Fats and oils in pig nutrition: Factors affecting digestion and utilization

Lipid analysis of breast milk and formula for preterm infants and the application and prospects of novel structural lipids - a comprehensive review

Preterm infants, often characterized by lower birth weights and underdeveloped physiologies, necessitate specialized nutritional care. While breast milk stands as the ideal nutritional source, offering substantial energy through its fatty acid content to support the infants' growth and developmental needs, its usage might not always be feasible. Fatty acids in breast milk are critical for the development of these infants. In scenarios where breast milk is not an option, formula feeding becomes a necessary alternative. Thus, a comprehensive understanding of the fatty acid profiles in both breast milk and formulas is crucial for addressing the distinct nutritional requirements of preterm infants. This paper aims to summarize the effects of lipid composition, structure, and positioning in breast milk and formula on the growth and development of preterm infants. Furthermore, it explores recent advancements in the use of novel structural lipids in formulas, laying the groundwork for future innovations in formula design specifically catered to the needs of preterm infants.

Variation in body weight, glucose/insulin tolerances, blood lipids and liver enzymes in mice in response to a high-fat-diet from lard

It raises questions about the impact of lard on the health and the differences in individual responses. Therefore, we developed a model of mice fed with high fat (HF) from lard in 130 days. The weight of the mice was measured every two days. Glucose tolerance test and insulin tolerance tests were performed at 70 days and 130 days of experiment. At the end of the study, the fat tissue was collected to check the weight, and a blood sample was collected to check the blood lipids and liver enzymes. Surprisingly, mice responded variously to the HF by being classified into two groups, one group had significantly high gained weight (HG_HF) versus the mice fed a standard diet (STD) (p < 0.001), and another group (LG_HF) has not difference in body weight compared to the STD groups. This phenomenon in body weight is directly reflected by the white fat accumulation, but not by brown fat. Eating HF from lard for a long time can disrupt glucose tolerance and cause dyslipidemia in mice, even in the LG_HF group, but can not disrupt insulin tolerance and cause liver enzyme disorders. In summary, our findings are a wake-up call for many cases where eating HF from lard does not gain weight and not increase the white fat storage, but still has the potential to cause adverse health effects. Further studies are encouraged to understand the molecular mechanisms that causes the body to regulate its weight and responses when eating HF from lard, especially in the LG_HF group.

Brazilian Corn Ethanol Coproducts for Pigs: Feeding Value and Blood Parameters

This study aimed to determine the values of net energy (NE), digestible energy (DE) and metabolizable energy (ME) and digestibility coefficients of corn ethanol coproducts produced in Brazil and their effects on the nitrogen balance and blood parameters of pigs. Ten barrows were housed in metabolic study cages for total collection and fed a reference diet (RD) or 800 g/kg RD + 200 g/kg of a coproduct of corn ethanol. Distiller's dried grains with solubles (DDGS), corn bran with solubles (CBS), distiller's dried grains (DDG) and high-protein distiller's dried grain (HPDDG) were evaluated. The experimental design was randomized blocks with three repetitions per period, totaling six repetitions per diet. Diets containing the HPDDG had greater DE and ME than those containing CBS and DDGS and greater DE than those containing the DDG (p < 0.05). HPDDG, DDG, CBS and DDGS showed 4498, 3419, 3029 and 3335 kcal/kg DE; 4366, 3305, 2934 and 3214 kcal/kg ME; and 2515, 1938, 1649 and 1725 kcal/kg NE, respectively. Pigs fed diets containing HPDDG and CBS showed greater nitrogen retention efficiency than pigs fed DDGS (p < 0.05). Pigs fed diets containing HPDDG had higher blood urea levels than pigs fed CBS and RD, while triglyceride levels in animals that received the CBS diet were greater than those in animals that received all other diets. The HPDDG had the highest energy levels and the best digestibility coefficients. The chemical composition of coproducts influences the nitrogen balance and circulating levels of urea and triglycerides in pigs.

