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NHAES Education Session: Feed supplements to organic dairy cows.


Well, good morning everyone. I know everyone here, so it will be an intimate talk I guess. So I’ll be speaking kind of broadly on the topic in terms of feed supplements to organic dairy cows. You know, having conducted several studies at UNH the last three or four years, but I’ll be
basically speaking here today about the impact of flaxseed on, you know, animal production and greenhouse gas emissions. And again just bringing the talk here back when, you know, I talk about organic dairy cows of course most of the information here is applied to dairy cows in general particularly more like forage based systems so flaxseed is a, as you know, an oilseed that is rich in omega-3 fatty acids particularly, you know, alpha linolenic acid, which is known to be transferred to milk. Milk high in omega-3 fatty acids has some potential health benefits to humans, and also for the cows. So feeding flax seed also has been shown to increase other beneficial fatty acids like the conjugated linoleic fatty acids, also called, commonly, CLAs. In addition to just potential health benefits Flaxseed has also been linked to reduced methane emissions. Methane emissions, you have to bring it back, is not only better for the environment. Reduced methane emissions, in general, shows improved feed efficiency in lactating cows. So, just getting the idea here in terms of the talking a lot about fatty acids in milk, so that’s the general classes. Most of the milk fatty acids are saturated fatty acids, they’ll range from 55-80% of the total fat. 15-30% of the total fatty acids in milk are called monounsatuarated fatty acids, basically with one double bonds between carbons. We also have polyunsaturated fatty acids which is seen in a smaller proportion of the total milk fats. And its basically those are, the polyunsaturated fatty acids, are linked to improved human health. So, just going back here, the saturated fatty acids have no double bonds between the carbons. Straight structure, that’s why fats made of those fatty are basically solid at room temperature. Monounsaturate fatty acids have one double bond That’s why, you know, it gives it a “kink” and bends the molecule. Takes more space. That’s why it makes fats more liquid at room temperature. And polyunsaturated fats there are more than one double bond between the carbons That the CLAs, omega-3 and omega-6 fatty acids are examples of PUFA. of polyunsaturated fatty acids. Bringing back to the overall scope of the project funded by NEFA, they are again present in the extension initiative in the last we are in the third year now and with the overall idea here is to find ways to increase the grazing season, to extend the grazing season we looking at through you know, annuals, using perennial rye grass and this study has been conducted here and in New York, up to Pennsylvania so we also looking at flaxseed addition, but as you know when animals move from pasture to winter feeding, in general, there is a reduction in fatty acid composition, particularly the CLAs, so we expect by including flax we could give a higher concentration of fatty acids Those omega-3s and CLAs year round we also have the profitability aspect of this project that’s been conducted by UVM So it is kind of a multidisciplinary approach to improve fatty acids and extend the grazing season across the Northeast. showing basically again two studies we conduct two studies one we call kind of a dose level response we try to see what the best dose of flaxseed is in the ration so we increase from zero up to fifteen percent of the diet dry matter and experiment two was the grazing experiment, which we increase up to ten percent, which you’ll see why in a couple slides just the ration here, you can see basically replacing soybean meal as you can see here in corn meal with flax. So, flax going from zero to 15% of the diet dry matter and by doing that we replaced soybean and corn meal, because flax seed, as you’ll see in a moment, it is high in protein and fat. So, this is basically the composition of our ration, the TMR What I want to point out here is the crude fat, of course, as you increase flaxseed, which is a high energy seed, you increase the fat in the ration. from 3.8 to 7.4 and NFC, which is indicative of starch, is going down because you take corn out of the ration. You are replacing starch with fat in the rations, so know that, for those not familiar, that is the ground flaxseed which is full of fat which we can see here is 33 almost 34% of the dry matter feed is fat okay and also very high in protein, almost 22% is crude protein, as you can see there So, just getting some of the methodology for those of you who may not have been at UNH, so we use those individual gates to manage individual intake of the cows. You know, several simple procedures, blood sampling, tube the cows to get rumen samples. Those cows are organic. We basically cannot do surgeries on them using antibiotics, so we do the hard work here to do the samples through the tubing to study ruminant function. Animals are equipped with this device to collect methane so basically methane that is belched, we’ll capture in the cannisters and then we collect the sample and we have an idea of the methane concentrations, the methane emissions, in those cows So, some date here. Milk production as we increase the concentration of flax in the ration, we have this linear decline in milk production, ok. So there was statistical significance there. Losing about 2 pounds or so in milk as we increase flax and probably related to the negative impact of the oil on the rumen function. As you can see here, also a linear decline in dry matter intake. Dry matter intake in pounds/day in the y axis, you can also see this linear decline. So which brings us back to this situation that you know that if flax is a supplement that should be considered at higher levels or not. You can see maybe up to 10%, you lose some milk 15 percent is really putting things down from here to here you have a one pound loss in milk and which was overcome in terms of the milk fatty acid profile as I’ll show in a minute here. So, as milk production went down you can see that all the components also follow