[Music] today I'll talk about sub productivity and at least the my perspective on nutritional aspects and characteristics of lactating sounds so the background for this presentation will be some how this genetic selection for for larger litters in in South so from the last 20 years we have had a steady increase in in in total on per cell which has been quite stable and around 0.3 piglets per liter per year so how does this affect the sour productivity yeah we see that when we have more piglets in a leader we also have increased litter weight at least slightly so it's the little weight only increases by approximately 500 grams for a piglet increased in litter size so this means that we also have a negative impact on birth weight actually yeah 30 grams for pig so we see in this going from from 12 to 14 piglets to a little size of around 25 we go from Irish piglet weight on 1.5 to almost 1.2 1.3 so it has a large impact so this is the background and I've divided it into three point of the lactation period so the initial part which is the firing also in the beginning of the face which is a colostrum production so they all have a bit in time but very differently in terms of after the function when the last part will be focusing on the production and well it will include characteristics and and try to answer if we have some nutritional means to have impact on these traits so let's start with the ferric processes it's the same story we have increasing a number of total born which is related to the fair integration yeah yes so so the firing duration increases by approximately 24 minutes for each picture that we know later so this means that the South spent a lot of time on this let's thing up to 14 hours and also there is a association between the fairing duration and the number of stillborn piglets so from this we cannot tell if we have more stillborn piglets caused by a longer fairing duration or we have a longer duration if we have a presence of stillbirth but I will anyway give some perspectives on how this could be related and energy for the cells might be a important factor in this aspect so around flowering South sourced at spend energy pricing up laying down on nest building they will use up to 14 hours to to give birth to these piglets and and how do we feed energy to these cells so this is just a figure showing that that the these cells spend a lot of energy on this process so this is a respiration rate of the cells in the normal condition and during lactation and we see in legislation they already start to breathe harder likely to to nest-building during flowering it's even higher and it's just a a good indicator I think that this is an energy requirement process so it's like putting a sow that has never been moving around on a bike to ask him to write to de France or something it's it's just to say I think it's it's it's an energy task and and how do we then feed these cells even with the barley and wheat based diets perfectly made 50% of the dry matter is coming from starch and it's rapidly digested taken up in lactate or glucose from a stomach and the small intestines M so how rapid is it then they study fat sounds 2 kilos of weed Impala based diet in the morning and only one time the day so 50% of this might approximately be stat so during the first 5 hour at least during the first hour we have the peak and we see a five-fold increase and then it starts to decrease so if we have a sow we feed a sow in the morning it starts firing 10 hours later it might be being already low in energy and then we ask them to do a tremendous task so a former colleague of mine tried to look into that how could how could we put it into two numbers so he took data from a previous experiment that we did with sows around patrician and he and he then correlated with the duration of firing so this is if we for example feed us our 8:00 in the morning it starts firing at 9:00 it's one hour between feeding and unset of firing and corresponding that to the fairing duration and he found that the longer time between the last feeding before I started firing and and the unset affarin was linked to a longer firing duration so the meal frequency might affect this this trait so if we feed them twice a day with 12 hour intervals we will have a maximum of 12 hours between the spirit so we're feeding the South more frequently we can reduce this so maybe six times today might be too much but let's say three times we already reduce [Music] the maximum length between the feeding and the start instead of firing yeah so this was the meal frequency but we all we saw before that this curve this is just an arbitrary curve of glucose uptake from feet so we have a peak the sow probably have enough energy start firing and finish rapidly but we might also instead of changing feeding frequency we could change feed intake the meal size so that might also have a positive impact in fact normal practice in in in Danish condition has been to lower feed intake inlet to station and that might not be I got a good idea in relation to the firing process but the OL on feed intake might also have an impact so another way so we could feed starch but another way it could be to feed fibers so the fermentation products of fibers would contribute to the to the south during a longer period actually it's been shown to be rather constant for for a long time from the period of time but the amounts are lower compared to glucose so if we plot it compared to the previous curve I've shown you so this is energy from glucose and this is energy from short chain fatty-acids either from south via the standard I'd a high amount of soluble fiber or high of mind of insoluble fibers so we see right after feeding it doesn't contribute a lot but already six to ten hours if you feed high amounts of fiber you can have a lot like a rather large contribution of energy for these sounds and and especially if you only feed yourselves one times a day it might be relevant and so we did a commercial productivity study in a commercial hurt and had two groups of South one fairly controlled diet in light of station and one fed fiber-rich diet they were all fed a similar amount of energy but they differ in the amount of starch so the result from this was that there was no impact on the total bone but actually the number of stillborn