Article

Kanengoni, A. T., Chimonyo, M., Ndimba, B. K. and Dzama, K. (2015) Feed preference,nutrient digestibility and colon volatile fatty acid production in growing SouthAfrican Windsnyer-type indigenous pigs and LargeWhite Landrace crosses fed diets containing ensiled maize cobs Livestock Science 171 (2015) 28–35

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  • Johannesburg City Parks and Zoo
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Abstract

A studywascarriedouttoevaluatefeedpreference,nutrientdigestibilityandcolon fermentationingrowingSouthAfricanWindsnyer-typeIndigenouspigs(SAWIP)andLarge White�Landracecrosses(LW�LR)feddietscontainingensiledmaizecobs.Threetreatments; CON(controldietwithoutmaizecobs),LMC(lowmaizecobleveldiet)andHMC(highmaize cob leveldiet)wereevaluated.Preferencewasassessedin64LW�LR (4576.7kg)and30 SAWIP(2173.6kg)byofferingthepigschoicesbetweenacommonreferencedietandatest diet.Apparenttotaltractdigestibility(ATTD)andcolonfermentationweredeterminedusing15 LW�LR and15SAWIPpigsweighing7076.9kgand4978.1kg,respectively.Therewere breedbydietinteractions(Po0.05)inperiod1(P1;days0–3)forpreferenceofdietsbutnone in period2(P2;days3–6).TheSAWIP’s preferencefortheCONwasgreaterthanfortheHMC diet(Po0.05).Thetwobreeds’ preferencesfortheLMCandHMCdietswerelower(Po0.05) than the50%preferenceindexinP1.TheATTDcoefficientsofcrudeprotein(CP),aciddetergent fibre(ADF),hemicellulose(Hemi)andamylasedeterminedneutraldetergentfibre(αNDF) in theHMCweregreater(Po0.05)thanintheCON.TheSAWIPhadgreater(Po0.05)NDF digestibilitycoefficientsthantheLW�LR.Therewerebreed�dietinteractions(Po0.05)for proportionsofisobutyricacid(IBA)andbutyric acid(BA),IBAconcentrationandaceticto butyricacid(AA:BA)andBA:IBAratios.TheLW�LR hadgreaterconcentrationsoftotalvolatile fattyacids(VFA)(Po0.05)thantheSAWIP.Theresultsprovideabasistopromoteensilingasa waytoimproveutilisationofmaizecobs.Theinfluenceofbreedofpigneedstobeconsidered when formulatingdietscontainingfibrousingredients.

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The availability of xylan-type polysaccharides, representing an immense resource of biopolymers for practical application, is summarized. Xylans constitute 25-35% of the dry biomass of woody tissues of dicots and lignified tissues of monocots and occur up to 50% in some tissues of cereal grains. The most potential sources of xylans include many agricultural crops such as straw, sorghum, sugar cane, corn stalks and cobs, hulls and husks from starch production, as well as forest and pulping waste products from hardwoods, in particular. The structural diversity and complexity of xylans is illustrated and shown to depend on the botanic source. Various extraction procedures suitable for the isolation of xylans from different plant sources are described and compared. It is suggested that certain structural types of xylans like glucuronoxylan, arabinoglucuronoxylan, and arabinoxylan can be prepared from certain plant sources with similar chemical and physical properties. In contrast to structural analyses, the physicochemical properties, including solubility, molecular weight and molecular weight distribution, and rheological properties have been studied only for few xylan types. From the functional properties, the thermophysical and tensioactive properties are described. Finally, the physiological activities of xylans, which represent important dietary fibers as well as the immunological activities of some xylan types, are presented.
