The rearing of piglets is the most difficult period in the pigs’ production because of their poorly developed digestive system and the low activity of digestive enzymes. Problems in nutrition and stress cause some disorders in the functioning of the digestive system leading to diarrhea and the mortality of piglets. Starting in 2006 in the EU, a total ban on antibiotics in their use as growth promoters was introduced. Since then, new and safe feed additives have been sought in order to replace antibiotics. Organic and inorganic acids as well as their salts were recognized as effective and safe additives. Due to their properties, they can improve feed palatability and digestibility, reduce the buffer capacity of feed, impact the development and functioning of the pig’s digestive system and improve the health and growth parameters. However, the effectiveness of acids is related to their qualitative and quantitative share in the feed additive. In this review, some strategies for using organic acids, their mixtures and also some new multi-component products will be discussed.

The objective of the study was to determine the effect of replacing soybean meal with 5% of raw soybean seeds on the growth, feed consumption and utilization of growing pigs, also the carcass and pork quality. The growth experiment was conducted on 120 pigs of approx. 18.5 kg allocated to two dietary treatments. The animals from the control treatment (CON) were offered a diet with soybean meal, and the experimental group (EXP) was given 5% raw soybean seeds (NON-GMO, Augusta var.) instead of SBM. The experiment lasted 88 days. After the experiment, eight pigs from each group were euthanized and meat samples were collected. No diet effects on the animals’ performance and carcass quality were observed (P>0.05). The experimental diet affected (P<0.05) meat color, and also meat composition (higher water content and lower intramuscular fat content). The composition of fatty acids in the meat did not differ significantly, except for higher C16:1 content in the EXP group. The introduction of 5% raw soybean seeds into the diets did not impact animal performance, but it reduced some indices of the pork quality.

The aim of this study was to compare the chemical composition of European soy seeds. A mycological and toxigenic screening was carried out on 18 varieties of soy seeds harvested in Poland. Moreover, the level of soybean meal (SBM) substitution by raw soybean seeds was analysed in terms of its effect on young pigs’ performance (body weight gain, feed intake, feed utilisation) along with apparent total tract digestibility (ATTD) of dry matter and crude protein in the diets. In a 28-day trial, 48 male pigs were tested using a marker method with TiO2. In their diets, SBM was replaced by soy seeds in the amounts of 0%, 5%, 10%, 15%, 20% and 25%. In the last 3 days of the experiment, samples of excreta from each animal separately were collected three times per day. The chemical composition of soybean seeds differed in terms of their contents of crude protein, ether extract, neutral detergent fibre and raffinose family oligosaccharides, as well as the trypsin inhibitor activity. Seeds were also contaminated with fungi, yeast and mycotoxins, mainly zearalenone and deoxynivalenol. The ATTD of crude protein ranged from 70.6% to 77.6% and that of dry matter from 93.5% to 94.6%, with no differences between the groups being found (p > 0.05). Pigs’ performance parameters were reduced strongly with increasing amounts of raw seeds in the diets (p < 0.05). The results indicate that only a 5% addition of raw soy seeds in pigs‘ diet is recommended.

The aim of this study was to: (1) provide controlled fermentation of narrow-leafed lupine seeds; (2) monitor seed composition, and (3) determine the influence of fermentation on the performance, gut environment and physiology, and selected blood metabolic parameters, in young pigs. Firstly, the effect of 24 h lupine seed fermentation by bacteria and yeast on seed chemical composition was determined. It increased contents of crude protein, crude fiber and ash, but reduced nitrogen-free extractive levels. The amino acid profile of fermented lupine (FL) was similar to that of raw lupine (RL) seeds, whereas the contents of oligosaccharides and P-phytate decreased significantly, in contrast to alkaloids. In fermented feed, pH dropped from 5.5 to 3.9. In the 28-day experiment, 24 male pigs were divided into three groups. The control group was fed a soybean meal diet (SBM), whereas in the experimental diets, 50% of SBM protein was replaced by RL or FL. Afterwards, eight pigs from each group were euthanized and their digesta and blood samples were collected. The FL use did not affect pigs’ performance, nor their metabolic, microbial and most gastrointestinal tract parameters, but influenced crypt depth. Fermentation affected concentrations of short chain fatty acids and p-cresole in the proximal colon segment. In the small intestine, the levels of acetate and butyrate decreased, and, in the caecum, the propionate level decreased. Fermentation significantly lowered the pH of the middle colon digesta and ammonia contents compared to RL. A part of SBM may be successfully replaced by RL and FL in young pigs’ diets.

The study was conducted to evaluate the effects of partial replacement of soybean meal (SBM) by 15% raw or fermented rapeseed cake (RRC or FRC) to broilers’ diets on growth performance, nutrient utilization, methane emission, and breast muscle fatty acid (FA) composition. A total of 420 one-day-old female Ros 308 broilers were used in three independent experiments (300 birds in the first experiment and 60 in the second and third experiments). In each trial, three treatments were set up: a control group (without rapeseed), and diets replaced soybean meal with 15% addition of RRC or FRC. Birds fed the FRC diet experienced no effect (p > 0.05) on performance or nutrients utilization. Methane emission and total methanogen population in the ceca was decreased (p < 0.05) with the FRC diet. The concentrations of n-3 and n-6 FAs in the breast tissue of fourteen-day-old birds were not affected (p > 0.05) by FRC. However, the n-6/n-3 ratio in the breast muscle of 28-day-old birds was reduced (p < 0.001). In conclusion, the replacement of SBM by FRC in the broiler diets did not show any unfavorable effects on performance or nutrient utilization. Furthermore, the breast meat FA profile was improved, methanogen counts significantly decreased, and methane emission was limited.