Letteratura scientifica selezionata sul tema "Poultry Feeding and feeds"
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Articoli di riviste sul tema "Poultry Feeding and feeds"
1
Kolokolnikov, N., E. Amiranashvili, A. Yatsishin, E. Chaunina, I. Mezentsev e M. Mezentsev. "Super dose of phytase in compound feed for turkey poults". Kormlenie sel'skohozjajstvennyh zhivotnyh i kormoproizvodstvo (Feeding of agricultural animals and feed production), n. 9 (1 settembre 2020): 12–19. http://dx.doi.org/10.33920/sel-05-2009-02.
Testo completoAbstract (sommario):
In the practice of feeding poultry enzyme drugs are widely used that contribute to the effective transformation of feed components into poultry products. Reducing the cost of compound feed for poultry due to the introduction of enzyme drugs is of great interest, both from a scientific and practical point of view. More than 2/3 of phosphorus in plant feeds is represented in the form of phytate and in this form the element is only partially absorbed in the poultry body. Accordingly to cover the need for phosphorus in plant diets include inorganic phosphates, animal feed and the enzyme phytase (breaks down phytate). This makes phosphorus the third most expensive feed component after energy and protein. The purpose of the researches was to study the effectiveness of using super dose commercial phytase in feeding of turkey poults. The results of research on the use of high doses of phytase in the diet of turkey poults of cross Hybrid Converter have been presented. It has been found that the use of compound feeds containing the super dose of phytase in the rearing of broiler turkey poults does not have a negative influence on the zootechnical indicators of poultry rearing, meat productivity, and increases the economic indicators of meat production. The results on base the experiment, economic indicators have been calculated. It has been found that the cost of 1 ton of compound feed consumed in the experimental group was less than in the control group by 166,28 rubles or 0,7 %. The use of high doses of phytase in the diet of turkey poults of the experimental group allowed to reduce the cost of growth of 1 kg of live weight by 4,7 % and increase the profitability of meat production.
2
Çalışlar, Süleyman. "Kazlarda Selüloz ve Selüloz Fraksiyonlarının Sindirimi". Turkish Journal of Agriculture - Food Science and Technology 10, n. 1 (3 febbraio 2022): 42–48. http://dx.doi.org/10.24925/turjaf.v10i1.42-48.4808.
Testo completoAbstract (sommario):
Since the digestive system of poultry is quite short, the residence time of the feeds in the digestive system is also short. In addition, many poultry species have a low ability to digest and utilize cellulose, cellulose fractions (ADF and NDF) and non-starch polysaccharides. Therefore, it becomes necessary to use more expensive feeds with high nutrient content in poultry nutrition. This situation raises the prices of animal products such as white meat and eggs. In order to turn this disadvantage in poultry feeding into an advantage, alternative poultry with a stronger digestive system, better digestibility of cellulose-rich cheap feed sources and better utilization of roughage are needed. When evaluated in terms of its characteristics, it will be seen that one of the poultry that can better benefit from cheap feed sources is goose. The efficient use of cellulose-rich feeds, such as goose, reduces feed costs and provides a suitable opportunity to produce cheaper poultry products. Encouraging goose production can be an important source of income and livelihood, especially for the rural population. It is thought that goose breeding can be an important alternative for white meat and egg production because it benefits from cellulose-rich feeds better than other poultry. In this review, the microbial digestion properties of geese, their ability to benefit from cellulose fractions, especially cellulose, and non-starch feed elements were examined.
3
Mikula, P., J. Blahova, A. Honzlova, J. Kalinova, P. Macharackova, J. Rosmus, Z. Svobodova e M. Svoboda. "Occurrence of mycotoxins in complete poultry feeds in the Czech Republic – Multiannual survey (2013–2018)". Veterinární Medicína 65, No. 11 (26 novembre 2020): 487–94. http://dx.doi.org/10.17221/109/2020-vetmed.
Testo completoAbstract (sommario):
To assess the contamination and potential health risks for poultry, we investigated concentrations of selected mycotoxins in complete feeds sampled within the period of 2013–2018 in the Czech Republic. Broiler feeds, feeds for laying hens, chickens and/or other poultry species were investigated by ELISA methods or chromatography. Our results demonstrated that unlike other mycotoxins, (such as aflatoxins, ochratoxin A or zearalenone), deoxynivalenol (DON) may represent a potential threat. The prevalence of this mycotoxin in all the feed categories was very high, always reaching at least 81.29%. Moreover, in 14 of the 139 analysed broiler feed samples (i.e., in 10.81% of samples), DON was detected in concentrations exceeding the recent guidance value of 5 000 µg/kg established by EU legislation. Since previous studies demonstrated that the long-term feeding of such a highly contaminated diet could cause stress in the animals and could lead to their growth suppression, good agricultural practices and the further systematic monitoring of Czech poultry feeds are still highly needed.
4
Filmer, D. "Nutritional management of meat poultry". BSAP Occasional Publication 28 (2001): 133–46. http://dx.doi.org/10.1017/s1463981500041091.
Testo completoAbstract (sommario):
AbstractThe shortcomings of current feeding practices for meat poultry are illustrated and alternative systems discussed. These include automatic blending between high and low protein feeds at each poultry house, to deliver appropriate predetermined nutrient intakes daily. The benefits of using whole cereal as the low protein feed on gut pH, viscosity of gut contents, nutrient digestibility, litter quality and reductions in atmospheric pollution, and coccidial damage are discussed.Comparisons between current ad-lib feeding and various developmental stages of “Automated Controlled Feeding” are made. The alternative systems lead to proper function of birds' gizzards and crops and the benefits in terms of bird health, reduced mortality and variability, improved behaviour, and feed efficiency are illustrated.Currently available integrated management systems are described, and the principles behind a current MAFF LINK project discussed. This involves a real-time growth model that uses recorded liveweight, feed and nutrient intakes to date, to calculate the next day's nutrient intakes that will get birds back on target if they start to deviate from it.Future developments where the objective function could include minimising costs per kg liveweight or breast meat or maximising margin per bird placed or per square metre per year are discussed.
5
Fijalovych, L. M., Ya I. Kyryliv e G. А. Paskevych. "Features of providing broiler chickens with exchange energy and protein as important indicators of productivity and quality of the obtained products". Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 21, n. 91 (6 novembre 2019): 60–64. http://dx.doi.org/10.32718/nvlvet-a9110.
Testo completoAbstract (sommario):
The article deals with the possibility of using feed additives in the feeding of broiler chickens and the peculiarities of their effect on the poultry organism. Contemporary data on the biological role of nutrients and energy in the feeding of broiler chickens are presented. The characteristics of the main feeds for poultry and the ways of reducing their prime cost in the conditions of broiler farms are given. The basic principles of effective feeding of poultry with forages of different content of metabolic energy and crude protein are considered, taking into account their assimilation in the body. Provided compound feed recipes and practical tips. It is established that high growth rate of broiler chickens in the start and groove periods (5–39 days) is provided by high-protein compound feeds – 23% (1–2 weeks), 21% (3–5 weeks) and exchange energy of 298 kcal and 305 kcal, respectively. With further cultivation in the finish forage the protein content in the forage decreases and the level of metabolic energy increases (up to 309 kcal). However, for each cross applies its own technology of cultivation and different rates of nutrients in raw materials. It is clear that effective breeding of broiler chickens is not possible without the proper rationing and use of protein and feed energy. Of course, provided that the supply of biologically active substances also corresponds to the normalized amount. Thus, the quality of poultry products is directly dependent on the quality of feed and the efficiency of transformation of feed energy into products.
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Shpynova, Svetlana, Olga Yadrishchenskaya, Tatiana Selina e Elena Basova. "Beech flour in the diet of quails". Poultry and Chicken Products 24, n. 3 (2022): 39–42. http://dx.doi.org/10.30975/2073-4999-2022-24-3-39-42.
Testo completoAbstract (sommario):
To increase the meat productivity of quails, increase production volumes and reduce the cost of poultry production, it is necessary to include non-traditional additives in the poultry diet that contribute to the normalization of metabolic processes and improve the digestibility of feed nutrients. The article presents the results of a study on the use of beech flour in feeding meat quails. Feeding experimental compound feeds to quails increased the digestibility and use of nutrients, the profitability of meat production by 3 and 4.5%, and reduced costs per 1 kg of growth by 2.07 and 3.79%.
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Huque, KS, e NR Sarker. "Feeds and feeding of livestock in Bangladesh: performance, constraints and options forward". Bangladesh Journal of Animal Science 43, n. 1 (30 giugno 2014): 1–10. http://dx.doi.org/10.3329/bjas.v43i1.19378.
