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Hossain, Md Iqbal, Badhan Saha, Mahmuda Begum, Nusrat Jahan Punom, Mst Khadiza Begum y Mohammad Shamsur Rahman. "Bioaccumulation of heavy metals in Nile tilapia Oreochromis niloticus (Linnaeus 1758) fed with commercial fish feeds". Bangladesh Journal of Scientific Research 29, n.º 2 (4 de mayo de 2017): 89–99. http://dx.doi.org/10.3329/bjsr.v29i2.32325.
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The study was carried out to determine the concentration of heavy metals in some commonly used commercial fish feeds and to observe the bioaccumulation of Cr, Cu, Cd and Ni in liver, muscle and gills of tilapia Oreochromis niloticus after culturing them for 60 days by feeding those commercial feeds. The study revealed that the concentration of Cu was the highest (65.08 mg/kg) in handmade feed (B1) among four heavy metals. The concentrations of Cr in collected feeds were 1.75 to 3.04 mg/kg, which exceeds the permissible limit set by FAO. In cultured tilapia, the concentrations of studied heavy metals were found higher than initial concentration in fish feeds and in tilapia fingerlings. Metal levels in cultured fish followed the ranking of Cu>Cr>Ni>Cd and order in individual organs was liver>gill>muscle. The highest concentration of Cu (72.86 mg/kg) was found in liver given S feed and the lowest concentration (0.67 mg/kg) was in muscle receiving Q feed. Bioaccumulation of Cr was the highest (23.95 mg/kg) in liver taken B1 feed and the lowest (9.29 mg/kg) in muscle of tilapia cultured with C feed. Concentration of Cu exceeded the tolerable limit in fishes cultured with S and C feeds. But Cr concentration surpassed the allowable limit in every feed studied. The concentrations of Ni and Cd were below the permissible range approved by FAO. Considering the present study, tilapia cultured with these experimental feeds is not safe for human consumption. Higher concentration of these heavy metals exceeding allowable limit may cause harmful effect on human body after consumption of those fishes and can create cancer and other diseases in human body.Bangladesh J. Sci. Res. 29(2): 89-99, December-2016
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Jackson, Dorothy A., Stella M. Imong, A. Silprasert, S. Ruckphaopunt, M. W. Woolridge, J. D. Baum y K. Amatayakul. "Circadian variation in fat concentration of breast-milk in a rural northern Thai population". British Journal of Nutrition 59, n.º 3 (mayo de 1988): 349–63. http://dx.doi.org/10.1079/bjn19880044.
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1. Twenty-five northern Thai mothers, breast-feeding their infants on demand, were studied in their homes for 24 h. All breast-feeds were test-weighed and pre- and post-feed expressed breast-milk samples (0·5 ml) taken at each feed.2. The fat concentration of milk taken during a feed showed significant circadian variation, with maximum values between 16.00 and 20.00 hours and minimum values between 04.00 and 08.00 hours. Fat concentration at the start and at the end of a feed also varied significantly over 24 h.3. Multiple regression analysis showed that the most important predictor of fat concentration at a feed was the length of time elapsed since the previous feed – the longer this interval, the lower the subsequent fat concentration. Other significant predictors were the fat concentration at the end of the previous feed, and the milk intake at the previous and at the current feed.4. Fat concentration declined between feeds in proportion to the length of time between feeds, but the decline was less between sleep feeds than between waking feeds. This would appear to be a reflection of the lower post-feed fat concentration and higher pre-feed fat concentration of sleep feeds compared with waking feeds, when other variables relating to feeding pattern are taken into account.5. The larger the milk intake at a feed, the greater was the increase in fat concentration from the start to the end of the feed. The change in fat concentration was less in feeds taking place during the sleep period than in daytime feeds.
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Islam, M. M., S. M. L. Kabir, Y. A. Sarker, M. M. H. Sikder, S. K. S. Islam, A. H. M. T. Akhter y M. M. Hossain. "RISK ASSESSMENT OF CHROMIUM LEVELS IN BROILER FEEDS AND MEATS FROM SELECTED FARMS OF BANGLADESH". Bangladesh Journal of Veterinary Medicine 14, n.º 2 (3 de febrero de 2017): 131–34. http://dx.doi.org/10.3329/bjvm.v14i2.31381.
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The present study was conducted to evaluate the status of chromium concentration in broiler feeds with the risk assessment of chromium in broiler meat. Seven broiler farms were selected to collect the feed and meat samples of broiler. Atomic absorption spectrophotometer (AAS) was used to determine the chromium concentration in broiler feed and meat samples. The highest concentration of chromium in broiler meat samples was 1.31±0.20 ?g/g and in feed samples was 1.71±0.24?g/g. In this study, the mean (± SE) concentration of chromium in feed samples from Gazipur Sadar, Gazipur; Sreepur, Gazipur and Tangail Sadar, Tangail were 1.71(± 0.24) ?g/g,1.64(±0.61) ?g/g and 1.64(±0.61) ?g/g respectively. The mean (± SE) concentration of chromium in meat samples from Gazipur Sadar, Gazipur; Sreepur, Gazipur and Tangail Sadar, Tangail were 1.139 (±0.26) ?g/g, 1.31 (±0.20) ?g/g and 0.61 (±0.23) ?g/g respectively. The concentrations of chromium in broiler edible tissues were much higher than permissible levels determined by FAO and WHO. Precocious steps must be taken to avoid use of such health hazardous concentrations of heavy metals in poultry feeds. Considering these findings, there is a critical need to set legal limits and surveillance system for detection of heavy metals in poultry industry of Bangladesh.
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Dickinson, P. W. "Pre-concentration of feed stock". Journal of Heat Recovery Systems 6, n.º 1 (enero de 1986): 67–71. http://dx.doi.org/10.1016/0198-7593(86)90173-6.
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Rafai, Pál, Zoltán Papp y László Jakab. "Biotransformation of trichothecenes alleviates the negative effects of T-2 toxin in pigs". Acta Veterinaria Hungarica 61, n.º 3 (1 de septiembre de 2013): 333–43. http://dx.doi.org/10.1556/avet.2013.025.
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Between 49 and 70 days of age, three groups of growing pigs (n = 10 each) were fed diets containing 0, 0.3 and 0.5 mg/kg T-2 toxin, respectively, for 21 days. The feed of another two groups of pigs (n = 10 each) contained 0.3 or 0.5 mg/kg T-2 toxin, respectively, plus a feed additive developed for splitting up the molecular structure of Fusarium toxins, in particular trichothecenes, by deepoxidation of the molecule, at 2 kg/tonne concentration. One group (n = 10) served as positive control; their feed was free from T-2 toxin but contained the feed additive at the above concentration. Toxin concentrations at these low dietary levels impaired the feed intake and growth rate of pigs. The feed additive alleviated the negative effects and justified its potential for prevention. Data of the present study indicated a 0.2 mg/kg feed no observed effect level (NOEL) of T-2 toxin in growing pig feeds.
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Fairley, R. A. C., S. P. Rose y M. F. Fuller. "Selection of dietary lysine and threonine concentration of growing pigs". Proceedings of the British Society of Animal Production (1972) 1993 (marzo de 1993): 195. http://dx.doi.org/10.1017/s0308229600025174.
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The aim of these trials was to discover if growing pigs can select an appropriate mixture of two feeds differing only in the level of one amino acid.A trial was conducted with 40 male pigs, with an initial mean weight of 13.1 kg. A basal low lysine feed was formulated with 172 g digestible protein (DP)/kg feed which was supplemented with synthetic lysine. The resulting feeds were similar in all respects except digestible lysine (DL) level, which was 25 (L), 50 (ML), 109 (MH) and 141 (H) g/kg DP.A second trial was carried out with threonine, using 48 male pigs with an initial mean weight of 11.94 kg. The same basal feed was supplemented with synthetic lysine to 70 g DL/kg DP and then supplemented with varying amounts of synthetic threonine to form four feeds with digestible threonine (DT) levels of 29 (L), 35 (ML), 55 (MH) and 68 (H) g/kg DP.
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Olatoye, O. I., J. O. Aiyedun y O. O. Oludairo. "Incidence of Aflatoxin B1 in Commercial Poultry Feed and Tissues of Broiler Chickens in Ibadan, Nigeria". Sahel Journal of Veterinary Sciences 17, n.º 2 (29 de junio de 2020): 13–18. http://dx.doi.org/10.54058/saheljvs.v17i2.87.
