The nutritional value for sheep of molasses and condensed molasses solubles

The nutritional value of cane molasses and condensed molasses solubles (CMS, a highnitrogen by-product from the fermentation of beet molasses) was studied in two metabolism experiments with sheep.Nitrogen balance and the apparent digestibility of dry matter, organic matter, ether extract and acid detergent fibre in a barley-based control diet were not affected when 10 or 20% barley dry matter was replaced by either molasses or CMS dry matter. The digestibility of crude protein was significantly increased by CMS, because it increased the crude protein content of the rations. There was a positive linear relationship between crude protein and digestible protein as a percentage of the dry matter. The digestibility of nitrogen-free extract was depressed by the inclusion of molasses or CMS. Digestibility of energy was not significantly influenced by the inclusion of molasses at 10 or 20% or CMS at 10% but was depressed by the inclusion of CMS at 20%. The digestible energy of molasses was 82% of that of barley and the digestible energy of CMS was 84% of that of molasses.The extent of fermentation of ration components was studied in sheep with rumen and duodenal re-entrant cannulae. Although the apparent digestibility of dry matter, organic matter and gross energy was not affected by 20% molasses or CMS, the concentration of butyric acid in the rumen liquor was significantly increased at the expense of propionic acid. The concentration of ammonia in the rumen was elevated by high nitrogen intake. High concentrations of ammonia in the rumen liquor caused proportional excretion of nitrogen in urine.     

Intake and digestion by lambs of dwarf elephant grass (Pennisetum purpureum Schum. cv. Mott) hay or hay supplemented with urea and different levels of cracked corn grain

This study was carried out to evaluate intake, digestibility, ruminal fermentation, nitrogen (N) retention and ruminal microbial protein synthesis in lambs fed dwarf elephant grass (Pennisetum purpureum Schum. cv. Mott) hay or hay supplemented with urea and 0, 5, 10 or 15 g/kg of live weight (LW) of cracked corn grain. Ten lambs (mean LW of 28 ± 0.9 kg), housed in metabolic cages, were used in a double 5 × 5 Latin Square experiment. Except fibre intake and digestibility, which was higher, the intake and digestibility of the others feed components, as well as ruminal microbial protein synthesis and N retention were lower in non-supplemented lambs. Corn supplementation increased total dry matter (DM) (P<0.05), organic matter (OM), non-structural carbohydrate (NSC) and energy intake (P<0.01) but decreased total neutral detergent fibre (aNDFom) (P<0.01) intake, as well as OM and aNDFom intake from the hay (P<0.01). Apparent DM, OM and energy digestibility, as well as OM true digestibility (OMTD) increased (P<0.01), and aNDFom digestibility decreased linearly (P<0.01) as corn supplementation increased. Total N intake was not influenced but, apparent and true N digestibility, as well as urinary N excretion decreased (P<0.01), and ruminal microbial N entering the small intestine increased linearly (P<0.01) as corn supplementation increased. However, the efficiency of ruminal microbial protein synthesis was similar for all treatments. Mean ruminal pH values and ammonia N concentrations decreased linearly (P<0.01) with level of corn supplementation. Ammonia N and amino acid, as well as peptide concentrations in ruminal fluid were quadratically related (P<0.01) with the time after feeding. Corn supplementation had a linear additive effect on total dry matter and digestible energy intake, as well as on N retention, but a linear negative effect on hay intake and on fibre digestibility. However, decreased forage digestibility by animals was probably neither related to lower ruminal pH, which values were always higher than 7.0, nor related to ruminal sugar concentrations, which were similar for all treatments.     