Testo completoAbstract (sommario):
Fibrous feeds mostly of crop residues, green grasses, and tree foliages and leaves support bulk diets of farm animals being raised mostly by smallholders. The roughage DM produced (51056 million kg) surpasses its demand (49200 million Kg) by 3.77%, but losses and otherwise uses result in production deficit of 44.5%. An average 56.2% deficit of roughage DM and 80.0% of concentrate DM results in a very poor plane of nutrition for farm animals. It supports an average diet containing 6.75 MJME/Kg DM and 1.63% DCP with the feed produced or 7.74 MJME/Kg DM and 2.32% DCP with the feed available, while a miserly calculation demands an average diet of at least 6.50 MJME/ Kg DM and 4.50% DCP. Brans and oilcakes sharing the bulk amount of concentrate feeds, except cereal maize being produced recently, often limit options for formulation of diets of higher metabolizability and quality protein including balancing of micronutrients essential for supporting nutritional planes for high yielding animals. Annual biomass demand and supply mismatch, harvest loss, bulk transfer problem, and otherwise uses of fibrous residues further limit feed supply to animals irrespective of their quality. Commercial poultry, on the other hand, is largely based on imported feeds except a part of corn. Different form of premixes, steroids, antibiotics and enzymes with or without knowing their quality and residual impacts on human health also used for poultry and bovine animals posing threats to food safety sometimes. The present poor plane of nutrition is not conducive to support an increased production of local or crossbred animals. Diversification and production of quality feeds and fodders, synchronization of feed production and availability to animals, strengthening feed milling capacity, conservation and improvement of new pasturage systems, mitigation of climate change impacts and domestic protection to feed safety and quality feed import are some of the options forward to increased supply of feeds and fodders help increased production and productivity of farm animals in the country.DOI: http://dx.doi.org/10.3329/bjas.v43i1.19378 Bang. J. Anim. Sci. 2014. 43 (1): 1-10
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Şengül, Ahmet Yusuf, Ömer Şengül e Aydın Daş. "The Possibilities of Using Fruit Waste in Nutrition of Poultry". Turkish Journal of Agriculture - Food Science and Technology 7, n. 5 (21 maggio 2019): 724. http://dx.doi.org/10.24925/turjaf.v7i5.724-730.2343.
Testo completoAbstract (sommario):
Particularly in the fruit juice industry, the remaining peels and pulp parts are not available for human consumption after the juices are used. It is possible to evaluate these wastes by adding them to poultry feeds. A number of studies have been conducted by researchers on the nutritional value of many fruit wastes and on the performance of poultry. Natural antioxidant content has been reported to have a positive effect on growth, microbial and immunological parameters when high fruit peels are used as feed additive in poultry feeding.
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Kolapo, Ademola Augustine, e Gbadeyanka Afees. "DETERMINATION OF NATURAL RADIONUCLIDE AND ASSESSMENTS OF HEALTH HAZARDS IN CHICKEN FEEDS AND MEAT CONSUMED IN LAGOS, NIGERIA". Malaysian Journal of Science 40, n. 2 (30 giugno 2021): 51–60. http://dx.doi.org/10.22452/mjs.vol40no2.5.
Testo completoAbstract (sommario):
Poultry farming is a highly profitable and not capital intensive agricultural project. It is becoming one of the highest investments in agriculture in Nigeria. The proliferation of self -produced feeds by the Farmers with the addition of some minerals to stimulate growth could elevate the levels of radionuclides in feeds. This, therefore, calls for the determination of the health effects from the consumption of these chicken meats and organs. 10 samples of broilers and 30 feed samples (10 each of Starter, Grower, and Finisher feeds used in feeding the chicken) were used; collected from five selected poultry- farms in Lagos State, Nigeria, and analyzed using spectrometry analysis with NaI (Tl). The results obtained showed that concentrations of 40K, 232Th, and 226Ra were 49.0±25.8, 24.9 ±12.2, and 32.9 ±16.2 Bqkg-1 respectively, in chicken meats. In the feeds, their values were below the UNSCEAR recommendation. The annual effective doses in chicken meats and organs were lower than the 70µSv/yr limit. The cancer risk was within the recommended limit, and the internal hazard indices were below unity. The mean values of the transfer coefficient (TC) were also below 1 for 40K, higher than unity for 226Ra in Finisher feeds, and 232Th in Starter feeds. The starter and finisher feeds were moderately contaminated. So, feeding chicken with these feeds may expose the consumers to the danger of over-exposure to 226Ra and 232Th.
10
Yegorov, Ivan, Yelena Andrianova, Nadezhda Zhivina e Alexey Balanovsky. "L-lisin sulphate in broiler feeding". Poultry and Chicken Products 25, n. 4 (2023): 15–19. http://dx.doi.org/10.30975/2073-4999-2023-25-4-15-19.
Testo completoAbstract (sommario):
The feed industry in the manufacture of balanced full-fledged compound feeds for poultry to ensure the regulatory content of lysine most often uses synthetic lysine monochlorohydrate, a significant disadvantage of which is the presence of chlorine. The problem of excessive chlorine content in the diet is solved using lysine sulfate. The article is devoted to the evaluation of the effectiveness of the use of liquid form of lysine sulfate in the feeding of broiler chickens, obtained using an improved technology that provides a higher yield of lysine.
Tesi sul tema "Poultry Feeding and feeds"
1
De, Silva Lekamwasam L. S. S. K. "Poultry feeds prepared from fermented prawn waste silage". Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/28068.
Testo completoAbstract (sommario):
The use of shrimp processing waste with other cheap raw materials such as cassava was studied as a potential low cost animal feed, specially in developing countries. The impact on the economies of the shrimp industry and possible effects on the environmental were taken into consideration in developing the project.
2
BACO, ABDUL-AZIZ ISHAK. "TALLOW FOR LAYING HENS (POULTRY, FAT, PERFORMANCE, AMINO ACIDS)". Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/188112.
Testo completoAbstract (sommario):
Effects of tallow supplementation on dietary nutrient and minimal amino acid utilization in the laying hen were studied in two experiments. In the first experiment diets contained six levels of animal tallow ranging from 0 to 10%. Percent egg production and egg mass were not significantly affected by tallow. Body weight was significantly increased by 2% tallow was maximum at 6%. Addition of up to 6% fat improved feed conversion without adversely affecting other production characteristics. Metabolizable energy (ME) intake increased from 305.1 to 322.4 kcal/hen/d over the range of 0 to 6% tallow with no further improvement at higher tallow levels. Maximum net energetic efficiency was obtained with 2 and 4% tallow. Ability to digest tallow declined significantly with hen age. Higher tallow ME values were obtained from calorimetry data than from digestibility measurements due to beneficial effects of tallow on digestibilities of fat and protein in the basal diet. No improvement in starch retention was observed with tallow supplementation. In the second experiment, diets containing four levels of protein (15.0, 13.6, 15.0 + methionine and 17.0%) without and with 3% tallow were fed to hens housed in an open cage house or an insulated, evaporatively cooled house. Egg production and egg mass were significantly higher in the insulated house. This study indicates that reducing total protein below the National Research Council (NRC, 1984) recommended level significantly reduced egg production by birds housed in an open house. Supplemental methionine to provide .60% TSAA was required for maximum egg production. Egg production was significantly improved with the low protein diet when 3% tallow was added; however, egg production rate supported by this combination was significantly below that obtained with the 17% protein diet either with or without added tallow. For birds housed in the insulated, evaporatively cooled house the diet based on the NRC amino acid recommendations appeared to be optimal for performance, even with a lower protein level. No additional benefits were obtained in egg production with 3% tallow in any of the diets under these housing conditions.
3
Ranwedzi, Ndivhuho Emmanuel. "An evaluation of family poultry production systems in the Northern region". Thesis, Port Elizabeth Technikon, 2002. http://hdl.handle.net/10948/93.
Testo completoAbstract (sommario):
Introduction : Family Poultry (FP) are birds of indigenous breeds living in almost symbiotic relationship with human communities. The chickens are usually free ranging, or have very limited restrains on their access to the village environment. African livestock population statistics for 1995 indicates poultry to be the most numerous species of farm animal (Anonymous, 1996a). More than 80% of poultry are kept in rural areas and contribute substantially to annual egg and meat production (Sonaiya, 1997). Throughout Africa poultry production stems from ancient traditional practices. FP is the most important type of poultry kept on the continent. In general, village producers keep small flocks of between 5 and 20 birds per household (Gueye, 1997a). Women and children play a key role in their management (Kitalyi, 1996). Because of its productivity, FP production has been neglected and is frequently considered by farmers as an insignificant occupation compared with other agricultural activities. Nevertheless, outside urban centers and especially in non-coastal areas, FP provides the population with a vital source of protein and income. In addition, they play an important role within the context of many social and/ or religious ceremonies. Although this type of poultry constitutes an important part of food security for rural households in South Africa, scientists have not explored this area of research for improving or recording this production system. Yet, FP survived for decades without being wiped out, in the interim, their keepers have gathered and stored a wealth of knowledge and experience, ensuring the survival of this genetic resource. The objective of this study was to collect the baseline data on FP production systems, determine their production constraints and achieve data for future use in the intervention strategies.
4
Lumbuenamo, Sita Ntula. "Effects of age and diet on exocrine pancreas function and fat digestibility in poultry". Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184810.