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Aflatoxin B1 (AFB1) belongs to a group of hepatocarcinogenic and hepatotoxic mycotoxin produced by Aspergillus flavus and Aspergillus parasiticus found in food or feed products. In this study we analyzed 180 feed of six different brands of commercial poultry feeds from three feed distribution outlets in Ibadan, southwest Nigeria for the occurrence and concentrations of AFB1. In addition, to the transfer of AFB1 to broiler meat from chicken fed for four weeks with one brand of feed associated with the highest AFB1 contamination. The study was carried out between April and June, 2019. The presence/concentration of AFB1 was determined using High Performance Liquid Chromatography (HPLC) following solid phase extraction of sample and preparation. Aflatoxin B1 was detected in all (100 %) the brands of feed and 48 % of chicken samples tested. The concentration of AFB1 in feed ranged between 10.5 ± 4.0 and 47.78 ± 6.4, while the mean AFB1 residues obtained in chicken muscle, gizzards and liver after four weeks were 0.07 ± 0.02, 0.18 ± 0.05 and 0.13 ± 0.02 μg/kg, respectively. The presence of AFB1 in all the brands of poultry feeds tested in this study and its possible transfer into chicken meat poses food/feed safety and public health concern. There is therefore, the need to screen feed and apply Hazard Analysis Critical Control Point to feed manufacturing, storage and broiler chicken production to prevent aflatoxicosis.
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Fajar, Muhammad Thoifur. "Pengaruh Perbedaan Konsentrasi Pakan Pelet Terhadap Bobot Dan Panjang Ikan Mas (Cyprinus Carpio)". INSOLOGI: Jurnal Sains dan Teknologi 1, n.º 5 (29 de octubre de 2022): 498–504. http://dx.doi.org/10.55123/insologi.v1i5.801.
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Pellet feed is feed that is commonly used for the cultivation of livestock, namely broiler chickens, birds, hamsters, rabbits, fish and shrimp. Carp (Cyprinus carpio) is a fish that is often cultivated because it has economic opportunities and increasing demand. This study aims to determine the growth in length and weight of carp with pellet feeding. The research was conducted at the Basic Science Laboratory of UNARS campus 2 in July and August 2022. The method of observing the length and weight of carp using descriptive analysis method. The goldfish samples tested were 3 groups with 3 goldfish in each group. Groups of carp A, B and C were given different pellet feed treatments with pellet feed concentrations of 3%, 4% and 5% of the weight of the carp group. The results showed that pelleted feed with a concentration of 4% of carp B group added the highest weight of carp compared to feed with a concentration of 3% of carp A group and feed of 5% concentration of carp C group. The highest absolute length growth was seen in feed with 3% concentration of group A compared to feed with a concentration of 3% of group A. 4% concentration feed group B and 5% concentration feed group C
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Hyslop, J. J., B. M. L. McLean y M. J. S. Moore-Colyer. "Relationship between water holding capacity and fibre concentration in equine feeds". BSAP Occasional Publication 32 (2004): 233–37. http://dx.doi.org/10.1017/s0263967x00041550.
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The water content of feedstuffs is an important factor when considering both the nutritive value of a feed for dietary rationing purposes and when assessing the functional properties associated with the practical inclusion of a feedstuff in animal diets. Water is a vital nutrient in its own right and must be supplied on a daily basis. Feed associated water provides one source of this obligatory requirement. In addition, the water holding capacity (WHC) of a feedstuff and its relationship with other constituents of the feed may have important effects. Water can be associated with feedstuff in one of three ways (Robertson and Eastwood, 1981b). Firstly, water can be bound by the hydrophilic polysaccharides of the fibre component of feeds. Secondly, water can be held within the structural fibre matrix of feeds and finally, water can be associated with feedstuff fibre other than bound or matrix water and is usually considered as water trapped within the cell wall lumen.
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Vandael, Femke, Helena Cardoso de Carvalho Ferreira, Mathias Devreese, Jeroen Dewulf, Els Daeseleire, Mia Eeckhout y Siska Croubels. "Stability, Homogeneity and Carry-Over of Amoxicillin, Doxycycline, Florfenicol and Flubendazole in Medicated Feed and Drinking Water on 24 Pig Farms". Antibiotics 9, n.º 9 (31 de agosto de 2020): 563. http://dx.doi.org/10.3390/antibiotics9090563.
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The vast majority of medicines in pig rearing are administered via oral group medication through medicated feed and drinking water. However, relevant on-farm factors affecting the concentration of these drugs in feed and drinking water, such as the homogeneity, stability, and cross-contamination, are largely unknown. To characterize these factors, samples of medicated feed and drinking water were taken on 24 Belgian pig farms during treatment and 2 days thereafter, as well as at different on-farm sampling sites from production to feeding troughs or drinking nipples. The samples contained amoxicillin, doxycycline, florfenicol, or flubendazole. Additionally, a questionnaire was completed. In contrast to the results of medicated feed, results of medicated water showed a large between-farm variation in antimicrobial drug concentration. The therapeutic concentration range was only met in 2 out of 11 farms using medicated feed, and in 3 out of 13 farms using medicated water. Medicated feed concentrations were often below the therapeutic concentration range mentioned in the Summary of Product Characteristics, while drinking water concentrations were just as often above as they were below the advised target concentration range. Drug residues measured 2 days after the end of therapy with both feed and water medication rarely exceeded 1% of the lowest therapeutic concentration. This study demonstrates that recommendations on good clinical practices for oral group medication in the pig industry are highly needed.
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Jackson, Dorothy A., Stella M. Imong, A. Silprasert, S. Preunglumpoo, P. Leelapat, Y. Yootabootr, K. Amatayakul y J. D. Baum. "Estimation of 24 h breast-milk fat concentration and fat intake in rural northern Thailand". British Journal of Nutrition 59, n.º 3 (mayo de 1988): 365–71. http://dx.doi.org/10.1079/bjn19880045.
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1. The present study assesses the accuracy with which mean 24 h breast-milk composition can be estimated if milk samples can only be collected during the daytime.2. Twenty-five northern Thai mothers, feeding their infants on demand, were studied in their homes for 24 h. All feeds were test-weighed and 0·5 ml pre- and post-feed expressed milk samples taken at each feed.3. If daytime sampling was restricted to two breast-feeds, it was found that the best estimate of 24 h fat concentration was given by two randomly chosen daytime feeds, predicting 24 h fat concentration with 95% confidence limits of ±7·0 g/l (equivalent to 21% of mean 24 h fat concentration).4. Alternative sampling methods using the mean fat concentration of the feed after 08·00 hours and after 18·00 hours, or the first two feeds after 12·00 hours, predicted fat concentration with 95% confidence limits of ±9·7 g/l and ±8·9 g/l (28 and 26% of mean 24 h fat concentration) respectively.5. If well-tolerated by mothers, it would be preferable to sample all daytime feeds, since this reduces the 95% confidence limits to ±3·3 g/l, equivalent to 10% of the mean 24 h fat concentration.
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Fatema, Kaniz, Md Nazmus Sakib, Md Al Zahid, Nahid Sultana y Md Rakibul Hassan. "Growth performances and bioaccumulation of heavy metals in Anabas testudineus (Bloch, 1792) cultured using different market feeds". Bangladesh Journal of Zoology 47, n.º 1 (27 de junio de 2019): 77–88. http://dx.doi.org/10.3329/bjz.v47i1.42023.
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The study was conducted to determine growth performances and bioaccumulation of Cr, Cu, Cd, Pb and Ni in fish organs such as intestines, muscle and gills of study species after culturing them for twelve weeks by using different commercial fish feeds. The highest average daily gain (ADG, g/day) and specific growth rate (SGR; %/day) were found in fish fed quality feed and lowest values were found in the fish fed mega feed. Best feed conversion ratio (FCR) value was found in fish fed quality feed among five different feeds. In cultured Koi, the concentration of heavy metals were found higher than initial concentration in fish feeds and collected fingerling samples. Heavy metal levels in cultured fish was Cu > Pb > Cr > Cd > Ni and levels of bioaccumulation in individual organs was intestines > gills > muscle. The concentration of Cu, Pb and Cr exceed the tolerable limit approved by FAO in fishes cultured with the experimental feeds. Considering the present study, Koi cultured with these experimental feeds may not safe for human consumption.
Bangladesh J. Zool. 47(1): 77-88, 2019
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Weston, RH. "Factors limiting the intake of feed by sheep. 15. Voluntary feed consumption and digestion in lambs fed chopped roughage diets varying in quality". Australian Journal of Agricultural Research 40, n.º 3 (1989): 643. http://dx.doi.org/10.1071/ar9890643.
