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1.
Seventy‐two entire male pigs (40.4 ± 1.0 kg) were used to study the effects of increasing crude fibre (CF) level in the diet and maintaining the digestible energy (DE) content of the diet by increasing dietary fat inclusion on pig performance and nutrient digestibility in a 3 × 2 factorial experiment. Productive performance and nutrient digestibility were determined in individually fed pigs offered expander‐processed pelleted diets ad libitum containing three levels of CF (50, 60 and 70 g kg?1) and two levels of fat supplementation (25 and 50 g kg?1) until slaughter at 100 kg. All diets were expander processed at 105 °C for 5 s at 35 bar pressure having been previously conditioned at 85 °C for 5 s. All diets were formulated to have similar concentrations of digestible energy (13.5 MJ kg?1) and lysine (10 g kg?1) and the fat source was a 60:40 blend of tallow and palm oil. The increase in dietary CF level decreased (P < 0.05) the apparent digestibility of crude protein, organic matter (OM) and energy, while the inclusion of 50 g kg?1 fat decreased (P < 0.01) OM and energy digestibility. The inclusion of 50 g kg?1 fat in the diet increased (P < 0.01) ether extract digestibility at the 50 and 60 g kg?1 CF levels; however, fat inclusion had no effect at the 70 g kg?1 CF level. There was no CF × fat interaction in any growth criteria. The inclusion of 50 g kg?1 fat in the diet significantly reduced (P < 0.05) feed intake (2.28 versus 2.43 kg day?1, SEM 0.039), average daily gain (ADG; 0.877 versus 0.927 kg day?1, SEM 0.017) and DE conversion ratio (36.1 versus 35.0 MJ kg?1, SEM 0.40). The increase in dietary CF level decreased (linear, P < 0.05) feed intake (2.45 versus 2.32 versus 2.29 kg day?1, SEM 0.040), ADG (0.940 versus 0.896 versus 0.872 kg day?1, SEM 0.021) and kill‐out proportion (740 versus 741 versus 730 g kg?1, SEM 3.6). In conclusion, increasing both the CF level and supplementary fat inclusion rate had a negative effect on pig growth performance and nutrient digestibility. © 2002 Society of Chemical Industry  相似文献   

2.
BACKGROUND: The present research was conducted to investigate the influences of supplementation with different levels of folic acids in diet on the performance of lactating sows. Twenty Landrace × Yorkshire sows received the same basal corn–soybean diets (folic acid, 1.3 mg kg?1) from gestation to parturition (day 107). After parturition, sows were allotted to four treatments: control group (folic acid supplementation level, 0 mg kg?1), group 1 (12.5 mg kg?1), group 2 (50 mg kg?1) and group 3 (100 mg kg?1), with five replicates of one sow. The experiment lasted for 21 days. RESULTS: (1) Folic acid increased milk production (P > 0.05). (2) Compared with the control, supplementation with folic acid (100 mg kg?1) increased the concentration of butter fat, total substance and non‐lipoid substance significantly (P < 0.01), the concentration of milk protein was also significantly increased in group 2 and group 3 (P < 0.01) in milk. (3) Folic acid supplementation could increase litter weaning weight, average piglet weaning weight and average piglet daily gain (P > 0.05). CONCLUSION: These results suggested that supplementation with folic acid in the diets of lactating sows increases milk production, improved milk quality and the performance of piglets. Copyright © 2011 Society of Chemical Industry  相似文献   

