Hello, everyone. My name is Jimena Ibagon and I am a Visiting scholar working with Dr. Hans Stein at the University of Illinois.

Our lab focuses on determinating values of digestibility of energy and nutrients and today I am going to talk about how Sunflower expellers (SFE) have greater ileal digestibility of amino acids than sunflower meal (SFM) when fed to growing pigs.

So to begin with, I would like to discuss sunflower and the importance of conducting research using it.

Over the past few years, sunflower oil is extracted from sunflower seed mainly for human food consumption. An important fact about the position of SF in the oil industry and feed industry is that in 2020, global sunflower seed production was to be around 54 million metric tons, making it to be the third most produced oilseed around the world after soybeans and rapeseed. Noticeably, sunflower seed has a high content of oil, therefore, oil production from SF has reached 19 million metric tons during the last 5 years, and SFM as another important by product of sunflower seeds has been trending up 22 million metric tons in the Global production. Countries including Ukraine, Russia, and the European Union are the largest producers of sunflower seeds, but we can include based on USDA data countries, as U. S. and Argentina than have a significant production as well.

There are two important methods of oil extraction in sunflower meal and one of them is the expeller pressing method that I am going to further explain using this schematic representation. 

The process starts with the cleaning and storage of the seeds, followed by the de-hulling process. The de-hulling process involves partial or total removal of the hulls from the seeds and this is a very important step because it affects the final quality of the meal because of the high fiber content on those hulls. 

After that, we have the crushing rolls, which is the first press of the sunflower seeds, and then the seeds are going through the final pressing which sometimes involves high temperatures because of the friction. After that, we finally obtained the sunflower expeller. In some crushing plants there are just one pressing step before to obtain the oil. 

After the meal is separate from the oil, the oil is being filtered and centrifuged to be de-gummed. Sometimes these gums are added back to the meal in the final process, but this step may vary among processing plants.  After that, the oil is ready for the final purpose. 

The second oil extraction method is the solvent extraction process, which is the continuation of the expeller pressing process but to this process, the solvent extractor is added. So, after the first crushing of the seed, and in some crushing plants after the second one crushing, the seeds are going through the solvent extractor, and this step is to obtain more oil from the meal, the meal is being desolventized to finally obtained the sunflower meal.

Therefore, those are the differences in the processing and the way to obtain those co-products and basically the difference between sources could be the addition of the third step which involves the solvent extraction.

Talking about sunflower co products, we can say that sunflower meal is one of the most important co products of sunflower seeds. This is because it has many good characteristics which makes it an ideal by product to feed pigs.

First of all, SFM has been used as an alternative and less expensive source of AA than Soybean meal (SBM), which can be fed to pigs and poultry. 

However, even if we know that SFM has a high content of protein, the nutritive value and quality of the meal may vary due to variation in climate conditions, soil, cultivation methods, place of growing and difference in the oil extraction process.

One of the most important steps, which may affect the composition or quality of the final SFM, is the degree of de-hulling or the addition of hulls back to the meal in the oil extraction process, which may increases fiber content in SFM, therefore 

To  move on to the objective of this experiment, we decide to test the hypothesis that there is no effect of growing region on SID of AA in SFM and that SID of AA in SFM are not different from values obtained in SFE.

Now let’s move on to the materials and methods that we used to conduct this experiment. We had a eight by eight Latin square design with 8 periods and 8 diets, and as an experimental unit we had 8 cannulated barrows with an initial body weight of 28 kilo approximately, and for the sample collection we had a 7 day period with 5 days of adaptation and 2 days of ileal digesta collection. 

Collecting the samples is very straight forward, we simply take out the cap of the canula as you can see in the photo on the bottom right and then put a plastic bag on the cannula and then the ileal digesta just flows through, and the we are able to collect that and analyzed for nutrients.

So now I would like to quickly explain to you the diets that we used for this experiment. We used the SFM and the SFE as a whole source of protein in each diet. We had 4 different regions of origin, that you  can see in the slide and we receive 2 SFM from the United States, 2 from Ukraine and 1 from Hungary and 1 from Italy, the SFE was received from the U. S. and this it was to complete 7 ingredients for 7 diets and finally we had an eight diet and it was the n-free diet, and it was made up from corn starch and sucrose which means that it was devoid of amino acids, so we use it to calculate standardized ileal digestibility by determining the basal endogenous losses. We used chromic oxide for all of diets as an indigestible marker. 

So finally, once we had all of our analysis complete and we had our data, we analyzed it in SAS with the mixed procedure. For this analysis, we used 2 models; for the first one, we had as a main effect the SFM sources and pig and period as the random effect, and for the second one, to compare SFE with SFM sources we used a contrast statement. 

Let’s move on to the results, and I want to start by taking about some nutritional characteristics, 

But before to start, I would like to set up my slides. As you can see for sunflower meal we have in light and dark blue sources from U.S, in yellow and orange we have sources from Ukraine, and in light and dark grey we have sources from Hungary and Italy respectively, and finally in the right side of the slide we can find the SFE in light green. So to begin with, I'd like to look at Acid hydrolyzed ether extract, and we observed big differences in terms of fat content among SFM sources, it could be attributed to the addition of gums during the oil extraction process to the meal by the end of the process, resulting in the increased oil concentration. Likewise we can see a big difference in the concentration of fat in the SFE compare with SFM sources and it is due to the absence of the solvent extraction step in the oil extraction process to obtain it. 

For Gross energy, we did not observe big differences in SFM sources, but for SFE we observed a greater concentration of energy and it is because there is positive correlation between energy and acid hydrolyzed ether extract.

So if we look at total dietary fiber, we observed some variations among SFM sources, and it could be possible because of the de-hulling process, that is dependent on the process of each refining plant. However, we can observe that SFE has greater concentration of total dietary fiber (TDF) as well, even more than some of SFM sources. 

In addition, this is reflected in the concentration of crude protein, we can see the negative correlation between fiber and protein in this slide, and some of the SFM sources with high concentration of fiber, had lower concentration of protein, including the SFE, and it is because higher concentrations of fiber in the diet may release lower concentrations in crude protein.  

Moving on to the results of digestibility of amino acids, when we look at the 4 limiting amino acids, we did not observe any differences in the standardized ileal digestibility of the Lys among SFM sources, but we observed a significant difference in the digestibility of Lys for SFE compared with SFM.

Similar results for the digestibility of Methionine, we did not have any differences among SFM but we had a significant greater digestibility of Methionine in SFE compared with SFM sources.

However, for threonine, we observed that the source from Hungary had a significant lower digestibility compared with the sources from U.S, Italy and for one of the source from Ukraine and for SFE we observed a significant greater digestibility of threonine compare with sunflower meal.

And finally, for Tryptophan, we did not find any significant difference between SFE and SFM sources, and even we didn’t find any significant difference among SFM sources.

Finally, to conclude, in terms of nutritional characteristics the concentration of CP and fiber varies among SF co-products and it could be mainly due to the differences in process. In terms of Digestibility only a minor impact of region was observed in the SID of AA.

And in addition, we observed that the standardize ileal digestibility of AA in SFE was greater than in SFM sources, and it could be because of the concentration of fat in the expeller which reduce the rate of passage in the intestinal tract, enhancing the abortion of nutrients.

So with that I would like to acknowledged to Cargill Inc., for the funding and the support, and of course everybody in the Stein Monogastric nutrition group for the help in this project and to you thank you for your attention and if you have any questions or would like another information about the work that we are doing in our group feel free to reach out and visit our website at nutrion.ansic.illinois.edu. Thank you.