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Feed intake and digestion transactions for diets based on wheaten straw and mature ryegrass diets, both supplemented to provide additional essential nutrients, were compared with those for lucerne hay and high quality forage oats diets in lambs weighing c. 24 kg. The data obtained and comparable published data were used to examine relationships between a range of variables. Decrease in roughage quality, as evidenced by decrease in digestible organic matter (OM) intake, was accompanied by increase in (i) times spent eating, ruminating and chewing rumination boluses, (ii) the quantities of digesta or digesta OM in the reticula-rumen and omasum. It was not associated with increase in the large particle content of rumen or omasum digesta. Over the range of diets, close direct relations were demonstrated between (i) ruminating time and the amount of digesta in the reticulo-rumen, (ii) the amounts of digesta in the reticulo-rumen and omasum, (iii) the OM concentrations in rumen and reticulum digesta, (iv) the OM concentrations in reticulum and omasum digesta, (v) the OM concentration of reticulum digesta and of digesta flowing to the omasum, and (vi) the increase in OM concentration from reticulum to omasum digesta and OM concentration of reticulum digesta. Reticulum digesta were of finer texture than rumen digesta, and the bulk density of digesta particle fractions varied between diets, and sometimes between rumen and large intestine digesta. With a straw-based diet, relative to lucerne hay, small particles ( <600 �m sieve) were cleared more slowly from the reticula-rumen, associated with a larger reticulo-rumen particle pool. The data are discussed in relation to (i) the flow of digesta through the alimentary tract and (ii) the regulation of roughage intake. They were considered to be consistent with a concept that energy metabolism and digesta load in the reticulo-rumen interact in the regulation of roughage intake.
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Gomes, Rodrigo da Costa, Renata Farinelli de Siqueira, Michael Alan Ballou, Tiago Roberto Stella y Paulo Roberto Leme. "Hematological profile of beef cattle with divergent residual feed intake, following feed deprivation". Pesquisa Agropecuária Brasileira 46, n.º 9 (septiembre de 2011): 1105–11. http://dx.doi.org/10.1590/s0100-204x2011000900019.
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The objective of this work was to characterize the hematological profiles of steers and bulls, according to residual feed intake (RFI), after feed deprivation. Twenty‑month‑old Nellore steers and bulls were fed feedlot diets for 70 and 56 days, respectively. RFI was calculated as the difference between actual feed intake and expected feed intake. More and less efficient steers and bulls, according to RFI, were subjected to 24 hours of food deprivation. Blood was sampled prior to and following the withdrawal period. Hematological analyses included total and differential white blood cell count, red blood cell count and morphology, and plasma glucose concentration. Variation in RFI did not influence plasma glucose concentration or blood cell profiles. Glucose concentrations in bulls decreased from 114 to 97 mg dL‑1, but remained unchanged in steers, and the neutrophil:lymphocyte ratio increased from 0.39 to 0.57 following deprivation. Hematological profiles do not differ between more and less efficient steers and bulls, according to RFI.
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Hassan, Assrar Abdullah y Hala Adel Jabbar. "Direct Contact Membrane Distillation for Separation of Hcl From A Mixture of Acids". Journal of Engineering 24, n.º 6 (1 de junio de 2018): 41. http://dx.doi.org/10.31026/j.eng.2018.06.04.
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HCl is separated from HCl –H2SO4 solution by membrane distillation process(MD). The flat –sheet membranes made from polyvinylidene fluoride (PVDF) and polypropylene (pp.). Plate and frame these types of membrane where used in the process. The feed is a mixture of HCl and H2SO4 acids compositions depended on metals treated object.HCl concentration increased in the permeate during the process but sulfuric acid increased gradually in the feed .During the concentration of solution acids concentrations in the feed at the beginning were 50 g/dm3 of sulfuric acid and 50 g/dm3 of hydrochloric acid at 333K feed temperature the permeate flux was 71 dm3/m2.d. At a higher concentration of HCl in the feed 111g /dm3 and 61 g/ dm3 of sulfuric acid at the feed temperature 333K volume permeate flux was 57 dm3/ m2.d . At a higher concentration of sulfuric acid in the feed 161 g/dm3 and 60 g/dm3 of HCl decrease the permeate flux from 71 to 35 dm3/m2.d at 333K . The permeate flux increase from 35 at 333K to 85 at 343 K increase the temperature caused an increase in permeate flux. Increases in sulfuric acid concentration from 50 to 161 g/dm3 decrease the volume permeate flux from 71 to 35 dm3 /m2.d, HCl concentration was achieved a higher value 9.1 g/dm3 during the process at the feed concentration 161g/dm3 of sulfuric acid and 60g/dm3 of hydrochloric acid at feed temperature 343K.
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Panne, C. y D. N. Srangeland. "THE OPTIMAL CONCENTRATION OF CATTLE FEED SUPPLEMENTS". Canadian Journal of Agricultural Economics/Revue canadienne d'agroeconomie 22, n.º 3 (13 de noviembre de 2008): 25–34. http://dx.doi.org/10.1111/j.1744-7976.1974.tb00933.x.
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Battaile, C. C., D. J. Srolovitz y J. E. Butler. "Point defect incorporation during diamond chemical vapor deposition". Journal of Materials Research 14, n.º 8 (agosto de 1999): 3439–46. http://dx.doi.org/10.1557/jmr.1999.0465.
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The incorporation of vacancies, H atoms, and sp2 bond defects into single-crystal homoepitaxial (100) (2 × 1)–and (111)-oriented chemical-vapor-deposited diamond was simulated by atomic-scale kinetic Monte Carlo. Simulations were performed for substrate temperatures from 600 to 1200 °C with 0.4% CH4 in the feed gas, and for 0.4–7% CH4 feeds with a substrate temperature of 800 °C. The concentrations of incorporated H atoms increased with increasing substrate temperature and feed gas composition, and sp2 bond trapping increased with increasing feed gas composition. Vacancy concentrations were low under all conditions. The ratio of growth rate to H atom concentration was highest around 800–900°C, and the growth rate to sp2 ratio was maximum around 1% CH4, suggesting that these conditions are ideal for economical diamond growth under simulated conditions.
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Pleadin, J., N. Persi, A. Vulic y M. Zadravec. "Survey of mycotoxin feed contamination in Croatia". Biotehnologija u stocarstvu 28, n.º 2 (2012): 167–77. http://dx.doi.org/10.2298/bah1202167p.
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The aim of this study was to investigate the contamination of feed with mycotoxins. A total of 103 samples of feed for poultry, pig and calves was collected at different animal feed factories in the central, eastern and north region of Croatia. The quantitative determination of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), fumonisins B1, B2 and B3 (FUM) and T-2 toxin (T-2) concentration was done using the validated ELISA method. The observed results indicated an increased contamination of pig feed with Fusarium mycotoxins DON and ZEA with mean concentrations of 1454?1444 ?g/kg and 153?161 ?g/kg, higher than recommended in 20% and 5% of the samples, respectively. Higher DON concentrations than recommended were also observed in 7% of calves feed with a mean concentration of 1140?1288 ?g/kg. The concentrations of AFB1, OTA and FUM in all the investigated samples in all country regions were according to the maximum allowed or recommended values in the European Union.
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Assis, Yhago Patrycky Antunes Souza, Anna Christina de Almeida, Wedson Carlos Lima Nogueira, Cintya Neves de Souza, Samuel Ferreira Gonçalves, Flavio Emanuel Gomes Silva, Vanessa Kelly Ferreira do Rosário Santos y Ernane Ronie Martins. "Antibacterial activity and stability of microencapsulated lemon grass essential oil in feeds for broiler chickens". Revista Brasileira de Saúde e Produção Animal 18, n.º 4 (diciembre de 2017): 587–93. http://dx.doi.org/10.1590/s1519-99402017000400009.
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SUMMARY The antibacterial effect of microencapsulated lemon grass (Cymbopogon citratus) essential oil on strains of Escherichia coli (ATCC8739), Staphylococcus aureus (ATCC 6538) and Salmonella enterica subsp. enterica (ATCC 6017), and the stability of this oil in feeds for broiler chickens were evaluated. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were determined by the macrodilution method, using the microencapsulated lemon grass essential oil at concentrations of 160 μL mL−1, 80 μL mL−1, 40 μL mL−1, 20 μL mL−1, and 10 μL mL−1. The oil concentration of 80 μL mL−1 presented the best results against the three bacteria evaluated. Samples of 200 g of feed mixed with 120 μL g−1 of the microencapsulated lemon grass essential oil was stored to evaluate the oil stability. Feed without microencapsulated lemon grass essential oil was prepared as control. The oil remained active for seven days, with significant reduction of S. aureus (3.08 CFU), E. coli (3.01 CFU), and S. enterica (3.10 CFU). The microencapsulated lemon grass essential oil at concentration of 80 μL mL−1 had antibacterial effect against the E. coli, S. enterica and S. aureus, and maintained stability of the feed for seven days, even with presence of organic matter, which is source of nutrients for pathogens.
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Ghoreishi, S. M., S. M. Shariatmadar Mortazavi y Ali Hedayati. "Modeling of Non-catalytic Supercritical Water Oxidation of Phenol". Chemical Product and Process Modeling 10, n.º 4 (1 de diciembre de 2015): 243–51. http://dx.doi.org/10.1515/cppm-2015-0044.
