Joao P.B. Freire

Effect of dietary fibre source on total tract digestibility, caecum volatile fatty acids and digestive transit time in the weaned piglet.

Effects of the use of 200 g of either wheat bran, sugar beet pulp, soya bean hulls or alfalfa meal per kilogram diet on the digestive process of the weaned piglet were studied on 24 Duroc Landrace male piglets, weaned at 28 days of age. Piglets had an initial mean live weight of 7.92(1.1) kg and were randomly distributed in six successive blocks of four animals. The total tract apparent digestibility (TTAD) was 0.872, 0.887, 0.815 and 0.824 for energy and 0.847, 0.833, 0.665 and 0.795 for nitrogen for the wheat bran, sugar beet pulp, soya bean hulls and alfalfa meal diet, respectivelyOP < 0:01U. The TTAD values for NDF were 0.615, 0.861, 0.721 and 0.593, and for ADF were 0.390, 0.779, 0.708 and 0.457 in diets based on wheat bran, sugar beet pulp, soya bean hulls and alfalfa meal, respectivelyOP < 0:01U. The level of volatile fatty acids (VFAs) in the caecum contents changed from 3.80 to 4.96 mg g ˇ1 when sugar beet pulp replaced soya bean hulls, respectively, the later producing a higher proportion of acetic acidOP < 0:05U. The average molar proportions were 0.635, 0.245 and 0.10 for acetic, propionic and butyric acid, respectively. Soya bean hulls in the diet increased the level of total VFA by 15 or 30% when compared with the wheat bran or with the sugar beet pulp and the alfalfa meal, respectively OP < 0:05U. For a constant nitrogen intake, the diet containing soya bean hulls supported the lowest nitrogen retention. The mean retention time was 51.5, 49.9, 56.9 and 37.7 h for diets based on wheat bran, sugar beet pulp, soya bean hulls and alfalfa meal, respectively OP < 0:01U. In contrast to alfalfa meal, the soya bean hulls reduced the chromium excretion rate by 40% and delayed the inflexion point of the excretion curve by 11 h, and consequently the digestive transit time. In conclusion, sugar beet pulp has the highest degradation rate of NDF and ADF fractions. The inclusion of soya bean hulls leads to a decrease in the energy and nitrogen digestibility of the

Comparative effects of different legume protein sources in weaned piglets : nutrient digestibility, intestinal morphology and digestive enzymes

Abstract A total of 30 male piglets (Duroc×Landrace) weaned at the 28th day of age were used to compare the nutrient digestibility of legume seeds and their impact on digestive enzyme activities and morphology of intestinal mucosa sampled at slaughter. Five groups of six piglets were fed a control (C) diet based on casein or a diet in which 50% of crude protein (CP) were supplied by soya bean meal (SBM), pea (P), faba beans (FB), or blue lupin ( Lupinus angustifolius ) (L), respectively. Total tract (TTAD) and ileal (IAD) apparent digestibilities were measured on the same piglets between the 32nd–39th day and 53rd–60th day of age, respectively. TTAD and IAD of DM, CP and energy were lower in legume-containing diets as compared to the control diet. Among the legume seeds, the lupin-based diet had the lowest TTAD and IAD of DM and energy, but no significant differences were found for the IAD of CP. The height of intestinal villi was the highest with SBM and the lowest with FB only in the duodenum. Crypt depth increased by 50% in the piglets fed the P and FB diets, as compared to controls. Pancreas weight was higher and the duodenal activities of most intestinal enzymes examined were lower with the legume-containing diets.

Comparative effects of dietary fat and fibre in Alentejano and Large White piglets: Digestibility, digestive enzymes and metabolic data

Abstract An experiment involving 24 Large White (LW) and 24 Alentejano (AL) piglets weaned at 21 days of age was conducted to study the effects of dietary fat and fibre on digestive capacity, and metabolic parameters in both genotypes, according to 2×2×2 factorial arrangement, with two genotypes, two levels of fibre (0 or 15% of wheat bran) and two sources of fat (olive oil or beef tallow). Total tract apparent digestibility (TTAD) was measured and blood samples were taken at fasting and throughout 5 h after meal. Average TTAD in AL and LW piglets, respectively, were 80.2 and 77.9% for energy, 69.4 and 61.4% for fat, 63.0 and 52.6% for NDF, and 39.8 and 13.1% for ADF. Wheat bran reduced TTAD of energy, fat and ADF by 5, 10 and 10 percentage units, respectively, in LW breed, and by 2, 10 and 4 percentage units, respectively, in AL breed. Total activities of pancreatic lipase, trypsin and amylase, and intestinal maltase at 49 d of age were 2.0, 1.5, 5.0 fold and 60% higher, respectively, in Alentejano piglets. For a constant nitrogen intake, daily nitrogen retention was greater in LW than in AL piglets, i.e., 6.7 vs. 5.8 g d −1 , respectively. The maximum serum urea level was observed, 4 h after the meal, for diets containing wheat bran, i.e., 66.1 mg/100 ml and 53.1 mg/100 ml in AL and LW piglets, respectively, but LW breed exhibited higher levels of triglycerides, HDL-cholesterol and LDL-cholesterol.