Chemical composition,digestibility and feeding value of maize cobs

The digestibility of treated maize cobs was studied using Romney Marsh wether sheep in a 2 × 3 factorial design; maize cobs were ground through a 10- or 6-mm screen and three chemical treatments were applied to each grinding: distilled water (control); sodium hydroxide (4.5 g per 100 g cob dry matter); and Magadi soda (9.0 g per 100 g cob dry matter). Cobs were treated for 24 h using one litre of solution per kg of maize cobs.The digestion coefficient of crude protein was lowered (P< 0.01) by finer grinding of the maize cobs. Dry matter digestibility coefficients were 44.7, 54.2 and 61.6% for maize cobs treated with water, NaOH and Magadi soda, respectively. Digestibility of energy, cell walls and cellulose was increased more by Magadi soda than by NaOH. Digestibility of acid detergent fibre (ADF) was depressed (P< 0.05) by NaOH but improved (P< 0.05) by Magadi soda. Chemical treatment lowered (P< 0.01) the digestibility of crude protein from 28.0 to 17.0% (NaOH) or to 18.7% (Magadi soda). Grinding and chemical treatment of maize cobs interacted (P< 0.01) in their effects on digestibility of crude protein.Friesian cattle, grazed on a predominantly Nandi Setaria (Setaria sphacelata) and Silver Leaf Desmodium (Desmodium uncinatum) pasture, and supplemented with water-, NaOH- and Magadi soda-treated maize cobs, gained 0.41, 0.55 and 0.51 kg per day, respectively. Daily maize cob intake was higher on NaOH-treated than on water- and Magadi soda-treated cobs. Cattle on NaOH- and Magadi soda-treated cobs required more than 1 month to adapt to the cobs and show superior gain.     

Evidence of genetic variability for digestive efficiency in the growing pig fed a fibrous diet

Energy digestibility in the growing pig increases with BW increase and may differ between breeds of pigs or between lines selected on criteria other than digestion. However, little is known about the variability in energy digestibility within a line or a breed of pigs, especially when fibrous diets are fed. For this purpose, 20 Large White castrated male growing pigs originating from four boars (five per boar), and three to four sows per boar, were fed a high dietary fibre (DF) diet (18% NDF) and measured over 10 consecutive weeks (30 to 95 kg BW range) for their apparent faecal energy, nitrogen and organic matter digestibility. Each week, faeces were totally collected over 5 days and the feed dry matter intake over the same days was recorded. All digestibility coefficients increased regularly (P < 0.001) over the experimental periods or with BW increase (+0.6 point/10 kg BW increase for energy); this rate of increase was not affected by boar origin (no interaction; P > 0.05). The digestibility coefficients were affected by boar origin (P < 0.005 for energy), with about 2 points for energy between the extremes (81.7% v. 79.5%), and there was no marked interaction between boar origin and period. These preliminary results suggest the possibility of selecting growing pigs for an increased digestive efficiency when fed high DF diets.     

Nutritive value of thermoammoniated and steam-treated maize stover. I. Intake,digestibility and nitrogen retention

Chopped maize stover, ammoniated at ambient and elevated temperatures or steamed, was evaluated with eight wether lambs in a 4 × 4 double Latin square design. Treatments were: (i) control, 60% H₂O, ensiled for at least 40 days; (ii) 3% NH₃, 60% H₂O for 30 days at 21°C; (iii) 3% NH₃, 60% H₂O for 12 h at 90°C; (iv) steamed at 16.2 kg/cm² and 213°C for 4 min. Ammoniated materials were aerated prior to feeding. All rations were equally supplemented with molasses and soya bean meal while urea was added to treatments (i) and (iv) to increase the crude protein content to at least 12%. Ammoniation at ambient and elevated temperatures increased (P < 0.05) organic matter intake by 30 and 39%, respectively. No difference in intake occurred between the control and steam-treated stovers. However, apparent digestibility of dry matter, organic matter, neutral detergent fibre, acid detergent fibre and cellulose increased (P < 0.05) with all treated stovers. Thermoammoniation produced the greatest (P < 0.05) improvements in digestibility. Improvements in nitrogen retention were slight and non-significant with ammoniated stovers.Thermoammoniation of maize stover with 3% NH₃ and 60% H₂O for 12 h at 90°C increased the extent of digestion over ambient ammoniation and steam treatment, and is a rapid and effective method of improving the feeding value of low quality roughages.     

Effects of fibre-degrading enzymes in combination with different fibre sources on ileal and total tract nutrient digestibility and fermentation products in pigs

