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1家禽能量需要量 生长家禽的能量需要量。利用家禽的生长阶段有两个目的：一是生产商品肉仔禽;二是作为种用或蛋用家禽的育成期。对于生长家禽,随着周龄的增大,体重增加,体脂含量上升,因而其日粮中能量浓度应随周龄增长而相应提高。在一定程度上,生长家禽日粮能量水平与饲料转化率、生长速度及其胴体脂肪含量呈正相关。肉用仔鸡的生产周期仅5~6星期,这期间其体重是以4~5倍的速度增长的,要实现这样迅速的生长发育,主要是适时提高饲料中的能量水平,降低蛋白质水平,提高单位日粮营养素含量。据测定,每千克日粮的代谢能提高230千焦,则可使饲料转化率提高4%,一般常用油脂配制高能量日粮。但在提高能量水平的同时,应降低蛋白质水平,否则高能高蛋白的日粮容易导致较高的肉鸡腹水症、猝死症和痛风症等病的发生与死亡。蛋鸡的生长是前期快,后期慢。幼龄鸡的饲料能量用于维持生命的部分少,而用于生长的部分多。因此,饲料效率高,则要很好地利用这个阶段,让雏鸡成长快些。在14~20周龄,要求鸡不要贮存太多脂肪,延迟性成熟,使之晚些产蛋,为此要采取限制饲养法,供给低能量水平的饲料,即代谢能11.286兆焦/千克左右。 相似文献
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肉鸡的超快生长速度要求营养学家配制出更加优质的日粮,以充分发挥肉鸡的遗传潜力。
谷物是家禽日粮中的主要饲料原料,而其中玉米应用最为普遍,通常与其他蛋白饲料一起添加到饲料中,如豆粕,这通常会提高配合饲料的成本。玉米富含能量,纤维含量低,易于为大多数畜禽所消化。 相似文献
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1日粮能量、蛋白质与氨基酸水平生产上为了使肉鸡有较快的生长速度和较高的饲料利用率,通常采用油脂配制高能量日粮,但高能高蛋白日粮除导致腹水症、猝死症外,还容易导致较高的腿病发生率。为了满足家禽的生长需要而避免腿病的发生,日粮中蛋白质浓度应随周龄增加而下降,能量则要相应提高,即在生长期内,日粮能 相似文献
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家禽育种公司不断通过改变肉鸡的生理和代谢特性,来提高其生产性能。作为动物营养师和饲料配制者面临的艰巨任务是重新配制饲料,以满足不断改变的营养需要。由于饲料配方日益复杂,有关营养对生长速度、胴体组分和免疫力的影响研究资料正迅速增多。 除了遗传特性不断改变外,不同的饲养环境和管理条件也会影响肉鸡的日粮需要量。肉 相似文献
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在配制肉鸡日粮时，养殖户要充分了解各种成分的辩证关系，搞好合理搭配，力争配制出营养均衡、价格合适的配合饲料。
1能量与蛋白质之间的辩证关系
肉鸡摄取饲料首先是为了满足能量需求，当能量得到满足时即停止采食。如果日粮中能量不足，肉鸡采食量增加，既摄入过多蛋白质，超出营养需求，同时还会通过分解蛋白质满足对能量的需要，造成蛋白质浪费。 相似文献
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能量是肉鸡各种生命活动的基础,也是肉鸡饲料中价格占比最高的元素,主要源于日粮中碳水化合物、脂肪和蛋白质的化学能。准确评估肉鸡能量需要量和日粮成分能量水平在肉鸡营养和生产中具有重要的科研和经济价值。代谢能（ME）体系是目前用于家禽饲料原料能值评定的成熟体系,在家禽营养和配方中被广泛使用。但和净能（NE）体系相比,代谢能体系忽略了饲料中不同原料成分摄食和消化过程中的热增耗（HI）差异对原料能值评价的影响,降低了原料能值评定的准确性。因此,作者结合国内外肉鸡净能相关研究进展,重点就肉鸡净能测定方法、肉鸡原料净能预测方程和影响肉鸡净能体系应用因素等方面进行综述讨论,以期为净能体系在肉鸡生产中的应用提供参考。 相似文献
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日粮各营养素及各生长因子的平衡配制是家禽经济生产的关键因素.各国公布的肉鸡饲养标准不尽相同,各不同品种的肉用仔鸡的营养需要也不相同.以能量和蛋白质为例,上海大江公司的AA肉鸡0～3周、3～5周和6周～上市所列的需要分别为12.970MJ/kg和23.0%、13.389MJ/kg和20.5%、13.389MJ/kg和18.5%,英国罗斯308肉鸡分别为12.803～12.970MJ/kg和22.0～23.0%.12.887～13、221MJ/kg和20.0～21.0% 13.221～13.389MJ/kg和18.0～19.0%.近几年来,正大、大江、豫大等合资企业应运而生,并占领国内市场.随着家禽营养研究新的进展,我国在“六五”期间颁布的家禽营养需要标准已不能适应科研和生产发展的需要,为改进完全日粮品质,提高生产水平,促进上海乃至我国肉鸡业的发展,参照NRC(1984)肉鸡MB和CP标准,并结合我国肉鸡生产实际,开展肉鸡优化配方以确立肉鸡日粮中能量和蛋白质水平及恰当的比例的研究仍有着重要的意义. 相似文献
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Development of a model to predict dietary metabolizable energy from digestible energy in beef cattle
Seongwon Seo Kyewon Kang Seoyoung Jeon Mingyung Lee Sinyong Jeong Luis Tedeschi 《Journal of animal science》2021,99(7)
Understanding the utilization of feed energy is essential for precision feeding in beef cattle production. We aimed to assess whether predicting the metabolizable energy (ME) to digestible energy (DE) ratio (MDR), rather than a prediction of ME with DE, is feasible and to develop a model equation to predict MDR in beef cattle. We constructed a literature database based on published data. A meta-analysis was conducted with 306 means from 69 studies containing both dietary DE and ME concentrations measured by calorimetry to test whether exclusion of the y-intercept is adequate in the linear relationship between DE and ME. A random coefficient model with study as the random variable was used to develop equations to predict MDR in growing and finishing beef cattle. Routinely measured or calculated variables in the field (body weight, age, daily gain, intake, and dietary nutrient components) were chosen as explanatory variables. The developed equations were evaluated with other published equations. The no-intercept linear equation was found to represent the relationship between DE and ME more appropriately than the equation with a y-intercept. The y-intercept (−0.025 ± 0.0525) was not different from 0 (P = 0.638), and Akaike and Bayesian information criteria of the no-intercept model were smaller than those with the y-intercept. Within our growing and