Lupinus luteus, Vicia sativa and Lathyrus cicera as protein sources for piglets: ileal and total tract apparent digestibility of amino acids and antigenic effects

Abstract Twenty-four male piglets, weaned at 28 days of age, were used to measure the total and ileal digestibility and serum immune responses to dietary leguminous seeds. The experimental diets consisted of a control starter (C) and three other diets prepared by replacing 30% of the crude protein content of the C diet by the protein of Lupinus luteus (LL), Vicia sativa (VS) or Lathyrus cicera (LC). The total tract apparent digestibility (TTAD) of energy and crude protein (CP) was lowest ( P P L. luteus , vicilin of V. sativa and vicilin of L. cicera were detected 28 days after feeding the diet in the sera of piglets fed on the LL, VS or LC diets, respectively. Conversely, no storage protein was found in the serum of any piglet fed either on LL, VS or LC diets. The presence of antibodies against β-conglutin of lupine, vicilin of V. sativa and vicilin of L. cicera , respectively indicated an immune response in weaned piglets. The absence of residual antigenic proteins may be due to the digestive adaptation of the piglet to the legume-based diets. However, no direct relation between the differences in digestibility coefficients among the legume seeds and their antigenicity was established.

Nutrient digestibility of chickpea (Cicer arietinum L.) seeds and effects on the small intestine of weaned piglets

Abstract A study involving three groups of six piglets weaned at 28d of age was conducted to determine the effect of two legume seeds (white versus black chickpea) on total tract (TTAD) and ileal (IAD) apparent digestibility, and their impact on intestinal tissues sampled at slaughter. TTAD was measured between 32 and 39 days of age and IAD was measured between 53 and 60 days on the same piglets anastomosed ileo-rectally. The piglets were fed at a similar DM intake a control diet (C) based on casein or a diet in which 50% of crude protein (CP) was supplied by white (WCP) or black chickpea (BCP). TTAD of dry matter (DM) and energy was lower ( P P P >0.05). The main effects observed on gut morphology with the legume diets were moderate villus atrophy and crypt hyperplasia. Villus height at the ileum was smaller with the BCP diet than with WCP and C ( P P P

The effect of genotype and dietary fibre level on the caecal bacterial enzyme activity of young piglets: digestive consequences

The effect of genotype and dietary fibre level on the coefficient of total tract apparent digestibility (CTTAD) and dry matter (DM), pH, ammonia-nitrogen (N-NH 3 ), short chain fatty acids (SCFA) and microbial enzyme activity, in the caecal contents, of young piglets, was studied using 16 Alentejano (AL) and 16 Duroc x Landrace (D x LD) piglets, aged 35 days. Piglets of each genotype, were distributed in two groups of eight animals housed individually and received on a pair feeding basis, one of the two experimental diets. The diets were formulated to contain 100 or 170 g NDF kg -1 by partial replacement of wheat by wheat bran. The piglets were individually controlled during 4 successive weeks and faeces were collected during the first and the last week for digestibility measurements. At the end of the experimental period, all piglets were slaughtered and the caecal contents collected. The CTTAD of NDF was 0.64 and 0.54 (P < 0.001) and that of ADF was 0.58 and 0.37 (P < 0.001) for AL and D x LD piglets, respectively. Excepting CP and minerals, the increase of the fibre level significantly decreased the CTTAD of dietary constituents. The total xylanolytic activity was 22.0 and 13.6 (mg h -1 g -1 of fresh caecal contents) and the total cellulolytic activity was 24.7 and 12.6 (mg h -1 g -1 of fresh caecal contents) for AL and D x LD piglets, respectively (P < 0.10). The acetic:propionic ratio (C2:C3) was significantly higher in the caecal contents of AL piglets. However in D × LD piglets the proportion of propionic acid (C3) was higher (P < 0.01). The fibre level had no significant effect on total and specific activity of amylase, xylanase, pectinase and cellulase in the caecum. The concentration and profile of SCFA and the level of N-NH 3 in caecal contents was not significantly affected by the dietary fibre level. In conclusion, the higher digestive capacity of AL piglets towards the non-starch polysaccharides seems to be related to a better adaptation of the enzymatic activity i.e. xylanase and cellulase of the caecal microflora to degrade the cell wall constituents of the diet.