percentage was reduced from eight point seven to six point six we actually also did that did the study too we thought that we could impact pre winning mortality because we thought fiber had a and positive effect on colostrum yield but it didn't it only affected still burn stillborn piglets so that could be really related to the to the energy availability of these sounds but of course as as hell at all just before fiber fermentation products of butyrate has a lot of function show so it could also be related to other things for example the fire fibers have an effect on feces consistency feeding high amounts of fiber would give more soft faeces of reducing constipation high fiber in diets would also increase the water consumption but nevertheless a finished study showed that South that were more constipated also have it had a tension tendency to have had lower longer pharynx so to sum up this process we see that the last layer increases the fairing and and it likely also the increases the importance of energy so one way to deal with that could be to change the meal frequency equal intervals and and maybe during the night as bruno suggested it could be to increase feeling taking legislation or at least not decrease it so keep a high feed intake and I know this is currently in Westerly investigated in at all University right now so there will be some data on that later and also fiber may affect the energy availability and the firing process one way are the or another if we then go to colostrum production it is somehow the same study a story we have a large leaders but the association between the sow colostrum mule and the number of total born piglets is it's not linear so if we see the capacity of these litter sizes we see that it's almost linear but when we look at the what the cell produces in total we see that it might follow the intake capacity at the lower letter size but at the larger litter size it seems to be the sow that limits this crush on production so this means that the more piglets in the litter the lower amount of colostrum on average piglets is available so it decreases by by by 15 grams of piglet so during the last 20 to 20 years we had an increase in 6 piglets Polina so this means that almost a hundred grams less per piglets is available so that does impact the survivability of these piglets and to show the variability of the colostrum production I took this figure so we have here the colostrum intake either as an errors of a sow or the individual piglets which are the blue blue points and then we just have 60 random sounds and we see that this is a indicator of the South the red point so we see have a lot of variability within South but also a huge variability with the English each letter and we actually have quite a large proportion of the piglets not having a very high intake of colostrum so you have to be fast a fast piglet to get enough and what is enough French study was done some years ago dividing piglets into groups home on how much callosum they ingested and especially when you go under approximately 200 grams of of colostrum papac the previa mortality increases and this study was almost repeated again some years later but they also divided into the size of the birth weight so we had low low birth weight medium birth weight and high birth rate and we see this is a low colostrum entering is even more severe for for low birth weight piglets and and that's what we also is one of the consequences of of selecting for greater litter size so we have a greater litter size smaller piglets and the smaller amount of colostrum per piglet and this puts the its it puts more importance of this topic of improving colostrum production so what is actually the most important thing is it quality is it yield or what is it if we look at the individual pig as we saw on the figure for survival it's a hiker Ostrom intake but for the second point is that if we were born to sow producing last amount of colostrum the chance of being one of of having enough would also be greater and well as quick colostrum quality has not the same impact often also yield and protein protein content is negatively associated so from the point of view of the pig you should aim from high corrosive liquid intake but as we feed the sow we would like to increase the yield of the South to increase the chances of the individual picture to have a high color dimension so what are the risk factors as as I mentioned before quite a large proportion have a fallow intake let this is approximately 20% of the piglets and if we go back to this figure we see maybe 50% mortality of these piglets so if we have 20% and 50% mortality this is 10% of your piglets lying dying because of that also looking on Eretz south yield we see this cell have a low birth weight as we talked about before but also a low feed intake is a risk factor and a billion study was done some years ago on on the feed intake strategy comparing a low-end feed intake on 1.5 kilos per day compared to slightly more than four kilos per day and they that did not have an impact on fat but it did impact lactose concentration which was lower in the low feed intake group and it also affected the yield of colostrum per kilo of peak which was higher and if you had a high feed intake the total yield was higher and the litter gain which is a good indicator of colostrum yield was higher so if we reduce feed intake to 1.5 we also compromised colostrum yield I'm not saying we should feed four kills per day but based on what we saw on the firing process we should be at least not lowering our feed intake in late the station in addition to this some other approaches to supply energy for this house was done using a dietary fiber sources so in this study sounds were fed one of four experimental treatments during the de station period so these fiber sources were either sugar beet pulp pectin residue potato pulp or controlled wide diet low in dietary fiber but these were the fiber content of these diets were between 30 and 40 percent so it's quite a lot amount of fibers and it had an impact on the piglet gain during the first 24 hours of after patrician being highest for the beet pulp and the pectin retching you so we thought energy availability in later station would be the key for that so we we made a study feeding fibers during