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1.
The effects of supplementation with nitrogenous compounds on intake, digestibility, and microbial protein synthesis in cattle fed low-quality tropical forage were assessed. Five rumen fistulated crossbred Holstein × Gir heifers were used, with initial average live weight of 180 ± 21 kg. Signal grass (Brachiaria decumbens) hay (48.6 g kg−1 of crude protein (CP), on a dry matter (DM) basis) was used as roughage. Five treatments were defined according to nitrogen supplementation level (0, 20, 40, 60, and 80 g of CP kg−1 above the CP level of the hay). A mixture of urea, ammonium sulfate, and albumin at the ratios of 4.5:0.5:1.0, respectively, was used as nitrogen source. The experiment consisted of five experimental periods, according to a 5 × 5 Latin square design. The average CP contents in the diets were 51.9, 71.1, 86.0, 116.7, and 130.2 g kg−1, on a DM basis. A quadratic effect was detected (P < 0.10) of the CP levels in the diets on DM and neutral detergent fiber intake (kg/day), with maximum response at the levels of 102.4 and 100.5 g CP kg−1 DM, respectively. The average daily concentration of rumen ammonia nitrogen showed increasing linear pattern (P < 0.01) as function of CP levels in the diet, with estimated value of 9.64 mg dL−1 equivalent to the maximum DM intake. Microbial nitrogen flow in the intestine was linearly and positively related (P < 0.01) with the CP levels in the diet.  相似文献   

2.
The nutritive value of leaves of four varieties of cassava (MS 6, TMS 30555, Idileruwa and TMS 30572) were studied through analysis of their chemical components and degradability of their dry matter (DM) and crude protein (CP) in the rumen of sheep. Results of the chemical analyses showed that the leaves of the four varieties contained different proportions of organic matter which was significantly (P < 0.05) highest in TMS 30572 with value of 935 g/kg DM, while CP (gramme per kilogramme DM) was significantly highest in TMS 30555 (240), followed by MS 6 (235), TMS 30572 (208) and least in Idileruwa (177). Mean metabolisable energy (megajoules per kilogramme DM) was significantly (P < 0.05) highest in TMS 30572 (8.2) and similar with Idileruwa (8.0) but different from TMS 30555 and MS 6, respectively (7.8 and 7.6). The mineral contents (gramme per kilogramme DM) showed that leaves of MS 6 and Idileruwa had the highest concentrations of K (2.86) and a significantly lowest value (1.83) in TMS 30555. Also, the highest concentration of Ca and Fe (6.81 and 6.23) was recorded in MS 6. The highest Ca:P of 3.20 was obtained in TMS 30555. DM degradation characteristics and effective degradability varied significantly (P < 0.05) and were consistently highest in TMS 30572. The washing loss (a) ranged from 15.9% in MS 6 to 21.3% in TMS 30572. TMS 30572 tended to have higher (P = 0.546) insoluble but fermentable fraction (b) than all other varieties. Moreover, the potential degradability (a + b) tended to be higher (P = 0.041) in TMS 30572 (69.5%) followed by TMS 30555 (67.1%) and the lowest was in Idileruwa (42.7%). The highest effective degradability was recorded in TMS 30572 (63.9%) and the lowest in Idileruwa (40.7%). The degradation rate constants (c) of Idileruwa was significantly higher (P = 0.001) than those of MS6, TMS 30555 and TMS 30572. The results generally indicated that the leaves could be ranked for their potential feeding value as TMS 30572 (71.5%) > MS6 (65.8%) > Idileruwa (63.0%) > TMS 30555 (50.4%). It is therefore concluded from this study that leaves of TMS 30572 and MS 6 have good potential as feed resources for ruminant animals and could be used in ruminant feeding as protein source ingredient.  相似文献   

