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1.
Two experiments were carried out to determine the effects of diets containing fermented and amino acid (AA)-supplemented malted sorghum sprout (MSP) on performance, nutrient utilisation and feed cost analysis of growing pigs. In experiment 1 (digestibility trial), 12 pigs were individually housed in metabolic crates, equipped with feeding and watering troughs which also allow for separate collection of faeces and urine. Data collection lasted for 7 days during which feed intake and faecal output were weighed, with daily storage of collected faeces at ?4 °C. Four diets, a basal diet, basal plus malted sorghum sprout (B?+?MSP), basal plus fermented malted sorghum sprout (B?+?FMSP) and basal plus amino acids plus malted sorghum sprout (B?+?AA?+?MSP), were tested. Samples of test ingredients, feed and faeces were analysed for their gross energy and proximate compositions. In experiment 2, 18 weaner pigs were used in a completely randomised design for 63 days to determine the performance and cost analysis of feeding malted sorghum sprout at 0, 100 and 200 g/kg in pig’s diet, six pigs per diet with each pig representing a replicate. Daily feed intake and weekly weight gain were determined. The prevailing cost of each feed ingredient was used to compute the feed cost and, subsequently, the feed cost analysis. Results of digestibility trial showed that there was no difference in the utilisation of the chemical constituents of B?+?MSP and B?+?AA?+?MSP diets, which were also similar to the basal diet, except the crude protein (CP) in amino acid-supplemented malted sorghum sprout diet, which was lower compared to the basal diet. B?+?FMSP was lower (P?<?0.05) in the digestibility of dry matter, organic matter and CP compared to the basal diet. The digestible energy (DE) and the fraction of gross energy utilised as DE of each diet also were not affected by fermentation and supplementation with AA. In experiment 2, the levels of MSP used did not affect (P?>?0.05) the performance and feed cost indices measured. It was concluded that MSP can be used in growing pig’s diet, without the need for fermentation and AA supplementation, at 200 g/kg level with no adverse effect on the nutritive value of the diet.  相似文献   
2.
Thirty-two Ross 308 male broiler chickens were used in a precision feeding assay to investigate the effect of exogenous phytase (EC 3.1.3.26) on dietary apparent metabolisable energy (AME), dry matter digestibility (DMD) coefficient, nitrogen (NR), amino acid and mineral retentions. The excretion of endogenous losses measured as sialic acid (SA) was also determined. Four dietary treatments (control (C), C + 250 FTU (phytase units per kg feed), C + 500 FTU, and C + 2500 FTU) were studied with each treatment replicated eight times in randomised complete block design. Diets were formulated to be nutritionally adequate with the exception of available P content (2.3 g/kg non-phytate P). Over the 48-h collection period, the phytase fed birds retained 29.3 mg more Na and 2.3 mg more Zn (p < 0.05) than the control fed birds, with the relationship between phytase dose and Na and Zn retention being best described by a linear function (p < 0.05 and p < 0.001, for Na and Zn, respectively). Phytase supplementation did not have an effect on dietary AME, DMD and NR. However, increasing the dose of phytase led to a linear increase in dietary amino acid retention (p < 0.05). Dietary phytase decreased total sialic acid excretion in a linear fashion (p < 0.05). It can be concluded that supplementary phytase increases the retention (reduces the excretion) of dietary Zn and Na in broiler chickens. The beneficial effects of the addition of exogenous phytases to poultry diets seems to be mediated through improved dietary nutrients absorption and reduced endogenous losses.  相似文献   
3.
Low soil nitrogen limits maize (Zea mays L.) production in the West and Central African subregion. Levels of residual genetic variability were determined in two low‐N populations using selfed progeny evaluations, and results obtained indicate large genotypic and phenotypic variances for grain yield under both low‐ and high‐N environments for effective selection, while heritability estimates were generally low. Ear aspect and stay green were the most important traits contributing to grain yield for both populations. Selection reduced days to flowering, ASI and ear aspect, but increased plant height and yield. Yield gains of more than 25% occurred for the two populations under both low and high N with the most significant change of 42% occurring in one population under high N.  相似文献   
4.