finishing cattle data, the animal’s physiological stage was not a significant variable affecting MDR after accounting for the study effect (P = 0.213). The mean (±SE) of MDR was 0.849 (±0.0063). The best equation for predicting MDR (n = 106 from 28 studies) was 0.9410 ( ± 0.02160) +0.0042 ( ± 0.00186) × DMI (kg) – 0.0017 ( ± 0.00024) × NDF(% DM) – 0.0022 ( ± 0.00084) × CP(% DM). We also presented a model with a positive coefficient for the ether extract (n = 80 from 22 studies). When using these equations, the observed ME was predicted with high precision (R2 = 0.92). The model accuracy was also high, as shown by the high concordance correlation coefficient (>0.95) and small root mean square error of prediction (RMSEP), <5% of the observed mean. Moreover, a significant portion of the RMSEP was due to random bias (> 93%), without mean or slope bias (P > 0.05). We concluded that dietary ME in beef cattle could be accurately estimated from dietary DE and its conversion factor, MDR, predicted by the dry matter intake and concentration of several dietary nutrients, using the 2 equations developed in this study. 相似文献
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Nishchal K. Sharma Zhibin Ban Hank L. Classen Huaming Yang Xiaogang Yan Mingan Choct Shu-Biao Wu 《动物营养（英文）》2021,7(2):506
Pea starch consists predominantly of C-type of amylopectin chain which is more resistant to digestive enzymes than A-type of starch thus slowly digested in poultry. It was hypothesized that the presence of slowly digested pea starch in broiler diets will increase net energy and the efficiency of energy utilization in broilers. Two experiments were performed to investigate starch digestibility of pea at different incubation times (in vitro study) and the effect of dietary pea on heat increment and net energy in broilers using an open-circuit respiratory calorimetry system (in vivo study). One-day-old Ross 308 male broilers were fed a common starter crumble from d 1 to 10 and standard grower diets thereafter. At d 21, birds were transferred to the chambers each housing 2 birds. Each treatment was replicated 6 times with 2 identical runs of 3 replicates per treatment. A wheat-soybean meal-based diet was used as a control and the treatment diet contained 500 g of pea/kg pea. In vitro study showed that pellet processing increased (P < 0.001) starch digestibility, particularly at shorter times for wheat and a much larger response for pea. Birds offered the pea-based diet had lower (P = 0.002) feed intake, lower (P = 0.020) body weight gain, but a similar (P > 0.05) FCR compared to those offered the wheat-based diet. Net energy (NE) and apparent metabolizable energy (AME) values were higher in the pea-based diet than in the wheat-based diet (P = 0.037 for NE and P = 0.018 for AME). Heat production, respiratory quotient, heat increment of feed, efficiency of utilization of gross energy for AME, and efficiency of utilization of AME for NE did not differ (P > 0.05) between the 2 treatments. There was no effect (P > 0.05) of pea on the total tract digestibilities of dry matter, crude protein and ash, but the total tract digestibility of starch was higher (P = 0.022) in the pea-based diet compared to the wheat-based diet. This study provides insight into the energy metabolism of broilers offered a pea-based diet and indicates that dietary pea supplementation increases dietary AME and NE but has no effect on heat increment of feed and the efficiency of energy utilization in broilers. 相似文献
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Effect of dietary net energy concentration on dry matter intake and energy partition in cows in mid‐lactation under heat stress 
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下载免费PDF全文 Fangquan Yan Bai Xue Liangrong Song Dalecuo Jun Xiao Siyan Ding Xiaofei Hu Dengpan Bu Tianhai Yan 《Animal Science Journal》2016,87(11):1352-1362
