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1.
Raw mango ( Mangifera indica L) seed kernels were found to contain tannins (56·5 g kg−1 DM), cyanogenic glucosides (64 mg kg−1 DM), oxalates (42 mg kg−1 DM) and trypsin inhibitory activity (20 TIU g−1 DM). The contents of these anti-nutritive factors were lowered by both soaking and boiling treatments, but boiling was more effective. The in vitro protein digestibility (26·3%) and apparent metabolisable energy (7·88 MJ kg−1 DM) values of raw kernels were low, and these parameters were improved by soaking and boiling. The observed improvements paralleled reductions in tannin contents, indicating that tannins are largely responsible for the poor nutritive value of raw kernels. In experiment 1, diets containing 0, 50, 100, 150 and 200 g kg−1 raw mango seed kernels that replaced maize were fed to 7-day-old White Leghorn cockerels for 14 days. Inclusion of more than 50 g kg−1 raw kernels lowered ( P< 0·05) the weight gains, feed intake and feed efficiency of chicks. High level inclusion of raw kernels had toxic effects, as evidenced by increased mortality. In experiment 2, soaking and boiling treatments improved ( P< 0·05) feed intake of chicks fed on diets containing 100 g kg−1 kernels and reduced mortality. Feed/gain was unaffected by processing. Soaking had no effect, whereas boiling of kernels improved the weight gains. However, weight gains of chicks receiving diets containing 100 g kg−1 boiled kernels were numerically, though non-significantly, lower than those of the maize-control group. It is concluded that raw mango seed kernels are unsuitable as a feed ingredient in chick diets and, that soaking and boiling do not completely overcome the anti-nutritive effects of raw kernels.  相似文献   

2.
Studies were carried out to determine the effect of dietary soybean trypsin inhibitor (SBTI) content on nutrient and energy digestibilities in growing pigs. Six barrows, average initial body weight (BW) 47·8±4·0 kg, were fitted with a simple T-cannula at the distal ileum and fed two diets according to a crossover design. Two maize starch-based diets were formulated to contain 200 g crude protein (CP) kg−1 from either Nutrisoy (a food-grade defatted soy flour) or autoclaved Nutrisoy. The contents of SBTI in the Nutrisoy and autoclaved Nutrisoy diets were 13·4 and 3·0 g kg−1, respectively. The experiment consisted of two periods of 12 days each. The average BW at the start of the first and second experimental periods were 53·3±3·7 and 61·0±5·1 kg, respectively. The average BW at the conclusion of the experiment was 71·8±7·6 kg. The ileal digestibilities of dry matter (DM), organic (OM), energy, CP and all amino acids measured were higher (P<0·01) in pigs fed the autoclaved Nutrisoy diet. The energy digestibility increased from 66·0 to 77·9%, and the CP digestibility increased from 37·4 to 77·1%. The increases in ileal digestibilities of the indispensable amino acids ranged from 27·0 (methionine) to 49·2 (leucine) percentage units. The increases in ileal digestibilities of the dispensable amino acids ranged from 30·2 (aspartic acid) to 50·8 (tyrosine) percentage units. The faecal digestibilities of all criteria measured were also higher (P<0·01) in pigs fed the autoclaved Nutrisoy diet. Furthermore, there was a greater (P<0·01) net disappearance (g kg−1 DM intake) of DM, OM, CP, energy and all amino acids in the large intestine of pigs fed the Nutrisoy diet. In conclusion, feeding diets containing high levels of SBTI decreased both ileal and faecal digestibilities of all criteria measured. The formation of SBTI-enzyme complexes is likely to be responsible for the reduction in protein digestion and amino acid absorption. © 1998 SCI.  相似文献   

