Wiesław Sobotka

Effect of oat by-product antioxidants and vitamin E on the oxidative stability of pork from pigs fed diets supplemented with linseed oil

The aim of the experiment was to compare the antioxidative potential of an oat by-product with the effect of vitamin E on the oxidative stability of pork from pigs fed a diet enriched with linseed oil. Thirty-four crossbreed barrows were fed individually from 39 to 109 kg body weight (BW) on one of four diets: a control diet based on barley–triticale–soybean (Diet C), a diet containing an oat by-product (Diet O), and the same diets supplemented with vitamin E (100 mg/kg diet) (Diets CE and OE, respectively). The oat by-product, comprising oat hulls and bran, was included at 10 and 20% in the grower and finisher diets, respectively. To Diets O and OE, refined rapeseed oil was added to equalise their energy content to Diets C and CE. Compared to Diets C and CE, the inclusion of the oat by-product in Diets O and OE increased the antioxidative capacity of water-soluble and lipid soluble compounds in these diets. Dietary treatment did not influence growth performance, slaughter value, longissimus dorsi (LD) muscle quality measured by nutrient contents, pH, drip loss or colour. Vitamin E supplementation increased the α-tocopherol concentration in serum and meat (p < 0.01), and decreased the formation of thiobarbituric acid reactive substances (TBARS) in the fresh and stored LD (p < 0.01). In addition, diets with the oat by-product increased serum α-tocopherol concentration (p < 0.01) and decreased the TBARS levels in the fresh and stored LD (p < 0.05), without increasing muscle α-tocopherol concentration. The obtained results indicate that the phenolic compounds present in oat by-products have a considerable antioxidant potential and a beneficial effect on the pig organism and oxidative stability of meat. However, dietary inclusion with the oat by-product was not as efficient as supplementation with vitamin E.

Periconceptional undernutrition affects in utero methyltransferase expression and steroid hormone concentrations in uterine flushings and blood plasma during the peri-implantation period in domestic pigs

Female undernutrition during early pregnancy may affect the physiological pattern of genomic DNA methylation. We hypothesised that in utero DNA methylation may be impaired in females fed a restrictive diet in early pregnancy. In this study we evaluated whether poor maternal nutritional status, induced by applying a restricted diet during the peri-conceptional period, may influence: (1) the potential for in utero DNA methylation, expressed as changes in the mRNA expression and protein abundance of methyltransferases: DNA methyltransferase 1 (DNMT1) and DNMT3a in the endometrium and the myometrium, (2) the intrauterine microenvironment, measured as oestradiol 17β (E2) and progesterone (P4) concentrations in uterine flushings and (3) plasma concentration of E2 and P4 during the peri-implantation period. Our results indicate that maternal peri-conceptional undernutrition affects maintenance and de novo DNA methylation in the endometrium, de novo methylation in the myometrium and a results in a decrease in intrauterine E2 concentration during the peri-implantation period. The intrauterine concentration of P4 and plasma concentrations of E2 and P4 did not change. These findings suggest that undernutrition during the earliest period of pregnancy, and perhaps the pre-pregnancy period, may create changes in epigenetic mechanisms in the uterus and intrauterine milieu of E2 during the peri-implantation period.

Fiber substrates in the nutrition of weaned piglets – a review

Abstract The present review summarizes the results of 37 experiments in which different types and levels (from 0.5 to 29.7%) of fibrous supplements were used in the formulation of diets for weaned piglets. Diets were supplemented with different sources of insoluble dietary fiber (iDF), soluble dietary fiber (sDF), or mixed DF sources. Most of the applied DF sources decreased the ileal and fecal organic matter digestibility, and they often lowered crude protein digestibility. A moderate addition (1.5-8%) of iDF sources increased average daily feed intake (ADFI) and, frequently, average daily gains (ADG). Sources of sDF as well as high inclusion levels of fiber-rich feeds tended to decrease ADFI and ADG. Improved fecal consistency, decreased diarrhea incidence and antibiotic interventions were confirmed in piglets fed diets with added lignocellulose, cooked or raw oat hulls and wheat bran. The dietary inclusion of iDF rather than sDF sources improved gastrointestinal tract (GIT) development, enzyme activity and gut morphology. An increase in the counts of beneficial gut microbiota and the concentrations of short-chain fatty acids was stimulated by diets with addition iDF or sDF sources. Such diets also slowed down proteolytic fermentation which negatively affects the colonic mucosa. Some research findings indicate that iDF sources improve intestinal barrier function. The analyzed experimental data suggest that the addition of 1.5-2% of a lignocellulose preparation, 2% of oat hulls, 4-8% of coarse wheat bran to diets for weaned piglets may be recommended to promote GIT development and health, and to improve growth performance.

Evaluation of the Nutritional Value of Yellow (Lupinus Luteus) and Blue Lupine (Lupinus Angustifolius) Cultivars as Protein Sources in Rats

Abstract The aim of this study was to determine the nutritional value of protein from the seeds of yellow lupine (Lupinus luteus) and blue lupine (Lupinus angustifolius) cultivars, contained in diets fed to rats. The experimental diets were based on the seeds of three yellow lupine (Mister, Markiz, Taper) or three blue lupine (Sonet, Boruta, Elf) cultivars as the only or main protein source. The nutritional value of the diets was determined based on their chemical composition and alkaloid and oligosaccharide concentrations. Lupine seeds were fed to male Wistar rats with initial body weight of approx. 112 g. Alkaloid concentrations in yellow lupine and blue lupine seeds were 0.07-0.09 g kg-1 DM and 0.26-0.39 g kg-1 DM, respectively. Oligosaccharide concentrations in yellow and blue lupine seeds were 108.0-108.9 and 65.4-67.6 g kg-1 DM, respectively. The inclusion of lupine seeds in rat diets increased fecal and urinary nitrogen losses, and decreased nitrogen retention by approx. 10%. The diets based on yellow or blue lupine seeds were characterized by lower nitrogen digestibility and lower biological value of protein than the control diet containing casein.

Effect of feed structure on nutrient digestibility, growth performance, and gastrointestinal tract of pigs – A Review

Abstract The objective of this manuscript has been to analyse published data on the effect of feed structure (coarse/fine, meal/pelleted) on some parameters of the nutritional value of feed, performance of pigs and their gastrointestinal tract. The papers reporting mean geometric particle size or distribution of particles on sieves for the feeds used, were mainly considered. The literature data have indicated that finely ground feeds have a higher ileal digestibility of crude protein and amino acids and higher faecal digestibility of nutrients. They also contain more digestible and metabolisable energy than coarser ground feeds. Reduction of feed particle size has a stronger impact on the gain/feed ratio increase than on the daily gain of pigs. However, coarser feed structure and roller milling are efficient in maintaining the health of stomach. Lactic bacteria, stomach pH, short chain fatty acids in the gastrointestinal tract (GIT), as well as the volume and character of mucins positively responded to coarser and to non-pelleted feeds. Less intensively ground feeds, especially before pelleting, are also better at protecting the GIT of pigs against microbial infection by Salmonella enterica. Based on the references, some recommendations of grinding intensity have also been included.