3.
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   

4.
A 3 × 2 factorial experimental design was used to investigate the interaction between threonine level (8.6, 10.5 or 12.1 g kg?1) and an antimicrobial growth promoter (0 or 60 mg kg?1 avilamycin) in piglet starter diets. Three hundred and sixty weaned piglets (24 d of age; 5.9 kg live weight) were blocked on the basis of live weight and assigned to one of six dietary treatments. The treatments were (1) 8.6 g kg?1 threonine and avilamycin, (2) 10.5 g kg?1 threonine and avilamycin, (3) 12.1 g kg?1 threonine and avilamycin, (4) 8.6 g kg?1 threonine and no avilamycin, (5) 10.5 g kg?1 threonine and no avilamycin and (6) 12.1 g kg?1 threonine and no avilamycin. The diets were formulated to have identical concentrations of digestible energy (16 MJ kg?1) and total lysine (16 g kg?1). There was no interaction between threonine and avilamycin in any performance variable measured. Neither the level of threonine nor the inclusion of avilamycin in the diet had any effect on feed intake, average daily gain or food conversion ratio. There was a significant interaction between threonine level and avilamycin inclusion in the apparent digestibility of dry matter, organic matter, nitrogen, ash, neutral detergent fibre and gross energy and also digestible energy content. In the absence of avilamycin, there was a linear increase in nutrient digestibility to increased threonine levels in the diet. However, in the presence of avilamycin there was a quadratic response to increased threonine levels. In conclusion, optimum piglet performance was achieved at a threonine level of 8.6 g kg?1 and there was no advantage to avilamycin inclusion under current conditions. Copyright © 2005 Society of Chemical Industry  相似文献   

5.
The present study was conducted to evaluate the effect of feed‐grade enzyme supplementation in diets with varying levels of energy on the performance of growing and laying Japanese quails. Day‐old Japanese quails, 504 in number, were subjected to six dietary treatments with six replicates at each treatment. Each replicate had 14 chicks. The dietary treatments consisted of three energy levels ie 12.15 MJ (2900 kcal), 11.30 MJ (2700 kcal) and 10.48 MJ (2500 kcal) ME kg?1 diet and two enzyme levels (0 and 0.5 g kg?1 diet). A metabolism trial was conducted at the fourth week of age. At the end of week 5, 10 quails (five of each sex) per treatment were sacrificed for carcass characteristics and 20 female quails from each of the six dietary groups were housed in individual laying cages and fed respective layer diet to study the laying performance and egg quality up to 20 weeks of age. Body weight gains of quails fed 12.15 MJ or 11.30 MJ ME kg?1 diets were significantly higher (p < 0.01) than those fed diets with 10.46 MJ ME kg?1 diet. Feed intake was significantly lower (p < 0.01) in birds that received diet with 12.15 MJ ME kg?1 than in birds that diets containing either 11.30 or 10.46 MJ ME kg?1 diet. Feed conversion ratio (p < 0.01) was best at 12.15, followed by 11.30 and 10.46 MJ ME kg?1 diet. Enzyme supplementation did not improve the growth performance, feed intake or feed conversion efficiency of quails. Enzyme addition also did not influence nitrogen retention or energy or dry matter metabolizability. The carcass characteristics did not differ because of energy or enzyme supplementation. Feed intake increased significantly (p < 0.01) as the dietary energy level decreased. The egg production and quality characteristics remained almost similar in all the dietary treatments. It was concluded that the optimum dietary energy level for quail was 12.15 MJ (2900 kcal) ME kg?1 during the growing phase and 11.30 MJ (2700 kcal) ME kg?1 during the laying phase. Addition of feed enzymes to conventional diets containing varying levels of maize, soyabean meal, fish meal and deoiled rice bran was not beneficial to improve growth, carcass traits, egg production performance or nutrient utilization. Copyright © 2004 Society of Chemical Industry  相似文献   

6.
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   

7.
BACKGROUND: Plant breeders have attempted to improve the nutritonal value of lucerne (alfalfa) by selecting for higher protein and lower fibre concentrations. Although targeted at ruminants, such changes could also improve the nutritional value of lucerne for monogastrics. The objective of this study was to determine the effects of graded levels of dehydrated lucerne meal on nutrient digestibility, performance and carcass traits of swine. RESULTS: The digestibility of dry matter, protein and energy declined linearly (P < 0.05) as the level of lucerne meal in the diet increased. Including lucerne meal at levels greater than 75 g kg?1 was detrimental to the growth rate of pigs during the growing period. During the finishing period, inclusion of lucerne meal at 75 and 150 g kg?1 resulted in improvements in weight gain and feed intake. Carcass traits were generally unaffected by lucerne inclusion. CONCLUSION: Lucerne meal may have greater potential for inclusion in diets fed to growing–finishing pigs than previously realized. To maximize pig performance, lucerne meal should be limited to less than 75 g kg?1 diet during the growing period, while it is possible to go as high as 150 g kg?1 diet during the finishing period without detrimental effects on performance. Copyright © 2008 Society of Chemical Industry  相似文献   