3.
Effects of diets containing increasing levels of whole cotton seed (WCS) on feed intake, liveweight gain, feed conversion, feeding margin and carcass characteristics were studied. Diets contained 0, 5, 10, 15, 20 and 30% WCS and were fed ad libitum to growing lambs for 54 days. All diets were approximately isonitrogenous (163–186 g crude protein kg−1 dry matter) and isocaloric (19–20 MJ gross energy kg−1 of dry matter). During the first 28 days, four groups of 10 Karagouniko male lambs with initial liveweights of approximately 17·6 kg were fed diets containing 0, 5, 10 and 15% WCS and then, for the next 26 days, diets containing 0, 10, 20 and 30% WCS, respectively. Lambs fed the 15–30% WCS diet ingested about 20 mg kg liveweight−1 day−1 of free gossypol. At 54 days and liveweights of approximately 34·7 kg, five lambs from each treatment were slaughtered and carcass data were collected. There were significant differences in feed intake, liveweight gain, cooler shrink, rumen contents, intestinal fat and liver weight among the lambs fed these diets. Cooler shrink and intestinal fat, and perirenal fat and the combined weight of intestinal and perirenal fat, were significantly (P < 0·05) correlated. Pelleting of the WCS diets reduced the concentration of free gossypol in these diets. It was concluded that WCS was satisfactory as a feed ingredient for growing sheep and can be incorporated into ruminant diets as a source of energy and protein. No indication of gossypol toxicity was detected. © 1998 Society of Chemical Industry  相似文献   

4.
BACKGROUND: The study was conducted to determine the effect of graded levels of feed intake on apparent (AID) and standardized (SID) ileal digestibilities of crude protein (CP) and amino acids (AA) in diets for piglets. The piglets were surgically fitted with simple T‐cannulas at the distal ileum. The cornstarch–casein–soybean meal‐based diets were fed at three graded levels of feed intake corresponding to 30, 45 and 60 g kg?1 body weight (BW) per day. RESULTS: The AID and SID of most AA were quadratically affected by the feed intake level (P?0.05). Initially, both AID and SID of most AA increased up to 1.9 percentage units as the feed intake level was increased from 30 to 45 g kg?1 BW. Thereafter, these AID and SID values decreased by 2.6 and 2.7 percentage units, respectively, as the feed intake level was further increased from 45 to 60 g kg?1 BW. CONCLUSION: Because the voluntary feed intake is highly variable in piglets after weaning, comparison of ileal AA digestibilities between and within studies may be confounded by variations in feed intake level. Thus, when designing digestibility studies with piglets, a standardization of feed intake should be taken into consideration. Copyright © 2011 Society of Chemical Industry  相似文献   

5.
The effect of feeding newly weaned pigs acidified liquid diets was investigated. The control diet was acidified to about pH 4 with lactic acid (LA). A second diet of the same formulation was acidified to about pH 4 by fermentation with Pediococcus acidilactici (PA). Forty‐eight weaner pigs (weight 7 kg±1 kg, age 24±4 days) were allocated to the two dietary treatments according to a randomised block design and fed ad libitum for 28 days. Food intake, daily gain and water intake were recorded, and a microbial assessment of the liquid diet was conducted. Reducing pH<4.0 in either of the liquid diets was effective in eliminating coliform bacteria. There were no significant differences in any of the performance parameters measured. The average daily liveweight gain overall was 474 and 496±17.8 g d−1 for PA and LA, respectively, with a feed conversion ratio overall of 1.15 and 1.11±0.025 for PA and LA, respectively. Fermentation of liquid diets for newly weaned piglets could provide a more cost effective means of acidifying diets than the use of organic acids. Reducing the pH of the liquid diet to 4.00 by fermentation with Pediococcus acidilactici was a cost effective method of eliminating enteropathogens and spoilage organisms from the diet. © 1999 Society of Chemical Industry  相似文献   

6.
Forty eight and ninety six pigs weaned at 22·6±2·6 days, were allocated to two trials to study the effect of feeding post-weaning diets ad libitum , either as dry pellets (DF) or as meal mixed with water in the ratio 2·5:1 (LF). The trials, lasting 28 days, differed only in the type of trough used to present the liquid feed to the pigs. In both trials the daily gain of LF pigs over the 4 weeks of the trial was significantly ( P< 0·001) better than that of the DF pigs. Daily gains for the two treatment groups were respectively 428 and 343±15 g day−1 in Trial 1 and 454 and 397±10 g day−1 in Trial 2. The feed conversion ratio (FCR) (corrected to fresh weight of dry feed) of LF pigs was significantly poorer ( P< 0·01) than that of DF pigs in both trials primarily as a result of feed wastage by the LF pigs. FCR for the DF and LF pigs was, respectively, 1·31 and 1·89±0·05 in Trial 1. In Trial 2 improvements in the trough design reduced the difference in FCR. FCR for the DF and LF treatments was 1·37 and 1·44±0·02 respectively. In Trials 1 and 2 LF pigs used on average 76% and 35% more water than DF pigs. LF pig produced 12% (Trial 1) and 5·7% (Trial 2) more effluent per unit of liveweight gain than DF pigs. Microbiological examination of the liquid feed system demonstrated that the system acted as a fermenter. Lactobacillus spp proliferated rapidly and became the dominant organism within 5 days and the populations remained relatively constant thereafter. The proliferation of lactobacilli reduced the pH of the liquid feed from approximately 6·0 to between 3·5 and 4·0. At the lower levels of pH the number of coliforms in the feed was significantly reduced.  相似文献   

