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1.
Iterative linear programming methods are proposed for optimum balanced animal diet in this paper. According to ＂wooden bucket theory＂ of the nutritional balance, each nutrient in the feeding standard has equal importance. It＇s unreasonable to use common goal programming to attach different weighted value to different nutritional parameters. This paper introduces an effective algorithm to deal with this kind of problem. When the permitting cost of livestock ration is given, we can design a ration formula with linear program-this is the first round. Then, according to the differences between the permitting cost and the formula cost gained in the first round, adjust the feeding standard and the feeding raw materials, and conduct the second round of linear programming for ration formula. If there is still a very big difference between the formula cost and the permitting cost, the third round will be taken, and so on. In this iteration course the formula cost gradually approaches the permitting cost. It is the key that the feeding standard and feeding raw materials are modified in each round. This method ensured the nutritive equilibrium with the formulation of least-cost ration. This is an especially important method when the primary goal of the optimization tool is to improve economic and nutritive efficiency. 相似文献
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To investigate the effects of different sources of carbohydrates on intake, digestibility, chewing, and performance, nine lactating Holstein dairy cows （day in milk= 100±21 d; body weight=645.7 ± 26.5 kg） were allotted to a 3 × 3 Latin square design at three 23-d periods. The three treatments included 34.91% （B）, 18.87% （BC）, and 18.86% （BB） barley that in treatment B was partially replaced with only corn or corn plus beet pulp in treatments BC and BB, respectively. The concentration of starch and neutral detergent soluble carbohydrate varied （22.2, 20.2, and 14.5; 13.6, 15.9, and 20.1% of DM in treatments B, BC, and BB, respectively）. Cows in treatment BB showed a higher DMI and improved digestibility of DM, NDF, and EE compared with treatments B or BC Ruminal pH was higher in cows fed on BB （6.83） compared with those that received B or BC treatments （6.62 and 6.73, respectively）. A lower proportion of propionate accompanied the higher pH in the BB group; however, a greater proportion of acetate and acetate： propionate ratio was observed compared with cows fed either on the B or BC diet. Moreover, cows fed on the BB diet showed the lowest ruminal passage rate and longest ruminal and total retention time. Eating time did not differ among treatments, rumination time was greater among cows fed on the BB diet compared with the others, whereas total chewing activity was greater than those fed on BC, but similar to those fed on B. The treatments showed no effect on milk yield. Partially replacing barley with corn or beet pulp resulted in an increase in milk fat and a lower protein concentration. Changing dietary NFC with that of a different degradability thus altered intake, chewing activity, ruminal environment, retention time or passage rate, and lactation performance. The results of this study showed that beet pulp with a higher NDF and a detergent-soluble carbohydrate or pectin established a more consistent ruminal mat than barley and corn, thus resulting in higher mean retention t 相似文献
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Treatment of wheat straw using tannase and white-rot fungus to improve feed utilization by ruminants 总被引：1，自引：0，他引：1
Background： Current research to enrich cattle feed has primarily focused on treatment using white rot fungi, while there are scarce reports using the enzyme tannase, which is discussed only in reviews or in the form of a hypothesis. In this context, the aim of the present study was to evaluate the effect of tannase on wheat straw （WS） and also the effect of lyophilized tannase at concentrations of 0.1%, 0.2%, and 0.3% （w/w） on WS followed by fermentation with Ganodermo sp. for 10 d and compared in relation to biochemical parameters, crude protein （CP） content, and nutritional value by calculating the C/N ratio in order to improve the nutritional value of cattle feed. Results： Penicillium charlesii, a tannase-producing microorganism, produced 61.4 IU/mL of tannase in 54 h when 2% （w/v） tannic acid （TA） was initially used as a substrate in medium containing （% w/v） sucrose （1.0）, NaNO3 （1.0）, and MgSO4 （0.08 pH, 5.0） in a 300-L fermentor （working volume 220 L）, and concomitantly fed with 1.0% （w/v） TA after 24 h. The yield of partially purified and lyophilized tannase was 5.8 IU/mg. The tannin-free myco-straw at 0.1% （w/w） tannase showed 37.8% （w/w） lignin degradation with only a 20.4% （w/w） decrease in cellulose content and the in vitro feed digestibility was 32.2%. An increase in CP content （up to 1.28-fold） along with a lower C/N ratio of 25.0%, as compared to myco-straw, was obtained. Conclusions： The use of tannin-free myco-straw has potential to improve the nutritional content of cattle feed. This biological treatment process was safe, eco-friendly, easy to perform, and was less expensive as compared to other treatment methods. 相似文献