that so you see milk fat linearly decreasing as you increase flaxseed in the ration Save milk protein content, milk protein yeild, in the end, produced collective of a reduction intake when the cows have a production of this protein gram reduction intake so that basically brings MUN down Which is positive I’ll say Here is the CLAs I think that we’re interested in a lot as well, so you can see as you increase flax, you have an increase in The most important CLA, the most bioactive, is c9, t11 CLA and also total CLA went up you know, particularly when you move from the 10 to the 15 imagine that’s true because milk now is als rationed, is also increased at bioactive fats in milk, the most bioactive you can see here very clear another point that omega-3 and omega-6, so the omega-6 is going down, which is you want omega-3s are going up linearly with more flax in the ration, so the omega-6/omega-3 ration is more favorable in directions with 10-15% of flaxseed So, methane other thing we are looking at flax increase, methane emissions also decline so there are some trade offs here. Decrease in milk production and milk components, but also increase some of the beneficial fatty acids and reduce methane emissions. In industry, we need to look and see if there will be a premium for carbon, less carbon. Also, if it will be a premium for milk that is enriched with those beneficial fatty acids So, that’s kind of the first study in a kind of fast showing that we have here we then, based on that information, we also interested to see how is the year round use of flax, so we fed at the winter feeding and then during the grazing season and we picked up the 10% based on some of those results, so we choose a 10 percent dose of flax, which is appears to be the one that has positive impact on the fatty acid, but also in not reducing the milk drastically. So, that’s kind of the ration that we just finished last September, so I don’t have all the data diet are related have about 40% of pasture and at UNH we feed the TMR and the TMR was, you know, Baleage, some molasses, ground flax and some organic grain meal. Again, we are replacing starch with fat, roughly here. So, some of the procedures we used those ice , called ice cubes, basically who know what the cows do in terms of activity how long she kept laying down, walking. So, it counts steps and it monitors her movement at the farm we measure temperature every five minutes using temperature buttons in the tail. and also we look at those grazing behaviors. We want to see how those rations impact grazing behavior. and time the animal is ruminating, eating, and things like that. So, we do our usual sampling procedures. You know, botanical composition of pasture, pasture biomass pre- and post- grazing measurements of pasture intake so, interesting here, in this study I broke down by month, because we had the study across the grazing season. As you can see here from June to September. So general, you see there is no dietary fat, there is no difference between the zero and 10% we have a numerical reduction in milk production by about one pound less milk in cows receiving the 10% flax, but there is no statistical difference. In fact here, August is the month that cows seem to produce more milk Again, I don’t have all the data to see the pasture composition, but it appears to be the month that the cows produce more milk. The TMR intake also kinda followed that milk production I don’t have yet exact intake data, but TMR intake was a little bit lower in the flaxseed, particularly in the month of August and there was a dietary fat her, so the cows on flax they consumed less TMR. which, again, corroborates the data from the winter feeding trial. Again, the difference was really small, in terms of not even a pound in terms of TMR intake so milk fat content you see no difference across the season. You know, the average is based only 4.2. A little more in the flax, but no statistical difference. Milk fat yield follow and basically, you know, was little bit higher in the month of August The same for milk protein contents, no statistical difference between between the rations so it’s just basically saying there is no difference between flax and no flax Cows did not respond differently. In fact, some reason, again, I don’t have all the data set, have a higher concentration of milk protein in September. And the milk protein yeild, again, no difference between the two diets and the cows were producing more milk protein in August More milk production in that time period Again, no significant difference between rations in terms of milk protein yield. So we also measured methane using the GreenFeed System, which is basically an automated system that the cows visit the feed station and while she is consuming her pellets, we use alfalfa that is automatically drop every minute
for her she can stay there for five minutes there, but she is eating there are methane sensors that collect methane and CO2 all those animals need to get trained they know there is some feed there, so they go back Here is just another view of the system This a solar panel we can deploy on the pasture and every time the cows move, we can move the system with the cows so we can have a good number of these stations and you can see here that’s the methane, which is different you know, there is no significant statistical difference which is in contrast to the winter feeding trial, but you can see here that the number of visitation is over 4000 visitations in 120 days, so we kind of think it is a reliable technique in terms of number of points we can get, but there is no statistical difference in terms of methane emissions, but again, we are still in the preliminary analysis of the data set to get an idea of the production. Take home message here it’s clear that increasing flaxseed
interaction basically you have a negative impact of new production and new components however there was an increase in the milk fatty acid profile. It was a more favorable with the omega-3s and the CLAs And in general supplementing flax grazing season had no negative impact on milk yield and composition, but did not mitigate methane emissions at least in this first study that we did. With that we’ll open for questions

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