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Abstract The non-catalytic supercritical water oxidation (SCWO) of phenol was modeled using Gopalan-Savage and Thornton-Savage global and network rates. Comparison of experimental data for the phenol conversion with the numerical predictions of this study indicated very close compatibility. Applying the validated model, the phenol conversion and selectivity of various products were studied as a function of effective parameters such as feed phenol concentration, reactor residence time, feed temperature, and feed oxygen concentration. The results of modeling analysis show that an appropriate elevated temperature range (460°C < T <500°C) and long residence time (≈90 s) reduce the concentration of hazardous products (i.e., dimers, dibenzofuran, dibenzo-p-dioxin) and maximize the selectivity of environmental benign products such as water and carbon dioxide. Also, high oxygen concentration (≈0.01 mol/L) increase water and carbon dioxide yield. Moreover, high feed phenol concentrations cause a shortcoming for the SCWO system in terms of phenol conversion and selectivity of desirable environmental products. As a consequence, the feed phenol concentration of ≤2 × 10−3 mol/L is recommended as the appropriate condition.
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Roeva, N. N. y I. A. Zaitseva. "Analytical control of the content of radionuclides in feed". Upravlenie kachestvom (Quality management), n.º 2 (15 de enero de 2023): 7–11. http://dx.doi.org/10.33920/pro-01-2302-01.
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The authors determined the radionuclides Cs-137 and Sr-90 in the soils and feeds of the Khvastovichi and Maloyaroslavetsky districts of the Kaluga region, using the radiochemical method. Sample preparation and concentration of the analyzed samples was carried out by the method of "dry salting". It was found that in the studied soil and feed samples, the content of Ss-137 and Sr-90 does not exceed their maximum permissible concentrations.
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Lindén, Anna, Ing-Marie Olsson y Agneta Oskarsson. "Cadmium Levels in Feed Components and Kidneys of Growing/Finishing Pigs". Journal of AOAC INTERNATIONAL 82, n.º 6 (1 de noviembre de 1999): 1288–97. http://dx.doi.org/10.1093/jaoac/82.6.1288.
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Abstract Cadmium (Cd) concentrations in pig feeds (one control feed and one feed with reduced nitrogen content), straw, water, and pig kidney cortex were determined in 2 breeds of growing/finishing pigs (n = 96). The total Cd intake from feed was calculated. Feed mixtures and components, straw and kidney cortex samples, and certified reference samples were microwave-digested and analyzed by atomic absorption spectrometry with graphite furnace technique. Total Cd concentration in the control feed was 37.1 μg/kg wet weight (w.wt). The highest Cd levels were found in nonlocally produced feed components: vitamin-mineral mixture, lime, dicalcium phosphate, soybean meal, and rapeseed meal. These components contributed 70% of the Cd content in the feed. The main component, barley, which was locally produced, contributed 30% of the total Cd content in feed. The feed with reduced nitrogen content contained less soybean and rapeseed meal and a lower Cd level than the control feed. The Cd levels in kidney cortex varied from 38.0 to 105 μg/kg w.wt, with a mean level of 70.9 μg/kg. The levels differed between breeds and feeds, but not between gender. There was a significant correlation between Cd level in kidney cortex and age at slaughter, with an increase of 2.8 μg/kg w.wt in the kidney for each additional week of survival. The contribution of Cd from nonlocally produced feed components could have environmental effects through application of farmyard manure to local soils.
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Doherty, Stephen J., Allen Fox y David W. Fink. "Liquid Chromatographic Determination of Ivermectin in Feed". Journal of AOAC INTERNATIONAL 81, n.º 4 (1 de julio de 1998): 869–72. http://dx.doi.org/10.1093/jaoac/81.4.869.
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Abstract An analytical method for determining ivermectin in feed at 0.50- 3 ppm is presented. The method is based on liquid chromatographic measurement after sample preparation by adsorption chromatography on alumina and solid-phase extraction. Two complete, final, finished medicated feeds and the corresponding control feeds used in their preparation were analyzed. Recoveries from feeds fortified at 50-150% of the 2 ppm ivermectin use concentration also were determined. Mean recoveries from replicate analyses ranged from 90 to 100%, and coefficients of variation (CVs) were less than 4.5%. No significant interferences were found in control feeds. The pooled distribution of individual analytical results (n = 100) gave a mean recovery of 100%, a recovery range of 90-111%, and an overall CV of 5.5%. Resolution of the total variance into its 2 components gave a withinlaboratory CV of 4.1% and a between-laboratory CV of 3.4%. There was no significant difference in recoveries among laboratories, days, concentrations, and feed base or between fortified and medicated feeds (P > 0.2)
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Oddy, VH y PJ Holst. "Maternal-foetal adaptation to mid pregnancy feed restriction in single-bearing ewes". Australian Journal of Agricultural Research 42, n.º 6 (1991): 969. http://dx.doi.org/10.1071/ar9910969.
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In two experiments, restriction of feed to levels below maintenance for periods of up to 4 weeks was imposed on groups of ewes bearing single foetuses at 79, 87 or 95 days post coitus. In the first experiment, carried out at pasture, measurements were made of concentration of ovine placental lactogen (oPL) and progesterone in ewe plasma. Effects on lamb birth weight and gestation length were also examined. The second experiment investigated the effect of maternal feed restriction of (i) feed intake, (ii) maternal oPL, (iii) maternal plasma glucose concentration, (iv) lamb birth weight and (v) gestation length. In the first experiment, there were no significant effects of feed restriction on lamb birth weight or gestation length, although foetal growth rate had been reduced in some treatment groups. There were significant interactions between time of sampling and treatment for oPL and progesterone concentration. Control group ewes had lower oPL (P< 0.001) and progesterone (P < 0.05) concentrations than restricted ewes at the end of feed restriction, but higher oPL (P < 0.001) and progesterone (P <0.05) concentrations at 144 days post coitus. In the second experiment, lamb birth weight and gestation length were not significantly affected by maternal feed restriction (birth weight: restricted 4.94 kg, control 4.87 kg av. s.e.m. 0.17 kg; gestation length: restricted 148.3 days, control 147.0 days, av. s.e.m. 0.76 days). Feed restriction was associated with increased (P < 0.05) oPL and decreased glucose (P < 0.05) concentration in plasma. Maternal feed intake was significantly higher (P <0.05) in the restricted group in the week preceding lambing. These results strongly suggest that continuation of maternal feed intake over the last week of pregnancy is the major contributor to maintenance of 'normal' lamb birth weight in previously feed restricted ewes.
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Yambayamba, E. S. K., M. A. Price, J. L. Aalhus y S. D. M. Jones. "Glycogen metabolites and meat quality in feed-restricted re-fed beef heifers". Canadian Journal of Animal Science 76, n.º 4 (1 de diciembre de 1996): 517–22. http://dx.doi.org/10.4141/cjas96-078.
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Twenty-four Hereford crossbred heifers weighing 222 kg (22 kg SD) and aged 226 d (13 d SD) on day 0 were used to investigate the effects of feed restriction (period 1) followed by realimentation (period 2) on hepatic and longissimus muscle glycogen metabolites and meat quality. The heifers were randomly assigned in equal numbers to either ad libitum feeding (ADLIB) or maintenance feeding for 92 d followed by realimentation (REST), and serially slaughtered over a wide range of liveweights (200–460 kg). The concentrations of glycogen, its metabolites, and the total glucidic potential (GP) were determined from portions of the caudate lobe of the liver and the longissimus lumborum (LL) muscle. Meat quality assessment of the longissimus thoracis (LT) was done by objective means. Hepatic glycogen concentration was lower (P = 0.05) in REST than in ADLIB heifers, and GP tended to show a similar pattern (P = 0.07). There were no significant differences in the concentrations of glycogen or its metabolites in the LL of REST compared with ADLIB heifers. However, the heifers slaughtered during period 1 had lower muscle glycogen (P = 0.04) and higher lactate (P < 0.01) concentrations than those slaughtered during period 2. REST heifers had lighter slaughter weights resulting in smaller ribeye areas (P = 0.03), lower intramuscular fat concentration (P < 0.01) and higher moisture content (P < 0.01). Independent of slaughter weight, REST heifers had higher drip loss (P = 0.05) and lower L * (P = 0.01) than ADLIB heifers. These results suggest that feed restriction affects hepatic glycogen reserves and also has minor effects on meat quality traits in beef heifers. However, there was no indication that meat from REST heifers had severe quality defects such as DFD (dark, firm, dry) meat. Key words: Feed restriction, realimentation, longissimus muscle, liver, glucidic potential, meat quality
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Weiss, William P. y Alexander W. Tebbe. "Estimating digestible energy values of feeds and diets and integrating those values into net energy systems". Translational Animal Science 3, n.º 3 (5 de noviembre de 2018): 953–61. http://dx.doi.org/10.1093/tas/txy119.