the last 10 days of gestation either from beet pulp or alfalfa slightly lower percentages and we had a control diet we did not find a significant effect on the piglet gain but we did find some small numerical effects a similar study was French study was was done also in the same period of time they used fiber mix instead of the pure fiber source or one ingredients but did not find out anything on Pickler King so the results on dietary fibers and kurosu ouma are not that clear so far so then we wanted to dig more into when is the colostrum produced and and how much is produced before patrician and after patrician the first step in this was looking into the literature finding these photos of lipid droplets being secreted into the liver all a lumen of the memory cells of the mammary tissue and that increases from day hundred and five two hundred and twelve indicating that we have some colostrum production at least at that point also looking on the serum IgG we see that the it decreases in late to Station indicated that is taken up by the memory glands whereas lactose in plasma is being indicated of the mammary glands starting to produce lactose and it's it Peaks first on that day of flowering so lactose might be a little bit later another approach we did was to take biopsies of the sows in legislation so to see when when does the gene expression change so we took a serial sequential mammary tissue samples and compare it to day minus fourteen as a reference so on day minus 10 that was not happening no changes compared to day minus 14 not much changes on day minus six as well but on day minus two is something started to happen more than 400 genes genes were upregulated compared to day minus 14 and 300 downregulated and this was even greater on day one and then we wanted to to get some quantitative numbers on the nutrients so we used multi Cathedral eyes someone in order to understand the dynamics of when is it the nutrients transferred and how much so we took sows they were washed and anesthetized and akathisia was placed in the hind lake in the artery to represent what entering the blood memory gland and to were placed in the second and the fourth memory gland and then they were exteriorized at the back of the cell so this was just to show how it looked like and this is a more schematic model of the of the of this house so we had the sampling catheter of the artery representing was entering and a sampling catheter of the membrane so the difference between artery and the vein should indicate what's happening in in the mammary glands then we used a blood flow market to quantify these numbers so in that way we could look what's on the on the blood side of the mammary gland what's how much do they take up use that as indicate what does this mammary glands require in terms of of nutrients we also measured picks and weights to estimate the colostrum yield and we took colostrum samples so we use that to estimate how much in quantitative did they secrete these cells so I'll start with latest ation this is unde 812 and gestation and this is the input so that what's taken up by the memory gland in moles of carbon either from glucose lactate triglycerides short chain fatty acids so the memory and took up approximately 20 moles of carbon from these nutrients I said was in legislation there was no colostrum secretion so we had an output this was co2 released back into the bloodstream and we also had a release of non-esterified fatty acids into the bloodstream so they could indicate mmm high metabolic rate of fat during this period and also we had a gap between input and output corresponding to a person widely 55 grams of fat per day so that could be used for retention of for colostrum or which just returns enough fat then we did the same in the first 24 hours from birth of the first piglet so the colostrum period again glucose lactate regular slight triglycerides and short chain fatty acid was taken up but now also NEFA were taken up by the mammary glands and in addition to the release of co2 into plasma we also have secretion of lactose and fat and the gap between input and output corresponding to a 120 35 grams of fat they might are written from from what's being retained in inlet of station but also what was interesting to see was that 50 percent of the carbon secreted during the first 24 hours was or was also taking up that at that point at that time so not not so much was synthesized preferring this indicates so to sum up on this chorus from production again last virus means that there's less available colostrum / piglet so the importance of colostrum for each pictures increases colostrum is highly important for survival and for later growth as well and if we restrict this house too much it will decrease colostrum yield so it may not be wise to decrease feed intake in like the station the results on dietary fiber are more unclear it may or may not improve a colostomy yield and we found out that the main part of the colostrum is synthesized after onset of patch evasion yeah I think so the last part is the milk production so is between they wanted a 28 in this in this sense again we have increase in life on piglets so it increases the demand for milk so I just on this figure I've plotted the litter gain on the different week in lactation from 150 liters and rank them by performance so the tempo scent lowest and the 10% highest and the rest in between so we see that from the high producing to the low producing sounds it's almost a double amount of litigate so it's quite a high variation but we we tend to feed the sounds the same way a lot of this variation is caused by a little size and winning so we see lost 10% weaned less pig less than the highest 10% so how do we find out what does this sound require with this last differences so we took the same approach with the Cathedral South studied the sound at peak lactation on day 17 and we wanted to study in this case that uptake of amino acids again using arterial blood as a reference and and the memory lane and the difference between those two as the indicator of what's going on in the memory gland so first I would like to present the material concentration of lysine and leucine and the memory extraction of these so if we start with loose lysine we see that this is time after feeding so before feeling