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Comelina sotivo is an oil seed crop which can be grown on marginal lands. Camelina seed oil is rich in omega-3 fatty acids （〉35%） and y-tocopherol but is also high in erucic acid and glucosinolates. Camelina meal, is the by-product after the oil has been extracted. Camelina meal was fed to 28 d old weaned pigs at 3.7% and 7.4% unt age 56 d. The camelina meal supplements in the soy based diets, improved feed efficiency but also significantly increased the liver weights. Gene expression analyses of the livers, using intra-species microarrays, identified increased expression of phase 1 and phase 2 drug metabolism enzymes. The porcine versions of the enzymes were confirmed by real time PCR. Cytochrome 8b1 （CYPSB1）, aldehyde dehydrogenase 2 （Aldh2）, and thiosulfate transferase （TST） were all significantly stimulated. Collectively, these genes implicate the camelina glucosinolate metabolite, methyl-sulfinyldecyl isothiocyanate, as the main xeniobiotic, causing increased hepatic metabolism and increased liver weight. 相似文献
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Background： Helicobacter pylori, a gram-negative bacterial pathogen that expresses a strong urease activity, is associated with the development of gastroduodenal disease. Urease B subunit, one of the two structural subunits of urease, was expressed in E. coil BL21 （DE3） strain. The objective of this study was to evaluate the effects of He/icobacter py/ori urease B subunit on the immune responses in mice by subcutaneous immunization. Methods： The mice were immunized and boosted with Helicobacter pylori urease B subunit antigen subcutaneously three times with 2-wk intervals between the immunizations and boosters. The mice in the control group were immunized with PBS. The adjuvant group received PBS containing complete/incomplete freund＇s adjuvant identical to antigen group without Helicobocter pylori urease B subunit antigen. Four weeks after the final booster, all the mice were sacrificed. Blood was collected on d 0, 14, 28 and 56 before immunization, booster and sacrifice, respectively. Immediately after sacrifice, gastric liquid and spleen were collected for antibody and cytokine analyses. Results： Urease B subunit increased the concentrations of serum and gastric anti-urease B antigen specific IgG, and the levels of interteukin-4 and interferon-y in splenocytes of the mice （P 〈 0.05）. Conclusions： This study demonstrated that recombinant responses in mice by subcutaneous immunization, which against Helicobocter pylori. urease B subunit can induce systemic and local immune might be used as the effective component of vaccine 相似文献
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Background： Corn silage is the main dietary component used for ruminant breeding in China and is an important dietary source of fatty acids for these animals. However, little is known regarding effective means to protect the fatty acid （FA） contents in silages. In this study, we examined the changes in FA contents and compositions during corn ensiling and screened several antioxidants for their inhibition of lipid oxidation during corn ensiling. Methods： We conducted two different experiments. In Experiment 1, corn was ensiled in 30 polyethylene bottles （bottle volume： 1 L, silage density： 600 g/dm3） and three bottles were opened at 0.5 d, 1 d, 1.5 d, 2 d, 2.5 d, 3 d, 5 d, 7 d, 14 d, and 28 d after ensiling. In Experiment 2, corn was treated with various antioxidants： （1） No additives （CK）; （2） BHA （Butylated hydroxyanisole）; （3） TBHQ （Tertiary butyl hydroquinone）; （4） TPP （Tea polyphenols）; and （5） VE （Vitamin E）. These treatments were applied at 50 mg/kg and 100 mg/kg of fresh weight with each treatment replicated 3 times. Results： During ensiling in Experiment 1, saturated fatty acids （SFA; C16：0 and C18：0） and malondialdehyde （MDA） contents tended to increase, whereas unsaturated fatty acids （UFA; C18：1, C18：2 and C1 8：3） tended to decrease. However, these changes were only significant on the first 2 days of ensiling. In Experiment 2, all of the antioxidants tested affected the total FA contents and those of unsaturated fatty acids （C1 8：1, C18：2 and C18：3） and MDA. The effects of TBHQ and TPP were greater than those of the other antioxidants. Conclusions; The reduced total FA contents in corn silages were due to unsaturated fatty acids＇ oxidation during the early stages of ensiling. Adding an antioxidant could prevent fattv acids＇ oxidation in corn silages. 相似文献