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Data from pigs between 12 and 120 kg live weight were used to develop a relationship between the capacity for food bulk and live weight. High bulk foods, intended to limit growth, were offered for 21 days to pigs of 12, 36 (600 g sugar-beet pulp per kg (SBP60)) and 108 (800 g sugar-beet pulp per kg (SBP80)) kg live weight. Control pigs were given a low bulk food C at all weights. After 21 days the pigs were slaughtered and measurements made on the gastro-intestinal tract (GIT). In two additional treatment groups SBP60 was offered from a weight of either 36 kg or 72 kg before SBP80 was offered at 108 kg. Daily live-weight gain, after allowing for the effects of a change of gut fill, was less at all weights on the high bulk foods than on C. At all weights the high bulk foods caused a significant increase in the weights of the stomach, large intestine, caecum and gut fill. Effects on the weight of the small intestine were small. Previous nutrition had no significant effect on the adapted performance, or on the size of the GIT, of pigs given SBP80 at 108 kg but pre-feeding SBP60 significantly increased initial consumption of SBP80. Constrained intake was not directly proportional to live weight beyond 40 kg. The absolute capacity for bulk (Cap, kg water-holding capacity per day) was related to live weight (W, kg) by the quadratic function Cap = (0.192.W) - (0.000299.W2). The value of Cap is predicted to reach a maximum when W = 321 kg. The combined weights of the large intestine and caecum (WLIC) changed with W in ways that were similar to the way in which Cap changed. In addition the ratio of Cap to WLIC was close to constant. The combined weight of the large intestine and the caecum may determine the capacity for food bulk in pigs.
Article
The aim of this work was to evaluate the influence of a coarse ground cereal and two fibrous ingredients incorporated in the diet on the physicochemical properties of digesta and productive parameters of pigs during the first stage of the growing period. A total of 96 pigs (initial body weight, BW, 15 kg) were distributed into four experimental treatments: the control diet (CT) consisted of corn, barley and soybean meal milled to pass through a 2.5 mm screen; the coarse corn diet (CC) was prepared by milling the corn to a coarser particle size (4.0 mm screen); the sugar beet pulp diet (SBP) and the wheat bran diet (WB) were prepared by replacing some of the corn for sugar beet pulp (80 g/kg) or wheat bran (100 g/kg) respectively, in order to contain a higher amount of non-starch polysaccharides (NSP). Three experimental periods were considered (7, 21 and 42 days) during which body weight (BW) and voluntary feed intake were assessed. At the end of each period eight animals per diet were slaughtered. Weight of the gastrointestinal tract and its compartments (full and empty) was recorded and the contents were sampled. Digesta samples were analysed for water concentration, water retention capacity (WRC), ammonia and short-chain fatty acids concentration (SCFA). Histological study of the proximal colon tissues was also performed. In general, the different parameters evaluated showed differences between the experimental periods, but few interactions were recorded. Animals fed CC, SBP and WB diets presented a lower feed intake (P≤0.009) compared to CT fed animals. Compared to the control diet, coarse grinding of corn provoked an increase in the colonic digesta content (P=0.032). Similarly, animals fed the SBP diet compared to CT animals, showed an increase in the contents (P=0.009) of hindgut, and in the concentration of water in the digesta (P≤0.011). Compared to CT diet the SBP diet lowered the ammonia concentration in the hindgut contents (P≤0.045) and increased the concentration of SCFA in the distal colon (P≤0.025). Animals fed the SBP diet also showed a lower number of lymphoid nodes in the colonic mucosa compared to the other diets (P≤0.043). Minor modifications were observed associated with the incorporation of wheat bran in the diet, but colonic water from WB fed animals showed a tendency to increase cytolytic capacity. The results confirm major changes in the voluntary intake and physicochemical properties of digesta as affected by the incorporation in the diet of a fibrous ingredient or coarse grinding of cereals.