3.
This study was conducted to determine the amino acid profiles and rumen degradability of amino acids of three cultivated forage legumes – velvet bean (Mucuna pruriens), cowpea (Vigna unguiculata) and silverleaf desmodium (Desmodium uncinatum) – using the in situ nylon-bag technique. Two Friesian cows fitted with 10-cm-diameter rumen cannulae on a complete dairy feed ration (19% crude-protein dairy meal and maize silage) were used. Silverleaf desmodium had significantly (p < 0.05) higher concentration of amino acids compared with cowpea and velvet bean. Aspartic acid showed the highest (p < 0.05) concentration in all legumes and cysteine showed the lowest concentration. Legume forage of cowpea showed the highest (p < 0.05) level of degradability of amino acid followed by silverleaf desmodium and then velvet bean. Readily and slowly degradable components in all amino acids were highest (p < 0.05) in cowpea followed by silverleaf desmodium and then velvet bean. Moreover, silverleaf and cowpea showed higher (p < 0.05) levels of effective degradability of amino acids (at outflow rates p = 0.02, 0.04 and 0.06 h?1) than velvet bean. Total amino acid disappearance was the least in velvet bean, which suggests that it can be used to supply bypass protein to the duodenum of the ruminant animal.  相似文献   

4.
The objective was to estimate—according to the French feeding system—the nutritive value of three tropical grasses (Eragrostis olivacea, Setaria sphacelata and Tripsacum laxum) used in traditional small farms of Burundi. Dry matter (DM) yield was monitored on anti-erosive hedges or on small fields in 60 small farms for eight consecutive years. DM intake and digestibility values were measured on seven steers or seven male sheep. Degradability values were determined on three sheep. S. sphacelata exhibited higher DM yield (t ha−1), energy (UF, kg−1 DM) and protein (PDI, g kg−1 DM) values (17.3, 0.73 and 68, respectively) than T. laxum (9.11, 0.64 and 47) and E. olivacea (not determined, 0.46 and 42). The UF and PDI intakes of these grass species were able to meet only 51% to 92% of the energy and 59% to 133% of the protein requirements for maintenance of the experimental animals.  相似文献   

5.
We examined the in vitro fermentation characteristics and in situ dry matter (DM) and crude protein (CP) degradability of tamarind kernel powder extract residue (TKPER), a by‐product of polysaccharides thickener processing. Two types of TKPER (I and II), of which the CP and neutral detergent fiber organic matter basis contents (%) were 41.4 and 42.0 and 1.4 and 0.5, respectively, were compared with dry heat soybean (SB), soybean meal (SBM) and dry soybean curd residue (SBCR). The TKPERs had significantly lower in vitro gas production compared to the other products at each observation time (P < 0.05). The in vitro DM and CP digestibility (%) of TKPER I and II were 67.7 and 64.9, and 64.5 and 58.0, respectively, significantly lower than those of SB and SBM (P < 0.05). We used four wethers (55.6 ± 4.6 kg) with ruminal cannulas to investigate the in situ degradability of TKPER I, SB, SBM and SBCR. At the ruminal outflow rate of 0.05/h, the effective degradability (%) values of the DM and CP of TKPER I were 64.1 and 49.7, respectively, which were similar to those of SBM. In conclusion, TKPER had high CP and exhibited in situ degradability similar to that of SBM, suggesting that TKPER could be used as a protein source feed.  相似文献   

6.
Bindelle, J., Ilunga, Y., Delacollette, M., Muland Kayij, M., Umba di M’Balu, J., Kindele, E. and Buldgen, A. Voluntary intake, chemical composition and in vitro digestibility of fresh forages fed to Guinea pigs in periurban rearing systems of Kinshasa (Democratic Republic of Congo). Tropical Animal Health and Production. The daily voluntary intake (DVI) of Guinea pigs (GP) fed 15 fresh forages used in periurban rearing systems of Kinshasa (Democratic Republic of Congo) was investigated. In order to determine the best forages combination for GP diet, DVI was compared to their nutritional value measured in vitro using 1) a pepsin-pancreatin hydrolysis, 2) an gas fermentation test on the hydrolysed residues with an inoculum prepared from GP faeces, and 3) the chemical composition of the offered feeds and the hydrolysis residues. The forages ranking based on the DVI was correlated to the NDF content, but not to their nutritional values determined in vitro. According to their high DVI (from 4.23 to 7.75 g/kg liveweigth), and their valuable in vitro nutritional values (crude protein ranging from 261 to 279 g crude protein kg−1DM, pepsin-pancreatin digestibilities of the dry matter from 0.55 to 0.59 and final gas production from 170 to 196 l kg−1DM), Desmodium intortum, Euphorbia heterophylla or Amaranthus hybridus, can be suggested to the farmers to complement the usual diet distributed to the GP based on Panicum maximum.  相似文献   