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People have paid more and more attention to the environment contamination, especially the contamination of phosphorus excreted by livestock in resent years. This paper reviewed some measures to reduce the phosphorus contamination covering molecular biological technology, nutrition regulation, feed processing and feces treatment. 相似文献
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Rafael A Cabrera James L Usry Consuelo Arrellano Eduardo T Nogueira Marianne Kutschenko Adam J Moeser Jack Odle 《畜牧与生物技术杂志(英文版)》2013,(3):211-222
Background： Creep feeding is used to stimulate piglet post-weaning feed consumption.L-Glutamine（GLN） is an important source of fuel for intestinal epithelial cells.The objective of this study was to determine the impact of creep feeding and adding GLN or AminoGut（AG;containing glutamine ＋ glutamate） to pre-and post-weaning diets on pig performance and intestinal health.Litters（N = 120） were allotted to four treatments during 14–21 d of lactation： 1） No creep feed（NC,n = 45）;2） creep fed control diet（CFCD,n = 45）;3） creep fed 1% GLN（CFGLN,n = 15）;4） creep fed.88% AG（CFAG,n = 15）.After weaning,the NC and CFCD groups were sub-divided into three groups（n = 15 each）,receiving either a control nursery diet（NC-CD,CFCD-CD） or a diet supplemented with either GLN（NC-GLN,CFCD-GLN） or with AG（NC-AG,CFCD-AG）.Litters that were creep fed with diets containing GLN or AG also were supplemented with those amino acids in the nursery diets（CFGLN-GLN,CFAG-AG）.Glutamine was added at 1% in all three post-weaning diet phases and AG was added at.88% in phase 1 and 2 and at.66% in phase 3.Results： Feed conversion（feed/gain） showed means among treatment means close to significance（P = 0.056） and Tukey＇s test for pairwise mean comparisons showed that Pigs in the CFGLN-GLN group had the best feed conversion（feed/gain） in the first three-week period post-weaning,exceeding（P = 0.044） controls（CFCD-CD） by 34%.The NC-AG group had（P = 0.02） the greatest feed intake in the last three week of the study,exceeding controls（CFCD-CD） by 12%.CFGLN-GLN,CFCD-GLN and sow reared（SR） pigs had the greatest（P = 0.049） villi height exceeding the CFCD-AG group by 18%,20% and 19% respectively.The CFAG-AG group had the deepest（P = 0.001） crypts among all treatments.CFGLN-GLN,CFCD-GLN and SR groups had the greatest（P = 0.001） number of cells proliferating（PCNA） exceeding those in the NC-CD group by 43%,54% and 63% respectively.Sow reared pigs showed the greatest（P = 0.001） intestinal absorption capacity for xylose and mannitol.Conclusion： Supplementation of creep feed and nursery diets with GLN and/or AminoGut in the first three week improved feed conversion possibly due to improved intestinal health. 相似文献
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The availability of local feed resources in various seasons can contribute as essential sources of carbohydrate and protein which significantly impact rumen fermentation and the subsequent productivity of the ruminant.Recent developments,based on enriching protein in cassava chips,have yielded yeast fermented cassava chip protein（YEFECAP） providing up to 47.5% crude protein（CP）,which can be used to replace soybean meal.The use of fodder trees has been developed through the process of pelleting;Leucaena leucocephala leaf pellets（LLP）,mulberry leaf pellets（MUP） and mangosteen peel and/or garlic pellets,can be used as good sources of protein to supplement ruminant feeding.Apart from producing volatile fatty acids and microbial proteins,greenhouse gases such as methane are also produced in the rumen.Several methods have been used to reduce rumen methane.However,among many approaches,nutritional manipulation using feed formulation and feeding management,especially the use of plant extracts or plants containing secondary compounds（condensed tannins and saponins） and plant oils,has been reported.This approach could help todecrease rumen protozoa and methanogens and thus mitigate the production of methane.At present,more research concerning this burning issue-the role of livestock in global warming-warrants undertaking further research with regard to economic viability and practical feasibility. 相似文献
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Angela R Mays Michael L Looper Benjamin C Williamson Kenneth P Coffey Wayne K Coblentz Glen E Aiken Charles F Rosenkrans Jr 《畜牧与生物技术杂志(英文版)》2013,(3):165-169