Article
A comparative study was performed to determine the digestibility and performance in Zimbabwean indigenous Mukota pigs and exotic Large White pigs fed high fibre diets. Maize cob meal was used as the source of dietary fibre at levels of 0, 100, 200 and 300g/kg. In the digestibility experiment (Experiment 1), four male pigs from each breed were used in a Latin square design. In the feeding trial (Experiment 2), 16 male pigs from each of the two breeds were used in a 2×4 factorial. Polynomial regression analysis was used to determine the relationship between maize cob levels with digestibility of nutrients, feed intake, average daily gain (ADG) and feed conversion ratio (FCR). In Experiment 1, increasing fibre levels in the diets resulted in a linear decrease (P0.05) of maize cob level on feed intake for both Large White and Mukota pigs. The decrease in ADG in the Large White was linear (β=0.0043; R2=0.976) and quadratic in the Mukota pigs (P
Article
Data collected from several studies including unpublished data, carried out since 1988 at the University of Bologna, on the incorporation of pressed beet pulp silage (PBPS) in the diet of heavy pigs (160kg live weight (LW)) have been analysed collectively. Large amounts of PBPS (0.5 of dry matter (DM) intake) in the diet were well tolerated by pigs (ranging in LW from 34 to 144kg) and were associated with a marked reduction of gastric lesions. When used in practical diets from 44 to 153kg LW at 170gkg−1 DM basis, PBPS did not modify either growing parameters or slaughtering performances of heavy pigs in comparison with animals receiving a concentrated diet mainly based on cereals and soyabean meal. The use of PBPS did not modify the weight losses of hams (Parma ham) during their seasoning process, lasting more than 12 months for this typical product. Similarly, the fatty acid composition of cured ham fat was not influenced by the dietary inclusion of beet pulp. When replacing barley (150gkg−1 DM basis), both plain or molassed PBPS did not modify slaughtering parameters of heavy pigs and fatty acid composition of hams. Plain PBPS resulted in a significant (P
Article
The aim of this study was to determine the effect of applying a bacterial inoculant with enzymes to D. eriantha on the fermentation dynamics during ensiling, the aerobic stability, intake and digestibility of the silage. The grass was ensiled, with or without the addition of a lactic acid bacterial inoculant at 106colony forming units per gram of fresh material, in Cryovac barrier bags. The inoculant Sil-All (Supplied by Alltech Biotechnology) contained Lactobacillus plantarum, Steptococcus faecium and Pediococcus acidilactici together with the enzymes, cellulase, hemicellulase and amylase. To follow the fermentation dynamics during ensiling samples were taken on days 1, 2, 5, 9 and 44 of ensiling for chemical and microbiological analysis. The inoculant resulted in a more rapid drop in pH, a higher level of lactic acid and lactic acid bacteria, less protein breakdown and lower numbers of enterobacteria, clostridial spores, yeast and mould compared to control silage. Silage was made on a larger scale in two tower silos (1.5t silage capacity) for each of the control and inoculated treatment. D. eriantha hay was also made at the same time. Silage and hay diets were fed to 24 Merino rams (n=8 per treatment), weighing 62±2.7kg to determine intake and digestibility. The intake of diets consisting of 90.9% D. eriantha hay, control silage or inoculated silage, differed significantly (p
Article
A spectrophotometric procedure was developed using ashing at 450 °C followed by acid digestion in beakers and reading the diluted digests at 440 nm. Errors were minimized by use of blanks and maintenance of a constant acid concentration in the diluted digests.
Article
The objective of the present study was to predict scaled feed intake (SFI) using the physico-chemical measurements of feed bulk, such that gut capacity can be estimated in weaner pigs. A basal feed with 13·7 MJ digestible energy and 180 g crude protein per kg DM was diluted to six inclusion levels (0, 80, 160, 240, 320 and 400 g/kg DM) using lucerne hay, maize cob, maize stover, sawdust, sunflower husks or grass hay (veld grass). A total of 124 pigs weighing 18·1 (sd 1·37) kg body weight were used. Water-holding capacity (WHC; g water/g DM), bulk density (g DM/ml), neutral-detergent fibre (NDF) and acid-detergent fibre (ADF) influenced the SFI. The quadratic relationship between SFI and WHC was SFI = 19·1 (sem 3·49)+10·04 (sem 1·61) WHC-1·11 (sem 0·17) WHC2 (P< 0·01). SFI was also related (P< 0·01) to NDF and ADF by quadratic functions SFI = 24·3 (sem 3·55)+0·12 (sem 0·229) NDF - 0·00 012 (sem 0·000036) NDF2 and SFI = 30·2 (sem 1·95)+0·112 (sem 0·0232) ADF-0·000343 (sem 0·0000612) ADF2, respectively. Using broken-stick analyses, the gut capacity was attained when WHC = 4·53 (sem 1·25) g water/g DM, NDF = 367 (sem 29) g/kg DM and ADF = 138 (sem 77) g/kg DM. In conclusion, although threshold values for each were different, WHC, NDF and ADF contents of bulk feeds provide relationships with SFI that can be used to predict gut capacity in weaner pigs.