Dietary fat and high energy density diet: Influence on intestinal health, oxidative stress and performance of weaned piglets

The utilization of dietary components to support gut function and the health of young animals is an important factor for improved performance. The influence of high dietary fat levels in a low or high energy density diet on the performance of weaned piglets in relation to intestinal absorptive function, amino acid utilization, oxidative stress, and microbial metabolites was assessed in this study. The study examined the effect of two different diets containing either a low energy density/high-fat level or a high energy density/high-fat level. A total of 16 healthy weaners (9.60 ± 0.13 kg) were allocated to one of the two dietary treatments. There were eight weaners per treatment. Results showed that feed intake and body weight gain of weaners were increased by the diet of high energy density/high-fat level (p < 0.05), but the feed efficiency showed an increased tendency of significance (p = 0.05). In the duodenum, the villus height (VH) and VH/crypt depth (CD) ratio (VH:CD) were increased by dietary high energy density/high fat. In the jejunum and ileum, the CD was increased by low energy density/high-fat diet, while the goblet cell count and VH:CD were increased by dietary high energy density/high-fat level. Methionine, lysine and phenylalanine concentrations were increased by high energy density/high-fat diet while low energy density/high-fat diet showed an increased tendency to increase citrulline and ornithine concentrations in the piglet. Oxidative stress marker, lactase enzyme activity and serum calcium concentration were increased by a high energy density/high-fat diet. Increased dietary fat in all diets induced diarrhoea in the weaners (p < 0.01). It was concluded that a dietary high energy density/high-fat diet seems to positively modulate gut absorptive function, serum amino acid (methionine and lysine), calcium levels and increased oxidative stress markers in the weaned piglets.

Oils with different degree of saturation: effects on ileal digestibility of fat and corresponding additivity and bacterial community in growing pigs

BACKGROUND

Oils are important sources of energy in pig diets. The combination of oils with different degree of saturation contributes to improve the utilization efficiency of the mixed oils and may reduce the cost of oil supplemented. An experiment was conducted to evaluate the effects of oils with different degree of saturation on the fat digestibility and corresponding additivity and bacterial community in growing pigs.

METHODS

Eighteen crossbred (Duroc × Landrace × Yorkshire) barrows (initial body weight: 29.3 ± 2.8 kg) were surgically fitted with a T-cannula in the distal ileum. The experimental diets included a fat-free basal diet and 5 oil-added diets. The 5 oil-added diets were formulated by adding 6% oil with different ratio of unsaturated to saturated fatty acids (U:S) to the basal diet. The 5 oils were palm oil (U:S = 1.2), canola oil (U:S = 12.0), and palm oil and canola oil were mixed in different proportions to prepare a combination of U:S of 2.5, 3.5 and 4.5, respectively.

RESULTS

The apparent and standardized ileal digestibility (AID and SID) of fat and fatty acids increased linearly (P < 0.05) as the U:S of dietary oils increased except for SID of fat and C18:2. The AID and SID of fat and fatty acids differed among the dietary treatments (P < 0.05) except for SID of unsaturated fatty acids (UFA) and C18:2. Fitted one-slope broken-line analyses for the SID of fat, saturated fatty acids (SFA) and UFA indicated that the breakpoint for U:S of oil was 4.14 (R2 = 0.89, P < 0.01), 2.91 (R2 = 0.98, P < 0.01) and 3.84 (R2 = 0.85, P < 0.01), respectively. The determined SID of fat, C18:1, C18:2 and UFA in the mixtures was not different from the calculated SID of fat, C18:1, C18:2 and UFA. However, the determined SID of C16:0, C18:0 and SFA in the mixtures were greater than the calculated SID values (P < 0.05). The abundance of Romboutsia and Turicibacter in pigs fed diet containing palm oil was greater than that in rapeseed oil treatment group, and the two bacteria were negatively correlated with SID of C16:0, C18:0 and SFA (P < 0.05).

CONCLUSIONS

The optimal U:S for improving the utilization efficiency of mixed oil was 4.14. The SID of fat and UFA for palm oil and canola oil were additive in growing pigs, whereas the SID of SFA in the mixture of two oils was greater than the sum of the values of pure oils. Differences in fat digestibility caused by oils differing in degree of saturation has a significant impact on bacterial community in the foregut.

Resveratrol alleviates oxidative stress induced by oxidized soybean oil and improves gut function via changing gut microbiota in weaned piglets

BACKGROUND

Oxidized soybean oil (OSO) has been shown to impair growth and exacerbate inflammation, leading to intestinal barrier injury in animals. Recent evidence suggests important roles for resveratrol (RES) in the promoting growth performance, antioxidant capacity, anti-inflammatory, and regulate intestinal barriers in animals. Therefore, The objectives of this study are to investigate the effects of dietary RES (purity 98%) supplementation on the growth performance, antioxidant capacity, inflammatory state, and intestinal function of weaned piglets challenged with OSO.