7.
Using cannulated pigs and a standardised in vitro fermentation system the effect of diet and non‐starch polysaccharides (NSP) on the amount of energy available from microbial fermentation in the large intestine could be predicted. The available energy was calculated from the amounts of short‐chain fatty acids (SCFA) produced. Three diets were investigated: a low fibre diet based essentially on wheat flour (56 g NSP kg−1 feed) and two high fibre diets with added oat bran (93 g NSP kg−1 feed) or wheat bran (102 g NSP kg−1 feed). Colonic fermentation was estimated by in vitro fermentation of freeze‐dried ileal effluent collected from cannulated pigs. The in vitro fermentation method was optimised to use 10 g ileum content litre−1 incubated at pH 6.0 in a fermentor containing faecal slurry consisting of anaerobic mineral salts medium and 50 g litre −1 faeces from pigs fed the same diets as the cannulated pigs. The results demonstrate that it is very important to compensate for the faecal SCFA contribution when calculating the amount of SCFA produced from ileal digesta during in vitro fermentation. The amount of NSP digested in vitro was compared with data obtained from in vivo studies and there was a good agreement between in vivo and in vitro data. We concluded that the integrated in vivoin vitro method is a valuable technique to estimate the effect of diet and NSP on the amount of SCFA produced in the large intestine and when fed the three diets the microbial fermentation in the large intestine provided between 2.4–6.4% of the total available energy. © 1999 Society of Chemical Industry  相似文献   

8.
Pea starch, hulls and cotyledon inner fibres, isolated from pea seeds, were incorporated in N-free diets, on a NDF-content basis, in order to study their effect on the ileal endogenous amino acid (AA) excretion in the growing pig. Maize starch and wood cellulose were selected as references. The inner fibre-containing diet was also supplemented with enzymatically hydrolysed casein (EHC) in order to test the peptide alimentation method on a diet containing a fibre source with a high water-holding capacity (WHC=10·9 g water g−1 DM). The fibres were also analysed by different methods (crude fibre, NDF, ADF, enzymatic–gravimetric method, Englyst method). The fibre content of the inner fibre fraction varied widely from one method to another and ranged from 109 g crude fibre to 480 g AOAC fibre kg−1 DM. Compared to the ‘maize starch+wood cellulose’ diet (11·0 g AA excreted kg−1 DM intake), pea starch had no effect on ileal AA losses (9·6 g), whereas pea hulls slightly increased them (14·2 g). The AA excretion dramatically increased with the incorporation of inner fibres (28·0 g), because of their very high WHC. The addition of EHC increased the output (48·0 g) further, at a level that can hardly be explained only by an increase of the endogenous secretions. The results suggest that the NDF content of grain legume products is not indicative of their effect on the ileal endogenous AA losses in pigs and that the physiological effects of fibres along the gastrointestinal tract are due to both their chemical and physical properties.  相似文献   

9.
Studies were carried out to determine the effect of soybean trypsin inhibitors (SBTI) on exocrine pancreatic secretions in growing pigs. Six barrows with an average initial body weight (BW) of 27·1±1·4 kg were fitted with permanent pancreatic re-entrant cannulas and fed two diets according to a crossover design. Two maize starch-based diets were formulated to contain 200 g kg−1 crude protein from either Nutrisoy (food grade defatted soy flour) or autoclaved Nutrisoy. The concentrations of SBTI in Nutrisoy and autoclaved Nutrisoy diets were 13·4 and 3·0 g kg−1, respectively. The experiment consisted of two periods of 9 days each. The average BW at the start of the first and second experimental periods was 33·5±2·7 and 37·2±3·7 kg, respectively. The average BW at the conclusion of the experiment was 41·8±3·9 kg. The volume of pancreatic secretion was higher (P<0·01) when the Nutrisoy, as opposed to the autoclaved Nutrisoy diet was fed (3804 vs 2634 ml (24 h)−1). The concen-tration of nitrogen and protein and specific activities (units litre−1) of amylase, chymotrypsin and trypsin were lower (P<0·05) in pancreatic juice of pigs fed the Nutrisoy diet. There were no differences (P>0·05) in the total secretions of nitrogen (g (24 h)−1) and total activities (units (24 h)−1) of amylase, lipase, chymotrypsin and trypsin in pancreatic juice of pigs fed the Nutrisoy and autoclaved Nutrisoy diets. However, the total secretion of protein was slightly higher (25·7 vs 22·8 g (24 h)−1; P<0·05) in pancreatic juice of pigs fed the autoclaved Nutrisoy diet, which corresponded with the increase in the secretion of protein-bound amino acids. There was also an increase in the total secretion of free amino acids in pancreatic juice. These studies show no effect of SBTI on the total enzyme activities in pancreatic juice of growing pigs. © 1998 SCI.  相似文献   