Article
A gas-liquid chromatography method for simultaneous determination of volatile fatty acids and lactic acid was improved by the use of a new packing material, poly(ethylene glycol phthalic acid ester) coated on a solid terephthalic acid support. The method appears to be accurate, simple, and quick enough for routine silage analysis.
Article
BACKGROUND: We recently determined that 150 g kg−1 of lucerne meal can be fed during the finishing period without detrimental effects on pig performance but lucerne should be limited to less than 75 g kg−1 during the growing period. Lucerne has a high fiber content, is poorly digested and contains antinutritional factors such as saponins which reduce palatability. Therefore, pig performance could be enhanced by supplementing lucerne-containing diets with feed additives such as flavors, enzymes or organic acids. The objective of this study was to determine the effects of these additives on nutrient digestibility, performance and carcass traits when fed to growing-finishing swine fed diets containing lucerne. RESULTS: Flavor and enzyme had no effect on nutrient digestibility, pig performance or carcass traits. During the growing period, inclusion of propionic and acetic acids increased (P < 0.05) the digestibility of dry matter, protein and energy. Weight gain and intake also increased (P < 0.05). None of the additives had any effect on pig performance during the finishing period or on carcass traits. CONCLUSION: During the growing period, including 200 g kg−1 lucerne was detrimental to pig performance. Addition of organic acid improved pig performance and nutrient digestibility. During the finishing period, 200 g kg−1 lucerne can be successfully incorporated into pig diets without negative effects on pig performance. Copyright
Article
Four experiments were conducted to evaluate the palatability of sorghum, maize, rye and lupine for pigs. Diets containing sorghum, maize, rye or lupine (test diets) were offered in a series of double choice tests against a reference diet. To prepare the reference diets, white broken rice in the experiments with cereals, and SBM-56 (a soy protein product low in anti-nutritional factors) in the experiment with lupine, were used as the cereal and the protein source of reference, respectively. Six test diets containing sorghum, maize or rye were prepared by replacing either 250 or 500 g kg − 1 of broken rice from the reference diet. Similarly, two test diets containing lupine were prepared by replacing 75 or 150 g kg − 1 of SBM-56 from the reference diet. Additionally, the pure ingredients were also evaluated against pure broken rice (sorghum, maize or rye) and pure SBM-56 (lupine). In each experiment, the corresponding ingredient was tested at two levels of inclusion and in pure form, using both newly weaned pigs and pigs at four weeks post-weaning. The palatability for each test diet expressed as % of preference was calculated as the percentage contribution of the test diet to total feed intake (test + reference diets). The preferences obtained ranged between 16 and 29% for sorghum, 16 and 35% for maize and 19 and 49% for rye. Except for rye at 500 g kg − 1 (49%), preference values were significantly different from 50% which indicates a higher preference for the broken rice in the reference diet than for sorghum, maize and rye. Preference for lupine ranged between 39 and 56% and no difference in preference was observed between the lupine in the test diets and the SBM-56 in the reference diets. The dietary preferences could already be observed in the first days of experiment, and they did not change substantially thereafter. The levels of inclusion tested did not have an effect on preference for any of the ingredients. The age of the animals did not affect preference and the values obtained in newly weaned and post-weaned pigs were generally in good agreement. However the use of the older animals resulted in higher feed intakes and more accurate measurements. It is concluded that feedstuff palatability can be quantified with a double choice protocol using a reference diet. This should allow the formulation of feeds for weaning pigs taking into account the palatability of the ingredients, in addition to other nutritional criteria. Preference evaluation may become a useful tool to improve the palatability of the diets and facilitate piglets feed initiation at weaning.