8.
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   

9.
The nutritive value of transgenic lupin seeds (Lupinus angustifolius L) with higher contents of methionine was evaluated with broiler chickens. The crude protein, methionine and cysteine contents in the conventional and transgenic lupins were 322 and 324, 2.0 and 4.5, and 3.6 and 3.7 g kg?1 dry matter respectively. In the feeding trial, conventional and transgenic lupins with hulls were incorporated into a maize–soyabean meal diet at 250 g kg?1 level and the diets were fed to female broiler chicks from 6 to 20 days of age. All diets were balanced to contain similar levels of apparent metabolisable energy (AME), lysine and sulphur‐containing amino acids. The levels of free methionine added to the maize–soyabean meal control, conventional lupin and transgenic lupin diets were 2.2, 2.8 and 2.2 g kg?1 respectively. Weight gain and feed intake were not influenced by dietary treatments, but feed/gain tended to be higher (P = 0.09) in birds fed lupin diets compared with those fed the control diet. Feed/gain of birds fed the conventional lupin diet was higher (1.82 vs 1.74) than for those fed the transgenic lupin diet. These results showed that the supplemental methionine required in poultry diets containing 250 g kg?1 lupin can be lowered by 0.6 g kg?1 diet by the use of high‐methionine lupins. The AME values of conventional and transgenic lupins were determined to be 9.42 and 10.18 MJ kg?1 dry matter respectively. The higher AME value in transgenic lupins may be related to the lower content of soluble non‐starch polysaccharides (45.6 vs 60.7 g kg?1 air‐dry basis). Data on ileal amino acid digestibility indicate that the amino acids in transgenic lupins are as digestible as those in conventional lupins. © 2002 Society of Chemical Industry  相似文献   

10.
BACKGROUND: We hypothesized that eating a food containing saponins (SAP), or tannins (TAN) prior to foods containing the alkaloids gramine (GRA) or 5‐methoxy‐N,N‐dimethyltryptamine (TRP) would provide benefits not possible when the alkaloid‐containing foods were eaten alone. METHODS: In Trial 1, four groups of five lambs were first offered food with SAP for 30 min followed by food with either GRA or TRP for 3.5 h in a 2 × 2 factorial arrangement of a completely randomized design that included alkaloid (GRA or TRP) with or without SAP. In Trial 2 TAN replaced SAP. All foods were isocaloric (3.3 Mcal kg?1) and isonitrogenous (14% crude protein). Foods, fecal and urine samples were collected and analyzed for dry matter intake and apparent digestibility of dry matter, energy (in megajoules, MJ), nitrogen (N), and neutral detergent fiber. RESULTS: Supplemental SAP did not affect digestibility of the parameters tested (P > 0.10). Supplemental TAN increased digestibility of N (g kg?1, P = 0.04), N retained (g day?1, P = 0.07), N digested (g day?1, P = 0.06), and N retained/N consumed (g kg?1, P = 0.07). However, digestibilities of dry matter (g kg?1, P = 0.0026), energy (MJ 1000 MJ?1, P = 0.003), neutral detergent fiber (g kg?1, P = 0.008), and digested N retained (g kg?1, P = 0.07) were lower for lambs fed TAN than for unsupplemented animals. CONCLUSIONS: Tannin supplementation can improve retention of nitrogen in animals fed alkaloid‐containing grasses such as reed canarygrass and tall fescue. Combinations of forages with complementary primary and secondary compounds enable animals to maintain intake and improve nutrient utilization. Copyright © 2012 Society of Chemical Industry  相似文献   