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Abstract The California Net Energy System (CNES) used a combination of measured and tabular metabolizable energy (ME) values and changes in body composition gain to determine net energy requirements for maintenance and gain and their corresponding dietary concentrations. The accuracy of the CNES depends on the accuracy of the feed ME values. Feed or diet ME values can be measured directly but are expensive and require specialized facilities; therefore, most ME values are estimated from digestible energy (DE) values, which are often estimated from the concentration of total digestible nutrients (TDN). Both DE and TDN values are often from tables and not based on actual nutrient analysis. The use of tabular values eliminates important within-feed variation in composition and digestibility. Furthermore, the use of TDN to estimate DE does not account for important variation in the gross energy value of feeds. A better approach would be to estimate DE concentration directly from nutrient composition or in vitro (or in situ) digestibility measurements. This approach incorporates within-feed variation into the energy system and eliminates the issues of using TDN. A widely used summative equation based on the commonly measured feed fractions (ash, crude protein, neutral detergent fiber, and fat) has been shown to accurately estimate DE concentrations of many diets for cattle; however, deficiencies in that equation have been identified and include an overestimation of DE provided by fat and an exaggerated negative effect of intake on digestibility. Replacing the nonfiber carbohydrate term (which included everything that was not measured) in the equation with measured starch concentration and residual organic matter (i.e., nonfiber carbohydrate minus starch) should improve accuracy by accounting for more variation in starch digestibility. More accurate estimates of DE will improve the accuracy of ME values, which will ultimately lead to more accurate NE values.
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Ojumu, Tunde Victor y Jochen Petersen. "Kinetics of Microbial Ferrous-Iron Oxidation by Leptospirillum Ferriphilum: Effect of Ferric-Iron on Biomass Growth". Advanced Materials Research 71-73 (mayo de 2009): 259–62. http://dx.doi.org/10.4028/www.scientific.net/amr.71-73.259.
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The kinetics of microbial ferrous-iron oxidation have been well studied as it is a critical sub-process in bioleaching of sulphide minerals. Exhaustive studies in continuous culture have been carried out recently, investigating the effects of conditions relevant to heap bioleaching on the microbial ferrous-iron oxidation by Leptospirillum ferriphilum [1-3]. It was postulated that ferric-iron, which is known to be inhibitory, also acts as a stress stimulus, promoting microbial growth at higher total iron concentration. This paper investigates this phenomenon further, by comparing tests run with pure ferrous-iron feeds against those where the feed is partially oxidised to ferric at comparable concentrations. The findings clearly suggest that, contrary to reactor theory, it is indeed ferrous iron concentration in the reactor feed that determines biomass concentration and that ferric iron concentration has little effect on microbial growth. Further mathematical analysis shows that the phenomenon can be explained on the basis of the Pirt equation and the particular reaction conditions employed in the test work.
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Noela Chinyelu Igwemmar, Samuel Esimikwame Kakulu y Mary Sunday Dauda. "Heavy metal concentration in some commercial poultry feeds available in Abuja, Nigeria". World Journal of Advanced Research and Reviews 16, n.º 2 (30 de noviembre de 2022): 005–15. http://dx.doi.org/10.30574/wjarr.2022.16.2.1110.
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The concentrations of heavy metals in some commercial poultry feeds available in Abuja, Nigeria was investigated. Poultry feed rations (starter, grower, finisher and layer) of seven different feed brands available in Abuja were purchased from their various distribution outlets. The nitric acid digestion method followed by Flame Atomic Absorption Spectrophotometry technique were used for metal content quantification. Analytical method validation was performed using IAEA-V-8 Rye flour certified reference material and good recoveries were obtained in all the metals indicating the accuracy of the applied analytical procedure. The mean of heavy metal concentrations (μg/g dry weight) in the poultry feeds were 2.31 ± 1.23, 0.43 ± 0.20, 1.66 ± 0.82, 23.35 ± 5.26, 238.09 ± 45.80, 0.61 ± 0.26, 99.57 ± 15.63 and 68.21 ± 11.92 for Pb, Cd, Ni, Cu, Fe, Co, Mn and Zn respectively. Generally, the levels of iron, manganese, zinc and copper in the poultry feeds were higher than FAO/WHO, National Research Council (NRC) and Standard Organisation of Nigeria (SON) maximum recommended limits in feeds. Pearson correlation analysis on the metals in poultry feeds showed a significant (p < 0.01) positive strong correlations between Co/Ni (0.658), Mn/Cu (r = 0.566), Zn/Cu (r = 0.683) and Zn/Mn (r = 0.758) suggesting that these metals could have had the same pathway into the feeds.
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Widu, A. A., F. U. Datta y M. M. Kleden. "Evaluation of Digestability and Rumen Parameters Through In-vitro Concentrate Containing Binahong Flour as Secondary Compound". Jurnal Sain Peternakan Indonesia 16, n.º 4 (27 de diciembre de 2021): 362–67. http://dx.doi.org/10.31186/jspi.id.16.4.362-367.
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This study was conducted to determine the effect of different levels of binahong flour used in concentrate feed on dry matter digestibility (DMD), organic matter digestibility (OMD), VFA and NH3 concentrations in vitro. The design used was a completely randomized design with 4 treatments and 4 replications. The treatments studied were: R0; concentrate feed without binahong flour, R1; concentrate feed contains 10% binahong flour, R2; concentrate feed containing 20% binahong flour, R3; concentrate feed contains 30% binahong flour. Based on the results of the study, the average DMD (%) R0 73.56±0.75, R1 74.50 ±0.61, R2 74.98±0.70, R3 76.65±0.90, OMD (%) R0 69.50±1.10, R1 69.82±1.00, R2 70.07±0.88, R3 72.61±0.99, VFA concentration (mM) R0 108.53±8.52, R1 110.75±6.51, R2 111.40±2.35, R3 112.77 ±14.76, NH3 concentration (mM) R0 9.74±0.74, R1 10.61±0.44, R2 11.55±0.41, R3 11.55±0.33. The results of statistical analysis confirmed that the treatment had a very significant effect on the increase in DMD, OMD, NH3 (P<0,01), but not significant on the total VFA concentration. The conclusion of this study is that the use of binahong flour up to a level of 30% in concentrate feed has an effect on increasing in DMD, OMD, VFA, and NH3 concentrations in vitro.
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Van Limbergen, Tommy, Mathias Devreese, Siska Croubels, Nathan Broekaert, Annelies Michiels, Sarah De Saeger y Dominiek Maes. "Role of mycotoxins in herds with and without problems with tail necrosis in neonatal pigs". Veterinary Record 181, n.º 20 (5 de octubre de 2017): 539. http://dx.doi.org/10.1136/vr.104385.
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This study aimed to investigate a possible involvement of mycotoxins in neonatal tail necrosis in piglets. Ten affected and 10 non-affected farms were selected. Sow feed samples were analysed for the presence of 23 mycotoxins by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Blood plasma samples of sows and their piglets were analysed for the presence of deoxynivalenol (DON), de-epoxydeoxynivalenol, T-2 and HT-2 toxin, zearalenone, alfa-zearalenol, and beta-zearalenol, using LC-MS/MS. Additionally, high-resolution mass spectrometry (HRMS) was performed to detect DON-glucuronide (DON-Glca). There was a significant difference between case herds and control herds for mean DON concentrations in feed and sow plasma. For piglet samples, concentrations of DON were above the limit of quantification of 0.1 ng/ml in only 12 samples. Positive correlations were found between DON concentrations in sow feed and plasma of sows; DON concentration in sow feed and DON-Glca concentration in plasma of sows; and between DON and DON-Glca concentration in sow-plasma. In conclusion, high prevalence of DON in feed samples was found, with significantly higher concentrations in case herds, as well as the presence of DON and DON-Glca in sow plasma. Additional research is needed to identify risk factors, including within-herd factors, associated with neonatal tail necrosis in piglets.
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Silva, Gleise M., Federico Podversich, Ana C. G. Luna, Gonzalo Barreneche y Nicolas DiLorenzo. "PSXI-26 Assessing diet integrity and potential sorting behavior in backgrounding diets fed in a GrowSafe feed intake monitoring system". Journal of Animal Science 97, Supplement_3 (diciembre de 2019): 400. http://dx.doi.org/10.1093/jas/skz258.797.