Background： Integration of behavioral observations with traditional selection schemes may lead to enhanced animal well-being and more profitable forage-based cattle production systems.Brahman-influenced（BR;n = 64） and Gelbvieh × Angus（GA;n = 64） heifers consumed either toxic endophyte-infected tall fescue（E＋） or one of two nontoxic endophyte-infected tall fescue（NT） cultivars during two yr.Heifers were weighed at midpoint and termination of grazing.Grazing behavior（grazing,resting in the shade,lying,or standing without grazing） was recorded（n = 13 visual observations per yr in June and July） for each pasture.During yr 2,exit velocity（EV） and serum prolactin（PRL） were determined.Results： Grazing behavior was influenced（P 0.05） by an interaction between fescue cultivar and breed type.Gelbvieh × Angus heifers assigned to E＋ pastures had the lowest percentage of animals grazing and the largest percentage of animals resting in the shade.Brahman-influenced heifers had faster EV（P 0.001） than GA heifers（0.52 vs.0.74 ± 0.04 s/m,respectively）.Body weight（BW） was affected（P 0.01） by an interaction of tall fescue cultivar and d,and an interaction of tall fescue cultivar and breed type.Heifers grazing NT pastures were heavier（P 0.01） than heifers grazing E＋ pastures at midpoint and termination.Gelbvieh × Angus heifers grazing NT pastures were heavier（P 0.01） than GA and BR heifers grazing E＋ and BR heifers grazing NT pastures.An interaction of forage cultivar and breed type occurred on serum PRL（P 0.01）.Conclusion： Collectively fescue cultivar,EV,and concentrations of serum PRL were associated with grazing behavior.Heifers grazing NT pastures were observed to be grazing more than heifers assigned to E＋ pastures,regardless of breed type,which may have contributed to changes in BW and average daily gain（ADG） in heifers.Integration of behavioral observations along with traditional selection schemes may lead to enhanced animal well-being and more profitable forage-based cattle production systems. 相似文献
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The intestine and the gut-associated lymphoid tissue（GALT） are essential components of whole body immune defense,protecting the body from foreign antigens and pathogens,while allowing tolerance to commensal bacteria and dietary antigens.The requirement for protein to support the immune system is well established.Less is known regarding the immune modifying properties of individual amino acids,particularly on the GALT.Both oral and parenteral feeding studies have established convincing evidence that not only the total protein intake,but the availability of specific dietary amino acids（in particular glutamine,glutamate,and arginine,and perhaps methionine,cysteine and threonine） are essential to optimizing the immune functions of the intestine and the proximal resident immune cells.These amino acids each have unique properties that include,maintaining the integrity,growth and function of the intestine,as well as normalizing inflammatory cytokine secretion and improving T-lymphocyte numbers,specific T cell functions,and the secretion of IgA by lamina propria cells.Our understanding of this area has come from studies that have supplemented single amino acids to a mixed protein diet and measuring the effect on specific immune parameters.Future studies should be designed using amino acid mixtures that target a number of specific functions of GALT in order to optimize immune function in domestic animals and humans during critical periods of development and various disease states. 相似文献
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Improving efficiency of sow productivity： nutrition and health 总被引：2，自引：0，他引：2
This reviews research focused to understand the nutrient requirement and balance to meet the needs of fetal growth,mammary growth,and milk production.This summary will handle how feeding strategies can be adjusted according to the nutrient needs for a sow to enhance productivity and health.Most research data used in this summary are based on the studies conducted by the authors between 1996 and 2013.Nutrient requirements of sows are affected by stage of gestation and parity of sows.Dietary antioxidant concentrations need to be re-evaluated for its sufficiency in sow diets especially to prevent excessive oxidative stress during late gestation and lactation.When feeding sows,consideration of phase feeding of gestating sows and parity feeding of lactating sows could enhances production longevity and health of sows.Use of selected nutrients and additives seems to help productivity and health of sows. 相似文献
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Kangsen Mai 《饲料工业》2010,(2):5-6
This article presents a comprehensive review on the achievements obtained in the past a few decades and the prospects in aquaculture and aquafeed industry in China. The total production of aquaculture in China increased from 2.38 million tons in 1978 to 36 million tons in 2008, growing 15 times in 30 years. 相似文献