ABSTRACT

The study was conducted to determine effects of a complex of fibre-degrading enzymes (xylanase, cellulase and β-glucanase) on nutrient digestibility, fibre fermentation and concentrations of short chain fatty acids (SCFA) at different parts of digestive tract in pigs fed different fibre-rich ingredients. A total of 36 barrows fitted with T-cannulas in the distal ileum (initial body weight of 41.1 ± 2.7 kg) were randomly allotted to six dietary treatments with three different high-fibre diets including maize bran (MB), sugar beet pulp (SBP) and soybean hulls (SH) with or without supplementation of fibre-degrading enzymes. Enzyme supplementation improved (p < 0.05) apparent ileal digestibility (AID) of dietary gross energy (GE), crude protein, dry matter (DM), organic matter (OM), total dietary fibre (TDF), neutral detergent fibre (NDF) and apparent total tract digestibility (ATTD) of dietary GE, DM, OM, TDF, insoluble dietary fibre (IDF) when pigs were fed MB, SBP or SH diets. When compared to the SBP and SH diets, the AID of GE, DM, ash, OM and NDF in diet MB was higher (p < 0.05), but the hindgut disappearance and ATTD of nutrients, except for ether extract and crude ash, were lower (p < 0.05). Enzyme supplementation increased acetate and total SCFA concentrations in ileal digesta and faeces of pigs. In conclusion, enzyme addition improved IDF fermentation and SCFA concentration in the whole intestine of pigs, and there was a large variation of digestibility of fibre components among MB, SH and SBP owing to their different fibre composition. Therefore, fibre-degrading enzymes should be applied to fibrous diets to improve efficient production of swine, especially considering low fibre digestibility of fibre-rich ingredients.     

Yield,composition and nutritive value of a leaf protein concentrate obtained by fractionating the shelled aerial part of Pisum sativum L.

A leaf protein concentrate (LPC) extracted from shelled plants of pea (Pisum sativum L.) yielded 108 kg DM ha^?1. Dry matter (DM) was analysed for ether extract (13.59%), neutral detergent fibre (NDF, 1.79%), acid detergent fibre (ADF, 0.81%) and total ash (10.57%). The main nitrogen fraction was represented by protein-N (92% of total N). Mineral composition showed an adequate ratio of Ca to P (3). Lysine was present in nutritionally suitable amounts (7.42 g per 100 g recovered amino acids), but methionine was not (1.78). Apparent digestibility (AD; 75.5), true digestibility (TD; 87.6), biological value (BV; 68.8) and net protein utilisation (NPU; 59.7) were determined with Wistar albino rats. Methionine addition improved AD (81.3), BV (80.6) and NPU (70.5), although not TD (87.5) which was already very high.     

The effects of sulphur supplementation on cellulose digestion in vitro and on nutrient digestion,nitrogen metabolism and rumen characteristics of lambs fed on good quality fescue and tropical star grass hays

Experiments were conducted in vitro and in vivo to determine the effects of sulphur (S) supplementation of a good quality fescue hay containing 0.27% total S and a tropical star grass hay containing 0.20% total S. Addition of S was on an isosulphurous basis of either sodium sulphate or D,L-methionine. Cellulose digestion in vitro was improved (P < 0.001) by the addition of 1% urea. Supplementation of forage with 0.05, 0.10 or 0.15% S from either sodium sulphate or methionine also stimulated cellulose digestion in vitro. There were no differences between S sources. The addition of 0.4 or 0.8% nitrate-nitrogen (nitrate-N) (potassium nitrate) depressed (P < 0.05) cellulose digestion in vitro of both hays. No effect of animal adaptation to nitrate was evident. Addition of S partially counteracted the depression in cellulose digestion due to nitrate. Trials were conducted in vivo in which 12 crossbred wether lambs (fescue experiment) or 12 crossbred intact male lambs (star grass experiment) were randomly assigned to one of three treatments: control (forage with no addition of S); forage plus 0.15% S as sodium sulphate; and forage plus 0.15% S as D,L-methionine. Lambs were housed in metabolism crates and each experiment was replicated twice. Dry matter intakes were highest for methionine-supplemented fescue and for S-supplemented star grass, regardless of S source. Dry matter digestibility tended to increase with S addition (fescue experiment) and was significantly higher for S-supplemented star grass. There was a significant increase (P < 0.05) in neutral detergent fibre (NDF) and acid detergent fibre (ADF) digestibility due to supplemental S, regardless of S source. Nitrogen retention, ammonia-N and ruminal volatile fatty acids were unaffected by S supplementation.     