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Abstract The integrity of a diet fed as a total mixed ration (TMR) in feedlot and backgrounding scenarios is essential to maintain animal performance and minimized digestive upsets. The objective of this study was to quantify crude protein (CP), dry matter (DM) and ash concentration of a backgrounding diet fed as a TMR in a GrowSafe feed intake monitoring system. Angus crossbreed heifers (n = 70; 360 ± 60 kg of BW; 470 ± 26 d of age) and steers (n = 20; 386 ± 65 kg of BW; 465 ± 30 d of age) were allocated to 18 concrete-floored pens (108 m2), equipped with two GrowSafe feed bunks each to receive a backgrounding diet fed ad libitum as a TMR. Diet was comprised of (DM basis): 35% cottonseed hulls, 34% cracked corn grain, 20% pelleted corn gluten feed, 5% cottonseed meal, 4% liquid supplement (molasses-based), and 2% limestone. Feed samples were collected from three segments of each bunk (top; TOP, middle; MID, and bottom; BOT).Samples from the TOP was collected immediately after feed was provided and further samplings were conducted when feed was consumed throughout the day to obtain the MID and BOT samples in a 24 h interval. Approximately 90 kg (as fed) of the TMR was provided at 0800 h in each clean feed bunk. Concentration of CP did not differ (P = 0.89) throughout the day. However, DM content decreased as feed was consumed (P < 0.001). Concentration of ash was greater for the MID and BOT portions compared to TOP (P = 0.04). In conclusion, CP concentrations in the backgrounding diet fed were not altered throughout the day as diet was consumed. Increased ash concentration towards the bottom of the feed bunk prior to the new feed delivery may result from vertical stratification of the TMR.
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Putri, Alamanda Juwita, Salnida Yuniarti Lumbessy y Dewi Putri Lestari. "Substitusi Tepung Rumput Laut Eucheuma striatum pada Pakan Ikan Nila (Oreochromis niloticus)". Bioscientist : Jurnal Ilmiah Biologi 9, n.º 2 (30 de diciembre de 2021): 333. http://dx.doi.org/10.33394/bioscientist.v9i2.3972.
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Feed is one of the most influential factors on the appearance of tilapia productivity. This study aimed to analyze the effect of substitution of fish feed with Eucheuma striatum seaweed meal on the cultivation of Tilapia (Oreochromis. niloticus). This research was conducted at the Laboratory of Aquaculture Study Program, Faculty of Agriculture, Mataram University. The method used in this study was a completely randomized design (CRD), which consisted of 4 treatments with 3 replications, ie: control (P1), concentration of 4% seaweed flour (P2), concentration of 8% seaweed flour (P3), and concentration of 12% seaweed flour (P4). The results showed that substitution of fish feed with seaweed meal E. striatum could affect growth and specific growth rate, but did not affect Feed Utilization Efficiency (EPP), Feed Conversion Ratio (FCR), and Survival Rate (SR) of Tilapia. Fortification of E. striatum flour at concentrations of 4% and 8% in feed gave better absolute and specific weight growth of Tilapia, while the best absolute length growth was found in the addition of 8% E. striatum flour, which was 2.26 cm.
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IQBAL, SHAHZAD ZAFAR, MUHAMMAD RAFIQUE ASI, SONIA NISAR, KHALID MAHMOOD ZIA, SELAMAT JINAP y NOEEN MALIK. "A Limited Survey of Aflatoxins and Zearalenone in Feed and Feed Ingredients from Pakistan". Journal of Food Protection 79, n.º 10 (1 de octubre de 2016): 1798–801. http://dx.doi.org/10.4315/0362-028x.jfp-16-091.
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ABSTRACT This work presents current information on the presence of aflatoxins (AFs) and zearalenone (ZEN) in feed and feed ingredients from Punjab, Pakistan. The 105 samples tested were concentrated feed, i.e., cotton seed meal (18 samples) and soybean meal (14), and feed ingredients, i.e., crushed corn (17), crushed wheat (15), barley (17). and poultry feed (24). Samples were analyzed using high-performance liquid chromatography equipped with a fluorescence detector. Analysis revealed that 69 of 105 samples were contaminated with AFs, and the highest mean concentrations of AFB1 (6.20 μg/kg) and total AFs (9.30 μg/kg) were found in poultry feed samples. The mean total AF concentrations ranged from the limit of quantification to 165.5 μg/kg. However, 75 of the 105 samples were positive for ZEN. The highest mean concentration (19.45 μg/kg) was found in poultry feed samples. The mean ZEN concentrations were 0.15 to 145.30 μg/kg. The prevalence of AFs and ZEN was high in feed and feed ingredients and needs urgent attention.
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Doherty, Stephen J., Allen Fox y David W. Fink. "Determination of Ivermectin in Medicated Swine Feeds at the 2 ppm Concentration Level". Journal of AOAC INTERNATIONAL 73, n.º 6 (1 de noviembre de 1990): 931–34. http://dx.doi.org/10.1093/jaoac/73.6.931.
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Abstract An analytical method has been developed that Is applicable to the determination of Ivermectin in medicated feeds at the 2 ppm concentration level. It Is based upon liquid chromatographic analysis with a reverse-phase column and ultraviolet detection. After the drug Is extracted from the feed Into methanol, an analytical sample Is prepared by the consecutive use of column chromatography on alumina and solidphase extraction on Sep-Pak C18 and silica cartridges. This procedure has been applied to the concentration range 0.50- 3.0 ppm of Ivermectin In feed with an accuracy of ±2% mean relative error and a precision of ± 2% relative standard deviation at the 2 ppm concentration level.
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Simonetti, Serena, Agus Saptoro, Claudia Fernández Martín y Davide Dionisi. "Product Concentration, Yield and Productivity in Anaerobic Digestion to Produce Short Chain Organic Acids: A Critical Analysis of Literature Data". Processes 8, n.º 12 (25 de noviembre de 2020): 1538. http://dx.doi.org/10.3390/pr8121538.
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In order to make anaerobic digestion-based processes for short chain organic acid (SCOA) production attractive, the key performance variables, i.e., concentration, yield, and productivity of the produced SCOAs need to be maximised. This study analysed recent literature, looking for the effect of process operating parameters (feed concentration, pH, temperature, and residence time) on the performance variables. Data from 551 experiments were analysed. Mean values of the SCOA concentration, yield, and productivity were 10 g l−1, 32% (chemical oxygen demand (COD) COD−1), and 1.9 g l−1 day−1, respectively. Feed concentration and residence time had the most important effect. Higher feed concentration corresponded to higher product concentration and productivity, but to lower yield. The mean feed concentration was 109 gCOD l−1 and 19 gCOD l−1 in the experiments with the highest product concentrations and in the experiments with the highest yields, respectively. Shorter residence times corresponded to higher productivity. The mean HRT (hydraulic residence time) in the experiments with the highest productivities was 2.5 days. Sequencing batch reactors gave higher values of the performance variables (mean values 29 g l−1, 41% COD COD−1, and 12 g l−1 day−1 for product concentration, yield, and productivity, respectively) than processes without phase separation.
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Yuan, Zhi Tao, Lei Liu y Yue Xin Han. "Wet Pre-Concentration of Low-Grade Hematite in High-Pressure Grinding Roller". Advanced Materials Research 454 (enero de 2012): 363–68. http://dx.doi.org/10.4028/www.scientific.net/amr.454.363.
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The wet pre-concentration of comminuted hematite in high-pressure grinding roller was studied, using the cylindrical ferromagnetic medium in a high gradient magnetic separator. The effects of various factors including rod diameter, rod gap and background magnetic field intensity (BMFI) on the performances of pre-concentration in different size feeds are emphatically investigated. The results showed that as the rod diameter increased, the rod gap decreased and the BMFI increased, the tailings grade and the tailings yield reduced, but the concentrates recovery raised. This variation was regardless of the feed size distribution. After the classifying pre-concentration, the overall concentrate grade increases by 9.56 percentage points and the concentrate recovery is up to the 82.67% with a tailing grade of 10.68% and a tailing yield of 40.31%. Compared with the classifying pre-concentration, the full size pre-concentration produced a concentrate with a lower grade only increased by 6.61 percentage points and the higher recovery of 92.32%. The tailings, with a lower yield of only 26.62% and a lower grade of 7.39%, was mainly produced from the fine feed. The coarse feed in the full size pre-concentration was not separated effectively.
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Mgbeahuruike, Anthony Christian, Toochukwu Eleazar Ejiofor, Michael Ushie Ashang, Chiamaka Ojiako, Christian C. Obasi, Chuka Ezema, Obianuju Okoroafor, Mulunda Mwanza, Magnus Karlsson y Kennedy F. Chah. "Reduction of the Adverse Impacts of Fungal Mycotoxin on Proximate Composition of Feed and Growth Performance in Broilers by Combined Adsorbents". Toxins 13, n.º 6 (21 de junio de 2021): 430. http://dx.doi.org/10.3390/toxins13060430.