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Nutritional factors influence regulation of growth hormone （GH）, insulin-like growth factor-Ⅰ （IGF-Ⅰ） and insulin （INS） in fish. But so far there are no published studies describing how single indispensable amino acids and different carbohydrate to lipid ratios influence those systems. Therefore, the present study aimed to evaluate whether arginine （Arg） intake and carbohydrate to lipid ratios would affect expression of GH, IGF-Ⅰ and INS in largemouth bass. 相似文献
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Background： Post-production fractionation of wheat distillers grains with solubles（DDGS） increases their crude protein content and reduces their fiber content.This experiment was conducted to determine the effects of fractionation of wheat DDGS on apparent total tract digestibility（ATTD） and performance when fed to broiler chicks（0–21 d）.Methods： A total of 150,day-old,male broiler chicks（Ross-308 line;Lilydale Hatchery,Wynyard,Saskatchewan） weighing an average of 49.6 ± 0.8 g were assigned to one of five dietary treatments in a completely randomized design.The control diet was based on wheat and soybean meal and contained 20% regular wheat DDGS.The experimental diets contained 5,10,15 or 20% fractionated wheat DDGS added at the expense of regular wheat DDGS.Results： The ATTD of dry matter and gross energy were linearly increased（P 0.01） as the level of fractionated wheat DDGS in the diet increased.Nitrogen retention was unaffected by level of fractionated wheat DDGS（P 0.05）.Weight gain increased linearly（P = 0.05） as the level of fractionated wheat DDGS in the diet increased.Feed intake,feed conversion and mortality were unaffected by level of fractionated wheat DDGS in the diet（P 0.05）.Conclusions： Post-production fractionation of wheat DDGS improves their nutritional value by lowering their fiber content and increasing their content of crude protein and energy.These changes in chemical composition supported increased weight gain of broilers fed wheat DDGS. 相似文献
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Idrus Zulkifli 《畜牧与生物技术杂志(英文版)》2013,(3):180-186
Humans and animals are in regular and at times close contact in modern intensive farming systems.The quality of human-animal interactions can have a profound impact on the productivity and welfare of farm animals.Interactions by humans may be neutral,positive or negative in nature.Regular pleasant contact with humans may result in desirable alterations in the physiology,behaviour,health and productivity of farm animals.On the contrary,animals that were subjected to aversive human contact were highly fearful of humans and their growth and reproductive performance could be compromised.Farm animals are particularly sensitive to human stimulation that occurs early in life,while many systems of the animals are still developing.This may have long-lasting impact and could possibly modify their genetic potential.The question as to how human contact can have a positive impact on responses to stressors,and productivity is not well understood.Recent work in our laboratory suggested that pleasant human contact may alter ability to tolerate various stressors through enhanced heat shock protein（hsp） 70 expression.The induction of hsp is often associated with increased tolerance to environmental stressors and disease resistance in animals.The attitude and consequent behaviour of stockpeople affect the animals＇ fear of human which eventually influence animals＇ productivity and welfare.Other than attitude and behaviour,technical skills,knowledge,job motivation,commitment and job satisfaction are prerequisites for high job performance. 相似文献
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Four experimental diets were fed to turbet to examine the effect of fish bydrolyside and ultra filtered fish hydrolysafe on growth performate feed utilization and growth regulation using diets low in dietary fish meal inclusion. Diets A, B contained 3.7%,1.2% fish hydrolysate to replace fish meal respectively and the fish hydrolysate in two diets was ultra filtered to keep low molecular weight compounds. The diets A, 相似文献
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A six-week growth trial was conducted to compare the effects of different feeding strate- gies of dietary immunostimulants on the growth and immunity of white shrimp Litopenaeus vannamei （4.70 ±0.20g）. Shrimps were fed with diet containing glycyrrhizin continuously, containing β -glucan continuously, discontinuously （seven days with diet containing β -gluseven days with diet without -glucan; two days with diet containing β-glucan following five days with diet without -glucan）, 相似文献