7.
Microbial fermentation of non-digestible carbohydrates in the pig's large intestine induces a shift of N excretion from urea in urine to bacterial protein in faeces. Experiments were carried out to measure the mineral N incorporation by the pig intestinal microflora using 5 purified carbohydrates in a gas-test: starch (S), cellulose (C), inulin (I), pectin (P) and xylan (X). Fermentation kinetics was modelled. N source in the buffer solution was replaced by 15N labelled NH4Cl. The bacterial N fixation was determined at mid-fermentation, measuring 15N incorporation into the solid phase of the buffer. The bacterial N fixation was higher (P < 0.001) with I and S (19.9 and 18.1 mg N/g incubated DM), compared to P, C and X (8.7, 5.9 and 5.5 respectively). Inulin and S were fermented also more rapidly, even if I (0.081 h− 1) and C (0.074 h− 1) showed lower half time fractional rate of degradation than S (0.153 h− 1), P (0.133 h− 1) and X (0.104 h− 1). The insoluble dietary fibre content of the substrates was negatively correlated to bacterial N fixation (r = − 0.957, P = 0.011). The high crude protein content of P (32.5 mg g− 1DM) might explain the lower impact of this substrate on bacterial N fixation, despite its rapid fermentation. Beside the proportion of insoluble fibre, the N content and the rate of fermentation seem to be the major factors influencing bacterial protein synthesis. Further studies including ingredients with variable content of indigestible protein and mean retention time in the pig's intestines are necessary.  相似文献   

8.
The aim of this study was to evaluate the animal performance of late lactating grazing dairy cows in response to fresh chopped maize (FCM) supplementation under a small farming system. Twenty-four multiparous Holstein dairy cows were used in a rotational grazing on a mixed alfalfa–orchard grass sward. Three treatments were evaluated: 0, 4, and 8 kg dry matter (DM) of FCM cow−1 day−1. The experimental design was a crossover, with three periods lasting 19 days each. There were no differences on individual milk production nor on milk composition. Herbage DM intake decreased (P < 0.0001) from 8.4 to 5.2 and 3.1 kg DM when increasing FCM from 0 to 4 and 8 kg DM, respectively. Total DM intake increased (P < 0.0001) with 8 kg DM of FCM, averaging 14.8 kg. Substitution rate was 0.75 and 0.67 kg of pasture per kilogram of FCM with 4 and 8 kg DM of FCM, respectively. Consequently, stocking rate (STR) increased (P < 0.0001) from 3.8 to 6.2 and 8.8 cows ha−1, and milk production per hectare increased (P < 0.0001) from 39.3 to 64.5 and 95.5 kg of milk, with 0, 4, and 8 kg DM of FCM, respectively. This means that STR increases 0.63 cows ha−1, and 0.75 kg of milk ha−1 when FCM is increased in 1 kg of DM. In conclusion, offering FCM as supplement to grazing dairy cows in their final lactation stage had no benefits in individual milk production or milk composition, but had benefits on milk production per hectare.  相似文献   