The effect of replacing rice straw with dry wormwood (Artemisia sp.) on intake,digestibility, nitrogen balance and ruminal fermentation characteristics in sheep

This study examined the effect of substituting dry wormwood (Artemisia sp.) for rice straw in sheep diets on intake and apparent digestibility in vivo, nitrogen (N) balance and ruminal fermentation characteristics. Four Corriedale×Polwarth sheep (51.7 ± 1.3 kg) were individually housed in metabolism cages and fed diets (ad. libitum) with a 70:30 forage to concentrate ratio (DM basis), in which the basal rice straw was substituted with 0 (Control), 30 (LW), 50 (MW) or 100 (HW) g/kg of dry wormwood. The experimental design was a 4×4 latin square design in which 10 days of dietary adaptation was followed by 6 days of total feces and urine collection in each period. Rumen fluid was collected from a stomach tube at −0.5, 0.5, 1, 2, 4, and 8 h after the morning feed on day 6 of each collection period and analyzed for volatile fatty acids (VFA). The intakes of dry matter (DM), organic matter intake (OM), crude protein (CP), ether extract (EE), neutral detergent fibre (NDF) and acid detergent fibre (ADF) were higher (P<0.05) in sheep fed diets containing wormwood, than those fed the Control diet. Compared to the Control diet, CP digestibility was higher (P<0.05) in sheep fed MW and N intake, retained N, EE digestibility, urinary purine derivatives and microbial N yield were higher (P<0.05) in sheep fed diets, containing wormwood. Rumen pH was unaffected by treatment. Rumen NH₃-N and VFA concentrations were similar across treatments except that most values for diets containing wormwood were higher (P<0.05) than those for the control diet within the first 2 h of feeding. The non-glucogenic acid ratio was also similar across Control, LW and MW treatments, but it was generally lower in MW versus the Control treatment. In conclusion, substituting wormwood for rice straw in the sheep diets increased feed intake, rumen fermentation, in vivo digestibility, N retention and microbial N yield, particularly at the medium and high levels of wormwood inclusion.     

Effect of high fibre diets formulated with different fibrous ingredients on performance,nutrient digestibility and faecal microbiota of weaned piglets

The aim of the experiment on 180 weaned piglets (8.9 kg body weight) was to investigate the influence of high fibre diets formulated with different fibrous ingredients on performance, nutrient digestibility, diarrhoea incidence and numbers of faecal microbiota. The dietary treatments included a Control diet and five high fibre diets formulated with different fibre sources including wheat bran, soybean hulls, naked oat hulls, palm kernel expeller and bamboo fibre. The high fibre diets averaged 14.6% neutral detergent fibre with different non-starch polysaccharides (NSP) components and were fed ad libitum for 28 d. Faecal samples were collected during the last 3 d of the experiment and the apparent total tract digestibility of nutrients and fibre components were determined. Pigs fed the Control and wheat bran diets had a higher (p ≤ 0.05) average daily gain (ADG) than pigs fed the palm kernel expeller and bamboo meal diets. The reduced ADG for pigs appeared to be related to reductions in the digestibility of gross energy and dry matter, respectively. The feed-to-gain ratio was significantly higher (p ≤ 0.05) for pigs fed the fibre diets. The digestibility of NSP components was different among the treatments. The diarrhoea incidence was not affected by treatments. The abundance of faecal bifidobacteria was significantly higher (p ≤ 0.05) for pigs fed the wheat bran diet than for pigs fed the bamboo meal diet. It was concluded that the diets formulated with different fibre sources when fed to weaned piglets have different effects on pig performance, nutrient digestibility and numbers of faecal microbiota. The wheat bran diet rich in arabinoxylans enabled a better performance than the other tested diets with fibre addition.     

In vitro studies and short-term feeding trial in lambs to evaluate plantain sheath (Musa sapientum) as a feed for ruminants

Plantain sheath (Musa sapientum) contained 6.4% dry matter and 3.4% crude protein, 31.4% crude fibre, 34.6% cellulose, 15.5% hemicellulose and 6% lignin in dry matter.

Digestibility in vitro studies with fistulated bucks revealed a dry matter disappearance of 53.3% after 24 h incubation. The digestibility of neutral detergent fibre (NDF), acid detergent fibre (ADF) and cellulose after 24 h fermentation was 32.2, 21.5 and 30.3%, respectively. After 48 h fermentation, the dry matter digestibility increased to 63.4%, NDF to 47.0%, ADF to 32.2% and cellulose to 42.3%.

A 45-day feeding trial was conducted with 16 crossbred lambs. Plantain sheath replaced paragrass hay dry matter at 32.6, 54.7 and 76.6% levels. Dried plantain sheath, which contributed 14.1, 25 and 34.5% of total dry matter intake, helped a daily gain of 31.1, 28.9 and 37.8 g when fed mixed with concentrate feed.     