Testo completoAbstract (sommario):
Three experiments were conducted to study changes in exocrine pancreas function in relation to age, dietary fat and digestibility in poultry. In the first experiment, 120 White Leghorn and 120 Hubbard chicks were fed a basal diet with or without 5% animal fat. Total units of lipase, amylase, trypsin and chymotrypsin activities in pancreas increased linearly with age in Hubbards from 2 to 29 days, but plateaued after 16 days in Leghorns. Hubbards showed higher total pancreatic lipase, amylase, trypsin and chymotrypsin activities compared with Leghorns. Addition of 5% dietary fat significantly increased total lipase activity in pancreas, but decreased total amylase activity. Added fat had no well defined effect on total pancreatic trypsin and chymotrypsin activities. Fat digestibility in Leghorns fed the low fat diet increased significantly from 14 to 30 days of age, but not in Leghorns fed the high fat diet; while Hubbards fed both diets showed a significant decrease in fat digestibility. Fat digestibility was increased with added fat in both breeds. No direct correlation was found between nutrient digestibility and corresponding enzyme activity. In the second experiment, 80 young White Leghorn hens were fed a basal diet with or without 5% animal fat. Fat supplementation did not generally significantly affect lipase activities, but total lipase activity in pancreas decreased after 10.6 and increased after 12.7 mo in pancreata of birds fed both diets and fed the high fat diet, respectively. Fat digestibility was not affected by age, but was higher with fat supplementation. In the third experiment, 96 older White Leghorn hens were fed a basal diet with or without 5% animal fat. Total pancreatic lipase activity showed a U-shaped curve with the lowest value at 15.7 mo and increased after 15.7 mo following either natural or force molting. Fat supplementation did not significantly affect lipase activities. Amylase, trypsin and chymotrypsin activities decreased with age from 10.2 to 15.7 mo, but were increased with fat supplementation. Fat digestibility was not affected by age, but was significantly higher with fat supplementation.
5
Van, Niekerk S. J. (Sarel Johannes). "Actual and predicted performance of broiler chickens". Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/49817.
Testo completoAbstract (sommario):
Assignment (MPhil)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: The aim of this study was to evaluate the performance and profitability of different dietary specifications for broiler chickens slaughtered at 35 days of age. Two trials were performed to evaluate different production parameters. The results of these trials were compared to the predicted results of the EFG broiler model. No carcass data were available for the two trials mentioned above. Therefore, in order to evaluate the accuracy of the broiler model when predicting carcass characteristics, two published data sets (Leeson et al., 1996a) were used. Predicted and actual values were compared, evaluated and discussed. Two broiler trials were performed. In Trial One the amino acid density decreased throughout the range of three treatments from prestarter to finisher diets. In Trial Two the amino acid density decreased only in the four finisher diets. The main difference between predicted and actual results was the response to body weight. The model predicted a steady increase in feed intake to compensate for the lower dietary specifications while body weight did not change significantly. This increase in feed intake seems to be enough to maintain body weight. Trial birds also increased their feed intake as dietary amino acid density decreased, but this compensation seemed to be too low to maintain body weight compared to the control diet. The birds may find it easier to compensate when they have time to adapt to the specification. There is evidence in the literature that birds need seven days to adapt their feed intake to a lower feed specification (Leeson et al., 1996a). It can be speculated that the trial birds started to loose body weight due to a lower amino acid intake in this period. The model seems to adapt feed intake immediately after a change in diet specification. The simulation on literature data lead to the following conclusions: 1) Broilers posses the capacity to increase their feed intake with at least 65% should finisher diets with lower amino acid and energy concentrations be supplied. If only the energy concentration of finisher diets were decreased, the increase in feed intake will be around 30%. (see Table 16 and 23) 2) The accurate prediction of feed intake from the given dietary specification has a major influence on the accuracy of the prediction of broiler performance. 3) Amino acid density and DLys:ME ratio plays a significant role in the control and prediction of feed intake. The EFG broiler model is based on sound scientific principles. The model is comprehensive and can be used for a wide range of environmental and management conditions as well as dietary conditions. The nutritionist can use the model with confidence to assist in practical feed formulation. The actual strength of the model lies in the time and money being saved compared to practical trials.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie is om die prestasie en winsgewendheid van braaikuikens te bepaal wanneer voere met verskillende digthede tot op 35 dae gevoer word. Twee eksperimente is uitgevoer om produksieresultate te evalueer. Die resultate van hierdie eksperimente is met die voorspelde waardes uit die EFG simulasie-model vergelyk. Aangesien geen karkasdata vir bogenoemde eksperimente beskikbaar was nie, is twee gepubliseerde datastelle gebruik om hierdie deel van die model te evalueer (Leeson et al., 1996a). Twee braaikuiken eksperimente is uitgevoer. Eksperiment Een het uit drie behandelings bestaan waarvan die aminosuur-konsentrasie vanaf dag een tussen behandelings verskil het. In Eksperiment Twee het die aminosuur-konsentrasie net in die vier afrondingsdiëte verskil. Liggaamsmassa op 35 dae het die grooste verskil tussen voorspelde- en werklike waardes getoon. Beide voorspelde en werklike innames het in albei eksperimente verhoog soos wat aminosuur-konsentrasie afgeneem het. Voorspelde liggaamsmassa het egter konstant gebly terwyl werklike data 'n afname in liggaamsmassa getoon het. Dit bleik dat die voorspelde toename in innames voldoende was om massa te onderhou terwyl die voëls in werklikheid nie genoeg gekompenseer het nie. Leeson et al., 1996a het tot die gevolgtrekking gekom dat braaikuikens minstens sewe dae benodig om hul voeriname by 'n nuwe spesifikasie aan te pas. So 'n stadige aanpassing kan daartoe lei dat energie- en aminosuur-inname daal indien 'n dieet met laer spesifikasie gevoer. Dit sal daartoe lei dat die kuikens liggaamsmassa verloor. Uit die literatuur simulasies is die volgende afleidings gemaak: 1) Braaikuikens besit die vermoeë om voerinname in die afrondingstyd met minstens 65% te verhoog indien 'n afrondingvoer met laer amiosuur- asook energiekonsentrasie gevoer word. Indien net die energiekonsentrasie verlaag word, sal die inname met sowat 30% verhoog. 2) Die akkurate voorspelling van inname is krities vir die akkurate voorspelling van produksieparameters. 3) Aminosuur-digtheid en DLys:ME speel 'n belangrike rol in die beheer en voorspelling van voerinname by braaikuikens. Die EFG braaikuikenmodel is op suiwer wetenskaplike beginsels geskoei. Die model is omvattend en kan vir 'n wye reeks van omgewings- en bestuurstoestande asook dieet-spesifikasies gebruik word. Die voedingkundige kan die model met vertroue gebruik om met praktiese voerformulering by te staan. Die model kan die formuleerder baie tyd spaar aangesien praktiese eksperimente ingeperk kan word.
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Al-Hozab, Adel Abdullah. "THE EFFECT OF TALLOW ON TRUE METABOLIZABLE ENERGY OF SOME POULTRY FEEDSTUFFS (TME)". Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275342.
Testo completo
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Blake, John Paul. "Methodology for evaluating the digestibility and metabolizable energy of poultry feedstuffs". Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/49987.
Testo completoAbstract (sommario):
Determining the energy values of feed ingredients for poultry is of great concern, especially since production efficiency is associated with profit margins. Therefore, accurate, precise, and reproducible energy values for feed ingredients are of the utmost importance in formulating an economical diet.
An important aspect in determining the apparent metabolizable energy (AME) of a feed ingredient is the procedure employed in the drying of excreta samples. During sample preparation, substantial grinding losses were incurred amounting to 3.5 to 5.2% of the dried sample weight. Also moisture uptake during sample grinding accounted for a 1.9 to 3.9% increase in sample weight. To properly account for such losses, freshly collected excreta samples should be weighed, oven-dried at 40 C, reweighed, allowed to equilibrate with atmospheric moisture, weighed, ground, reweighed, and stored in air-tight containers for subsequent analyses.
From the oven-drying of feed and excreta samples at various temperatures, a linear decrease in sample weight occurred with increasing drying temperatures. When dried at 100 C or less, the energy content of feed and excreta samples remained unchanged, but increased significantly at higher temperatures. The nitrogen composition of feed and excreta samples exhibited a similar trend, but a significant loss of excreta nitrogen (2%) occurred at 100 C. The loss of excreta nitrogen at a temperature of 100 C is of relatively minor consequence in the determination of metabolizable dry matter, but is of major concern in nitrogen balance studies.
Extraction of feed and excreta samples with N,N-dimethylformamide and titration with Karl Fischer reagent indicated that significant amounts of water were retained by samples dried at 40, 60, and 80 C. However, at temperatures of 100 C or greater, little water was retained but sample decomposition occurred. A drying temperature of 90 C or the Karl Fischer method may yield a more accurate value for the dry matter of feed or excreta.
When seven roosters were subjected to a total collection method for five consecutive days, individual birds were better metabolizers of dry matter and energy than others. By either a voluntary intake method or by a total collection method, values for the nitrogen-corrected metabolizable energy of corn were similar. The total collection method proved to be more reliable since it provided the least amount of variation when ad libitum feed intake and total excreta output were measured over a period of several days.
In past experiments, adding fats to a test diet at the expense of cerelose in amounts no greater than 20% of the diet to determine the metabolizable energy of the fat has been associated with a high degree of variability. From the force-feeding of fats at levels to 100%, the variation associated with the metabolizable energy value of a fat was greatly reduced. The methodology presented here provided reliable estimates and detected differences between the metabolizable energy of two feed-grade fats in comparison to previous methods.Ph. D.