进行肉鸡生长试验,旨在比较不同浓度的大肠杆菌源植酸酶对其生产性能,表观代谢能(AME)、氮(N)、氨基酸和矿物质的代谢率,唾液酸代谢以及绒毛形态学的影响。选择480只1日龄雌性罗斯308肉鸡,地面图养至28日龄。试验鸡分两阶段饲养,分别饲喂除磷外营养完全的育雏饲粮(1-21日龄)和育成饲粮(21~28日龄);其有效磷分别为28、23g·kg^-1。采用王米-豆粕型饲粮,分别添加植酸酶0、250、500和2500FTU·kg^-1.在21~28日龄间,从每个地面栏中选择2只放到代谢笼中(每笼2只)。在饲养阶段的最后两天,记录采食量,并收集粪便。采用全收粪法,测定AME、N、氨基酸和矿物质代谢率系数及内源损失。随着植酸酶浓度的升高,采食量和增重线性增加,与采食低磷饲粮组相比,平均增加11.7%和13.5%。与添加植酸酶500FTU·kg^-1组肉鸡相比,添加2500FTU·kg^-1组肉鸡体重提高66%,饲粮转化效率(FCE)提高2.4%。酶添加剂使AME摄入量提高10.3%,使代谢氮摄入量升高3.9%,这是通过提高采食量来实现的。与对照组相比,酶添加剂改善了肉鸡代谢性氨基酸和磷的摄入量,其分别提高14%和12.4%。酶添加剂对肉鸡回肠绒毛形态学没有显著影响。  相似文献   
5.
1. A total of 200 male Ross 308 chickens were used to evaluate the effects of a standardised combination of essential oils including 5% carvacrol, 3% cinnamaldehyde and 2% capsicum oleoresin (XT 6930; Pancosma S.A., Geneva, Switzerland) on their performance, hepatic antioxidant concentration and caecal tonsils morphometry.

2. Two diets were offered to broiler chickens from d old to 21 d of age. The control diet (C) was slightly lower in metabolisable energy (12.13 MJ/kg ME) and crude protein (215 g/kg CP) than breeders’ recommendation. The second diet, made as XT 6930, was added on the top of the control diet at 100 mg/kg. Each diet was offered ad libitum to birds housed in one of 10 floor pens in a randomised complete block design. The birds were housed in 20 floor pens, 10 birds in each pen, and were allocated to 10 replicates of the two dietary treatments.

3. The concentration of antioxidants in the liver of the birds was determined using high-performance liquid chromatography (HPLC) at 21 d of age. Birds fed control diet only had lower weight and converted less efficiently feed to gain compared to birds fed essential oils-supplemented diet. Feed consumption was not affected by dietary treatments. The antioxidant data showed that supplemented essential oils improved the hepatic concentration of carotenoids and coenzyme Q10 when fed to broiler chickens. The morphometry of the caecal tonsils of the birds was not influenced by dietary treatments.

4. It can be concluded that that dietary combination of essential oils, including carvacrol, cinnamaldehyde and capsicum oleoresin, improved growth, feed efficiency and the hepatic concentration of carotenoids and coenzyme Q10 when fed to broiler chickens.  相似文献   

6.