9.
An experiment was conducted to evaluate the performance of crossbred growing chickens (Rhode Island Red × indigenous Burkina Faso hens) from 6 to 17 weeks of age, under five feeding/management regimes: (1) CMx(+), confined and given a mixed feed containing cracked maize and cowpea and a vitamin–mineral premix ad libitum; (2) CS(+), confined and offered ad libitum a choice of cracked maize and cowpea with the premix; (3) ScS(+), scavenging from 09:00 to 16:00 with the diet in treatment (2) available from 16:00 to 09:00; (4) ScS(−), treatment (3) but without the premix; and (5) ScO, scavenging only, with no supplements provided. Daily dry matter (DM) intake was highest for CS(+) (43.5 g), and lowest for CMx(+) (33.6 g) (p < 0.05), with intermediate intakes for ScS(+) and Sc(−) of 36.7 g and 36.2 g, respectively. The ratios of intakes of cowpea to maize were 50:50, 21:79, 27:73 and 22:78 for CMx(+), CS(+), ScS(+) and ScS(−), respectively (p < 0.05). Dietary concentrations of crude protein (CP) were 15.7%, 11.5%, 12.3% and 11.6% of DM for CMx(+), CS(+), ScS(+) and ScS(−), respectively. Average daily gains (ADG) were 8.15 g, 5.24 g, 6.03 g, 5.36 g and 4.45 g for CMx(+), CS(+), ScS(+), ScS(−) and ScO, respectively, and were significantly higher for CMx(+) (p < 0.05). Feed conversion ratio was highest for CS(+) and lowest for CMx(+). ADG of the males (6.44 g) was significantly (p < 0.05) higher than that of the females (5.86 g). Breast and thigh muscle weights were highest for ScS(+) (p < 0.05).  相似文献   

10.
Diversity of chemical composition, in vivo digestibility and in situ dry matter degradability of oat hay (Avena sativa) were studied. Oat hay samples obtained from 22 batches imported were analyzed for chemical composition. The result showed a wide range of variations in crude protein (3.9–8.8%, on a dry matter basis), crude fiber (22.1–35.2%), nitrogen free extract (50.0–66.0%), organic cellular contents (23.4–40.0%), organic cell wall (53.1–70.8%), organic a (4.1–9.8%), organic b (49.0–63.8%) fractions and the estimated total digestible nutrients (50.3–63.8%) from the organic components. Of these, four oat hay samples were used for the measurement of dry matter intake, in vivo digestibility and in situ dry matter degradability in sheep. Significant differences were observed for the dry matter intake, in vivo digestibility of dry matter, crude protein, crude fiber and nitrogen free extract, dry matter disappearance at 48 h and effective degradability at k = 0.05 h?1 of the samples (P < 0.05). The results revealed a wide range of diversity of nutritional quality of the imported oat hay that could have an affect on production potential in animals.  相似文献   

11.
Fourteen days old Rhode Island Red chicks were used to evaluate effects of processed fish offal (fishmeal) on DM intake (DMI), body weight gain (BWG), feed conversion ratio (FCR = DMI/BWG) and carcass traits. Ten chicks were assigned to each of 3 replicates of 6 diets (T1, T2, T3, T4, T5, T6, containing 0, 3.32, 6.64, 9.96, 13.28 and 16.6% fishmeal, respectively, having 18.44–19.82% CP). After 77 days of ad-lib feeding, 3 male and 3 female chicks per treatment were fasted overnight, killed and body parts weighed. T1 had lowest but T6 highest (p ≤ 0.001) daily intakes of 68.5 and 77.0 g DM head−1, 13.3 and 14.8 g CP head−1 and 231 and 243 kcal ME head−1, respectively. BWG (10.7 g head−1 d−1), FCR (6.79), weights of carcass (569 g), breast (160 g) and total edible (676 g) and dressing % (66%) of T1 (0% fishmeal) was smaller (p ≤ 0.001) than those of fishmeal groups {12.8 to 13.5 g head−1 d−1; 5.83 to 6.35 g; 671 to 729 g; 196 to 219 g; 807 to 876 g and 67 to 68%, respectively}. Best results of BWG, FCR and carcass traits were obtained at 9.96% fishmeal inclusion level; however acceptable results could be obtained up to 12.5%.  相似文献   