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8
Alabi, Olushola John. "Effect of lysine to energy ratio on the productivity and carcass characteristics of indigenous Venda chickens aged one to thirteen weeks and raised in closed confinement". Thesis, University of Limpopo, 2013. http://hdl.handle.net/10386/1397.
Testo completoAbstract (sommario):
Thesis (Ph. D. (Animal Production )) -- University of Limpopo, 2013Eight experiments were conducted to determine the effect of dietary lysine to energy ratio on the productivity and carcass characteristics of indigenous Venda chickens aged one to thirteen weeks and raised in closed confinement. The eight experiments were based on four different energy levels of 11, 12, 13 and 14 MJ of ME/kg DM. Each dietary energy level had four different levels of dietary lysine (8, 9, 11 and 14 g lysine/kg DM). Thus, different dietary lysine to energy ratios were calculated. Experiments 1 to 4 determined the effect of dietary lysine to energy ratio on productivity of unsexed Venda chickens aged one to seven weeks. Each experiment commenced with 160 unsexed day-old indigenous Venda chicks with an initial live weight of 30 ± 3 g per bird and was carried out for seven weeks. In each experiment, the chicks were randomly assigned to four treatments with four replications, each having 10 chicks. A complete randomized design was used for each experiment. All data were analysed by one-way analysis of variance. Where there were significant differences, the Duncan test for multiple comparisons was used to test the significance of differences between treatment means. A quadratic regression model was used to determine the ratios for optimum productivity in each experiment while a linear model was used to determine the relationships between dietary lysine to energy ratio and optimal responses in the variables measured. Results indicated that dietary lysine to energy ratio for optimal responses depended on the variable of interest. In Experiment 1, feed intake, growth rate, live weight, ME intake and nitrogen retention were optimized at different dietary lysine to energy ratios of 0.722, 0.719, 0.719, 0.670 and 0.712, respectively. There was a positive and strong relationship (r2 = 0.950) between dietary lysine to energy ratio and feed conversion ratio (FCR). Results from Experiment 2 indicated that feed intake, growth rate, FCR, live weight, ME intake and nitrogen retention were optimized at dietary lysine to energy ratios of 0.719, 0.742, 0.788, 0.742, 0.734 and 0.789, respectively. In Experiment 3, dietary lysine to energy ratio did not have any effect (P>0.05) on all the parameters measured. However, quadratic analysis indicated that dietary lysine to energy ratios of 0.817, 0.883, 0.920, 0.898, 0.895 and 0.955 optimized feed intake, growth rate, FCR, live weight, ME intake and nitrogen retention of the chickens, respectively. Experiment 4 results showed that feed intake, growth rate, FCR, live weight ME intake and nitrogen retention were v optimized at different dietary lysine to energy ratios of 0.906, 0.964, 1.023, 0.966, 0.963 and 0.951, respectively. Experiments 5 to 8 determined the effect of dietary lysine to energy ratio on productivity, carcass characteristics, sensory attributes and haematological values of female indigenous Venda chickens aged eight to thirteen weeks. The layouts, treatments, design and execution were similar to those described for Experiments 1, 2, 3 and 4, respectively, except that Experiments 5 to 8 were for female indigenous Venda chickens aged eight to 13 weeks. These chickens were different from those used in Experiments 1 to 4. They were raised on a grower mash (16 % crude protein, 11 MJ of ME/kg DM and 180 g of lysine) prior to commencement of the study. Each experiment commenced with 120 eight weeks old female Venda chickens with an initial live weight of 412 ± 3 g per chicken. In each experiment, the chickens were randomly assigned to four treatments with five replicates, each having six chickens. Results obtained from Experiment 5 showed that feed intake, growth rate, FCR, live weight, ME intake, carcass weight, dressing percentage, breast meat, drumstick, wing weight, breast meat drip loss, juiciness, flavour, haemoglobin and pack cell volume were optimized at different dietary lysine to energy ratios of 0.672, 0.646, 0639, 0.649, 0.655, 0.656, 0.664, 0.669, 0.665, 0.663, 0.631, 0.708, 0.623, 0.556 and 0.609, respectively. In Experiment 6, the diets were formulated to have higher lysine to energy ratios than those in Experiment 5 by using a dietary lysine level of 9 g lysine/kg DM. Results from this experiment showed that feed intake, FCR, nitrogen retention, carcass weight, dressing percentage, breast meat, gizzard weights and breast meat pH at 2, 12 and 24 hours after slaughter were optimized at dietary lysine to energy ratios of 0.798, 0.613, 0.777, 0.742, 0.753, 0.729, 0.758, 0.752, 0.802 and 0.797, respectively. Red blood cell and haemoglobin values in this experiment were optimized at dietary lysine to energy ratios of 0.480 and 0.624, respectively. In Experiment 7, dietary lysine to energy ratios of 0.79, 0.85, 0.92 and 1.00 g lysine/ MJ of ME were used. Dietary treatments in this experiment had no effect (P>0.05) on all the production parameters measured except feed and apparent metabolisable energy intakes. Quadratic analysis of the results indicated that dietary lysine to energy ratios of 0.964, 0.912, 0.900, 0.890, 0.910, 1.090, 0.934 and 0.895 optimized feed intake, apparent metabolisable energy, carcass, breast meat, drumstick weights and vi breast meat drip loss, juiciness and flavour, respectively. A positive and very strong relationship (r2 =0.998) was observed between dietary lysine to energy ratio and pack cell volume. Experiment 8 diets were formulated to have higher dietary lysine to energy ratios than the other experiments. Results of this experiment indicated that all the production parameters were influenced (P<0.05) by dietary lysine to energy ratio except mortality. Feed intake, growth rate, feed conversion ratio, live weight, apparent metabolisable energy and nitrogen retention were optimized at dietary lysine to energy ratios of 0.996, 0.980, 0.991, 1.010, 0.957 and 0.993, respectively. Dietary lysine to energy ratios of 0.992, 0.974, 0.991, 0.992, 1.023, 0.981, 0.979 and 0.815 optimized carcass weight, dressing percentage, breast meat, drumstick, liver weights and breast meat tenderness, juiciness and flavour, respectively. There were variations in the optimal lysine to energy ratios for different parameters investigated. In a diet containing 8 g of lysine per kg DM, 11.13 MJ of ME/kg DM and 150 g of CP/kg DM, dietary lysine to energy ratios of 0.719 and 0.649 are recommended for optimal live weight of Venda chickens aged one to seven and eight to 13 weeks, respectively. In a diet containing 9 g of lysine per kg DM, 12.13 MJ of ME/kg DM and 180 g of CP/kg DM, dietary lysine to energy ratios of 0.742 and 0.712 are recommended for optimal live weight of Venda chickens aged one to seven and eight to 13 weeks, respectively. In a diet containing 11 g of lysine per kg DM, 12.51 MJ of ME/kg DM and 220 g of CP/kg DM, dietary lysine to energy ratios of 0.878 and 0.894 are recommended for optimal live weight of Venda chickens aged one to seven and eight to 13 weeks respectively. In a diet containing 12 g of lysine per kg DM, 12.05 MJ of ME/kg DM and 240 g of CP/kg DM, dietary lysine to energy ratios of 0.996 and 1.010 are recommended for optimal live weight of Venda chickens aged one to seven and eight to 13 weeks, respectively. The results obtained in this study showed that different production parameters of Venda chickens were optimized at different lysine to energy ratios. This implies that the nutritional requirements of these chickens are dynamic and thus, dietary lysine to energy for optimal production depends on the production parameter of interest. This has implications on ration formulation for indigenous chickens.
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Iji, Paul Ade. "Natural development and dietary regulation of body and intestinal growth in broiler chickens". Title page, contents and summary only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phi25.pdf.
Testo completoAbstract (sommario):
Corrigenda inserted behind title page. Bibliography: leaves 275-306. The pattern of body growth and intestinal development of an Australian strain of broiler chicken, the Steggles x Ross (F1) in response to different diets was studied. Five experiments were designed to examine the pattern of growth and mechanisms involved. In four other experiments, the mechanisms underlying the gross response of the broiler chicks to dietary ingredients, anti-nutritive factors and growth enhancers were examined. Results indicated that a rapid development of the small intestine preceded significant overall body growth. Body growth would, however, depend more on the various physiological events such as those related to mucosal growth and renewal, digestive enzyme function, and nutrient transport. Some of the differences observed in productivity of broiler chickens on different diets were traced to events at the intestinal level.
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Emmerson, Derek Alan. "The effect of protein and energy self-selection on the reproductive performance of turkey hens". Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53166.