This study aimed to determine the net energy requirement of Holstein cows in mid‐lactation under heat stress. Twenty‐five multiparous Holstein cows were randomly allocated to five groups corresponding to five isonitrogenous total mixed rations, with net energy for lactation (NEL) content of 6.15 (NE‐6.15), 6.36 (NE‐6.36), 6.64 (NE‐6.64), 6.95 (NE‐6.95), 7.36 (NE‐7.36) MJ/kg of dry matter (DM), respectively. Throughout the experimental period the average temperature humidity index at 07.00, 14.00 and 22.00 hours was 72.1, 88.7, and 77.6, respectively. DM intake decreased significantly with the elevated dietary NEL concentration. Fat corrected milk increased quadratically, and milk fat content and milk energy (MJ/kg) reached the greatest in the NE‐6.95 group with increasing dietary NEL content. Strong correlations were found between dietary NEL content and: (i) DM intake; (ii) NEL intake; (iii) milk energy (El); (iv) El/metabolizable energy intake (MEI); (v) El/NEL intake, as well as between NEL intake and fat corrected milk yield (FCM). The suitable net energy required for dairy cows producing 1 kg FCM ranged from 5.01 to 5.03 MJ, was concluded from the above‐stated regressions. Correlation between heat production (HP) and MEI could be expressed as: Log (HP) = ?0.4304 + 0.2963*MEI (n = 15, R2 = 0.99, Root Mean Square Error (RMSE) = 0.18). Fasting HP was 0.3712 MJ/kg0.75 when extrapolating MEI to zero. 相似文献
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B. Wichert A. Liesegang S. Hartnack 《Journal of animal physiology and animal nutrition》2014,98(4):628-635
Urinary energy losses in cats have to be determined in energy balance trials as well as for the calculation of the metabolizable energy (ME) content of cat food. The aim of the present study was: first, to assess whether the energy content of cat urine quantified by bomb calorimetry differs from that quantified using GE (kJ) urine = 33 kJ × g C urine + 9 kJ × g N urine and investigate whether this difference could be attributed to influences of diets. Second, to assess whether the subtraction of 3.1 kJ/g of protein intake used for estimation of metabolizable energy content of cat foods is confirmed as usable. Data from 27 energy and protein balance trials from different studies with complete sampling of urine and faeces (29 cats in part A and 35 cats in part B) were used. Gross energy, carbon and nitrogen were determined in food, faeces and urine. Gross energy values in urine tended to be higher when determined with the formula of Hoffman and Klein compared to bomb calorimetry. The average relative difference of gross energy values between the methods was 18.8%. The mean energy loss in kJ/g of protein intake resulted in 3.7 kJ/g protein intake, which was not statistically significantly different (p = 0.12) from the tested value of 3.1 kJ/g of protein intake. In conclusion, the formula of Hoffman and Klein is not appropriate for the estimation of energy in cat urine. In balance studies, it is advisable to quantify the urinary energy content by bomb calorimetry. In the second part of the study, the protein correction factor to determine ME of 3.1 kJ/g protein intake for urinary energy losses of Kienzle et al. could be confirmed. 相似文献
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Carmen Klein Melanie Thes Linda F. Bswald Ellen Kienzle 《Journal of animal physiology and animal nutrition》2019,103(6):1952-1958
