We investigated changes in nitrogen metabolism and chemical, fatty acid (FA) and amino acid (AA) composition in tissues (longissimus dorsi (LD) and semitendinosus (ST) muscles, heart, spleen, liver and cecum) following the dietary addition of extruded linseed and walnut meal (50:50 mix). Plasma creatinine and urea nitrogen were determined as well. Two trials were designed using barrows (five replicates) allotted in two groups [(control, (SM) and experimental, (LEW))] in metabolic cages. The experimental diet rich in n-3 FA led to a significant increase of retained nitrogen (>8.09% in the LEW group). The biological value of feed protein was 14.8% higher in the LEW group than in the SM group. LD muscles from the SM group and liver from the LEW group had greater nitrogen contents, whereas the heart and spleen had lower concentrations of nitrogen in the LEW group. Diet had a pronounced effect on n-3 FA, particularly on α-linolenic fatty acid (ALA) (p < 0.0001). The highest levels of ALA were recorded in the cecum (>6.06 times in LEW) and heart (>5.44 times in LEW). The highest level of lysine was noticed in the LD muscle (>2.1% in SM). An n-3-rich diet significantly reduced the amount of nitrogen excreted; greater than 40% nitrogen was retained, thus improving the meat composition.

Mustard and grapeseed meals are low-cost by-products generated by the oil industry. We aimed to investigate the effects of fiber level on the concentration of volatile fatty acids (VFAs) in the ileum and cecum, as well as the microflora and enteric methane (E-CH₄) in pigs. A total of 70 Topigs hybrid pigs, 56 ± 3 days old, 20.96 ± 0.26 kg live weight, were randomly allotted to two feeding groups: (i) SM diet based on sunflower meal; (ii) MG diet based on mustard × grapeseed oil meals (MG-mixt). VFA profiles were determined by gas chromatography. E-CH₄ was calculated using our trial data along with prediction equations. The MG-mixt slightly decreased growth parameters but improved daily feed efficiency and gain cost. The MG diet increased the concentration of VFAs and the microflora level. The higher VFA level recorded in the cecum (+53.93%) was correlated with a lower pH level (Spearman correlation coefficient, rho = −0.529, p < 0.001). In relation to DM intake and energy retention, E-CH₄ recorded a highly significant decline in the MG group (<9.42%). A strong relationship was recorded among VFAs, microflora, predicted E-CH₄, and fiber and NDF intake. The VFAs could be predictors for the E-CH₄ level (p < 0.001). A significant relationship between E-CH₄ and total VFAs was noted (rho = −0.462, p = 0.04). We conclude that MG-mixt has the potential to replace sunflower meal, with the minor drawbacks being balanced by the advantages provided in terms of feed efficiency, E-CH₄ mitigation, and VFA levels.

This study shows the effects of dietary hemp seed oil on the milk composition, blood immunoglobulins (Ig), and enteric methane (E-CH₄) production of primiparous sows, and their offspring’s response at three time points. A bifactorial experiment was conducted for 21 days (d) on 18 primiparous sows (195 ± 3 days old). The sows were fed two diets: (i) a control diet (SO) based on soybean oil (1.6%), with an 18.82 n-6:n-3 polyunsaturated fatty acids (PUFA) ratio; (ii) an experimental diet (HO) based on hemp seed oil (1.6%), with a 9.14 n-6:n-3 PUFA ratio. The milk contained an elevated level of linoleic acids (LA), n-3 FA, and especially alpha-linolenic acids (ALA), while the n-6:n-3 ratio declined using hemp oil. The Ig concentration was higher in colostrum than in milk. In the first few hours, the IgG in the plasma of piglets was more than double that of maternal plasma IgG (+2.39 times). A period effect (p < 0.0001) for IgG concentration in the plasma of piglets was recorded (40% at 10 d, respectively 73% lower at 21 d than 12 h after parturition). However, the sow diet did not affect Ig (p > 0.05). The frequency of diarrhoea declined after about 7 d. The value of the rate of diarrhoea was 6.2% lower in the PHO group. We found a 4.5% decline in E-CH₄ in the HO group. Applying multiple linear regression, feed intake, n-6:n-3 ratio, ALA, and lean meat were potential indicators in estimating E-CH₄. In conclusion, sow dietary hemp seed oil increased lean meat %, milk EFA, and milk IgM. Significant changes in the other dependent variables of interest (body weight, plasma Igs in sows and offspring, E-CH₄ production) were not recorded. There was reduced diarrhoea which shows that EFA could play a therapeutic role in the incidence of diarrhoea and in lowering of E-CH₄ emission in sows and progeny. All dependent variables were significantly altered at different time points, except for fat concentration in milk and sow plasma IgG.