Article
The availability of xylan-type polysaccharides, representing an immense resource of biopolymers for practical application, is summarized. Xylans constitute 25–35% of the dry biomass of woody tissues of dicots and lignified tissues of monocots and occur up to 50% in some tissues of cereal grains. The most potential sources of xylans include many agricultural crops such as straw, sorghum, sugar cane, corn stalks and cobs, hulls and husks from starch production, as well as forest and pulping waste products from hardwoods, in particular. The structural diversity and complexity of xylans is illustrated and shown to depend on the botanic source. Various extraction procedures suitable for the isolation of xylans from different plant sources are described and compared. It is suggested that certain structural types of xylans like glucuronoxylan, arabinoglucuronoxylan, and arabinoxylan can be prepared from certain plant sources with similar chemical and physical properties. In contrast to structural analyses, the physicochemical properties, including solubility, molecular weight and molecular weight distribution, and rheological properties have been studied only for few xylan types. From the functional properties, the thermophysical and tensioactive properties are described. Finally, the physiological activities of xylans, which represent important dietary fibers as well as the immunological activities of some xylan types, are presented.
Article
Milled corncobs were treated with hot, compressed water under a variety of operational conditions to cause the hydrolytic degradation of arabinoxylan. Hemicellulose-derived products (substituted oligosaccharides and monosaccharides) and non-saccharide compounds were found in the reaction media. Liquors obtained in hydrothermal treatments carried out under optimal conditions were concentrated and subjected to crossflow ethyl acetate extraction (three stages) and ionic exchange (with Amberlite IRA 400 or Amberlite IRA 96) to decrease the content of non-saccharide components. The various streams involved in the whole process were assayed for composition, and material balances were formulated for the best situation. The highest purification degree corresponded to operation with Amberlite IRA-400, which led to a final isolate (made up of monosaccharides, substituted oligosaccharides and nonvolatile, non-saccharide components) containing 88.7 weight percent of saccharides and 11.3 weight percent of non-saccharide components (mainly made up of phenolic substituents and melanoidins). The recovery of soluble oligosaccharides accounted from 23.3 weight percent of the raw material, whereas the yield in substituted xylooligosaccharides reached 45.5% of the amount corresponding to the stoichiometric conversion of the polymeric components contained in the raw material.
Article
There is a need to standardize the NDF procedure. Procedures have varied because of the use of different amylases in attempts to remove starch interference. The original Bacillus subtilis enzyme Type IIIA (XIA) no longer is available and has been replaced by a less effective enzyme. For fiber work, a new enzyme has received AOAC approval and is rapidly displacing other amylases in analytical work. This enzyme is available from Sigma (Number A3306; Sigma Chemical Co., St. Louis, MO). The original publications for NDF and ADF (43, 53) and the Agricultural Handbook 379 (14) are obsolete and of historical interest only. Up to date procedures should be followed. Triethylene glycol has replaced 2-ethoxyethanol because of reported toxicity. Considerable development in regard to fiber methods has occurred over the past 5 yr because of a redefinition of dietary fiber for man and monogastric animals that includes lignin and all polysaccharides resistant to mammalian digestive enzymes. In addition to NDF, new improved methods for total dietary fiber and nonstarch polysaccharides including pectin and beta-glucans now are available. The latter are also of interest in rumen fermentation. Unlike starch, their fermentations are like that of cellulose but faster and yield no lactic acid. Physical and biological properties of carbohydrate fractions are more important than their intrinsic composition.
Article
The effects of the amount and the type of dietary fibre on the apparent digestibility (AD) by growing pigs of neutral-detergent fibre (NDF) and NDF components, on nitrogen balance and on the rate of passage of digesta were studied using a semi-purified basal diet and fibre in the forms of soya-bean hulls, lupin (Lupinus sp.) hulls, pea (Pisum sativum) hulls, wheat bran, maize hulls, maize cobs, oat hulls and lucerne (Medicago sativa) stems. Both the amount and the type of dietary fibre significantly influenced the AD of dietary dry matter, N and energy. The AD of NDF and of NDF components was markedly affected by the type and the amount of fibre in the diet. The proportion of NDF digested ranged from 0.016 to 0.905, of cellulose from 0.026 to 0.931 and of hemicellulose from 0.010 to 0.999. N retention by the pigs ranged from 12.9 to 25.8 g/d and with some fibres there was a tendency towards increased N retention with increasing intakes of NDF. Rate of passage of digesta, expressed as the 50 and 95% excretion times of stained feed particles, ranged from 22.2 to 85.1 h and 40.0 to 117.1 h respectively. Large individual variations in rate of passage occurred but, in general, the rate of passage tended to increase with increasing intakes of NDF. No strong associations between the rate of passage of digesta and apparent digestibility of NDF components were observed. The results suggest that the extent of fibre digestibility depends predominantly on the origin of the fibre and to a lesser extent on the amount of fibre in the diet.