Testo completoAbstract (sommario):
Two experiments were conducted to determine the effect of dietary self-selection of protein and energy on the reproductive performance of Large White turkey hens. The first study examined the effect of self-selection on reproductive performance during a production cycle that started in July and ended in December. Hens were maintained on one of two dietary regimes for a 20-week production cycle. Control birds were fed a conventional diet (18% crude protein, 2700 kcal/kg) which contained nutrients at levels recommended by the National Research Council (NRC, 1984). The remaining hens were allowed to select their diet from two feed sources: one relatively high in protein and low in energy (35% crude protein, 1850 kcal/kg) and the other relatively low in protein and high in energy (8% crude protein, 3220 kcal/kg). Hens fed the split diet produced an equal number of eggs as control hens but consumed significantly less feed (p≤.05). The diet that was selected contained approximately 40% less protein than the control diet (p≤.001) which resulted in significantly increased efficiency of protein utilization (eggs/kg protein) for hens fed the split-diet (p≤.001). In addition, the incidence of broodiness was significantly reduced in the split-diet treatment (p≤.10). Egg weight, fertility, hatchability and hatch of fertile eggs were not significantly effected by the dietary regimes. There was significantly greater body weight loss in hens fed the split-diet (p≤.05). Increasing trends in feed, energy, and protein consumptions were noted over the course of production. For this reason a second experiment was conducted to determine if these trends were the result of seasonal affects, due to changing ambient temperatures, or the result of changes in nutrient requirements of the turkey hen occurring with different stages of production.
The second experiment was similar to Experiment 1 except that the production period started in March and ended in July. As in the first experiment, egg production was equal for hens in the two treatment groups. Feed intake and energy intake were not significantly different for hens fed the split and complete diets. However, as in the previous experiment, protein intake was significantly reduced in the split-diet treatment (p≤.001). The incidence of broodiness was again attenuated among split-fed birds (p≤.10). Average daily feed and energy intake appeared to decrease over the course of production which was presumed to be related to increasing ambient temperatures. As in the previous experiment, protein intake increased over the course of production despite increasing environmental temperatures. Therefore, the increased protein selection noted in these two experiments does not seem to be related to hot weather and may indicate an increased protein requirement in the later stages of egg production.
Based on the finding that the incidence of broodiness was reduced among hens fed the split-diet, blood sera from hens in both experiments were analyzed for luteinizing hormone (LH) and prolactin (PRL). Although the incidence of broodiness was significantly reduced among birds fed the split-diet, there was no significant difference in serum LH and PRL concentrations. Therefore, the reduction in the incidence of broodiness that was noted in these experiments was not correlated with changes in the blood concentration of these hormones.Master of Science
Libri sul tema "Poultry Feeding and feeds"
1
Robertson, George. Poultry feeds and feeding. Ottawa: J. de L. Taché, 1997.
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2
National Research Council (U.S.). Subcommittee on Poultry Nutrition. Nutrient requirements of poultry. 9a ed. Washington, D.C: National Academy Press, 1994.
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3
Larbier, Michel. Nutrition and feeding of poultry. Loughborough: Nottingham University Press, 1994.
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4
B, Leclercq, e Wiseman J, a cura di. Nutrition and feeding of poultry. Loughborough, Leicestershire: Nottingham University Press, 1994.
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Leeson, Steven. Commercial poultry nutrition. Guelph, Ont: University Books, 1991.
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M, McNab J., Boorman K. N e Poultry Science Symposium (26th : 1999 : Edinburgh, Scotland), a cura di. Poultry feedstuffs: Supply, composition, and nutritive value. Wallington, Oxon: CABI Pub., 2002.
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A, Cole D. J., e Haresign William, a cura di. Recent developments in poultry nutrition. London: Butterworths, 1989.
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Jean-Claude, Blum, Wiseman Julian e Institut national de la recherche agronomique. Département de l'élevage des monogastriques., a cura di. Feeding of non-ruminant livestock. London: Butterworth, 1987.
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Damerow, Gail. A guide to raising chickens: Care, feeding, facilities. Pownal, Vt: Storey Communications, 1995.
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Development of Malawian Traders Trust., a cura di. Report on poultry feed availability and its potential for increased production in Malawi. Blantyre [Malawi]: DEMATT, 1990.
Cerca il testo completoCapitoli di libri sul tema "Poultry Feeding and feeds"
1
Mpairwe, Denis, e David Mutetikka. "Improved feeding for dairy cattle and poultry in smallholder crop-livestock systems." In Sustainable agricultural intensification: a handbook for practitioners in East and Southern Africa, 106–18. Wallingford: CABI, 2022. http://dx.doi.org/10.1079/9781800621602.0008.
Testo completoAbstract (sommario):
Abstract This chapter describes how cropping systems can be used to supplement feeds to increase dairy and poultry yields. It completes the concept of on-farm integration of crop, livestock and natural resources technologies necessary for sustainable intensification on smallholder farms. The different processes that utilize different feed sources to produce better-quality feed rations for dairy cows and poultry are also discussed.
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Hawkey, Kerensa, John Brameld, Tim Parr, Andrew Salter e Heidi Hall. "Suitability of insects for animal feeding." In Insects as animal feed: novel ingredients for use in pet, aquaculture and livestock diets, 26–38. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789245929.0004.
Testo completoAbstract (sommario):
Abstract This chapter explores the nutritional composition of insects and the potential benefits and drawbacks for their inclusion into pet, poultry, pig, ruminant and aquatic animal feeds. Six species are most commonly described for use in animal feed, namely black soldier fly (BSF; Hermetia illucens) larvae and prepupae, yellow mealworm (YM; Tenebrio molitor) larvae, superworm (SW; Zophobas morio) larvae, lesser mealworm (LM; Alphitobius diaperinus) larvae, house fly (HF; Musca domestica) larvae and house crickets (HC; Acheta domesticus). The nutritional composition, variability observed due to manipulation of feed source, age, developmental stage and suitability for inclusion into animal feed are compared.
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Abioja, M. O., e J. A. Abiona. "Impacts of Climate Change to Poultry Production in Africa: Adaptation Options for Broiler Chickens". In African Handbook of Climate Change Adaptation, 275–96. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-45106-6_111.
Testo completoAbstract (sommario):
AbstractGlobal climate change poses a great threat to poultry production. Greenhouse gases (GHGs) are released through both natural and anthropogenic sources into the atmosphere. Though poultry production contributes little to the release of GHGs, the subsector has been shown to be greatly affected by climate change and global warming. Poultry production as a major subsector of agriculture has provided the teeming population with a supply of needed animal protein in terms of meat and egg production all over the world. It is yet a major global employer of labor. Though it occupies a vantage position in meeting human needs, it is being threatened by climate change, especially in Africa where necessary structure to tackle the menace is nonexistent. Broiler chickens that are reared mainly for chicken meat cannot tolerate the high ambient temperature that prevails mostly in the tropical environment. Chickens are homeotherms that homeostatically regulate core body temperature within a narrow range. Elevated ambient temperature above thermal comfort zone, such as envisaged in climate change scenarios, will trigger series of neuroendocrine modulations that are detrimental to the welfare and productivity in broiler chickens. Such birds are said to be undergoing heat stress (HS). Negative effects of HS include reduced feed consumption, growth rate, feed digestion and efficiency, immunity, welfare, and survivability. Various adaptive measures that could be harnessed by broiler farmers, ranging from housing, feeding, watering, stocking, breeding for thermo-tolerant strains, thermal conditioning, use of phytochemicals, and much more, are reviewed upon in this chapter.
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Lukefahr, Steven. "Feeds and feeding." In Rabbit production, 107–24. 10a ed. Wallingford: CABI, 2022. http://dx.doi.org/10.1079/9781789249811.0008.
Testo completoAbstract (sommario):
Abstract This chapter discusses the nutrient requirements; feed formulation; feed composition of clovers, grasses, lucerne, concentrates, grains, feed supplements and feed additives; feed processing and feeding of rabbits.
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Tucker, Craig S., e Edwin H. Robinson. "Feeds and Feeding Practices". In Channel Catfish Farming Handbook, 291–315. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1376-3_11.
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Hertrampf, Joachim W., e Felicitas Piedad-Pascual. "Poultry By-Product Meal". In Handbook on Ingredients for Aquaculture Feeds, 330–37. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4018-8_35.
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Dryden, Gordon McL. "Digestion of feeds." In Fundamentals of applied animal nutrition, 19–34. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781786394453.0003.
Testo completoAbstract (sommario):
Abstract In this chapter the feeding behaviour and digestive physiology, digestive tract function-intrinsic and microbial digestion; functions and anatomy of the digestive tract in animals are discussed.
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Pomar, C., J. van Milgen e A. Remus. "18: Precision livestock feeding, principle and practice". In Poultry and pig nutrition, 397–418. The Netherlands: Wageningen Academic Publishers, 2019. http://dx.doi.org/10.3920/978-90-8686-884-1_18.
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Bedford, Michael R. "Xylanases, β-glucanases and cellulases: their relevance in poultry nutrition." In Enzymes in farm animal nutrition, 52–69. 3a ed. Wallingford: CABI, 2022. http://dx.doi.org/10.1079/9781789241563.0004.
Testo completoAbstract (sommario):
Abstract This chapter discusses the history of enzyme use in poultry feeds, non-starch polysaccharide-degrading enzymes (NSPases), mode of action of NSPases, nutrient encapsulation, viscosity, prebiotic effects of oligosaccharides, fibre digestion and future enzyme development.
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Garland, Patrick. "Feeding poultry and potential problems associated with diet." In Poultry Health: A Guide for Professionals, 79–85. UK: CABI, 2021. http://dx.doi.org/10.1079/9781789245042.0012.
Testo completoAtti di convegni sul tema "Poultry Feeding and feeds"
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Сорокин, Александр, Alexander Sorokin, Валентина Руцкая e Valentina Ruckaya. "LUPIN AS THE BASE FOR PROTEIN COMPONENT OF FEED MIX FOR POULTRY". In Multifunctional adaptive feed production. ru: Federal Williams Research Center of Forage Production and Agroecology, 2019. http://dx.doi.org/10.33814/mak-2019-21-69-110-115.