Nutritional evaluation of cattle manure silage with molasses for ruminants

Two experiments were conducted to evaluate the nutritional quality of cattle manure silage for ruminants. In experiment 1 a silage containing 50% cattle manure, 20% cane molasses (containing 0.4% urea) mixed with water in a 1:1.5 ratio, and 30% corn stover replaced 0, 50, 75 and 100% of corn stover in isonitrogenous diets (1.92% N) containing 70 or 80% corn stover (dry matter (DM) basis) in a 4×2 factorial arrangement. Forty lambs (34.5±3.2 kg body weight (BW)) were used to measure apparent digestibility and nitrogen balance in a completely randomized design with factorial arrangement (4×2) with five lambs per treatment. The cattle manure silage was also evaluated in growing Holstein heifers (212±32 kg BW) replacing 0, 25 or 37.5% of corn stover with cattle manure silage in isonitrogenous diets (2.24% N). Apparent digestibility of DM, organic matter (OM), neutral detergent fibre (NDF) and acid detergent fibre (ADF) were not affected. According to these results, digestibility is not affected by the level of cattle manure silage; however, intake was depressed at the highest levels of silage in lambs. Cattle manure silage may be considered as a potential by-product to be included in heifer's diet up to 37.5%, apparently without affecting performance. Recycling cattle manure through silage for ruminants is a viable alternative. © 1997 Elsevier Science B.V.     

Variability in structural carbohydrates and in vitro digestibility of forages. 4. Fenugreek (Trigonella foenum-graecum)

The chemical composition of ten genotypes of fenugreek, with and without a pretreatment with neutral detergent, has been determined together with dry matter digestibility in vitro. Preliminary extraction with neutral detergent lowered the percentage yield of acid detergent fibre and about 84% of this decrease was observed in the reduction of cellulose level.Dry matter digestibility in vitro was significantly correlated with acid detergent and cellulose when sequential extraction was done. It was considered necessary to use sequential analysis to determine the chemical composition of fenugreek forage.     

Utilization of alkali-treated and neutralized wheat straw-based rations for growing goat kids

Six groups of six goat kids were fed individually for 168 days with wheat straw given various treatments: (1) control; (2) 33 g NaOH/kg straw; (3) 80 g NaOH/kg, partly neutralized with mineral acids; (4) mineral control for 80 g NaOH/kg; (5) 120 g NaOH/kg, partly neutralized with mineral acids, and (6) mineral control for 120 g NaOH/kg straw. The average weight gain was significantly superior (P< 0.05) and the efficiency of dry matter (DM) and energy utilization was the highest with the 80 g NaOH/kg straw treatment. This treatment also gave significantly higher (P<0.05) digestibility of DM, organic matter (OM), neutral detergent fibre (NDF), acid detergent fibre (ADF), nitrogen-free extract (NFE) and hemicellulose than the control and 33 g NaOH/kg straw treatments. Increasing levels of alkali decreased (P<0.05) the digestibility of crude protein (CP) and ether extract (EE). Digestible energy and nitrogen-corrected metabolisable energy (ME_n) (as a percentage of gross energy (GE)) were maximal with 80 g NaOH/kg. The pH value of rumen liquor was the same for the control and the 33 g NaOH/kg and 80 g NaOH/kg treatments, but significantly increased (P<0.05) with the 120 g NaOH/kg straw treatment. The mean values for rumen ammonia nitrogen (NH₃ -N) were the same for the control, the 33 g NaOH/kg, and mineral controls for 80 and 120 g NaOH/kg treatments, but 80 g NaOH and 120 g NaOH/kg straw gave significantly lower values. It is suggested that by partially neutralizing the residual alkali, 80 g NaOH/kg straw can give higher efficiency of energy utilization for growth and digestibility of nutrients compared with 33 g NaOH/kg or the untreated control group, and the extensive use of treated straw in the diets of animals of which a rapid rate of production is not demanded, may be advantageous.     