10.
Two experiments were carried out to investigate the effect of feeding diets containing faba beans and peas on pancreatic secretions in young pigs fitted with a pancreatic pouch re-entrant cannula. In Experiment 1, eight barrows, with an average initial weight of 8·5 kg, were fed one of two maize starch-based diets formulated to contain 200 g crude protein (CP) kg−1 according to a completely randomised design. In one of the diets, soya bean meal was the sole protein source; in the other diet, soya bean meal and faba beans (cv Fibro; dark-flowering) each supplied 50% of the dietary CP. In Experiment 2, five barrows, with an average initial weight of 18·1 kg, were fed one of two diets according to a two-period change-over design. The diets were formulated to contain 150 g CP kg−1 with peas (cv Ascona or cv Radley) as the sole protein source. In both experiments, the experimental periods consisted of 8 days: 6 days adaptation followed by a 2 day collection of pancreatic juice. The soya bean meal diet and the faba bean diet contained 0.04 and 0.21% tannins (catechin equivalents), respectively. The trypsin inhibitor activities of the Ascona and Radley pea diets were 0·76 and 3·24 mg of trypsin inhibited per gram, respectively. In both experiments, diet did not affect ( P> 0·05) the pancreatic secretions of nitrogen, protein, amylase, lipase and chymotrypsin. In Experiment 1, specific trypsin activity was higher ( P< 0·05) in pancreatic juice from pigs fed the diet containing soya bean meal and faba beans (53700 units litre−1) than for those fed the soya bean meal diet (41200 units litre−1). However, there was no effect ( P> 0·05) when trypsin activity was expressed as total activity (units 24 h−1). It is concluded that the inclu-sion of faba beans and peas in diets for young pigs has only minor effects on exocrine pancreatic secretions.  相似文献   

11.
Twelve sunflower (Helianthus annuus L) cultivars grown in Spain were analysed and tested in experiments with rats. The dehulled seeds contained an average of 32.2 MJ kg−1 dry matter (DM) gross energy, 653 g kg−1 DM fat, 60 g kg−1 DM total non-starch polysaccharides (NSP) and 6 g kg−1 DM Klason lignin. The sunflower seed hulls contained 20.2 MJ kg−1 DM gross energy, 53 g kg−1 DM fat, 562 g kg−1 DM total NSPs and 239 g kg−1 DM Klason lignin. The sunflower samples were dehulled and partially defatted (to ∼17% fat) and included in diets for rats. The dehulled, partially defatted samples contained on average 74.6 g nitrogen kg−1 DM and 1.409 mg g−1 phenolic compounds (chlorogenic acid + caffeic acid + derivative 1 + derivative 2) varying from 0.677 to 2.847 mg g−1. Groups of five growing rats were fed diets (9.38% crude protein) containing one of the sunflower cultivars as the only source of protein. Apparent ileal and faecal digestibilities were determined by using an indigestible marker (Cr2O3) and faecal digestibility based on total faecal collections. Apparent ileal, caecal and faecal digestibilities of organic matter were 81.2–91.5% (P = 0.05), 95.8–97.1% (P = 0.005) and 94.7–95.3% (P = 0.94) respectively. The apparent faecal digestibilities of DM, energy and protein (N × 6.25) were 93.2–93.8%, 93.5–94.3% and 81.6–84.3% respectively with no differences among cultivars. Biological value (BV) ranged between 63.8 and 73.2% (P = 0.0001) and net protein utilisation (NPU) between 59.9 and 69.5% (P = 0.0001). BV and NPU were positively correlated with lysine and threonine contents, but no correlation with the analysed phenolic compounds was detected. © 1999 Society of Chemical Industry  相似文献   