Legume Proteins of the Vicilin Family are More Immunogenic Than Those of the Legumin Family in Weaned Piglets

Two experiments were conducted to study the systemic and local immune responses to legume proteins in piglets weaned at 28 d of age. The pigs were fed a control diet (C) based on casein or diets in which 50% of crude protein (CP) was supplied by soya bean meal (SBM), pea (P), faba bean (FB), or lupin (L) seeds in experiment 1, and white chickpea (WCP) or black chickpea (BCP) seeds in experiment 2. Blood samples and intestinal secretions were collected at slaughter four weeks later and analysed for specific antibodies using ELISA and western blotting. Piglets fed the legume-containing diets had higher ( P < 0.10) plasma immunoglobulin (Ig) G ELISA titres to legume proteins than did piglets fed a casein-based diet. Many protein bands in the molecular weight range of 94.0-14.4 kDa were recognized by plasma IgG and IgA antibodies. The most immunogenic bands belonged to proteins of the vicilin family and to other unidentified minor proteins. No specific IgA antibodies were detected in intestinal secretions by ELISA and western blotting.

Component digestibility of lupin (#Lupinus angustifolius#) and pea (#Pisum sativum#) seeds and effects on the small intestine and body organs in anastomosed and intact growing pigs

Thirty-six male growing pigs were used to compare the component digestibility of legume seeds and the impact of diets and ileo-rectal anastomosis (IRA) on the morphology and enzyme activities of intestinal mucosa. The pigs were fed a control (C) diet based on casein or a diet in which 60% of crude protein (CP) was supplied by blue lupin (Lupinus angustifolius) (L) or pea (Pisum sativum) (P) seeds. Coefficient of total tract apparent digestibility (CTTAD) of organic matter (OM), CP and gross energy (GE) was lower in the L diet compared to the control diet. The pea-based diet presented intermediate CTTAD values of OM and GE. Coefficient of ileal apparent digestibility (CIAD) of OM and GE was lower in the legume-containing diets than with C. No significant differences were found for the CIAD of CP. There was a significant interaction between diet and IRA for villus height in the jejunum and crypt width in the ileum. Duodenal and jejunal crypt width was lower in the pigs fed the legume-containing diets compared to controls. The diet influenced the specific activity of most intestinal enzymes at various sites along the small intestine. Anastomosed pigs had higher spleen and small intestine weights and lower large intestine weights as compared to intact pigs. IRA influenced intestinal villus and crypt architecture but it had no significant effect on the activities of intestinal enzymes.

Effect of the source of dietary fat on postweaning lipogenesis in lean and fat pigs

Twenty-four male piglets weaned after 21 days, 12 of the Large White lean breed (LW) and 12 of the Alentejano fat breed (AL), have been used to compare the effects of genotype and source of dietary fat on the activities of enzymes involved in lipogenesis and on the composition of selected fatty tissues. During 4 weeks the piglets were fed isoenergetic and isonitrogenous experimental diets, containing 5% of either olive oil or tallow. In AL piglets the acetylcoenzyme A carboxylase activity was three- and ninefold higher, the malic enzyme activity six- and fivefold, and the glucose-6-phosphate dehydrogenase activity was four- and fivefold higher in the dorsal subcutaneous and in the perirenal fat, respectively, than in LW piglets. In general, fatty tissues of the AL piglets contained a higher proportion of saturated fatty acids. Olive oil induced a significant increase in the activities of malic enzyme and glucose-6-phosphate dehydrogenase in both tissues, but only slightly increased the acetylcoenzyme A carboxylase activity in perirenal fatty tissues (p < 0.05). The fatty acid profile of the subcutaneous and of the perirenal fat was strongly affected by the composition of dietary fat. These observations showed that the source of dietary fat influenced markedly lipid metabolism and body composition since a very early age.

Selection of Pinus pinea L. plus tree candidates for cone production

Abstract• Multivariate statistical analysis was used to define different developmental stages for stone pine (Pinus pinea L.) considering tree size and cone production, without site-specific information.• This was achieved in two steps. First, trees from permanent plots were classified using cluster analysis in five different stages. Second, discriminant analysis was applied to confirm the robustness of the groups generated by cluster analysis and to allow the assignment of new stone pine trees to one of the five development stages. Each development stage was associated with an average cone production.• A methodology for selecting candidates for plus trees was suggested. Trees belonging to the 90th quartile or higher for the number of cones per crop and for cone crop weight were identified throughout the three years of the study.• Trees were evaluated as potential candidates for plus trees using the following variables: the number of cones, cone crop weight and relative production capacity. The relative production capacity was defined as the cone crop weight per square meter of the crown area.