The correct assumption of metabolisable energy (ME) requirement is essential for the nutrition consultation and diet formulation. In young dogs, too high energy supply can accelerate growth and thus lead to developmental orthopaedic diseases. The aim of the present study was to collect the data on ME intake and body weight (BW) development in privately owned growing dogs in order to compare these data with the current recommendations. Our hypothesis was that the actual ME intake of healthy young dogs would be lower than the actual recommendation. The data of 493 privately owned puppies (median age at first consultation 21 weeks, the median expected mature BW 30 kg) on ME intake, actual and expected mature BW were collected and compared with recommendations of the Society of Nutrition Physiology (GfE, Meyer and Zentek and NRC). In 243 dogs, there was a follow‐up. The actual BW did not deviate systematically from the calculated expected BW (R2 = .929). The ME intake significantly decreased with age (p < .05) and significantly increased with expected mature BW (p < .05). There was no significant interaction between these two parameters (p > .05). Sex had no effect on the ME intake (p > .05). The ME intake of young dogs with a history of skeletal problems or of food allergy did not differ systematically from healthy dogs of similar age and expected mature BW. The ME intake was considerably below NRC recommendations, especially in younger puppies (>8–17 weeks: 78%, >17–26 weeks: 83% of NRC recommendation). A predictive linear equation for ME intake was developed: ME intake (MJ) = (1.063 ? 0.565 × [actual BW/expected mature BW]) × actual BW0.75. 相似文献
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甘肃河西地区农田生态系统能量投入产出及效率分析 总被引：9，自引：4，他引：5
应用生态学能流研究方法 ,对河西 4 5年农田系统能量输入输出及效率进行了力能学分析。结果表明 ,总投能逐年增加 ,1994年总投能最高的县为张掖市 (131.5 9× 10 3MJ/ hm2 )。无机能在总投能中所占比例依次呈现出平稳、快速、缓慢增长的变化趋势 ,天祝县无机能投入远远低于其它县市 ,1994年为总投能的 18%。总产能呈现出递增趋势 ,但自 2 0世纪 80年代中期以后增长缓慢 ,4 5年来不同县市总产能增加以酒泉市和张掖市最大 ,1994年酒泉市和张掖市总产能分别为2 35 .93× 10 3和 2 32 .38× 10 3MJ/ hm2 。 4 5年中 ,能量产投比出现 2个高峰和 1个低谷 ,自 80年代高峰过后 ,大多数县市产投比下降 ,其中天祝县产投比最低 ,1994年仅为 0 .83。 7县市中酒泉市、民乐县、天祝县、武威市、张掖市农田单位面积投能分别超出其临界值 :5 .66× 10 3、4 .61× 10 3、8.73× 10 3、15 .91× 10 3和 36.84× 10 3MJ/ hm2。 相似文献
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Digestible and metabolizable energy in corn grains from different origins for growing pigs 下载免费PDF全文
下载免费PDF全文 An experiment was conducted to determine the digestible energy (DE) and metabolizable energy (ME) concentrations in nine sources of corn grains fed to growing pigs and to compare the energy values among their countries of origin. A total of nine sources of corn grains including five sources of yellow corn from the United States (USY), two sources of yellow corn from South Africa (SAY), and two sources of white corn from South Africa (SAW) were used. Nine barrows with an initial body weight of 37.1 ± 8.6 kg were allotted to a 9 × 9 Latin square design with nine diets and nine periods. The DE concentration in SAY (3347 kcal/kg) was greater (P < 0.001) than in USY (3269 kcal/kg), but was less (P < 0.001) than in SAW (3436 kcal/kg) on an as‐fed basis. Similarly, the ME concentration in SAY (3291 kcal/kg) was greater (P < 0.001) than in USY (3209 kcal/kg), but was less (P < 0.001) than in SAW (3386 kcal/kg). In conclusion, the DE and ME concentrations in nine sources of corn grains are different among their countries of origin. 相似文献
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Vivian Pedrinelli Mariana Yukari Hayasaki Porsani Daniel Magalhães Lima Fabio Alves Teixeira Caio Nogueira Duarte Thiago Henrique Annibale Vendramini Márcio Antonio Brunetto 《Journal of animal physiology and animal nutrition》2021,105(Z2):63-69
Maintenance energy requirement (MER) is the energy amount necessary for dogs to maintain their weight and body condition. Some factors can influence the MER, such as gender, age, neutering status and also diseases. The present retrospective study aimed to evaluate MER of adult dogs with several diseases and compare with the MER of healthy adult dogs, observing the influence of parameters such as body condition score (BCS), neutering status, gender, age, diagnosis and type of food on MER of these dogs. A total of 165 adult dogs with weight changes of ≤5% were included and divided in groups according to