METHODS

A total of 28 castrated weaned male piglets with a similar body weight of 10.19 ± 0.10 kg were randomly assigned to 4 dietary treatments for 28-d feeding trial with 7 replications per treatment and 1 piglet per replicate. Treatments were arranged as a 2 × 2 factorial with oil type [3% fresh soybean oil (FSO) vs. 3% OSO] and dietary RES (0 vs. 300 mg/kg).

RESULTS

The results showed that relative to the FSO group, OSO stress tended to decrease the average daily feed intake (ADFI), and decreased the activity levels of lipase, villus/crypt ratio (VCR), the mRNA expression of FABP1, SOD2, IL-10 and ZO-1 in the jejunum, and SOD2, GPX1, occludin and ZO-1 in the colon, the levels of acetic acid in the colonic digesta, whereas up-regulated the mRNA expression of IL-1β and TNF-α in the jejunum (P < 0.05). Moreover, dietary supplementation with RES increased ether extract (EE), the activity levels of sucrase, lipase, α-amylase, villus height (VH) and VCR, the mRNA expression of FABP1, SOD2, IL-10 and occludin in the jejunum, and FABP1, PPAR-γ, GPX1, occludin and ZO-1 in the colon, and the abundance of Firmicutes, acetic and propionic acid, but decreased the levels of D-lactic acid in the plasma, the abundance of Bacteroidetes in the colonic digesta of weaned piglets compared to the non-RES group (P < 0.05). Meanwhile, in the interaction effect analysis, relative to the OSO group, dietary RES supplementation in the diets supplemented with OSO increased the activity levels of trypsin, VH in the jejunum, the abundance of Actinobacteria, the levels of butyric acid of weaned piglets, but failed to influence the activity levels of trypsin and VH, Actinobacteria abundance, the levels of butyric acid when diets were supplemented with FSO (interaction, P < 0.05). Relative to the OSO group, dietary RES supplementation in the diets supplemented with OSO decreased the activity levels of DAO in the plasma of weaned piglets but failed to influence the activity levels of DAO when diets were supplemented with FSO (interaction, P < 0.05). Relative to the FSO group, dietary RES supplementation in the diets supplemented with FSO decreased the level of propionic acid, whereas RES supplementation failed to influence the level of propionic acid when the diet was supplemented with OSO (interaction, P < 0.01).

CONCLUSIONS

Inclusion of OSO intensified inflammatory states and impaired the intestinal health characteristics of weaned piglets. Dietary RES supplementation improved the antioxidant capacity, anti-inflammatory activity, and intestinal morphology. Further studies showed that the protective effects of RES on gut health could be linked to the decreased abundance of Prevotella_1, Clostridium_sensu_stricto_6, and Prevotellaceae_UCG003 and increased levels of acetic and propionic acid.

Effect of a Combination of Lysolecithin, Synthetic Emulsifier and Monoglycerides on the Apparent Ileal Digestibility, Metabolizable Energy and Growth Performance of Growing Pigs

Two studies were conducted to determine the impact of an absorption enhancer containing a combination of lysophospholipids, monoglycerides and synthetic emulsifiers (LEX) on apparent ileal digestibility, metabolizable energy (ME), and growth performance of growing pigs. In the digestibility study, 12 male crossbred [Duroc x (Large White x Landrace)] pigs with an initial body weight (BW) of 30 kg were randomly allocated to two dietary treatments: (1) a positive control (PC) receiving standard diets formulated to 3100 kcal ME/kg, and (2) a negative control formulated with −100 kcal ME/kg and −2.5% AA content vs. PC and supplemented with LEX at 500 g/t. Apparent ileal digestibility of essential AA was significantly increased for lysine, methionine, threonine, histidine, isoleucine and phenylalanine in the LEX treatment (p < 0.05). Average uplift in AA digestibility as a percent of the PC was +1.88%; with greatest improvement for histidine (+4.22%). LEX supplementation effectively compensated energy deficiency of low-density diet and provided additional ME improvement compared to the PC diet (p < 0.05). A second study was conducted to evaluate LEX dose response on the growth performance of pigs fed a low nutrient density diet. Total 450 cross-bred pigs (240 males (castrated) and 210 females) [Duroc x (Large White x Landrace)] with an average initial BW of 7.19 kg were randomly allocated into 4 dietary treatments: (1) a positive control (PC) formulated with standard specifications, (2) a negative control formulated with −100 kcal ME/kg and −2.5% AA content vs. the PC (NC), (3) NC + LEX at 250 g/t (NC + 250) and (4) NC + LEX at 500 g/t (NC + 500). Results showed significant improvement with LEX supplementation on the final BW, average daily gain (ADG) and feed conversion ratio (FCR) of pigs of >50 kg body weight. Across the study, NC + 500 significantly increased ADG vs. PC and NC, and significantly reduced FCR compared to all other treatments. FCR of negative control diets improved by 9 and 15 points with the supplementation of 250 g/t and 500 g/t of LEX, respectively (p < 0.05). FCR in the NC + 250 diet was statistically similar vs. PC, which was significantly reduced compared to the NC. Taken together, these studies demonstrate that the addition of an absorption enhancer containing a combination of lysophospholipids, monoglycerides and synthetic emulsifiers can improve growth performance in growing pigs, driven by increased nutrient digestibility and retention.