12.
The feeding value of feed grade chickpeas (Kabuli and Desi type) for ruminants and pigs was determined in two studies. Two ruminally fistulated cows were used in the first study to determine the effects of moist heat treatment (127 °C for 10 min) on the ruminal protein degradability of feed grade chickpeas. Heat treatment reduced (P < 0.05) soluble crude protein and increased (P < 0.05) the amount of crude protein associated with neutral detergent fibre for both types of chickpeas. Ruminal degradability of crude protein for Kabuli and Desi chickpeas was reduced by 39 and 33% (P < 0.05) respectively as a result of heating. In the second study, 64 crossbred pigs were each assigned to one of four dietary treatments in a factorial (4 treatments × 2 sexes) design experiment. The experimental barley/wheat‐based diets were supplemented with either soybean meal (control), Kabuli chickpeas (300 g kg−1), Desi chickpeas (300 g kg−1) or field peas (300 g kg−1). Dry matter and gross energy digestibility coefficients, determined using the indicator method, were lower (P < 0.05) for the Desi‐ than for the Kabuli‐supplemented diet. However, no differences were observed in dry matter or gross energy digestibility between the Kabuli chickpea‐supplemented diet and the control or the field pea‐supplemented diet. Diets supplemented with chickpeas or field peas had a lower (P < 0.05) crude protein digestibility than the control diet. Pigs fed either of the chickpea‐supplemented diets during the growing phase gained less (P < 0.05) than pigs fed the control diet. However, during the finishing phase and over the entire experiment, dietary treatment had no effect on pig performance. There were no significant differences in carcass traits between pigs fed any of the four diets. It was concluded that moist heat treatment is an effective method to increase the rumen escape protein value of chickpeas and that the inclusion of feed grade Kabuli or Desi chickpeas in finishing diets up 300 g kg−1 had no detrimental effects on pig performance. © 2000 Society of Chemical Industry  相似文献   

13.
Two experiments were conducted to evaluate the feeding value of yellow-, green- and brown-seeded peas as protein and energy supplements in laying hen diets. In experiment 1, all three types of peas were included in laying hen diets at 0, 200, 400 and 600 g kg-1 replacing wheat and soya bean meal. Layers fed diets containing peas at 200 g kg-1 produced more (P⩽0·05) eggs, had higher (P⩽0·05) egg mass output and better (P⩽0·01) feed conversion than those fed the wheat soya bean meal control diet. With 400 g peas kg-1 in diets, egg production, egg mass and feed conversion were similar (P⩾0·05) to the control diet. Total replacement of soya bean meal with peas (600 g peas kg-1 in diets) reduced (P⩽0·01) egg production, egg mass and feed conversion. A progressive (P⩽0·01) improvement in yolk colour as the level of peas in the diet increased was observed. Shell quality decreased (P⩽0·05) with increasing levels of yellow or brown peas in the diets, however, it seemed not to be affected by green peas. Daily feed intake, egg weight and mortality rates were not affected by dietary treatments. The influence of feeding diets containing yellow or brown peas supplemented with varied levels of methionine on production performance of laying hens was investigated in experiment 2. The dietary treatments consisted of a 400 g kg-1 yellow or brown pea diet supplemented with three levels of methionine to 100, 115 and 130% of the NRC requirements. Methionine supplementation to either 15 or 30% above NRC requirement for laying hens had no significant (P⩾0·05) effect on all production parameters. It can be concluded that the inclusion of yellow, green or brown peas into laying hen diets up to 400 g kg-1 does not affect production performance. The NRC recommendation of methionine requirement for laying hens is adequate to support maximum egg production for diets containing moderate quantities of peas. © 1997 SCI.  相似文献   