The nutritive value of leaves of four varieties of cassava - MS 6, TMS 30555, Idileruwa and TMS 30572 was evaluated based on their chemical composition and in vitro fermentation. Crude protein (CP) contents of cassava leaves ranged from 177 to 240 g/kg dry matter (DM), with TMS 30555 showing the highest CP contents. Neutral detergent fibre (NDFom) and acid detergent fibre (ADFom) contents of cassava leaves ranged from 596 to 662 and 418 to 546 g/kg DM respectively. Condensed tannin (CT) and hydrocyanic acid contents ranged from 1.0 to 3.8 g/kg and 58.5 to 86.7 mg/kg DM respectively. The range of volatile fatty acids (VFA) in the supernatant after in vitro incubation of the cassava varieties was: acetate (14.7-31.5 mmol/l); propionate (4.5-6.3 mmol/l); butyrate (3.1-3.9 mmol/l); valerate (0.4-0.6 mmol/l); iso-butyrate (0.6-1.3 mmol/l); iso-valerate (1.1-1.9 mmol/l). The acetate:propionate ratio resulting from fermentation of TMS 30555 was higher(p < 0.05) than that of the other leaves. The highest in vitro gas production of 50.5 ml/200 mg DM was recorded for MS6 being higher (p < 0.05) than for TMS 30572, but similar to TMS 30555 and Idileruwa. The DM, CP, ADF and HCN contents of cassava leaves were positively correlated with gas production, while CT content was negatively correlated with gas production. The study showed that leaves of the varieties MS 6 and TMS 30555 are superior to the others in terms of CP and gas production indicating a higher digestibility and energy content and thus nutritive potential. They may therefore serve as supplements for ruminants fed on poor roughages.  相似文献   
7.
1. A broiler growth study was conducted to compare the effect of different concentrations of an Escherichia coli-derived phytase on performance, apparent metabolisable energy (AME), nitrogen (N), amino acid and mineral metabolisability, sialic acid excretion and villus morphology when fed to broiler chickens. 2. Female Ross 308 broilers (480) were reared in floor pens from 0 to 28 d of age. All birds were fed on nutritionally complete starter (0 to 21 d of age) and grower diets (21 to 28 d of age) with the exception that they were low in P (28 and 23 g/kg available P, respectively). These maize-soy diets were supplemented with 0, 250, 500 or 2500 phytase units (FTU)/kg feed. 3. Between 21 and 28 d of age, two birds from each floor pen were selected, and each pair placed in one of 32 metabolism cages (two birds per cage). Feed intake was recorded and excreta collected for the last 2 d of the feeding period, and AME, N, amino acid and mineral metabolisability coefficients and endogenous losses were determined following a total collection procedure. 4. Feed intake and weight gain increased in a linear manner in response to phytase dose, with an average increase of approximately 11.7 and 13.5%, respectively, compared with chickens fed on the low-P diet. Birds given diets with 2500 FTU weighed 6.6% more and had a 2.4% higher feed conversion efficiency (FCE) than those fed on diets containing 500 FTU. 5. Enzyme supplementation increased the intake of AME and metabolisable N by 10.3 and 3.9%, respectively, principally through increases in feed intake. Birds given enzyme-supplemented diets also improved their intake of metabolisable amino acids and P by approximately 14 and 12.4%, respectively, compared with birds fed on the control diet. Enzyme supplementation did not affect ileal villus morphometry of the birds.  相似文献   
8.
1. A 56-d experiment was conducted to study the comparative influence of organic and inorganic dietary copper (Cu) sources on growth, blood characteristics and copper accumulation in organs of broilers. 2. A total of 480 Arbor-Acre unsexed broilers were fed on diets containing copper sulphate (CuSO(4)) or copper proteinate (Cu Pro) at concentrations of 50, 100 or 150 mg/kg of Cu supplementation. The birds were given a broiler starter diet from 1-28 d and a broiler finisher diet from 29-56 d which contained 30·8 mg/kg and 41·1 mg/kg basal copper concentration respectively. Growth performance, blood characteristics and Cu accumulation in organs of the broilers were measured. 3. At 28 d, Cu Pro-fed birds had improved feed conversion ratio compared with CuSO(4). At 56 d, birds fed on Cu Pro diets had significantly greater body weight than CuSO(4)-fed birds. Birds fed on CuSO(4) supplemented diets had significantly better feed conversion efficiency. Feed consumptions for the two Cu sources were not significantly different. At no stage did the concentration of added Cu affect the productive traits measured. 4. Cu Pro supplementation increased haemoglobin concentration but reduced plasma triglyceride and plasma cholesterol. Plasma cholesterol decreased as Cu concentration increased. 5. There was a greater accumulation of Cu in the blood, heart, lung, liver and bone of broilers fed on Cu Pro than in those receiving CuSO(4). The liver Cu concentration increased as dietary Cu concentration increased. 6. Cu Pro was more effective in promoting growth and reducing blood cholesterol, and was more bio-available in the organs of broilers.  相似文献   
9.
