGL test identifies the 2 most common variants A and B. The A variant is associated with increased milk yield and whey protein content. The B variant is associated with increased casein and fat content and is favorable for cheese production.

[outofthebox]

Apr 9, 2014 14:00:58 GMT -5 kansasdexters said:

From my perspective, the cost of doing these two additional tests ($25 per test) is well worth the effort. This information aids in efficiently and reliably selecting from each year's production of calves, which ones have the most desirable functional traits to carry forward within our herd. The cost of keeping a female for two or three (or more) years before realizing that she does not possess the desired functional traits, is much greater than the cost of these genetic tests.

It makes sense to me that a cow that naturally produces milk with higher protein and fat, is a more efficient cow in terms of nourishing a calf. I'm currently interested in comparing these Kappa Casein and Beta Lactoglobulin genotypes with the data I've already accumulated on weaning weights for the cows in our herd. I suspect that the cows which consistently produce offspring with higher weaning weights are also going to be the cows with "B" variant Kappa Casein and "B" variant Beta Lactoglobulin. If this is the case, then it becomes a valuable selection tool for choosing replacement females and bulls as registered breeding stock.

Patti

Patti that makes a bunch of sense. Would you mind letting us know how those cows producing the higher weaning weights, tested?

[ssrdex]

Hi Patti
What you say makes complete sense from your perspective. I agree that it would be very interesting to know the results and to be able to compare them with the animals that produce the calves that have the higher weaning weights. I think I'm understanding you to say that one of the tools you use now to determine who stays or goes within your herd (weaning weights), which takes 2-3 years (2-3 weanings), will be replaced by these tests. So it's more than just a cheese thing. I really hope you are able to compile some numbers from your testing and record keeping. It would be so helpful for me to be able to see the differences in weights in relation to the tested cows, and how big the differences in weights are. Do the 2 cows that tested homo for all 3 "preferred" traits produce calves that consistently outperform the calves produced by the 12 that didn't? I guess that would be the kind of info that would help me decide whether it's just a cheese thing or not. I'm all for better cheese ( like I could actually tell the difference), but the ones that maybe can't make the best cheese still make good beef. You've got 12 that do or you wouldn't have kept them. You actually answered my original question in that it doesn't sound as though it's debatable as to what it takes to make the best cheese. So if that's a desired functional trait, needed to make the best cheese, one should test. I probably won't for now

[carragheendexters]

Hi Joel,

I think these traits are not so much for better cheese as such, but for a better yield of cheese per litre (or for you guys per gallon) of milk. That is, less milk required for more cheese.
It is my understanding that there are many factors that go into making a good cheese, the milk itself is only one of many. Sheri (Redridge) could probably comment on this, she has mentioned that she used to make cheese commercially with her dairy sheep. I think the skill of the cheesemaker also plays a huge part.

The ultimate breed of cow for cheese is apparently the Gloucester, which is quite rare now, though they are trying to increase the numbers. If anyone has ever eaten Double Gloucester cheese, they will know what I mean. It is an amazing hard cheese.

Regards Louise

[carragheendexters]

Hi Patti,

do you milk your cows and if you do, have you ever had the milk on the different cows tested for butterfat and protein? That is something that I would be interested in doing, and wondered if you had done this, and just how Dexters (and your different cows perhaps from different lines) compare in reality to what they are proposed to be able to do. I understand feed has a big impact and stage of lactation, but with you having a large herd, and a lot of cows in comparatively the same conditions, whether you could make comparisons?

regards Louise.

[kansasdexters]

Hi Louise,

We have milked several of our cows over the past few years, but we only do it on a daily basis for a few weeks early in their lactation. What we have observed is that some cows produce creamier milk than others do, and that there is significant individual variation in milk quality and quantity. Until now, we haven't had a simple test to identify which cows have the genetic potential to produce better milk quality (in terms of higher protein and fat levels).

By testing and identifying the individuals within our herd that have the genetic potential for better milk quality, we can now follow this group of females through their lactations and observe what benefits (if any) they may have to offer, compared with their herd mates that aren't homozygous for "B" variant Kappa Casein and "B" variant Beta Lactoglobulin.

These two new tests are simply additional tools in the selection toolbox, that we can now utilize when choosing and comparing the animals that will be used for breeding stock in the herd in the coming years. But there are many other factors that are also considered when choosing replacements to retain, or add to the herd. I view these new tests as a way of "fine-tuning", an additional means of differentiating between two similar animals.

We have just started to do these two tests in our herd, so I'm reluctant to draw many conclusions about our preliminary data at this point. It may take us awhile to determine what positive/negative correlations (if any) can be made.


Patti

[marion]

Great post Sheri! I agree with all you have said. Testing results are interesting and now affordable, but results should not be a reason for culling in Dexters...marion

[carragheendexters]

Thanks for your reply Sheri, that is good information. That is also what I am thinking. How far do we go with testing? And really what I would like to know how the genetic result correlates to reality.

Patti,
what I was thinking, is, it would be really interesting also if with all of those tested cows of yours, if they were the same stage of lactation, and they would be on the same feed, if you were to test butterfat (just for interest) and protein(to compare), and then compare that to the genetic results.
I think that would be a fun and informative thing to do.

Just for interest while on this topic, our neighbouring dairy farm started to include canola oil in the cows hard feed as a cheaper way to increase the calories in the cows diet. These cows over here are pastured (strip grazed) , milked 3 times a day when they are fed a grain mix(plus the canola oil added) while they are being milked, and also fed oaten hay at night when out on the night pasture for long stem fibre.

The protein levels dropped dramatically. They removed the canola oil and up went the protein levels. They couldn't explain it, as to why oil would drop protein levels. Nevertheless, they no longer feed oil.

regards Louise

[kansasdexters]

Louise,

We are thinking on the same track. Once we've identified the "group", we can study them intensively and learn from this.


Patti

[legendrockranch]

I personally declare you Patti the ADCAs resident statistician. Don't think I can officially do that, but if I could I would.

Barb

[ssrdex]

Apr 10, 2014 20:50:01 GMT -5 kansasdexters said:

Louise,

We are thinking on the same track. Once we've identified the "group", we can study them intensively and learn from this.


Patti

Patti
I know it's lazy and selfish of me but I sure hope you share! It would sure be appreciated. I talk a pretty good game now but will probably end up testing 2 of my homo A2 girls, just because I have to know. Looking for udder improvement first. I was going through the udder picture thread again and found a post of yours with a pic of Fina Muirstead. She is a lovely cow! Be interesting to see how she tests. Thanks for starting this thread. Very helpfull

[carragheendexters]

HI Patti,

I am looking forward to seeing what you find out, whether there is correlation or not. I suppose you don't really have to be consistantly milking the cows, I think all you would need to do is collect one milking period, wouldn't you? Would you need to collect a full 24hr period for testing, to get the average BF and protein for the 24hr period? I suppose you would also probably need to take into account the quantity of milk produced in that 24 period as well.

regards Louise

[kansasdexters]

Joel (ssrdex),

I just got the results from UC-Davis for Fina Muirstead. Fina has tested as homozygous for "B" variant Kappa Casein (B/B) and homozygous for "B" variant Beta Lactoglobulin (B/B). She also tested as heterozygous (A1/A2) for Beta Casein. She is our "weaning queen", consistently producing some of the highest weaning weights of any cow in our herd, since her very first calf. She has bred and calved every year since she was 2 years old. Fina is currently bred to Ace of Clove Brook and due with calf #9 the last week in April 2014. We will have to milk her for a couple of weeks when she freshens because she initially produces much more milk than what any single calf can take. Now I'm really looking forward to making cheese!!


Patti