11.
BACKGROUND: The increase in drug‐resistant bacteria and the ban on antibiotic growth promoters worldwide make the search for novel means of preventing bacterial infection and promoting growth performance imperative. In this sense, antimicrobial peptides are thought to be ideal candidates owing to their antimicrobial properties, broad spectrum of activity and low propensity for development of bacterial resistance. The aim of the present study was to investigate the effect of dietary supplementation with antimicrobial peptide‐P5 (AMP‐P5) on weanling pig nutrition. RESULTS: A total of 240 weanling pigs were allotted to four treatments on the basis of initial body weight. There were four replicates in each treatment, with 15 pigs per replicate. Dietary treatments were negative control (NC, basal diet without antimicrobial), positive control (PC, basal diet + 1.5 g kg?1 apramycin), basal diet with 40 mg kg?1 AMP‐P5 (P5‐40) and basal diet with 60 mg kg?1 AMP‐P5 (P5‐60). Pigs fed the PC or P5‐60 diet showed improved (P < 0.05) overall growth performance, apparent total tract digestibility of dry matter, crude protein and gross energy and reduced (P < 0.05) faecal and intestinal coliforms compared with pigs fed the NC diet. CONCLUSION: The results obtained in this study indicate that dietary supplementation with 60 mg kg?1 AMP‐P5 has the potential to improve the growth performance and apparent total tract digestibility of nutrients and reduce coliforms in weanling pigs. © 2012 Society of Chemical Industry  相似文献   

12.
The nutritive value of transgenic peas expressing an α‐amylase inhibitor (α‐Ai1) was evaluated with broiler chickens. The effects of feeding transgenic peas on the development of visceral organs associated with digestion and nutrient absorption were also examined. The chemical composition of the conventional and the transgenic peas used in this study were similar. In the two feeding trials, that were conducted normal and transgenic peas were incorporated into a maize–soybean diet at concentrations up to 500 g kg?1. The diets were balanced to contain similar levels of apparent metabolisable energy (AME) and amino acids. In the first trial, the birds were fed the diets from 3 to 17 days post‐hatching and with levels of transgenic peas at 250 g kg?1 or greater there was a significant reduction in body weight but an increase in feed intake resulting in deceased feed conversion efficiency. In the second trial, in which the birds were fed diets containing 300 g kg?1 transgenic peas until 40 days of age, growth performance was significantly reduced. It was also demonstrated that the ileal starch digestibility coefficient (0.80 vs 0.42) was significantly reduced in the birds fed transgenic peas. Determination of AME and ileal digestibility of amino acids in 5‐week‐old broilers demonstrated a significant reduction in AME (12.12 vs 5.08 MJ kg?1 DM) in the birds fed the transgenic peas. The AME value recorded for transgenic peas reflected the lower starch digestibility of this line. Ileal digestion of protein and amino acids was unaffected by treatment. Expression of α‐Ai1 in peas did not appear to affect bird health or the utilisation of dietary protein. However, the significant reduction in ileal digestion of starch in transgenic peas does reduce the utility of this feedstuff in monogastric diets where efficient energy utilisation is required. Copyright © 2006 Society of Chemical Industry  相似文献   

13.
Dried, ground willow (Salix aquatica) treated with 33 g sodium hydroxide kg?1 (7.5M solution) was fed to sheep in pelleted diets containing 0, 100, 200, 300, 400 g treated willow kg?1. Apparent digestibility coefficients of dietary dry matter, organic matter and energy declined linearly with increasing content of treated willow. Extrapolation of these relationships gave estimated apparent digestibility values for treated willow of 0.42 and 0.40 for dry matter (DM) and gross energy respectively. The apparent digestibility of acid-detergent fibre was shown to be 0.36. The metabolisable energy content of the treated willow was calculated to be 5.7 MJ kg?1 DM. The high copper content (579 mg kg?1) of the treated willow did not appear to have any deleterious effects on the animals during this short-term experiment as shown by the normal liver copper concentrations in the sheep at the end of the experiment.  相似文献   