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Synergistic interaction of adsorbents in reducing the adverse impacts of mycotoxin on performance and proximate composition of broiler feeds was investigated. Fungal growth was induced by sprinkling water on the feed. S. cerevisiae + bentonite, kaolin + bentonite or S. cerevisiea + kaolin adsorbent combinations (1.5 g/kg feed) were added and the feeds were stored in black polythene bags. An untreated group was kept as a positive control while fresh uncontaminated feed was used as a negative control. Mycotoxins were extracted from the feeds and quantified using reverse phase HPLC. Proximate composition, nutrient digestibility of the feeds, feed intake and weight gain of the broilers were measured. Deoxynivalenol (DON) concentration in the contaminated/untreated feed was 347 µg/kg while aflatoxin B1 (AFB1) was 34 µg/kg. Addition of bentonite and kaolin in the contaminated feed reduced AFB1 and DON to significantly lower levels. Feed intake and weight gain were low in the broilers fed the contaminated feed. The carbohydrate level was significantly (p < 0.05) reduced from 62.31 to 40.10%, crude protein digestibility dropped from 80.67 to 49.03% in the fresh feed and contaminated feed respectively. Addition of the adsorbents (S. cerevisiae and bentonite) significantly (p < 0.05) improved these parameters.
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Ma, Jianyu, Mehdi Mahmoodinia, Kumar R. Rout y Edd A. Blekkan. "The Impact of Operating Parameters on the Gas-Phase Sulfur Concentration after High Temperature Sulfur Sorption on a Supported Mo-Mn Sorbent". Reactions 2, n.º 4 (23 de septiembre de 2021): 365–73. http://dx.doi.org/10.3390/reactions2040023.
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The impact of operating parameters on H2S capture from a syngas mixture by a Mo-promoted Mn-based high-temperature sorbent was investigated. The parameters investigated included temperature, space velocity, H2S concentration in the feed gas, and steam content. The H2S and SO2 concentrations in the gas after passing over a bed of the sorbent were analyzed and compared with thermodynamic calculations. The results confirmed that low temperature, low space velocity, low H2S concentration, and a dry feed were favorable for achieving a low residual concentration of sulfur compounds in the effluent gas. The sorbent was able to reduce the residual H2S concentration to below 1 ppm under all tested conditions. However, the unavoidable steam content in the gas phase had a significant adverse effect on sulfur removal from the gas. An empirical model, containing the three variables, i.e., temperature, space velocity, and H2S concentration in the feed, was developed and can be used to predict the effluent H2S residual concentration after treatment by the 15Mn8Mo sorbent.
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Ghasem, Nayef M. y Hasan Orbey. "Effect of Feed Concentration in Equilibrium Parametric Pumps". Separation Science and Technology 22, n.º 12 (diciembre de 1987): 2339–51. http://dx.doi.org/10.1080/01496398708057190.
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Bouma, Andrew T. y John H. Lienhard. "Split-feed counterflow reverse osmosis for brine concentration". Desalination 445 (noviembre de 2018): 280–91. http://dx.doi.org/10.1016/j.desal.2018.07.011.
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Pokharel Bhattarai, Bindu, Bhabindra Niroula y Sasinath Jha. "Use of the Greater Duckweed as feed for the Tilapia fish". Nepalese Journal of Biosciences 7, n.º 1 (1 de junio de 2017): 117–19. http://dx.doi.org/10.3126/njbs.v7i1.41799.
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The fresh weight gain of the Nile tilapia individuals reared on different feeds for 21 days occurred in the order: conventional feed (65%) > conventional feed and duckweed powder in equal proportion (37%) > duckweed powder (09%). The conventional feed and duckweed powder were insignificantly different from each other in protein and phosphorus, but significantly different (P<0.05) in fat, total ash and calcium contents. The tilapia individuals reared on the mixture of the conventional feed and duckweed powder had significantly (P<0.05) highest concentration of proteins (50.3%) than those reared on either conventional feed (45.34%) or duckweed powder (45.79%) alone.
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Oyekola, Oluwaseun O., Robert P. van Hille y Susan T. L. Harrison. "Effect of Sulphate Concentration on the Community Structure and Activity of Sulphate Reducing Bacteria". Advanced Materials Research 20-21 (julio de 2007): 513–15. http://dx.doi.org/10.4028/www.scientific.net/amr.20-21.513.
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This study investigated the effect of sulphate concentration and residence time on the performance of anaerobic sulphate reduction by a mixed sulphate reducing bacteria (SRB) culture using lactate as the sole carbon source and electron donor. The process performance is related to the population structure of the microbial consortia and dominant metabolic reactions. Laboratory scale chemostat cultures at different residence times (1-4 d) and sulphate concentrations (1.0-10.0 g/L) were employed. Lactate oxidation was prevalent at feed sulphate concentrations of 1.0 to 5.0 g/L. A corresponding increase in the volumetric sulphate reduction rate with increasing volumetric loading rate was also observed at this range. However, at the higher feed sulphate concentration range (10.0-15.0 g/L), sulphate inhibition, lactate fermentation and an increased microbial diversity were evident. At each feed concentration of sulphate in the range 5.0 to 15.0 g/L, varying dilution rates resulted in significant shifts in dominant metabolic reactions. Sulphate concentration and residence time have significant effects on both the structure of the microbial population and kinetics of biological sulphate reduction.
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Rizwan-U- Zama, Ayesha Siddiqa, A. N. Thobbi, Tehseen Sajid Mudhol y R Shruthi. "The Consequences of Prior Initiation of Breast Feeding on Blood Glucose Levels in Neonates Born In a Tertiary Care Hospital". Asian Journal of Clinical Pediatrics and Neonatology 8, n.º 2 (9 de julio de 2020): 23–29. http://dx.doi.org/10.47009/ajcpn.2020.8.2.5.
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Background: Hypoglycemia is the most common event of failure of metabolic adjustments in the newborn. Changes in maternal and fetal monitoring techniques, administration of glucose-containing solutions during labor, delivery and early feeding in neonates significantly alter blood glucose concentrations during the first week of postnatal life. Subjects and Methods: A total of 90 healthy (60 born by FTND, 30 born by LSCS) term, AGA infants were longitudinally evaluated at birth, at one hour after feeds (post feed), and after 6 hours of life. Plasma glucose was estimated from Heel Prick capillary samples by glucometer method. The influence of mode of delivery, the interval between feeds, sex, birth weight, on blood glucose was analyzed. Results: The way of delivery did not affect the plasma glucose concentration in neonates. There was a substantial increase in blood glucose concentration after the first feed irrespective of their birth weight. It was found that female babies had a higher blood glucose concentration than male babies during our study period. All babies maintained normal blood glucose with the continuation of breastfeeding. Conclusion: Plasma glucose levels are satisfactorily maintained in healthy term infants without resort to pre-lacteal feeds and mode of delivery did not influence plasma glucose. There is no need to check blood glucose levels routinely in an asymptomatic, healthy, term, breastfed infants.
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Petit, H. V. "Review: Feed intake, milk production and milk composition of dairy cows fed flaxseed". Canadian Journal of Animal Science 90, n.º 2 (1 de junio de 2010): 115–27. http://dx.doi.org/10.4141/cjas09040.
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Flaxseed contains approximately 55% of total fatty acids of the oil as ?-linolenic acid and is rich in lignans, which are strong antioxidants. Diets rich in omega-3 fatty acids and antioxidants are known to have beneficial effects on human health such as a decrease in the incidence of cancer, cardiovascular diseases, hypertension, and arthritis. Flaxseed could then be an interesting natural feed to consider for changing milk composition. Cyanogenic glycosides (linustatin and neolinustatin) are present in flaxseed, but the concentration of hydrocyanic acid is very low in milk and ruminal fluid of cows fed flaxseed products. In general, feeding up to 15% of the total dry matter as whole flaxseed has a limited effect on dry matter intake. Heat treatments such as micronization and extrusion have no effect on dry matter intake and the effect of formaldehyde treatment on feed intake is unclear. The effects of flaxseed supplementation on milk production of dairy cows in the early stage of lactation have been neutral. Diet supplementation with whole flaxseed has had no effect on milk yield and composition of dairy cows in the mid or late stages of lactation. Physical processing of flaxseed increased milk production although heat treatment did not. Results on the effect of flaxseed processing on overall milk fat concentration have been controversial, but heat and formaldehyde treatments had no effect. Flaxseed supplementation had no effect on milk fat and protein concentrations, and processing of flaxseed had little effect. The extent of change in the concentration of fatty acids in milk is generally proportional to the level of inclusion of flaxseed in the diet. In conclusion, feeding flaxseed does not affect milk production or composition in the large majority of studies, but its long-term effects on health of cows and productivity still need to be determined.Key words: Review, flax, dairy
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Diener, S., C. Zurbrügg y K. Tockner. "Bioaccumulation of heavy metals in the black soldier fly, Hermetia illucens and effects on its life cycle". Journal of Insects as Food and Feed 1, n.º 4 (7 de diciembre de 2015): 261–70. http://dx.doi.org/10.3920/jiff2015.0030.