Sixteen West African dwarf goats weighing 5.0–5.6 kg were used in an experiment that lasted 112 days to investigate the utilization of citrus pulp based diets and E. cyclocarpum. A control diet which contained 88.5% dried brewers' grains (DBG) and other three experimental diets in which DBG was replaced with dried citrus pulp (DCP) at 25, 50 and 75% levels, respectively constituted the four treatments. The goats were divided into four groups of four animals each to balance for variation in live weight before they were assigned to the four different experimental diets. Significant differences (P < 0.05) were obtained in growth rate with (22.14–34.02 g/d) the highest and lowest value from 50 and 75% DCP inclusion respectively. The digestibility coefficients of DM, Ash, NFE, NDF, ADL, cellulose and hemicellulose increased with increasing levels of dried citrus pulp in the diets and were highest at 75% level of replacement. However, the CP digestibility of 83.85% was highest in the control diet and was significantly (P < 0.05) different from other diets containing citrus pulp. Nitrogen intake (g/d) decreased significantly (P < 0.05) with increasing levels of dried citrus pulp in the diets from 45.57–33.28 and was lowest in the control diet. Nitrogen balance also followed the same trend, being highest (42.07 g/d) at 25% DCP and lowest at 75% DCP. The Packed cell volume (PCV), haemoglobin concentration (Hb), red blood cells (RBC), white blood cells (WBC) and total blood protein (TBP) were significantly (P < 0.05) different across the dietary treatments at the start and end of the trial. The values for PCV, RBC, MCH, glucose and total protein decreased slightly in the control diet. Serum glutamate pyruvate transaminase (SGPT) values also increased significantly (P < 0.05) with increasing levels of dried citrus pulp in the diets at the end of the experiment and were highest (6.50 IU/L) at 75% level of citrus pulp. Therefore, the efficient utilization of citrus pulp and E. cyclocarpum by WAD goats was attained at the 50% level of inclusion in the diets.  相似文献   
10.
1. A precision feeding study was conducted to determine the metabolisable energy and amino acid digestibility in broilers fed on malted sorghum sprouts (MSP) supplemented with polyethylene glycol (PEG), charcoal (CH), phytase and xylanase. 2. A total of 64 male Ross broilers housed individually (8 replicates per treatment) were fed 30 g of the feedstuff as follows by gavage: MSP, MSP+1 g PEG/kg, MSP+10 g PEG/kg, MSP+1 g CH/kg, MSP+10 g CH/kg, MSP+3600 IU of evolved E. coli phytase/kg (EC 3.1.3.26) and MSP+1600 IU of bacterial xylanase/kg (EC 3.2.1.8). Another group of birds was used for the assessment of endogenous loss and they were provided with 50 ml glucose solution each by gavage. 3. True dry matter digestibility (TDMD), true nitrogen retention (TNR), total tract digestibility of apparent and true metabolisable energy (AME and TME) and amino acid (AAD and TAAD) were determined. 4. MSP contained 244.4, 24.0, 74.9 and 224.0 g/kg of crude protein, ether extract, ash and neutral detergent fibre, respectively. The total tannin content of the product was 140 g/kg and 99% of this was bound. 5. The various dietary treatments did not significantly affect the TDMD, TNR, AME and TME of MSP. The low values (0.471 g/g, -0.164 g/g, 6.15 MJ/kg and 9.31 MJ/kg, respectively) for the above measurements depicted the low feeding value of un-supplemented MSP for poultry. Also, PEG, CH and enzymes did not improve the AAD and TAAD of MSP for poultry. 6. It was concluded that the tannin content of MSP is high and it appeared to be bound with other nutrients thereby reducing their availability. This may explain its low AME and amino acid digestibility and the lack of effect of the various treatments for poultry.  相似文献   
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