14.
BACKGROUND: A meta‐analysis of data containing 127 different dietary treatments with 593 goats from 30 published studies was performed to explain the effects of foliage supplementation to low‐quality roughages on intake, digestibility and N utilisation in goats. RESULTS: Basal dry matter (DM) intake decreased linearly with increasing foliage level (FL) in diets and foliage crude protein (CP) intake, whereas total DM intake increased linearly with increasing FL and CP intake from foliages and quadratically with increasing concentration of neutral detergent fibre (NDF) in foliages. The digestibility of DM and CP increased linearly with increasing FL and CP concentration in basal roughages and foliage CP intake. The greater concentration of NDF in foliages and roughages decreased CP digestibility linearly. Intakes of digestible DM and CP increased quadratically with increasing FL, with plateau levels of 36.4 and 5.52 g kg?1 (body weight)0.75 in response to 490 and 740 g kg?1 FL respectively. Faecal N, urinary N and N retention increased linearly with increasing FL and foliage CP intake. CONCLUSION: Responses of goats fed basal roughages supplemented with foliages are influenced by the quality and quantity of foliages and quality of roughages. Up to 490 g kg?1 FL can be incorporated in diets for better feed utilisation and animal performance, beyond which nutrient utilisation may be adversely affected. Copyright © 2009 Society of Chemical Industry  相似文献   

15.
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   

16.
The need for a critical amino acid (AA) profile for growth, immune response and N utilisation of naked neck broilers during summer was studied. Day‐old naked neck chicks (n = 198) from a single hatch were distributed into 24 groups (four dietary regimens (DRs) with six replicates each) having eight birds in each replicate. The first diet was based on crude protein (CP) and metabolisable energy (ME) (13.40 MJ) as per NRC recommendations (DR1). In the second diet, the CP content was reduced through supplementation of synthetic AAs to achieve critical AA contents as suggested by NRC with 13.40 MJ ME (DR2). In the third diet critical AAs were supplemented to achieve their level at 108% of NRC with 12.6 MJ ME (DR3), while in fourth diet critical AA concentration was reduced to 94% (DR4) of NRC with 12.6 MJ ME to match the ratio of ME to AA concentration as that of NRC (1994). Diets were formulated separately for starter (0–3 weeks) and finisher (3‐6 weeks) phases. A metabolism trial was conducted at the third week of age. At 3 and 6 weeks of age eight birds (four of each sex) per treatment were killed to study the growth of immune organs (Bursa of Fabricius, thymus and spleen). Immune response was studied at the fourth week of age. During the starting phase, the birds fed DR1 and DR2 having 13.40 MJ ME kg?1 diet had higher body weight (P < 0.044) gain (P < 0.048) and better feed conversion ratio (FCR) (P < 0.001) as compared to DR3 and DR4 (12.6 MJ ME kg?1 diets). However, better (P < 0.001) CP efficiency (CP intake kg?1 gain) and lower feed cost kg?1 gain (P < 0.001) was recorded in DR4. A similar trend was also observed during the finisher phase. Dietary regimens had no effect on dry matter (DM) metabolisability, N intake or output and N retention. There was no difference in the weight of immune organs (bursa, thymus and spleen) between dietary treatments at either 3 or 6 weeks of age. The cell mediated and humoral immune response was also not different between the NRC and modified NRC levels. Copyright © 2007 Society of Chemical Industry  相似文献   