In this study, a comparative approach was used with the aim of filling the knowledge gap regarding the productive and economic parameters of two native B. mori silkworm breeds (Lines C and Z) fed with different diets, namely mulberry leaves alone and mulberry leaves with R. glutinis yeast at two different concentrations (1 × 10⁹ and 1 × 10⁷ CFU/mL). The trifactorial experiment was carried out with 600 silkworms during the fifth instar, with 300 for each breed and 50 larvae per rearing tray. The larvae were randomly assigned into three feeding groups, with two replicates: in the control group (C), the larvae received ordinary mulberry leaves; in the first experimental group (RG-1), the larvae were given mulberry leaves supplemented with R. glutinis yeast at a 1 × 10⁷ concentration; and in the second experimental group (RG-2), the larvae received the same quantity of mulberry leaves as the C and RG-1 groups, but with R. glutinis yeast at a 1 × 10⁹ concentration. Line C larvae in the RG-1 group revealed higher values for most of the productive traits assessed. There was a positive and significant correlation between the weights and lengths of the larvae and the silk gland, the silk gland and the shell, the cocoon and the pupae and the shell, and the shell and the pupa size (p < 0.001). The steady decline in the parameters at a higher concentration suggests that R. glutinis positively influences a number of silkworm growth features at a recommended dosage of 1 × 10⁷; however, further research is required to more precisely identify the mechanisms involved.

Solid-state fermentation (SSF) is a long-established biotechnological approach gaining renewed interest for its ability to enhance nutrient availability and improve the functional properties of agro-industrial by-products. This strategy is particularly relevant for early post-weaning piglets, which are highly susceptible to weaning stress due to an immature digestive system and a gut microbiota not yet adapted to solid feed. In this study, the fermentation parameters of flaxseed cake were optimized using a Plackett–Burman experimental design. Protease activity was selected as the response variable due to its relevance for improving protein degradation and potential digestibility in fermented feed ingredients. Accordingly, based on the statistical analysis, the conditions selected for the in vivo trial were 1% molasses, 0.5% yeast extract, 0.05% CaCl₂, 0.5% NaCl, 7.5% inoculum (4.12 × 10⁹ CFU/mL), 60% moisture, and 72 h fermentation. Fermentation time was identified as the main factor positively influencing protease production, while higher CaCl₂ concentrations and inoculum levels negatively affected enzyme activity. Optimization increased protease activity, microbial viability and free amino acid content. In addition, SSF reorganizes the carbohydrate profile by reducing structural fiber fractions, with neutral detergent fiber and acid detergent fiber decreasing by 27% and 29%, respectively, while simultaneously increasing soluble carbohydrates by 14.67%. Phytic acid content being also reduced by 23.81%. A pilot nutritional trial on post-weaned piglets (35 days old) showed that including 8% fermented flaxseed cakes (FFSC group) improved body weight, average daily gain, feed conversion ratio, and diarrhea score, without affecting average daily feed intake, compared with 8% unfermented flaxseed cakes (FSC group). These performance improvements were accompanied by changes in fermentation metabolites and gut microbial composition. Lower isovalerate concentrations suggested reduced proteolysis, while higher propionate levels may contribute to increased blood glucose availability in the FFSC group. These changes coincided with a shift in microbial composition, characterized by a reduced abundance of methanogenic archaea and increased abundances of taxa such as Lactobacillus, Enterococcus, and members of the Lachnospiraceae and Eubacteriaceae families.

The study aimed to assess the effects of including linseeds or hempseeds in the diets of late lactation Murciano-Granadina dairy goats on the nutritional quality of the milk and cheese fat, expressed by the fatty acids profile and the healthy lipid indices. Thirty-six goats were randomly distributed in 3 groups of 12 animals each, according to a 3 × 3 Latin square design, and fed three different diets: group CON (control, with sunflower meal, 11.5% DM basis); group LIN, where sunflower meal was replaced by linseed; and group HMP, where sunflower meal was replaced by hempseeds. The replacement had no effects on the milk yields and the milk protein content as no significant differences were detected among groups. The significant increase of the fat content in the case of the LIN and HMP groups was accompanied by significant decreases in saturated fatty acids concentration and very significant increases in monounsaturated fatty acids. The content of n3 and n6-PUFAs (polyunsaturated fatty acids) increased, mainly due to a 4.1 times higher proportion of alpha-linolenic acid (ALA; C 18:3n-3) in LIN diet milk and a 1.3 times higher proportion of linoleic acid (LA; C 18:2n6c) in HMP diet milk. The conjugated linoleic acid (CLA; isomer c9, t11) was 1.9 times higher for the LIN diet and 5.05 times higher for the HMP diet. Feeding either linseed or hempseeds contributed to the reduction of the atherogenic and thrombogenic indices, increased the hypocholesterolemic: hypercholesterolemic ratio as well as the proportion of other desired fatty acids in the milk fat. The improved nutritional quality of milk, which has potentially far-reaching human health benefits, is maintained in cheese through the increase of the n3 and n6-PUFAs, especially for the LIN diet where the n6/n3 ratio decreased significantly, compared with the CON diet (3.62 vs. 6.88). The CLA concentration was significantly higher (p < 0.001) for the HMP cheese compared with the CON diet (1.89% vs. 0.78%). These effects highlight the opportunity of obtaining dairy products with improved nutritional quality using local feed resources.