12.
The study was conducted to determine the effect of supplementation with rice bran (RB) and /or noug seed (Guizotia abyssinica) meal (NSM) on feed intake, digestibility, and body weight (BW) change in hay based feeding of Farta sheep. Twenty five yearling Farta rams with a mean initial BW of 19.23 ± 0.28 kg were used in randomized complete block design arranged into five blocks of five animals. The five dietary treatments that consisted of hay alone (T1), hay + RB (T2), hay + mixture of RB and NSM at a ratio of 1:2 (T3), hay + mixture of RB and NSM at a ratio of 2:1 (T4) and hay + NSM (T5) were randomly assigned to each sheep within a block. The supplements were daily offered at 300 g dry matter (DM) head−1 in two equal parts at 800 and 1600 h. Supplementation improved the total DM and acid detergent fiber (ADF) intake (P < 0.05), organic matter (OM) intake (P < 0.01), crude protein (CP) intake (P < 0.001). The apparent digestibility of DM in T5 was higher (P < 0.05) than in T1 and T2 and that of T4 was also higher (P < 0.05) than in T1. The apparent digestibility of CP in T5 and T4 were higher (P < 0.001) than in T1 and T2 and that of T3 and T2 were also higher (P < 0.001) than for T1. The BW gain of experimental sheep was improved (P < 0.01) by supplementation with NSC (T5) and/or its mixtures with RB (T3 and T4). The results of the study showed that supplementation with either of both mixtures of NSM and RB at 43% of total DM intake promoted better feed intake, digestibility and BW gain in Farta sheep.  相似文献   

13.
The effect of decortication on chemical composition and degradability characteristics of four Danish oat varieties was investigated. Effective degradability (ED) and post-ruminal disappearance (PRD) were measured by in situ and mobile bag techniques respectively. Decorticated oat showed higher (p = .01) concentrations of crude protein (CP; 134 vs. 108 g/kg DM) and crude fat (71.6 vs. 53.1 g/kg DM) and a higher (p = .001) organic matter digestibility (OMD; 888 vs. 703 g/kg OM) than oat. The content of total fatty acids (FA) in DM was higher in decorticated oat. The proportion of linoleic acid (C18:2 n6) increased (p < .05) due to decortication, while the linolenic acid (C18:3 n3) proportion of total FA decreased in decorticated oat. Decortication increased (p = .01) the concentration of amino acids (AA), but the proportion of lysine in total AA decreased (p < .002). Effective degradability (ED) of both DM and CP was (p < .001) higher in decorticated oat. Decortication increased the total tract disappearance (TTD) and PRD of CP (p < .001). In conclusion, decortication can be used as a practical approach to increase the nutritional value of oat.  相似文献   

14.
Whole pod and seeds of velvet bean (Mucuna pruriens) were included in diets for growing sheep used to validate previously estimated ME values of 9.7 MJ and 12.6 MJ for whole pod and seed respectively. Twenty-four lambs, 15 females and nine males of 18.7 ± 2.4 kg average weight, were allocated in three treatments using a completely randomized block design with eight replicates per treatment. Each group was given a diet with a ratio of 60% of Napier grass (Pennisetum purpureum) and 40% of a supplement with the addition of 0%, 50% whole pod or 66% of M. pruriens seeds, for TI, TII and TIII respectively. Diets were formulated to meet the requirements for 100-g daily live weight gain (LWG). The total dry matter intake (836 g a−1 d−1, forage + supplement), LWG (90 g a−1 d−1) and feed conversion (9.66 kg DM/kg LWG) of lambs from TIII were lower (P < 0.05) compared to 941 g, 121 g, and 7.78 kg DM/kg LWG from TII and 976 g, 132 g and 7.50 kg DM/kg LWG from TI respectively. No difference was found (P > 0.05) between TI and TII in the three evaluated variables. The ME values of whole pod and seeds of M. pruriens used in this work were validated. It was concluded that M. pruriens can be included as a component in diets for growing sheep, as a partial replacement of conventional feedstuffs.  相似文献   