17.
The objective of the present experiment was to study the effect of flaxseed processing on nitrogen corrected true metabolizable energy (TMEn) values for adult roosters. Flaxseed was processed as pelleted, autoclaved or microwave roasted. Leghorn roosters were used for the TME determination procedure. The TMEn value of flaxseed batch A, 14.48 MJ kg?1 DM, was significantly (P < 0.05) increased to 17.89 MJ kg?1 DM by three‐time repeat‐pelleting, or to 18.07 MJ kg?1 dry matter (DM) by autoclaving, respectively. Microwave roasting also significantly (P < 0.05) increased the TMEn value of flaxseed batch B by 22%. The TMEn improvement observed due to processing was accompanied by increased ether extract utilization. The apparent ether extract digestibility of flaxseed batch A, 61.2%, was very significantly (P < 0.01) increased to 81.5 and 83.2% by processing as repeat‐pelleting and autoclaving, respectively. Microwave roasting also significantly (P < 0.05) increased the apparent digestibility of ether extract for flaxseed batch B from 49.1 to 64.4%. Proper flaxseed processing as pelleting, autoclaving and microwave roasting led to higher TMEn values for Leghorn roosters, mainly as the result of increased ether extract utilization. Copyright © 2004 Society of Chemical Industry  相似文献   

18.
The effect of fructooligosaccharide on protein digestibility and mineral absorption was studied in rats fed diets containing 5 g kg?1 fructooligosaccharide, 5 g kg?1 cellulose/fructooligosaccharide (1:1) or 5 g kg?1 cellulose as a source of dietary fibre. Addition of cellulose/fructooligosaccharide or fructooligosaccharide to the diet did not significantly modify the daily food intake and food efficiency. However, the fructooligosaccharide‐fed group showed a significant decrease in body weight gain compared with cellulose‐fed groups. Faecal excretion was significantly lower when there was fructooligosaccharide intake, despite there being no significant differences in cellulose‐fed groups. Intake of fructooligosaccharide produced an increase in caecal content and an enlargement of the caecal wall. This trophic effect could be attributed to short‐chain fatty acids produced from the anaerobic fermentation of fructooligosaccharide by intestinal bacteria. Cellulose/fructooligosaccharide enhanced the apparent absorption and apparent retention of Ca, Mg, Zn and Fe. Fructooligosaccharide‐fed rats experienced an increase in apparent absorption and apparent retention of Mg compared with cellulose‐fed rats. Fructooligosaccharide intake at the lowest dose was enough to provide a desirable effect on mineral bioavailability in rats without any modification of nutritional parameters. © 2002 Society of Chemical Industry  相似文献   

19.
Limits for cadmium and lead concentrations in food animal products have been established independently, whereas these two toxic metals often co‐exist in polluted regions. Weaned pigs (60) were allocated to ten treatments: control; low (0.5 mg kg?1), medium (1 mg kg?1) or high cadmium (2.5 mg kg?1) in feed; low (5 mg kg?1) medium (10 mg kg?1) or high (25 mg kg?1) lead in feed; and low, medium and high cadmium plus lead in feed. Growth rates and concentrations of cadmium and lead in body tissues (kidney, liver, spleen, lungs, heart, testicle, ribs, hair and teeth) were measured after 137 days. There was a similar reduction in weight gain for pigs in the cadmium and lead treatments, compared with the control, and a greater reduction for the pigs in the cadmium plus lead treatments. The reduction increased with the level of metal included. There was an increase in cadmium concentration of all tissues and blood with increasing feed cadmium concentration, which was usually less when lead was also included in the feed. There was also an increase in tissue lead concentration with increasing dietary lead, and this was in most cases increased when cadmium was also included in the feed. The most sensitive tissues for cadmium and lead exposure were the kidney, liver, hair and teeth, and regression equations were developed for the accumulation rates in these tissues. Tissue and blood cadmium concentrations increased gradually with increasing dietary lead, whereas tissue lead concentration was not sensitive to dietary cadmium, except in the ribs and heart. In a second experiment, 10 sows were allocated to a control diet or the same diet but with a supplement of cadmium and lead. The birth weight of piglets was decreased by the supplement and their mortality increased. Lead accumulated most in the ovary and oviduct of the sows, and there were increases in the lead and, to a lesser extent, cadmium concentrations of tissues of the piglets from these sows. Copyright © 2003 Society of Chemical Industry  相似文献   

20.
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 © 2008 Society of Chemical Industry  相似文献   

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