Testo completoAbstract (sommario):
The article presents the data of domestic and foreign researchers for feeding of poultry used lupin and its processed products. It’s advisable to use energy-and-protein concentrates made of legumes and cereal grain mixtures to prepare complete feeds. Lupin is one of the main sources of plant protein with unique amino acid composition. In opinion of the majority of researchers lupin containing feeds made according to technic guidance support productivity increasing of poultry growing and improve the quality of the products.
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Zverkova, Zinaida. "Practical application of surepitsa cake in the diets of poultry". In Multifunctional adaptive feed production 27 (75). ru: Federal Williams Research Center of Forage Production and Agroecology, 2022. http://dx.doi.org/10.33814/mak-2022-27-75-158-162.
Testo completoAbstract (sommario):
Studies have been conducted on the use of surepny oilcake obtained from different varieties of Brassica rapa L., in the feeding of broiler chickens. The safe norms of its inclusion in the composition of balanced compound feeds have been determined. The enrichment of experimental compound feed with enzyme preparations increases the economic performance of broiler chickens. The oilcake surepny obtained from the seeds of the Brassica rapa L, selection of the All-Russion Williams Fodder Research Institute confirms the effectiveness of cultivation and the negative effect on broiler chickens.
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Hotea, Ionela, Catalin Sirbu, Anamaria Plotuna, Emil Tirziu e Isidora Radulov. "ASSESSMENT OF CHEMICAL AND NUTRITIONAL QUALITY OF RAPESEED MEAL INTENDED FOR MONOGASTRIC LIVESTOCK FEEDING". In 23rd SGEM International Multidisciplinary Scientific GeoConference 2023. STEF92 Technology, 2023. http://dx.doi.org/10.5593/sgem2023v/6.2/s25.05.
Testo completoAbstract (sommario):
Rapeseed meal is a valuable source of protein for animals feeding. It can be used as an alternative to soybean meal in the mixtures of combined feeds intended for farm animals. Thus, the purpose of this study was to evaluate the chemical and nutritional composition of the rapeseed meal intended for use in the feeding of monogastric livestock. 70 samples of rapeseed meal arrived at the Laboratory of Chemical Analyses for Animal Nutrition, were analysed. The following values were obtained for the main nutritional compounds: crude protein (CP) � 37.95%, with variations between 35.26 and 41.67%; ether extract (EE) � 1.84%, with values between 1.55 � 2.06%; crude fiber (CF) � 11.93%, with variations between 9.85 � 14.93%; and nitrogen-free extracts (NfE) � 41.07%, varying significantly between 35.75 � 45.82%. In order to evaluate the nutritional value of rapeseed meal, the digestible forms of nutrients and the value of metabolizable energy (ME) for pigs and poultry were calculated, using predictive formulas. The average ME value for pigs was 1278.57 kcal/kg, varying between 1145.63 - 1398.27 kcal/kg, and for poultry the ME value was 935.06 kcal/kg, being between 837.90 - 1022.55 kcal/kg. These data underline the importance of the chemical and nutritional evaluation of feed ingredients before they are included in the diets of farm animals in order to have the certainty of correctly calculated rations and to ensure the amounts of nutrients in accordance with their feeding norms, in order to maximize animal production.
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Cerina, Sallija, e Liga Proskina. "Pea seeds and alfalfa hay pellets: to increase the economic return of poultry farms". In 23rd International Scientific Conference. “Economic Science for Rural Development 2022”. Latvia University of Life Sciences and Technologies. Faculty of Economics and Social Development, 2022. http://dx.doi.org/10.22616/esrd.2022.56.008.
Testo completoAbstract (sommario):
The output of poultry products by poultry enterprises in the world was mainly determined by feeding techniques and poultry productivity. The productivity of poultry is characterised by the rate of egg-laying or the number of eggs produced per hen a year and affected by the availability and diversity of feed materials (especially protein). In recent years, researchers have focused on legumes of various species as promising sources of protein for livestock production, such as beans, peas, lupine, alfalfa etc.; therefore, in Latvia more attention is paid to the production of protein crops or legumes. The aim of the research was to identify the impact of domestically sourced legume seeds included in diets for laying hens on the economic performance of egg production. Two kinds of protein crops were examined by the research: peas `Bruno` and dried alfalfa pellets. Feeding laying hens with peas or dried alfalfa pellets made it possible to produce eggs with a heavier weight (55.28-67.07%), which in turn makes it possible to increase revenues (10.3-12.9%) from the sales of eggs with the same feed consumption.
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Zverkova, Zinaida, e Bella Osipyan. "FEATURES OF THE USE OF BRASSICA RAPA SEEDS IN THE FEEDING OF BROILER-CHICKENS". In Multifunctional adaptive fodder production. ru: Federal Williams Research Center of Forage Production and Agroecology, 2022. http://dx.doi.org/10.33814/mak-2022-28-76-191-197.
Testo completoAbstract (sommario):
In the Federal Scientific Center "VIK im. V. R. Williams” conducted research on the evaluation of new varieties of spring and winter colza Zarya and Nadezhda when growing broiler chickens of the Cobb 500 cross. The control group received compound feed without rapeseed seeds. The first and second experimental groups included 7.5% by weight of mixed fodder native rapeseed seeds of Zarya and Nadezhda varieties, which were used to replace part of soybean meal and sunflower oil. The content of nutrients in mixed feed complied with the regulatory requirements. The oil was balanced in composition: a large amount of monounsaturated, low-saturated fatty acids, a moderate amount of polyunsaturated fatty acids. It has been established that compound feeds with rapeseed seeds do not negatively affect the live weight gain of experimental broiler chickens. On the 39th day, the live weight of chickens in the control, in the first and second experimental groups was 2.250, 2.245 and 2.256 g, respectively. The significance of the difference in this indicator with the control group has not been established (P > 0.05). In the study of blood serum in chickens of the first experimental group, an increased level of bilirubin and the enzyme glutamyltransferase was revealed, which indicates stagnation of bile in the bile ducts (P > 0.01). The efficiency of growing poultry using rapeseed seeds was higher than in the control, which is associated with a decrease in feed costs for obtaining meat products and a lower cost of experimental feed.
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Doković, Vladimir, e Snežana Bogosavljević-Bošković. "ENZIMI U ISHRANI BROJLERA". In XXVII savetovanje o biotehnologiji. University of Kragujevac, Faculty of Agronomy, 2022. http://dx.doi.org/10.46793/sbt27.229d.
Testo completoAbstract (sommario):
The paper presents the most important aspects of the action of exogenous enzymes (amylase, xylanase, glucanase, cellulase, hemicellulase, pectinase, phytase and protease) added to broiler feed. The addition of broiler feed enzymes has nutritional, health, economic and environmental justification. The use of complexes of exogenous enzymes (enzyme cocktails) as additives to complete mixtures for feeding broiler chickens in different phases of fattening, significantly increases the availability of reserve polysaccharides, fats, proteins and some minerals, better energy efficiency from food, better health of chickens, better quality carcasses and chicken meat, reducing the cost of feeding fattening chickens (and thus the total cost of production), as well as reducing environmental pollution and is one of the easiest feasible alternatives to improve the profitability of production in poultry.
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Ünlü, Elif Işılay, e Ahmet Çınar. "Lesion Detection on Skin Images Using Improved U-Net". In International Students Science Congress. Izmir International Guest Student Association, 2021. http://dx.doi.org/10.52460/issc.2021.022.
Testo completoAbstract (sommario):
The fate of transgenic DNA (tDNA) and protein of feeds from Genetically Modified organisms (GMOs) in animals has been an important topic since their commercialization in 1996. Several studies have investigated about risks of horizontal gene transfer (HGT) of tDNA and proteins to bacteria or animal cells/tissues, however, the reported data is at times controversial. Earlier reports showed that tDNA fragments or protein derived from GM plants have not been detected in tissues, fluids, or edible products of farm animals. Other researchers have come out to demonstrate that there is the possibility of small fragments leaking out into the animal tissues, fluids and organs. This motivated us to update our knowledge about these concerns. Therefore, this review aimed at assessing the likely transfer and accumulation of tDNA/ proteins from transgenic feeds to animal (ruminants and non-ruminants) samples through evaluating the available experimental scientific published studies. This study has found out that the tDNA or protein is not completely degraded during feed processing and digestion in the Gastro-Intestinal Tract (GIT). In large ruminants (Cattle), tDNA fragments/protein have been detected in the GIT digesta, ruminal fluid and feces. In small ruminants (Goats), traces of tDNA/proteins have been detected in the GIT digesta, blood, milk, liver, kidney, heart and muscle. In pigs, they have been detected in blood, spleen, liver kidney and in the GIT digesta. In poultry, traces have been seen in blood, liver and GIT digesta but not in meat and Eggs. Regardless of some studies that have shown the transfer of tDNA/protein fragments to animal samples, we cannot base on these few studies to give a piece of general evidence about their transfer into tissues/fluids and organs of livestock animals. However, this study clearly shows possible transfer, hence intensive and authentic research on GM crops should be done before they are allowed for commercial use, studying issues like the fate of tDNA or proteins and the effect of feeding GM feeds to livestock.