diagnosis. Mean MER for healthy dogs was 86.09 kcal/BW0.75, which differed from NRC and FEDIAF recommendations for inactive adult dogs (p = .047). Lowest MERs were of the endocrinopathies (78.52 ± 19.32 kcal/BW0.75), orthopaedic diseases (59.71 ± 19.30 kcal/BW0.75) and neurologic diseases (78.83 ± 32.66 kcal/BW0.75) groups. Gastrointestinal diseases (99.59 ± 20.36 kcal/BW0.75), orthopaedic diseases (59.71 ± 19.30 kcal/BW0.75) and neoplasia (95.61 ± 21.02 kcal/BW0.75) groups were the only groups that differed from the mean MER of healthy adult dogs. Regarding BCS, for each increasing point in a 9-point scale, there was a decrease of 9.8 kcal/BW0.75 on MER, independent of diagnosis (p < .0001; r2 = .55). There was no difference regarding breed size gender and age, but neutered dogs presented lower MER (p = .031). Based on data obtained from the present study, it can be concluded that it is necessary to consider BCS, age, neutering status and diagnosis when calculating MER, both in healthy dogs and chronically ill dogs. 相似文献
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A.-E. Liinamo P. Mäntysaari M. H. Lidauer E. A. Mäntysaari 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(2):63-72
AbstractOur aim was to estimate the genetic parameters of residual energy intake (REI) and energy conversion efficiency (ECE), and their relationships with milk, feed intake and body weight (BW) and condition in Nordic Red dairy cattle with data from 400 animals. These data were analysed with repeatability and random regression models. The highest heritabilities for energy efficiency traits were obtained in the beginning and the end of the 30 week lactation period (0.21–0.40). The results suggest that the energy efficiencies in early- and mid-lactation periods are partially different traits. The genetic correlations of REI were moderate to high and positive with the other studied traits, and high and positive for ECE with milk, but moderate to low and negative with dry matter intake, BW and body condition score. Further improvements are still needed in modelling the energy efficiency traits of cows during lactation. 相似文献
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S. Moehn C. L. Levesque R. O. Ball 《Journal of animal physiology and animal nutrition》2013,97(1):197-204
The effects of dietary protein and feeding levels on dietary metabolizable (ME) and net energy (NE) content were determined in 24 pigs, each offered two diets at 2.0 times the energetic maintenance requirement or for ad libitum intake between 55 and 95 kg body weight. Within feeding levels, pigs received, in random order, low‐protein (LP; 11.2% CP, 0.61% lysine) or high‐protein (HP; 20.2% CP, 0.61% lysine) diets of similar digestible energy content. Dietary NE was calculated from heat production based on 24‐h indirect calorimetry following a 7‐day N‐balance period. Feed intake was greater for LP than HP when fed for ad libitum intake (p = 0.001). Protein level did not affect daily gain (p > 0.1) but HP improved gain: feed (p = 0.003). Dietary ME and NE were not significantly affected by feeding level but were decreased by high protein intake (p < 0.07). Reducing dietary protein reduced urinary energy losses and increased energy retention but did not affect heat production. The effect of dietary protein restriction was already evident on the ME level and carried over to a similar degree to the NE level because the utilization of ME was not affected by protein level. Dietary ME and NE decreased by 0.012 MJ/kg (p = 0.014) and 0.018 MJ/kg (p = 0.062), respectively, for each gram per day N intake. The results suggest that although there was an effect of protein level on NE, the greatest effect occurred at the level of ME. However, the prediction of both ME and NE may be improved by adopting energy values for dietary protein that changes with dietary protein content. 相似文献