14.
The composition of the leaves of cocoyam (Xanthosoma sagittifolium) and of two trees (Trichanthera gigantea and mulberry, Morus alba), their nutritive value in pigs and voluntary intake by pigs were determined. The average protein content ranged from 170 to 240 g kg?1 dry matter (DM) and that of neutral detergent fibres from 218 to 398 g kg?1 DM. The leaves are interesting sources of calcium (up to 69 g kg?1 DM), potassium, iron and manganese. The proteins are well balanced in essential amino acids, with lysine ranging from 43 to 57 g kg?1 proteins. The apparent faecal digestibility was determined by difference in 35 kg pigs fed a diet containing 35% leaf meal. The digestibility coefficients of DM, N and energy were, respectively, 47–57, 33–36 and 51–53%. The digestible energy value ranged from 1.674 to 2.037 kcal kg?1 DM. The voluntary intake of Trichanthera and Xanthosoma was measured in sows weighing 100 kg on average. The intake reached 3.4 kg fresh leaves day?1 (0.51 kg DM) and 1.0–1.1 kg dry leaf meal/day. It is concluded that low energy density is the main limiting factor of tree foliage for pig nutrition but that they are good sources of minerals and well‐balanced proteins. Copyright © 2005 Society of Chemical Industry  相似文献   

15.
Two experiments were conducted to evaluate the effects of phosphorus (P) level and calcium (Ca)/total P (tP) ratio on the efficacy of microbial phytase. Experiment 1 examined the effects of P concentration and microbial phytase inclusion on mineral excretion and pig performance, while experiment 2 examined the effects of Ca/tP ratio and microbial phytase inclusion on mineral excretion and pig performance. In experiment 1, nutrient and mineral digestibility (n = 4) and growth performance (n = 12) were determined in pigs individually fed diets containing (T1) 5.5 g kg?1 tP, 2.3 g kg?1 available P (aP) and 8.0 g kg?1 Ca, (T2) 5.5 g kg?1 tP, 2.3 g kg?1 aP, 8.0 g kg?1 Ca and 750 FYT kg?1 Peniophora lycii phytase, (T3) 4.3 g kg?1 tP, 1.4 g kg?1 aP and 8.0 g kg?1 Ca and (T4) 4.3 g kg?1 tP, 1.4 g kg?1 aP, 8.0 g kg?1 Ca and 750 FYT kg?1 P lycii phytase. In experiment 2, nutrient and mineral digestibility (n = 4) and growth performance (n = 12) were determined in pigs individually fed diets containing (TT1) 4.3 g kg?1 tP and 8.0 g kg?1 Ca, (TT2) 4.3 g kg?1 tP, 8.0 g kg?1 Ca and 750 FYT kg?1 P lycii phytase, (TT3) 4.3 g kg?1 tP and 5.0 g kg?1 Ca and (TT4) 4.3 g kg?1 tP, 5.0 g kg?1 Ca and 750 FYT kg?1 P lycii phytase. All diets were formulated, using standard feeding values for the ingredients, to have similar concentrations of digestible energy (DE) and lysine. In experiment 1, pigs offered the low‐P diets had significantly lower P intake (P < 0.001), faecal P excretion (P < 0.05), Ca intake (P < 0.05) and faecal Ca excretion (P < 0.05) compared with pigs given the adequate‐P diets. These pigs also had significantly lower daily gain (P < 0.01), feed intake (P < 0.05) and feed conversion ratio (FCR) (P < 0.05). The inclusion of phytase in both the adequate‐ and low‐P diets increased the digestibility of energy (P < 0.05) and Ca (P < 0.01) but had no effect on pig performance. In experiment 2, lowering the Ca/tP ratio from 1.85:1 to 1.15:1 increased the DE content of the diet (P < 0.05). The inclusion of phytase increased (P < 0.05) the digestibility of protein (0.874 versus 0.840, SEM 0.009) and Ca (0.427 versus 0.380, SEM 0.019) as well as the DE content of the diet (14.47 versus 14.26 MJ kg?1, SEM 0.073). There was a significant ratio × phytase interaction (P < 0.5) for P digestibility. Microbial phytase significantly increased P digestibility when added to the 1.15:1 ratio diet but had no effect when added to the 1.85:1 ratio diet. The inclusion of microbial phytase increased feed intake (2.16 versus 2.00 kg day?1, SEM 0.05; P < 0.05) and weight gain (0.893 versus 0.818 kg day?1, SEM 0.022; P < 0.05). Lowering the Ca/tP ratio resulted in a significant improvement in FCR (2.32 versus 2.40 kg kg?1, SEM 0.03; P < 0.05). In conclusion, the beneficial effects of microbial phytase supplementation of pig diets are adversely affected by a wide Ca/tP ratio. © 2002 Society of Chemical Industry  相似文献   