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Matovu, Jacob, e Ahmet Alçiçek. "Investigations and Concerns about the Fate of Transgenic DNA and Protein in Livestock". In International Students Science Congress. Izmir International Guest Student Association, 2021. http://dx.doi.org/10.52460/issc.2021.011.
Testo completoAbstract (sommario):
The fate of transgenic DNA (tDNA) and protein from feed derived from Genetically Modified organisms (GMOs) in animals has been a major issue since their commercialization in 1996. Several studies have investigated the risks of horizontal gene transfer (HGT) of tDNA and protein to bacteria or animal cells/tissues, but some of the reported data are controversial. Previous reports showed that tDNA fragments or proteins derived from GM plants could not be detected in tissues, fluids, or edible products from livestock. Other researchers have shown that there is a possibility of small fragments entering animal tissues, fluids and organs. This motivated us to update our knowledge about these concerns. Therefore, this review aimed to evaluate the probable transfer and accumulation of tDNA/proteins from transgenic feeds in animal samples (ruminant and non-ruminant) by evaluating the available experimental studies published scientifically. This study found that the tDNA/protein is not completely degraded during feed processing and digestion in Gastro-Intestinal Tract (GIT). In large ruminants (cattle), tDNA fragments/proteins were detected in GIT digesta, rumen fluid, and faeces. In small ruminants (goats), traces of tDNA/proteins were detected in GIT digesta, blood, milk, liver, kidney, heart and muscle. In pigs, they were detected in blood, spleen, liver, kidney, and GIT digesta. In poultry, traces were detected in blood, liver and GIT digesta but not in meat and eggs. Notwithstanding some studies that have shown transfer of tDNA/protein fragments in animal samples, we cannot rely on these few studies to give general evidence for transfer into tissues/fluids and organs of farm animals. However, this study clearly shows that transfer is possible. Therefore, intensive and authentic research should be conducted on GM plants before they are approved for commercial use, investigating issues such as the fate of tDNA or proteins and the effects of feeding GM feed to livestock.
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Niyonshuti, Eric, e Figen Kırkpınar. "Assessment of the Last Decades Studies and Developments in Broilers Nutrition". In International Students Science Congress. Izmir International Guest Student Association, 2021. http://dx.doi.org/10.52460/issc.2021.003.
Testo completoAbstract (sommario):
The poultry industry has advanced remarkably over the past 30 years. In particular, broiler production has been the most successful than any other sector in the animal industry. Production standards of broilers have continuously improved over this period, with modern broilers reaching a live average weight of 2.5 kg at 33 – 35 days. Today, under normal conditions, a broiler chicken can gain an average weight of 65 g per day and can attain 1.5 feed conversion ratio (FCR). Genetic selection brought about by breeding companies has played a big part in the improvements of broiler growth, and advances in nutritional management have provided about 10 to 15% of these changes. In conclusion, future broiler nutrition studies are going to be continued on the plane of economic criteria, determination of alternative feedstuffs and their cultivation, production of new feed additives, sustainability, and food or product quality. However, broiler nutrition studies are expected to contain not only pure and applied nutrition but also to answer and to enlighten some discussed issues such as to support animal welfare, consumer health, and ecological equilibrium. In this review, the latest improvements in feed formulation with much attention on metabolizable energy (ME) and crude protein (CP), feeding systems and feed presentation, use of feed additives to enhance feed use and broiler performance are discussed.
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Hachemi, Rabie, Nicolas Loménie e Nicole Vincent. "Discriminating poultry feeds by image analysis for the purpose of avoiding importunate poultry behaviors". In IS&T/SPIE Electronic Imaging, a cura di Kurt S. Niel e David Fofi. SPIE, 2009. http://dx.doi.org/10.1117/12.806006.
Testo completoRapporti di organizzazioni sul tema "Poultry Feeding and feeds"
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Uni, Zehava, e Peter Ferket. Enhancement of development of broilers and poults by in ovo feeding. United States Department of Agriculture, maggio 2006. http://dx.doi.org/10.32747/2006.7695878.bard.
Testo completoAbstract (sommario):
The specific objectives of this research were the study of the physical and nutritional properties of the In Ovo Feeding (IOF) solution (i.e. theosmostic properties and the carbohydrate: protein ratio composition). Then, using the optimal solution for determining its effect on hatchability, early nutritional status and intestinal development of broilers and turkey during the last quarter of incubation through to 7 days post-hatch (i.e. pre-post hatch period) by using molecular, biochemical and histological tools. The objective for the last research phase was the determination of the effect of in ovo feeding on growth performance and economically valuable production traits of broiler and turkey flocks reared under practical commercial conditions. The few days before- and- after hatch is a critical period for the development and survival of commercial broilers and turkeys. During this period chicks make the metabolic and physiological transition from egg nutriture (i.e. yolk) to exogenous feed. Late-term embryos and hatchlings may suffer a low glycogen status, especially when oxygen availability to the embryo is limited by low egg conductance or poor incubator ventilation. Much of the glycogen reserve in the late-term chicken embryo is utilized for hatching. Subsequently, the chick must rebuild that glycogen reserve by gluconeogenesis from body protein (mostly from the breast muscle) to support post-hatch thermoregulation and survival until the chicks are able to consume and utilize dietary nutrients. Immediately post-hatch, the chick draws from its limited body reserves and undergoes rapid physical and functional development of the gastrointestinal tract (GIT) in order to digest feed and assimilate nutrients. Because the intestine is the nutrient primary supply organ, the sooner it achieves this functional capacity, the sooner the young bird can utilize dietary nutrients and efficiently grow at its genetic potential and resist infectious and metabolic disease. Feeding the embryo when they consume the amniotic fluid (IOF idea and method) showed accelerated enteric development and elevated capacity to digest nutrients. By injecting a feeding solution into the embryonic amnion, the embryo naturally consume supplemental nutrients orally before hatching. This stimulates intestinal development to start earlier as was exhibited by elevated gene expression of several functional genes (brush border enzymes an transporters , elvated surface area, elevated mucin production . Moreover, supplying supplemental nutrients at a critical developmental stage by this in ovo feeding technology improves the hatchling’s nutritional status. In comparison to controls, administration of 1 ml of in ovo feeding solution, containing dextrin, maltose, sucrose and amino acids, into the amnion of the broiler embryo increased dramatically total liver glycogen in broilers and in turkeys in the pre-hatch period. In addition, an elevated relative breast muscle size (% of broiler BW) was observed in IOF chicks to be 6.5% greater at hatch and 7 days post-hatch in comparison to controls. Experiment have shown that IOF broilers and turkeys increased hatchling weights by 3% to 7% (P<0.05) over non injected controls. These responses depend upon the strain, the breeder hen age and in ovo feed composition. The weight advantage observed during the first week after hatch was found to be sustained at least through 35 days of age. Currently, research is done in order to adopt the knowledge for commercial practice.
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Koziel, Jacek, Yael Laor, Jeffrey Zimmerman, Robert Armon, Steven Hoff e Uzi Ravid. Simultaneous Treatment of Odorants and Pathogens Emitted from Confined Animal Feeding Operations (CAFOs) by Advanced Oxidation Technologies. United States Department of Agriculture, gennaio 2009. http://dx.doi.org/10.32747/2009.7592646.bard.
Testo completoAbstract (sommario):
A feasibility study was conducted, aiming to explore the potential effectiveness of UV/TiO2/O3 photooxidation technologies for simultaneous treatment of odorant and pathogen emissions from livestock and poultry operations. Several key parameters were tested in laboratory (US) and semi-pilot (Israel) scale conditions including: the effects of light energy dose (treatment time and light intensity), relative humidity and air temperature, UV wavelength, presence of photocatalyst (TiO2) and the presence of ozone. Removal and conversion of odor, target gases (sulfur-containing volatile organic compounds S-VOCs, volatile fatty acids (VFAs), phenolics, and ammonia), and airborne pathogens was tested. Up to 100% removal (below method detection level) of S-VOCs, VFAs, and phenolics, the overall odor, and up to 64.5% of ammonia was achieved with optimized treatment. Treatments involving deep UV band (185 nm) and photocatalyst (TiO2) were more efficient in removal/conversion of odorous gases and odor. The estimate of the operational cost of treatment was based on measured emissions of several odorous VOCs from full scale, commercial swine farm ranges from $0.15 to $0.59 per finisher pig. This figure represents significantly lower cost compared with the cost of biofiltration or air scrubbing.
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Mitchell, Brian G., Amir Neori, Charles Yarish, D. Allen Davis, Tzachi Samocha e Lior Guttman. The use of aquaculture effluents in spray culture for the production of high protein macroalgae for shrimp aqua-feeds. United States Department of Agriculture, gennaio 2013. http://dx.doi.org/10.32747/2013.7597934.bard.