15.
The aim of the study was to determine the effect of feeding feed blocks containing varying proportion of urea-treated paddy straw (UTPS) on dry matter (DM) intake (DMI), nutrient utilization and N balance in Mithun. For the purpose, four adult male Mithun (279.5 ± 8.2 kg) were selected and offered four experimental rations viz. R1 (Napier fodder + concentrate at 60:40), R2 (UTPS + concentrate at 50:50), R3 (UTPS + concentrate at 60:40) and R4 (UTPS + concentrate at 70:30) in 4 × 4 Latin square design. The DMI % of body weight was 2.59, 2.96, 2.85 and 2.77 and the DMI g kg−1 W0.75 was 107, 123, 118 and 115 in Mithun fed R1, R2, R3 and R4, respectively. The mean DMI was (P < 0.01) higher in animals fed R2 and R3 than R1 and R4, whereas the water intake was (P < 0.01) higher in Mithun fed R2, R3 and R4 than R1. The digestibility of DM, organic matter, crude protein, crude fibre, neutral detergent fibre and cellulose were (P < 0.05) higher in animals fed R2, R3 and R4 than R1. A positive N balance was observed in all the experimental animals, with higher (P < 0.05) values among the animals offered R2, R3 and R4 than R1. The digestible crude protein and total digestible nutrient intakes were higher (P < 0.05) in Mithun fed R2 and R3 than R1 and R4. It is concluded that the UTPS can be incorporated up to 70% to formulate the complete feed/feed block and can be used for feeding of Mithun under complete confinement system.  相似文献   

16.
The pharmacokinetics and urinary excretion of gatifloxacin were investigated after a single intravenous injection of 4 mg/kg body weight in buffalo calves. The therapeutic plasma drug concentration was maintained for up to 12 h. Gatifloxacin rapidly distributed from blood to tissue compartments, which was evident from the high values of the distribution rate constant, α1 (11.1 ± 1.06 h−1) and the rate constant of transfer of drug from central to peripheral compartment, k 12 (6.29 ± 0.46 h−1). The area under the plasma drug concentration–time curve and apparent volume of distribution were 17.1 ± 0.63 (μg.h)/ml and 3.56 ± 0.95 L/kg, respectively. The elimination half-life (t 1/2 β), total body clearance (ClB) and the ratio of drug present in tissues and plasma (T/P) were 10.4 ± 2.47 h, 235.1 ± 8.47 ml/(kg.h) and 10.1 ± 2.25, respectively. About 19.7% of the administered drug was excreted in urine within 24 h. A satisfactory intravenous dosage regimen for gatifloxacin in buffalo calves would be 5.3 mg/kg at 24 h intervals. Abbreviations for pharmacokinetic parameters are given in the footnote of Table I  相似文献   

17.
The effects of adding crude glycerine with sodium monensin or essential oils to beef cattle diets on the intake, degradability of DM and nutrients, rumen concentration of volatile fatty acids (VFA) and in vitro gas production were evaluated. Five ruminally cannulated Nellore steers were randomly assigned to a 5 × 5 Latin square design. The treatments were as follows: CONT, without crude glycerine and additives; EO, with essential oils and without crude glycerine; MON, with sodium monensin and without crude glycerine; EOG, with essential oils and crude glycerine; MONG, with sodium monensin and crude glycerine. Treatments with essential oil and sodium monensin increased the NDF and STC intake and the DM degradability. When crude glycerine was combined with either sodium monensin or essential oil, there was a reduction in DM, NDF and STC intake and an increase in DM and CP degradability of the diets. The adding crude glycerine to essential oil diets reduced the CH4 production. Sodium monensin treatments reduced DM and NDF intake and the production of total gas, CH4, total VFA and acetic acid concentration. In conclusion, the adding crude glycerine (200 g/kg DM) with either sodium monensin (0.03 g/kg DM) or essential oil (0.5 g/kg DM) can be utilized in diets for Nellore cattle without causing detrimental effects on feed intake and improving the DM degradability.  相似文献   