16.
The utilization of abundantly available animal feed grade wheat (AFW) as a replacement for conventional and costly cereal supplement in lamb feeding to lower the cost of mutton production was explored. Thirty‐five growing lambs divided into five equal groups and were fed diets containing 0, 118, 235, 353 or 470 g kg?1 AFW replacing equal quantity of maize. The diets were fed in the form of composite feed mixture, which had a roughage (Prosopis cineraria leaves) to concentrate ratio of 25:75. Dry matter intake (DMI) was not different in these groups, ranging from 35 to 42 g kg?1 body weight, while AFW inclusion linearly (P < 0.05) reduced DMI. The digestibility coefficients of dry matter (DM), organic matter (OM), crude protein (CP) and cellulose were not affected by AFW addition, whereas neutral detergent fibre and acid detergent fibre digestibility coefficients were reduced (P < 0.05). The digestible CP content (142.7–162.7 g kg?1 diet) increased (P < 0.01) linearly with increased AFW inclusion levels. However, AFW additions did not affect metabolizable energy (ME) value of diet (10.2–10.5 MJ kg?1 diet DM). Digestible CP intake was similar but digestible DM and OM intake tended to decrease (P < 0.05) linearly when expressed in terms of g kg?1 W0.75. ME intake (MJ d?1) was not different among the diets but showed linear (P = 0.041) reducing trends with increasing AFW levels in diet. The efficiency of ME and N utilization for unit gain was also not affected by AFW incorporation. N retained as g d?1, percentage of intake and percentage of absorbed ranged from 15.4 to 19.5 g, 49.7% to 60.3% and 62.6% to 74.6%, respectively. Intake and utilization of dietary N was not affected but urinary N excretion reduced (P < 0.05) linearly by AFW. Daily microbial N (MN) flow estimated by urinary purine derivative excretion was significantly (P < 0.01) higher for lambs fed a diet with AFW 235 g kg?1 (3.05 g MN) and 353 g kg?1 (2.51 g MN) compared to without AFW diet (1.31 g MN). MN when expressed as g kg?1digestible organic matter intake (DOMI) and microbial protein g kg?1 digestible organic matter apparently fermented in rumen (DOMR) followed a similar trend. During the growth trial, lambs fed diets containing AFW (353 g kg?1), which replaced 75% maize had higher total gain (14 kg, P < 0.05) and average daily gain (ADG 154 g, P < 0.05). However, feed efficiency (feed consumed kg?1 live weight gain) was not different. Rumen pH and microbial enzyme activities studied 4 h post feeding revealed that AFW did not affect rumen pH, which ranged from 5.95 to 6.30. Similarly, carboxymethyl cellulase and β‐xylosidase enzyme activities were not different among treatments, but AFW inclusion linearly (P = 003) increased carboxymethyl cellulase enzyme activities. The α‐amylase enzyme activity differed significantly (P < 0.05) and was highest (22.6 IU) in groups where AFW replaced maize completely. It was concluded that, in lambs reared under intensive system for mutton production on high concentrate diets, conventional and costly energy supplements like maize can be replaced up to 75% with a low‐cost animal feed grade wheat to economize on cost of production. However, more studies are required to confirm these inclusion levels for greater economic returns. Copyright © 2007 Society of Chemical Industry  相似文献   

17.
Fertilisation of herbage with Na can increase acceptability to cows, but the influence of fertiliser rate and fertilisation by K is unknown. In experiment 1, ten cows were grazed on pasture plots that had just been fertilised with 0–132 kg-Na ha−1 (current Na) and had received 0–64 kg-Na ha−1 in the previous grazing season (residual Na). Herbage Na concentration increased in proportion to current Na from 2·7 to 4·9 g-Na kg−1 dry matter (DM) and also increased with increasing residual Na from 2·2 to 4·5 g-Na kg−1 DM. Herbage K concentrations were low (10 g kg−1 DM at 0 kg-Na ha−1) and were only slightly reduced by Na fertiliser. Herbage Mg and Ca concentrations and DM digestibility were maximum at 66–99 kg-current-Na ha−1. Cows grazed current-Na-fertilised plots to a lower height and spent more time grazing them. In experiment 2, pasture plots received no fertiliser, low and high isomolar and independent applications of Na and K or a combination of the two. The herbage was more mature than in experiment 1 and Na concentration of the herbage without Na fertilizer was high (5 g kg−1 DM). Na fertiliser, therefore, only slightly increased Na concentration, more in clover than in grass, and had little effect on K concentration. K fertiliser increased K concentration from 16 to 20 g kg−1 DM and reduced Na concentration to 3·5 g kg−1 DM. Sodium fertiliser, therefore, only increased the acceptability of herbage to cattle when herbage Na concentrations were initially low (less than 5 g kg−1 DM) and were increased substantially by the application of the fertiliser. © 1998 SCI.  相似文献   