Effects of dietary oil sources and fat extraction methods on apparent and standardized ileal digestibility of fat and fatty acids in growing pigs

Background

There is a lack of data for the standardized ileal digestibility (SID) of fat and fatty acids in national feed databases. In addition, it is important to specify the procedures used for fat analyses. Therefore, an experiment was conducted to 1) determine the apparent ileal digestibility (AID) and SID of fat and fatty acids in ten different oil sources for growing pigs and to develop prediction equations for SID of fat based on fatty acid composition; and 2) compare the effect of the fat extraction methods on the calculated values for endogenous loss and digestibility of fat.

Methods

Twenty-two barrows (initial body weight: 32.1 ± 2.3 kg) were surgically fitted with a T-cannula in the distal ileum, and allotted to 1 of 11 experimental diets in a 4-period Youden Square design. A fat-free diet was formulated using cornstarch, soy protein isolate and sucrose. Ten oil-added diets were formulated by adding 6% of dietary oil sources to the fat-free diet at the expense of cornstarch. All diets contained 26% sugar beet pulp and 0.40% chromic oxide.

Results

The endogenous loss of ether extract (EE) was lower than that of acid-hydrolyzed fat (AEE; P < 0.01). There were significant differences in the AID and SID of fat and saturated fatty acids across the dietary oil sources (P < 0.05). The SID of AEE for palm oil was lower than that of sunflower oil, corn oil, canola oil, rice oil and flaxseed oil (P < 0.01). The AID and SID of fat ranged from 79.65% to 86.97% and from 91.14% to 99.18%. Although the AID of EE was greater than that of AEE (P < 0.01), there was no significant difference in SID of EE and AEE except for palm oil. The ratio of unsaturated to saturated fatty acids (U/S) had a positive correlation with SID of fat (P < 0.05), whereas C16:0 and long chain saturated fatty acids (LSFA) were significant negatively correlated with SID of fat (P < 0.01). The best-fit equation to predict SID of fat was SID AEE = 102.75 − 0.15 × LSFA − 0.74 × C18:0 − 0.03 × C18:1 (Adjusted coefficient of determination = 0.88, P < 0.01).

Conclusions

When calculating the SID of fat, the EE content of the samples can be analyzed using the direct extraction method, whereas the acid hydrolysis procedure should be used to determine the AID of fat. Fat digestibility of dietary oils was affected by their fatty acid composition, especially by the contents of C16:0, LSFA and U/S.

A Mix of Dietary Fibres Changes Interorgan Nutrients Exchanges and Muscle-Adipose Energy Handling in Overfed Mini-Pigs

This study evaluates the capacity of a bread enriched with fermentable dietary fibres to modulate the metabolism and nutrients handling between tissues, gut and peripheral, in a context of overfeeding. Net fluxes of glucose, lactate, urea, short chain fatty acids (SCFA), and amino acids were recorded in control and overfed female mini-pigs supplemented or not with fibre-enriched bread. SCFA in fecal water and gene expressions, but not protein levels or metabolic fluxes, were measured in muscle, adipose tissue, and intestine. Fibre supplementation increased the potential for fatty acid oxidation and mitochondrial activity in muscle (acox, ucp2, sdha and cpt1-m, p < 0.05) as well as main regulatory transcription factors of metabolic activity such as pparα, pgc-1α and nrf2. All these features were associated with a reduced muscle fibre cross sectional area, resembling to controls (i.e., lean phenotype). SCFA may be direct inducers of these cross-talk alterations, as their feces content (+52%, p = 0.05) was increased in fibre-supplemented mini-pigs. The SCFA effects could be mediated at the gut level by an increased production of incretins (increased gcg mRNA, p < 0.05) and an up-regulation of SCFA receptors (increased gpr41 mRNA, p < 0.01). Hence, consumption of supplemented bread with fermentable fibres can be an appropriate strategy to activate muscle energy catabolism and limit the establishment of an obese phenotype.