18.
A study was conducted to estimate dry matter (DM) degradability in the rumen of lambs offered a basal soybean meal and sorghum grain diet with three levels of white mulberry (WM) leaves (Morus alba). Diets consisted of 90% concentrate and 10% sorghum straw, which was incrementally replaced by WM leaves at 0% (control diet, T1), 2.5% (T2), and 5% (T3) of the total ration. Crude protein (CP) in WM was 21.8% (DM basis). Diets had equal CP (14% DM basis) and metabolizable energy (10.8 MJ/kg DM) content. Three non-castrated Pelibuey male lambs fitted with permanent rumen cannula were utilized in a 3 × 3 Latin square design. Each experimental period consisted of 10 days of adaptation followed by sampling. DM degradability was determined using the nylon bag technique. Bags contained the experimental diets offered in each period and were incubated in rumen in pairs for 4, 8, 12, 24, and 48 h. The potential degradation was higher (P < 0.05) for T2, followed by T3 and T1. WM level did not influence the degradation rate or the effective degradation at the three passage rates modeled. It was concluded that WM forage may have useful application in feedlot diets for growing lambs, as this forage increases potential degradation of high-grain diets. The incorporation of WM in diets for feedlot lambs in tropics may reduce the use of expensive conventional protein supplements.  相似文献   

19.
Musa sp. peels are widely used by smallholders as complementary feeds for cattle in the tropics. A study of the influence of the variety and the maturation stage of the fruit on fermentability and metabolisable energy (ME) content of the peels was performed using banana (Yangambi Km5) and plantain (Big Ebanga) peels at three stages of maturation in an in vitro model of the rumen. Peel samples were analysed for starch, free sugars and fibre composition. Samples were incubated in the presence of rumen fluid. Kinetics of gas production were modelled, ME content was calculated using prediction equation and short-chain fatty acids production and molar ratio were measured after 72 h of fermentation. Final gas production was higher in plantain (269–339 ml g−1) compared to banana (237–328 ml g−1) and plantain exhibited higher ME contents (8.9–9.7 MJ/kg of dry matter, DM) compared to banana (7.7–8.8 MJ/kg of DM). Butyrate molar ratio decreased with maturity of the peels. The main influence of the variety and the stage of maturation on all fermentation parameters as well as ME contents of the peels was correlated to changes in the carbohydrate fraction of the peels, including starch and fibre.  相似文献   

20.
A study was conducted to assess the influence of genetic and environmental factors on Brown Swiss calf birth weight, and to estimate variance components, genetic parameters, and breeding values. Data were collected on 1,761 Brown Swiss calves born from 1990 to 2005 in the Konuklar State Farm in Turkey. Mean birth weight for all calves was 39.3 ± 0.09 kg. Least squares mean birth weights for male and female Brown Swiss calves were 40.3 ± 0.02 and 39.0 ± 0.02 kg, respectively. Variance components, genetic parameters, and breeding values for birth weight in Brown Swiss calves were estimated by restricted error maximum likelihood (REML)–best linear unbiased prediction(BLUP) procedures using an MTDFREML (multiple trait derivative free restricted maximum likelihood) program employing an animal model. Direct heritability (h d2), maternal heritability (h m2), total heritability (h T2), r am and c am estimates were 0.12, 0.09, 0.23, −0.58, and −0.06, respectively. The estimated maternal permanent environmental variance expressed as a proportion of the phenotypic variance (c 2) was 0.05. Breeding values were estimated for the trait and used to evaluate genetic trends across the time period investigated. The genetic trend linear regression was not different from zero. No genetic trend for birth weight was expected, since there had been no direct selection pressure on the trait. Absence of a trend confirms that there was no change due to selection pressure on correlated traits. Genetic and environmental parameter estimates were similar to literature values indicating that effective selection methods used in more developed improvement programs would be effective in Turkey as well.  相似文献   

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