Article
The standard method described by Barker and Summerson for measuring lactic acid concentration has been modified to give a simpler and more rapid procedure, which is applicable to plasma or other biological fluids, and is more convenient for routine laboratory analyses.
Article
Suspensions of isolated epithelial cells (colonocytes) from the human colon were used to assess utilisation of respiratory fuels which are normally available to the colonic mucosa in vivo. Cells were prepared from operative specimens of the ascending colon (seven) and descending colon (seven). The fuels that were used were the short chain fatty acid n-butyrate, produced only by anaerobic bacteria in the colonic lumen, together with glucose and glutamine, normally present in the circulation. The percentage oxygen consumption attributable to n-butyrate, when this was the only substrate, was 73% in the ascending colon and 75% in the descending colon. In the presence of 10 mM glucose these proportions changed to 59% and 72%. Aerobic glycolysis was observed in both the ascending and descending colon. Glucose oxidation accounted for 85% of the oxygen consumption in the ascending colon and 30% in the descending colon. In the presence of 10 mM n-butyrate these proportions decreased to 41% in the ascending colon and 16% in the descending colon. Based on the assumption that events in the isolated colonocytes reflect utilization of fuels in vivo, the hypothesis is put forward that fatty acids of anaerobic bacteria are a major source of energy for the colonic mucosa, particularly of the distal colon.
Article
Short-chain fatty acid (SCFA) formation by intestinal bacteria is regulated by many different host, environmental, dietary and microbiological factors. In broad terms, however, substrate availability, bacterial species composition of the microbiota and intestinal transit time largely determine the amounts and types of SCFA that are produced in healthy individuals. The majority of SCFA in the gut are derived from bacterial breakdown of complex carbohydrates, especially in the proximal bowel, but digestion of proteins and peptides makes an increasing contribution to SCFA production as food residues pass through the bowel. Bacterial hydrogen metabolism also affects the way in which SCFA are made. This outcome can be seen through the effects of inorganic electron acceptors (nitrate, sulfate) on fermentation processes, where they facilitate the formation of more oxidised SCFA such as acetate, at the expense of more reduced fatty acids, such as butyrate. Chemostat studies using pure cultures of saccharolytic gut micro-organisms demonstrate that C availability and growth rate strongly affect the outcome of fermentation. For example, acetate and formate are the major bifidobacterial fermentation products formed during growth under C limitation, whereas acetate and lactate are produced when carbohydrate is in excess. Lactate is also used as an electron sink in Clostridium perfringens and, to a lesser extent, in Bacteroides fragilis. In the latter organism acetate and succinate are the major fermentation products when substrate is abundant, whereas succinate is decarboxylated to produce propionate when C and energy sources are limiting.
Nutrient Requirements of Swine
NRC, 1998. Nutrient Requirements of Swine, 10th ed. National Academy Press, Washington, D.C.
The effect of varying dietary levels of maize cob meal on the growth and nutrient digestibility of grower pigs
  • E C Ndubuisi
  • F C Iheukwumere
  • M U Onyekwere
Ndubuisi, E.C., Iheukwumere, F.C., Onyekwere, M.U., 2008. The effect of varying dietary levels of maize cob meal on the growth and nutrient digestibility of grower pigs. Res. J. Anim. Sci. 2, 100-102.
Association of Official Analytical Chemists
AOAC, 1997. Official Methods of Analysis, 15th ed. Association of Official Analytical Chemists, Washington DC, USA.