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In developing countries, effective waste management strategies are constrained by high collection costs and lack of adequate treatment and disposal options. The organic fraction in particular, which accounts for more than 50% of the waste production, constitutes a great, yet mostly neglected, reuse potential. Concomitantly, the demand for alternative protein sources by the livestock feed industry is sharply increasing. A technology that effectively transforms organic waste into valuable feed is therefore a timely option. Larvae of the non-pest black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae), may be used to reduce the mass of organic waste significantly. Concurrently, larval feeding converts organic waste into prepupae (last larval stage) which is high in protein. In combination with a viable market, this potential animal feed may cover the waste collection costs and thus promote innovative, small-scale entrepreneurs to establish a profitable business niche. Organic waste, however, often contains persistent pollutants, such as heavy metals, that may accumulate in the larvae and prepupae of black soldier flies and consequently in the food chain. In this study, we fed black soldier fly larvae chicken feed spiked with heavy metals (cadmium, lead and zinc at three concentrations each) to examine the extent of metal accumulation in the different life stages and the effect of heavy metal concentration in the feed on the life cycle determinants of the flies. The cadmium accumulation factor in prepupae (metal concentration in the body divided by metal concentration in the food) ranged between 2.32 and 2.94; however, the lead concentration remained well below its initial concentration in the feed. The bioaccumulation factor of zinc in prepupae decreased with increasing zinc concentration in the feed (from 0.97 to 0.39). None of the three heavy metal elements had significant effects on the life cycle determinants (prepupal weight, development time, sex ratio).
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Soison, Pichai, Pakpoom Supachart y Pratarn Wongsarivej. "Effect of Feed-Flow Rate in a Solid-Liquid Hydrocyclone Based on Total Solid Recovery Equation". Key Engineering Materials 751 (agosto de 2017): 173–79. http://dx.doi.org/10.4028/www.scientific.net/kem.751.173.
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Many studies of hydrocyclones have confirmed that increasing the feed-flow rate results in a higher separation efficiency. The purpose of this study was to investigate the separation efficiency for a 100 mm solid–liquid hydrocyclone with 1 and 2 wt% solid concentrations at feed-flow rates of 2, 3, 4, 5 and 6 m3/hr. The solid concentration and particle size distribution were analysed using drying–weighing and a particle-size analyser (Mastersizer 2000), respectively. The experimental results indicated that an increase in feed-flow rate from 2 to 4 m3/hr produced decreased separation efficiency. However, when the feed-flow rates increased from 4 to 6 m3/hr, the separation efficiency increased. Furthermore, the higher the feed-flow rate, the smaller the cut size. A novel separation efficiency equation in terms of the concentration ratio and flow ratio is also proposed.
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GONG, P. S., S. L. JENG, Y. F. HSU, C. C. LIN y S. Y. LIN. "Development of a Method for the Determination of Pyrimethamine Concentrations in Feeds by Ion-Pairing High-Performance Liquid Chromatography". Journal of Food Protection 65, n.º 4 (1 de abril de 2002): 688–91. http://dx.doi.org/10.4315/0362-028x-65.4.688.
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An ion-pairing reversed-phase high-performance liquid chromatography (HPLC) method with diode array detection at 280 nm was developed to determine pyrimethamine concentrations in feed for laying hens. Pyrimethamine was extracted with a mixture of 5% isobutanol and 95% benzene, and the extract was cleaned up on an alumina column. The drug was eluted from an Intersil ODS-3V column (250 by 4.6 mm) with a mixture of 25% acetonitrile and 75% water (vol/vol) containing 0.01 M tetramethylammonium chloride as an ion-pairing agent and adjusted with acetic acid to pH 3.5. The flow rate was 1.0 ml/min. Mean recovery of pyrimethamine from supplemented feeds at concentrations of 2, 4, and 5 μg/g of feed were 100.5, 103.5, and 100.8%, respectively. Precision within a day ranged from 4.3 to 7.0% for the three concentrations, and day-to-day precision was 5.3% for feed supplemented at a concentration of 4 μg/g. No chromatographic interference was detected from other 2,4-diaminopyrimidine compounds or other major drugs used in poultry.
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Liu, Dawei, Chao Gu, Changhu Lu, Qinghua Wu, Kamil Kuca y Wenda Wu. "Red-Crowned Crane (Grus japonensis) Reproduction Was Improved by Inhibiting Mycotoxins with Montmorillonite in Feed". Toxins 12, n.º 3 (18 de marzo de 2020): 191. http://dx.doi.org/10.3390/toxins12030191.
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The red-crowned crane (Grus japonensis) is a vulnerable bird species. Mycotoxins are toxic substances produced by filamentous fungi and are considered as naturally unavoidable contaminants in animal feed. Our recent survey indicated that feeds designed for captive red-crowned cranes were contaminated with mycotoxins. This study was conducted to investigate the protective effects of the mycotoxin binder montmorillonite on the reproductive behavior, sex hormone levels, and egg quality of red-crowned cranes. Twelve pairs of G. japonensis were divided into four groups, and each group was fed one of the following: a selected diet (with extra low levels of mycotoxins), a regular diet, a selected diet with 0.5% montmorillonite added, or a regular diet with 0.5% montmorillonite added. Consumption of the regular diet decreased courtship and mating behaviors, testosterone concentration, egg weight, and shell thickness. However, feed supplementation with montmorillonite increased the courtship, mating behaviors and testosterone concentration during the pre-breeding period, as well as egg weight and shell thickness. These findings suggest that the addition of dietary montmorillonite is effective for controlling mycotoxins in the feed, resulting in improvements in reproductive behaviors, testosterone concentrations, and some egg quality parameters of the red-crowned crane.
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Li, Yan Feng, Wen Feng Huang, Rong Tao Zhu y Wen Da Zhao. "Influence of Processing Parameters on Dehydration Effect of Positive-Pressure Horizontal Filtration". Advanced Materials Research 524-527 (mayo de 2012): 997–1006. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.997.
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The structure of filter cake obtained by the positive horizon pressure filtration process has more advances. The paper investigated some main influencing factors about feed concentration, filtration pressure, feed grain composition on dehydration effect. And paper designs the testing program and analyses the testing results. Then paper establish the mathematical model about the filter cake moisture, filtrate concentration, the capacity of handling dry slime and the experiment influence variables. The results show that the filter mass moisture decreases as the increase of feed concentration, filtration pressure and feed size. At the same time, the filtration time, filtration pressure and feed concentration have a little influence on filtration concentration, and handling capacity of dry slime has a proportion with feed concentration and filtration pressure and has a inversely-proportional relationship with filtration time.
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Marini, Danila, Joe Pippia, Ian G. Colditz, Geoff N. Hinch, Carol J. Petherick y Caroline Lee. "Palatability and pharmacokinetics of flunixin when administered to sheep through feed". PeerJ 4 (14 de marzo de 2016): e1800. http://dx.doi.org/10.7717/peerj.1800.
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Applying analgesics to feed is a potentially easy method of providing pain-relief to sheep and lambs that undergo painful husbandry procedures. To be effective, the medicated feed needs to be readily accepted by sheep and its consumption needs to result in therapeutic concentrations of the drug. In the present experiment, pelleted feed was supplemented with flunixin (4.0 mg/kg live weight) and offered to eight sheep. To test the palatability of flunixin, the individually penned sheep were offered normal feed and feed supplemented with flunixin in separate troughs for two consecutive days. A trend for a day by feed-type (control versus flunixin supplemented) interaction suggested that sheep may have had an initial mild aversion to pellets supplemented with flunixin on the first day of exposure, however, by on the second day there was no difference in consumption of normal feed and feed supplemented with flunixin. To test pharmacokinetics, sheep were offered 800 g of flunixin supplemented feed for a 12 h period. Blood samples were taken over 48 h and plasma drug concentrations were determined using ultra-high-pressure liquid chromatography, negative electrospray ionisation and tandem mass spectrometry. The mean ± S.D. time required to reach maximum concentration was 6.00 ± 4.14 h and ranged from 1 to 12 h. Average maximum plasma concentration was 1.78 ± 0.48 µg/mL and ranged from 1.61 to 2.80 µg/mL. The average half-life of flunixin was 7.95 ± 0.77 h and there was a mean residence time of 13.62 ± 1.17 h. Free access to flunixin supplemented feed enabled all sheep to obtain inferred therapeutic concentrations of flunixin in plasma within 6 h of starting to consume the feed. Provision of an analgesic in feed may be an alternative practical method for providing pain relief to sheep.