Rumen degradable nitrogen requirements for optimum microbial protein synthesis and nutrient utilization in sheep fed on finger millet straw (Eleucine coracana) based diet

Studies were conducted to determine the rumen degradable nitrogen (RDN) requirement levels for optimum microbial protein synthesis and nutrient utilization in Nellore rams fed on finger millet straw (FMS) based diet. Thirty six Nellore sheep were randomly divided into four groups of nine animals each using the balanced completely randomized design. Animals in all the groups were fed finger millet straw as a basal roughage and groundnut cake (GNC) was offered daily in two equal halves in the morning (8.00 AM) and evening (4.00 PM) as RDN source. The animals in group I (GI) were fed with ad libitum FMS. Animals in group II, III and IV (GII, GIII, and IV) were offered GNC @ 12.4, 16.6, and 21.1 g RDN/kg digestible organic matter (DOM) along with FMS. The daily total dry matter (DM) and organic matter (OM) intakes linearly increased (P<0.05) with increasing level of RDN supplementation while there was no difference in total DM and OM intake/kg W^0.75 among different experimental groups. The digestibility coefficients of DM (P<0.001), OM (P<0.001), crude protein (CP) (P<0.001), ether extract (EE) (P<0.001), neutral detergent fibre (NDF) (P<0.01) and acid detergent fibre (ADF) (P<0.03) increased quadratically with increasing level of RDN supplementation from GI to GIV. The purine derivatives (PD) excretion, microbial purine absorption and microbial nitrogen supply (MNS g/day) linearly increased (P<0.001) as the level of RDN supplementation increased. There was no difference in nitrogen capture efficiency (NCE) and microbial nitrogen to total urinary nitrogen ratio (MN:UN) among the RDN supplemented groups. This study indicated that 12 g RDN/kg digestible organic matter intake (RDN g/kg DOMI) or 18 g RDN/kg OM apparently digested in the rumen (RDN g/kg DOMR) may be adequate for optimum microbial protein synthesis and digestibility of nutrients, there by improved plane of nutrition in sheep fed on finger millet straw based diet.     

Digestibility of diets containing increasing levels of NaOH-treated or untreated wheat straw

Sodium hydroxide-treated or untreated wheat straw was included in a basal alfalfamaize diet at 0, 10, 20 and 40%. As the level of straw increased, the apparent digestibility of dry matter (DM) and organic matter (OM) by sheep, decreased linearly (P < 0.01), with a faster decrease (P < 0.05) for diets containing untreated straw. The digestibility of DM decreased by 0.22 and 0.41% and OM by 0.24 and 0.42% for treated and untreated straw diets, respectively, with each 1% increase of straw in the diets.Addition of treated straw increased (P < 0.05) digestibility of cell wall constituents (CWC), acid detergent fibre (ADF) and hemicellulose (HC). However, when untreated straw was added, the digestibility of HC was reduced, whereas the digestibility of CWC and ADF was dependent on the level of straw added. Increasing levels of NaOH-treated straw in the diets produced linear increases (P < 0.05) in digestibility of CWC, ADF and HC. However, significant (P < 0.05) linear or quadratic responses were not noted in the digestibility of CWC, ADF and HC with increasing levels of untreated straw in the diet. Apparent digestibility of crude protein was not affected by addition of either NaOH-treated or untreated straw to the diet.In general, although changes in nutrient digestibility of the basal component small, large changes in the digestibility of nutrients in the straw component were apparent and accounted for the major differences in digestibility of the diets. The absence of curvilinearity in the regression equations suggested that there were no associative effects.     

Effects of variety and storage duration on the nutrient digestibility and the digestible and metabolisable energy content of maize fed to growing pigs

The objective of this research was to determine the effects of variety and storage duration on the nutrient digestibility and the digestible (DE) and metabolisable (ME) energy content in maize when fed to growing pigs. Four maize varieties (LS1, LS2, LS3 and LS4) were hand-harvested from the same growing area in China in early October of 2012. The samples were sun dried to about 14% moisture content and then stored in the warehouse of the Fengning Pig Experiment Base at China Agricultural University for 0, 3 or 10 months. Twenty-four barrows of about 33 kg body weight were used and allotted to a completely randomised block design with four diets and six replicate pigs per diet. Pigs were individually housed in metabolic crates. The four experimental diets were formulated by mixing 96.8% of each variety of maize with 3.2% vitamins and minerals. A 5-day collection period followed a 7-day diet acclimation period. The results indicated that the DE and ME contents of maize and the apparent total tract digestibility (ATTD) of organic matter (OM), dry matter, gross energy (GE), neutral detergent fibre, acid detergent fibre (ADF), crude protein (CP) and ether extract (EE) were significantly (p < 0.05) influenced by maize variety and storage duration. With an extension of storage duration from 0 to 10 months, the DE and ME of maize and the ATTD of OM, GE, ADF, CP and EE changed in a quadratic manner (p < 0.05), and 3 months of storage exceeded 0 months of storage by 1.84%, 1.43%, 0.31%, 0.32%, 15.37%, 2.11% and 5.02%, respectively. The DE, ME of maize and the ATTD of OM, GE, ADF, CP and EE decreased by 3.67%, 6.00%, 0.97%, 1.40%, 30.54%, 3.92% and 20.93%, respectively, at 10 months of storage compared to 3 months of storage. No interaction was observed between maize variety and storage duration in DE and ME contents in maize. In conclusion, under the conditions of this study, most of the nutrient digestibility and the DE and ME contents of maize increased from 0 to 3 months and decreased from 3 to 10 months.     