we had a rather low concentration of lysine in arterial blood it increased almost threefold after feeding and decreased again so so this could indicate that it already indicates that the lysine was limiting in that diet how does the mammary gland respond to this change before feeding the extraction was very high so we see that almost 60% of this concentration was taken up by the cell so when the concentration increases the extraction decreases so the mammary gland takes with almost what is what it needs so the uptake is quite constant whereas the supply is more variable I also brought like leucine because it was stable across at the time after feeding and at a very high level so it would also be an interesting amino acid so then we quantified the uptake of essential amino acids and I didn't and we saw that lysine was limiting so we could relate the others to two lysine and well we could use that as a indicator what does a mammary gland require for milk production and if we compare that with the recommendation from the French system and the NRC and the de nies requirement recommendations we see it's it's almost the same slightly differ in 309 but it looks quite similar so we have the mammary gland it's producing it takes what it needs and and not more so the requirement by the mammary glands reflects what to a largest thing and what's in the milk so we cannot only look at the mammary gland we want to take a whole animal approach when you want to feed this house so milk output is to a large extent determined by their performance and important parameter in this is pig litter size so it's a it's a nit determinate the the performance then if we don't feed this out in enough to support this meth production it starts to mobilize but that might also be a limit and how much can the cell mobilize so in order to look at that idea I took ten recent studies focusing on sanitation and public rather recently and they had a aerosol as I said weeding on almost thirteen piglets Passau brains in between eleven point five and and thirteen point six so based on the content of lysine in the diet and the feed intake we could estimate the lysine in take based on litter size and picked that weight and mud composition we could estimate the output in milk of lysine and based on changes in weight and back fat we could estimate the mobilization and then I did that for these studies and rank them according to the lysine intake and as its expressed as the percentage of what's required for my production and maintenance going from 39 to 60 grams of lysine per day and increasing the lysine intake seems to have a small effect on and lysine yield at least some level and also we see that when we feel low why Singh we have high mobilization but the mobilization was not in high enough to to sustain a high milk production so it could indicate that that on average from early to late lactation the sows are able to mobilize between 5 and 7 grams of lysine in per day inherits this could be of course larger in some periods during a delectation turn so my point of this is that we should include and is actually the same point as a brunet did he just did it smaller I think that we should consider feed intake and performance level when we want to feed the sound if we have a feed intake of 6.7 kilo and and we wean 13 pickets with hours later gain of 3 kilos per day it corresponds to a lysine requirement approximately on 47 grams per day so the featured contain 7 grams as idealizing the same with a low feeding a slightly lower feed intake and a higher production so again then to supply this amount of life in the content in the diet should be increased and the opposite if we have a high feeding cake capacity of the cells but a low performance it should be low the exact numbers may not be realistic because I don't know the lysine in efficiency a lot of things could contribute to that for example we I I took an American and day 2 to day 28 but in early lactation requirement might be higher than the intake and the opposite in lady station so that likely effect the inefficiency of the slicing also meal frequency might affect the how much is deaminated the lysine to energy ratio the protein level and a lot of other factors but the point is that that the feed intake and the performance xi should be considered to find why what should how should we feed these sows so to sum up on this again the last letter it increases the demands and the importance of milk production and how we feed them we know that the yield is highly variable so we should feed the sounds differently a body reserve may contribute to no more than 5 to 7 grams of lysine per day on average maybe greater in some periods and we should consider a composition of the feed intake and performance as a whole so that's more of my messages just to conclude what I've already been talking about on the Left we have the sound nutrition and the letter size which we letter size which we have been changed in using genetics and we can manipulate nutrition and that's our production goals and what's in between so letter size decreases an increasingly resides decrease birth rate it decreased the amount available per piglet and in it prolong the firing process and they also interact together so being born late in in the firing process also reduce your chances to to ingest Allah enough colostrum birthweight have an impact of piglet gain and the chance of survival the same for for custom intake and the same for the feral so what we can do in terms of sound nutrition is to change meal frequency meal feed intake level and to include dietary dietary fiber this might affect pickup mortality and may affect a colostrum intake for the milk production the letter size of the little performance is a main determinant of milk yield affecting piglet gained immortality the how we feed the sow depends on how much the sound mobilized but there might be a limit on the mobilization rate but also we should use the milk yield or the piglet performance and the feed intake to determine how what should the amino acid profile be in these diets so then I would like to thank our University and especially my previous the supervisor Peter Thailand for for being responsible of a lot of this work and also my colleagues at Edinburgh and for this and thank you for your time [Applause]