18.
Analysis of black plum (Vitex doniana) indicated a fruit with useful nutritional value in tropical African diets (crude protein 27·5, lipid 49·5, sugars 842 g kg?1 DM; moisture 488 g kg?1 FW) and possibly a good shelf-life.  相似文献   

19.
In two factorial experiments with a total of 81 growing pigs, the effects of antithyroid compounds and rapeseed meal (RSM) diets differing in glucosino-late content were tested without or with supplementary iodine. In Experiment 1, a 4×3 factorial arrangement was used to investigate the effects of antithyroid compound inclusion and supplementary iodine. Pigs received a grain–soya bean meal diet (control) or this diet with 250 mg kg-1 methimazole (MMI), 1000 mg kg-1 thiocyanate (SCN- as KSCN) or 80 g kg-1 high glucosinolate RSM (9·5 mmol glucosinolates kg-1), each diet supplemented without or with iodine; 0, 125 μg kg-1 (requirement) or 500 μg kg-1. In Experiment 2, a 5×3 factorial arrangement was used to study the effects of dietary glucosinolate content and iodine supplementation. Pigs received a grain–soya bean meal diet or four diets with 160 g kg-1 RSM differing in glucosinolate content (0·6, 2·4, 6 or 19 mmol kg-1 diet), each diet supplemented with iodine: 62·5 μg kg-1, 125 μg kg-1 (requirement) or 250 μg kg-1. Irrespective of the iodine dosage, MMI suppressed production of thyroxine and resulted in goitre, myxoedema and cretinism. SCN- induced clinical hypothyroidism when there was no supple-mental iodine. Despite high iodine supplementation, glucosinolate load (19 mmol kg-1 diet) decreased growth, feed intake, iodine store of the thyroid and serum concentration of thyroid hormone and resulted in goitre formation. In the case of diets with ⩽6 mmol glucosinolates kg-1, iodine prevented antithyroid effects. However, more iodine was required by these pigs than by control animals to a high T4 serum concentration. The lowest glucosinolate level tested (0·6 mmol kg-1 diet) yielded the same thyroid hormone status and thyroid weight as the control, however, the iodine content of thyroid gland was decreased. In conclusion, iodine administration prevents the effects of a low glucosinolate intake only, by overcoming the depressed thyroxine released of the thyroid, resulting in regression of goitre. © 1997 SCI.  相似文献   

20.
Leaves from the tree legumes Gliricidia (Gliricidia sepium) and Calliandra (Calliandra calothyrsus) were fed as supplements (200 g dry matter) to sheep (n=3) given a basal diet of barley straw ad libitum. Tree leaves were fed either freshly harvested (F=fresh) or after drying at 60°C in a forced draught oven (D=dried). Voluntary intakes, digestibility and aspects of nitrogen (N) and phenolic compound metabolism were measured in all sheep. Drying decreased the condensed tannin (CT) content of Calliandra (F 117, D 82 g CT kg−1 DM). Total phenolics (TP) were significantly decreased when Gliricidia was dried (F 39, D 21 g TP kg−1 DM), and CT content was reduced from 20 g CT kg−1 DM to zero. Sheep given Gliricidia had higher rumen ammonia concentrations (73–85 mg N litre−1) than did sheep given Calliandra (37–40 mg N litre−1). For both species, drying significantly increased the voluntary consumption of straw, increased DM digestibility, decreased faecal N excretion and increased N balance. For calliandra, drying decreased the apparent degradability of N in the rumen (DNR) from 0·40 to 0·28 g N g−1 N ingested, and increased the apparent digestibility of N (ADN) in the post-ruminal tract from 0·20 to 0·52 g N absorbed g−1 N flowing into the small intestines. For Gliricidia, DNR decreased from 0·64 to 0·51 and ADN increased from 0·41 to 0·56. There were no significant effects of drying on rates of microbial N synthesis. The above changes were discussed in relation to changes in tannin content and it was concluded that drying facilitates the formation of protein–tannin complexes which protect proteins from degradation in the rumen. These proteins are subsequently released in the small intestines, thereby promoting an increased efficiency of dietary N utilisation. ©1997 SCI  相似文献   

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