Influence of different fibre sources on digestibility and nitrogen and energy balances in growing pigs

The present study was undertaken to investigate how three different fibre sources, sugar beet pulp, soya bean hulls and pectin residue, constituting 15% of diets for growing pigs, influenced daily body gain, feed conversion, apparent faecal digestibility and nitrogen and energy balances. Eight castrated crossbreed pigs (30-80 kg live weight) were used in a replicated 4 x 4 Latin-square design with one control diet and three fibre containing diets. Daily body weight gain and feed conversion were not affected by the dietary treatments. The apparent faecal digestibility of organic matter (OM) and energy were significantly lower for the fibre diets (OM: 0.81-0.85; energy: 0.78-0.83) compared to the control diet (OM: 0.88; energy: 0.86). The apparent faecal digestibility of crude protein (CP) was lower for the fibre diets (0.71-0.78) compared to the control diet (0.83), although it was only significantly lower for the sugar beet pulp and pectin residue diets. The pectin residue diet, which contained the highest amount of dietary fibre, lignin and insoluble non-starch polysaccharides, had the lowest digestibility of OM, CP and energy. There was a tendency (p = 0.07) for a diet effect on retained nitrogen in proportion to digested nitrogen, where the sugar beet pulp and pectin residue diets had numerically the highest values. Heat production and retained energy in proportion to metabolizable energy intake were not affected by fibre inclusion. It was concluded that the inclusion of sugar beet pulp, soya bean hulls and pectin residue in diets for growing pigs decreased the apparent faecal digestibility and in the diets with sugar beet pulp and pectin residue higher utilization of digested nitrogen for retention compensated for the lower amount of digested nitrogen.     

Influence of enzyme supplementation of diets and cooking–flaking of maize on digestive traits and growth performance of broilers from 1 to 21 days of age

A trial was conducted to study the influence of cooking–flaking (C-F) of maize and enzyme supplementation (ES) of the diet on mucosa morphometry, digestive organ weight, dietary component digestibility and growth performance of broilers from 1 to 21 days of age. There were 4 treatments arranged factorially with 2 heat processings of maize (raw and C-F) and 2 levels (0 and 500 mg/kg) of an enzyme complex with xylanase, protease and α-amylase activity. Dietary treatment did not affect any productive trait from 1 to 21 days of age. However, from 1 to 4 days of age, body weight gain (P<0.01) and feed conversion ratio (P<0.001) were improved by ES of the diet. Intestinal viscosity increased with C-F of maize and decreased with ES of the diet (P<0.001). The effects of ES on intestinal viscosity were more pronounced with C-F than with raw maize (P<0.001) and at younger than older ages (P<0.05). Cooking–flaking of maize increased total tract apparent digestibility of dry matter and organic matter (P<0.05) and of neutral detergent fibre and starch (P<0.001) and tended to improve ether extract (EE) digestibility (P<0.10). In addition, ES improved nitrogen retention (P<0.01) and EE digestibility (P<0.001). Digestibility of neutral detergent fibre and starch increased linearly (P<0.001) with age whereas nitrogen retention and organic matter, EE and gross energy digestibility decreased from 4 to 8 days of age and increased thereafter (P<0.001). The relative weight (g/kg body weight) of the pancreas decreased (P<0.01) and that of the liver increased (P<0.001) with C-F of maize. The relative weight of the proventriculus, gizzard and liver reached a maximum before 6 days of age and that of the small intestine and pancreas at approximately 7.8 days of age (P<0.001). Enzymes increased villus height (P<0.05) but did not affect villus width or villus surface area. It is concluded that C-F of maize improved dietary component digestibility but had no effect on broiler performance at 21 days of age. In addition, ES improved nitrogen retention, EE digestibility and productive performance of broilers but only from 1 to 4 days of age.