Testo completoAbstract (sommario):
The FAO has projected a doubling in world demand for seafood during the 21 ed from aquaculture of marine fish and shrimps fed primarily on fishmeal-based aquafeeds. However, current practices of high intensity monoculture of shrimp in coastal ponds and fish in offshore pens have been strongly criticized as being ecologically and socially unsustainable. This view derives from un- checked eutrophication of coastal marine ecosystems from fish farm effluents, and the destruction of coastal estuarine ecosystems by shrimp farm constructions, plus aquaculture’s reliance on wild-caught small fish - which are excellent food for humans, but instead are rendered into fishmeal and fish oil for formulating aquafeeds. Fishmeal-sparing and waste- reduction aquafeeds can only delay the time when fed aquaculture product are priced out of affordability for most consumers. Additionally, replacement of fishmeal protein and fish oil by terrestrial plant sources such as soybean meal and oil directly raises food costs for human communities in developing nations. New formulations incorporating sustainably-produced marine algal proteins and oils are growing in acceptance as viable and practical alternatives. This BARD collaborative research project investigated a sustainable water-sparing spray/drip culture method for producing high-protein marine macrophyte meals for incorporation into marine shrimp and fish diets. The spray culture work was conducted at laboratory-scale in the USA (UCSD-SIO) using selected Gracilariaand Ulvastrains isolated and supplied by UCONN, and outdoors at pilot-scale in Israel (IOLR-NCM) using local strains of Ulvasp., and nitrogen/phosphorus-enriched fish farm effluent to fertilize the spray cultures and produce seaweed biomass and meals containing up to 27% raw protein (dry weight content). Auburn University (USA) in consultation with TAMUS (USA) used the IOLR meals to formulate diets and conduct marine shrimp feeding trials, which resulted in mixed outcomes, indicating further work was needed to chemically identify and remove anti-nutritional elements present in the IOLR-produced seaweed meals.
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Wong, E. A., e Z. Uni. Modulating intestinal cellular maturation and differentiation in broilers by in ovo feeding. Israel: United States-Israel Binational Agricultural Research and Development Fund, 2018. http://dx.doi.org/10.32747/2018.8134161.bard.
Testo completoAbstract (sommario):
Mortality in a broiler flock will typically range from 4-5% of the population over the course of 6- 7 weeks in the U.S. and 7-8% of the population in Israel. Suboptimal intestinal maturation and functionality are one of the major factors that contribute to early age mortality and hinder flock body weight uniformity. The development of absorptive and secretory functions is orchestrated by differentiation of cells that arise from stem cells. Supplying compounds by in ovo feeding (IOF) during late embryogenesis provides nutrients that may change the dynamics of stem cell differentiation. We hypothesize that the introduction of specific nutrients or probiotics to the late embryonic chick via IOF will result in an acceleration of the maturation of the small intestine as measured by villus/crypt morphology and the number and distribution of absorptive and secretory cells. A chick that can absorb nutrients more efficiently by increasing the number of cells expressing nutrient transporters and resist enteric pathogens by increasing the number of cells expressing mucin and host defense peptides will be healthier at hatch. This chick may have less need for antibiotics and may show reduced early mortality. The objectives of this proposal are to: 1) develop a model for the development of putative stem cells and absorptive/secretory cells in the small intestine of the late embryonic and early post hatch broiler. 2) determine the ability of IOF of nutrients to modulate the population of differentiated cells in the intestine. 3) determine the ability of IOF of probiotics to modulate the population of differentiated cells in the intestine. 4) reduce early mortality and increase body weight uniformity by IOF of selected nutrients or probiotics. This proposal combines the IOF expertise of Zehava Uni (Hebrew University) with the RNAscope in situ hybridization technique of Eric Wong (Virginia Tech). Previous studies using quantitative PCR to examine expression of genes in the intestine were unable to identify specific cells expressing these genes. RNAscope allows the ability to identify putative stem, absorptive and secretory cells in the small intestine. Thus, we will be able to investigate the effect of IOF on the presence of intestinal absorptive and secretory cells at the cellular level. Understanding the mechanisms for intestinal development and function are key to maintaining peak growth and health of chickens and thus would be of great economic benefit to the poultry industry.
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Lahav, Ori, Albert Heber e David Broday. Elimination of emissions of ammonia and hydrogen sulfide from confined animal and feeding operations (CAFO) using an adsorption/liquid-redox process with biological regeneration. United States Department of Agriculture, marzo 2008. http://dx.doi.org/10.32747/2008.7695589.bard.
Testo completoAbstract (sommario):
The project was originally aimed at investigating and developing new efficient methods for cost effective removal of ammonia (NH₃) and hydrogen sulfide (H₂S) from Concentrated Animal Feeding Operations (CAFO), in particular broiler and laying houses (NH₃) and hog houses (H₂S). In both cases, the principal idea was to design and operate a dedicated air collection system that would be used for the treatment of the gases, and that would work independently from the general ventilation system. The advantages envisaged: (1) if collected at a point close to the source of generation, pollutants would arrive at the treatment system at higher concentrations; (2) the air in the vicinity of the animals would be cleaner, a fact that would promote animal growth rates; and (3) collection efficiency would be improved and adverse environmental impact reduced. For practical reasons, the project was divided in two: one effort concentrated on NH₃₍g₎ removal from chicken houses and another on H₂S₍g₎ removal from hog houses. NH₃₍g₎ removal: a novel approach was developed to reduce ammonia emissions from CAFOs in general, and poultry houses in particular. Air sucked by the dedicated air capturing system from close to the litter was shown to have NH₃₍g₎ concentrations an order of magnitude higher than at the vents of the ventilation system. The NH₃₍g₎ rich waste air was conveyed to an acidic (0<pH<~5) bubble column reactor where NH₃ was converted to NH₄⁺. The reactor operated in batch mode, starting at pH 0 and was switched to a new acidic absorption solution just before NH₃₍g₎ breakthrough occurred, at pH ~5. Experiments with a wide range of NH₃₍g₎ concentrations showed that the absorption efficiency was practically 100% throughout the process as long as the face velocity was below 4 cm/s. The potential advantages of the method include high absorption efficiency, lower NH₃₍g₎ concentrations in the vicinity of the birds, generation of a valuable product and the separation between the ventilation and ammonia treatment systems. A small scale pilot operation conducted for 5 weeks in a broiler house showed the approach to be technically feasible. H₂S₍g₎ removal: The main goal of this part was to develop a specific treatment process for minimizing H₂S₍g₎ emissions from hog houses. The proposed process consists of three units: In the 1ˢᵗ H₂S₍g₎ is absorbed into an acidic (pH<2) ferric iron solution and oxidized by Fe(III) to S⁰ in a bubble column reactor. In parallel, Fe(III) is reduced to Fe(II). In the 2ⁿᵈ unit Fe(II) is bio-oxidized back to Fe(III) by Acidithiobacillus ferrooxidans (AF).In the 3ʳᵈ unit S⁰ is separated from solution in a gravity settler. The work focused on three sub-processes: the kinetics of H₂S absorption into a ferric solution at low pH, the kinetics of Fe²⁺ oxidation by AF and the factors that affect ferric iron precipitation (a main obstacle for a continuous operation of the process) under the operational conditions. H₂S removal efficiency was found higher at a higher Fe(III) concentration and also higher for higher H₂S₍g₎ concentrations and lower flow rates of the treated air. The rate limiting step of the H₂S reactive absorption was found to be the chemical reaction rather than the transition from gas to liquid phase. H₂S₍g₎ removal efficiency of >95% was recorded with Fe(III) concentration of 9 g/L using typical AFO air compositions. The 2ⁿᵈ part of the work focused on kinetics of Fe(II) oxidation by AF. A new lab technique was developed for determining the kinetic equation and kinetic parameters (KS, Kₚ and mₘₐₓ) for the bacteria. The 3ʳᵈ part focused on iron oxide precipitation under the operational conditions. It was found that at lower pH (1.5) jarosite accumulation is slower and that the performance of the AF at this pH was sufficient for successive operation of the proposed process at the H₂S fluxes predicted from AFOs. A laboratory-scale test was carried out at Purdue University on the use of the integrated system for simultaneous hydrogen sulfide removal from a H₂S bubble column filled with ferric sulfate solution and biological regeneration of ferric ions in a packed column immobilized with enriched AFbacteria. Results demonstrated the technical feasibility of the integrated system for H₂S removal and simultaneous biological regeneration of Fe(III) for potential continuous treatment of H₂S released from CAFO. NH₃ and H₂S gradient measurements at egg layer and swine barns were conducted in winter and summer at Purdue. Results showed high potential to concentrate NH₃ and H₂S in hog buildings, and NH₃ in layer houses. H₂S emissions from layer houses were too low for a significant gradient. An NH₃ capturing system was designed and tested in a 100-chicken broiler room. Five bell-type collecting devices were installed over the litter to collect NH₃ emissions. While the air extraction system moved only 10% of the total room ventilation airflow rate, the fraction of total ammonia removed was 18%, because of the higher concentration air taken from near the litter. The system demonstrated the potential to reduce emissions from broiler facilities and to concentrate the NH₃ effluent for use in an emission control system. In summary, the project laid a solid foundation for the implementation of both processes, and also resulted in a significant scientific contribution related to AF kinetic studies and ferrous analytical measurements.
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Ground-water quality and effects of poultry confined animal feeding operations on shallow ground water, upper Shoal Creek basin, Southwest Missouri, 2000. US Geological Survey, 2002. http://dx.doi.org/10.3133/wri024125.
Testo completo